Changes of Gene Expression in Candida albicans Isolates from Vaginal Infections by Effects of Zinc Oxide Nanoparticles and Fluconazole

Background: There are serious challenges of drug resistance in Candida albicans infection. Therefore, it is essential to identify new antifungal agents against resistant species to effectively treat patients affected by these species. Objectives: The present study aimed to study how zinc oxide nanoparticles (ZnO-NPs) and fluconazole affected the genes encoding resistance to fluconazole (i.e., CDR2 and ERG11) and those encoding adhesins (i.e., ALS1 and HWP1) in C. albicans isolates. Methods: In this descriptive-analytic study, samples of 120 patients with vaginitis were obtained using sterile swabs. After the identification of C. albicans strains, the fluconazole-resistant candida isolates were treated with various sub-minimum inhibitory concentrations of ZnO-NPs, fluconazole, and a combination of ZnO-NPs and fluconazole. Then, the effects of ZnO-NPs and fluconazole on the expression levels of ALS1, HWP1, CDR2, and ERG11 genes were evaluated by real-time polymerase chain reaction. Results: In this study, 50 out (41.6%) of 120 species with C. albicans were isolated, and 13 (26%) of 50 species were resistant to fluconazole. The expression analysis of fluconazole-resistant C. albicans strains showed that the expression of HWP1 and ALS1 genes was decreased by 2.84 and 1.62 times (P < 0.05), respectively. Nevertheless, the expression of CDR2 increased 1.42 - fold after the treatment with fluconazole. The expression of ERG11, CDR2, HWP1, and ALS1 in isolates treated with the combination of ZnO-NPs and fluconazole was downregulated by 2.1, 5.9, 3, and 5.5 times, respectively, compared to that of the control group. Conclusions: Based on the results, ZnO-NPs are helpful for the treatment of vaginitis-related C. albicans isolates in combination with fluconazole.

Molecular Characterization and Antifungal Susceptibility of Candida Species Isolated From Vulvovaginitis in Jahrom City, South of Iran

Background: Vulvovaginal candidiasis (VVC) is a significant health issue due to Candida spp. Although Candida albicans is considered a major causative agent of vaginal candidiasis, non-albicans species have increased during previous decades. Objectives: This research aimed at molecular identification and assessing antifungal susceptibility of VVC isolated Candida spp. Methods: A professional physician examined two hundred and ninety-five suspected females with vaginitis. The specimens were collected by sterile cotton swabs. Swabs were inoculated on Sabouraud dextrose agar plates and then incubated for 48 - 72 hours at 35°C. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect all Candida species. Broth microdilution, according to the M27-A3 and M27-S4 CLSI documents, were employed for determining the antifungal susceptibility tests of caspofungin (CAS), voriconazole (VRC), itraconazole (ITC), fluconazole (FLU), clotrimazole (CLO), ketoconazole (KTO), amphotericin B (AMB), and nystatin (NYS). Results: A total of 295 females suspected of vulvovaginal candidiasis were examined. The culture results were positive in 50.5% (149 of 295) of specimens. According to molecular identification techniques, C. albicans 133/149 (89.2%), C. glabrata 8/149 (5.4%), and C. kefyr 2/149 (1.4%) were the main species. A mixed infection of C. albicans and C. glabrata 6/149 (4 %) was detected. The geometric mean values to all Candida strains were in increasing order as the following: CAS, 0.075 µg/mL; VRC, 0.091 µg/mL; ITC, 0.15 µg/mL; AMB, 0.22 µg/mL; CLO, 0.23 µg/mL; KTO, 0.28 µg/mL; NYS, 0.88 µg/mL; FLU, 1.48 µg/mL. Further, the MIC ranges of all Candida isolates to the tested antifungal agents were in increasing order as follows: CAS: 0.031 - 0.25 µg/mL, KTO and ITC: 0.031 - 2 µg/mL, VRC: 0.031 - 4 µg/mL, CLO and AMB: 0.031 - 8 µg/mL, NYS: 0.06 - 4 µg/mL, and FLU: 0.12 - 128 µg/mL. Conclusions: We reported 1 (7.2 %) C. glabrata isolate resistance to FLU and 2 (14.3%) C. glabrata isolates susceptible-dose-dependent (SDD) to CAS. We also reported 6 (4.5%), 5 (3.8%), and 2 (1.5%) C. albicans resistance to ITC, FLU, and AMB, respectively, but 100% C. albicans susceptible to CAS and VRC.

Molecular Investigation of Etiologic Agents Causing Vulvovaginal Candidiasis

Background: Vulvovaginal candidiasis (VVC) is an ordinary infection caused by Candida species. Meanwhile, a shift towards non-albicans Candida (NAC) species has been detected in VVC patients. Objectives: This study aimed at molecular identification of Candida isolates, causing VVC. Methods: Vaginal secretion samples of 320 non-pregnant vaginitis patients at Shahid Akbar-Abadi Obstetrics and Gynecology Hospital in Tehran (Iran) were collected. Samples were evaluated using mycological and molecular approaches. Vaginitis isolates were analyzed with the PCR using NL1 and NL4 primers, and the D1/D2 region of the large-subunit rRNA gene was amplified and sequenced. Results: In total, 100 Candida isolates were identified from VVC and recurrent vulvovaginal candidiasis (RVVC). Candida albicans was the most frequent (51%), followed by C. glabrata (36%), C. krusei (Pichia kudriavzevii) (8%), and C. kefyr (Kluyveromyces marxianus) (5%). 51 and 49% of isolates had C. albicans and NAC, respectively. Conclusions: Candida albicans and C. glabrata were the most common agents of vulvovaginal candidiasis. NAC spp. (49%) was found as an important agent associated with VVC.