Nutraceutical Herbs and Insulin Resistance
Robert E.C. Wildman, Richard S. Bruno in Handbook of Nutraceuticals and Functional Foods, 2019
Gymnema sylvestre helps to promote weight loss through its ability to reduce the desire for sweets, and also controls blood glucose levels. Chewing the leaves, rinsing the mouth with watery extracts, or applying an extract topically on the tongue selectively inhibit the feeling of sweetness. Some studies have suggested that gymnemic acid binds to the receptor located on the taste buds of the tongue and prevents their activation by the sugar molecules. Gymnema sylvestre also suppresses the absorption of sugars, presumably by blocking the sucrose receptors through one of its component, the peptide gurmarin.42,43 It would seem, moreover, that not only does this plant block the receptors at the level of the mouth, it also acts, with the same inhibitory activity, on the sodium-dependent glucose transporters expressed at high concentrations on the intestinal cell brush.44
The Rational Use of Dietary Supplements, Nutraceuticals, and Functional Foods for the Diabetic and Prediabetic Patient
Jeffrey I. Mechanick, Elise M. Brett in Nutritional Strategies for the Diabetic & Prediabetic Patient, 2006
Gymnema sylvestre, or gurmar, is another Indian remedy that has been referred to as a “sugar blocker” in the U.S. market. In an uncontrolled study of 22 T2DM patients, administration of 400 mg of Gymnema sylvestre extract (GS4) for 18–20 months improved glycemic control (decreased fasting glucose, from 174 mg/dL to 124 mg/dL, and A1C, from 11.9% to 8.48%), lipid status (decreased total cholesterol from 260 mg/dL to 231 mg/dL) and was associated with reductions in oral hypoglycemic medication dosing [79]. Five of 22 patients in this study needed to discontinue oral hypoglycemics to avoid hypoglycemia (evidence level 3) [79]. In another uncontrolled study of 27 patients with T1DM by the same research group in Madras, India, the same GS4 extract amount was associated with decreased insulin requirements (25% after 6–8 months and 50% after 26–30 months), short-term improvements in fasting glucose (232 mg/dL to 177 mg/dL), A1C (12.8% to 9.5%), and increased endogenous insulin production via increased β-cell function (evidence level 3) [80]. These beneficial effects of GS4 are thought to be mediated via improved β-cell permeability and insulin-dependent glucose utilization pathways [76]. There were no significant adverse effects of Gymnema sylvestre extract in the above clinical studies (grade C).
Lessons to Be Learnt from Ayurveda
D. Suresh Kumar in Ayurveda in the New Millennium, 2020
The herb Gymnema sylvestre has gained importance, as chewing its leaves can reduce the sensation of sweet taste due to which it is known as gurmār or “sugar-destroyer” (Power 1904). An extract of Gymnema sylvestre leaves (400 mg/day) was administered to 22 type 2 diabetic patients for 18–20 months, in addition to conventional oral drugs. The patients showed a significant decrease in blood glucose, glycosylated hemoglobin and glycosylated plasma proteins. The conventional drugs could also be withdrawn. Five patients on the extract treatment were able to maintain their glucose homeostasis and discontinued the conventional drugs, indicating regeneration of beta cells in them, as evidenced by increased insulin levels (Baskaran et al. 1990).
Radio-protective efficacy of Gymnema sylvestre on Pangasius sutchi against gamma (60Co) irradiation
Published in International Journal of Radiation Biology, 2022
Pamela Sinha, Kantha Devi Arunachalam, Santhosh Kumar Nagarajan, Thirumurthy Madhavan, Arumugam R. Jayakumar, Mohamed Saiyad Musthafa
All chemicals and reagents (analytical grade) used for cell culture and assays were purchased from Sigma Aldrich, Bangalore, India. Gymnemagenin the bioactive compound from Natural remedies Pvt, Ltd. Bengaluru, Karnataka, India. The Gymnema sylvestre leaves were obtained from the Herbal Garden, Tamil University, Thanjavur, Tamil Nadu.
Related Knowledge Centers
- Ayurveda
- Gymnemic Acid
- Flavonols
- Gurmarin