Transdermal fluocinolone acetonide loaded decorated hyalurosomes cellulose acetate/polycaprolactone nanofibers mitigated Freund’s adjuvant-induced rheumatoid arthritis in rats

Abstract Purpose This study aimed to develop a transdermal delivery system for fluocinolone acetonide (FLA), a corticosteroid used in treating inflammatory conditions like rheumatoid arthritis (RA), to overcome the limitations of oral administration, such as poor solubility and bioavailability. Methods FLA-loaded PEG decorated hyalurosomes (FLA-PHs) were fabricated using ethanol injection, incorporating various Brij® surfactants and different amounts of hyaluronic acid (HA) based on a full factorial design. The impact of independent variables, HA amount (mg) (X 1 ) and Brij type (X 2 ) were inspected for entrapment efficiency (EE%), particle size (PS), and zeta potential (ZP). The optimum FLA-PHs were then incorporated into ε-polycaprolactone (PCL) and cellulose acetate (CA) nanofibers to enhance sustained transdermal delivery (FLA-NFs). Results The optimum FLA-PHs exhibited EE% of 83.58 ± 0.69%, PS of 169.00 ± 1.41 nm, and ZP of -22.90 ± 0.14 mV. Morphological assessment of FLA-NFs showed promising results in terms of surface roughness. In a Freund-induced rat model of adjuvant-induced arthritis, transdermal treatment with FLA-NFs significantly improved joint histopathological analyses. Furthermore, it suppressed inflammatory markers such as mTORC1, TNF-α, and NF-κB while upregulating TRIM24 and the anti-inflammatory IL-10. Conclusion FLA-NFs present a promising strategy for enhancing the transdermal delivery of FLA for managing RA, offering potential improvements in efficacy and reduced systemic side effects compared to conventional oral administration.