039 Effect of Retinoid Loaded Hyaluronic Acid Nanomicelle on Vaginal Epithelium in Mouse Menopausal Model

ABSTRACT Objective This study aimed to develop hyaluronic acid-based retinoic acid-containing stimulation-sensitive vaginal nanoparticles and investigate the effects of newly developed vaginal nanoparticles on the regeneration of vaginal epithelial layers and aquaporin 3 expressions in the menopausal animal model. Methods The hyaluronic acid-based retinoic acid-loaded micelle nanoparticles were developed. Female Balb/C mice (8weeks, n=30) were divided into four groups: control, bilateral ovariectomy, HA-C18 vehicle administration group, and HA-C18RA administration group. After 4 weeks of treatment, the mouse vaginal tissue was removed, and the expressions of AQP3 were determined by Western blot and immunofluorescence staining. Results Three drug-loaded nanoparticles were synthesized. The content of retinoic acid supported in HA-C18 RA10, HA-C18 RA20, and HA-C18 RA 30 were 3.13%, 2.52%, and 16.67%, respectively, and the retinol acid encapsulation efficiency was 95.57%, 83.92%, and 93.24%, respectively. In the experimental group, serum estrogen levels were significantly reduced compared to the control group (p <0.05), and the vaginal mucosa epithelial layer was also significantly thinned. After 4 weeks of treatment, the vaginal mucosal epithelial layers were increased in the retinoic acid-loaded HAC18 administration group compared to the vehicle group. In addition, the expression of AQP3 was increased in the retinoic acid-carrying nanoparticle administration group. Conclusions The newly developed hyaluronic acid-based vaginal nanoparticles containing retinoic acid resulted in the recovery of the vaginal epithelial layers and also showed an increased expression of AQP3 in the vaginal epithelium. These results could contribute to developing functional vaginal lubricants/moisturizers for the treatment of women with vaginal dryness. Disclosure Work supported by industry: no.