Lactobacillus rhamnosus LC-STH-13 ameliorates the progression of SLE in MRL/lpr mice by inhibiting the TLR9/NF-κB signaling pathway.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease often treated with glucocorticoids, which can lead to complications such as osteoporosis and an increased infection risk. Hence, identifying safe and effective treatment strategies is crucial. Lactobacillus has shown promise in improving immune disorders. We investigated Lactobacillus rhamnosus LC-STH-13 for its probiotic properties. Female MRL/lpr mice, prone to lupus, were used to assess its impact on SLE development. The results showed that the intervention with L. rhamnosus LC-STH-13 significantly reduced the level of circulating anti-autoantibodies (p < 0.05) and rebalanced Th17/Treg cells (p < 0.05). Kidney tissue analysis revealed reduced immune cell infiltration and immune complex deposition in glomeruli. L. rhamnosus LC-STH-13 mitigated kidney inflammation via the TLR9/NF-κB pathway (p < 0.05) and attenuated complement-induced renal damage (p < 0.05). Furthermore, 16S rRNA sequencing data analysis indicated that L. rhamnosus LC-STH-13 can restore intestinal microecological imbalance caused by the development of SLE. These findings suggested that L. rhamnosus LC-STH-13 improves the development of SLE by regulating the TLR9/NF-κB pathway and intestinal microbiota, offering a foundation for exploring safe and effective treatments.