Objective To verify the regulation of acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT 2), which is associated with cholesterol metabolism, by saturated fatty acids (SFAs). Methods Palmitic acid (PA), the most abun...Objective To verify the regulation of acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT 2), which is associated with cholesterol metabolism, by saturated fatty acids (SFAs). Methods Palmitic acid (PA), the most abundant saturated fatty acid in plasma, and oleic acid (OA), a widely distributed unsaturated fatty acid, were used to treat hepatic cells HepG2, HuH7, and mouse primary hepatocytes. In addition, PA at different concentrations and PA treatment at different durations were applied in HepG2 cells. In in vivo experiment, three-month male C57/BL6 mice were fed with control diet and SFA diet containing hydrogenated coconut oil rich of SFAs. The mRNA level of ACAT2 in those hepatic cells and the mouse livers was detected with real-time polymerase chain reaction (PCR). Results In the three types of hepatic cells treated with PA, that SFA induced significant increase of ACAT2 expression (P<0.01), whereas treatment with OA showed no significant effect. That effect of PA was noticed gradually rising along with the increase of PA concentration and the extension of PA treatment duration (both P<0.05). SFA diet feeding in mice resulted in a short-term and transient increase of ACAT2 expression in vivo, with a peak level appearing in the mice fed with SFA diet for two days (P<0.05). Conclusion SFA may regulate ACAT2 expression in human and mouse hepatic cells and in mouse livers.展开更多
Objective： To investigate the effects of rosiglitazone, a synthetic ligand of peroxisome proliferators-activated receptor gamma （PPARγ）, on the expression of acyl-coenzyme A： cholesterol acyltransferase-1 （ACAT-...Objective： To investigate the effects of rosiglitazone, a synthetic ligand of peroxisome proliferators-activated receptor gamma （PPARγ）, on the expression of acyl-coenzyme A： cholesterol acyltransferase-1 （ACAT-1） in phorbol myristate acetate （PMA）-pretreated THP-1 cells after the inducement of advanced glycation end products （AGEs）. Methods： After THP-1 cells were cultured in the presence of 0.1 μmol/L PMA for 72 h to induce phagocytic differentiation, the obtained THP-1 macrophages were treated with rosiglitazone for 4 h at different concentrations （1, 5 or 10 μmol/L） and then exposed to AGEs-modified bovine serum albumin （AGEs-BSA） for 24 h at a concentration of 200 mg/L. Reverse transcription polymerase chain reaction （RT-PCR） and Western blot analysis were performed to detect the mRNA and protein expressions of ACAT-1 respectively. Results： Administration of AGEs-BSA （200 mg/L） into the THP-1 macrophages resulted in up-regulation of ACAT-1 at mRNA and protein levels when compared with the expressions in macrophages incubated with serum-free RPMI1640. Pretreatment of rosiglitazone inhibited significantly the increased expression of ACAT-1 induced by AGEs-BSA in a concentration-dependent manner. Conclusion： PPARy activation by rosiglitazone down-regulates ACAT-1 expression induced by AGEs in THP-1 macrophages, which might provide a new way for treating atherogenesis in diabetic patients.展开更多
基金Supported by National Natural Science Foundation of China (30721063)National High Technology Research and Development Program of China (863 Program) (2006AA02A406)+1 种基金National Basic Research Program of China (973 Program) (2006CB503801)Special Fund of the National Laboratory of China (2060204)
文摘Objective To verify the regulation of acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT 2), which is associated with cholesterol metabolism, by saturated fatty acids (SFAs). Methods Palmitic acid (PA), the most abundant saturated fatty acid in plasma, and oleic acid (OA), a widely distributed unsaturated fatty acid, were used to treat hepatic cells HepG2, HuH7, and mouse primary hepatocytes. In addition, PA at different concentrations and PA treatment at different durations were applied in HepG2 cells. In in vivo experiment, three-month male C57/BL6 mice were fed with control diet and SFA diet containing hydrogenated coconut oil rich of SFAs. The mRNA level of ACAT2 in those hepatic cells and the mouse livers was detected with real-time polymerase chain reaction (PCR). Results In the three types of hepatic cells treated with PA, that SFA induced significant increase of ACAT2 expression (P<0.01), whereas treatment with OA showed no significant effect. That effect of PA was noticed gradually rising along with the increase of PA concentration and the extension of PA treatment duration (both P<0.05). SFA diet feeding in mice resulted in a short-term and transient increase of ACAT2 expression in vivo, with a peak level appearing in the mice fed with SFA diet for two days (P<0.05). Conclusion SFA may regulate ACAT2 expression in human and mouse hepatic cells and in mouse livers.
文摘Objective： To investigate the effects of rosiglitazone, a synthetic ligand of peroxisome proliferators-activated receptor gamma （PPARγ）, on the expression of acyl-coenzyme A： cholesterol acyltransferase-1 （ACAT-1） in phorbol myristate acetate （PMA）-pretreated THP-1 cells after the inducement of advanced glycation end products （AGEs）. Methods： After THP-1 cells were cultured in the presence of 0.1 μmol/L PMA for 72 h to induce phagocytic differentiation, the obtained THP-1 macrophages were treated with rosiglitazone for 4 h at different concentrations （1, 5 or 10 μmol/L） and then exposed to AGEs-modified bovine serum albumin （AGEs-BSA） for 24 h at a concentration of 200 mg/L. Reverse transcription polymerase chain reaction （RT-PCR） and Western blot analysis were performed to detect the mRNA and protein expressions of ACAT-1 respectively. Results： Administration of AGEs-BSA （200 mg/L） into the THP-1 macrophages resulted in up-regulation of ACAT-1 at mRNA and protein levels when compared with the expressions in macrophages incubated with serum-free RPMI1640. Pretreatment of rosiglitazone inhibited significantly the increased expression of ACAT-1 induced by AGEs-BSA in a concentration-dependent manner. Conclusion： PPARy activation by rosiglitazone down-regulates ACAT-1 expression induced by AGEs in THP-1 macrophages, which might provide a new way for treating atherogenesis in diabetic patients.
