Transferosomes Containing 20-Hydroxyecdysone for Psoriasis Treatment: Preparation, Characterization, and In Vitro and In Vivo Toxicity Assessment.

Background/Objectives: Psoriasis is a chronic, immune-mediated inflammatory skin disorder affecting millions of individuals worldwide. It remains a therapeutic challenge due to the limited skin penetration of many drugs, adverse systemic effects, and the need for long-term management. Transferosomal nanoformulations containing natural products were proposed as a potential therapeutic tool. Methods: Transferosomes containing 20-hydroxyecdysone and resveratrol were prepared using the thin-film hydration method followed by probe ultrasonication, generating several formulation variants differing in composition. The vesicles were characterized by dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) to determine size, polydispersity index (PDI), and zeta potential. Furthermore, time-domain nuclear magnetic resonance (TD-NMR) relaxation measurements were employed to evaluate local molecular dynamics and membrane fluidity, providing deeper insights into the structural integrity and elasticity of the transferosomal systems. The stability of the nanoformulations was assessed for one month in water and phosphate-buffered saline (PBS). Viability was evaluated in vitro using the MTS assay on human epidermal keratinocyte (HEK) and psoriasis-patient derived human epidermal keratinocyte (PHEK) cell lines, alongside antimicrobial profiling against four representative human skin microbiome strains. Acute toxicity was further examined in vivo using the Danio rerio FET test. Results: The formulations demonstrated high physicochemical stability over the tested period, maintained desirable particle sizes within 100-200 nm, and showed no cytotoxicity toward skin-associated bacteria or in the zebrafish model. Conclusions: The developed nanoformulations present suitable properties in terms of safety and stability and can be considered for potential use in psoriasis treatment.