Obesity is a medical condition in which excess body fat has accumulated to an extent and may have an adverse effect on health,leading to reduced life expec-tancy,impaired energy homeostasis and increased health proble...Obesity is a medical condition in which excess body fat has accumulated to an extent and may have an adverse effect on health,leading to reduced life expec-tancy,impaired energy homeostasis and increased health problems.The p160 steroid receptor coactivator(SRC)gene family members have been suggested to be involved in energy homeostasis,but the impact of SRC-3 ablation on white and brown adipose tissue needs to be elucidated.In the current study,we collected in vivo data and carried out morphological studies on the effect of SRC-3 deficiency on white adipose tissue(WAT)and brown adipose tissue(BAT).Primary cells were cultured to investigate the differentiation ability of both adipocytes.Western blot was applied to detect the expression of master genes governing adipogenesis and thermogenesis.We observed that SRC-3^(–/–)mice were lean,with reduced WAT and decreased serum leptin levels,mainly due to the smaller white adipocyte size caused by impaired adipo-genesis,presented by decreased peroxisome proliferator activated receptor g(PPARg)expression.In the BAT,the lipid droplets decreased significantly in SRC-3^(–/–)mice as demonstrated by histological analysis and electron micro-scopic observation,which could be explained by enhanced thermogenesis.The expression of thermogenic marker gene PPARg coactivator 1αand uncoupling protein-1 increased in BAT of SRC-3^(–/–)mice,which proved our observations.Collectively,these results demonstrate that SRC-3 plays a key role in adipogenesis and energy expenditure.展开更多
基金supported by grants from the National Basic Research Program of China(No.2006CB503904)Natural Science Foundation of China(Grant Nos.30725037 and 30971385)Shanghai Committee for Science and Technology(No.07JC14042).
文摘Obesity is a medical condition in which excess body fat has accumulated to an extent and may have an adverse effect on health,leading to reduced life expec-tancy,impaired energy homeostasis and increased health problems.The p160 steroid receptor coactivator(SRC)gene family members have been suggested to be involved in energy homeostasis,but the impact of SRC-3 ablation on white and brown adipose tissue needs to be elucidated.In the current study,we collected in vivo data and carried out morphological studies on the effect of SRC-3 deficiency on white adipose tissue(WAT)and brown adipose tissue(BAT).Primary cells were cultured to investigate the differentiation ability of both adipocytes.Western blot was applied to detect the expression of master genes governing adipogenesis and thermogenesis.We observed that SRC-3^(–/–)mice were lean,with reduced WAT and decreased serum leptin levels,mainly due to the smaller white adipocyte size caused by impaired adipo-genesis,presented by decreased peroxisome proliferator activated receptor g(PPARg)expression.In the BAT,the lipid droplets decreased significantly in SRC-3^(–/–)mice as demonstrated by histological analysis and electron micro-scopic observation,which could be explained by enhanced thermogenesis.The expression of thermogenic marker gene PPARg coactivator 1αand uncoupling protein-1 increased in BAT of SRC-3^(–/–)mice,which proved our observations.Collectively,these results demonstrate that SRC-3 plays a key role in adipogenesis and energy expenditure.