Jiao Yukun, Zhang Mengliu, Wang Shumei, Yan Chunyan
School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, PR China; Key Laboratory of Digital Quality Evaluation of Chinese Materia Medica of State Administration of TCM, PR China; Engineering & Technology Research Center for Chinese Materia Medica Quality of the Universities of Guangdong Province, PR China.
School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, PR China.
Int J Biol Macromol. 2017 Aug;101:543-552. doi: 10.1016/j.ijbiomac.2017.03.130. Epub 2017 Mar 25.
The objectives of this study were to evaluate the anti-diabetic and anti-hyperlipidemic effects and relative mechanisms of guava polysaccharides (GPs) in rats with type 2 diabetic mellitus (T2DM). The chemical characterization and monosaccharide compositions of GPs, named as GP-1, GP-2, GP-3, and GP-4, were determined by PMP-HPLC and FT-IR. The results revealed that all GPs had the typical saccharide absorptions, and all were heteropolysaccharides. In addition, GPs efficiently decreased levels of fasting blood glucose, glucosylated serum protein, serum insulin, homeostasis model assessment of insulin resistance, total cholesterol, triglyceride and serum alanine transaminase, improved oral glucose tolerance, and increased insulin sensitivity in rats with T2DM. Histopathological observations suggested that GP-1, GP-3, and GP-4 could alleviate injury in pancreatic islet cells, and Western blot analysis showed that these GPs upregulated gene expression of the insulin receptor, insulin receptor substrate 2, Akt, and glucose transporter type 4. Taken together, these data suggest that GPs may be beneficial in treating T2DM and reducing the risk of hyperlipidemia, vascular disease, and cirrhosis via the PI3K/Akt signaling pathway.
本研究的目的是评估番石榴多糖（GPs）对2型糖尿病（T2DM）大鼠的抗糖尿病和抗高脂血症作用及其相关机制。采用PMP-HPLC和FT-IR法测定了命名为GP-1、GP-2、GP-3和GP-4的GPs的化学特征和单糖组成。结果显示，所有GPs均具有典型的糖类吸收峰，且均为杂多糖。此外，GPs能有效降低T2DM大鼠的空腹血糖、糖化血清蛋白、血清胰岛素、胰岛素抵抗稳态模型评估、总胆固醇、甘油三酯和血清丙氨酸转氨酶水平，改善口服葡萄糖耐量，并提高胰岛素敏感性。组织病理学观察表明，GP-1、GP-3和GP-4可减轻胰岛细胞损伤，蛋白质免疫印迹分析显示，这些GPs上调了胰岛素受体、胰岛素受体底物2、Akt和4型葡萄糖转运蛋白的基因表达。综上所述，这些数据表明，GPs可能通过PI3K/Akt信号通路对治疗T2DM以及降低高脂血症、血管疾病和肝硬化的风险有益。
