Brain-derived neurotrophic factor serum levels in genetically isolated populations: gender-specific association with anxiety disorder subtypes but not with anxiety levels or Val66Met polymorphism
Open accessAbstract
Anxiety disorders (ADs) are disabling chronic disorders with exaggerated behavioral response to threats. This study was aimed at testing the hypothesis that ADs may be associated with reduced neurotrophic activity, particularly of Brain-derived neurotrophic factor (BDNF), and determining possible effects of genetics on serum BDNF concentrations. In 672 adult subjects from six isolated villages in North-Eastern Italy with high inbreeding, we determined serum BDNF levels and identified subjects with different ADs subtypes such as Social and Specific Phobias (PHSOC, PHSP), Generalized Anxiety Disorder (GAD), and Panic Disorder (PAD). Analysis of the population as a whole or individual village showed no significant correlation between serum BDNF levels and Val66Met polymorphism and no association with anxiety levels. Stratification of subjects highlighted a significant decrease in serum BDNF in females with GAD and males with PHSP. This study indicates low heritability and absence of any impact of the Val66Met polymorphism on circulating concentrations of BDNF. Our results show that BDNF is not a general biomarker of anxiety but serum BDNF levels correlate in a gender-specific manner with ADs subtypes.
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Several studies agree that BDNF serum levels fail to act as biomarkers for anxiety since dysregulated expression of this factor is present in multiple psychiatric illnesses including depression and schizophrenia.
“Several studies agree that BDNF serum levels fail to act as biomarkers for anxiety since dysregulated expression of this factor is present in multiple psychiatric illnesses including depression and schizophrenia (Molendijk et al., 2012; Carlino et al., 2015; Cattaneo et al., 2016).”
From The Epigenetics of Anxiety Pathophysiology: A DNA Methylation and Histone Modification Focused Review (2023) · cites this paper as Carlino et al., 2015
The Discussion (page unavailable) explicitly concludes that serum BDNF is not a general biomarker of anxiety, citing the lack of a significant difference between anxious subjects and healthy donors. The Introduction reports altered blood BDNF levels in depression, but the paper does not give dysregulation across depression and schizophrenia as the reason for its biomarker conclusion. (LLM, conf=0.88)
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- Authors
- Carlino, D., Francavilla, R., Baj, G., Kulak, K., d’Adamo, P., Ulivi, S., Cappellani, S., Gasparini, P., & Tongiorgi, E.
- Affiliations
- University of Trieste (IT)
- Department of Life Sciences, University of Trieste, Trieste, Italy
- IRCCS Materno Infantile Burlo Garofolo (IT)
- Corresponding author
- Tongiorgi, Enrico
- ORCID
- Venue
- PeerJ
- Publisher
- PeerJ
- Published
- 2015-10-29
- Volume
- 3
- Pages
- e1252
- ISSN
- 2167-8359 (ISSN-L)
- PMC
- PMC4631459
- OpenAlex
- W2141430911
- Cited by
- 23
- References
- 46
- Citations by year
- 2026: 2 · 2024: 1 · 2023: 5 · 2022: 2 · 2021: 3 · 2020: 5 · 2018: 2 · 2017: 2 · 2016: 1
- FWCI
- 2.52
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- PeerJ (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- ArTS Archivio della ricerca di Trieste (University of Trieste https://www.units.it/) (submittedVersion, other-oa)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Funders
- Sanofi Aventis
- Department of Life Sciences, University of Trieste
- Topics
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Anxiety, Depression, Psychometrics, Treatment, Cognitive Processes
- Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neurotransmitter Receptor Influence on Behavior
- Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Nerve injury and regeneration
- Keywords
- brain-derived neurotrophic factor, serum BDNF, anxiety disorders, BDNF Val66Met polymorphism, generalized anxiety disorder, social anxiety disorder, specific phobia, panic disorder, gender differences, inbred populations, genetic isolation, heritability
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