How many podocyte autophagosomes are there in immunoglobulin A nephropathy and idiopathic membranous nephropathy?

Abstract

Purpose: The aim of this study was to investigate the number of autophagosomes in podocyte from kidney tissue of immunoglobulin A nephropathy (IgAN) and idiopathic membranous nephropathy (IMN).

Methods: The changes in kidney tissue pathology were detected after hematoxylin and eosin, periodic acid-Schiff, Masson's trichrome and immunofluorescence. The autophagosomes of podocyte were analyzed by transmission electron microscopy. Clinical data, including age, gender, edema, serum creatinine, estimated glomerular filtrating rate (eGFR), hematuria, urine protein excretion and serum albumin, were collected from inpatient medical record.

Results: It was found that the number of autophagosomes in podocyte of nephropathy group was lower when compared to the control group. At the same time, we did not find the difference of the parameter between these two kinds of nephropathy. Further study showed that the index was affected by two factors: eGFR and gender. The cases with worse eGFR (eGFR < 60 ml/min) and male patients presented more autophagosomes. Furthermore, each nephropathy had its own character. The phenomena of reduced autophagosomes were found in IMN cases, did not change from male to female, and further aggravated from pathological stage I to II. By contrast, IgAN cases with less eGFR exhibited more autophagosomes.

Conclusions: Therefore, the results of the present study indicate that autophagy participates in podocyte injury and the progression of IgAN and IMN.

Keywords: Autophagosome; Idiopathic membranous nephropathy; Immunoglobulin A nephropathy; Podocyte.