Avaliação da autofagia de podócitos e de moléculas do sistema imune reguladoras da da autofagia em biópsias renais pediátricas diagnosticadas com podocitopatias

Abstract

Focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) are the main podocytopathies in childhood, clinically manifesting as nephrotic syndrome. The pathogenesis of these diseases has not yet been fully elucidated; however, the immune system is known to play a central role in the development and progression of glomerular damage. This study stands out as innovative by uniquely evaluating the presence of autophagy in podocytes and its association with the expression of CD36, TNF, IL-10, and inflammasome (NLRP3). Epidemiological data and renal biopsy fragments from 37 children, aged 3 to 18 years, diagnosed with FSGS (n=16) and MCD (n=21) at the Kidney Research Center (CePRim) of the Federal University of Triângulo Mineiro (UFTM) were analyzed. The expression of CD36, TNF, IL-10, and NLRP3 inflammasome was assessed by immunohistochemistry. The presence of autophagy and foot process effacement were evaluated using Transmission Electron Microscopy. Both groups presented proteinuria, hypercholesterolemia, and hypoalbuminemia, with no significant difference. A reduction in CD36 expression was observed in the MCD group compared to the control and FSGS groups, whereas NLRP3 expression was significantly higher in the FSGS group compared to the control. Supporting this finding, autophagic activity in FSGS was significantly higher compared to MCD. No significant differences were observed in TNF and IL-10 expression. The results indicate distinct inflammatory profiles between FSGS and MCD, with FSGS characterized by higher inflammatory activity mediated by the NLRP3 inflammasome, while MCD exhibits lower inflammation, as evidenced by the significant reduction in CD36 expression. These findings suggest CD36 as a potential biomarker for the differential diagnosis between FSGS and MCD and contribute to understanding specific inflammatory pathways, opening new perspectives for individualized therapeutic strategies.