Combination of aspirin with telmisartan suppresses the augmented TGFβ/smad signaling during the development of streptozotocin-induced type I diabetic nephropathy

Diabetic nephropathy (DN) is the most common indication for the development of end stage renal diseases. Inflammation is increasingly seen as the core process in the development of diabetes. Inflammatory markers e.g. NF kappa B (p65 levels), TNF alpha, COX-2 and TGF beta-smad signaling are the key elements in the development of DN. Renin-angiotensin system suppressors like telmisartan have been used to treat DN, but they are not able to prevent completely because of development of resistance against them. Anti-inflammatory agents like, aspirin acts through both COX dependent and COX independent pathways. Hence, we thought that combining aspirin with telmisartan will be better therapeutic option in preventing the progression of nephropathy in diabetes. In the present study we studied the effect of this combination on inflammatory markers [COX-2, NF kappa B (p65 levels), TNF alpha], TGF beta-smad expression in preventing the progression of streptozotocin-induced type I diabetic nephropathy. Treatment of aspirin significantly prevented the progression of nephropathy and inhibited the augmented COX-2, NF kappa B (p65 levels), TNF alpha, and TGF beta-smad expression. Combination of aspirin with telmisartan resulted in a further decrease in the development of nephropathy and inflammatory markers in comparison to aspirin alone treatment. This is the first report which shows that aspirin in combination with telmisartan is more proficient in the treatment of diabetic nephropathy than any single drug therapy and involves the change in expression of inflammatory markers and TGF beta-smad signaling. (C) 2010 Elsevier Ireland Ltd. All rights reserved.