Antipsoriatic Effect of Silymarin NLCs Based Gel: In Vitro and In Vivo Activity

Psoriasis is a chronic inflammatory disorder affecting over 100 million people, requires long-term therapy. Current treatments offer only symptomatic relief. However, phytoconstituents-based therapies like Silymarin (SLM) have shown promising effects. The study aims to develop, optimize, and evaluate a novel stable SLM NLC gel to improve anti-psoriatic activity by enhancing its permeability and retention into the dermal layer. SLM NLC formulation was prepared and optimized using 3² full factorial designs. The formulation was evaluated for the particle size, PDI, zeta potential, and % entrapment efficiency, evaluated by Transmission electron microscopy and thermal analysis. The freeze dried and prepared NLC-loaded gel was evaluated for physicochemical parameters, ex-vivo, and in-vivo studies. SLM-loaded NLC shows 624 nm particle size, 0.41 PDI, 92.95% entrapment efficiency, and -31.6 mV zeta potential. The sphere form of NLCs was confirmed using TEM. Controlled drug release was observed in ex vivo studies, low PASI score compared to disease control. Further, the levels of IL-6, TNF-α, and NF-κB were also reduced. The results are supported by histopathology showing minimal parakeratosis indicated in the SLM NLC-treated group. Prepared NLC-based shows enhance topical penetration and decrease the thickness of psoriatic plaques in the in vivo study.