Chitosan-Based Nanomedicine to Fight Genital Candida Infections: Chitosomes

Abstract

Vaginal infections are associated with high recurrence, which is often due to a lack of efficient treatment of complex vaginal infections comprised of several types of pathogens, especially fungi and bacteria. Chitosan, a mucoadhesive polymer with known antifungal effect, could offer a great improvement in vaginal therapy; the chitosan-based nanosystem could both provide antifungal effects and simultaneously deliver antibacterial drugs. We prepared chitosan-containing liposomes, chitosomes, where chitosan is both embedded in liposomes and surface-available as a coating layer. For antimicrobial activity, we entrapped metronidazole as a model drug. To prove that mucoadhesivness alone is not sufficient for successful delivery, we used Carbopol-containing liposomes as a control. All vesicles were characterized for their size, zeta potential, entrapment efficiency, and in vitro drug release. Chitosan-containing liposomes were able to assure the prolonged release of metronidazole. Their antifungal activity was evaluated in a C. albicans model; chitosan-containing liposomes exhibited a potent ability to inhibit the growth of C. albicans. The presence of chitosan was crucial for the system’s antifungal activity. The antifungal efficacy of chitosomes combined with antibacterial potential of the entrapped metronidazole could offer improved efficacy in the treatment of mixed/complex vaginal infections.

Utilizing Liposomal Quercetin and Gallic Acid in Localized Treatment of Vaginal Candida Infections

“…For this reason, the antifungal activity of polyphenol-containing liposomes and free polyphenols was evaluated against C. albicans ATCC 10231. Firstly, IC50 values were microscopically determined ( Table 5) and, as expected, plain-LP made only from SPC had no effect [26]. Although Q is known to possess antibacterial activity [14], neither free Q nor LP-Q were active in inhibiting Candida growth.…”

“…Sonication was used to obtain liposomes of the desired size [26]. The sonicator (Ultrasonic processor 500 W, Sigma-Aldrich, St. Louis, MO, USA) was set to 40% amplitude and ultrasonic Pharmaceutics 2020, 12, 9 4 of 21 irradiation for 4 cycles (30 s on/60 s off) was applied to liposomal dispersions.…”

“…The antifungal activity against Candida albicans ATCC 10231 was evaluated by broth microdilution following the method reported by Andersen et al [26]. C. albicans was grown aerobically in PDB Glu at 37 • C. After 24 h, Candida suspension was diluted in PDB Glu to reach a concentration of 4 × 10 5 cells/mL (determined by counting in a Bürker chamber).…”

The Antimicrobial Properties of Chitosan Can Be Tailored by Formulation

“…An optimal localized treatment of vaginal infections depends not only on the potency of the active ingredient/drug, but also on the physiochemical properties of the formulation; an ideal formulation can protect and enhance as well as act in synergy with antimicrobial to assure successful therapy [23]. Chitosan-based delivery systems exhibit strong mucoadhesive properties, an excellent safety profile and intrinsic antimicrobial activity of chitosan, which add to their attractiveness as pharmaceutical formulations, including those destined for vaginal delivery [4,17,24,25]. However, relatively little is known about the effects of the type of formulation on the antimicrobial performance of the formulation.…”

“…Considering the vagina as an administration site, chitosan is among the most promising materials. We have extensively studied chitosan-based delivery systems [2][3][4][5], both for skin and vaginal administration. To date, no consensus in the field has been reached considering the exact mechanisms of the antimicrobial actions of chitosan.…”