Metabolomics describes previously unknown toxicity mechanisms of isoniazid and rifampicin

Combrink, Monique; Loots, Du Toit; Preez, Ilse du

doi:10.1016/j.toxlet.2020.01.018

Cited by 43 publications

(21 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Indeed, rifampicin appeared the most toxic of all tested drugs as illustrated with over 90% cytotoxicity at 100-fold C max concentrations and complete abrogation of SFUs in the ELISpot assay. Mechanisms of increased cytotoxicity with rifampicin are uncertain but the formation of drug-antibody complexes, which binds to platelet membrane activating complement and increasing cell death has been proposed ( Combrink et al, 2020 ).…”

Section: Discussionmentioning

confidence: 99%

Dose Dependent Antimicrobial Cellular Cytotoxicity—Implications for ex vivo Diagnostics

Copaescu

Choshi²,

Pedretti³

et al. 2021

Front. Pharmacol.

View full text Add to dashboard Cite

Introduction:Ex vivo and in vitro diagnostics, such as interferon-γ (IFN-γ) release enzyme linked ImmunoSpot (ELISpot) and flow cytometry, are increasingly employed in the research and diagnostic setting for severe T-cell mediated hypersensitivity. Despite an increasing use of IFN-γ release ELISpot for drug causality assessment and utilization of a range of antimicrobial concentrations ex vivo, data regarding antimicrobial-associated cellular cytotoxicity and implications for assay performance remain scarcely described in the literature. Using the measurement of lactate dehydrogenase (LDH) and the 7-AAD cell viability staining, we aimed via an exploratory study, to determine the maximal antimicrobial concentrations required to preserve cell viability for commonly implicated antimicrobials in severe T-cell mediated hypersensitivity.Method: After an 18-h incubation of patient peripheral blood monocytes (PBMCs) and antimicrobials at varying drug concentrations, the cell cytotoxicity was measured in two ways. A colorimetric based assay that detects LDH activity and by flow cytometry using the 7-AAD cell viability staining. We used the PBMCs collected from three healthy control participants with no known history of adverse drug reaction and two patients with a rifampicin-associated drug reaction with eosinophilia and systemic symptoms (DRESS), confirmed on IFN-γ ELISpot assay. The PBMCs were stimulated for the investigated drugs at the previously published drug maximum concentration (Cmax), and concentrations 10- and 100-fold above.Results: In a human immunodeficiency virus (HIV) negative and a positive rifampicin-associated DRESS with positive ex vivo IFN-γ ELISpot assay, use of 10- and 100-fold Cmax drug concentrations decreased spot forming units/million cells by 32–100%, and this corresponded to cell cytotoxicity of more than 40 and 20% using an LDH assay and 7-AAD cell viability staining, respectively. The other antimicrobials (ceftriaxone, flucloxacillin, piperacillin/tazobactam, and isoniazid) tested in healthy controls showed similar dose-dependent increased cytotoxicity using the LDH assay, but cytotoxicity remained lower than 40% for all Cmax and 10-fold Cmax drug concentrations except flucloxacillin. All 100-fold Cmax concentrations resulted in cell death >40% (median 57%), except for isoniazid. 7-AAD cell viability staining also confirmed an increase in lymphocyte death in PBMCs incubated with 10-fold and 100-fold above Cmax for ceftriaxone, and flucloxacillin; however, piperacillin/tazobactam and isoniazid indicated no differences in percentages of viable lymphocytes across concentrations tested.Conclusion: The LDH cytotoxicity and 7-AAD cell viability staining techniques both demonstrate increased cell death corresponding to a loss in ELISpot sensitivity, with use of higher antimicrobial drug concentrations for ex vivo diagnostic IFN-γ ELISpot assays. For all the antimicrobials evaluated, the use of Cmax and 10-fold Cmax concentrations impacts cell viability and potentially affects ELISpot performance. These findings inform future approaches for ex vivo diagnostics such as IFN-γ release ELISpot.

show abstract

Section: Discussionmentioning

confidence: 99%

Dose Dependent Antimicrobial Cellular Cytotoxicity—Implications for ex vivo Diagnostics

Copaescu

Choshi²,

Pedretti³

et al. 2021

Front. Pharmacol.

View full text Add to dashboard Cite

show abstract

“…Mycothiol is also considered an important antioxidant required for balancing the cytosolic NAD + /NADH ratio [155]. In addition to the abovementioned inhibition of protein synthesis and enhanced fatty acid synthesis, altered energy metabolism has also consistently been identified in response to the first-line drugs INH [156], EMB [157], PZA [158], and RIF [159], supporting these results. In summary, the mycobacterial cell wall metabolism is visibly linked to the SOS response, which has frequently been proposed to cause resistance toward ciprofloxacin and challenge the otherwise impressive bactericidal activity of this drug [18,[160][161][162].…”

Section: Discussionmentioning

confidence: 80%

Elucidating the Antimycobacterial Mechanism of Action of Ciprofloxacin Using Metabolomics

et al. 2021

Self Cite

View full text Add to dashboard Cite

In the interest of developing more effective and safer anti-tuberculosis drugs, we used a GCxGC-TOF-MS metabolomics research approach to investigate and compare the metabolic profiles of Mtb in the presence and absence of ciprofloxacin. The metabolites that best describe the differences between the compared groups were identified as markers characterizing the changes induced by ciprofloxacin. Malic acid was ranked as the most significantly altered metabolite marker induced by ciprofloxacin, indicative of an inhibition of the tricarboxylic acid (TCA) and glyoxylate cycle of Mtb. The altered fatty acid, myo-inositol, and triacylglycerol metabolism seen in this group supports previous observations of ciprofloxacin action on the Mtb cell wall. Furthermore, the altered pentose phosphate intermediates, glycerol metabolism markers, glucose accumulation, as well as the reduction in the glucogenic amino acids specifically, indicate a flux toward DNA (as well as cell wall) repair, also supporting previous findings of DNA damage caused by ciprofloxacin. This study further provides insights useful for designing network whole-system strategies for the identification of possible modes of action of various drugs and possibly adaptations by Mtb resulting in resistance.

show abstract

“…Initial screening identified meropenem and rifampicin as potential antibiotics of choice to use in combination with polymyxin B. However, rifampicin displays non-linear pharmacokinetics and has a number of toxicity issues [31], whereas the broad-spectrum bactericidal activity, wide safety margin and clinical familiarity of meropenem [32] led us to choose meropenem as the most promising candidate for clinical translatability. Subsequently, we systematically investigated the effect of polymyxin B/meropenem combinations on bacterial killing of planktonic bacteria, inhibition of biofilm formation, and membrane integrity analysis of the treatment-resistant population.…”

Section: Discussionmentioning

confidence: 99%

Clinically Relevant Concentrations of Polymyxin B and Meropenem Synergistically Kill Multidrug-Resistant Pseudomonas aeruginosa and Minimize Biofilm Formation

Wickremasinghe

Azad

et al. 2021

Antibiotics

View full text Add to dashboard Cite

The emergence of antibiotic resistance has severely impaired the treatment of chronic respiratory infections caused by multidrug-resistant (MDR) Pseudomonas aeruginosa. Since the reintroduction of polymyxins as a last-line therapy against MDR Gram-negative bacteria, resistance to its monotherapy and recurrent infections continue to be reported and synergistic antibiotic combinations have been investigated. In this study, comprehensive in vitro microbiological evaluations including synergy panel screening, population analysis profiling, time-kill kinetics, anti-biofilm formation and membrane damage analysis studies were conducted to evaluate the combination of polymyxin B and meropenem against biofilm-producing, polymyxin-resistant MDR P. aeruginosa. Two phylogenetically unrelated MDR P. aeruginosa strains, FADDI-PA060 (MIC of polymyxin B [MICpolymyxin B], 64 mg/L; MICmeropenem, 64 mg/L) and FADDI-PA107 (MICpolymyxin B, 32 mg/L; MICmeropenem, 4 mg/L) were investigated. Genome sequencing identified 57 (FADDI-PA060) and 50 (FADDI-PA107) genes predicted to confer resistance to a variety of antimicrobials, as well as multiple virulence factors in each strain. The presence of resistance genes to a particular antibiotic class generally aligned with MIC results. For both strains, all monotherapies of polymyxin B failed with substantial regrowth and biofilm formation. The combination of polymyxin B (16 mg/L)/meropenem (16 mg/L) was most effective, enhancing initial bacterial killing of FADDI-PA060 by ~3 log10 CFU/mL, followed by a prolonged inhibition of regrowth for up to 24 h with a significant reduction in biofilm formation (* p < 0.05). Membrane integrity studies revealed a substantial increase in membrane depolarization and membrane permeability in the surviving cells. Against FADDI-PA107, planktonic and biofilm bacteria were completely eradicated. In summary, the combination of polymyxin B and meropenem demonstrated synergistic bacterial killing while reinstating the efficacy of two previously ineffective antibiotics against difficult-to-treat polymyxin-resistant MDR P. aeruginosa.

show abstract

Metabolomics describes previously unknown toxicity mechanisms of isoniazid and rifampicin

Cited by 43 publications

References 30 publications

Dose Dependent Antimicrobial Cellular Cytotoxicity—Implications for ex vivo Diagnostics

Dose Dependent Antimicrobial Cellular Cytotoxicity—Implications for ex vivo Diagnostics

Elucidating the Antimycobacterial Mechanism of Action of Ciprofloxacin Using Metabolomics

Clinically Relevant Concentrations of Polymyxin B and Meropenem Synergistically Kill Multidrug-Resistant Pseudomonas aeruginosa and Minimize Biofilm Formation

Contact Info

Product

Resources

About