title: Adolescent voluntary exercise attenuated hippocampal innate immunity responses and depressive-like behaviors following maternal separation stress in male rats.
abstract: Early life stressful events have detrimental effects on the brain and behavior, which are associated with the development of depression. Immune-inflammatory responses have been reported to contribute in the pathophysiology of depression. Many studies have reported on the beneficial effects of exercise against stress. However, underlying mechanisms through which exercise exerts its effects were poorly studied. Therefore, it applied maternal separation (MS), as a valid animal model of early-life adversity, in rats from postnatal day (PND) 2 to 14 for 180min per day. At PND 28, male Wistar albino rats were subjected to 5 experimental groups; 1) controls 2) MS rats 3) MS rats treated with fluoxetine 5mg/kg to PND 60, 4) MS rats that were subjected to voluntary running wheel (RW) exercise and 5) MS rats that were subjected to mandatory treadmill (TM) exercise until adulthood. At PND 60, depressive-like behaviors were assessed by using forced swimming test (FST), splash test, and sucrose preference test (SPT). Our results revealed that depressive-like behaviors following MS stress were associated with an increase in expression of toll-like receptor 4 (Tlr-4) and its main signaling protein, Myd88, in the hippocampal formation. Also, we found that voluntary (and not mandatory) physical exercise during adolescence is protected against depressant effects of early-life stress at least partly through mitigating the innate immune responses in the hippocampus.
authors.affiliation: Department of Exercise Physiology, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Sadeghi
authors.affiliation: Department of Exercise Physiology, Central Tehran Branch, Islamic Azad University, Tehran, Iran. Electronic address: mpeeri@iauctb.ac.ir.
authors.forename: Maghsoud
authors.initials: M
authors.lastname: Peeri
authors.affiliation: Department of Pharmacology and Toxicology, Faculty of Pharmacy, Zanjan University of Medical Sciences, Zanjan, Iran; Zanjan Applied Pharmacology Research Center, Zanjan University of Medical sciences, Zanjan, Iran.
authors.forename: Mir-Jamal
authors.initials: MJ
authors.lastname: Hosseini
mesh_terms: D000367:Age Factors; D000818:Animals; D018687:Antidepressive Agents, Second-Generation / Q000494:pharmacology / Q000627:therapeutic use; D003863:Depression / Q000209:etiology* / Q000473:pathology / Q000534:rehabilitation; D004195:Disease Models, Animal; D005080:Exercise Test; D005106:Exploratory Behavior / Q000187:drug effects; D005260:Female; D005473:Fluoxetine / Q000627:therapeutic use; D005518:Food Preferences / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D006624:Hippocampus; D007113:Immunity, Innate / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008426:Maternal Deprivation; D009042:Motivation / Q000187:drug effects; D010805:Physical Conditioning, Animal / Q000502:physiology; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D051197:Toll-Like Receptor 4 / Q000235:genetics / Q000378:metabolism
chemical_list: D018687:Antidepressive Agents, Second-Generation; D051197:Toll-Like Receptor 4; D005473:Fluoxetine
keywords: Depressive-like behaviors; Hippocampus; Mandatory exercise; Maternal separation; Toll-like receptors; Voluntary exercise