STRUCTURAL AND FUNCTIONAL CHARACTERISTIC OF HUMAN PODOCYTES IN PODOCYTOPATHIES

Abstract

Ultrastructural characteristics of the foot processes fusion and glomerular basement membrane (GBM) denudation were studied as a manifestation of podocyte (PC) dysfunction. The following variants of podocytopathies were analyzed: focal segmental glomerulosclerosis (n=8), membranous nephropathy (n=17), minimal change disease (n=12). Renal biopsy material was examined by light and electron microscopy with the determination of some morphometric indices. Morphological data were compared with the results of standard laboratory tests of renal function. In various podocytopathies significant changes in the ultrastructure of PC were observed that caused the disorders of the selective permeability the glomerular filter. These dysfunctional changes were characterized by foot process fusion and GBM denudation. Negative correlation was found between the glomerulosclerosis severity and glomerular filtration rate - the main indicator of the preservation of renal function. Correlation analysis of the width of foot processes and the extent of GBM denudation demonstrated a statistically significant negative relationship. The changes detected in PC seem to be an adaptive response of the cells, opposing the desquamation from the GBM surface under conditions of stress and action of damaging factors.

Keywords

podocytes / dysfunction / foot process fusion / glomerular basement membrane

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