马兜铃酸对人肾小管细胞分泌性磷脂酶A_2的影响

Investigation of Aristolochic Acid on Secretory Phospholipase A_2 of Human Kidney Cell in Vitro

目的:研究马兜铃酸(aristolochic acid,AA)对人肾小管细胞(human kidney cell,HKC)的损伤与分泌性磷脂酶A2(secretory phospholipase A2,sPLA2)活性的影响。方法:以体外培养的HKC为研究对象,脂多糖(LPS)和氯化钙(CaCl2)为sPLA2激活剂,将实验分为单用AA组和联用激活剂组两大类,用sPLA2活性检测试剂盒检测上清中sPLA2活性改变。结果:10 mg/L AA刺激HKC 24 h后,引起细胞上清sPLA2活性降低(1.154±0.079 vs 1.389±0.123),与正常对照组比较无统计学意义。随着AA剂量的增大,sPLA2活性升高,40 mg/L时高达5.422±0.091(P<0.05),且40 mg/L AA培养组sPLA2活性表现出与时间呈正相关的变化。2LPS和CaCl2剂量正相关地激活HKC sPLA2,该过程可为10 mg/L AA所抑制,呈浓度依赖性。结论:10 mg/L AA可抑制LPS和CaCl2激活HKC sPLA2,呈浓度正相关性。同时,较高浓度AA可损伤HKC激活sPLA2。据此,推测AA损伤HKC的过程中,sPLA2活性达不到损伤程度应有的水平。

Objective：To investigate the effect of aristolochic acid on secretory Phospholipase A2 （sPLA2） activity of human kidney cells （HKCs） in vitro. Methods： HKCs were cultured with aristolochic acid （AA） and/or sPLA2 agonists including lipopolysaccharide （LPS） and CaCl2. sPLA2 activity in the supernatant of HKCs was determined with sPLA2 assay kit. Results：Compared with the normal group, sPLA2 activity in the supernatant of 10 mg/L group decreased slightly（ P 〉0.05 ）while sPLA2 activity increased markedly in AA 20 mg/L and 40 mg/L treated HKC groups. There was positive correlation between sPLA2 activity and AA concentration （ 10-40 rng/L, r = 0. 923, P 〈 0.01 ）, or cultured time （40 mg/L AA, 12 h-48 h, r = 0. 797, P 〈 0.01 ） significantly. 2. AA inhibited sPLAz activated by 1 200 μmml/L CaCIz or 1 200 ng/ml LPS in a concentration - dependent manner. （ r = 0. 765, P〈 0.01 and r = 0. 936, P〈 0.01, repectively）. Conclusion： AA inhibited sPLAz activated by LPS or CaCl2 in a concentration- dependent manner. In the meantime, AA （concentration≥20 mg/L） could damage sPLA2 activiation by HKC. So we concluded that, sPLA2 activity cannot reach what the damage should have, when there is an aristolochic acid nephropathy.