Plant extracts as treatment for diabetes mellitus
The herbal extract of Artemisia has been regarded to be anti-hyperglycaemic since olden times and is commonly used by diabetics in Libya. The present work was designed to evaluate, test and determine which fraction or component of the herb had the hypoglycaemic effects in normal and streptozotocin-induced diabetic rats. The plant extract was administered to the animals in their drinking water and body weight, food and fluid intake and urine volume were all monitored daily. Food and fluid intake and body weight gain in normal rats were not altered by treatment with the plant extract but there was a rise in the urine glucose in the first six rats but rats 7, 8 and 9 were not affected by treatment with plant. Urine volume was increased in all rats suggesting Artemisia judaica is a mild diuretic. The streptozotocin-induced diabetic rat model, used in this study, was associated with the characteristic diabetic symptoms of hyperphagia, hyperglycaemia, polydipsia, weight loss and urinary glucose excretion. When a crude aqueous extract of Artemisia was given in their drinking water, it had little effect on these symptoms after 10 days of treatment. Urine glucose was reduced in the last two days and ketones in the urine were abolished by this treatment. Diabetes mellitus is known to affect many and varied parameters in rat liver. Insulin, biguanides and sulphonylureas are known antidiabetic diabetic treatments. Artemisia judaica extract was tested for its effect on hepatic steroid metabolism and glycogen phosphorylase a activity in comparison with the above drugs. Clearly Artemisia does act as an insulin-mimetic in these assays by reversing all the effects produced by the administration of streptozotocin. In particular the changes in the enzyme activities of cytochrome P-450 (2E1, 2B and 2C) on androst-4-ene-3, 17-dione metabolism are all reversed by the administration of Artemisia extract to diabetic rats.