维生素D对2型糖尿病肾病大鼠肾脏中转化生长因子-β1、重组人胶原蛋白-1 和结缔组织生长因子表达的影响

目的探讨维生素D对糖尿病肾病大鼠转化生长因子-β1（TGF—β1）、结缔组织生长因子（CTGF）和重组人胶原蛋白-1（collagen-1）表达的影响，进一步探讨以上3个基因在糖尿病肾病中相互作用以及维生素D对糖尿病肾病大鼠肾脏的保护作用。方法将54只雄性SD大鼠按随机数字表法分为正常对照组（18只）、模型组（18只）、治疗组（18只）。其中，模型组及治疗组大鼠均行糖尿病肾病造模，饲以高脂高糖饲料6周，空腹12h后给予小剂量链腺佐菌素腹腔注射。注射1周后，不同日期测随机血糖（GLU）3次，若3次GLU均≥16．7mmol／L为2型糖尿病大鼠。2型糖尿病成模后的大鼠在6周和7周时用尿微量蛋白试纸连续测大鼠晨尿3次以上，若为阳性，则为2型糖尿病肾病的大鼠。治疗组给予骨化三醇溶于0．05mL花生油以0．03μg／（kg·d）灌胃37d，模型组给予花生油灌胃37d。处死大鼠，取肾脏，采用HE、电镜技术观测。肾脏组织的形态学变化，采用实时荧光定量PCR技术（RT—PCR）评价肾脏TGF—β1、collagen-1及CTGF基因表达的变化。结果①模型组TGF—β1、collagen-1及CTGF基因表达高于正常对照组（P〈0．05），治疗组TGF—β1、collagen-1及CTGF基因表达明显低于模型组（P〈0．05）。②采用HE、电镜技术可以看出治疗组病理组织形态学，尤其是组织结构完整性明显优于模型组。结论糖尿病。肾病大鼠中，维生素D可以通过下调TGF—β1、collagen-1及CTGF基因的表达，对糖尿病肾病起保护作用。

Effect of vitamin D on the expression of growth factor growth factor beta 1, recombinant human collagen-1 and connective tissue growth factor in kidney of rats with type 2 diabetic nephropathy

Objective To explore the effect of vitamin D on the expression of transforming growth factor-β1 （TGF-β1）, connective tissue growth factor （CTGF） and restructuring of collagen-1 （collagen-1） in diabetic nephropathy rat, discuss their interaction in diabetic nephropathy, and the protective effect of vitamin D for the kidney of diabetic nephropathy rat. Methods 54 male SD rats were randomly divided into three groups： normal control group （n=18）, model group （n= 18）, treatment group （n=18）. The model group and treatment group rats were established diabetic nephropathy model, and fed with high fat diet for 6 weeks, then intraperitoneal injection of small dose streptozotocin after fasting for 12 hours. 1 week after injection, 3 times of blood glucose （GLU） on a different date were measured, if 3 times of GLU all ≥ 16.7 mmol/L indicated that rats had type 2 diabetes mellitus. 6 and 7 weeks after type 2 diabetes mellitus model es- tablishment, trace protein urine dipstick was used for detection of the morning urine of rats for at least 3 times, if theresults were positive, indicated that rats had type 2 dia- betic nephropathy. The treatment group was given 0.03 μg/（kg·d） calcitriol dissolved in 0.05 mL peanut oil by intragastric administration for 37 d. The model group was given peanut oil by intragastric administration for 37 d. After treatment all rats were killed, and the kidneys were removed. HE, electron microscopy were used formorphological changes observation of renal tissue, real-time fluorescence quantitative PCR （RT-PCR） was used for e- valuation of expression changes of renal TGF-β1, collagen-1 and CTGF genes. Results ①The expression of TGF-β1, collagen-1 and CTGF genes in the model group were significantly higher than those in the normal control group （P 〈 0.05）, which in the treatment group were significantly lower than those in the model group （P 〈 0.05）.②The results of HE, electron microscopy showed that in the treatment group the pathological tissue morphology, especially organization- al structure integrity was better than that of model group significantly. Conclusion Vitamin D can down regulate the expression of TGF- β1, collagen-1 and CTGF genes, has protective effect on diabetic nephropathy for the diabetic nephropathy rats.