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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

Antibacterial efficacy of cysteamine and tobramycin onP. aeruginosaincubated under nutrient-limiting and Nutrient replete conditions. The MIC100 of P. aeruginosa PAO1, P. aeruginosa NH57388A and P. aeruginosa NH57388B were determined according to standard CLSI conditions for – A) nutrient replete media (MH broth), whereas – B) M9 minimal medium was substituted for MH broth to provide nutrient-limiting conditions. The graphs (A & B) show data for P. aeruginosa PAO1. The table shows the mean MIC of triplicate samples from triplicate experiments. Error bars represent the Standard Error of the Mean. P. aeruginosa NH57388A is a mucoid strain. P. aeruginosa NH57388B is a non-mucoid strain. * - P. aeruginosa NH57388B is tobramycin resistant.
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Fig6: Antibacterial efficacy of cysteamine and tobramycin onP. aeruginosaincubated under nutrient-limiting and Nutrient replete conditions. The MIC100 of P. aeruginosa PAO1, P. aeruginosa NH57388A and P. aeruginosa NH57388B were determined according to standard CLSI conditions for – A) nutrient replete media (MH broth), whereas – B) M9 minimal medium was substituted for MH broth to provide nutrient-limiting conditions. The graphs (A & B) show data for P. aeruginosa PAO1. The table shows the mean MIC of triplicate samples from triplicate experiments. Error bars represent the Standard Error of the Mean. P. aeruginosa NH57388A is a mucoid strain. P. aeruginosa NH57388B is a non-mucoid strain. * - P. aeruginosa NH57388B is tobramycin resistant.

Mentions: Bacteria in the CF lung grow in biofilms under nutrient-limited conditions [25], so the antibacterial efficacy of cysteamine was assessed under nutrient limiting (M9 minimal medium) and excess nutrient (MH broth) conditions. Under the more physiologically relevant, nutrient-limiting assay conditions (Figure 6), the MIC100 of cysteamine against P. aeruginosa was reduced by 4–8 fold, whereas the MIC100 of tobramycin was unchanged, suggesting a cysteamine mechanism of action that is not dependent on metabolic activity. This data suggests that not only is cysteamine a biofilm prevention and disrupting agent (Figures 1 and 2), but is also directly antibacterial against CF pathogens (Table 1) and importantly, demonstrates improved efficacy under nutrient limited conditions such as within the CF lung environment.Figure 6


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)

Antibacterial efficacy of cysteamine and tobramycin onP. aeruginosaincubated under nutrient-limiting and Nutrient replete conditions. The MIC100 of P. aeruginosa PAO1, P. aeruginosa NH57388A and P. aeruginosa NH57388B were determined according to standard CLSI conditions for – A) nutrient replete media (MH broth), whereas – B) M9 minimal medium was substituted for MH broth to provide nutrient-limiting conditions. The graphs (A & B) show data for P. aeruginosa PAO1. The table shows the mean MIC of triplicate samples from triplicate experiments. Error bars represent the Standard Error of the Mean. P. aeruginosa NH57388A is a mucoid strain. P. aeruginosa NH57388B is a non-mucoid strain. * - P. aeruginosa NH57388B is tobramycin resistant.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Fig6: Antibacterial efficacy of cysteamine and tobramycin onP. aeruginosaincubated under nutrient-limiting and Nutrient replete conditions. The MIC100 of P. aeruginosa PAO1, P. aeruginosa NH57388A and P. aeruginosa NH57388B were determined according to standard CLSI conditions for – A) nutrient replete media (MH broth), whereas – B) M9 minimal medium was substituted for MH broth to provide nutrient-limiting conditions. The graphs (A & B) show data for P. aeruginosa PAO1. The table shows the mean MIC of triplicate samples from triplicate experiments. Error bars represent the Standard Error of the Mean. P. aeruginosa NH57388A is a mucoid strain. P. aeruginosa NH57388B is a non-mucoid strain. * - P. aeruginosa NH57388B is tobramycin resistant.
Mentions: Bacteria in the CF lung grow in biofilms under nutrient-limited conditions [25], so the antibacterial efficacy of cysteamine was assessed under nutrient limiting (M9 minimal medium) and excess nutrient (MH broth) conditions. Under the more physiologically relevant, nutrient-limiting assay conditions (Figure 6), the MIC100 of cysteamine against P. aeruginosa was reduced by 4–8 fold, whereas the MIC100 of tobramycin was unchanged, suggesting a cysteamine mechanism of action that is not dependent on metabolic activity. This data suggests that not only is cysteamine a biofilm prevention and disrupting agent (Figures 1 and 2), but is also directly antibacterial against CF pathogens (Table 1) and importantly, demonstrates improved efficacy under nutrient limited conditions such as within the CF lung environment.Figure 6

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