晚期糖基化终产物对脂肪细胞产生活性氧的诱导作用及其机制

Advanced glycosylation end products induce production of reactive oxygen species in adipocytes and the mechanism

目的观察晚期糖基化终产物(AGEs)对脂肪细胞产生活性氧(ROS)的影响及机制。方法 3T3-L1前脂肪细胞体外培养并诱导分化为成熟的脂肪细胞,以小鼠血清白蛋白(MSA)作为阴性对照,用不同浓度(25、50、100μg/mL)AGEs共同孵育不同时间(0、5、15、30 min及1、3 h)后,荧光探针2',7'-二氯荧光素乙二酯测定细胞ROS生成水平,间接反映ROS的产生量。分别应用酶特异性抑制剂预处理脂肪细胞,观察AGEs-MSA刺激脂肪细胞生成ROS的变化。结果 AGEs能诱导脂肪细胞产生ROS,ROS的产生量随MSA氧化程度的升高和AGEs-MSA浓度的增加而增多。AGEs诱导脂肪细胞产生的超氧阴离子能被NADPH氧化酶的阻断剂DPI和apocynin明显抑制,不能被其他酶的阻断剂所抑制。结论 AGEs能够诱导脂肪细胞产生ROS,其部分机制可能与NADPH氧化酶激活有关。

Objective To investigate the mechanism of advanced glycosylafion end products （AGEs） inducing the production of reactive oxygen species （ROS） in adipocytes. Methods The 3T3 - L1 adipocytes were cultured and differentiated into mature adipocytes in vitro. Cultured adipocytes were incubated with indicated concentrations （25, 50 and 100 fxg/mL） of AGEs - modified murine serum albumin （MSA） for 1 h, or treated with 100 mg/mL of AGEs - MSA for the indicated durations （0, 5, 15, 30, 60 and 180 min）. The production of ROS was determined by fluorescence probe DCFHDA. To clarify the underlying mechanism of AGEs - induced ROS production, adipocytes were preincubated for 1 h with the inhibitors of various enzymatic systems involved in ROS generation. The changes of ROS production were detected. Results Compared with cells incubated with medium alone or native MSA, AGEs - MSA induced ROS production in adipocytes in time - and dose - dependent manners, and the quantity of ROS increased with the oxidation degree of MSA. The AGEs -triggered ROS generation was significantly suppressed by pretreatment with apocynin and DPI, the inhibitors of NADPH oxidase; but not the other inhibitors. Conclusion AGEs - MSA induces ROS production in adipocytes, partially mediated by NADPH oxidase activation.