Wang Jianyun, Yang Qianqian, Nie Yaxing, Guo Hao, Zhang Fan, Zhou Xueyan, Yin Xiaoxing
Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu, China.
J Pharm Pharmacol. 2017 Feb;69(2):182-190. doi: 10.1111/jphp.12677. Epub 2016 Dec 29.
Nitric oxide (NO) plays an important role in the progression of early-stage diabetic nephropathy (DN), which is found to contribute to extracellular matrix (ECM) accumulation in mesangial cells (MCs). As a cofactor for NO production, tetrahydrobiopterin (BH ), a folacin analogue, may be responsible for the ECM accumulation and proliferation of MCs. This study was to investigate the effects of BH on glomerulosclerosis in early-stage DN.
In in vitro studies with cultured mesangial cells and in vivo studies with streptozotocin-induced diabetic rats, BH levels were assayed by HPLC; NO was determined by Griess agents; laminin and collagen IV were determined by enzyme-linked immunosorbent assay; the inducible NO synthase protein was determined by immunofluorescence staining and Western blot; and mesangial matrix expansion and MC proliferation in the renal cortex were observed by periodic acid-schiff staining and transmission electron microscopy, respectively.
The in vivo and in vitro studies indicated that the increased BH resulted in the overproduction of NO, ECM accumulation and the proliferation of MCs in early-stage DN.
Our results suggest that inhibiting excessive BH may be a potential approach to prevent glomerulosclerosis in early-stage DN.
一氧化氮（NO）在早期糖尿病肾病（DN）进展中起重要作用，已发现其可促进系膜细胞（MCs）中细胞外基质（ECM）积聚。作为NO生成的辅助因子，四氢生物蝶呤（BH），一种叶酸类似物，可能与MCs的ECM积聚和增殖有关。本研究旨在探讨BH对早期DN肾小球硬化的影响。
在体外培养系膜细胞的研究以及链脲佐菌素诱导的糖尿病大鼠体内研究中，通过高效液相色谱法测定BH水平；用格里斯试剂测定NO；用酶联免疫吸附测定法测定层粘连蛋白和IV型胶原；通过免疫荧光染色和蛋白质印迹法测定诱导型NO合酶蛋白；分别通过高碘酸-希夫染色和透射电子显微镜观察肾皮质中的系膜基质扩张和MC增殖。
体内和体外研究表明，BH增加导致早期DN中NO过量产生、ECM积聚和MC增殖。
我们的结果表明，抑制过量的BH可能是预防早期DN肾小球硬化的一种潜在方法。
