Topical Application of Vitamin D3-Loaded Hybrid Nanosystem to Offset Imiquimod-Induced Psoriasis

Abstract
Lipid-polymer hybrid nanoparticles display several benefits over either lipid and/or polymer based systems with respect to enhanced drug loading, good colloidal stability, sustained release profile, and high cellular uptake. The present work rivets on development and evaluation of vitamin D3-loaded monolithic lipid-polymer hybrid nanoparticles (VD3/LPHNPs) for their in vivo anti-psoriatic efficacy. These LPHNPs were prepared using a hot homogenization method and exhibited spherical morphology with a lower particle size (123.1 nm) with narrow PDI (0.234) and efficient encapsulation (76.80%). Further, these LPHNPs demonstrated a sustained release profile of VD3 for up to 3 days following a Korsemeyer-Peppas release model. Further, VD3/LPHNPs were formulated into a topical gel containing 0.005% w/w of VD3. Rheological data suggested that the product exhibited non-newtonian flow properties with characteristic shear-thinning and variable thixotropy features that are desirable for topical formulation. The successful formation of gel structure and its long-term stability were confirmed from the oscillatory studies such as amplitude and frequency sweep tests. In vivo efficacy assessment in imiquimod-induced psoriatic mouse model demonstrated enhanced anti-psoriatic activity of VD3 with improved PASI score when delivered as LPHNPs gel as compared to the free VD3 gel that were further supported by histopathology and immunohistochemistry. Graphic Abstract