Topical Delivery of Curcumin and Caffeine Mixture-Loaded Nanostructured Lipid Carriers for Effective Treatment of Psoriasis

Background: Curcumin (CUR) is a well-known herbal constituent used in treating psoriasis. However, combination of CUR with other anti-inflammatory drugs such as caffeine shows amplified antipsoriatic action compared to CUR alone. Objective: The objective of the present study was to develop nanostructured lipid carriers (NLCs)-based topical gels of CUR and caffeine combination for facilitated treatment of psoriasis. Materials and Methods: Preparation of NLC's loaded with CUR and caffeine was done by hot homogenization and ultrasonication methods and incorporated in topical gels. Factorial design (32) was constructed in a fully randomized manner to formulate and evaluate all nine possible experimental runs. Detailed evaluation studies for NLC and NLC-based gels were conducted. In vivo animal studies were carried out for optimized formulation using mouse model of imiquimod-induced psoriasis. Results: The physical and chemical characteristics displayed by the prepared NLC's (F1-F9) and gels were found to be optimal. The optimization using experimental design approach resulted in achieving formulation F10 with 103.01 nm particle size and 61.52% entrapment efficiency. In vivo and histopathology studies revealed that prepared NLC-based gel exhibits promising antipsoriatic activity. Conclusion: The present study signified that the CUR and caffeine combination has better antipsoriatic activity. Moreover, NLC-loaded gels have provided sustained drug release till the end of 12 h.