Effects of Ginkgo biloba on prevention of development of experimental diabetic nephropathy in rats

Abstract

To observe the preventive and therapeutic effects of Ginkgo biloba extract (GbE) on early experimental diabetic nephropathy (DN) in rats. After an early DN model was induced by streptozotocin, rats were administered GbE at 3 doses for 12 weeks. Fasting blood glucose, creatinine (Cr), blood urea nitrogen (BUN), urine protein, kidney index, anti-oxidase, advanced glycosylation end products (AGE), collagen IV and laminin, matrix metalloproteinases-2 (MMP-2) and the tissue inhibitor of metalloproteinase-2 (TIMP-2), connective tissue growth factor (CTGF), and transforming growth factor-beta1 (TGF-beta1) mRNA were measured by different methods. The ultrastructural morphology and the thickness of glomerular base membrane (GBM) were observed by a transmission electron microscope. For the GbE-treated DN rats, when compared with the vehicle-treated DN rats, the fasting blood glucose level, Cr, BUN, urine protein level, and the intensity of oxidative stress were significantly decreased. The expression of MMP-2 greatly increased, and TIMP-2 decreased. Also, AGE, either in serum or in renal, the collagen IV, laminin, CTGF levels, and TGF-beta1 mRNA were reduced. Furthermore, both relative grades of mesangium hyperplasia by microscopical observation and the thickness of GBM by electron microscope measurement decreased significantly. GbE has protective effects on several pharmacological targets in the progress of DN and is a potential drug for the prevention of early DN.