Biol. Pharm. Bull. 28(6) 978—983 (2005)

insulin dysfunction in conjugation with gross abnormalities in glucose homeostasis and lipid metabolism, which has affecting several millions of population all over the world. The individual with diabetes has a 25-fold increase in the risk of blindness, a 20-fold increase in the risk of renal failure, a 20-fold increase in the risk of amputation as a result of gangrene and a 2 to 6 fold increased risk of coronary heart disease and ischaemic brain damage. There is considerable evidence on the role of free radicals in the etiology of diabetes and altered antioxidant defenses in diabetes. Oxidative stress has been reported to play an important role in diabetes mellitus right from its genesis to the development of microvascular complications. Generation of free radicals by hyperglycemia is related to glucose auto-oxidation. Glucose auto-oxidation has been linked to non-enzymatic glycosylation and glycosylated proteins have been shown to be a source of free radicals. Prior to 1950’s control of diabetes was based entirely on insulin therapy. Unfortunately, some patients developed complications and thus need for some other therapy was realized. Presently control of diabetes mellitus relies on many chemicals and plant extracts. More than 400 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. There was a gap in proper understanding of medicinal plants for mankind in past because traditional medicines generally lacked scientific explanations. Many plant extracts and plant products have been shown to reduce oxidative stress significantly, which may be an important property of plant medicines associated with the treatment of several ill fated diseases including diabetes. It has been found that compounds in their natural formulations are more active than their isolated form. Among these Momordica charantia is a good example of ignorant folk medicine out stripping scientific understandings in the therapeutic applications is selected for this study. Consumption of bitter gourd (Momordica charantia) by diabetic patients is a common practice in India, with the belief that it has a useful hypoglycemic potential. Momordica charantia (MC) LINN, commonly referred to as bittergourd or karela, belongs to the Curcurbitaceae family. It is a climbing plant, cultivated throughout Southern Asia. Its fruits are very cheap and available throughout the year. Immature fruits are used to prepare different dishes for human consumption, while highly matured fruits are considered as not worthy for consumption. There are two varieties of this vegetable based on size and shape. The large variety is long, oblong and pale green in color. The other one is small, little oval and dark green in color. The yield of small variety per plant is much less when compared to large ones; as a result the cost of the small variety is almost thrice when compared to the larger ones. Both the types are bitter in taste. The pulp is blood red or scarlet after dehiscence. The seeds are dappled, flat, thick notched margin, red aril in morphology and it is white color in raw fruits and become red when they are ripe. Different parts of these plants have been used in the Indian system of medicine for a number of ailments besides diabetes. Our previous experimental results were highly encouraging as they revealed that blood glucose level was significantly lowered after oral administration of aqueous extract of Momordica charantia seeds in glucose load condition and in streptozotocin induced diabetes. In view of the above considerations, the present study was designed to examine the effect of an aqueous extract from the seeds of Momordica charantia on oxidative stress in plasma and pancreas of diabetic rats induced by streptozotocin, and their efficacy was compared with glibenclamide, a standard hypoglycemic drug.