Development of Betulin-Loaded Nanostructured Lipid Carriers for the Management of Imiquimod-Induced Psoriasis.

Psoriasis is a complex and persistent autoimmune skin disease. The present research focused on the therapeutic evaluation of betulin-loaded nanostructured lipid carriers (BE-NLCs) towards managing psoriasis. The BE-NLCs were synthesized using the emulsification cum solidification method, exhibiting a spherical shape with a particle size of 183.5±1.82nm and a narrow size distribution window (PDI: 0.142±0.05). A high zeta potential -38.64±0.05mV signifies the relative stability of the nano-dispersion system. BE-NLCs show a drug loading and entrapment efficiency of 47.35±3.25% and 87.8±7.86%, respectively. In vitro release study, BE NLCs show a cumulative percentage release of 90.667±5.507% over BE-sol (57.334±5.03%) and BD-oint (42±4.58%) for 720min. In an ex vivo 24-h permeation study, % cumulative amount permeated per cm2 was found to be 55.667±3.33% from BE-NLCs and 32.012±3.26% from BE-sol, demonstrating a better permeability of 21.66% when compared to the standard formulation BD-oint. The in vivo anti-psoriatic activity in the IMQ-induced model shows topical application of BE-sol, BE-NLCs, and BD-oint resulted in recovery rates of 56%, 82%, and 65%, respectively, based on PASI (Psoriasis Area and Severity Index) score. Notably, BE-NLCs demonstrated a more significant reduction in spleen mass, indicating attenuation of the local innate immune system in psoriatic mice. Reductions in TNF-α, IL-6, and IL-17 levels were observed in both BE-sol and BE-NLCs groups compared to the disease control (DC) group, with BE-NLCs exhibiting superior outcomes (74.05%, 44.76%, and 49.26% reduction, respectively). Soy lecithin and squalene-based NLCs could be better carrier system for the improvement of the therapeutic potential of BE towards management of psoriasis.