Silencing of CXCL12 performs a protective effect on C5b-9-induced injury in podocytes

Podocytes, terminal differentiation cell in glomerulu, are crucial to kidney-related diseases such as membranous nephropathy (MN). MN is characterized by podocyte injury and glomerular basement membrane thickening. This paper focused to investigate the expression of chemokine (C-X-C motif) ligand 12 (CXCL12) in MN patients and its possible role in podocyte injury.

Through the enzyme-linked immunosorbent assay, CXCL12 level in the serum and urine of MN patients was examined. Further, several assays of cell viability, apoptosis, quantitative real-time PCR and western blot were applied to explore the effects of CXCL12 in the model of podocyte injury.

We found a significant increase of CXCL12 in serum and urine of MN patients, which indicated that CXCL12 may be involved in the progression of MN. And in vitro C5b-9-induced podocyte injury model, the proliferation of podocytes was inhibited whereas CXCL12/CXCR4 and phosphorylated STAT3 (p-STAT3) were increased. Silencing of CXCL12 remarkably promoted cell proliferation, inhibited cell apoptosis and suppressed CXCL12/CXCR4, p-STAT3 and caspase 3. Consistently, STAT3 inhibitor and berberine (a CXCL12 antagonist) also reduced CXCL12 treatment-induced apoptosis.

All data suggested that silencing of CXCL12 had a protective effect on podocyte injury, which may be through inhibiting CXCL12/STAT3 signaling pathway.