title: In Vitro Activity of Berberine Alone and in Combination with Antifungal Drugs Against Planktonic Forms and Biofilms of Trichosporon Asahii.
abstract: Trichosporon asahii (T. asahii) is an opportunistic pathogen that can cause life-threatening infections in immunocompromised patients, with high mortality rates up to 80% despite treated with antifungal drugs. The biofilms-forming ability of T. asahii on indwelling medical devices may account for the resistance to antifungal drugs. Berberine (BBR) has been demonstrated to have antifungal activity and synergistic effects in combination with antifungal drugs against pathogenic fungi. In the present study, the in vitro activities of BBR alone or combined with fluconazole (FLC), itraconazole (ITC), voriconazole (VRC), caspofungin (CAS) and amphotericin B (AMB) against planktonic forms and biofilms of 21 clinical T. asahii isolates were evaluated using checkerboard microdilution method and XTT reduction assay, respectively. The fractional inhibitory concentration index (FICI) was used to interpret drug interactions. BBR alone did not exhibit significant antifungal activities against both T. asahii planktonic cells (MICs, 32 → 128 μg/ml) and T. asahii biofilms (SMICs, >128 μg/ml). However, BBR exhibited synergistic effects against T. asahii planktonic cells in combination with AMB, FLC and CAS (FICI ≤ 0.5) and exhibited synergistic effects against T. asahii biofilms in combination with AMB and CAS (FICI ≤ 0.5). BBR/ITC and BBR/VRC combinations yielded mainly indifferent interactions against T. asahii planktonic cells. BBR/FLC, BBR/ITC and BBR/VRC combinations also yielded indifferent interactions against T. asahii biofilms. Our study highlights the therapeutic potential of BBR to be used as an antifungal synergist in combination with antifungal drugs against T. asahii infections, especially BBR/AMB combination. Further in vivo studies are needed to validate our findings.
authors.affiliation: Department of Dermatology, PLA Army General Hospital, 5 Nanmencang, Dongcheng District, Beijing, 100700, China.|Graduate School, Third Military Medical University, Chongqing, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Cong
authors.affiliation: Department of Dermatology, PLA Army General Hospital, 5 Nanmencang, Dongcheng District, Beijing, 100700, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liao
authors.affiliation: Department of Dermatology, PLA Army General Hospital, 5 Nanmencang, Dongcheng District, Beijing, 100700, China.
authors.forename: Suteng
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Dermatology, PLA Army General Hospital, 5 Nanmencang, Dongcheng District, Beijing, 100700, China. yangrya_l@sina.com.
authors.forename: Rongya
authors.initials: R
authors.lastname: Yang
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D001599:Berberine / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D004357:Drug Synergism; D005562:Formazans / Q000032:analysis; D006801:Humans; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects; D014250:Trichosporon / Q000187:drug effects* / Q000302:isolation & purification / Q000502:physiology
chemical_list: D000935:Antifungal Agents; D005562:Formazans; D001599:Berberine; C059088:1,5-bis(2-methoxy-4-nitro-5-sulfophenyl)-3-((phenylamino)carbonyl)formazan
keywords: Antifungal drugs; Berberine; Biofilms; Drug interaction; Trichosporon asahii