TB Research

Modulatory effects of verapamil in rifampicin activity against Mycobacterium tuberculosis

Caleffi-Ferracioli KR, Cardoso RF, de Souza JV, Murase LS, Canezin PH, Scodro RB, Ld Siqueira V, Pavan FR

Future microbiology · 2019-01

Abstract

Aim To evaluate modulatory effect of verapamil (VP) in rifampicin (RIF) activity and its effect in efflux pumps (EPs) transcript levels in Mycobacterium tuberculosis. Materials & methods RIF and VP minimal inhibitory concentration, combinatory effect and detection of mutations were determined in 16 isolates. EPs transcript levels were determined in four isolates by real-time PCR after exposure to drugs. Results VP showed good combinatory effect among RIF-resistant isolates. This effect was also observed in the relative transcript levels of EPs, mainly after 72 h of exposure, depending on the EP gene, genotype and the resistance profile of the isolate. Conclusion Additional regulatory mechanisms in the EP activities, as well as, interactions with other drug-specific resistance mechanisms need further investigation in M. tuberculosis.

MeSH terms

  • Humans
  • Mycobacterium tuberculosis
  • Tuberculosis, Multidrug-Resistant
  • Verapamil
  • Rifampin
  • Oxidoreductases
  • Catalase
  • DNA-Directed RNA Polymerases
  • Bacterial Proteins
  • Membrane Transport Proteins
  • Antitubercular Agents
  • Drug Therapy, Combination
  • Microbial Sensitivity Tests
  • Drug Resistance, Multiple, Bacterial
  • Gene Expression Regulation, Bacterial
  • Drug Synergism
  • Genotype
  • Mutation
  • Time Factors
  • Brazil