肾衰养真胶囊对慢性肾衰竭营养不良大鼠UPP通路的影响

Effects of Shenshuai Yangzhen Capsule on Ubiquitin Proteasome Pathway in Chronic Renal Failure Rats with Malnutrition

目的观察肾衰养真胶囊对慢性肾衰竭(chronic renal failure,CRF)营养不良大鼠泛素蛋白酶体通路(ubiquitin proteasome pathway,UPP)的影响。方法采用5/6肾切除同时予4%酪蛋白饮食制备CRF营养不良大鼠模型。40只SD大鼠按体重随机分为假手术组、模型组、肾衰养真胶囊组和开同组,每组10只。术后1周肾衰养真胶囊组给予每天肾衰养真胶囊0.28 g/mL灌胃,开同组给予开同片每天0.21 g/mL灌胃,同时模型组予等体积的生理盐水灌胃,假手术组不施加任何干预,持续干预4周。检测肌酐(SCr)、尿素氮(BUN)、24 h尿蛋白(24 h Upro)、白蛋白(Alb)、血红蛋白(Hb)水平,应用免疫组化检测骨骼肌泛素(Ub)蛋白表达,免疫荧光检测骨骼肌肌肉萎缩蛋白(MAFbx)和肌环指蛋白-1(MuRF-1)蛋白表达。结果与假手术组比较,模型组SCr、BUN、24 h Upro水平升高,Alb、Hb水平下降,骨骼肌Ub、MAFbx、MuRF-1蛋白表达水平升高(P<0.01)。与模型组比较,开同组和肾衰养真胶囊组SCr、BUN水平下降,Alb水平升高,Ub、MAFbx、MuRF-1蛋白表达水平下降(P<0.05,P<0.01);肾衰养真胶囊组24 h Upro水平下降,Hb水平升高(P<0.01)。与开同组比较,肾衰养真胶囊组24 h Upro水平下降,BUN、Hb 7水平升高更明显(P<0.05,P<0.01),开同组MAFbx蛋白表达水平较肾衰养真胶囊组下降更明显(P<0.01)。结论肾衰养真胶囊可能通过减少骨骼肌Ub、MAFbx和MuRF-1蛋白表达,从而抑制UPP信号通路的活性,减少蛋白分解,改善CRF营养不良。

Objective To observe the effect of Shenshuai Yangzhen Capsule （SSYZC） on ubiquitin proteasome pathway（UPP） in chronic renal failure （CRF） rats with malnutrition （MN）. Methods CRF-MN model was established by 5/6 nephrectomy and 4% casein diet. Forty SD rats were randomly divided into four groups, the Sham operation group（A）, the model control group（B）, the Ketosteril group（C） and the SSYZC group（D）. One week after surgery, SSYZC was administered by gastrogavage at daily does of 0.28 g/mL to the group D. Ketosteril was administered by gastrogavage at daily does of 0. 21 g/mL to the group C. Equal volume of normal saline was given by gastrogavage to rats in the group B, the group A did not exert any intervention After 4 weeks of treatment, the renal function related indexes, including blood urea nitrogen （BUN）, serum creatinine （SCr）, 24 hours urine protein （24 h Upro）, albumin （AIb）, and haemoglobin （Hb） were detected. The expression of Ub protein, muscle atrophy F box （MAFbx） and Muscle RING-finger protein1 （MuRF-1） in skeletal muscle were determined by immunohistochemistry and immunofluorescence respectively. Results Compared with the group A, the levels of SCr, BUN, 24 h Upro, and protein expression of Ub, MAFbx, MuRF-1 increased, while AIb and Hb decreased in the group B （P 〈0.01 ）. Compared with the group B, the levels of SCr, BUN, and protein expression of Ub, MAFbx, MuRF-1 declined, AIb levels raised in the group C and the group D （P 〈0.05, P 〈0.01 ）, at the same time, the levels of 24 h Upro decreased and Hb increased in the group D（P 〈0.01 ）. The levels of BUN, Hb were significantly higher, and 24 h Upro decreased compared to those of group C （P 〈0.05, P 〈0.01 ）. The MAFbx expression was down-regulated markedly in the group C compared with the group D （P 〈0. 05）. Conclusion SSYZC could improve the MW in rats with CRF through down-regulating Ub, MAFbx and MuRF-1 protein expression, inhibiting the activity of UPP, and reducing protein breakdown.