Polyphenols of Hibiscus sabdariffa improved diabetic nephropathy via regulating the pathogenic markers and kidney functions of type 2 diabetic rats

► HPE inhibits albuminuria and glomerular hyperfiltration in early diabetic nephropathy. ► HPE inhibits fat deposition and AGE expression in type 2 diabetic kidneys. ► HPE reduces tubular CTGF and glomerular CD31. ► HPE reversed collagen accumulation. ► HPE decreased AT-1 elevation, while improving the oxidative stress.