Enhanced Antipsoriatic Activity of Mycophenolic Acid Against the TNF-α-Induced HaCaT Cell Proliferation by Conjugated Poloxamer Micelles

Abstract

Mycophenolic acid (MPA), an immunosuppressant drug, possesses antimicrobial, anticancer, and antipsoriatic activities. However, the use of MPA in therapeutic applications is limited to its poor oral bioavailability, low aqueous solubility, and undesired gastrointestinal side effects. Polymeric micelles are a drug delivery system that has been used to enhance the water solubility of pharmaceuticals. In this work, poloxamer 407 (P407) and MPA were conjugated via an ester linkage resulting in a P407-MPA conjugate. The P407-MPA conjugate was investigated for micellization, particle size, size distribution, MPA release in phosphate buffer (pH 7.4) and human plasma, and antipsoriatic activity. ¹H-nuclear magnetic resonance suggested that polymeric micelles formed from the P407-MPA conjugate exposed its polyethylene oxide chain to the aqueous environment while restricting the conjugated MPA within the inner core. The P407-MPA conjugate has an improved micellization property with the over 12-fold lower critical micelle concentration compared to P407. The conjugate exhibited an enzyme-dependent sustained-release property in human plasma. Finally, the conjugate exhibited an improved antiproliferation activity in tumor necrosis factor-α-induced HaCaT cells, which is an in vitro psoriasis model. Therefore, the prepared P407-MPA conjugate, with an improved aqueous solubility and biological activity of MPA, has the potential to be further developed for psoriasis treatment.

Keywords: antipsoriatic activity; mycophenolic acid; poloxamer; polymer conjugation; polymeric micelles; psoriasis.