Biol. Pharm. Bull. 27(5) 694—698 (2004)

morbidity and mortality in the world. About 2.5—3% of the world’s population suffers from this disease, a proportion which, in some countries, can reach 7% or more. Hyperglycemia leads to metabolic disorders and various complications. There is increasing evidence indicating that enhanced production of free radicals may be an important contributing factor in the complications seen in diabetes. Species increased in diabetes, especially in uncontrolled diabetes, can lead to the autooxidation of glycosylated proteins, activation of the sorbitol pathway, induction of membrane damage, and oxidation of cellular lipids and proteins. Many traditional plant treatments for diabetes mellitus are used throughout the world. Management of diabetes without any side effects is still a challenge to the medical system. This leads to increasing demand for natural products with antidiabetic activity and fewer side effects. Many herbs and plant products have been shown to have hypoglycemic action. Aloe vera (L.) BURM. fil. (synonym A. barbadensis MILLER) (Liliaceae), native in North Africa, is one of these antidiabetic plants. Aloe species have been used for centuries for their various healing properties. In the last decade there have also been reports on the antidiabetic activity of Aloe extracts. The Aloe plant contains anthraquinone glycosides, especially in the latex which is different from the gel, polysaccharides, aloeresins, glycomannans and b-sitosterol. Antioxidative phenolic compounds were recently isolated from Aloe barbadensis and identified as aloeresin derivatives. In our previous studies we have reported the blood glucose lowering effect of Aloe vera leaf pulp and gel extracts on neonatal streptozotocin (n0STZ)-induced type-II diabetic rats in acute and chronic treatment. It is well known that STZ causes diabetes by the selective degeneration of pancreatic bcells. To date, research on traditional antidiabetic plants has been especially focused on STZ-induced type-I diabetic rats. It is assumed that herbal medicine can only be effective as an alternative to oral hypoglycemic agents, in type-II diabetes where pancreatic islets are not totally destroyed. That is why, n0STZ-induced type-II diabetic rats were used in our investigation as well as glibenclamide, a known hypoglycemic agent, for comparison. The present study was carried out to evaluate whether Aloe leaf pulp and gel extracts had any protective or harmful effect on the liver injury caused by type-II diabetes in n0STZ-induced diabetic rats.