Wheel running prevents the accumulation of monounsaturated fatty acids in the liver of ovariectomized mice by attenuating changes in SCD-1 content.
Decreases in female sex steroids enhance the accumulation of visceral fat mass, leading to a predisposition to developing metabolic diseases. The purpose of this study was to determine whether loss of ovarian function alters the amount and (or) the fatty acid (FA) composition of triacylglycerol (TAG) levels in the liver of ovary-intact (SHAM) or ovariectomized (OVX) mice. We also sought to determine whether voluntary wheel running could attenuate the associated changes in the liver. Twenty-two C57/BL6 female mice were divided into 2 groups (SHAM, OVX) and were then subdivided into sedentary and exercising groups (SHAM-Sed, SHAM-Ex, OVX-Sed, OVX-Ex). Visceral fat mass significantly increased in the OVX-Sed animals; however, the effect was attenuated in the OVX-Ex animals. Total hepatic TAG content did not significantly increase in the OVX-Sed animals; however, SHAM-Ex and OVX-Ex animals demonstrated significant decreases in TAG levels. A significant increase in the FA desaturase index (18:1/18:0 and 16:1/16:0) was detected in the OVX-Sed animals compared with all other groups, which corresponded to increases in stearoyl-CoA desaturase (SCD-1) content. These results indicate that loss of ovarian function alters FA composition of hepatic TAG mediated by increases in SCD-1. These data indicate that female sex steroids influence lipid metabolism in the liver and provide important insight concerning the influence of exercise on hepatic function.
Department of Kinesiology, School of Public Health, University of Maryland, College Park, MD 21045, USA.
Kathryn C
KC
Jackson
Lindsay M
LM
Wohlers
Ana P
AP
Valencia
Michelle
M
Cilenti
Sarah J
SJ
Borengasser
John P
JP
Thyfault
Espen E
EE
Spangenburg
D050154:Adiposity; D000818:Animals; D001522:Behavior, Animal; D051048:Diacylglycerol O-Acyltransferase / Q000235:genetics / Q000378:metabolism; D004075:Diglycerides / Q000378:metabolism; D005229:Fatty Acids, Monounsaturated / Q000378:metabolism*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D006943:Hyperglycemia / Q000209:etiology; D050152:Intra-Abdominal Fat / Q000473:pathology; D008099:Liver / Q000378:metabolism*; D008593:Menopause / Q000097:blood / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D009043:Motor Activity; D010052:Ovariectomy / Q000009:adverse effects*; D050177:Overweight / Q000517:prevention & control; D012333:RNA, Messenger / Q000378:metabolism; D013230:Stearoyl-CoA Desaturase / Q000378:metabolism*; D014280:Triglycerides / Q000378:metabolism
D004075:Diglycerides; D005229:Fatty Acids, Monounsaturated; D012333:RNA, Messenger; D014280:Triglycerides; C490333:Scd1 protein, mouse; D013230:Stearoyl-CoA Desaturase; C494882:Dgat1 protein, mouse; D051048:Diacylglycerol O-Acyltransferase