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Cysteamine (Lynovex®), a novel mucoactive antimicrobial & antibiofilm agent for the treatment of cystic fibrosis.

Charrier C, Rodger C, Robertson J, Kowalczuk A, Shand N, Fraser-Pitt D, Mercer D, O'Neil D - Orphanet J Rare Dis (2014)

Bottom Line: Any successful therapeutic strategy designed to combat the respiratory pathology of this condition must address the altered lung physiology and recurrent, complex, polymicrobial infections and biofilms that affect the CF pulmonary tract.In all cases, the 'gold standard' therapeutic agents were employed as control/comparator compounds against which the efficacy of cysteamine was compared.The data we present here provides a platform for cysteamine's continued investigation as a novel treatment for this poorly served orphan disease.

View Article: PubMed Central - PubMed

Affiliation: NovaBiotics Ltd, Cruickshank Building, Craibstone, Aberdeen, AB21 9TR, UK. cedric.charrier@gmail.com.

ABSTRACT

Background: There remains a critical need for more effective, safe, long-term treatments for cystic fibrosis (CF). Any successful therapeutic strategy designed to combat the respiratory pathology of this condition must address the altered lung physiology and recurrent, complex, polymicrobial infections and biofilms that affect the CF pulmonary tract. Cysteamine is a potential solution to these unmet medical needs and is described here for the first time as (Lynovex®) a single therapy with the potential to deliver mucoactive, antibiofilm and antibacterial properties; both in oral and inhaled delivery modes. Cysteamine is already established in clinical practice for an unrelated orphan condition, cystinosis, and is therefore being repurposed (in oral form) for cystic fibrosis from a platform of over twenty years of safety data and clinical experience.

Methods: The antibacterial and antibiofilm attributes of cysteamine were determined against type strain and clinical isolates of CF relevant pathogens using CLSI standard and adapted microbiological methods and a BioFlux microfluidic system. Assays were performed in standard nutrient media conditions, minimal media, to mimic the low metabolic activity of microbes/persister cells in the CF respiratory tract and in artificial sputum medium. In vivo antibacterial activity was determined in acute murine lung infection/cysteamine nebulisation models. The mucolytic potential of cysteamine was assessed against DNA and mucin in vitro by semi-quantitative macro-rheology. In all cases, the 'gold standard' therapeutic agents were employed as control/comparator compounds against which the efficacy of cysteamine was compared.

Results: Cysteamine demonstrated at least comparable mucolytic activity to currently available mucoactive agents. Cysteamine was rapidly bactericidal against both metabolically active and persister cells of Pseudomonas aeruginosa and also emerging CF pathogens; its activity was not sensitive to high ionic concentrations characteristic of the CF lung. Cysteamine prevented the formation of, and disrupted established P. aeruginosa biofilms. Cysteamine was synergistic with conventional CF antibiotics; reversing antibiotic resistance/insensitivity in CF bacterial pathogens.

Conclusions: The novel mucolytic-antimicrobial activity of cysteamine (Lynovex®) provides potential for a much needed new therapeutic strategy in cystic fibrosis. The data we present here provides a platform for cysteamine's continued investigation as a novel treatment for this poorly served orphan disease.

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Related in: MedlinePlus

Determination of the minimum biofilm eradication concentration of cysteamine against establishedP. aeruginosaDSMZ1299 (A) andP. aeruginosaATCC27853 (B) biofilms. Cys – cysteamine. The optical density (492 nm) of crystal violet released from adherent cells within 24 h biofilms was used as an index of biofilm formation. A biofilm-positive phenotype was defined as OD ≥ 0.2. To compensate for background absorbance, OD readings of the sterile medium with both the fixative and dye were subtracted from all the experimental values. Experiments were performed in triplicate and results are presented as means. Error bars represent the standard error of the mean.
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Fig2: Determination of the minimum biofilm eradication concentration of cysteamine against establishedP. aeruginosaDSMZ1299 (A) andP. aeruginosaATCC27853 (B) biofilms. Cys – cysteamine. The optical density (492 nm) of crystal violet released from adherent cells within 24 h biofilms was used as an index of biofilm formation. A biofilm-positive phenotype was defined as OD ≥ 0.2. To compensate for background absorbance, OD readings of the sterile medium with both the fixative and dye were subtracted from all the experimental values. Experiments were performed in triplicate and results are presented as means. Error bars represent the standard error of the mean.

Mentions: Prevention of P. aeruginosa and other bacterial biofilms is a highly desirable characteristic for any new CF candidate therapy, but in the clinical setting, a truly effective CF treatment targeted to the chronic and recurrent respiratory infections associated with this condition should also be able to disrupt and even eradicate bacteria growing in established biofilms. As such, the biofilm eradication potential of cysteamine was assessed by determining its Minimum Biofilm Eradication Concentration (MBEC) against two P. aeruginosa biofilms (2a – DSMZ1299 & 2b – ATCC27853). As shown in Figure 2A-B, cysteamine was able to eradicate P. aeruginosa biofilms with an MBEC of 625 μg/ml (~2-3 times the MIC100; Table 1).Figure 2


Cysteamine (Lynovex®), a novel mucoactive antimicrobial & antibiofilm agent for the treatment of cystic fibrosis.

Charrier C, Rodger C, Robertson J, Kowalczuk A, Shand N, Fraser-Pitt D, Mercer D, O'Neil D - Orphanet J Rare Dis (2014)

Determination of the minimum biofilm eradication concentration of cysteamine against establishedP. aeruginosaDSMZ1299 (A) andP. aeruginosaATCC27853 (B) biofilms. Cys – cysteamine. The optical density (492 nm) of crystal violet released from adherent cells within 24 h biofilms was used as an index of biofilm formation. A biofilm-positive phenotype was defined as OD ≥ 0.2. To compensate for background absorbance, OD readings of the sterile medium with both the fixative and dye were subtracted from all the experimental values. Experiments were performed in triplicate and results are presented as means. Error bars represent the standard error of the mean.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4260250&req=5

Fig2: Determination of the minimum biofilm eradication concentration of cysteamine against establishedP. aeruginosaDSMZ1299 (A) andP. aeruginosaATCC27853 (B) biofilms. Cys – cysteamine. The optical density (492 nm) of crystal violet released from adherent cells within 24 h biofilms was used as an index of biofilm formation. A biofilm-positive phenotype was defined as OD ≥ 0.2. To compensate for background absorbance, OD readings of the sterile medium with both the fixative and dye were subtracted from all the experimental values. Experiments were performed in triplicate and results are presented as means. Error bars represent the standard error of the mean.
Mentions: Prevention of P. aeruginosa and other bacterial biofilms is a highly desirable characteristic for any new CF candidate therapy, but in the clinical setting, a truly effective CF treatment targeted to the chronic and recurrent respiratory infections associated with this condition should also be able to disrupt and even eradicate bacteria growing in established biofilms. As such, the biofilm eradication potential of cysteamine was assessed by determining its Minimum Biofilm Eradication Concentration (MBEC) against two P. aeruginosa biofilms (2a – DSMZ1299 & 2b – ATCC27853). As shown in Figure 2A-B, cysteamine was able to eradicate P. aeruginosa biofilms with an MBEC of 625 μg/ml (~2-3 times the MIC100; Table 1).Figure 2

Bottom Line: Any successful therapeutic strategy designed to combat the respiratory pathology of this condition must address the altered lung physiology and recurrent, complex, polymicrobial infections and biofilms that affect the CF pulmonary tract.In all cases, the 'gold standard' therapeutic agents were employed as control/comparator compounds against which the efficacy of cysteamine was compared.The data we present here provides a platform for cysteamine's continued investigation as a novel treatment for this poorly served orphan disease.

View Article: PubMed Central - PubMed

Affiliation: NovaBiotics Ltd, Cruickshank Building, Craibstone, Aberdeen, AB21 9TR, UK. cedric.charrier@gmail.com.

ABSTRACT

Background: There remains a critical need for more effective, safe, long-term treatments for cystic fibrosis (CF). Any successful therapeutic strategy designed to combat the respiratory pathology of this condition must address the altered lung physiology and recurrent, complex, polymicrobial infections and biofilms that affect the CF pulmonary tract. Cysteamine is a potential solution to these unmet medical needs and is described here for the first time as (Lynovex®) a single therapy with the potential to deliver mucoactive, antibiofilm and antibacterial properties; both in oral and inhaled delivery modes. Cysteamine is already established in clinical practice for an unrelated orphan condition, cystinosis, and is therefore being repurposed (in oral form) for cystic fibrosis from a platform of over twenty years of safety data and clinical experience.

Methods: The antibacterial and antibiofilm attributes of cysteamine were determined against type strain and clinical isolates of CF relevant pathogens using CLSI standard and adapted microbiological methods and a BioFlux microfluidic system. Assays were performed in standard nutrient media conditions, minimal media, to mimic the low metabolic activity of microbes/persister cells in the CF respiratory tract and in artificial sputum medium. In vivo antibacterial activity was determined in acute murine lung infection/cysteamine nebulisation models. The mucolytic potential of cysteamine was assessed against DNA and mucin in vitro by semi-quantitative macro-rheology. In all cases, the 'gold standard' therapeutic agents were employed as control/comparator compounds against which the efficacy of cysteamine was compared.

Results: Cysteamine demonstrated at least comparable mucolytic activity to currently available mucoactive agents. Cysteamine was rapidly bactericidal against both metabolically active and persister cells of Pseudomonas aeruginosa and also emerging CF pathogens; its activity was not sensitive to high ionic concentrations characteristic of the CF lung. Cysteamine prevented the formation of, and disrupted established P. aeruginosa biofilms. Cysteamine was synergistic with conventional CF antibiotics; reversing antibiotic resistance/insensitivity in CF bacterial pathogens.

Conclusions: The novel mucolytic-antimicrobial activity of cysteamine (Lynovex®) provides potential for a much needed new therapeutic strategy in cystic fibrosis. The data we present here provides a platform for cysteamine's continued investigation as a novel treatment for this poorly served orphan disease.

Show MeSH
Related in: MedlinePlus