Diabetic nephropathy (DN) is one of the serious complications in diabetes. Cyanidin-3-glucoside (C3G) from black rice was reported to have hypoglycemic effects and an anti-osteoporosis effect in diabetic rats. Whether it has preventive effects on DN has not been reported. In this study, we established a rat model of DN, and C3G at two doses (10 and 20 mg kg^–1 day^–1) were administered to see its anti-DN effect. A total of 8 weeks of C3G supplementation decreased blood glucose and serum insulin, improved the renal function, and relieved renal glomerular sclerosis and interstitial fibrosis of DN rats. Also, the kidneys of DN rats had improved the oxidative defense system. Pro-inflammatory mediators were markedly reduced in serum and kidneys of the C3G-treated groups. Transforming growth factor β1 (TGF-β1), phosphor-Smad2, and phosphor-Smad3 protein expression levels were significantly decreased in the kidney of the C3G-treated group, whereas the Smad7 expression level was upregulated by C3G. Our results indicate that C3G can ameliorate DN via antioxidative stress and anti-inflammation and regulate the TGF-β1/Smad2/3 pathway. Our results suggest that C3G from black rice might be used as a renal-protective nutrient in DN.

中文翻译：

---

黑米中的Cyanidin-3-glucoside通过降低血糖，抑制氧化应激和炎症以及调节转化生长因子β1/ Smad的表达来减轻糖尿病性肾病。

糖尿病肾病（DN）是糖尿病的严重并发症之一。据报道，来自黑米的Cyanidin-3-glucoside（C3G）在糖尿病大鼠中具有降糖作用和抗骨质疏松作用。它是否对DN有预防作用尚未见报道。在这项研究中，我们建立了DN和C3G两种剂量（10和20 mg kg ^–1天^–1）的大鼠模型。），以观察其抗DN的作用。补充C3G总共8周降低了DN大鼠的血糖和血清胰岛素，改善了肾功能，并缓解了肾小球硬化和间质纤维化。另外，DN大鼠的肾脏改善了氧化防御系统。C3G治疗组的血清和肾脏中促炎性介质明显减少。在C3G治疗组的肾脏中，转化生长因子β1（TGF-β1），磷光体Smad2和磷光体Smad3蛋白表达水平显着降低，而C3G上调了Smad7表达水平。我们的结果表明，C3G可以通过抗氧化应激和抗炎作用改善DN，并调节TGF-β1/ Smad2 / 3途径。