雷公藤多苷通过NLRP3/caspase-1/GSDMD细胞焦亡通路对糖尿病肾病大鼠肾损伤的影响

Effect of multi-glycosides of Tripterygium wilfordii on renal injury in diabetic kidney disease rats through NLRP3/caspase-1/GSDMD pyroptosis pathway

探讨雷公藤多苷(multi-glycosides of Tripterygium wilfordii,GTW)通过Nod样受体蛋白3(Nod-like receptor protein 3,NLRP3)/半胱氨酸天冬氨酸蛋白水解酶-1(caspase-1)/消皮素D(GSDMD)细胞焦亡通路改善糖尿病肾病(diabetic kidney di-sease,DKD)大鼠肾损伤的作用和机制。将42只雄性SD大鼠随机分为正常组8只、造模组34只。造模组予以高糖高脂饮食及一次性腹腔注射链脲佐菌素(streptozotocin,STZ),诱导建立DKD大鼠模型。造模成功后随机分为模型组、缬沙坦(代文)组、雷公藤多苷(GTW)组。正常组及模型组灌服生理盐水,治疗组分别予以代文和GTW连续灌胃6周后,生化检测各组大鼠血尿素氮(blood urea nitrogen,BUN)、血肌酐(serum creatinine,Scr)、谷丙转氨酶(alanine aminotransferase,ALT)、血清白蛋白(albumin,ALB)及24 h尿蛋白定量(24 hours urinary total protein,24 h-UTP)水平;苏木素-伊红(hematoxylin-eosin,HE)染色观察肾组织病理;酶联免疫吸附测定法(enzyme-linked immunosorbent assay,ELISA)检测血清白细胞介素-1β(interleukin-1β,IL-1β)、白细胞介素-18(interleukin-18,IL-18)水平;蛋白免疫印迹法(Western blot)检测肾组织中细胞焦亡通路相关蛋白表达;RT-PCR检测肾组织中细胞焦亡通路相关基因表达。与正常组比较,模型组大鼠BUN、Scr、ALT、24 h-UTP及血清IL-1β、IL-18水平均显著升高(P<0.01),ALB显著降低(P<0.01),肾脏病理损伤较重,且肾组织NLRP3、caspase-1、GSDMD蛋白及其mRNA表达水平显著升高(P<0.01);与模型组比较,代文组、GTW组BUN、Scr、ALT、24 h-UTP及血清IL-1β、IL-18水平均显著下降(P<0.01),ALB显著升高(P<0.01),肾脏病理改善,且肾组织NLRP3、caspase-1、GSDMD蛋白及其mRNA表达水平明显降低(P<0.01或P<0.05)。GTW可能通过降低NLRP3/caspase-1/GSDMD在肾组织的表达抑制细胞焦亡,缓解DKD大鼠炎症反应,减轻肾脏病理损伤。

This study investigated the effect of multi-glycosides of Tripterygium wilfordii(GTW)on renal injury in diabetic kidney disease(DKD)rats through Nod-like receptor protein 3(NLRP3)/cysteine-aspartic acid protease-1(caspase-1)/gsdermin D(GSDMD)pyroptosis pathway and the mechanism.To be specific,a total of 40 male SD rats were randomized into the control group(n=8)and modeling group(n=34).In the modeling group,a high-sugar and high-fat diet and one-time intraperitoneal injection of streptozotocin(STZ)were used to induce DKD in rats.After successful modeling,they were randomly classified into model group,valsartan(Diovan)group,and GTW group.Control group and model group were given normal saline,and the valsartan group and GTW group received(ig)valsartan and GTW,respectively,for 6 weeks.Blood urea nitrogen(BUN),serum creatinine(Scr),alanine aminotransferase(ALT),albumin(ALB),and 24-hour urinary protein(24 h-UTP)were determined by biochemical tests.The pathological changes of renal tissue were observed based on hematoxylin and eosin(HE)staining.Serum levels of interleukin-1β(IL-1β)and interleukin-18(IL-18)were detected by enzyme-linked immunosorbent assay(ELISA).Western blotting was used to detect the expression of pyroptosis pathway-related proteins in renal tissue,and reverse transcription-polymerase chain reaction(RT-PCR)to determine the expression of pyroptosis pathway-related genes in renal tissue.Compared with the control group,the model group showed high levels of BUN,Scr,ALT,and 24 h-UTP and serum levels of IL-1βand IL-18(P<0.01),low level of ALB(P<0.01),severe pathological damage to kidney(P<0.01),and high protein and mRNA levels of NLRP3,caspase-1,and GSDMD in renal tissue(P<0.01).Compared with the model group,valsartan group,and GTW group had low levels of BUN,Scr,ALT,and 24 h-UTP and serum levels of IL-1βand IL-18(P<0.01),high level of ALB(P<0.01),alleviation of the pathological damage to the kidney,and low protein and mRNA levels of NLRP3,caspase-1,and GSDMD in renal tissue(P<0.01 or P<0.05).GTW may inhibit pyroptosis by decreasing the expression of NLRP3/caspase-1/GSDMD in renal tissue,thereby relieving the inflammatory response of DKD rats and the pathological injury of kidney.