Antidiabetic Effect of Chinese yam (Dioscorea opposita Thunb.) in High‐Fat Diet/Streptozotocin‐Induced Diabetic Rats

Abstract

This study aims to assess the effect of different doses of Chinese yam (CY) on a high‐fat diet (HFD) and a streptozotocin‐induced diabetic rat model, using resistant starch (RS) as a positive control. Rats in the normal control and diabetes model (DM) groups are fed the standard diet and HFD, respectively. The RS and CY‐intervention groups are fed with a special HFD, in which starch, maltodextrin, and sucrose in the HFD are replaced completely with RS or CY powder in different proportions: 33.33% (1/3), 66.67% (2/3), and 100% respectively. The results show that CY powder can decrease serum levels of total triglycerides, total cholesterol, low‐density lipoprotein cholesterol, fasting blood glucose, and glycated hemoglobin, lower abdominal fat weight and abdominal fat index, increase levels of insulin and hepatic glycogen, and improve glucose tolerance and insulin sensitivity in diabetic rats. In addition, CY reduces oxidative stress and inflammation and reduces spleen weight and spleen index in diabetic rats. Notably, CY shows higher efficacy than RS in glucose tolerance and serum insulin and nitric oxide levels. This study suggests that CY powder may replace RS as a functional food in diabetic diets.

A Comparative Analysis between Whole Chinese Yam and Peeled Chinese Yam: Their Hypolipidemic Effects via Modulation of Gut Microbiome in High-Fat Diet-Fed Mice

“…According to the ancient Chinese pharmacopoeia "Compendium of Materia Medica", yam was recorded to be conducive to nourishing the spleen and stomach, strengthening immunity, and delaying ageing. Furthermore, emerging evidence has demonstrated that the bioactive ingredients of yam possess many other potential health benefits such as antioxidant [14], anti-inflammatory [15], antitumor [16], anti-diabetic [17], and anti-obesity and hypolipidemic [18] activities. However, the research lipid-lowering activity is frequently limited to studies on single components or extracts of yam [19,20], and it is unclear whether yam maintains similar effects when consumed as a whole food.…”

Preparation, structure characterization, and in vitro bioactivity of yam starch-polyphenol complex

“…[4,5] The native YS mainly falls into the RS2 category, possessing inherent compactness that imparts digestive resistance but becomes susceptible to digestion upon cooking. [6] To retain intrinsic antidigestive attributes of YS, modifications are imperative. Recent studies have identified the emergence of a novel RS variant, classified as RS5, which involves the introduction of fatty acids or polyphenols into the hydrophobic cavity of amylose.…”