Jian Pi Shen Shi formula alleviates hyperuricemia and related renal fibrosis in uricase-deficient rats via suppression of the collagen-binding pathway

Aim: Jian Pi Shen Shi Formula (JPSSF) is a beneficial treatment for hyperuricemia and related tissue damage in the clinical setting. This study was designed to investigate its therapeutic potential and underlying mechanisms in uricase-deficient rats (Uox^-/- rats).

Methods: Uox^-/- rats were used to assess the therapeutic potential of JPSSF on hyperuricemia. Protein extracts from renal tissues of a Uox^-/- group and a JPSSF group were analyzed using tandem mass tag labeling quantitative proteomic workflow. Collagen deposition in Uox^-/- rat kidneys was analyzed by Masson trichromatic staining. The gene expression associated with collagen-binding-related signaling pathways in the kidneys was further explored using quantitative polymerase chain reaction assay. The protein expressions of collagen 1a1 (col1a1), col6a1, and α-smooth muscle actin were measured by Western blotting and immunohistochemistry.

Results: JPSSF significantly decreased renal function indices and alleviated renal injuries. The action of JPSSF was manifested by down-regulation of col6a1 and interleukin-1 receptor-associated kinase-like 2, which blocked the binding sites on collagen and further prevented kidney injury. The anti-renal fibrosis effect of JPSSF was confirmed by reducing the collagen deposition and hydroxyproline concentrations. JPSSF treatment also intensely down-regulated the mRNA and protein expressions of col6a1, col1a1, and α-smooth muscle actin, which inhibited the function of the collagen-binding-related signaling pathway.

Conclusion: Our results indicated that JPSSF notably ameliorated hyperuricemia and related renal fibrosis in Uox^-/- rats through lowering uric acid and down-regulating the function of the collagen-binding pathway. This suggested that JPSSF is a potential empirical formula for treating hyperuricemia and accompanying renal fibrosis.