Acta Biologica Hungarica

, Volume 68, Issue 3, pp 334–344 | Cite as

In Vitro Activity of Calcium Channel Blockers in Combination with Conventional Antifungal Agents Against Clinically Important Filamentous Fungi

  • Mónika Homa
  • Kinga Hegedűs
  • Ádám Fülöp
  • Vanessza Wolfárt
  • Shine Kadaikunnan
  • Jamal M. Khaled
  • Naiyf S. Alharbi
  • Csaba Vágvölgyi
  • László GalgóczyEmail author


Despite the current therapeutic options, filamentous fungal infections are associated with high mortality rate especially in immunocompromised patients. In order to find a new potential therapeutic approach, the in vitro inhibitory effect of two antiarrhythmic agents, diltiazem and verapamil hydrochloride were tested against different clinical isolates of ascomycetous and mucoralean filamentous fungi. The in vitro combinations of these non-antifungal drugs with azole and polyene antifungal agents were also examined. Susceptibility tests were carried out using the broth microdilution method according to the instructions of the Clinical and Laboratory Standards Institute document M38-A2. Checkerboard microdilution assay was used to assess the interactions between antifungal and non-antifungal drugs. Compared to antifungal agents, diltiazem and verapamil hydrochloride exerted a relatively low antifungal activity with high minimal inhibitory concentration values (853–2731 μg/ml). Although in combination they could increase the antifungal activity of amphotericin B, itraconazole and voriconazole. Indifferent and synergistic interactions were registered in 33 and 17 cases, respectively. Antagonistic interactions were not revealed between the investigated compounds. However, the observed high MICs suggest that these agents could not be considered as alternative systemic antifungal agents.


Diltiazem hydrochloride verapamil hydrochloride antifungal activity drug combinations synergistic interaction 


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  1. 1.
    Afeltra, J., Verweij, P. E. (2003) Antifungal activity of non-antifungal drugs. Eur. J. Clin. Microbiol. Infect. Dis. 22, 397–407.CrossRefGoogle Scholar
  2. 2.
    Afeltra, J., Vitale, R. G., Mouton, J. W., Verweij, P. E. (2004) Potent synergistic in vitro interaction between nonantimicrobial membrane-active compounds and itraconazole against clinical isolates of Aspergillus fumigatus resistant to itraconazole. Antimicrob. Agents Chemother. 48, 1335–1343.CrossRefGoogle Scholar
  3. 3.
    Ashbee, H. R., Barnes, R. A., Johnson, E. M., Richardson, M. D., Gorton, R., Hope, W. W. (2014) Therapeutic drug monitoring (TDM) of antifungal agents: guidelines from the British Society for Medical Mycology. J. Antimicrob. Chemother. 69, 1162–1176.CrossRefGoogle Scholar
  4. 4.
    Bulatova, N. R., Darwish, R. M. (2008) Effect of chemosensitizers on minimum inhibitory concentrations of fluconazole in Candida albicans. Med. Princ. Pract. 17, 117–121.CrossRefGoogle Scholar
  5. 5.
    CLSI (2008) Reference method for broth dilution antifungal susceptibility testing of filamentous fungi; Approved Standard–Second Edition. CLSI document M38-A2. Clinical and Laboratory Standards Institute, Wayne.Google Scholar
  6. 6.
    Crabol, Y., Lortholary, O. (2014) Invasive mold infections in solid organ transplant recipients. Scientifica 2014, 821969.CrossRefGoogle Scholar
  7. 7.
    Denning, D. W., Bromley, M. J. (2015) How to bolster the antifungal pipeline. Science 347, 1414–1416.CrossRefGoogle Scholar
  8. 8.
    Eliopoulos, G. M., Moellering, R. C. (1996) Antimicrobial combinations. In: Lorian, V. (ed.). Antibiotics In Laboratory Medicine. 4th Edition. The Williams and Wilkins Co., Baltimore, pp. 330–396.Google Scholar
  9. 9.
    GAFFI–Global Action Fund for Fungal Infections (2015) Report on activities for 2015. Available from: Accessed 21 July 2016.Google Scholar
  10. 10.
    Hamill, R. J. (2013) Amphotericin B formulations: a comparative review of efficacy and toxicity. Drugs 73, 919–934.CrossRefGoogle Scholar
  11. 11.
    Johnson, M. D., MacDougall, C., Ostrosky-Zeichner, L., Perfect, J. R., Rex, J. H. (2004) Combination antifungal therapy. Antimicrob. Agents Chemother. 48, 693–715.CrossRefGoogle Scholar
  12. 12.
    Khalaf, R. M., Jabir, H. B., Abbas, F. N. (2012) Investigation of the antifungal activity of some nonantifungal drugs in clinical isolates of otomycosis. J. Thi-Qar. Sci. 3, 31–39.Google Scholar
  13. 13.
    Köppel, C., Wagemann, A. (1991) Plasma level monitoring of D,L-verapamil and three of its metabolites by reversed-phase high-performance liquid chromatography. J. Chromatogr. 570, 229–234.CrossRefGoogle Scholar
  14. 14.
    Krajewska-Kułak, E., Niczyporuk, W. (1993) Effects of the combination of ketoconazole and calcium channel antagonists against Candida albicans in vitro. Arzneimittelforschung 43, 782–783.PubMedGoogle Scholar
  15. 15.
    Levy, R., Dana, R., Gold, B., Alkan, M., Schlaeffer, F. (1991) Influence of calcium channel blockers on polymorphonuclear and monocyte bactericidal and fungicidal activity. Isr. J. Med. Sci. 27, 301–306.PubMedGoogle Scholar
  16. 16.
    Lewis, R. E. (2008) What is the “therapeutic range” for voriconazole. Clin. Infect. Dis. 46, 212–214.CrossRefGoogle Scholar
  17. 17.
    Liu, S., Yue, L., Gu, W., Li, X., Zhang, L., Sun, S. (2016) Synergistic effect of fluconazole and calcium channel blockers against resistant Candida albicans. PLoS ONE 11, e0150859.Google Scholar
  18. 18.
    Low, C.-Y., Rotstein, C. (2011) Emerging fungal infections in immunocompromised patients. F1000 Med. Rep. 3, 14.CrossRefGoogle Scholar
  19. 19.
    Mendoza, L., Vilela, R., Voelz, K., Ibrahim, A. S., Voigt, K., Lee, S. C. (2014) Human fungal pathogens of Mucorales and Entomophthorales. Cold Spring Harb. Perspect. Med. 5, a019562.CrossRefGoogle Scholar
  20. 20.
    Methaneethorn, J., Chamnansua, M., Kaewdang, N., Lohitnavy, M. (2014) A pharmacokinetic drug–drug interaction model of simvastatin and verapamil in humans. Conf. Proc. IEEE Eng. Med. Biol. Soc. 2014, 5711–5714.PubMedGoogle Scholar
  21. 21.
    Monteiro, N., Silvestre, J., Gonçalves-Pereira, J., Tapadinhas, C., Mendes, V., Póvoa, P. (2013) Severe diltiazem poisoning treated with hyperinsulinaemia-euglycaemia and lipid emulsion. Case Rep. Crit. Care 2013, 138959.PubMedPubMedCentralGoogle Scholar
  22. 22.
    Odds, F. C. (2003) Synergy, antagonism, and what the chequerboard puts between them. J. Antimicrob. Chemother. 52, 1.CrossRefGoogle Scholar
  23. 23.
    Pina-Vaz, C., Rodrigues, A. G., Costa-de-Oliveira, S., Ricardo, E., Mårdh, P. A. (2005) Potent synergic effect between ibuprofen and azoles of Candida resulting from blockade of efflux pumps as determined by FUN-1 staining and flow cytometry. J. Antimicrob. Chemother. 56, 678–685.CrossRefGoogle Scholar
  24. 24.
    Praveen, R. J., Subramanyam, C. (1999) Requirement of Ca2+ for aflatoxin production: inhibitory effect of Ca2+ channel blockers on aflatoxin production by Aspergillus parasiticus NRRL 2999. Lett. Appl. Microbiol. 28, 85–88.CrossRefGoogle Scholar
  25. 25.
    Richards, D., Aronson, J., Reynolds, D. J., Coleman, J. (2011) Oxford Handbook of Practical Drug Therapy. 2nd Edition. Oxford University Press, Oxford.Google Scholar
  26. 26.
    Roilides, E., Dotis, J., Katragkou, A. (2007) Fusarium and Scedosporium: emerging fungal pathogens. In: Kavanagh, K. (ed.). New Insights in Medical Mycology. Springer, Dordrecht, pp. 267–285.CrossRefGoogle Scholar
  27. 27.
    Yu, Q., Ding, X., Xu, N., Cheng, X., Qian, K., Zhang, B., Xing, L., Li, M. (2013) In vitro activity of verapamil alone and in combination with fluconazole or tunicamycin against Candida albicans biofilms. Int. J. Antimicrob. Agents 41, 179–182.CrossRefGoogle Scholar
  28. 28.
    Yu, Q., Ding, X., Zhang, B., Xu, N., Jia, C., Mao, J., Zhang, B., Xing, L., Li, M. (2014) Inhibitory effect of verapamil on Candida albicans hyphal development, adhesion and gastrointestinal colonization. FEMS Yeast Res. 14, 633–641.CrossRefGoogle Scholar
  29. 29.
    Yu, Q., Xiao, C., Zhang, K., Jia, C., Ding, X., Zhang, B., Wang, Y., Li, M. (2014) The calcium channel blocker verapamil inhibits oxidative stress response in Candida albicans. Mycopathologia 177, 167–177.CrossRefGoogle Scholar

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© Akadémiai Kiadó, Budapest 2017

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Authors and Affiliations

  • Mónika Homa
    • 1
    • 2
  • Kinga Hegedűs
    • 3
  • Ádám Fülöp
    • 3
  • Vanessza Wolfárt
    • 3
  • Shine Kadaikunnan
    • 3
  • Jamal M. Khaled
    • 3
  • Naiyf S. Alharbi
    • 3
  • Csaba Vágvölgyi
    • 2
    • 3
  • László Galgóczy
    • 2
    Email author
  1. 1.MTA-SZTE “Lendület” Fungal Pathogenicity Mechanisms Research GroupSzegedHungary
  2. 2.Department of Microbiology, Faculty of Science and InformaticsUniversity of SzegedSzegedHungary
  3. 3.Department of Botany and Microbiology, College of ScienceKing Saud UniversityRiyadhSaudi Arabia

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