Triptolide and l-ascorbate palmitate co-loaded micelles for combination therapy of rheumatoid arthritis and side effect attenuation.

Triptolide (TP) has its unique curative effect in the treatment of rheumatoid arthritis (RA), but its application is limited by the poor water solubility and multi-organ toxicity. We herein developed a novel nanoparticle platform composed of L-ascorbate palmitate (VP, vitamin C derivative) that can deliver TP to synergistically treat arthritis and inhibit the occurrence of oxidative stress. The TP-loaded nanoparticles (termed TP-VP NPs) showed the suitable particle size (about 145 nm) and good physical stability. TP-VP NPs effectively down-regulated IL-1β, IL-6 and TNF-α levels to inhibit the erosion of synovitis and bone tissue, and alleviate the swelling and deformation of CIA mice's feet. Compared to the TP, TP-VP NPs could inhibit effectively the oxidative stress in liver, and alleviate significantly the triptolide-induced toxicity injury in liver, kidney and testicle. The results demonstrated that TP-VP NPs is a promising triptolide delivery system for the treatment of RA, which enhances the water solubility of TP and reduces the toxicity of TP in vivo.