瞬时受体电位离子通道3在糖尿病肾病小鼠的表达及意义

Expression of transient receptor potential melastatin 3 in diabetic nephropathy mice

目的:研究瞬时受体电位离子通道3(TRPM3)在2型糖尿病肾病模型db/db小鼠肾组织的表达,以及高糖对人肾小管上皮细胞(HK2)和小鼠足细胞(MPC)TRPM3表达的影响。方法:(1)将20只雄性5周龄db/db小鼠随机分为两组,各10只。同窝出生的db/m小鼠作为正常对照组(n=20)。待db/db小鼠生长至10周龄和18周龄后取血、尿标本测定相关生化指标,留取肾组织。利用Western blot、实时荧光定量PCR(qRT-PCR)和免疫组织化学方法,检测正常对照组(db/m小鼠)及不同周龄(10周、18周)db/db小鼠肾组织中TRPM3的表达水平及分布情况。(2)体外培养HK2和条件永生化MPC,分别按以下处理分组:对照组(D-葡萄糖5.6 mmol/L);甘露醇组(D-葡萄糖5.6 mmol/L+甘露醇24.4 mmol/L);高糖组(D-葡萄糖30 mmol/L),培养24h、48h、72h收获细胞,用Western blot和qRT-PCR检测细胞中TRPM3的表达。结果:(1)与db/m小鼠相比,db/db小鼠肾组织肾小管和肾小球中TRPM3的表达增多,差异有统计学意义(P<0.05);(2)与正常对照组相比,高糖组HK2和MPC中TRPM3的表达均增多,差异有统计学意义(P<0.05);结论:TRPM3可表达于糖尿病肾病小鼠肾脏组织的肾小管和肾小球中,且高血糖可诱导TRPM3在HK2细胞和MPC细胞的高表达;TRPM3可能参与了糖尿病肾病的发生发展。

Objective：To study the expression of transient receptor potential melastatin 3 （TRPM3） in the internationally recognized db/db mouse model of type 2 diabetic nephropathy, in human tubular epithelial cells （HK2） and conditionally immortalized mouse podoeytes （MPC） under high glucose. Methodology：Twenty male five-week db/db mice were randomly divided into two groups （each n= 10）, and we used db/m mice of littcrmate as the normal control group （n = 20）. At the age of 10 weeks and 18 weeks, the samples of blood, urine and renal tissues were colltected. The biochemical indexes were measured. The expression of TRPM3 in renal tissues was assessed by Western blot,qRT-PCR and immunohistochemistry respectively. HK2 and MPC were cultured in vitro and divided into the following groups ： （1 ） Normal control group （D-glucose 5.6 mmol/L） ; （2） Mannitol group （D-glucose 5.6 mmol/L＋D-mannitol 24. 4 mmol/L） ; （3） High glucose group （ D-glucose 30 mmol/L）. The corresponding indexes were measured at 24th, 48th and 72th hour. Western blot and qRT-PCR were used to examine the expression of TRPM3 in protein and mRNA. Results ： Compared with the 10w db/m mice, the expression of TRPM3 in the 10w db/db and 18w db/db mice was increased significantly （P〈 0. 05）. In cultured HK2 and MPC, the protein and mRNA expression of TRPM3 was increased in High glucose group, compared with the normal control group （ P 〈 0.05 ）. Conclusion： TRPM3 can be expressed in the renal tubules and glomerulus of mouse, and high glucose can induce the higher expression of TRPM3 in HK2 and MPC. TRPM3 may be involved in the development of diabetic nephropathy.