Makino
|
Hypoglycemic Activity of Extract from Gynostemma pentaphyllum Makino
|
| Author |
Miss Warawan Poomecome
|
| M.S. |
Pharmacology |
| Examining Committee |
Assoc. Prof. Dr. Duangta Kanjanapothi
|
Chairman |
|
Assoc. Prof. Dr. Ampai Panthong
|
Member |
|
Asst. Prof. Dr. Tawat Taesotikul
|
Member |
|
Assoc. Prof. Dr. Nirush Lertprasertsuke
|
Member |
Traditional plant treatments for diabetes mellitus have been recorded but only a small number of these have received scientific and medical evaluation to assess their efficacy.
Gynostemma pentaphyllum Makino., (family Cucurbitaceae), an indigenous plant of Southeast Asia has been used in folk medicines to alleviate symptoms and diseases including cough, migraine, insomnia, hypertension and diabetes mellitus. In the present study the ethanolic extract of G. pentaphyllum was tested for hypoglycemic effect in various experimental models, which included blood glucose of normal as well as alloxan-induced diabetic rats, and glucose tolerance test (administration of G. pentaphyllum before a glucose load and simultaneous administration of G. pentaphyllum with a glucose load). Prolonged administration (4 weeks) of the ethanolic extract of G. pentaphyllum was performed in normal as well as streptozotocin-induced diabetic rats to investigate hypoglycemic and other effects including effects on blood cholesterol, organ and body weights. Hypoglycemic activity of G. pentaphyllum has been found in experiments determining effect of
G. pentaphyllum on blood glucose of normoglycemic rat, and glucose tolerance test. However, the hypoglycemic activity of G. pentaphyllum was not apparent in alloxan-induced diabetic rats. The findings indicate that the hypoglycemic activity is due to an ability to stimulate insulin release from the pancreas but not insulin like activity. Results from the glucose tolerance test of which G. pentaphyllum was administered simultaneously with a glucose load suggest that G. pentaphyllum may also exhibit an inhibitory effect on glucose absorption from the gastrointestinal tract. In the prolonged treatment, G. pentaphyllum showed a hypoglycemic activity in normal as well as streptozotocin-induced diabetic rats. The hypoglycemic activity in streptozotocin-induced diabetic rats is probably due to G. pentaphyllum causes a stimulation of surviving pancreatic beta cells to release insulin. In normal rats, the body weight of G. pentaphyllum treated group was
gradually increased, but the increase was less than that of the control group. In streptozotocin-induced diabetic rats, G. pentaphyllum induced weight gain and increased weights of liver and kidneys. Additionally, the cholesterol lowering activity of G. pentaphyllum was detected in both normal and streptozotocin-induced diabetic rats.