{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T11:09:27Z","timestamp":1781176167516,"version":"3.54.1"},"reference-count":37,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,30]],"date-time":"2025-12-30T00:00:00Z","timestamp":1767052800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Russian Foundation for Basic Research","award":["20-015-00470"],"award-info":[{"award-number":["20-015-00470"]}]},{"DOI":"10.13039\/100019130","name":"IKBFU","doi-asserted-by":"crossref","award":["123110800174-4"],"award-info":[{"award-number":["123110800174-4"]}],"id":[{"id":"10.13039\/100019130","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Russian Ministry of Science and Education"},{"name":"Charit\u00e9 University Medicine Berlin"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Growing evidence suggests that psychiatric disorders are characterized by a prolonged inflammatory state, which may influence the efficacy of compounds targeting serotonin. Serotonin is a key signaling molecule in neuroplasticity of the adult hippocampus and involved in antidepressant action. Recent in vitro studies indicate the neurotransmitter may also facilitate the response to inflammation and potentially modulate microglial function towards neuroprotection. Using Tph2\u2212\/\u2212 rats depleted of brain serotonin, we examined microglial expression of various serotonin receptors (5-HTRs) in vivo in both the hippocampus and prefrontal cortex and assessed mRNA levels of cytokines and brain-derived neurotrophic factor (BDNF). We observed age-dependent and region-specific gene expression of 5-HTRs on sorted microglia, paralleling changes in BDNF signaling, especially with 5-HT2b. Notably, both 5-HT2b and BDNF expression in the hippocampus was significantly upregulated in the absence of brain serotonin. Our data indicate distinct roles of 5-HTR subtypes in early network formation (5-HT1b, 5-HT5b) and in the response to endogenous changes (5-HT2b, 5-HT5a). Understanding serotonin\u2013microglia interplay could offer therapeutic insights into the maintenance of mood via brain\u2013immune cell interactions.<\/jats:p>","DOI":"10.3390\/cells15010066","type":"journal-article","created":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T16:34:23Z","timestamp":1767198863000},"page":"66","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Microglial Expression of Serotonin Receptors Reveals Parallel Regulation of 5-HT2b and BDNF in the Rat Hippocampus"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0175-3293","authenticated-orcid":false,"given":"Andrei","family":"Turkin","sequence":"first","affiliation":[{"name":"Institute of Medicine and Life Sciences (MEDBIO), Immanuel Kant Baltic Federal University, Kaliningrad 236035, Russia"},{"name":"Max Delbr\u00fcck Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Sidorova","sequence":"additional","affiliation":[{"name":"Institute of Medicine and Life Sciences (MEDBIO), Immanuel Kant Baltic Federal University, Kaliningrad 236035, Russia"},{"name":"Max Delbr\u00fcck Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ekaterina","family":"Kurilova","sequence":"additional","affiliation":[{"name":"Institute of Medicine and Life Sciences (MEDBIO), Immanuel Kant Baltic Federal University, Kaliningrad 236035, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6071-5433","authenticated-orcid":false,"given":"Natalia","family":"Alenina","sequence":"additional","affiliation":[{"name":"Max Delbr\u00fcck Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1480-1311","authenticated-orcid":false,"given":"Oksana","family":"Tuchina","sequence":"additional","affiliation":[{"name":"Institute of Medicine and Life Sciences (MEDBIO), Immanuel Kant Baltic Federal University, Kaliningrad 236035, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3171-0497","authenticated-orcid":false,"given":"Friederike","family":"Klempin","sequence":"additional","affiliation":[{"name":"Max Delbr\u00fcck Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany"},{"name":"Department of Psychiatry and Psychotherapy, Charit\u00e9 University Medicine Berlin, 10117 Berlin, Germany"},{"name":"LSU Health Sciences Center, Department of Neurology, New Orleans, LA 70112, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"483","DOI":"10.1016\/j.stem.2010.08.014","article-title":"Microglia shape adult hippocampal neurogenesis through apoptosis-coupled phagocytosis","volume":"7","author":"Sierra","year":"2010","journal-title":"Cell Stem Cell"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Miller, V.K., and Broadie, K. 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