Hexosaminidase activity of erythrocytes plasma membrane as a possible biomarker of oxidative stress and kidney conditions in old patients with chronic renal failure under renal replacement therapy

The hexosaminidase (Hex) and its isoformes are ubiquitous enzymes (1). Several studies underline strong relation between their levels in body fluids and pathologies or different degree of complications as shown for plasma levels of Hex in diabetes (2) or urinary Hex in nephropathy (3). Recently, Hexs are found and deeply studied in plasma membrane and in cytosol of human erythrocytes (4). Red cells are a useful model for investigating physio-pathological conditions; erythrocyte glycohydrolases, particularly the Hexosaminidase (Hex), are considerate new and sensitive oxidative stress markers (5). Renal replacement therapies (RRT) exposes patients to oxidative stress increasing the inflammatory state already present (6). We assessed Hex activity on erythrocyte’s plasma membrane in 11 Chronic Renal Failure (CRF) patients on conservative treatment, in 15 on peritoneal dialysis (PD), in 12 on haemodialysis, before (HD-pre) and after (HD-post) a treatment and compared these to 30 healthy controls to evaluate the role of different RRT on oxidative stress. Moreover, we compared for their behaviour Hex and total plasmatic antioxidant defences (LagTime) analyzed in our previous study. In CFR patients, Hex activity show a significant increase respect to controls (p<0.001). It’s remarkable that, with the progression of the pathology (and through different RRT), the activity decreased until, in HD patients, values similar to controls. This suggest, in HD patients, a minor oxidative stress exactly how indicated from Lag-time in our precedent study. Evidence strengthened by the negative correlation between Hex e Lag-time. Data confirmed the role of Hex as early biomarker of oxidative stress and consequent cellular damages and highlighted positive effects of RRTs suggesting HD how the least oxidant treatment as RRT for older patients. Results remark a possible role of this enzyme as a marker of kidney conditions and as a further signal to start RRT.