To investigate the protective effect of verapamil on hyperuricemia nephropathy (HN) in mice through modulating TXNIP/NLRP3 inflammasome signaling pathway.

Thirty-two male C57BL/6J mice (8 weeks old, weighing 18~22 g) were randomly divided into a blank control group, a model group, an allopurinol group (10 mg/kg), and a verapamil group (40 mg/kg), with 8 animals in each group. Except for the control mice, the other mice were given 10% fructose water and adenine to establish a mouse model of HN. After successful establishment of model mice, the corresponding interventions were administered to the mice of the other 3 groups for 4 consecutive weeks. The levels of serum uric acid (UA), creatinine (Cr), urea (UREA), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured. HE staining was used to assess the alterations in renal morphology and the infiltration of inflammatory cells, while Masson’s staining was employed to evaluate renal fibrosis. Moreover, ELISA was employed to measure the contents of IL-1β and IL-6 in kidney tissue, while serum levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) were detected by colorimetric assay. Furthermore, immunohistochemical staining and Western blot analysis were conducted to examine the expression of TXNIP, NLRP3, IL-1β, MMP7, FN1, CD68, and MPO proteins in the kidney.

Compared to the control group, HN mice exhibited increased serum UA, Cr, and UREA levels (P<0.05), renal pathological changes including renal tubular regeneration, interstitial or periglomerular fibrosis and prominent infiltration of inflammatory cells, and significantly increased renal contents of IL-1β and IL-6 and serum MDA level (P<0.05), while reduced serum SOD and GSH-Px contents (P<0.05), as well as upregulation of kidney proteins TXNIP, NLRP3, IL-1β, CD68, MPO, FN1 and MMP7 (P<0.01). Verapamil treatment notably reduced serum UA and Cr levels (P<0.01), improved kidney lesions to some extents, decreased collagen volume fraction (CVF) (P<0.01), and restored pro-inflammatory cytokines and oxidative stress markers (P<0.05) when compared with the levels in the model group. Further research found that the expression of kidney proteins TXNIP, NLRP3, IL-1β, CD68, MPO, FN1, and MMP7 was significantly downregulated by verapamil treatment (P<0.05).

Verapamil exhibits a renal protective effect on HN mice through its anti-inflammatory, antioxidant, and antifibrotic properties, and its mechanism may be related to the inhibition of the TXNIP/NLRP3 inflammasome signaling pathway.