In situ evaluation of podocytes in patients with focal segmental glomerulosclerosis and minimal change disease

PLoS One. 2020 Nov 4;15(11):e0241745. doi: 10.1371/journal.pone.0241745. eCollection 2020.

Abstract

Podocyte injury in focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) results from the imbalance between adaptive responses that maintain homeostasis and cellular dysfunction that can culminate in cell death. Therefore, an in situ analysis was performed to detect morphological changes related to cell death and autophagy in renal biopsies from adult patients with podocytopathies. Forty-nine renal biopsies from patients with FSGS (n = 22) and MCD (n = 27) were selected. In situ expression of Wilms Tumor 1 protein (WT1), light chain microtubule 1-associated protein (LC3) and caspase-3 protein were evaluated by immunohistochemistry. The foot process effacement and morphological alterations related to podocyte cell death and autophagy were analyzed with transmission electronic microscopy. Reduction in the density of WT1-labeled podocytes was observed for FSGS and MCD cases as compared to controls. Foot process width (FPW) in control group was lower than in cases of podocytopathies. In FSGS group, FPW was significantly higher than in MCD group and correlated with proteinuria. A density of LC3-labeled podocytes and the number of autophagosomes in podocytes/ pedicels were higher in the MCD group than in the FSGS group. The number of autophagosomes correlated positively with the estimated glomerular filtration rate in cases of MCD. The density of caspase-3-labeled podocytes in FSGS and MCD was higher than control group, and a higher number of podocytes with an evidence of necrosis was detected in FSGS cases than in MCD and control cases. Podocytes from patients diagnosed with FSGS showed more morphological and functional alterations resulting from a larger number of lesions and reduced cell adaptation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Autophagosomes / metabolism
  • Autophagy
  • Case-Control Studies
  • Caspase 3 / metabolism
  • Female
  • Glomerular Filtration Rate
  • Glomerulosclerosis, Focal Segmental / metabolism
  • Glomerulosclerosis, Focal Segmental / pathology*
  • Humans
  • Kidney / metabolism
  • Kidney / pathology
  • Male
  • Microtubule-Associated Proteins / metabolism
  • Middle Aged
  • Necrosis
  • Nephrosis, Lipoid / metabolism
  • Nephrosis, Lipoid / pathology*
  • Podocytes / cytology
  • Podocytes / metabolism
  • Podocytes / pathology*
  • Proteinuria / complications
  • WT1 Proteins / metabolism

Substances

  • MAP1LC3A protein, human
  • Microtubule-Associated Proteins
  • WT1 Proteins
  • Caspase 3

Grants and funding

The authors appreciate the financial support of Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Fundação de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG), and Fundação de Ensino e Pesquisa de Uberaba (FUNEPU).