Dr. Ron's Research Review – February 17, 2016
This week's research review focuses on Gynostemma for diabetes.
Gynostemma (Jiaogulan) is an adaptogenic herb from the cucmber and melon family known as "southern ginseng" and the "miracle green."
A study examined the effects of gynostemma pentaphyllum (6 g daily) together with gliclazide (a sulfonylurea drug, 30 mg daily) in 25 drug-naïve type 2 diabetic patients. After 4-week gliclazide treatment, fasting plasma glucose (FPG) and HbA(1C) decreased significantly (P < 0.001). FPG was further reduced after add-on therapy with 2.9 ± 1.7 and 0.9 ± 0.6 mmol/L in the gynostemma and placebo groups, respectively (P < 0.001). Therapy with gynostemma extract also reduced 30- and 120-minute oral glucose tolerance test postload values. HbA(1C) levels decreased approximately 2% units in the gynostemma group compared to 0.7% unit in the placebo group (P < 0.001). (Huyen et al., 2012)
Drug-naïve type 2 diabetic patients received gynostemma or placebo tea 6 g daily for four weeks and vice versa with a 2-week wash-out period. At the end of each period, a somatostatin-insulin-glucose infusion test (SIGIT) was performed to evaluate the insulin sensitivity. FPG and steady-state plasma glucose (SIGIT mean) were lower after gynostemma treatment compared to placebo treatment (P < 0.001). The levels of FPG in the control group were slightly reduced to 0.2 ± 1.5 versus 1.9 ± 1.0 mmol/L in gynostemma group (P < 0.001), and the effect on FPG was reversed after exchanging treatments. The glycometabolic improvements were achieved without any major change of circulating insulin levels. (Huyen et al., 2013)
Antidiabetic Effects of Add-On Gynostemma pentaphyllum Extract Therapy with Sulfonylureas in Type 2 Diabetic Patients.
(Huyen et al., 2012) Download
Aims. To investigate the antidiabetic effect of the traditional Vietnamese herb Gynostemma pentaphyllum (GP) together with sulfonylurea (SU) in 25 drug-naïve type 2 diabetic patients. Methods. After 4-week treatment with gliclazide (SU), 30 mg daily, all patients were randomly assigned into 2 groups to add on GP extract or placebo extract, 6 g daily, during eight weeks. Results. After 4-week SU treatment, fasting plasma glucose (FPG) and HbA(1C) decreased significantly (P < 0.001). FPG was further reduced after add-on therapy with 2.9 ± 1.7 and 0.9 ± 0.6 mmol/L in the GP and placebo groups, respectively (P < 0.001). Therapy with GP extract also reduced 30- and 120-minute oral glucose tolerance test postload values. HbA(1C) levels decreased approximately 2% units in the GP group compared to 0.7% unit in the placebo group (P < 0.001). Conclusion. GP extract in addition to SU offers an alternative to addition of other oral medication to treat type 2 diabetic patients.
Gynostemma pentaphyllum Tea Improves Insulin Sensitivity in Type 2 Diabetic Patients.
Aims. To evaluate the effect of the traditional Vietnamese herb Gynostemma pentaphyllum tea on insulin sensitivity in drug-naïve type 2 diabetic patients. Methods. Patients received GP or placebo tea 6 g daily for four weeks and vice versa with a 2-week wash-out period. At the end of each period, a somatostatin-insulin-glucose infusion test (SIGIT) was performed to evaluate the insulin sensitivity. Fasting plasma glucose (FPG), HbA(1C), and oral glucose tolerance tests and insulin levels were measured before, during, and after the treatment. Results. FPG and steady-state plasma glucose (SIGIT mean) were lower after GP treatment compared to placebo treatment (P < 0.001). The levels of FPG in the control group were slightly reduced to 0.2 ± 1.5 versus 1.9 ± 1.0 mmol/L in GP group (P < 0.001), and the effect on FPG was reversed after exchanging treatments. The glycometabolic improvements were achieved without any major change of circulating insulin levels. There were no changes in lipids, body measurements, blood pressure, and no reported hypoglycemias or acute adverse effects regarding kidney and liver parameters. Conclusion. The results of this study suggested that the GP tea exerted antidiabetic effect by improving insulin sensitivity.
Huyen, VT, et al. (2012), 'Antidiabetic Effects of Add-On Gynostemma pentaphyllum Extract Therapy with Sulfonylureas in Type 2 Diabetic Patients.', Evid Based Complement Alternat Med, 2012 452313. PubMed: 23125867
Huyen, VT, et al. (2013), 'Gynostemma pentaphyllum Tea Improves Insulin Sensitivity in Type 2 Diabetic Patients.', J Nutr Metab, 2013 765383. PubMed: 23431428