Co-delivery of indomethacin and uricase as a new strategy for inflammatory diseases associated with high uric acid.

Uric acid is the final metabolite in humans. High level of uric acid chronically induces urate deposition, aggravates kidney damage, and concomitantly causes an increase in inflammatory factors. Alleviating acute inflammation and decreasing uric acid levels are the key points in the treatment of inflammatory diseases associated with high uric acid. However, a drug delivery system that combines anti-inflammatory and uric acid reduction functions at the same time remains a challenge to be settled. Here, we designed a nanocrystal-based co-delivery platform, IND Nplex, characterized by loading of indomethacin (IND) and uricase. Compared with free IND or uricase, IND Nplex possessed a better anti-inflammatory effect by restraining the release of inflammation-related factors in vitro. In addition, pharmacokinetic and biodistribution studies revealed that IND Nplex significantly prolonged the retention time in vivo and was more concentrated in the kidney. In acute gouty arthritis model rats, IND Nplex markedly relieved ankle joint swelling and mitigated synovial inflammation. In acute kidney injury model rats, IND Nplex indicated better biocompatibility and significant amelioration of renal fibrosis. Moreover, IND Nplex showed the effect of anti-inflammatory and improved renal function via determination of inflammatory factors and biochemical markers in the serum and kidney. In conclusion, these results indicate that IND Nplex exerts anti-inflammatory activity and uric acid-lowering effect and could become a promising candidate for the treatment of uric acid-related diseases.

Silymarin nanoliposomes attenuate renal injury on diabetic nephropathy rats via co-suppressing TGF-ß/Smad and JAK2/STAT3/SOCS1 pathway.

AIMS: To investigate the improvement and mechanisms of silymarin on renal injury in mouse podocytes and streptozotocin (STZ)-induced diabetic nephropathy model (DN) rats. MAIN METHODS: Firstly, the effects of silymarin on the cell viability and cellular injury-related indicators of high-glucose incubated mouse podocytes MPC-5 were assessed by CCK-8 and western blotting (WB) methods, respectively. The STZ-induced diabetic rats with DN were treated with silymarin nanoliposomes at three doses for consecutive 8-week. General metabolic indicators, renal functions and lipid accumulation-related factors were all measured. The renal tissue sections were stained and observed via hematoxylin-eosin (H&E) staining method. Real-time RT-PCR and WB methods were utilized to measure the expression of JAK2/STAT3/SOCS1 and TGF-ß/Smad signaling pathway related factors. KEY FINDINGS: Silymarin significantly improve the high-glucose induced up-regulation of podoxin and nephrin, as well as the expression of inflammatory cytokines IL-6, ICAM-1 and TNF-α, and the cell survival rates were also significantly increased in a dose-dependent manner. Significant improvement on body weight/kidney ratio, renal functions and lipid profiles in renal tissues were observed in STZ-induced diabetic rats after chronic silymarin treatment. The H&E staining exhibited that the pathological damages in renal tissues were obviously improved. Moreover, silymarin nanoliposomes treatment notably suppressed expression levels of inflammation-related proteins as well as IL-6 and ICAM-1, and regulated JAK2/STAT3/SOCS1 and TGF-ß/Smad signaling pathway, thereby exhibited protective effects on kidney of DN model rats. SIGNIFICANCE: Silymarin nanoliposomes ameliorate STZ-induced kidney injury by improving oxidative stress, renal fibrosis, and co-inhibiting JAK2/STAT3/SOCS1 and TGF-ß/Smad signaling pathways in diabetic rats.