Investigating the role of IL-6 in the pathogenesis of systemic lupus erythematosus: Insights from bone marrow mesenchymal stem cells

Systemic lupus erythematosus is a common autoimmune disease. Studies have suggested that defective stem cells could be involved in the pathogenesis of systemic lupus erythematosus, which leads to changes in the function of immune cells. By observing the cell morphology, autophagy, and senescence of bone marrow mesenchymal stem cells (BMSCs) from lupus mice and normal controls, this study investigated the role of IL-6 in autophagy and senescence of BMSCs and explored relevant mechanisms. Female MRL/lpr and C57 mice with similar weights and sizes at 20-22 weeks old were selected. BMSCs were isolated using the whole bone marrow adherent method. Quantitative real-time polymerase chain reaction, β-galactosidase staining, western blotting, and ELISA were used to detect autophagy and senescence. Compared with BMSCs from normal mice, BMSCs from lupus mice exhibited low autophagy and premature senescence with a senescence-associated secretory phenotype. The addition of exogenous IL-6 increased the protein levels of p-STAT3 and Bcl-2, and in the IL-6-treated group, the premature senescence of cells increased and autophagy decreased. The biological functions of BMSCs from MRL/lpr lupus mice were impaired. IL-6 prevents autophagy and subsequently promotes the senescence of BMSCs by activating the IL-6/STAT3 pathway.