We demonstrated that PDN combined with DHA attenuates SLE by regulating M1/M2 balance through MAPK signaling pathway. These findings propose that the combination of PDN and DHA could serve as a promising therapeutic strategy for SLE, as it has the potential to mitigate kidney damage and reinstate the equilibrium of M1 and M2 cells.

SLE mice model was established by pristane induction. Flow cytometry was employed to measure the abundance of M1 and M2 cells within the peripheral blood of individuals diagnosed with SLE. The concentrations of various cytokines, namely TNF-α, IL-1β, IL-4, IL-6, and IL-10, within the serum of SLE patients or SLE mice were assessed via ELISA. Immunofluorescence staining was utilized to detect the deposition of IgG and complement C3 in renal tissues of the mice. We conducted immunohistochemistry analysis to assess the expression levels of Collagen-I, a collagen protein, and α-SMA, a fibrosis marker protein, in the renal tissues of mice. Hematoxylin-eosin staining, Masson's trichrome staining, and Periodic acid Schiff staining were used to examine histological alterations. In this study, we employed qPCR and western blot techniques to assess the expression levels of key molecular markers, namely CD80 and CD86 for M1 cells, as well as CD206 and Arg-1 for M2 cells, within kidney tissue. Additionally, we investigated the involvement of the MAPK signaling pathway. The Venny 2.1 online software tool was employed to identify shared drug-disease targets, and subsequently, the Cytoscape 3.9.2 software was utilized to construct the "disease-target-ingredient" network diagram. Protein-protein interactions of the target proteins were analyzed using the String database, and the network proteins underwent enrichment analysis for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways.

Dihydroartemisinin (DHA) plays a very important role in various diseases. However, the precise involvement of DHA in systemic lupus erythematosus (SLE), relation to the equilibrium between M1 and M2 cells, remains uncertain. Therefore, we aimed to investigate the role of DHA in SLE and its effect on the M1/M2 cells balance.

The results showed that an increase in M1 cells and a decrease in M2 cells within the peripheral blood of individuals diagnosed with SLE. Further analysis revealed that prednisone (PDN) combined with DHA can alleviate kidney damage and regulate the balance of M1 and M2 cells in both glomerular mesangial cells (GMC) and kidney. The MAPK signaling pathway was found to be involved in SLE kidney damage and M1/M2 balance in the kidney. Furthermore, PDN and/or DHA were found to inhibit the MAPK signaling pathway in GMC and kidney.