Effects of Averrhoa carambola L. (Oxalidaceae) juice mediated on hyperglycemia, hyperlipidemia, and its influence on regulatory protein expression in the injured kidneys of streptozotocin-induced diabetic mice.

Recently, many reports have shown that Averrhoa carambola L. (Oxalidaceae) juice (EACJ) could reduce blood glucose in humans. However, its mechanisms have not been well explored; therefore, our study aimed to investigate the beneficial effects of EACJ on hyperglycemia, hyperlipidemia and renal injury in streptozotocin (STZ)-induced diabetic mice. Those mice were injected with STZ via the tail vein (120 mg/kg body weight) and were identified as diabetic mice when the level of blood glucose was ≥ 11.1 mmol/L. Those mice were intragastriced gavage with saline, EACJ (25, 50, 100 g/kg body weight/d) and metformin (320 mg/kg body weight/d) for 21 days. The fasting blood glucose (FBG), free fatty acids (FFA), total cholesterol (TC), triglycerides (TG), Scr (CREA) and blood urea nitrogen (BUN) were significantly decreased, while the sorbitol dehydrogenase (SDH), Cyclic Adenosine monophosphate (cAMP), malondialdehyde (MDA), superoxide dismutase (SOD), and insulin were elevated. Diabetes-dependent alterations in the kidney, such as glomerular hypertrophy, thicken and tubular basement membrane, were improved after 21 days of EACJ treatment. Hyperglycemia, renal formation and the expressions of related proteins such as connective tissue growth factor (CTGF) and transforming growth factor beta 1 (TGF-β1) were markedly decreased by EACJ. These results indicate that EACJ treatment decrease hyperglycemia, hyperlipidemia and inhibit the progression of diabetic nephropathy (DN), which may be linked to regulating several pharmacological targets for treating or preventing DN.