Protective effect of yacon leaves decoction against early nephropathy in experimental diabetic rats

HONORE S. M.; CABRERA W. M.; GENTA S. B.; SANCHEZ S. S.

FOOD AND CHEMICAL TOXICOLOGY

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2012 vol. 50 p. 1704 - 1715

0278-6915

Nephropathy is the most common cause of morbidity and mortality in diabetic patients. Prevention of this complication has a major relevance. Smallanthus sonchifolius (yacon) leaves have been shown to ameliorate hyperglycemia in streptozotocininduced diabetic rats. We examined the beneficial effects of yacon leaves decoction on diabetic nephropaty and explored the possible underlying action mechanism. Streptozotocin-diabetic rats were orally administered 10% yacon leaves water decoction (70 mg dry extract/kg body weigth) once a day for 4 weeks. Biochemical parameters in blood and urine were analyzed and immunohistochemistry staining, western immunoblotting and qRT-PCR were assessed. Yacon decoction significantly decreased high blood glucose level in diabetic rats and improved insulin production. Diabetic-dependent alterations in urinary albumin excretion, creatinine clearance, kidney hypertrophy and basement membrane thickening were attenuated by yacon decoction. These findings were associated with a marked decrease in TGF- b/Smad2/3 signaling. The expression of molecular markers of diabetic nephropathy such as collagen IV, laminin-1, fibronectin and collagen III were also diminished in the yacon-treated group compared to control diabetic group. These results suggest that yacon leaves decoction is a protective agent against renal damage in diabetic nephropathy, whose action can be mediated by TGFb/Smads signals.