Home Herbal Monograph Gymnema
History

This plant was called Meshashringi or "ram's horn" in Sanskrit. Its use in snake bite as a remedy was well known to the natives of the Konkan in India and the natives of Southern India. A curious circumstance connected with this plant was first noticed by Mr. Edgeworth, namely, that if chewed it destroys the power of the tongue to appreciate the taste of sugar and all saccharine substances. This property of the leaves has been tested in 1887, carefully by Mr. D. Hooper.

Habitat

It is found in the Deccan Peninsula, extending to parts of northern and western India. It is occasionally cultivated as a medicinal plant.

Morphology Description (Habit)

G.sylvestre is a large, more or less pubescent, woody climber. The leaves are opposite, elliptic or ovate; the flowers are small, yellow and in umbellate cymes; the follicles are terete, lanceolate and up to 3 inches in length.

Principal Constituents

Aqueous extract of the leaves contains antisweet principles gymnema saponins I-IV and gymnemic acids I-IX1.

Pharmacology

Water-soluble extracts were tested in streptozotocin treated rats. Blood pressure and glucose level return to normal levels after 60 days of oral administration. Also in pancreas islet number and b-cell number were doubled. This herbal therapy appears to bring about blood glucose homeostasis through increased serum insulin levels provided by repair presentation of the endocrine pancreas2().The Alcoholic extract of the leaves of G.sylvestre was studied to know the hepatoprotective action in a dose of 300mg/kg against CCl4induced damage. The extracts were found to be effective in preventing damage, which was evidenced by morphological, biochemical and functional parameters3.

Clinical Studies

GS4, an extract from the leaves of G.sylvestre, was administered (400mg/day) for 18-20 months as a supplement to the conventional oral drugs. During GS4 supplementation, the patients showed a significant reduction in blood glucose, glycosylated hemoglobin and glycosylated plasma proteins, and conventional drug dosage could be decreased. Five of the 22 type 2 diabetic patients were able to discontinue their conventional drug and maintain their blood glucose homeostasis with GS4 alone4.


Toxicology

Little is known about the long-term safety of the plant, but it generally has not been associated with human toxicity5.

Indications

Gymnemic acid has anti-diabetic property. It has an inhibitory effect on plasma glucose and serum insulin in man. The plant is stomachic, stimulant, laxative and diuretic. The leaves of the plant, when chewed, possess the remarkable property of paralysing, for a few hours, the sense of taste for sweet and bitter substances; the taste for acid foods is not affected while the taste for salty foods is very slightly, if at all, influenced.

References
  1. Chem. Abst. 1991, 114,58873, 03562; 1989, 110,191267; Yoshikawa et. al., Phytochemistry, 1992, 31, 237.
  2. Shanmugasundaram, Journal of Ethnopharmacology, V30 (3), 1990, pp.265-279.
  3. Rana, Fitoterapia, v.63 (1): p.60-62, 1992.
  4. Baskaran, K. et. al., J. of Ethnopharmacol., 1990, v., 30(3), 295-305.
  5. Liberti, L., Lawrence Review of Natural Products, August 1993, 1.