Abelmoschus esculentus fractions potently inhibited the pathogenic targets associated with diabetic renal epithelial to mesenchymal transition

Although Abelmoschus esculentus (AE) is known for anti-hyperglycemia, few reports have addressed its target. Our recent studies have focused on diabetic renal epithelial to mesenchymal transition (EMT), which plays a critical role in fibrosis that accompanies increasing vimentin and suggested signals DPP-4/AT-1/TGF-β1. This study aimed to investigate whether AE is useful for preventing diabetic renal EMT. We used a succession of extractions and obtained the corresponding fractions F1-F5, each with its own individual properties: F1 inhibits high glucose-stimulated vimentin, AT-1, TGF-β1, and DPP-4, and recovers E-cadherin in tubular cells; F2 decreases high glucose-induced vimentin, AT-1 and DPP-4; F3-F5 do not reduce the expression of vimentin. Chemical analysis revealed that F1 is rich of flavonoid glycosides especially quercetin glucosides, and pentacyclic triterpene ester. F2 contains a large amount of carbohydrates and polysaccharides composed of uronic acid, galactose, glucose, myo-inositol etc. In conclusion, AE has the potential to serve as an adjuvant for diabetic nephropathy, with F1 and F2 especially deserving further investigation and development.