姜黄素在脓毒血症幼鼠急性肾损伤中的炎症调节机制

Inflammatory regulatory mechanism of curcumin in acute kidney injury in young rats with sepsis

目的探讨姜黄素(Curcumin)对脓毒血症(Sepsis)幼鼠急性肾损伤的保护作用及机制。方法40只SD幼鼠按照随机数字表法分为4组,假手术组(Sham组)、盲肠结扎穿孔模型组(Cecal ligation and puncture,CLP组)、CLP+姜黄素高剂量组(100mg/kg)及CLP+姜黄素低剂量组(50mg/kg),每组10只。CLP+姜黄素组在造模前1周给予姜黄素悬浊液2.0mL每天灌胃一次,Sham组和CLP组造模前1周给予生理盐水2.0mL每天灌胃一次。除Sham组外均需建立CLP模型,手术成功后24h,腹腔注射麻醉后,取下腔静脉血,采用ELISA法检测血清中肌酐(Scr)、尿素氮(BUN)、中性粒细胞明胶酶相关脂质运载蛋白(NGAL)和炎症因子白介素-18(IL-18)、白介素-1β(IL-1β)。取左、右肾的上半部分组织采用HE染色法观察肾脏病理组织学变化,取左、右肾的下半部分组织通过蛋白免疫印迹法检测NF-κB p65及其下游炎性小体NLRP3、Caspase-1相关蛋白表达。结果与CLP组相比较,姜黄素干预组可减低肾脏病理损伤,降低Scr、BUN及炎症因子IL-18、IL-1β水平(P<0.01),CLP组与Sham组相比NF-κB p65蛋白表达量明显增加(P<0.05),姜黄素组相对于CLP组NF-κB p65蛋白表达量相对减少(P<0.01),高剂量姜黄素组与低剂量姜黄素组相比下调了NF-κB p65、NLRP3、Caspase-1蛋白表达水平(P<0.01)。结论高剂量姜黄素能改善脓毒血症幼鼠的肾功能,其机制可能是其调节NLRP3(Caspase-1)-NF-κB,抑制IL-1β、IL-18,降低炎症反应,进而改善脓毒血症幼鼠相关的急性肾损伤。

Objective To investigate the protective effect and mechanism of curcumin on acute kidney injury in rats with sepsis.Methods Forty SD rats were randomly divided into 4 groups with 10 rats in each group.Sham group,cecal ligation andpuncture model group(CLP group),CLP+curcumin high-dose group(100mg/kg)and CLP+curcumin low-dose group(50mg/kg).The CLP+curcumin group was given curcumin suspension 2.0mL once a day by gavage 1 week before modeling,while the sham and CLP groups were given normal saline 2.0mL once a day by gavage 1 week before modeling.CLP model was established for all rats except the sham group.Twenty-four hours after the successful operation,inferior vena cave blood was obtained after intraperitoneal injection anesthesia.Serum creatinine(Scr),urea nitrogen(BUN),neutrophil gelatinase-associated lipocalin(NGAL)and inflammatory factors interleukin-18(IL-18)and interleukin-1β(IL-1β)were detected by ELISA.The histopathological changes of the upper part of the left and right kidneys were observed by HE staining.The expressions of NF-κB p65 and its downstream inflammasome NLRP3 and caspase-1 were detected by Western blot.Results Compared with the CLP group,the curcumin group could reduce renal pathological damage,reduce the levels of Scr,BUN and inflammatory factors IL-18 and IL-1β(P<0.01).Compared with the sham group,the expression of NF-κB P65 protein in the CLP group was significantly increased(P<0.05).The protein expression of NF-κB p65 in the curcumin group was decreased compared with that in the CLP group(P<0.01).The protein expression of NF-κB p65,NLRP3 and caspase-1 in the high-dose curcumin group was down-regulated compared with that in the low-dose curcumin group(P<0.01).Conclusion High-dose curcumin may regulate NLRP3(caspase-1)-NF-κB,inhibite IL-1βand IL-18,and reduce of inflammatory response,which improve acute kidney injury associated with sepsis in young rats.