Abstract:

Objective To investigate the mechanism of Qihuang Jianpi Zishen Granules (QJZ) for ameliorating renal damage in MRL/lpr mice. Methods With 6 female C57BL/6 mice as the normal control group, 30 female MRL/lpr mice were randomized into model group, QJZ treatment groups at low, moderate and high doses, and prednisone treatment group (n=6). After 8 weeks of treatment, the mice were examined for 24-h urine protein, creatinine and albumin levels, serum levels of IgG, complement 3 (C3), C4, anti-dsDNA, interferon γ (IFN‑γ) and interleukin 17 (IL-17). Kidney tissues were sampled for histopathological examination with HE staining and observation of glomerular ultrastructure changes using transmission electron microscopy (TEM). The expressions of MyD88/NF-κB pathway-related molecules in the kidney tissue were detected using RT-qPCR, Western blotting and immunohistochemistry. Results Compared with those in the model group, the mice treated with QJZ at the 3 doses and prednisone showed significant reductions in the renal injury biomarkers and serum IgG, anti-dsDNA, IFN‑γ and IL-17 levels and elevation of serum C3 and C4 levels. HE staining revealed lessened glomerular endothelial cell proliferation and mesangial thickening in all the treatment groups. TEM observation further demonstrated reduced electron-dense deposits and diminished inflammatory cell infiltration in the glomeruli in the intervention groups. QJZ at the 3 doses and prednisone treatment all significantly lowered renal expression levels of MyD88, NF-κB, p65 and p52 in the mouse models. Conclusion QJZ can improve renal damage in MRL/lpr mice possibly by inhibiting overactivation of the MyD88/NF-κB pathway.

Key words: MRL/lpr mice, MyD88/NF?κB pathway, systemic lupus erythematosus, renal damage, Qihuang Jianpi Zishen Granules