Rhubarb could improve the condition of diabetic nephropathy patients by reducing the excretion of urinary protein, lowering blood lipid, improving renal function, regulating the abnormal expression of TGF-β1, MMP-2, MMP-9 and MCP-1 in the blood of diabetic nephropathy patients, inhibiting renal inflammation and fibrosis process [95]. The gene discussed is MMP9; the disease is diabetic kidney disease.