OXIDATIVE STRESS BIOMARKERS IN LUPUS PATIENTS WITH NEPHROPATHY

BONA, NAZARENO; DITARANTO, PAULINA; BALBI, BÁRBARA; BASIGLIO CL; PEZZARINI, ELEONORA; SVETAZ, MARÍA JOSÉ; BEARZOTTI MARIELA; BOTTAI, HEBE; DANIELE, STELLA; ROSSI, MARÍA FLORENCIA; TAURIZANO, NATALIA; MONJE, ADRIANA; PELUSA HF; ARRIAGA SANDRA

Buenos Aires

Congreso; Reunión Conjunta de Sociedades Biomédicas; 2017

SAIC, SAFIS, SAH, SAB, SAB, SAFE, SAI, SAIB,

Renal compromise in patients with systemic lupus erythematosus is an important cause of morbimortality. Experimental evidence suggests the involvement of oxygen reactive species as primary mediators in the pathogenesis of renal damage produced by ischemic, toxic and immunological processes. Our aim was to characterize the redox status in patients with active lupus nephropathy (ALN) and to determine whether any of the oxidative stress (OS) markers studied correlate with the urinary protein/urinary creatinine index (P/Cr), a traditional marker of renal activity. Twenty-two patients with ALN and 25 patients with inactive lupus nephropathy (ILN) were studied. As OS biomarkers we assessed: a) catalase activity (CAT; UI/g Hb) by a kinetic method; b) superoxide dismutase activity (SOD; U/gHb) by a commercial enzymatic technique; and c) lipid peroxidation by the thiobarbituric acid reactive substances method [TBARS; pmol malondialdehyde/g creatinine (pmol MDA/g Cr)]. P/Cr index (g/g) was determined by a colorimetric/kinetic method. The results obtained, expressed as median (range), in patients with ALN and ILN were, respectively, CAT: 33 (6-81) vs 35 (6-97); SOD: 971 (258-2280) vs 1026 (31-2101); TBARS: 47 (0-172) vs 24 (0-157) y P/Cr: 0.83 (0.37-6.6) vs 0 (0-0.2). Statistically significant differences between both groups were found for TBARS (p=0.025) and for P/Cr (p=0.001). None of the biomarkers studied significantly correlated with P/Cr. We conclude that, in the sample analyzed, there is a disbalance in the redox status that would be involved in lipid peroxidation of the basal membrane, thus altering its integrity and also affecting tubular function in patients with ALN. Consequently, TBARS could be used as an additional marker of activity in renal disease together with parameters commonly used in clinical laboratory practice.