Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal, Karnataka, India.
Pharm Biol. 2010 Oct;48(10):1137-48. doi: 10.3109/13880200903527736.
High fat diet (HFD) and low-dose streptozotocin (STZ) is an ideal model for type 2 diabetes mellitus (T2DM) that would closely reflect the natural history and metabolic characteristics of human T2DM and is also suitable for pharmacological screening.
The present study was designed to investigate the effect of the water extract (DVW) and the polar fraction of ethanol extract (DVE-4) of Dodonaea viscosa (L). Jacq. (Sapindaceae) on biochemical parameters in type 2 diabetes induced by a standardized HFD and low dose streptozotocin (25 mg/kg) in rats. Further, to elucidate the mode of action we evaluated its effects on a battery of targets involved in glucose homeostasis (in vitro studies).
Different doses of DVW and DVE-4 were administered once daily for two weeks to HFD + STZ diabetic rats. Quantification of biomarker quercetin was done using HPLC.
Both DVW and DVE-4 dose-dependently reduced blood glucose, serum insulin, homeostatic model assessment (HOMA), lipid profiles, and significantly improved glucose tolerance and HDL-c levels. In addition, the extract and fraction also decreased oxidative stress by improving endogenous antioxidants. In different, bioassays, DVW and DVE-4 showed inhibition of PTP-1B and at a concentration of 10 μg/mL showed 60 and 54.2% binding to PPARγ, respectively. Both extract/fraction exhibited stimulation of glucose uptake by skeletal muscles.
Taken together, these results suggest that DVW and DVE-4 inhibits HFD + STZ-induced insulin resistance, lipid abnormalities and oxidative stress indicating that these effects may be mediated by interacting with multiple targets operating in diabetes mellitus.
高脂肪饮食(HFD)和低剂量链脲佐菌素(STZ)是 2 型糖尿病(T2DM)的理想模型,它能非常贴近地反映人类 T2DM 的自然病史和代谢特征,也适合药物筛选。
本研究旨在探讨醉茄(Dodonaea viscosa (L.) Jacq.)水提取物(DVW)和极性部位的乙醇提取物(DVE-4)对标准化 HFD 和低剂量链脲佐菌素(25mg/kg)诱导的 2 型糖尿病大鼠生化参数的影响。此外,为了阐明其作用机制,我们评估了其对涉及葡萄糖稳态的一系列靶标的影响(体外研究)。
不同剂量的 DVW 和 DVE-4 每天给药一次,连续两周,用于 HFD+STZ 糖尿病大鼠。使用 HPLC 定量测定生物标志物槲皮素。
DVW 和 DVE-4 均呈剂量依赖性地降低血糖、血清胰岛素、稳态模型评估(HOMA)、血脂谱,并显著改善葡萄糖耐量和 HDL-c 水平。此外,提取物和馏分还通过改善内源性抗氧化剂来降低氧化应激。在不同的生物测定中,DVW 和 DVE-4 显示出对 PTP-1B 的抑制作用,在 10μg/mL 浓度下,对 PPARγ 的结合率分别为 60%和 54.2%。提取物/馏分均能刺激骨骼肌摄取葡萄糖。
综上所述,这些结果表明,DVW 和 DVE-4 抑制 HFD+STZ 诱导的胰岛素抵抗、脂质异常和氧化应激,表明这些作用可能是通过与多个作用于糖尿病的靶点相互作用介导的。