RESUMO
In this study, the effects of A. nilotica [AAN] in serum glucose, lipids and hepatic functions were evaluated in normal and streptozotocin [STZ]-induced diabetic rats. The experimental animals were divided into four groups: A normal untreated group orally administered a vehicle for three weeks, a normal AAN-treated group received oral daily dose of AAN [58 mg/kg] for three weeks, a diabetic untreated group injected i.p. with STZ [60 mg/kg] and a diabetic AAN- treated group included STZ-induced diabetic rats received a daily oral dose of AAN extract for three weeks. Serum glucose, triglycerides [TG], cholesterol, alanine minotransferase [ALT], and aspartate aminotransferase [AST] were analyzed. Paraffin-embedded liver sections were used for histopathology and detection of polysaccharides contents and immuno expression of the anti-apoptotic protein Bcl-2. STZ-induced diabetic rats showed significant elevation of serum glucose and hepatic markers [ALT and AST] with hepatic cellular swelling, cytoplasmic alterations, nuclear hypertrophy, cellular damage and depleted hepatic polysaccharides. Administration of AAN produced a significant hypoglycemic effect in normal rats and significant decreases in serum glucose, cholesterol and TG in diabetic rats. Also, AAN stimulated the expression of the Bcl-2 protein in the liver of both normal and STZ-induced diabetic rats and prevented the occurrence of hepatic cellular swelling and damage. However, administration of AAN to normal rats in creased insignificantly ALT and AST levels accompanied with few hepatic cellular changes. Moreover, administration of AAN to diabetic rats did not significantly decrease the elevated serum ALT and AST levels