Filmes de pullulan contendo nanocarreadores de óleo de romã: uma abordagem promissora para o tratamento de desordens cutâneas e vaginais

Abstract

The aim of this study was to develop Pullulan films (PUL) containing pomegranate seed oil nanocarriers for the cutaneous treatment of atopic dermatitis and vaginal application for the management of vulvovaginal candidiasis (VVC). PUL films were developed using the solvent casting method, and the selected plasticizers were sorbitol (6.5%) and PEG 400 (1.5%). The selected methodology for the preparation of Eudragit RS100 ® nanocapsules containing pomegranate seed oil (PSONC) was the interfacial deposition of the pre-formed polymer. For comparative purposes, nanoemulsions (PSONE) were prepared by the spontaneous emulsification method. The nanocarriers average diameter were 248 ± 16 nm for PSONE and 181 ± 6 nm for PSONC, the polydispersity index was below 0.2 and the zeta potential values were -25.63 ± 1.1 mV for PSONE and + 43.13 ± 0.7 mV for PSONC. The pH remained in the acid range, with values of 6.77 ± 0.27 and 5.31 ± 0.17, respectively. The films demonstrated high occlusive properties (57.6 ± 0.8%, 66.3 ± 0.8%) and their irritation potential were evaluated by the chorio-allantoic membrane test (HET-CAM), which confirmed the formulations biocompatibility. The biological performance of the films was tested in an animal model of atopic dermatitis induced by dinitrochlorobenzene (DNCB) in Balb / c female mice, with 30 days of duration (CEEA: 23357-2018). The animals were induced with DNCB, and, on the fourteenth day of the protocol, treated in the groups: naive; untreated DNCB-induced; pure pomegranate seed oil; vehicle film; pomegranate oil nanoemulsion film (PSONEF); pomegranate oil nanocapsule film (PSONCF) and hydrocortisone positive control. Induction and treatments were performed on the dorsal skin. On the last day of the protocol, the skin lesions levels were assessed and the mechanical hypersensitivity test (Von-frey filament) was performed. Afterwards, the animals were euthanized and oxidative stress and inflammatory parameters such as myeloperoxidase (MPO), reactive species (RS) and superoxide dismutase (SOD) were assessed. The results demonstrated that the formulation containing pomegranate seed oil nanocapsules (PSONCF) promoted the modulation of the inflammatory response and oxidative stress, improving the skin lesions and reducing nociception. Thus, clotrimazole (CTZ) was incorporated into the best formulation (PSONCF) as a model drug to treat VVC. The incorporation of CTZ nanocapsules to the PUL film increased its homogeneity and maintained its stability for 120 days. In vitro release and permeation tests were also evaluated using the dialysis bag and the Franz cell methodology, where the nanoencapsulation promoted CTZ controlled release (60% of the drug in 24). Furthermore, the mucoadhesive properties of the nanocapsule suspension were evaluated by the mucin interaction method, where the inversion of the zeta potential (+32.00 ± 1.56 mV to -5.20 ± 0.07 mV) and the increase in the mean diameter (171 ± 0.4 nm to 747 ± 79) displayed the bioadhesive potential of the formulation. In addition, the mucoadhesive strength and disintegration time of the films were assessed, demonstrating that the film is mucoadhesive and rapidly disintegrating (10 min), considered compatible and safe for vaginal application. Finally, the agar diffusion test was carried out in order to observe the antifungal activity of the formulation against Candida albicans. The nanoencapsulation, as well as the incorporation in the polymeric film was able to keep the in vitro antifungal activity of CTZ against Candida albicans. In conclusion, the developed films were considered suitable and promising for cutaneous and vaginal application in the treatment of atopic dermatitis and vulvovaginal candidiasis.