Hypertension influences the exponential progression of inflammation and oxidative stress in streptozotocin-induced diabetic kidney

OBJECTIVE To investigate the association of hypertension coexisting with diabetes mellitus with oxidative stress and inflammation in the kidneys of streptozotocin (STZ)-induced diabetic rats. MATERIALS AND METHODS Male Wistar rats were used for the experiments. Blood glucose (BG), urea, blood pressure (BP), and heart rate (HR) were analyzed before and 48 h after STZ injection. Further, these parameters were monitored up to 3 months of diabetes induction. Subsequently, the inflammatory markers (C-reactive protein, tumor necrosis factor-alpha, and nitrate) and oxidative stress markers were estimated after 3 months of diabetes induction in the kidney homogenate. Histological analysis of renal tissue was also carried out. RESULTS Linear elevation of BG, urea, mean arterial pressure (MAP), and HR was observed up to 3 months of diabetes induction. In the same manner, inflammatory and oxidative stress markers were also found to be significantly increased. Notably, the histological analysis revealed the signs of nephropathy such as increased mesangial cell number, thickness of basement membrane, and renal artery. Inflammatory and oxidative stress markers positively correlated with elevated BP and BG, but the correlation was better with BP rather than BG. CONCLUSION Hypertension has a strong implication in the increased oxidative stress and inflammation of diabetic kidney at the very early stage of diabetes mellitus.