甜菜碱对db/db小鼠糖尿病肾病损伤的作用

Effects of Betaine on Diabetic Nephropathy in db/db Mice

为探究甜菜碱对db/db小鼠糖尿病肾病损伤的保护作用,将7月龄db/db小鼠随机分为模型组(生理盐水),阳性对照组(脂必妥),甜菜碱低剂量组(200 mg/kg)、中剂量组(400 mg/kg)、高剂量组(800 mg/kg)。所有小鼠均饲以高脂饲料,以诱发糖尿病肾病(DN)模型。以甜菜碱连续灌胃6周后,进行肾组织病理学观察,并检测小鼠体重,血清中血尿素氮(BUN)、血糖(GLU),总胆固醇(TC),甘油三酯(TG)、低密度脂蛋白(LDL)、转化生长因子-β1(TGF-β1)与肿瘤坏死因子-α(TNF-α)的水平。结果显示,甜菜碱处理组与模型组相比,肾小球基底膜无明显增厚,细胞外基质、糖原物质沉积及纤维含量减少,蛋白管型和炎性细胞浸润基本消失,肾小管结构逐渐恢复正常,体重和BUN、GLU、TC、TG、LDL、TNF-α、TGF-β1水平均显著降低(P<0.05),最高分别降低11.5 g、3.0 mM、5.3 mM、3.1 mM、0.42 mM、0.64 mM、21 ng/L、30 ng/L。表明甜菜碱对db/db小鼠具有降糖、降脂、改善肾功能的生理作用,能延缓或抑制糖尿病肾病微血管炎症过程。

To evaluate the protective effects of betaine on diabetic nephropathy（DN） in db/db mice,7 months old db/db mice were randomly divided into negative control group（physiological saline）,positive control group（Zhibituo）,low（200 mg/kg）,middle（400 mg/kg） and high dose（800 mg/kg） betaine group.The mice were fed by high-fat diet to induce DN.After being intragastric administrated by betaines for 6 weeks,the kidney paraffin sections were prepared and the pathological changes were analyzed based on staining,the body weight and BUN,GLU,TC,TG,LDL,TNF-α,TGF-β1 level were also investigated.The results showed that the glomerular basement membrane in the betaine and Zhibituo treatment group did not thicken;extracellular matrix,the glycogen material deposition and fiber content reduced;protein casts and inflammatory cell infiltration disappeared.Furthermore,the structure of renal tubule gradually returned to normal;the body weight and BUN,GLU,TG,TC,LDL,TNF-α,TGF-β1 level were significantly decreased（P 〈 0.05） by 11.5 g,3.0 mM,5.3 mM,3.1 mM,0.42 mM,0.64 mM,21 ng/L and 30 ng/L,respectively.It can be speculated that betaine has a hypoglycemic activity,lipid-lowering effect,and protective effect on the kidney injury of db/db mice.It may delay or inhibit the inflammatory process of the capillary vessel in diabetic nephropathy.