[Inflammation, oxidative stress and kidney function in arterial hypertension]

Traditional risk factors such as hypertension, diabetes, dyslipidemia, obesity and metabolic syndrome, as well as additional nontraditional risk factors, can damage the kidney directly and by promoting intrarenal atherogenesis. Evidence indicates that increased oxidative stress and inflammation may mediate most of the effects of risk factors on the kidney. An early sign of impending nephropathy is microalbuminuria, defined as urinary excretion of albumin at a rate of 20-200 mg/min. Patients with microalbuminuria, especially in diabetes, may progress along the renal continuum to chronic kidney disease (CKD) (indicated by macroalbuminuria or proteinuria), increased serum creatinine concentration and decreased glomerular filtration rate. Microalbuminuria is now recognized as an important marker not only for renal disease, but above all for cardiovascular risk. Clinical studies have demonstrated a relationship between oxidative stress and inflammatory biomarkers, and a few studies indicate an inverse correlation of oxidative stress biomarkers, assessed by 8-isoprostaglandin F2 alpha, with estimated glomerular filtration rate (eGFR). Moreover, plasma concentrations of high-sensitivity C-reactive protein have been shown to be increased and related to left ventricular mass in CKD individuals having left ventricular hypertrophy. Further, surrogate indexes of atherosclerosis such as intima-media thickness and aortic pulse wave velocity have been demonstrated to be related to plasma concentrations of markers of endothelial activation, inflammation and fibrosis in patients with different stages of CKD. In conclusion, current evidence supports a central role for inflammation in all phases of the atherosclerotic process. On the other hand, in arterial hypertension experimental and clinical data suggest a possible interplay of inflammatory molecules with both oxidative stress and endothelial activation markers. The identification of novel biomarkers and cardiovascular risk factors is needed for prognostic evaluation, cardiovascular and renal prevention, and slowing renal function decline.