基于胞外信号调节激酶/胞浆型磷脂酶A2信号通路分析川穹嗪对膜性肾病大鼠肾保护作用

Study on renal protection effect of tetramethylpyrazine on membranous nephropathy rats based on extracellular signal-regulated kinase/cytosolic phospholipase A2 signaling pathway

目的探讨川穹嗪(TMP)对膜性肾病大鼠肾功能的影响,并分析其与胞外信号调节激酶(ERK)/胞浆型磷脂酶A2(cPLA2)信号通路的相关性。方法用阳离子化血清蛋白皮下注射制备膜性肾病大鼠模型,分为模型组、实验组,每组10只,实验组腹腔注射TMP(100 mg·kg-1),模型组腹腔注射等体积生理盐水,隔日注射一次,连续4周,另选10只SD大鼠不做处理作为对照组。用酶联免疫吸附(ELISA)法检测炎性因子水平,用免疫印迹(Western blotting)法检测肾组织细胞凋亡、ERK/cPLA2信号通路相关蛋白水平。结果对照组、模型组、实验组的白介素-1β(IL^-1β)含量分别为(2.79±0.35),(6.95±0.52),(4.13±0.48)ng·L^-1;白介素-6(IL-6)含量分别为(42.25±3.55),(69.41±7.05),(52.36±6.18)ng·L^-1;肿瘤坏死因子-ɑ(TNF-ɑ)含量分别为(40.52±4.58),(66.38±6.56),(55.25±5.85)ng·L^-1;Bax蛋白相对表达量分别为0.26±0.08,0.68±0.10,0.43±0.13;Bcl-2蛋白相对表达量分别为0.72±0.12,0.23±0.03,0.47±0.18;p-ERK1/2蛋白相对表达量分别为0.23±0.04,0.75±0.06,0.45±0.05;p-cPLA2蛋白相对表达量分别为0.19±0.02,0.67±0.05,0.51±0.04;对照组与模型组比较、模型组与实验组比较,上述指标的差异均有统计学意义(均P<0.05)。结论TMP可以减低膜性肾病大鼠的炎性反应、细胞凋亡进而实现其肾保护作用,可能与抑制ERK/cPLA2信号通路有关。

Objective To investigate the effects of tetramethylpyrazine(TMP)on renal function in rats with membranous nephropathy(MN),and to analyze its correlation with extracellular signal-regulated kinase(ERK)/cytosolic phospholipase A2(cPLA2)signaling pathway.Methods MN rat models were prepared by cationized serum protein.They were divided into model group and experimental group,each group with 10 rats.The experimental group was intraperitoneally injected with TMP(100 mg·kg-1),while model group was intraperitoneally injected with same volume of normal saline,once/alternate day for 4 weeks.Another 10 rats without any treatment were enrolled as control group.The levels of inflammatory factors were detected by enzyme-linked immunosorbent assay(ELISA).The levels of renal tissue apoptosis and ERK/cPLA2 signaling pathway related proteins were detected by Western blotting.Results In control group,model group and experimental group,the levels of interleukin-1β(IL^-1β)were(2.79±0.35),(6.95±0.52)and(4.13±0.48)ng·L^-1,respectively;The levels of interleukin-6(IL-6)were(42.25±3.55),(69.41±7.05)and(52.36±6.18)ng·L^-1,respectively;The contents of tumor necrosis factor-ɑ(TNF-ɑ)were(40.52±4.58),(66.38±6.56)and(55.25±5.85)ng·L^-1,respectively;The relative expression of Bax protein were 0.26±0.08,0.68±0.10 and 0.43±0.13,respectively;The relative expression of Bcl-2 protein were 0.72±0.12,0.23±0.03 and 0.47±0.18,respectively;The relative expression of p-ERK1/2 protein were 0.23±0.04,0.75±0.06 and 0.45±0.05,respectively;The relative expression of p-cPLA2 protein were 0.19±0.02,0.67±0.05 and 0.51±0.04,respectively.There were significant differences of the above indexes between control group and model group or model group and experimental group(P<0.05).Conclusion:TMP can reduce inflammatory response and apoptosis of MN rats,and thus achieving renal protection roles,which may be related to inhibition of ERK/cPLA2 signaling pathway.