Gymnema Sylvestre as an antidiabetic is widely used in India for over 2000 years, and modern research has found other applications where its use has important properties in diseases such as: arthritis, anemia, osteoporosis, hypercholesterolemia, microbial infection and anti-inflammatory. It’s a climbing plant with stems 8-10 meters long, held in high esteem by the Ayurvedic medicine which uses it even for other diseases such as malaria and snake bites.
The plant extract is used in certain food supplements as it reduces body weight, cholesterol, triglycerides and is becoming very important as an aid in the maintenance of low-calorie diets.
Gymnema Sylvestre as diabetes cure
There are experimental animal studies and clinical studies on patients who attest the antidiabetic properties of the plant. Already in 1926, this was described and published in “Indian Medical Gazetin” from Gharpurey.
The mechanism of action is undertaken through the stimulation of insulin secretion (hypoglycemic hormone) from the pancreas, and inhibiting the absorption of glucose in the intestine resulting in lower blood glucose. Modern research has also highlighted an important action of gymnemic acid (an active ingredient of the plant) on the secretion of incretins. These hormones are very important, secreted in the gastrointestinal tract after a meal especially rich in carbohydrates, go to modulate insulin secretion helping to maintain the right levels of blood sugar. Another hypothesis, proposed by several parties, suggests that the plant exerts a direct action on pancreatic regeneration.
In an interesting clinical trial published in the “Journal Ethnopharmacological” in 1990, performed on patients with insulin-dependent (ie forced to insulin therapy daily) showed that administration of 400 mg/day of soluble Gymnema (corresponding to 8 gr. of dry leaves ) reduced the insulin needs of 50%. For the duration of the treatment Gymnema reduced fasting blood glucose by 35%, and reported glycated hemoglobin values slightly higher than baseline. The same cholesterol had returned to near normal levels. The authors suggested that the Gymnema had improved insulin production possibly because it has favored the regeneration of the pancreas.
None of these improvements occurred in patients treated with insulin alone.
It’s very instructive to report the results of the same research group obtained in non-insulin dependent patients and treated with oral hypoglycemic medications. The plant administered for 18-20 months as a supplement to traditional drugs, significantly reduced blood glucose and glycated hemoglobin so much that it could be reduced the amount of conventional drugs in 21 of the 22 patients enrolled. 5 of the 22 diabetic patients were able to discontinue drug therapy and maintained glycemic balance only with the extract of Gymnema.
In this clinical setting, where the pancreas still has a remaining capacity of production of the hormone, Gymnema promotes and increases the entry of glucose into the cells , sensitive to the action of insulin such as liver, muscle and kidney. Also in these organs, but especially in the liver, Gymnema increases the conversion of glucose into glycogen (a large molecule of deposit that can not get out of the cell) contributing, through this mechanism, the reduction of blood glucose. Otherwise, in non-insulin dependent diabetic and non-treated, the cells are less sensitive to insulin action and become less permeable to glucose, causing an increase of its concentration in the blood.
Even in a recent US study published in the “Newsletter for Professionals in Diabetes Care” in 2001, there were confirmations of the effectiveness of the plant: 65 patients treated for 90 days with two tablets once a day of 400 mg of Gymnema have seen reduced fasting blood glucose of 11%, the blood glucose after a meal of 13% and the glycated hemoglobin of 6.8%.
The latter value today is very important in the management of diabetes as it gives us information on average blood glucose for the last three months and it is seen that the higher its value (dangerous above 8%) the more frequent are the complications of the disease as nephropathy, neuropathy and especially retinopathy! So a complementation of the classical therapy with titrated and purified extracts of the plant only brings big benefits.
Cravings for sweets and weight loss.
The gurmarin (one of the active ingredients of gymnema) has the unique property to inhibit the sensation of sweet at the level of the taste buds of the tongue, reducing the desire of sugar and sweet foods thus countering obesity.
In a study published in “Physiology and Behavior” in 1983, a group of patients was treated with an oral solution gymnena based and another group with a solution of tea. It was seen that the participants who had taken the solution containing the Gymnema introduced in the following hours a quantity of sugars, lipids and proteins significantly below compared to the control group treated with tea.
Currently gymnemic acids are marketed as dietary supplements and in Japan there are teas made from Gymnema that are a great natural way to combat obesity, diabetes and promote weight loss.
Antiarthritic activity
The extract of the leaves of the plant has been shown to have remarkable anti-arthritic and anti-inflammatory properties. These properties have been demonstrated in experiments on albino rats which it was chemically induced inflammation in the paw. The extract of Gymnema has shown to reduce significantly the swelling and pain by inhibition of inflammatory cells and by blocking pro-inflammatory chemical mediators.
Antimicrobial activity
The antibiotic and bacterial activity of Gymnema leaf has been determined against numerous bacterial species all Gram +, for instance all bacteria sensitive to the famous, and often abused, erythromycin or clarithromycin antibiotics. These properties are described in a study published in the “International Journal of Pharmaceutical research and Development” in 2010.
Also dental caries, being an infection of the tooth caused by Gram + as Staphilococco mutans, responds well to the use of gymnena toothpastes.
There are toothpastes available in India and in other Eastern countries, as marketed products as “Gurmar Herbal toothpaste” that have good prospects in the treatment of caries.
Anti-inflammatory activity
We have already spoken of this property but it is worth reporting the significant and interesting results of a study of Diwan and coll. published in “Inflammopharmacology” 1995.
In a population of rats it was induced paw inflammation with the injection of carrageenan (this is the gelling of the pudding and pies in the food) and then were divided into two groups: one group was treated with aqueous extracts of Gymnema at doses of 300-500 mg/kg, and another group with a powerful anti-inflammatory no longer for sale for human use: phenylbutazone used as reference standard. Well it was found that the aqueous extract of Gymnema decreased the paw edema by 48.5% within 4 hours of administration, while the phenylbutazone has reduced the volume of edema of 57.6%.
If account is taken of the power and the toxicity of the drug with respect to the safety and maneuverability of the plant, the result is very remarkable.
Lipid-lowering activity
A very important factor that contributes to the formation of atherosclerosis (chronic inflammatory disease of the arteries of large and medium caliber) and related diseases, such as heart attack and stroke, is undoubtedly the high concentration of lipids and cholesterol.
In a study published in “International Journal of Pharmacology” in 2010, the effects of the administration of aqueous extracts of Gymnema were studied in hyperlipidemic mice because of a diet rich in cholesterol and administered for seven days. The results were clear: Gymnema obtained a lowering of cholesterol and triglyceride levels comparable to that obtained from atorvastatin, powerful and important modern drug for the control of plasma lipids.
In another study published in “Molecolar Cellular Biochemistry” in 2007 and conducted on animals, it emerges a very important discovery: the administration with plant extracts promoted weight loss also for its ability to reduce the high concentration of lipids without procure bounce symptoms after its suspension. There isn’t the dreaded yo-yo effect that is the re-acquisition of the weight and of the high cholesterol values after discontinuation of therapy.
Other activities
The aqueous extract of the plant has been shown, in vitro, to possess considerable immunostimulant properties.
At hepatic level, it was studied the hepatoprotective ability against toxicity by galactosamine. Liver cells showed a significant recovery of biochemical parameters if treated with extracts of Gymnema.
The presence of flavonoids is probably responsible for the considerable activity on wound healing demonstrated by the plant.
In traditional medicine , the flowers and the bark are used in diseases related to phlegm, the root bark is useful as an expectorant and pain reliever, the juice of the root is useful in the treatment of snake bites.
Modern research with its animal and clinics testing and is only at the beginning of the knowledge of the many properties of this very important plant.
Doctor Claudio Sandri
Translated by Ms Jeanne Marie Arcaini