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Anti-diabetic Effect of Gynostemma Pentaphyllum Tea in Type 2 Diabetic Patients

This study has been completed.
Karolinska Institutet
Swedish International Development Cooperation Agency (SIDA)
Information provided by:
Hanoi Medical University Identifier:
First received: November 5, 2008
Last updated: December 3, 2010
Last verified: November 2008
The aim of the present study was to investigate the long-term effects on blood glucose concentrations and possible adverse effects of an extract of Gynostemma pentaphyllum (GP). This is a plant growing in the mountain regions of Northern Vietnam and previously being used in traditional medicine. The GP extract, or placebo, was randomized to newly diagnosed patients with type 2 diabetes and administered as a "tea", 3 g two times daily during 12 weeks. All patients received instructions regarding diet and physical exercise. Oral glucose tolerance tests were performed at baseline and then every 4 weeks, and blood tests were taken with the purpose to monitor lipids, kidney and liver function, body weight and blood pressure.

Condition Intervention Phase
Type 2 Diabetes
Dietary Supplement: Gynostemma pentaphyllum tea
Dietary Supplement: Placebo tea
Phase 1
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Investigator)
Primary Purpose: Treatment
Official Title: Anti-diabetic Effect of Gynostemma Pentaphyllum Tea in Type 2 Diabetic Patients

Resource links provided by NLM:

Further study details as provided by Hanoi Medical University:

Primary Outcome Measures:
  • Fasting plasma glucose [ Time Frame: 12 weeks ]
  • HbA1c (glycosylated hemoglobin) [ Time Frame: 12 weeks ]

Secondary Outcome Measures:
  • Liver enzymes (ALT, AST) [ Time Frame: 12 weeks ]
  • Kidney function (S-creatinine, S-BUN) [ Time Frame: 12 weeks ]
  • Plasma lipids (TG, Cholesterol, HDL-, LDL-) [ Time Frame: 12 weeks ]
  • Blood pressure [ Time Frame: 12 weeks ]
  • Body weight (BMI, hip-waist ratio) [ Time Frame: 12 weeks ]

Enrollment: 24
Study Start Date: February 2007
Study Completion Date: December 2007
Primary Completion Date: September 2007 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Gynostemma pentaphyllum tea Dietary Supplement: Gynostemma pentaphyllum tea
3 grams twice daily, orally
Placebo Comparator: Placebo tea Dietary Supplement: Placebo tea
3 grams twice daily, orally

Detailed Description:

In Vietnam, herbal extracts have been used as a long-standing tradition to treat diabetic patients, but effects of these extracts have not been studied adequately. Based on previous results in experimental animals, we have selected the plant Gynostemma pentaphyllum (GP), which grows in the mountain region of Northern Vietnam. GP extract had a hypoglycemic effect on mice and rats, and was shown to contain a substance, phanoside, which stimulates insulin secretion. In addition, GP has been shown to reduce both hyperglycemia and hyperlipidemia in diabetic Zucker fatty rats.

The present study aimed at investigate effects of GP extract, administered as a "tea", and compared with placebo in a randomized, double-blind trial in drug-naive patients with newly diagnosed type 2 diabetes. All patients also received instructions about diet and physical exercise. In addition to monitoring effects on plasma glucose regulation, we also studied possible effects on plasma lipids, kidney and liver function as well as body weight and blood pressure.


Ages Eligible for Study:   40 Years to 70 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Newly diagnosed, drug-naive patients with type 2 diabetes
  • Fasting plasma glucose (FPG) 7.0-14.0 mmol/l
  • HbA1c > 6%

Exclusion Criteria:

  • Type 1 diabetes
  • Liver failure
  • Kidney Failure
  Contacts and Locations
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Please refer to this study by its identifier: NCT00786500

National Institute of Gerontology, HMU
Hanoi, Vietnam
Sponsors and Collaborators
Hanoi Medical University
Karolinska Institutet
Swedish International Development Cooperation Agency (SIDA)
Study Director: Claes Goran Ostenson, MD, PhD Karolinska Institutet
  More Information

Additional Information:
Publications: Identifier: NCT00786500     History of Changes
Other Study ID Numbers: Diabetes II
Study 1
Study First Received: November 5, 2008
Last Updated: December 3, 2010

Keywords provided by Hanoi Medical University:
Herbal medicine
Type 2 diabetes
Insulin sensitivity
Insulin secretion

Additional relevant MeSH terms:
Diabetes Mellitus, Type 2
Diabetes Mellitus
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Hypoglycemic Agents
Physiological Effects of Drugs processed this record on May 25, 2017