Feeding of banana flower and pseudostem to diabetic rats results in modulation of renal GLUTs, TGFβ, PKC and extracellular matrix components

摘要

Background and aims: Sustained hyperglycemia as a result of diabetes mellitus results in over-expression of glucose transporters (GLUTs/SGLTs), protein kinase C-α (PKC-α) and transforming growth factor-β (TGF-β) in kidney which increases synthesis and accumulation of extracellular matrix (ECM) components leading to diabetic nephropathy. Previous results from our laboratory showed that banana flower (BF) and pseudostem (BS) ameliorated diabetic complications and reduced formation of advanced glycation end-products (AGEs). In this study, attempts were made to delineate the changes observed in GLUTs and ECM components in kidney by feeding BF and BS at the molecular level. Methods and results: Diabetes was induced in male Wistar rats by injecting streptozotocin. Rats were fed with standard AIN-76 diet or diet supplemented with 5% BF or BS. Rats fed with diet supplemented with aminoguanidine (0.05%) were used as a positive control. Effect of BF and BS on expression of GLUTs/SGLTs, PKC and TGF β in kidney was evaluated by RT-PCR and accumulation of ECM components in kidney was quantitated by ELISA and immunohistochemistry. BF and BS modulated the over-expression of GLUT 1, 2, 5, SGLT 1, 2 and factors such as PKC-α and TGF-β to various extents. This impinged on the synthesis of ECM components like laminin, fibronectin and type-IV collagen. Conclusion: The results suggest that BF and BS reduce the diabetic nephropathy complications which are accompanied by changes at the molecular level.