A novel Gymnema sylvestre extract stimulates insulin secretion from human islets in vivo and in vitro

Phytother Res. 2010 Sep;24(9):1370-6. doi: 10.1002/ptr.3125.


Many plant-based products have been suggested as potential antidiabetic agents, but few have been shown to be effective in treating the symptoms of Type 2 diabetes mellitus (T2DM) in human studies, and little is known of their mechanisms of action. Extracts of Gymnema sylvestre (GS) have been used for the treatment of T2DM in India for centuries. The effects of a novel high molecular weight GS extract, Om Santal Adivasi, (OSA(R)) on plasma insulin, C-peptide and glucose in a small cohort of patients with T2DM are reported here. Oral administration of OSA(R) (1 g/day, 60 days) induced significant increases in circulating insulin and C-peptide, which were associated with significant reductions in fasting and post-prandial blood glucose. In vitro measurements using isolated human islets of Langerhans demonstrated direct stimulatory effects of OSA(R) on insulin secretion from human ß-cells, consistent with an in vivo mode of action through enhancing insulin secretion. These in vivo and in vitro observations suggest that OSA(R) may provide a potential alternative therapy for the hyperglycemia associated with T2DM.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Blood Glucose / metabolism*
  • C-Reactive Protein / metabolism
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Fasting
  • Female
  • Gymnema sylvestre*
  • Humans
  • Hypoglycemic Agents / pharmacology
  • Hypoglycemic Agents / therapeutic use*
  • In Vitro Techniques
  • Insulin / blood
  • Insulin / metabolism*
  • Insulin Secretion
  • Insulin-Secreting Cells / drug effects*
  • Insulin-Secreting Cells / metabolism
  • Male
  • Middle Aged
  • Molecular Weight
  • Phytotherapy
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Plant Extracts / therapeutic use*
  • Plant Leaves
  • Postprandial Period


  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin
  • Plant Extracts
  • C-Reactive Protein