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Cited by 17Neuroinflammation and Neurodegeneration MechanismsSex and Gender in HealthcareGenetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities

Sex chromosomes and sex hormones differently shape microglial properties during normal physiological conditions in the adult mouse hippocampus

Open access
Bobotis, Bianca Caroline, Khakpour, Mohammadparsa, Braniff, Olivia, de Andrade, Elisa Gonçalves, Gargus, Makenna, Allen, Micah, Carrier, Micaël, Baillargeon, Joanie +2 more·2025·Journal of Neuroinflammation
DOI 10.1186/s12974-025-03341-6PMC PMC11762133
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Abstract

The brain presents various structural and functional sex differences, for which multiple factors are attributed: genetic, epigenetic, metabolic, and hormonal. While biological sex is determined by both sex chromosomes and sex hormones, little is known about how these two factors interact to establish this dimorphism. Sex differences in the brain also affect its resident immune cells, microglia, which actively survey the brain parenchyma and interact with sex hormones throughout life. However, microglial differences in density and distribution, morphology and ultrastructural patterns in physiological conditions during adulthood are largely unknown. Here, we investigated these aforementioned properties of microglia using the Four Core Genotypes (FCG) model, which allows for an independent assessment of gonadal hormones and sex chromosomal effects in four conditions: FCG XX and Tg XY− (both ovaries); Tg XXSry and Tg XYSry (both testes). We also compared the FCG results with XX and XY wild-type (WT) mice. In adult mice, we focused our investigation on the ventral hippocampus across different layers: CA1 stratum radiatum (Rad) and CA1 stratum lacunosum-moleculare (LMol), as well as the dentate gyrus polymorphic layer (PoDG). Double immunostaining for Iba1 and TMEM119 revealed that microglial density is influenced by both sex chromosomes and sex hormones. We show in the Rad and LMol that microglia are denser in FCG XX compared to Tg XYSry mice, however, microglia were densest in WT XX mice. In the PoDG, ovarian animals had increased microglial density compared to testes animals. Additionally, microglial morphology was modulated by a complex interaction between hormones and chromosomes, affecting both their cellular soma and arborization across the hippocampal layers. Moreover, ultrastructural analysis showed that microglia in WT animals make overall more contacts with pre- and post-synaptic elements than in FCG animals. Lastly, microglial markers of cellular stress, including mitochondrion elongation, and dilation of the endoplasmic reticulum and Golgi apparatus, were mostly chromosomally driven. Overall, we characterized different aspects of microglial properties during normal physiological conditions that were found to be shaped by sex chromosomes and sex hormones, shading more light onto how sex differences affect the brain immunity at steady-state.

AI snapshot

Written from the paper’s full text.

TL;DR

Using the Four Core Genotypes model in adult mice, this study shows that microglial density, distribution, and morphology in the ventral hippocampus are shaped by interacting sex chromosome and gonadal hormone effects, while ultrastructural stress markers are mostly chromosomally driven. WT and FCG mice also differ, and peripheral myeloid infiltration is increased in the CA1 LMol of ovary-bearing FCG XX mice.

Key findings

  • Microglial density was influenced by both sex chromosomes and hormones. In CA1 Rad, Tg XYSry microglia were denser than FCG XX (163.7 ± 6.3 vs 95.8 ± 4.5 cells/mm², p = 0.0145), while WT XX were densest (190.7 ± 12.3 vs FCG XX, p = 0.0004). In CA1 LMol, WT XX were denser than FCG XX (259.6 ± 16.8 vs 141.6 ± 7.2, p < 0.0001) and WT XY (173.9 ± 6.8, p = 0.0024). In PoDG, ovary-bearing animals had higher density: FCG XX vs Tg XXSry (358.7 ± 21.9 vs 205.9 ± 18.6, p = 0.0059), FCG XX vs Tg XYSry (175.6 ± 9.1, p = 0.0008), and WT XX vs WT XY (455.5 ± 23.5 vs 122.4 ± 6.9, p < 0.0001).
  • Microglial morphology showed complex hormone × chromosome interactions. In Rad, Tg XY− had larger soma area than Tg XYSry (52.8 ± 1.4 vs 44.0 ± 1.3 µm², p = 0.0002), and FCG XX had smaller arborization area than Tg XYSry (1979.9 ± 94.7 vs 2796.8 ± 92.9 µm², p = 0.0475). In LMol, WT XX had the smallest soma area vs FCG XX (36.1 ± 0.9 vs 44.0 ± 1.8, p = 0.0213). In PoDG, FCG XX showed decreased arborization solidity vs Tg XXSry (0.7 ± 0.0 vs 0.8 ± 0.0, p = 0.0320).
  • Ultrastructurally, WT mice made more synaptic contacts than FCG mice. WT XY had nearly double the pre-synaptic contacts of Tg XYSry (5.2 ± 0.4 vs 3.0 ± 0.3, p = 0.0008), and WT XY made more post-synaptic contacts than WT XX (1.8 ± 0.2 vs 0.95 ± 0.1, p = 0.0196). Stress markers were mostly chromosomally driven: ER/Golgi dilation was higher in FCG XX than WT XX (0.8 ± 0.2 vs 0.1 ± 0.0, p = 0.0166), and extracellular digestion was higher in Tg XYSry than FCG XX and Tg XXSry (0.9 ± 0.1 vs 0.3 ± 0.0, p = 0.0039; vs 0.3 ± 0.1, p = 0.0153). Nuclear/cytoplasmic membrane circularity and solidity were sex-chromosomally affected; Tg XYSry vs WT XY showed reduced nuclear circularity (0.7 ± 0.0 vs 0.8 ± 0.0, p = 0.0222), cytoplasmic circularity (0.5 ± 0.0 vs 0.6 ± 0.0, p = 0.0018), and cytoplasmic solidity (0.8 ± 0.0 vs 0.9 ± 0.0, p = 0.0160).
  • Peripheral myeloid infiltration was increased in CA1 LMol of ovary animals. FCG XX had more Iba1+/TMEM119− cells than WT XX, Tg XXSry, and Tg XYSry (2.8 ± 0.6% vs 0.4 ± 0.1, 0.3 ± 0.1, and 0.4 ± 0.1; p = 0.0270, 0.0218, and 0.0241, respectively); Rad and PoDG showed no significant infiltration differences.

Methods

  • Adult Four Core Genotypes (FCG) and wild-type mice at postnatal day 110 were used, focusing on ventral hippocampus CA1 stratum radiatum (Rad), CA1 stratum lacunosum-moleculare (LMol), and dentate gyrus polymorphic layer (PoDG). Immunofluorescence used N = 5 mice/group; scanning electron microscopy used N = 4 mice/group; morphology analyzed n = 15 cells/animal/condition (1,350 cells total); ultrastructure analyzed 271 microglia at n = 10–12 cells/animal/group.
  • Microglia were identified by double immunostaining for Iba1 and TMEM119 with DAPI, imaged by epifluorescence and confocal microscopy for density/distribution and morphology, and by immunoperoxidase Iba1 staining followed by scanning electron microscopy for ultrastructure. Analyses used Fiji and QuPath with manual tracing/counting.
  • Statistical comparisons used ordinary two-way ANOVA for sex hormones (ovaries vs testes) and genotype (FCG XX vs FCG XY vs WT), followed by Tukey post-hoc tests where significant; significance was set at p < 0.05. The paper notes some datasets were not normally distributed but ordinary two-way ANOVA was still used because no non-parametric version was available.

Limitations

  • Stated: the FCG model has altered gonadal phenotypes—Tg XXSry mice have smaller testes and lack sperm, while Tg XY− mice lose germ cells, have smaller ovaries, and stop estrous cycling earlier, making both less fertile. A recent report of a 3.2 MB X-Y translocation in the Jackson strain 010905 causing upregulation of X-linked genes (including Tlr7) in Tg XY− and Tg XYSry genotypes may have influenced results. FCG XX vs WT XX differences may also reflect an epigenetic signature from the Tg XY− sire or estrous-cycle/hormonal fluctuations.
  • Stated: density and morphometric analyses provide estimates rather than precise stereological counts; unbiased stereology is recommended for future studies. Molecular mechanisms and comparisons with other cell types were not examined, and some datasets were non-normal yet analyzed with two-way ANOVA.
  • Evident from the text: ultrastructural analysis was restricted to CA1 Rad, so ultrastructural conclusions do not cover LMol or PoDG; estrous-cycle staging is not reported, and sample sizes are modest (N = 4–5 mice/group).

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1186/s12974-025-03341-6

Cites

136 of 136 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

53 of 97 cited sources checked · 17 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    Gene expression of microglia differs between males and females.

    “Additionally, gene expression of microglia differs between males and females [44, 45].”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [44] Guneykaya D, Ivanov A, Hernandez DP, Haage V, Wojtas B, Meyer N, et al. Transcriptional and Translational Differences of Microglia from male and female brains. Cell Rep. 2018;24:2773–e27836. source
    • cites [45] Villa A, Gelosa P, Castiglioni L, Cimino M, Rizzi N, Pepe G, et al. Sex-specific features of Microglia from Adult mice. Cell Rep. 2018;23:3501–11. source
  • Premisecitation

    The FCG mouse model allows for an independent assessment of gonadal hormones and sex chromosomal effects.

    “we used the Four Core Genotypes (FCG) mouse model, which allows for an independent assessment of gonadal hormones and sex chromosomal effects [47–49].”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [47] Itoh Y, Mackie R, Kampf K, Domadia S, Brown JD, O’Neill R, et al. Four core genotypes mouse model: localization of the sry transgene and bioassay for testicular hormone levels. BMC Res Notes. 2015;8:69. source
    • cites [48] Lovell-Badge R, Robertson E. XY female mice resulting from a heritable mutation in the primary testis determining gene, Tdy. Development. 1990;109:635–46. source
    • cites [49] De Vries GJ, Rissman EF, Simerly RB, Yang L-Y, Scordalakes EM, Auger CJ, et al. A model system for study of sex chromosome effects on sexually dimorphic neural and behavioral traits. J Neurosci. 2002;22:9005–14. source
  • Premisecitation

    Microglia are highly affected by sex hormones.

    “Microglia, which are the resident innate immune cells of the CNS, are highly affected by sex hormones [14, 16–20].”
    Quote in the paperSubstantial claim6 of 6 sources checked
    • cites [14] Hui CW, Vecchiarelli HA, Gervais É, Luo X, Michaud F, Scheefhals L, et al. Sex differences of Microglia and synapses in the hippocampal dentate gyrus of adult mouse offspring exposed to maternal Immune activation. Front Cell Neurosci. 2020;14:558181. source

      The Introduction (page unavailable) describes substantial sex differences in microglial development, morphology, and activity, and the Discussion reports sex-specific microglial changes in the mouse model. The paper does not establish that sex hormones cause those differences or show that microglia are highly affected by them. (LLM, conf=0.79)

      Experimental — accuracy not yet measured
    • cites [16] Bordeleau M, Lacabanne C, Fernández de Cossío L, Vernoux N, Savage JC, González-Ibáñez F, et al. Microglial and peripheral immune priming is partially sexually dimorphic in adolescent mouse offspring exposed to maternal high-fat diet. J Neuroinflamm. 2020;17:264. source

      The Discussion (page unavailable) says neuroendocrine receptors can modulate microglial functions and that microglia express these receptors differently between sexes. That supports hormonal regulation and sex-related differences, but it does not establish that sex hormones specifically have a strong effect on microglia. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
    • cites [17] Schwarz JM, Sholar PW, Bilbo SD. Sex differences in microglial colonization of the developing rat brain. J Neurochem. 2012;120:948–63. source

      The Discussion reports substantial sex differences in microglial number and morphology in developing rats and proposes that early differences may be induced by sex hormones. It also says the hormonal mechanism is unclear, so it does not establish the claim that microglia are highly affected by sex hormones. Page numbers are unavailable in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [18] Lenz KM, Nugent BM, Haliyur R, McCarthy MM. Microglia are essential to masculinization of Brain and Behavior. J Neurosci. 2013;33:2761–72. source
    • cites [19] Doyle HH, Eidson LN, Sinkiewicz DM, Murphy AZ. Sex differences in Microglia Activity within the Periaqueductal Gray of the rat: a potential mechanism driving the Dimorphic effects of Morphine. J Neurosci. 2017;37:3202–14. source
    • cites [20] Weinhard L, Neniskyte U, Vadisiute A, di Bartolomei G, Aygün N, Riviere L, et al. Sexual dimorphism of microglia and synapses during mouse postnatal development. Dev Neurobiol. 2018;78:618–26. source

      The Introduction identifies microglia as resident immune cells of the brain, and the Results report sex differences in their development. Neither those passages nor the passages retrieved for “sex hormones” and “hormone” establish that sex hormones highly affect microglia; the paper does not test a hormonal effect. Our copy provides section labels but no page numbers. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
  • Premisecitation

    Sex differences extend to individual cells within the brain parenchyma, including microglia.

    “Sex differences also extend to individual cells within the brain parenchyma, including microglia [3, 14, 15].”
    Quote in the paperSubstantial claim3 of 3 sources checked
    • cites [3] Alfano V, Cavaliere C, Di Cecca A, Ciccarelli G, Salvatore M, Aiello M, et al. Sex differences in functional brain networks involved in interoception: an fMRI study. Front Neurosci. 2023;17:1130025. source

      The Introduction (page unavailable) reports sex differences in brain cytoarchitecture and regional structure. It does not say that these differences extend to individual cells in the brain parenchyma or mention microglia; searches for those terms found no supporting passage. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [14] Hui CW, Vecchiarelli HA, Gervais É, Luo X, Michaud F, Scheefhals L, et al. Sex differences of Microglia and synapses in the hippocampal dentate gyrus of adult mouse offspring exposed to maternal Immune activation. Front Cell Neurosci. 2020;14:558181. source
    • cites [15] Loiola RA, Wickstead ES, Solito E, McArthur S. Estrogen promotes pro-resolving microglial behavior and phagocytic cell clearance through the actions of annexin A1. Front Endocrinol (Lausanne). 2019;10:420. source

      The Discussion (page unavailable) describes sex differences in CNS inflammatory diseases and reports that estrogen modulates microglial behavior. That supports a sex-hormone effect at the cellular level, but the paper does not establish a difference between male and female microglia; its primary microglial cultures came from female mice only (Materials and Methods, page unavailable). (LLM, conf=0.82)

      Experimental — accuracy not yet measured
  • Premisecitation

    Microglia are highly affected by hormonal and transcriptional changes.

    “As microglia are highly affected by hormonal and transcriptional changes, female and male wild-type mice (WT XX and WT XY) were also used for validation [10, 13, 18, 44, 50].”
    Quote in the paperSubstantial claim1 of 5 sources checked
    • cites [10] Bobotis BC, Braniff O, Gargus M, Akinluyi ET, Awogbindin IO, Tremblay M-È. Sex differences of microglia in the healthy brain from embryonic development to adulthood and across lifestyle influences. Brain Res Bull. 2023;202:110752. source
    • cites [13] Spritzer MD, Galea LAM. Testosterone and dihydrotestosterone, but not estradiol, enhance survival of new hippocampal neurons in adult male rats. Dev Neurobiol. 2007;67:1321–33. source
    • cites [18] Lenz KM, Nugent BM, Haliyur R, McCarthy MM. Microglia are essential to masculinization of Brain and Behavior. J Neurosci. 2013;33:2761–72. source

      The Results section on hormonal dependence reports that estradiol treatment changed microglial morphology in the neonatal preoptic area, supporting the hormonal part of the claim. The cited passages do not establish that microglia are highly affected by transcriptional changes, so that part is unsupported. No page numbers are available in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [44] Guneykaya D, Ivanov A, Hernandez DP, Haage V, Wojtas B, Meyer N, et al. Transcriptional and Translational Differences of Microglia from male and female brains. Cell Rep. 2018;24:2773–e27836. source
    • cites [50] Bordeleau M, Carrier M, Luheshi GN, Tremblay M-È. Microglia along sex lines: from brain colonization, maturation and function, to implication in neurodevelopmental disorders. Semin Cell Dev Biol. 2019;94:152–63. source
  • Classified as probably not a substantial claim. 28
  • May combine two claims. 42

  • Classified as probably not a substantial claim.

    Premisecitation

    The brain exhibits clear structural and functional differences based on sex.

    “The brain exhibits clear structural and functional differences based on sex [1–3].”
    Quote in the paperSubstantial claim3 of 3 sources checked
    • cites [1] DeCasien AR, Guma E, Liu S, Raznahan A. Sex differences in the human brain: a roadmap for more careful analysis and interpretation of a biological reality. Biology Sex Differences. 2022;13:43. source

      The Conclusions report reproducible sex differences in regional brain anatomy, but qualify them as small-to-moderate differences in the means of largely overlapping distributions. Part 4, “Framing and interpreting the results,” says that describing anatomical differences is distinct from establishing their functional implications, which remain uncertain. The source therefore supports the structural part of the claim, but not an unqualified assertion of clear functional differences. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [2] Nojima T, Rings A, Allen AM, Otto N, Verschut TA, Billeter J-C, et al. A sex-specific switch between visual and olfactory inputs underlies adaptive sex differences in behavior. Curr Biol. 2021;31:1175–e11916. source
    • cites [3] Alfano V, Cavaliere C, Di Cecca A, Ciccarelli G, Salvatore M, Aiello M, et al. Sex differences in functional brain networks involved in interoception: an fMRI study. Front Neurosci. 2023;17:1130025. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Dysregulation of microglial functions is associated with several health concerns that often show sex prevalences, including Alzheimer's disease (more prevalent among females), Parkinson's disease (more male-prevalent), and various other neurodevelopmental, neuropsychiatric and neurodegenerative disorders.

    “Dysregulation of microglial functions is associated with several health concerns that often show sex prevalences, not only affecting Alzheimer’s disease, which shows more prevalence among females, and Parkinson’s disease, more male-prevalent, but also including various other neurodevelopmental, neuropsychiatric and neurodegenerative disorders [38–43].”
    Quote in the paperNot a substantial claim3 of 6 sources checked
    • cites [38] Bisht K, Sharma KP, Lecours C, Sánchez MG, El Hajj H, Milior G, et al. Dark microglia: a new phenotype predominantly associated with pathological states. Glia. 2016;64:826–39. source

      Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
    • cites [39] Anderson AG, Rogers BB, Loupe JM, Rodriguez-Nunez I, Roberts SC, White LM, et al. Single nucleus multiomics identifies ZEB1 and MAFB as candidate regulators of Alzheimer’s disease-specific cis-regulatory elements. Cell Genomics. 2023;3:100263. source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
    • cites [40] Lavisse S, Goutal S, Wimberley C, Tonietto M, Bottlaender M, Gervais P, et al. Increased microglial activation in patients with Parkinson disease using [18F]-DPA714 TSPO PET imaging. Parkinsonism Relat Disord. 2021;82:29–36. source
    • cites [41] Bovenzi R, Sancesario GM, Conti M, Grillo P, Cerroni R, Bissacco J, et al. Sex hormones differentially contribute to Parkinson disease in males: a multimodal biomarker study. Eur J Neurol. 2023;30:1983–90. source

      The Introduction states that Parkinson disease is more prevalent in males, supporting the sex-prevalence portion relevant to this paper. The passages on neuroinflammation do not establish the sentence’s association between microglial dysfunction and Parkinson disease; the paper’s focus is sex hormones and PD biomarkers. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [42] Lopez-Lee C, Torres ERS, Carling G, Gan L. Mechanisms of sex differences in Alzheimer’s disease. Neuron. 2024;112:1208–21. source
    • cites [43] Doss PMIA, Umair M, Baillargeon J, Fazazi R, Fudge N, Akbar I, et al. Male sex chromosomal complement exacerbates the pathogenicity of Th17 cells in a chronic model of central nervous system autoimmunity. Cell Rep. 2021;34:108833. source

  • May combine two claims.

    Premisecitation

    Microglia can express receptors for ovarian hormones such as estradiol, and for testicular hormones like testosterone.

    “Notably, microglia can express receptors for ovarian hormones such as estradiol, and for testicular hormones like testosterone [35–37].”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [35] García-Ovejero D, Veiga S, García-Segura LM, Doncarlos LL. Glial expression of estrogen and androgen receptors after rat brain injury. J Comp Neurol. 2002;450:256–71. source
    • cites [36] Habib P, Dreymueller D, Ludwig A, Beyer C, Dang J. Sex steroid hormone-mediated functional regulation of microglia-like BV-2 cells during hypoxia. J Steroid Biochem Mol Biol. 2013;138:195–205. source
    • cites [37] Wu W, Tan X, Dai Y, Krishnan V, Warner M, Gustafsson J-Å. Targeting estrogen receptor β in microglia and T cells to treat experimental autoimmune encephalomyelitis. Proc Natl Acad Sci. 2013;110:3543–8. source

      The Results section (page not provided) reports that mouse microglia express estrogen receptor β, supporting the estradiol-receptor part of the claim. The passages retrieved for testosterone and androgen receptors do not establish that microglia express receptors for testicular hormones, so this source supports only part of the sentence. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Microglia are essential for brain development and play a crucial role in preserving CNS health and maintaining homeostatic balance when challenged by infectious or inflammatory cues.

    “These cells are essential for brain development and play a crucial role in preserving the health of the CNS, maintaining its homeostatic balance when challenged by infectious or inflammatory cues [21, 22].”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [21] Tremblay M-È. Microglial functional alteration and increased diversity in the challenged brain: insights into novel targets for intervention. Brain Behav Immun - Health. 2021;16:100301. source

      The Introduction (page unavailable) describes microglia as crucial during development, and the Abstract says they actively maintain CNS health. But the Abstract and “Microglial response to environmental risk factors” (pages unavailable) say infection can compromise microglial functions; they do not establish that microglia maintain homeostatic balance when challenged by infectious or inflammatory cues. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [22] Tremblay M-È, Majewska AK. Ultrastructural Analyses of Microglial Interactions with synapses. Methods Mol Biol. 2019;2034:83–95. source

      The Introduction (page unavailable) discusses microglial behavior in normal brain development, and the Abstract describes their roles in synaptic pruning and stripping. The paper does not establish that microglia are essential for development or say that they preserve CNS health and maintain homeostasis in response to infectious or inflammatory cues. (LLM, conf=0.78)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Various factors, such as genetics, epigenetics, and hormonal influences, contribute to sex differences in the brain.

    “It is widely acknowledged that various factors, such as genetics, epigenetics, and hormonal influences, contribute to these sex differences [4].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [4] Ratnu VS, Emami MR, Bredy TW. Genetic and epigenetic factors underlying sex differences in the regulation of gene expression in the brain. J Neurosci Res. 2017;95:301–10. source

  • Classified as probably not a substantial claim.

    Premisecitation

    Biological sex is determined by sex chromosomes and sex hormones.

    “Biological sex is determined by sex chromosomes and sex hormones [8, 9].”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [8] Harley R, Goodfellow VN. The biochemical role of SRY in sex determination. Mol Reprod Dev. 1994;39:184–93. source
    • cites [9] Corre C, Friedel M, Vousden DA, Metcalf A, Spring S, Qiu LR, et al. Separate effects of sex hormones and sex chromosomes on brain structure and function revealed by high-resolution magnetic resonance imaging and spatial navigation assessment of the four core genotype mouse model. Brain Struct Funct. 2016;221:997–1016. source

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Sex determination is led by genes on sex chromosomes and release of sex hormones, especially androgens and estrogens, primarily from gonads, exerting effects on body, brain, and behavior.

    “This process is led by genes located on the sex chromosomes and the release of sex hormones, especially androgens and estrogens, coming primarily from the gonads and exerting effects on the body, brain, and behavior [10–13].”
    Quote in the paperSubstantial claim2 of 4 sources checked
    • cites [10] Bobotis BC, Braniff O, Gargus M, Akinluyi ET, Awogbindin IO, Tremblay M-È. Sex differences of microglia in the healthy brain from embryonic development to adulthood and across lifestyle influences. Brain Res Bull. 2023;202:110752. source
    • cites [11] Bramble MS, Lipson A, Vashist N, Vilain E. Effects of chromosomal sex and hormonal influences on shaping sex differences in brain and behavior: lessons from cases of disorders of sex development. J Neurosci Res. 2017;95:65–74. source
    • cites [12] Hiort O. The differential role of androgens in early human sex development. BMC Med. 2013;11:152. source

      The Introduction’s developmental-aspects section links X- and Y-chromosome genes to sexual development, describes hormones secreted mainly by the testes, and reports sex-steroid effects on the body, brain, and behavior. The paper specifically discusses androgens, but the cited passages do not substantiate the claim’s added emphasis on estrogens. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [13] Spritzer MD, Galea LAM. Testosterone and dihydrotestosterone, but not estradiol, enhance survival of new hippocampal neurons in adult male rats. Dev Neurobiol. 2007;67:1321–33. source

  • May combine two claims.

    Premisecitation

    During normal physiological conditions, adult male mice tend to exhibit denser microglia in the hippocampus, cortex, and amygdala, whereas female rats typically display longer and more extensively branched microglial processes in the prefrontal cortex around adolescence.

    “During normal physiological conditions, it has been shown that adult male mice tend to exhibit denser microglia in the hippocampus, cortex, and amygdala, whereas female rats typically display longer and more extensively branched microglial processes in the prefrontal cortex around adolescence, indicating possible differences in microglial surveillance between sexes, brain regions and time points [”
    Quote in the paperSubstantial claim2 of 3 sources checked
    • cites [44] Guneykaya D, Ivanov A, Hernandez DP, Haage V, Wojtas B, Meyer N, et al. Transcriptional and Translational Differences of Microglia from male and female brains. Cell Rep. 2018;24:2773–e27836. source
    • cites [45] Villa A, Gelosa P, Castiglioni L, Cimino M, Rizzi N, Pepe G, et al. Sex-specific features of Microglia from Adult mice. Cell Rep. 2018;23:3501–11. source

      Split into 2 atoms — 0 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 2 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
    • cites [46] Gildawie KR, Orso R, Peterzell S, Thompson V, Brenhouse HC. Sex differences in prefrontal cortex microglia morphology: impact of a two-hit model of adversity throughout development. Neurosci Lett. 2020;738:135381. source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Microglia promote and assist various processes within the CNS, closely interacting with neurons, other glial cells, the neurovascular unit and the extracellular matrix.

    “Microglia promote and assist with various processes within the CNS, closely interacting with neurons, other glial cells, the neurovascular unit and the extracellular matrix.”
    Quote in the paperNot a substantial claim2 of 6 sources checked
    • cites [23] Venturino A, Schulz R, De Jesús-Cortés H, Maes ME, Nagy B, Reilly-Andújar F, et al. Microglia enable mature perineuronal nets disassembly upon anesthetic ketamine exposure or 60-Hz light entrainment in the healthy brain. Cell Rep. 2021;36:109313. source

      The Results section (“Microglia interact with Pvalb+ neurons and remodel PNN”) documents interactions with neurons, and the Discussion (“Ketamine induces microglia-mediated PNN remodeling”) describes microglial interactions with perineuronal nets, a form of extracellular matrix. Our copy does not establish the claimed close interactions with other glial cells or the neurovascular unit, so it supports only part of the broad statement. Page numbers were not available in the indexed passages. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [24] Nguyen PT, Dorman LC, Pan S, Vainchtein ID, Han RT, Nakao-Inoue H, et al. Microglial remodeling of the Extracellular Matrix promotes synapse plasticity. Cell. 2020;182:388–e40315. source

      The Introduction (page unavailable) describes microglial contact with neuronal spines and astrocyte-derived IL-33 driving microglial synapse engulfment. The Discussion (page unavailable) describes microglial remodeling of the extracellular matrix. These passages support several interactions in the claim, but our copy does not establish microglial interaction with the neurovascular unit. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [25] Filipello F, Morini R, Corradini I, Zerbi V, Canzi A, Michalski B, et al. The Microglial Innate Immune receptor TREM2 is required for synapse elimination and normal brain connectivity. Immunity. 2018;48:979–e9918. source
    • cites [26] Jiang T, Zhang Y-D, Gao Q, Zhou J-S, Zhu X-C, Lu H, et al. TREM1 facilitates microglial phagocytosis of amyloid beta. Acta Neuropathol. 2016;132:667–83. source
    • cites [27] St-Pierre M-K, Bordeleau M, Tremblay M-È. Visualizing dark microglia. Methods Mol Biol. 2019;2034:97–110. https://doi.org/10.1007/978-1-4939-9658-2_8. source
    • cites [28] St-Pierre M-K, Carrier M, Lau V, Tremblay M-È. Investigating microglial ultrastructural alterations and intimate relationships with neuronal stress, dystrophy, and degeneration in mouse models of Alzheimer’s Disease. Methods Mol Biol. 2022;2515:29–58. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Microglial colonization precedes a hormonal surge in the brain, with androgens and estrogens peaking at around E17.5-18.

    “This precedes a hormonal surge in the brain, with androgens and estrogens peaking at around E17.5–18 [29–34].”
    Quote in the paperNot a substantial claim2 of 6 sources checked
    • cites [29] Juraska JM, Sisk CL, DonCarlos LL. Sexual differentiation of the adolescent rodent brain: hormonal influences and developmental mechanisms. Horm Behav. 2013;64:203–10. source
    • cites [30] Alliot F, Godin I, Pessac B. Microglia derive from progenitors, originating from the yolk sac, and which proliferate in the brain. Brain Res Dev Brain Res. 1999;117:145–52. source
    • cites [31] Welsh M, Saunders PTK, Fisken M, Scott HM, Hutchison GR, Smith LB, et al. Identification in rats of a programming window for reproductive tract masculinization, disruption of which leads to hypospadias and cryptorchidism. J Clin Invest. 2008;118:1479–90. source

      The Introduction (page unavailable) discusses fetal testosterone production and mentions brain masculinization in primates, but does not describe a hormonal surge in the rat brain. Figure 3 (page unavailable) reports testicular testosterone concentrations from E15.5 to E21.5, not brain androgen or estrogen peaks. Searches for a prenatal brain hormone peak, estrogens, and microglia found no passage establishing the claimed sequence or E17.5–18 peak. (LLM, conf=0.74)

      Experimental — accuracy not yet measured
    • cites [32] Habert R, Picon R. Testosterone, dihydrotestosterone and estradiol-17 beta levels in maternal and fetal plasma and in fetal testes in the rat. J Steroid Biochem. 1984;21:193–8. source
    • cites [33] Keller D, Erö C, Markram H. Cell densities in the mouse brain: a systematic review. Front Neuroanat. 2018;12:83. source

      The Results section’s subcortical cell-density table reports microglial counts, not when microglia colonize the brain. Searches for E17.5, E18, and an embryonic androgen or estrogen surge found no passage in our copy establishing the claimed timing or sequence; the References mention adult androgen responsiveness but do not address it. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
    • cites [34] Sauer J-F, Bartos M. The role of the dentate gyrus in mnemonic functions. Neuroforum. 2020;26:247–54. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Microglia originate from the embryonic yolk sac, migrate and colonize the brain during early development, around E9.5 in mice.

    “Originating from the embryonic yolk sac, microglia migrate and colonize the brain during early development, around embryonic day (E)9.5 in mice.”
    Quote in the paperNot a substantial claim2 of 6 sources checked
    • cites [29] Juraska JM, Sisk CL, DonCarlos LL. Sexual differentiation of the adolescent rodent brain: hormonal influences and developmental mechanisms. Horm Behav. 2013;64:203–10. source
    • cites [30] Alliot F, Godin I, Pessac B. Microglia derive from progenitors, originating from the yolk sac, and which proliferate in the brain. Brain Res Dev Brain Res. 1999;117:145–52. source
    • cites [31] Welsh M, Saunders PTK, Fisken M, Scott HM, Hutchison GR, Smith LB, et al. Identification in rats of a programming window for reproductive tract masculinization, disruption of which leads to hypospadias and cryptorchidism. J Clin Invest. 2008;118:1479–90. source

      The Introduction discusses fetal reproductive-tract masculinization, and the Figure 6 passage discusses androgen action in rats; neither addresses microglia. Searches for microglia, yolk-sac origin, brain colonization, and E9.5 in mice found no relevant passage in our copy. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
    • cites [32] Habert R, Picon R. Testosterone, dihydrotestosterone and estradiol-17 beta levels in maternal and fetal plasma and in fetal testes in the rat. J Steroid Biochem. 1984;21:193–8. source
    • cites [33] Keller D, Erö C, Markram H. Cell densities in the mouse brain: a systematic review. Front Neuroanat. 2018;12:83. source

      The Introduction describes microglia as a type of glial cell, and the Discussion reports their densities across adult mouse brain regions. Neither those passages nor searches for “yolk sac,” “E9.5,” and embryonic brain colonization yielded a passage addressing microglial origin or when they enter the brain. (LLM, conf=0.77)

      Experimental — accuracy not yet measured
    • cites [34] Sauer J-F, Bartos M. The role of the dentate gyrus in mnemonic functions. Neuroforum. 2020;26:247–54. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Microglia regulate axonal myelination, synaptic pruning, vasculature repair, and clearance of debris and toxic substances.

    “These cells not only regulate axonal myelination, but also contribute to synaptic pruning, vasculature repair, and clearance of debris and toxic substances, among other important physiological roles [23–28].”
    Quote in the paperNot a substantial claim2 of 6 sources checked
    • cites [23] Venturino A, Schulz R, De Jesús-Cortés H, Maes ME, Nagy B, Reilly-Andújar F, et al. Microglia enable mature perineuronal nets disassembly upon anesthetic ketamine exposure or 60-Hz light entrainment in the healthy brain. Cell Rep. 2021;36:109313. source

      The Results section reports microglial uptake of perineuronal-net fragments after ketamine exposure, but does not establish the listed roles. Searches of our copy for myelination, synaptic pruning, vasculature repair, and clearance of debris or toxic substances found no passage addressing those claims. No page numbers were available in our copy. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
    • cites [24] Nguyen PT, Dorman LC, Pan S, Vainchtein ID, Han RT, Nakao-Inoue H, et al. Microglial remodeling of the Extracellular Matrix promotes synapse plasticity. Cell. 2020;182:388–e40315. source

      The Introduction (page unavailable) says microglia engulf synapse components, supporting their role in synaptic pruning. The Discussion, under “Microglia Remodel the Brain ECM” (page unavailable), asks whether microglia remodel myelin rather than establishing that they regulate myelination. The passages do not substantiate vasculature repair or clearance of debris and toxic substances. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [25] Filipello F, Morini R, Corradini I, Zerbi V, Canzi A, Michalski B, et al. The Microglial Innate Immune receptor TREM2 is required for synapse elimination and normal brain connectivity. Immunity. 2018;48:979–e9918. source
    • cites [26] Jiang T, Zhang Y-D, Gao Q, Zhou J-S, Zhu X-C, Lu H, et al. TREM1 facilitates microglial phagocytosis of amyloid beta. Acta Neuropathol. 2016;132:667–83. source
    • cites [27] St-Pierre M-K, Bordeleau M, Tremblay M-È. Visualizing dark microglia. Methods Mol Biol. 2019;2034:97–110. https://doi.org/10.1007/978-1-4939-9658-2_8. source
    • cites [28] St-Pierre M-K, Carrier M, Lau V, Tremblay M-È. Investigating microglial ultrastructural alterations and intimate relationships with neuronal stress, dystrophy, and degeneration in mouse models of Alzheimer’s Disease. Methods Mol Biol. 2022;2515:29–58. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The hippocampus is an important brain region involved in consolidation and storage of long-term memories, cognition and emotional processing.

    “The hippocampus is an important brain region involved in the consolidation and storage of long-term memories, cognition and emotional processing [54, 55].”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [54] Fanselow MS, Dong H-W. Are the dorsal and ventral Hippocampus functionally distinct structures? Neuron. 2010;65:7–19. source

      The Memory & Cognition and Emotion sections link the hippocampus to memory, cognition, and emotional function. The Anatomic Connectivity section suggests a role in memory consolidation, but attributes long-term retention of contextual fear memories to the perirhinal and postrhinal cortices; our copy does not establish that the hippocampus stores long-term memories. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [55] Jinno S, Klausberger T, Marton LF, Dalezios Y, Roberts JDB, Fuentealba P, et al. Neuronal diversity in GABAergic Long-Range projections from the Hippocampus. J Neurosci. 2007;27:8790–804. source

      The Diversity of GABAergic projection cell types section (page unavailable) places hippocampal projections within a temporal episodic memory system, offering broad support for a role in memory. The Introduction also discusses cognitive representations, but the copy does not say that the hippocampus consolidates or stores long-term memories or is involved in emotional processing. (LLM, conf=0.83)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    Images were blinded to experimental groups for density and morphology analyses.

    “The images were blinded to the experimental groups and analysed using Fiji (NIH; v.1.53), as previously reported [56, 64].”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [56] De Felice E, Gonçalves de Andrade E, Golia MT, González Ibáñez F, Khakpour M, Di Castro MA, et al. Microglial diversity along the hippocampal longitudinal axis impacts synaptic plasticity in adult male mice under homeostatic conditions. J Neuroinflamm. 2022;19:292. source

      The Methods section (Light and electron microscopy; page unavailable) says the images used for density analysis were blindly analyzed. It describes a separate morphology analysis but does not say whether that analysis was blinded to experimental groups. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [64] González Ibanez F, Picard K, Bordeleau M, Sharma K, Bisht K, Tremblay M-È. Immunofluorescence staining using IBA1 and TMEM119 for microglial density, morphology and peripheral myeloid cell infiltration analysis in mouse brain. J Vis Exp. 2019. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The hippocampus is rich in estradiol receptors where neurons locally synthesize estrogen and testosterone during adulthood, particularly pyramidal neurons of CA1 and granule cells of DG.

    “This area is also rich in estradiol receptors where neurons locally synthesize estrogen and testosterone during adulthood, particularly the pyramidal neurons of the CA1 and the granule cells of the DG [51–53].”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites [51] Hojo Y, Higo S, Kawato S, Hatanaka Y, Ooishi Y, Murakami G, et al. Hippocampal synthesis of sex steroids and corticosteroids: essential for modulation of synaptic plasticity. Front Endocrinol (Lausanne). 2011;2:43. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3356120/ source
    • cites [52] Hojo Y, Murakami G, Mukai H, Higo S, Hatanaka Y, Ogiue-Ikeda M, et al. Estrogen synthesis in the brain—role in synaptic plasticity and memory. Mol Cell Endocrinol. 2008;290:31–43. source
    • cites [53] Ooishi Y, Kawato S, Hojo Y, Hatanaka Y, Higo S, Murakami G, et al. Modulation of synaptic plasticity in the hippocampus by hippocampus-derived estrogen and androgen. J Steroid Biochem Mol Biol. 2012;131:37–51. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Ultrastructural analyses were performed using QuPath on images blinded to both animal and group.

    “The microglial ultrastructural analyses was performed using QuPath (v.0.4.4) [71] on images blinded to both animal and group, following an adaptation from our previous work [56, 64].”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [71] Bankhead P, Loughrey MB, Fernández JA, Dombrowski Y, McArt DG, Dunne PD, et al. QuPath: open source software for digital pathology image analysis. Sci Rep. 2017;7:16878. source
    • cites [56] De Felice E, Gonçalves de Andrade E, Golia MT, González Ibáñez F, Khakpour M, Di Castro MA, et al. Microglial diversity along the hippocampal longitudinal axis impacts synaptic plasticity in adult male mice under homeostatic conditions. J Neuroinflamm. 2022;19:292. source

      The Methods section (Light and electron microscopy; page unavailable) says the electron-microscopy analysis used QuPath and was blinded to animal and hippocampal pole. It supports the QuPath method and animal blinding, but specifies hippocampal pole rather than blinding to a general experimental group. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [64] González Ibanez F, Picard K, Bordeleau M, Sharma K, Bisht K, Tremblay M-È. Immunofluorescence staining using IBA1 and TMEM119 for microglial density, morphology and peripheral myeloid cell infiltration analysis in mouse brain. J Vis Exp. 2019. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Peripheral monocytes and macrophages were recently shown to infiltrate the brain during normal physiological conditions, in the first postnatal weeks, but their roles in the healthy adult brain have remained undetermined.

    “Peripheral monocytes and macrophages were recently shown to infiltrate the brain during normal physiological conditions, in the first postnatal weeks, but their roles in the healthy adult brain have remained undetermined [66].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [66] Carrier M, Robert M-È, St-Pierre M-K, Ibáñez FG, Gonçalves de Andrade E, Laroche A, et al. Bone marrow-derived myeloid cells transiently colonize the brain during postnatal development and interact with glutamatergic synapses. iScience. 2024;27:110037. source

      The Abstract reports transient bone marrow-derived myeloid cells in the healthy brain during early postnatal development, supporting the first part of the claim. The Results report a lack of FLT3+ cells in adult whole-brain isolates, but the paper does not establish the broader claim that peripheral monocytes’ and macrophages’ roles in the healthy adult brain remain undetermined. (LLM, conf=0.83)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Cells portraying smaller cellular somas in addition to extensive and well-branched processes are usually linked to a surveillant state of microglia, whereas the shrinkage of processes and bigger somas are usually linked to reactive states.

    “Cells portraying smaller cellular somas in addition to extensive and well-branched processes are usually linked to a surveillant state of microglia, whereas the shrinkage of processes and bigger somas are usually linked to reactive states [83–86].”
    Quote in the paperNot a substantial claim4 of 4 sources checked
    • cites [83] Paolicelli RC, Sierra A, Stevens B, Tremblay M-E, Aguzzi A, Ajami B, et al. Microglia states and nomenclature: a field at its crossroads. Neuron. 2022;110:3458–83. source

      The “(RE)DEFINING MICROGLIAL STATES” section says that microglial processes scan the brain parenchyma in the mature healthy CNS, and “MICROGLIAL STATES IN THE DISEASED CNS” says microglia change morphology in response to challenges. Neither passage specifies that surveillant cells have smaller somas and extensively branched processes, or that reactive cells generally have larger somas and shrunken processes. Page numbers were not available in our copy. (LLM, conf=0.83)

      Experimental — accuracy not yet measured
    • cites [84] Colombo G, Cubero RJA, Kanari L, Venturino A, Schulz R, Scolamiero M, et al. A tool for mapping microglial morphology, morphOMICs, reveals brain-region and sex-dependent phenotypes. Nat Neurosci. 2022;25:1379–93. source

      The Discussion (page unavailable) links ramified microglia with surveillance, and the Results section on 5xFAD (page unavailable) reports loss of high-level branches in disease-associated microglia. The paper does not establish the claimed smaller-versus-bigger soma sizes or a general rule that reactive microglia have shrunken processes. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [85] Zanier ER, Fumagalli S, Perego C, Pischiutta F, De Simoni M-G. Shape descriptors of the never resting microglia in three different acute brain injury models in mice. Intensive Care Med Experimental. 2015;3:7. source
    • cites [86] Maras PM, Hebda-Bauer EK, Hagenauer MH, Hilde KL, Blandino P, Watson SJ, et al. Differences in microglia morphological profiles reflect divergent emotional temperaments: insights from a selective breeding model. Transl Psychiatry. 2022;12:1–11. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Classically, denser microglial populations might indicate a higher level of surveillance of the brain parenchyma, although this feature has also been reported to precede a reactive state.

    “Classically, denser microglial populations might indicate a higher level of surveillance of the brain parenchyma, although this feature has also been reported to precede a reactive state [79].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [79] Rodríguez JJ, Witton J, Olabarria M, Noristani HN, Verkhratsky A. Increase in the density of resting microglia precedes neuritic plaque formation and microglial activation in a transgenic model of Alzheimer’s disease. Cell Death Dis. 2010;1:e1–1. source

      The Discussion (page unavailable) reports that increased resting-microglial density in an Alzheimer’s mouse model preceded plaque formation and microglial activation. The introductory passage (page unavailable) says resting microglia scan their surroundings, but the paper does not establish that denser populations provide a higher level of surveillance. (LLM, conf=0.84)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    Increased contacts with pre- and post-synaptic elements in the WT group might indicate enhanced synapse plasticity and maintenance.

    “Increased contacts with pre- and post-synaptic elements in the WT group might indicate enhanced synapse plasticity and maintenance, as microglia are known to constantly modulate synapses during normal physiological conditions [14, 24, 87].”
    Quote in the paperNot a substantial claim3 of 3 sources checked
    • cites [14] Hui CW, Vecchiarelli HA, Gervais É, Luo X, Michaud F, Scheefhals L, et al. Sex differences of Microglia and synapses in the hippocampal dentate gyrus of adult mouse offspring exposed to maternal Immune activation. Front Cell Neurosci. 2020;14:558181. source
    • cites [24] Nguyen PT, Dorman LC, Pan S, Vainchtein ID, Han RT, Nakao-Inoue H, et al. Microglial remodeling of the Extracellular Matrix promotes synapse plasticity. Cell. 2020;182:388–e40315. source
    • cites [87] Šišková Z, Tremblay M-È. Microglia and synapse: interactions in health and neurodegeneration. Neural Plast. 2013;2013:425845. source

  • May combine two claims.

    Findingown data

    In the Rad, there were significant main effects of sex chromosomes and sex hormones on microglial soma area, with a significant interaction between them.

    “In the Rad (Fig. 2G), we observed both chromosomal (F(2, 24) = 12.37, ***p = 0.0002) and hormonal main effects on microglial soma area (F(1, 24) = 14.66, ***p = 0.0008), with a significant interaction between them (F(2, 24) = 7.845, **p = 0.0024).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    When analysing the numbers of healthy ER/Golgi cisternae, there was a main chromosome effect and a sex chromosome versus hormone interaction.

    “When analysing the numbers of healthy ER/Golgi cisternae (Fig. 3I), we found a main chromosome effect (F(2, 266) = 20.04, ****p < 0.0001) and a sex chromosome versus hormone interaction (F(2, 266) = 4.482, *p = 0.0122).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In the LMol, there was a strong hormone effect and a lighter chromosomal effect on soma circularity, with an interaction, whereby overall testes animals tended to display more circular somas than ovary animals.

    “Similarly in the LMol (Fig. 2K), for soma circularity, we found a strong hormone effect (F(1, 24) = 27.24, ****p < 0.0001) and lighter chromosomal effect for the soma circularity (F(2, 24) = 6.898, **p = 0.0043), with an interaction between them (F(2, 24) = 4.379, *p = 0.0239), whereby overall testes animals tended to display more circular somas then ovary animals.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Microglial extracellular digestion was affected by hormones but mainly by chromosomes.

    “Similarly, microglial extracellular digestion (Fig. 3K) was affected by hormones (F(1, 264) = 4.420, *p = 0.0365), but mainly by chromosomes (F(2, 264) = 12.27, ****p < 0.0001).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    FCG XX microglia were less dense than Tg XYSry mice, showing a sex difference in density.

    “In contrast, microglia in the FCG XX genotype were less dense than in Tg XYSry mice, showing a sex difference in density.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In the PoDG, Tg XYSry showed a more elongated microglial arborization shape, while Tg XXSry displayed an increase in circular morphology.

    “In the PoDG (Fig. 2U), there was a sex chromosome versus hormone interaction (F(2, 24) = 7.168, **p = 0.0036), where again the Tg XYSry genotype showed a more elongated microglial arborization shape, while the Tg XXSry genotype displayed an increase in circular morphology (Tg XYSry 0.4 ± 0.0 versus Tg XXSry 0.5 ± 0.0, *p = 0.0240, and XX 0.4 ± 0.1, *p = 0.0306).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In the Rad and PoDG, there were strong sex hormone effects on soma circularity, with hormonally male animals having a more circular soma and hormonally female animals a more elongated soma.

    “In the Rad and PoDG (Fig. 2J and L), we obtained strong sex hormone effects (respectively, F(1, 24) = 37.78, ****p < 0.0001 and F(1, 24) = 36.92, ****p < 0.0001) in the circularity of the soma, where, overall, hormonally male animals had a more circular soma, and hormonally female animals a more elongated soma.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    We observed a decrease in microglial density in the FCG XX genotype compared to WT female mice in the CA1 Rad and CA1 LMol, as well as decreased soma area and increased soma circularity, particularly in the LMol.

    “We further observed a decrease in microglial density in the FCG XX genotype compared to WT female mice in the CA1 Rad and CA1 LMol, as well as decreased soma area and increased soma circularity, particularly in the LMol.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Microglial tertiary lysosomes showed a sex chromosome versus hormone interaction, where WT XX mice had more microglial tertiary lysosomes build up than WT XY mice.

    “Lastly, microglial tertiary lysosomes (Fig. 3Q) showed a sex chromosome versus hormone interaction (F(2, 266) = 4.844, **p = 0.0086), where interestingly, WT XX mice had more microglial tertiary lysosomes build up than WT XY mice (WT XY 0.1 ± 0.0 versus WT XX 0.6 ± 0.1, *p = 0.0125).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Microglial morphology was shaped by the interaction of sex hormones and chromosomes in the CA1 Rad and CA1 LMol, with hormonal effects being predominant in the PoDG.

    “Moreover, we found that microglial morphology was shaped by the interaction of sex hormones and chromosomes in the CA1 Rad and CA1 LMol, with hormonal effects being predominant in the PoDG.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In the LMol, there was a main hormone effect and a chromosome effect on microglial soma solidity with a significant interaction.

    “Similarly, in the LMol (Fig. 2N), we also found a main hormone effect for microglial soma solidity (F(1, 24) = 17.24, ***p = 0.0004) with the addition of a chromosome effect (F(2, 24) = 5.396, *p = 0.0116) with a significant interaction (F(2, 24) = 3.677, *p = 0.0404).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    FCG XX mice exhibited a higher NND, while WT XX microglia showed a reduction of their NND.

    “Correspondingly, FCG XX mice exhibited a higher NND, while WT XX microglia showed a reduction of their NND.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The abundance of dystrophic mitochondria in microglial cell bodies showed a main effect of chromosomes and sex hormones, with microglia from testes animals having overall higher counts.

    “The abundance of dystrophic mitochondria (Fig. 3L; presenting abnormal cristae structure or vacuoles) in microglial cell bodies also showed a main effect of chromosomes (F(2, 266) = 3.087, *p = 0.0473) and sex hormones (F(1, 266) = 6.911, **p = 0.0091), with microglia from testes animals having overall higher counts of this altered organelle.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    We observed increased infiltration of Iba1+/TMEM119− myeloid cells in the CA1 LMol in the FCG XX group compared to the WT XX, Tg XXSry, and Tg XYSry, and overall slightly higher levels in animals with ovaries.

    “Furthermore, we have observed an increased infiltration of Iba1+/TMEM119− myeloid cells in the CA1 LMol in the FCG XX group compared to the WT XX, Tg XXSry, and Tg XYSry, and, overall slightly higher levels in animals with ovaries.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In the Rad and LMol, there was a clear interaction between sex hormones and chromosomes, while in the PoDG, the effects were primarily driven by sex hormones.

    “In fact, in the Rad and LMol, there was a clear interaction between sex hormones and chromosomes, while in the PoDG, the effects were primarily driven by sex hormones.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Cytoplasmic membrane circularity and solidity were influenced by sex chromosomes.

    “Similarly, the cytoplasmic membrane circularity and solidity (Fig. 4D and E) were influenced by sex chromosomes (respectively, F(2, 267) = 9.183, ***p = 0.0001 and F(2, 267) = 6.182, **p = 0.0024).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In the LMol, there was a main chromosomal effect and a sex chromosome versus hormone interaction on microglial soma area.

    “In addition, in the LMol (Fig. 2H), there was a main chromosomal effect (F(2, 24) = 10.20, ***p = 0.0006) and a sex chromosome versus hormone interaction (F(2, 24) = 3.836, *p = 0.0358).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Across all examined layers, Tg XXSry displayed increased circularity, while other testes-bearing mice showed a reduction in this feature.

    “Interestingly, across all examined layers, Tg XXSry displayed increased circularity, while other testes-bearing mice showed a reduction in this feature.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The intracisternal distance of ER/Golgi was primarily affected by sex chromosomes and was especially higher in FCG XX mice than in WT XX mice.

    “After measuring the intracisternal distance of these ER/Golgi (Fig. 3J; dilatation > 100 nm), we found that this feature was also primarily affected by sex chromosomes (F(2, 266) = 3.826, *p = 0.0230) and was especially higher in FCG XX mice than in WT XX mice (FCG XX 0.8 ± 0.2 versus WT XX 0.1 ± 0.0, *p = 0.0166).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Microglial contacts with post-synaptic elements relied on a main sex hormone effect, with a weak interaction between sex hormones and chromosomes.

    “However, microglial contacts with post-synaptic elements (Fig. 3H) seemed to rely on a main sex hormone effect (F(1, 266) = 6.397, **p = 0.0120), with a weak interaction between sex hormones and chromosomes (F(2, 266) = 3.246, *p = 0.0405).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In the PoDG, mice with ovaries showed denser microglial populations with overall closer cells compared to mice with testes.

    “In the PoDG, mice with ovaries showed denser microglial populations with overall closer cells compared to mice with testes.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Data normality was assessed with a Shapiro-Wilk test.

    “Data normality was assessed with a Shapiro-Wilk test.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    In total, 271 microglia were analysed, with 10 to 12 cells per animal/group.

    “In total, we analysed 271 microglia, with 10 to 12 cells per animal/group.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    Some data sets were not normally distributed, but ordinary two-way ANOVA tests were still conducted in the absence of a non-parametric version.

    “Of note, some of the data sets were not normally distributed, but in the absence of a non-parametric version, we still conducted the ordinary two-way ANOVA tests.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    No statistical outliers were removed, and no data transformations were performed.

    “No statistical outliers were removed, and no data transformations were performed.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    For microglial morphology analyses, 15 Iba1+/TMEM119+ cells/animal/condition were randomly imaged across at least three different brain sections per animal in each of CA1 Rad, CA1 LMol and PoDG, totalizing 1,350 analysed cells.

    “For the microglial morphology analyses, 15 Iba1+/TMEM119+ cells/animal/condition were randomly imaged across at least three different brain sections per animal in each of the CA1 Rad, CA1 LMol and PoDG (totalizing 1,350 analysed cells).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    Imaging of brain regions was performed with reference to Paxinos and Franklin stereotaxic atlas and subsequently blinded to experimental groups before analyses.

    “Imaging of the brain regions was performed with reference to the Paxinos and Franklin stereotaxic atlas [68] and subsequently blinded to the experimental groups before analyses.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [68] Franklin KBJ, Paxinos G. Paxinos and Franklin’s The mouse brain in stereotaxic coordinates. Fourth edition. Amsterdam: Academic Press, an imprint of Elsevier; 2013.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    In the FCG model, the Sry gene is excised from the Y chromosome and inserted into an autosome, creating four sex chromosome-gonad combinations: XX with ovaries (FCG XX), XY with ovaries (Tg XY−), XX with testes (Tg XXSry), or XY with testes (Tg XYSry).

    “While the sex determining region Y (Sry) gene is required for male testes formation, in this mouse model, this gene is excised from the Y chromosome and inserted into an autosome, creating four sex chromosome-gonad combinations: XX with ovaries (FCG XX), XY with ovaries (Transgenic (Tg) XY−), XX with testes (Tg XXSry), or XY with testes (Tg XYSry) [48].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [48] Lovell-Badge R, Robertson E. XY female mice resulting from a heritable mutation in the primary testis determining gene, Tdy. Development. 1990;109:635–46. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    All studies and procedures were approved by Université Laval and University of Victoria animal care committees, following Canadian Council on Animal Care recommendations.

    “All studies and procedures were approved by the Université Laval (2021-830 and 2023-1372) and the University of Victoria (AUP 2020-013) animal care committees, strictly following the recommendations from the Canadian Council on Animal Care.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    It is possible that the Tg XY− male sire confers an epigenetic signature that might account for the observed phenotypic differences between FCG XX mice and WT females.

    “As is the case for the other FCG progeny, FCG XX mice have a Tg XY− male as a sire; it is possible that this confers them an epigenetic signature that might account for the observed phenotypic differences between FCG XX mice and WT females.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: FCG XX mice are genetically identical to WT females (they do not bear a transgene).

  • May combine two claims.

    Interpretationown data

    Both sex chromosomes and sex hormones appear to influence microglial density and distribution in the Rad and LMol, whereas PoDG has stronger sex hormone effects.

    “Both sex chromosomes and sex hormones appear to influence microglial density and distribution in the Rad and LMol, whereas PoDG has stronger sex hormone effects.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    We are the first to demonstrate a main hormonal effect on microglial density and distribution, particularly in the PoDG, while in the CA1 Rad and CA1 LMol there was an interaction between sex chromosomes and hormones.

    “To our knowledge, we are the first ones to demonstrate this main hormonal effect on microglial density and distribution, particularly in the PoDG, while in the CA1 Rad and CA1 LMol there was an interaction between sex chromosomes and hormones.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing).

    Interpretationreasoning

    We hypothesize that in physiological conditions, the infiltrating cells had easier access from the blood to the hippocampus via the LMol in animals with ovaries.

    “We hypothesize that in physiological conditions, the infiltrating cells had easier access from the blood to the hippocampus via the LMol in animals with ovaries.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    The sex chromosomal by sex hormonal investigation under physiological conditions could aid in providing more targeted therapeutical strategies that consider the patient sex.

    “The sex-dependent differences in microglia at steady-state can impact the susceptibility to a wide variety of neurodevelopmental, neuropsychiatric and neurodegenerative disorders across life, and the sex chromosomal by sex hormonal investigation under physiological conditions could aid in providing more targeted therapeutical strategies that consider the patient sex.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The hippocampal regions examined (CA1 Rad, CA1 LMol, PoDG) are representative of the ventral hippocampus.
54 of 54

  • The paper relies on this without support.

    The precise mechanisms underlying sex differences in microglial density and morphology remain unclear, particularly the influence of sex hormones and chromosomal factors, and whether there is a singular determinant or a combination of factors.

    “Nevertheless, the precise mechanisms underlying these differences in microglial density and morphology between sexes remain unclear, particularly the influence of sex hormones and chromosomal factors, and whether there is a singular determinant or a combination of factors driving these differences.”

  • The paper relies on this without support.

    Sex differences in peripheral myeloid cell infiltration in the healthy adult brain are yet to be uncovered.

    “Similarly, sex differences are yet to be uncovered.”

  • The authors state this as an assumption.

    FCG XX mice are genetically identical to WT females (they do not bear a transgene).

    “This was intriguing because the FCG XX mice do not bear a transgene, and thus should be genetically identical to WT females.”

  • The paper relies on this without support.

    The hippocampal regions examined (CA1 Rad, CA1 LMol, PoDG) are representative of the ventral hippocampus.

    “In conclusion, multiple microglial features, including density and distribution, morphology and, ultrastructure were differently shaped by both sex hormones and sex chromosomes in the ventral hippocampus of adult FCG and WT mice during normal physiological conditions.”
4 of 4

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Abstract reverses the Rad density comparison

    Major

    The abstract says FCG XX microglia are denser than Tg XYSry microglia in the Rad, but the Results report the opposite: 95.8 versus 163.7.

  • Lower solidity is described as less rugous

    Minor

    The discussion says decreased soma solidity makes FCG XX somas less rugous. The paper's own definition says lower solidity indicates greater rugosity.

  • Discussion reverses the LMol soma-circularity comparison

    Minor

    The discussion describes FCG XX soma circularity as increased relative to WT females, but the Results report 0.7 for FCG XX and 0.8 for WT XX.

  • Discussion reverses the LMol soma-area comparison

    Minor

    The discussion describes FCG XX soma area as decreased relative to WT females, whereas the Results report a larger LMol soma area in FCG XX mice: 44.0 versus 36.1.

  • Discussion omits a reported WT sex difference in PoDG density

    Minor

    The discussion says the LMol density difference is the WT density finding and that there are no other WT differences beyond those it lists. The Results also report a large, significant WT XX versus WT XY density difference in the PoDG.

  • Significance symbol does not match the reported p-value

    Minor

    The paper defines ** as p < 0.01, but marks p = 0.0120 with **.

6 of 6

Cites

Flagged first, then by citations

3 of the 139 references couldn’t be matched to a known paper.

Research works printed but not linked: 2

  1. Franklin KBJ, Paxinos G. Paxinos and Franklin’s The mouse brain in stereotaxic coordinates. Fourth edition. Amsterdam: Academic Press, an imprint of Elsevier; 2013.
  2. Bisht K, Sharma KP, Lecours C, Gabriela Sánchez M, El Hajj H, Milior G, et al. Dark microglia: a new phenotype predominantly associated with pathological states. Glia. 2016;64:826–39. · DOI · Paper page

Cited by

Sorted by citations

Related

Authors
Bobotis, B. C., Khakpour, M., Braniff, O., de Andrade, E. G., Gargus, M., Allen, M., Carrier, M., Baillargeon, J., Rangachari, M., & Tremblay, M.-È.
Affiliations
  • University of Victoria (CA)
  • Centre de recherche du CHU de Québec-Université Laval (CA)
  • Université Laval (CA)
  • University of British Columbia (CA)
ORCID
Venue
Journal of Neuroinflammation
Publisher
Springer Science and Business Media LLC
Published
2025-01-24
Volume
22
Issue
1
Pages
18-18
ISSN
1742-2094 (ISSN-L)
DOI
10.1186/s12974-025-03341-6
PMC
PMC11762133
OpenAlex
W4406797545
Semantic Scholar
968a3f65a4a14609907f06df4635ec14ce9cf7ce
Cited by
17
References
139
Citations by year
2026: 13 · 2025: 4
FWCI
5.02
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Neuroinflammation (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
  • PubMed Central (submittedVersion, cc-by-nc-nd)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • Canadian Institutes of Health Research (#PJT191944, #PJT461831)
  • Canada Foundation for Innovation John R. Evans Leaders (#39965)
  • Natural Sciences and Engineering Research Council of Canada Discovery grant (RGPIN-2024-06043)
Topics
  • Life Sciences › Neuroscience › Neurology › Neuroinflammation and Neurodegeneration Mechanisms
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Sex and Gender in Healthcare
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
Keywords
sex differences, microglia, sex chromosomes, sex hormones, gonadal hormones, hippocampus, microglial density, microglial morphology, TMEM119, Iba1, CA1 stratum radiatum, brain immunity, mitochondrial elongation, endoplasmic reticulum dilation, cellular stress
MeSH terms
Animals, Calcium-Binding Proteins, Female, Hippocampus, Male, Mice, Inbred C57BL, Mice, Transgenic, Microfilament Proteins, Sex Characteristics, Sex Chromosomes, Gonadal Steroid Hormones, Microglia, Mice

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-18.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-18.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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