title: Effects of social isolation and environmental enrichment on atherosclerosis in ApoE-/- mice.
abstract: Social support and a stimulating environment have been suggested to reduce stress reactions and cardiovascular risk. The aim of this study was to assess the role of environmental enrichment and social interaction for development of atherosclerosis in atherosclerosis prone mice. Male ApoE-/- mice were divided into four groups and followed during 20 weeks: (i) enriched environment (E, n=12), (ii) deprived environment (ED, n=12), (iii) enriched environment with exercise (E-Ex, n=12) and (iv) socially deprived by individual housing (SD, n=10). Plasma lipid and cytokine concentrations were measured. Atherosclerosis was quantified in cross-sections of innominate artery and en face in thoracic aorta. Plaque area was significantly increased in SD mice in the innominate artery (P<0.05 vs. all other groups), but not in the thoracic aorta. Plasma lipids were increased in SD mice (P<0.001 vs. all for total cholesterol, P<0.05 vs. E and P<0.01 vs. ED for triglycerides). Plasma concentration of granulocyte-colony stimulating factor (G-CSF) was decreased in SD mice compared to E mice (P<0.05). Thus, social isolation increased atherosclerosis and plasma lipids in ApoE-/- mice. Reduction in plasma G-CSF levels may hamper endothelial regeneration in the atherosclerotic process. While environmental enrichment did not affect atherosclerosis, social isolation accelerated atherosclerosis.
authors.affiliation: Department of Molecular and Clinical Medicine/Clinical Physiology, Institute of Medicine, The Sahlgrenska Academy, Götenborg University, Göteborg, Sweden.
authors.forename: Evelina
authors.initials: E
authors.lastname: Bernberg
authors.forename: Irene J
authors.initials: IJ
authors.lastname: Andersson
authors.forename: Li-ming
authors.initials: LM
authors.lastname: Gan
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Naylor
authors.forename: Maria E
authors.initials: ME
authors.lastname: Johansson
authors.forename: Göran
authors.initials: G
authors.lastname: Bergström
mesh_terms: D000818:Animals; D001057:Apolipoproteins E / Q000172:deficiency*; D050197:Atherosclerosis / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D001794:Blood Pressure; D003345:Corticosterone / Q000652:urine; D004327:Drinking Behavior; D004777:Environment; D005106:Exploratory Behavior / Q000502:physiology; D016179:Granulocyte Colony-Stimulating Factor / Q000097:blood; D006339:Heart Rate; D006799:Housing, Animal; D008055:Lipids / Q000097:blood; D008297:Male; D051379:Mice; D010805:Physical Conditioning, Animal; D012934:Social Isolation; D012982:Sodium, Dietary / Q000008:administration & dosage
chemical_list: D001057:Apolipoproteins E; D008055:Lipids; D012982:Sodium, Dietary; D016179:Granulocyte Colony-Stimulating Factor; D003345:Corticosterone