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Cited by 171Neuroendocrine regulation and behaviorBarrier Structure and Function StudiesNeuropeptides and Animal Physiology

Vascular RAGE transports oxytocin into the brain to elicit its maternal bonding behaviour in mice

Open access
Yamamoto, Yasuhiko, Liang, Mingkun, Munesue, Seiichi, Deguchi, Kisaburo, Harashima, Ai, Furuhara, Kazumi, Yuhi, Teruko, Zhong, Jing +22 more·2019·Communications Biology
DOI 10.1038/s42003-019-0325-6PMC PMC6389896
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Abstract

Oxytocin sets the stage for childbirth by initiating uterine contractions, lactation and maternal bonding behaviours. Mice lacking secreted oxcytocin ( Oxt −/− , Cd38 −/− ) or its receptor ( Oxtr −/− ) fail to nurture. Normal maternal behaviour is restored by peripheral oxcytocin replacement in Oxt −/− and Cd38 −/− , but not Oxtr −/− mice, implying that circulating oxcytocin crosses the blood-brain barrier. Exogenous oxcytocin also has behavioural effects in humans. However, circulating polypeptides are typically excluded from the brain. We show that oxcytocin is transported into the brain by receptor for advanced glycation end-products (RAGE) on brain capillary endothelial cells. The increases in oxcytocin in the brain which follow exogenous administration are lost in Ager −/− male mice lacking RAGE, and behaviours characteristic to abnormalities in oxcytocin signalling are recapitulated in Ager −/− mice, including deficits in maternal bonding and hyperactivity. Our findings show that RAGE-mediated transport is critical to the behavioural actions of oxcytocin associated with parenting and social bonding.

AI snapshot

Written from the paper’s full text.

TL;DR

RAGE on brain capillary endothelial cells binds and transports peripheral oxytocin across the blood-brain barrier. Ager−/− mice lack brain oxytocin increases after peripheral oxytocin and show maternal neglect and hyperactivity, which endothelial RAGE re-expression rescues.

Key findings

  • Oxytocin binds RAGE directly: surface plasmon resonance gave an apparent KD of 179 nM for oxytocin binding to immobilised human esRAGE; oxytocin co-eluted with soluble RAGE in human serum and was structurally confirmed by LC-MS/MS. Binding mapped to the RAGE V domain and did not activate NF-κB, Rac1, or Cdc42 signalling.
  • Endothelial RAGE is necessary and sufficient for oxytocin transport into the brain: RAGE knockdown reduced blood-to-brain oxytocin transport in an in vitro BBB model; after subcutaneous oxytocin (30 ng/mouse), CSF oxytocin rose in WT but not Ager−/− male mice, and transgenic endothelial RAGE in Ager−/− mice restored CSF oxytocin. [13C,15N]oxytocin was undetectable in Ager−/− CSF but equivalent in WT and KO+Tg mice.
  • Ager−/− mice recapitulated oxytocin-related behavioural deficits: maternal neglect reduced offspring survival, and endothelial RAGE re-expression rescued survival (63.4% KO+Tg vs 10.5% non-transgenic KO, P < 0.001). c-Fos increased after oxytocin in BNST, mPOA, AHC, and ILS of WT but not Ager−/− mice, and Ager−/− hyperactivity was normalised by intraventricular but not subcutaneous oxytocin.
  • After bilateral common carotid artery occlusion, capillary RAGE increased ~2-fold and exogenous oxytocin increased in CSF of WT but not Ager−/− male mice. The estimated availability of oxytocin in CSF was 0.2% after subcutaneous administration of 30 ng oxytocin in mice.

Methods

  • Mouse models included WT, Ager−/−, endothelial RAGE-transgenic Ager−/− (KO+Tg), and endothelial RAGE-deficient (EC-KO) mice; both male and female mice were used, with behavioural and maternal survival assays, BCCAO, and oxytocin administration by subcutaneous, intravenous, or intranasal routes.
  • Binding and transport were assessed by surface plasmon resonance, plate binding/competition assays, gel permeation chromatography, anti-RAGE affinity chromatography, LC-MS/MS, and an in vitro BBB model using monkey brain capillary endothelial cells with rat pericytes and astrocytes, including RAGE shRNA knockdown, TEER, and Papp calculations.
  • In vivo oxytocin was measured by enzyme immunoassay in serum, cisterna magna CSF, third-ventricle CSF, and microperfusates from amygdala and PVN; c-Fos immunohistochemistry and behavioural tests (light-dark transition, open field) were used, with statistics by t-test, ANOVA, and Kaplan–Meier survival analysis.

Limitations

  • Stated: the exact bioavailability of oxytocin reaching the CNS remains unclear, and findings across studies are inconsistent due to differences in treatment protocols, species, and detection methods. The mechanism by which RAGE transports oxytocin is also unclear, though vesicular endocytosis/transcytosis is proposed.
  • Stated: current experiments provide no evidence for direct intranasal transport via olfactory or trigeminal routes; instead, nasally applied oxytocin may enter the bloodstream and then be transported by RAGE. Oxytocin measurement is also method-dependent, and plasma extraction may lower measured levels.
  • Evident: the maternal behaviour and hyperactivity experiments were conducted largely in male mice, while female mice were used mainly to show RAGE-mediated transport; human data are limited to serum binding/co-elution and do not test behaviour or causality.

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

Integrity signals

Registry

Crossref · 10.1038/s42003-019-0325-6

Cites

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Statistics

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Claims the paper makes

0 of 48 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Oxytocin binds soluble RAGE (esRAGE) with an apparent dissociation constant (KD) of 179 nM.

    “Surface plasmon resonance methods showed concentration-dependent oxytocin binding to immobilised recombinant esRAGE, with an apparent dissociation constant (KD) of 179 nM (Fig. 1c).”
    • Also stated in: § Oxytocin-RAGE interactions · plain
      “Oxytocin-RAGE binding was further confirmed using plate assays where either oxytocin or esRAGE was immobilised, and esRAGE or oxytocin was in solution, respectively (Fig. 1d, e).”
    Quote in the paperSubstantial claim
  • Findingown data

    Endogenous oxytocin and soluble RAGE associate in human circulation.

    “Endogenous oxytocin and soluble RAGE also associate in human circulation.”
    • Also stated in: § Oxytocin-RAGE interactions · plain
      “Using gel permeation chromatography to separate serum proteins based on molecular size, oxytocin immunoreactivity co-eluted with soluble RAGE (Supplementary Figure 1a).”
    • Also stated in: § Oxytocin-RAGE interactions · plain
      “Endogenous oxytocin in human serum (30 pmol/50 ml) also co-eluted with soluble RAGE following isolation by anti-RAGE antibody affinity chromatography (Supplementary Figure 1b).”
    Quote in the paperSubstantial claim
  • Findingown data

    RAGE is expressed in CD31-positive endothelial cells of the hippocampus and choroid plexus in WT but not Ager−/− mice.

    “Immunohistochemical analyses showed RAGE in vascular patterns limited to CD31 (platelet endothelial cell adhesion molecule)-positive endothelial cells23, which are the components of the BBB, of the hippocampus and choroid plexus of WT (Fig. 3a, b) but not of Ager−/− mice (Supplementary Figure 4a).”
    • Also stated in: § Oxytocin transport across the BBB · plain
      “We also performed confocal microscopic analyses to observe RAGE expression in the circumventricular organs (CVOs) of the brain, referred to as ‘windows of the brain’, and found that RAGE expression was clearly observable in the endothelial cells of the neurohypophysis (Supplementary Figure 4b), but barely in those of the sensory CVOs, including the organum vasculosum of the lamina terminalis, subf”
    Quote in the paperSubstantial claim
  • Findingown data

    Endogenous oxytocin in human serum is structurally indistinguishable from a synthetic oxytocin standard by LC-MS/MS.

    “Analyses of the eluted fractions by liquid chromatography-tandem mass spectrometry (LC-MS/MS) showed that endogenous oxytocin in human serum is structurally indistinguishable from the synthetic oxytocin standard, as they eluted at identical times (Supplementary Figure 1d) and have identical parent ions (M+H+ 1008.2).”
    Quote in the paperNot a substantial claim
  • Findingown data

    RAGE co-localizes with caveolin-1 in endothelial cells and choroid plexus in WT mice.

    “Further analysis revealed co-localisation of RAGE with cavelolin-1, a marker of plasma membrane invaginations (caveolae), in endothelial cells and the choroid plexus in WT mice (Supplementary Figure 4c), suggesting a role of RAGE in the oxytocin transfer (trafficking) through caveolae-associated endocytosis and transcytosis (Supplementary Figure 4d).”
    Quote in the paperSubstantial claim
  • May combine two claims. 18
  • Classified as probably not a substantial claim. 19

  • May combine two claims.

    Findingown data

    Oxytocin does not stimulate or inhibit RAGE-dependent NF-κB signaling and does not activate Rac1 or Cdc42 signaling.

    “oxytocin neither stimulates a RAGE-dependent NF-κB reporter nor inhibits reporter induction by AGEs, a ligand that activates the NF-κB reporter22,27 (Supplementary Figure 2a).”
    • Also stated in: § Oxytocin-RAGE interactions · plain
      “Furthermore, oxytocin did not activate NF-κB-independent Rac1 or Cdc42 signalling, which are also suggested to function downstream of RAGE24,41,42 (Supplementary Figures 2b and 2c).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    In an in vitro BBB model, oxytocin transport is dose-dependent and is reduced selectively in the blood-to-brain direction following RAGE knockdown.

    “Endothelial transport of oxytocin was dose-dependent (Fig. 2b) and of a similar rate to transport of centrally acting drugs46.”
    • Also stated in: § Oxytocin transport across the BBB · plain
      “Notably, oxytocin transport was reduced selectively in the blood-to-brain direction following RAGE knockdown (Fig. 2b).”
    • Also stated in: § Oxytocin transport across the BBB · plain
      “Reverse transport was much less efficient (Fig. 2e), and according to calculated apparent permeability (Papp) measures, inconsequential (Fig. 2f).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Following subcutaneous oxytocin, CSF oxytocin increases in WT but not Ager−/− male mice.

    “By contrast, levels of oxytocin in CSF from the cisterna magna of WT mice increased more gradually to maxima at 1–2 h before returning to baseline at 4 h (Fig. 4a).”
    • Also stated in: § RAGE-dependent transport of oxytocin across the BBB · plain
      “Despite equivalently high serum levels following injection of identical amounts of oxytocin (Supplementary Figure 5a), concentrations in the CSF of Ager−/− mice remained at baseline levels (Fig. 4a).”
    • Also stated in: § RAGE-dependent transport of oxytocin across the BBB · plain
      “Following subcutaneous injection, oxytocin increased in third ventricle CSF of WT but not Ager−/− male mice (Fig. 4b and Supplementary Figure 5b).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    [13C,15N]oxytocin is undetectable in CSF of Ager−/− male mice but equivalent in WT and KO+Tg mice after subcutaneous injection.

    “Following subcutaneous injection, [13C,15N]oxytocin was undetectable in CSF of Ager−/− male mice, whereas amounts in the CSF of WT or KO + Tg mice were equivalent (Fig. 4f and Supplementary Figure 5e).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Transgenic endothelial RAGE expression in Ager−/− mice restores CSF oxytocin to WT levels, while in WT mice it minimally affects CSF oxytocin.

    “Tg expression in Ager−/− mice increased oxytocin in CSF to the WT concentration, whereas Tg expression in WT mice minimally affected CSF oxytocin concentrations (Fig. 4e and Supplementary Figure 5d).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Ager−/− male mice show hyperactivity that is normalized by intraventricular but not subcutaneous or nasal oxytocin.

    “During light-dark transition tests, the greater distances travelled (c) and greater average speed (d) in the light zone exhibited by Ager−/− male mice were both reduced by intraventricular (V) but not subcutaneous (sc) injection of oxytocin (OT) (n = 14–16).”
    • Also stated in: § Social behaviour in RAGE knockout mice · plain
      “Concordantly, intraventricular but not nasal administration of oxytocin normalised distances travelled by Ager−/− mice in open field tests (Fig. 7e).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Subcutaneous oxytocin increases c-Fos positive nuclei in BNST, mPOA, AHC, and ILS of WT but not Ager−/− male mice.

    “Numbers of c-Fos positive nuclei increased after subcutaneous oxytocin administration in four distinct regions of the brain, the bed nucleus of the stria terminalis (BNST), medial preoptic area (mPOA), centre of the anterior hypothalamic area (AHC) and ventral portion of the intermediate lateral septal nucleus (ILS) (Fig. 6a, b).”
    • Also stated in: § c-Fos as CNS actions of oxytocin · plain
      “This is dependent on both oxytocin and RAGE, as there are no effects in Ager−/− male mice or when vehicle control was administered (Fig. 6b).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Ager−/− pups have low survival due to maternal neglect; cross-fostering to WT mothers rescues survival, while WT pups with Ager−/− mothers do poorly.

    “Survival of Ager gene null (Ager−/−) pups is often low due to maternal neglect, with even mild maternal stress leading to dramatic reductions in offspring survival (Fig. 1a).”
    • Also stated in: § Oxytocin-RAGE interactions · boosted
      “This is clearly a maternal deficit, as newborn Ager−/− pups transferred to wild-type (WT) post-partum mothers are nurtured and survive at near normal frequencies. By contrast, normal offspring of WT mothers do poorly when transferred to post-partum Ager−/− mothers (Fig. 1b).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Mass spectrometry did not identify arginine-vasopressin in eluted material from immobilised esRAGE, and RAGE did not transport it in an in vitro BBB assay.

    “Mass spectrometry of the eluted material from the immobilised esRAGE in human serum did not identify arginine-vasopressin; additionally, RAGE did not transport it in an in vitro blood–brain barrier (BBB) assay system (Supplementary Figure 7).”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Oxytocin mediates physiological and psychosocial events surrounding mammalian birth, including uterine contractions, lactation, and maternal bonding.

    “Oxytocin mediates both physiological and psychosocial events surrounding mammalian birth, including uterine contractions, initiation of lactation, and maternal bonding1,2.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [1] Brunton, P. J. & Russell, J. A. The expectant brain: adapting for motherhood. Nat. Rev. Neurosci. 9, 11–25 (2008). source

      Not checked in the free run.

    • cites [2] Dulac, C., O’Connell, L. A. & Wu, Z. Neural control of maternal and paternal behaviors. Science 345, 765–770 (2014). source

      Not checked in the free run.

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

    Premisecitation

    Exogenous oxytocin has behavioural effects in humans, particularly in social deficit-related psychiatric disorders such as autism and schizophrenia.

    “Exogenous oxytocin in humans also appears to have behavioural effects, particularly in such social deficit-related psychiatric disorders as autism and schizophrenia9–13.”
    Quote in the paperNot a substantial claim0 of 5 sources checked
    • cites [9] Higashida, H., Yokoyama, S., Kikuchi, M. & Munesue, T. CD38 and its role in oxytocin secretion and social behavior. Horm. Behav. 61, 351–358 (2012). source

      Not checked in the free run.

    • cites [10] Insel, T. R. Translating oxytocin neuroscience to the clinic: A National Institute of Mental Health Perspective. Biol. Psychiatry 79, 153–154 (2016). source

      Not checked in the free run.

    • cites [11] Guastella, A. J. et al. Intranasal oxytocin improves emotion recognition for youth with autism spectrum disorders. Biol. Psychiatry 67, 692–694 (2010). source

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    • cites [12] Gordon, I. et al. Intranasal oxytocin enhances connectivity in the neural circuitry supporting social motivation and social perception in children with autism. Sci. Rep. 6, 35054 (2016). source

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    • cites [13] Feifel, D., Shilling, P. D. & MacDonald, K. A review of oxytocin’s effects on the positive, negative, and cognitive domains of schizophrenia. Biol. Psychiatry 79, 222–233 (2016). source

      Not checked in the free run.

  • May combine two claims.

    Premisereasoning

    Peripheral oxytocin replacement restores normal maternal behaviour in Oxt−/− and Cd38−/− mice but not Oxtr−/− mice, implying that circulating oxytocin crosses the blood-brain barrier.

    “Normal maternal behaviour is restored by peripheral oxcytocin replacement in Oxt−/− and Cd38−/−, but not Oxtr−/− mice, implying that circulating oxcytocin crosses the blood-brain barrier.”
    • Also stated in: § Introduction · hedged
      “This is restored by administration of exogenous oxytocin in Oxt−/− but not Oxtr−/− mice, suggesting that peripheral oxytocin has central effects.”
    • Also stated in: § Introduction · plain
      “Mice lacking CD38, a cyclic ADP ribose synthetase and hydrolase necessary for secretion of oxytocin, also display this characteristic behavioural phenotype, which is also reversed following administration of exogenous oxytocin5,9.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [5] Jin, D. et al. CD38 is critical for social behaviour by regulating oxytocin secretion. Nature 446, 41–45 (2007). source

      Not checked in the free run.

    • cites [9] Higashida, H., Yokoyama, S., Kikuchi, M. & Munesue, T. CD38 and its role in oxytocin secretion and social behavior. Horm. Behav. 61, 351–358 (2012). source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    RAGE is not known to be related to oxytocin or oxytocin signalling.

    “RAGE, a member of the immunoglobulin superfamily of pattern recognition receptors, is not known to be related to oxytocin or oxytocin signalling22–33.”
    Quote in the paperSubstantial claim0 of 10 sources checked
    • cites [22] Senatus, L. M. & Schmidt, A. M. The AGE-RAGE axis: implications for age-associated arterial diseases. Front. Genet. 8, 187 (2017). source

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    • cites [23] Kamide, T. et al. RAGE mediates vascular injury and inflammation after global cerebral ischemia. Neurochem. Int. 60, 220–228 (2012). source

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    • cites [24] Manigrasso, M. B., Juranek, J., Ramasamy, R. & Schmidt, A. M. Unlocking the biology of RAGE in diabetic microvascular complications. Trends Endocrinol. Metab. 25, 15–22 (2014). source

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    • cites [25] Takuma, K. et al. RAGE-mediated signaling contributes to intraneuronal transport of amyloid-beta and neuronal dysfunction. Proc. Natl Acad. Sci. USA 106, 20021–20026 (2009). source

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    • cites [26] Yamamoto, Y. et al. Development and prevention of advanced diabetic nephropathy in RAGE-overexpressing mice. J. Clin. Invest. 108, 261–268 (2001). source

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    • cites [27] Yamamoto, Y. et al. Septic shock is associated with receptor for advanced glycation end products ligation of LPS. J. Immunol. 186, 3248–3257 (2011). source

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    • cites [28] Yamamoto, Y. & Yamamoto, H. RAGE-mediated inflammation, type 2 diabetes, and diabetic vascular complication. Front. Endocrinol. 4, 105 (2013). source

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    • cites [29] Yonekura, H. et al. Novel splice variants of the receptor for advanced glycation end-products expressed in human vascular endothelial cells and pericytes, and their putative roles in diabetes-induced vascular injury. Biochem. J. 370, 1097–1109 (2003). source

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    • cites [31] Mackic, J. B. et al. Human blood-brain barrier receptors for Alzheimer’s amyloid-beta 1- 40. Asymmetrical binding, endocytosis, and transcytosis at the apical side of brain microvascular endothelial cell monolayer. J. Clin. Invest. 102, 734–743 (1998). source

      Not checked in the free run.

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

    Premisecitation

    The three RAGE forms bind various ligands with similar affinities, including AGEs and amyloid β peptide.

    “The three RAGE forms bind various ligands with similar affinities, including multiple advanced glycation end-products (AGEs) and amyloid β peptide31–37.”
    Quote in the paperNot a substantial claim0 of 7 sources checked
    • cites [31] Mackic, J. B. et al. Human blood-brain barrier receptors for Alzheimer’s amyloid-beta 1- 40. Asymmetrical binding, endocytosis, and transcytosis at the apical side of brain microvascular endothelial cell monolayer. J. Clin. Invest. 102, 734–743 (1998). source

      Not checked in the free run.

    • cites [32] Yamamoto, Y. et al. Short-chain aldehyde-derived ligands for RAGE and their actions on endothelial cells. Diabetes Res. Clin. Pract. 77, S30–S40 (2007). source

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    • cites [33] Matsumoto, K. et al. Immunohistochemical analysis of transporters related to clearance of amyloid-β peptides through blood-cerebrospinal fluid barrier in human brain. Histochem. Cell. Biol. 144, 597–611 (2015). source

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    • cites [34] Deane, R. et al. RAGE mediates amyloid-beta peptide transport across the blood-brain barrier and accumulation in brain. Nat. Med. 9, 907–913 (2003). source

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    • cites [35] Deane, R. et al. A multimodal RAGE-specific inhibitor reduces amyloid β-mediated brain disorder in a mouse model of Alzheimer disease. J. Clin. Invest. 122, 1377–1392 (2012). source

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    • cites [36] Saito, R., Araki, S., Yamamoto, Y. & Kusuhara, K. Elevated endogenous secretory receptor for advanced glycation end products (esRAGE) levels are associated with circulating soluble RAGE levels in diabetic children. J. Pediatr. Endocrinol. Metab. 30, 63–69 (2017). source

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    • cites [37] Gasparotto, J. et al. Receptor for advanced glycation end products mediates sepsis-triggered amyloid-β accumulation, Tau phosphorylation, and cognitive impairment. J. Biol. Chem. 293, 226–244 (2018). source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data

    Bilateral common carotid artery occlusion does not cause fluorescein to leak into the CSF, suggesting no generalised increase in vascular permeability.

    “As a control, we showed this procedure does not cause fluorescein to leak into the CSF (Fig. 5c), suggesting there is not a generalised increase in vascular permeability.”
    Quote in the paperSubstantial claim

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

    Premisecitation

    c-Fos positive neurons are activated during the acquisition of postpartum maternal behaviours.

    “The classical studies of Numan showed c-Fos positive neurons are activated during the acquisition of postpartum maternal behaviours51.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [51] Numan, M. & Numan, M. J. Projection sites of medial preoptic area and ventral bed nucleus of the stria terminalis neurons that express Fos during maternal behavior in female rats. J. Neuroendocrinol. 9, 369–384 (1997). source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    RAGE is both necessary and sufficient for oxytocin transport into the brain in both male and female mice.

    “These results demonstrated that RAGE is both necessary and sufficient for oxytocin transport into the brain in both male and female mice.”
    Quote in the paperSubstantial claim

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

    Premisecitation

    RAGE is being targeted for inhibition in drug discovery efforts.

    “Since both of these are deleterious, pathological effects, RAGE is being targeted for inhibition in drug discovery efforts35.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [35] Deane, R. et al. A multimodal RAGE-specific inhibitor reduces amyloid β-mediated brain disorder in a mouse model of Alzheimer disease. J. Clin. Invest. 122, 1377–1392 (2012). source

      Not checked in the free run.

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

    Premisecitation

    RAGE has been shown to transport amyloid β peptide across the blood-brain barrier, promoting Alzheimer disease-like symptoms in susceptible mice.

    “For example, RAGE has been shown to transport amyloid β peptide across the BBB, which promotes Alzheimer disease-like symptoms in susceptible mice.”
    Quote in the paperNot a substantial claim

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

    Premisecitation

    The affinity of oxytocin binding to the oxytocin receptor has often been estimated to be KD ~100 nM, although a high affinity form with KD ~1 nM has also been reported.

    “The affinity of oxytocin binding to the oxytocin receptor has often been estimated to be KD ~100 nM, although a high affinity form with KD ~1 nM has also been reported60.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [60] Gimpl, G. & Fahrenholz, F. The oxytocin receptor system: structure, function, and regulation. Physiol. Rev. 81, 629–683 (2001). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Loss of maternal nurturing and social interactive behaviours in Cd38−/− mice are restored following peripheral oxytocin, consistent with transport of peripherally administered oxytocin into the brain.

    “Loss of maternal nurturing and social interactive behaviours in Cd38−/− mice have been restored following peripheral administration of oxytocin, consistent with transport of peripherally administered exogenous oxytocin into brain5.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [5] Jin, D. et al. CD38 is critical for social behaviour by regulating oxytocin secretion. Nature 446, 41–45 (2007). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Levels of oxytocin in the periphery are lower than those in the CSF in humans, providing a concentration gradient for transport.

    “Levels of oxytocin in the periphery are lower than those in the CSF, in humans16,61,62, providing a concentration gradient for what appears to be a transport mechanism: this point of view depends on the methods of oxytocin measurements in blood, because a recent report has shown much higher blood OT levels than previously thought using a robust nanoLC-MS platform63.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [16] Striepens, N. et al. Elevated cerebrospinal fluid and blood concentrations of oxytocin following its intranasal administration in humans. Sci. Rep. 3, 3440 (2013). source

      Not checked in the free run.

    • cites [61] Kagerbauer, S. M. et al. Plasma oxytocin and vasopressin do not predict neuropeptide concentrations in human cerebrospinal fluid. J. Neuroendocrinol. 25, 668–673 (2013). source

      Not checked in the free run.

    • cites [62] Martin, J. et al. Vasopressin and oxytocin in CSF and plasma of patients with aneurysmal subarachnoid haemorrhage. Neuropeptides 48, 91–96 (2014). source

      Not checked in the free run.

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

    Premisecitation

    Clinical studies have linked autism and Asperger's disorders and attention-deficit/hyperactivity disorders to oxytocin deficiency.

    “Clinical studies have linked autism and Asperger’s disorders and attention-deficit/hyperactivity disorders to oxytocin deficiency7,8,54, and the potential use of exogenous oxytocin to treat these conditions is being assessed in clinical trials10,11,54–57.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [7] Insel, T. R. The challenge of translation in social neuroscience: a review of oxytocin, vasopressin, and affiliative behavior. Neuron 65, 768–779 (2010). source

      Not checked in the free run.

    • cites [8] Rilling, J. K. & Young, L. J. The biology of mammalian parenting and its effect on offspring social development. Science 345, 771–776 (2014). source

      Not checked in the free run.

    • cites [54] Feldman, R. et al. Sensitive parenting is associated with plasma oxytocin and polymorphisms in the OXTR and CD38 genes. Biol. Psychiatry 72, 175–181 (2012). source

      Not checked in the free run.

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

    Premisenone given

    RAGE is implicated in the pathogenesis of diabetes complications.

    “RAGE has also been implicated in the pathogenesis of diabetes complications.”
    Quote in the paperNot a substantial claim

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

    Study design and conductnone given

    The oxytocin assay had two linear ranges: a lower concentration range from a few to 30 pg/ml, and a higher concentration range between 50 and 1000 pg/ml.

    “The oxytocin assay had two linear ranges, which covers a lower concentration range from a few to 30 pg/ml, and a higher concentration range between 50 and 1000 pg/ml.”
    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

    All animal experiments were approved by the Committee on Animal Experimentation of Kanazawa University and performed in accordance with the Fundamental Guidelines for Proper Conduct of Animal Experiment and Related Activities in Academic Research Institutions under the jurisdiction of the Ministry of Education, Culture, Sports, Science and Technology of Japan.

    “All animal experiments were approved by the Committee on Animal Experimentation of Kanazawa University and performed in accordance with the Fundamental Guidelines for Proper Conduct of Animal Experiment and Related Activities in Academic Research Institutions under the jurisdiction of the Ministry of Education, Culture, Sports, Science and Technology of Japan.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductcitation

    CSF was collected according to the protocol for sampling CSF from mice without detectable plasma contamination.

    “CSF was collected according to the protocol for sampling CSF from mice without detectable plasma contamination77,78.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [77] Lopatina, O. et al. H. Communication impairment in ultrasonic vocal repertoire during the suckling period of Cd157 knockout mice: transient improvement by oxytocin. Front. Neurosci. 11, 266 (2017). source

      Not checked in the free run.

    • cites [78] Liu, L. & Duff, K. A technique for serial collection of cerebrospinal fluid from the cisterna magna in mouse. J. Vis. Exp. 21, pii: 960 (2008).

      Not checked in the free run.

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

    Study design and conductnone given

    An additional extraction step may have resulted in lower than actual oxytocin levels.

    “whereas an additional extraction step may have resulted in lower than actual oxytocin levels.”
    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

    The inter-assay and intra-assay coefficients of variation of the oxytocin assay were less than 15%.

    “The inter-assay and intra-assay coefficients of variation were less than 15%.”
    Quote in the paperNot a substantial claim

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

    Study design and conductnone given

    In the cerebral ischaemia model, mice that exhibited <15% of the baseline control microperfusion during the first minute of occlusion were used in subsequent experiments.

    “In our experimental model, the mice that exhibited <15% of the baseline control microperfusion during the first minute of occlusion were used in subsequent experiments.”
    Quote in the paperNot a substantial claim

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

    Study design and conductcitation

    The in vitro BBB models were established within 4 days of seeding the cells according to the manufacturer's instructions.

    “The in vitro BBB models were established within 4 days of seeding the cells according to the manufacturer’s instructions46.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [46] Nakagawa, S. et al. Pericytes from brain microvessels strengthen the barrier integrity in primary cultures of rat brain endothelial cells. Cell. Mol. Neurobiol. 27, 687–694 (2007). source

      Not checked in the free run.

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

    Study design and conductnone given

    Unextracted samples result in binding of complexes of oxytocin stuck to interacting proteins.

    “though unextracted samples result in binding of complexes of oxytocin stuck to interacting proteins.”
    Quote in the paperNot a substantial claim

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

    Premisecitation

    The open field test is meant to assess anxious behaviour.

    “The open field test is meant to assess anxious behaviour80.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [80] Zhong., J. et al. Cyclic ADP-ribose and heat regulate oxytocin release via CD38 and TRPM2 in the hypothalamus during social or psychological stress in mice. Front. Neurosci. 10, 304 (2016). source

      Not checked in the free run.

    • Rests on an assumption: Mice naturally prefer to be near protective walls rather than being exposed to potential dangers in open spaces.
33 of 33

  • The paper relies on this without support.

    Mice naturally prefer to be near protective walls rather than being exposed to potential dangers in open spaces.

    “This test is based on the idea that mice naturally prefer to be near protective walls rather than being exposed to potential dangers in open spaces.”

  • The paper relies on this without support.

    Sodium fluorescein (MW 376.3) does not cross an intact blood-brain barrier.

    “Sodium fluorescein (MW 376.3) is a fluorescent tracer that does not cross an intact BBB.”

  • The paper relies on this without support.

    Trans-endothelial electrical resistance (TEER) primarily reflects the flux of sodium ions through the cell layers in the culture conditions.

    “Trans-endothelial electrical resistance (TEER), which primarily reflects the flux of sodium ions through the cell layers in the culture conditions, was measured with an epithelial-volt-ohm metre and an Endohm-6 chamber electrodes (World Precision Instruments, Sarasota, FL, USA).”
3 of 3

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

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.

  • Intranasal oxytocin concentration differs between figure and methods

    Major

    The Fig. 7e caption specifies 100 ng/ml for nasal administration, whereas the administration method specifies 1000 ng/ml for the same 20 μl volume.

1 of 1

Cites

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1 of the 84 references couldn’t be matched to a known paper.

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Authors
Yamamoto, Y., Liang, M., Munesue, S., Deguchi, K., Harashima, A., Furuhara, K., Yuhi, T., Zhong, J., Akther, S., Goto, H., Eguchi, Y., Kitao, Y., Hori, O., Shiraishi, Y., Ozaki, N., Shimizu, Y., Kamide, T., Yoshikawa, A., Hayashi, Y., Nakada, M., Lopatina, O., Gerasimenko, M., Komleva, Y., Malinovskaya, N., Salmina, A. B., Asano, M., Nishimori, K., Shoelson, S. E., Yamamoto, H., & Higashida, H.
Affiliations
  • Kanazawa University (JP)
  • Kanazawa Medical University (JP)
  • Krasnoyarsk State Medical University (RU)
  • Tohoku University (JP)
  • Joslin Diabetes Center (US)
Corresponding author
  • Yamamoto, Yasuhiko
  • Higashida, Haruhiro
ORCID
Venue
Communications Biology
Publisher
Springer Science and Business Media LLC
Published
2019-02-25
Volume
2
Issue
1
Pages
76-76
ISSN
2399-3642 (ISSN-L)
DOI
10.1038/s42003-019-0325-6
PMC
PMC6389896
OpenAlex
W2915217457
Semantic Scholar
15105180d45078885146968dd9ad52c15161b461
Cited by
171
References
84
Citations by year
2026: 14 · 2025: 9 · 2024: 13 · 2023: 17 · 2022: 23 · 2021: 40 · 2020: 44 · 2019: 11
FWCI
37.36
Type
journal article
Language
en
Open access
Licence
Locations
  • Communications Biology (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, other-oa)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
Funders
  • Kanazawa University
  • Ministry of Education, Culture, Sports, Science and Technology
  • Japan Society for the Promotion of Science (17K09031, 18K06889, 25461335, 18KK0255, 24590375, 18K06500, 18K07551)
  • National Institute of Diabetes and Digestive and Kidney Diseases (P30DK036836)
Topics
  • Social Sciences › Psychology › Social Psychology › Neuroendocrine regulation and behavior
  • Life Sciences › Neuroscience › Neurology › Barrier Structure and Function Studies
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neuropeptides and Animal Physiology
Keywords
oxytocin, receptor for advanced glycation end products, RAGE, blood-brain barrier, brain microvascular endothelial cells, maternal behavior, social bonding, hyperactivity, oxytocin receptor
MeSH terms
Receptor for Advanced Glycation End Products, Animals, Brain, Female, Humans, Male, Maternal Behavior, Mice, Inbred C57BL, Mice, Transgenic, Object Attachment, Oxytocin, Receptors, Oxytocin, Mice, Knockout, Endothelial Cells

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 2026-10-09.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-09.

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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