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Chromogranin A-derived peptides are involved in innate immunity
R Aslam1, M Atindehou, T Lavaux
1University of Strasbourg, Biomatériaux et ingénierie Tissulaire, Inserm U977, Strasbourg, France.
Current Medicinal Chemistry
|July 28, 2012
Summary
New antimicrobial peptides derived from chromogranin A (CgA) show potential against bacteria and fungi. Bacterial proteases can degrade these peptides, but some forms remain active and can enhance antibiotic efficacy in innate defense.
Area of Science:
- Biochemistry
- Immunology
- Microbiology
Background:
- Endogenous antimicrobial peptides (AMPs) derived from chromogranin A (CgA) are secreted by various cells during stress.
- These CgA-derived AMPs exhibit antimicrobial activity against bacteria, fungi, and yeasts via pore formation and can activate neutrophils.
Purpose of the Study:
- To investigate the impact of bacterial proteases from Staphylococcus aureus and Salmonella enteritis on CgA-derived peptides.
- To evaluate the antimicrobial activities of these modified peptides and their potential synergistic effects with antibiotics.
Main Methods:
- Treatment of CgA-derived peptides with proteases from S. aureus (Glu-C) and S. enteritis.
- Assessment of antimicrobial activities of treated peptides against bacteria and fungi.
- Evaluation of synergistic effects of CgA-derived peptides with antibiotics.
Main Results:
- S. aureus V8 Glu-C protease degraded antibacterial activities of CgA-derived AMPs but generated new antifungal peptides.
- Antimicrobial peptides chromofungin, procatestatin, and catestatin were degraded by bacterial supernatants, while cateslytin remained active.
- Several CgA-derived peptides demonstrated synergistic antimicrobial effects with antibiotics against bacteria and fungi.
Conclusions:
- Bacterial proteases can modulate the antimicrobial activity of CgA-derived peptides, potentially altering their function.
- Cateslytin is a resistant and active form of catestatin against bacterial degradation.
- CgA-derived peptides hold promise as adjuncts to conventional antibiotics in combating microbial infections, highlighting their role in innate immunity.
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