Overproduction of Mitochondrial Fission Proteins and Mitochondrial Fission in Podocytes of Lupus Nephritis Patients.

BACKGROUND

The glomerular injury is associated with different pathogeneses, and podocyte damage is common in various ISN/RPS class lupus nephritis (LN). In podocyte, mitochondrial morphological changes are observed in lupus nephritis (LN) in our previous study. This study aimed to explore mitochondrial fission proteins expression in podocytes using bioinformatics analysis and further to investigate the associations between mitochondrial fission proteins and laboratory features in LN.

METHODS

To determine the differentially expressed genes (DEGs) between LN and normal controls, we downloaded and analyzed microarray datasets. Then download the mitochondrial genes list from the MitoMiner 4.0 database, then take the genes that are common with the DEGs. Functional enrichment analyses were then performed. Then mitochondrial fission was observed through electron microscope. We performed immunofluorescence staining to explore the expression of mitochondrial fission proteins in LN patients.

RESULTS

Among these 658 DEGs, 5 DEGs related to mitochondrial dynamics were identified. Mitochondrial dynamics proteins were involved in mitophagy. Mitochondrial fission proteins Drp1 and Fis1 staining were significantly enhanced compared to that in the controls. 24h-UTP are positively correlated with mitochondrial fission proteins expression.

CONCLUSION

Mitochondrial fission was observed in LN patients' podocytes. Mitochondrial fission proteins Drp1 and Fis1 were overproduced in podocytes, and then they can lead to mitochondrial fission, which may aggravate podocyte damage and proteinuria. While the mechanism still needs to be explored.