视黄醇结合蛋白4与脂肪酸合成酶及肝脂肪酶的相关研究

Association of retinol binding protein 4 with fatty acid synthase and hepatic lipase

目的研究视黄醇结合蛋白4(RBP4)对脂肪酸合成酶及肝脂肪酶的影响。方法用不同质量浓度(0、10、100及1 000 ng/mL)RBP4培养基干预肝母细胞癌(HepG2)细胞,采用实时定量聚合酶链反应(RT-PCR)检测脂肪酸合成酶(FAS)及肝脂肪酶(HL)基因mRNA表达水平,采用分光光度法分析FAS及HL活性。结果①不同质量浓度RBP4处理12 h后,100 ng/mL RBP4处理组HepG2细胞FAS mRNA表达较对照组有升高趋势(P=0.087);以100 ng/mL RBP4处理12 h后的HepG2细胞FAS mRNA表达较培养1 h显著升高(P<0.05);培养24 h较培养1 h有升高趋势(P=0.098)。②不同质量浓度,RBP4刺激HepG2细胞10 min后,1 000 ng/mL RBP4处理组HL mRNA表达较对照组及10、100 ng/mL RBP4处理组显著升高(P值分别<0.01、0.05);20 min后,1 000及10 ng/mL RBP4处理组较对照组显著升高(P值均<0.01);30 min后,各组间的差异无统计学意义(P>0.05)。③HepG2细胞体外培养给予不同质量浓度RBP4孵育24 h后,10、1 000 ng/mL RBP4处理组的FAS酶活性均较对照组显著升高(P值均<0.05),随着RBP4浓度升高FAS酶活性呈升高趋势;而HL酶活性无明显变化。结论 100 ng/mL RBP4能增加FAS mRNA的表达,RBP4可能影响FAS酶活性,FAS酶活性随着RBP4质量浓度的增加有增强趋势。高质量浓度RBP4短时间干预可增加HepG2细胞HL mRNA的表达,未见RBP4对HL酶活性有影响。

Objective To investigate the effect of serum retinol binding protein 4（RBP4） on fatty acid synthase （FAS） and hepatic lipase （HL）. Methods HepG2 cells were cultured with the different concentrations of RBP4 in medium （control group, 10, 100 and 1 000 ng/mL）. Fluorescent real-time polymerase chain reaction （RT-PCR） was used to determine the mRNA expression of FAS and HL genes in HepG2 cells of different groups. The activities of the FAS and HL were measured by spectrophotometric method. Results （1） The expression of FAS mRNA had an increasing tendency in 100 ng/ml RBP4 treatment group than that in control group at 12 h （P = 0. 087）. We found that the expression of FAS and HL at 12 h after treatment was significantly higher than those at 1 h in 100 ng/mL RBP4 group （P〈0. 05）. （2） 10 min later, the expression of HL mRNA had an increasing tendency in 1,000 ng/mL RBP4 group compared with control and group 10,100 ng/mL RBP4 group at 10 min （ P〈0.01,0.05）. 20 min later, the levels in 1,000 and 10 ng/mL RBP4 groups were significantly higher than that of the control group （P〈0.01）. 30 min later, there were no significant differences among different groups. （3） When cultured with different concentrations of RBP4 for 24 h, FAS activity significantly increased in 10 and 1,000 ng/mL RBP4 group than in the control group （P〈0.05）. FAS activity showed an increasing trend as RBP4 concentrationincreased; and no significant difference was found in HL activity. Conclusions RBP4 （100 ng/mL） can increase FAS mRNA expression. FAS activity has an increasing trend with the increase of RBP4 concentration. High concentrations of RBP4 can increase the expression of HL, but has no influence on HL activity. （Shanghai Med J, 2011, 34; 360-363）