The effect of Aqueous, Ethanolic extracts of Rheum ribeson insulin sensitivity, inflammation, oxidative stress in patients with type 2 diabetes mellitus: A Randomized, Double-Blind, Placebo-Controlled Trial

Type 2 diabetes mellitus, one of the most common chronic metabolic disorders, occurs when the body is unable to utilize insulin effectively. Hyperglycemia, one of the most common characteristics of diabetes, is related to the development of several diabetic adverse effects, which lead to an elevation in oxidative stress and inflammation responses. Among the current therapeutic options, such as hypoglycemic drugs and insulin therapy, which have limitations, there has been much attention given to the use of traditional medicinal plant that modulate hyperglycemia, inflammation, improve oxidative stress, and prevent diabetes-induced complications. Therefore, the aim of the current study is to investigate whether the consumption of aqueous and ethanolic Rheum extractions improve insulin sensitivity, inflammation and oxidative status in subjects with T2DM. Sixty patients with T2DM (male and female) were recruited in this double-blind, randomized and controlled clinical trial from the Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran. The participants were randomly allocated into three groups aqueous extract (n = 20), ethanolic extract (n = 20) and control (n = 20) who were given three Rheum ribes capsules daily for 6 weeks. A significant elevation in the quantitative insulin-sensitivity check index (QUICKI) was observed at the end of study in the aqueous extracts (P = 0.03) and also ethanolic extracts (P = 0.01) of Rheum extract groups compared to initial values. At the end of study, there was also a significant reduction in levels of malondialdehyde (MDA) in ethanolic extracts (P = 0.002) compared to initial values; however, intervention with aqueous extracts had no effect on malondialdehyde. There was also a significant reduction of high sensitivity C-reactive protein in ethanolic extracts (P = 0.001) and aqueous extracts (P = 0.001) groups at the end of study compared to initial values. At the end of the study, there were significant differences in the insulin, ethanolic extract group compared to control group. It appears that the ethanolic extract is more effective than the aqueous extract of Rheum ribes in diabetic patients. Rheum ribes intake may have favorable effects on insulin sensitivity, malondialdehyde and high sensitivity C-reactive protein in diabetic patients.