Biodistribution, hypouricemic efficacy and therapeutic mechanism of morin phospholipid complex loaded self-nanoemulsifying drug delivery systems in an experimental hyperuricemic model in rats

OBJECTIVES: This study aimed to compare the biodistribution and hypouricemic efficacy of morin and morin-phospholipid complex loaded self-nanoemulsifying drug delivery systems (MPC-SNEDDS), as well as to explore their therapeutic mechanisms. METHODS: We studied the biodistribution of morin and MPC-SNEDDS after they were orally administered to rats. The hypouricemic efficacy and the therapeutic mechanisms of morin and MPC-SNEDDS were evaluated using potassium oxonate-induced hyperuricemic model in rats. KEY FINDINGS: With enhanced morin concentration in liver and kidney, oral delivery of MPC-SNEDDS exhibited significantly stronger urate-lowering effect in hyperuricemic rats than morin. The hypouricemic efficacy of morin was due to reduced production of uric acid via inhibiting the mRNA expression of hepatic xanthine dehydrogenase/xanthine oxidase (XDH/XO), as well as decreased urate reabsorption via modulating the alteration of mRNA levels of glucose transporter (mGLUT9), renal organic anion transporter 1 (mOAT1) and uric acid transporter (mURAT1). MPC-SNEDDS dually inhibited mRNA expression and activity of hepatic XDH/XO and restored the dysregulation of renal mGLUT9, mOAT1 and mURAT1, contributing to its superior urate-lowering efficacy. CONCLUSION: The results demonstrated the great potential of MPC-SNEDDS as an alternative oral strategy for active agents in treating hyperuricemia.