肌肽及肌肽酶基因多态性与糖尿病肾病

Carnosine, carnosinase gene polymorphism and diabetic nephropathy

肌肽是一种广泛存在于组织中的内源性二肽，可通过抗氧自由基、减少晚期糖基化终末产物、抑制生长因子的产生和抑制肾素一血管紧张素系统等作用，降低肾小球毛细血管基底膜增厚和肾小球硬化，被认为是糖尿病肾病的保护因子。肌肽在体内主要通过肌肽酶水解，后者主要由CNDPI及CNDP2两种基因编码。已有多项研究显示肌肽酶基因多态性可能影响肌肽酶的水平和活性，目前相关研究主要集中于CNDPI第2外显子区的（CTG）n。对肌肽及肌肽酶基因多态性分子机制的研究，可能为糖尿病肾病的预防、诊断及治疗提供一条新途径。

Carnosine is an endogenously synthesized dipeptide commonly present in mammalian tissue,which can inhibit the thickening of glomerular capillary basement membrane and glomerular sclerosis by scavenging free oxygen radical, inhibiting formation of advanced glycation end products and cytokines, and in- hibiting the renin-angiotensin system. It is considered as a protective factor for diabetic nephropathy. Carnosine is degraded predominantly by carnosinase which is coded by CNDP1 and CNDP2. Several studies have shown that the carnosinase gene polymorphism may affect the level and activities of camosinase, and the current researches have focused on the （CTG） n in CNDP1 exon 2. Studying on the molecular biological mechanisms of camosine and carnosinase may provide a new pathway to prevent,diagnose, and treat diabetic nephropathy.