title: Social Isolation Stress Induces Anxious-Depressive-Like Behavior and Alterations of Neuroplasticity-Related Genes in Adult Male Mice.
abstract: Stress is a major risk factor in the onset of several neuropsychiatric disorders including anxiety and depression. Although several studies have shown that social isolation stress during postweaning period induces behavioral and brain molecular changes, the effects of social isolation on behavior during adulthood have been less characterized. Aim of this work was to investigate the relationship between the behavioral alterations and brain molecular changes induced by chronic social isolation stress in adult male mice. Plasma corticosterone levels and adrenal glands weight were also analyzed. Socially isolated (SI) mice showed higher locomotor activity, spent less time in the open field center, and displayed higher immobility time in the tail suspension test compared to group-housed (GH) mice. SI mice exhibited reduced plasma corticosterone levels and reduced difference between right and left adrenal glands. SI showed lower mRNA levels of the BDNF-7 splice variant, c-Fos, Arc, and Egr-1 in both hippocampus and prefrontal cortex compared to GH mice. Finally, SI mice exhibited selectively reduced mGluR1 and mGluR2 levels in the prefrontal cortex. Altogether, these results suggest that anxious- and depressive-like behavior induced by social isolation stress correlates with reduction of several neuroplasticity-related genes in the hippocampus and prefrontal cortex of adult male mice.
authors.affiliation: Laboratorio di Neuropsicofarmacologia e Neurogenomica Funzionale, Dipartimento di Scienze Farmacologiche e Biomolecolari e Centro di Eccellenza sulle Malattie Neurodegenerative, Università di Milano, Milano, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Ieraci
authors.affiliation: Laboratorio di Neuropsicofarmacologia e Neurogenomica Funzionale, Dipartimento di Scienze Farmacologiche e Biomolecolari e Centro di Eccellenza sulle Malattie Neurodegenerative, Università di Milano, Milano, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Mallei
authors.affiliation: Laboratorio di Neuropsicofarmacologia e Neurogenomica Funzionale, Dipartimento di Scienze Farmacologiche e Biomolecolari e Centro di Eccellenza sulle Malattie Neurodegenerative, Università di Milano, Milano, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Popoli
mesh_terms: D000311:Adrenal Glands / Q000473:pathology; D000818:Animals; D001007:Anxiety / Q000209:etiology / Q000235:genetics*; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism; D003345:Corticosterone / Q000097:blood; D003598:Cytoskeletal Proteins / Q000378:metabolism; D003863:Depression / Q000209:etiology / Q000235:genetics*; D051766:Early Growth Response Protein 1 / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009473:Neuronal Plasticity / Q000235:genetics*; D009929:Organ Size; D017397:Prefrontal Cortex / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D012934:Social Isolation; D013315:Stress, Psychological / Q000097:blood / Q000150:complications* / Q000235:genetics*
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D003598:Cytoskeletal Proteins; D051766:Early Growth Response Protein 1; C486109:Egr1 protein, mouse; D009419:Nerve Tissue Proteins; D016760:Proto-Oncogene Proteins c-fos; C092069:activity regulated cytoskeletal-associated protein; D003345:Corticosterone