Volume 4 (2014): Issue 2 (December 2014)

Antimicrobial peptides are widely distributed in nature, and they are found in both Prokaryotes and Eukaryotes. Due to their characteristics, structure, functions and mode of action, they are divided into several groups. The only member of this family occurring in humans is cathelicidin - LL-37. It is produced as an inactive hCAP18 propeptide. The propeptide’s C-terminal fragment becomes a mature peptide subsequently to its enzymatic cleavage. LL-37 contains 37-amino acid residues, folds into α-helical structure and has amphipathic properties. Cathelicidin mechanism of action consists in the binding of LL-37 to the bacterial phospholipid membrane until a threshold concentration is reached, followed by the cytoplasm disintegration and leakage, and, finally, cell death. The peptide is expressed in several cells, for instance in the epithelial cells of testis, keratinocytes in the skin, leukocytes, monocytes, neutrophils, as well as T, B, and NK cells. Cathelicidin is a multifunctional molecule. It can serve as a mediator in inflammatory processes and/or as a natural antibiotic against Gram-negative and Gram-positive bacteria, viruses, and fungi. It is chemotactic for mononuclear cells, neutrophils, eosinophils, mast cells and T lymphocytes. LL-37 induces expression of chemokines, neutralises endotoxins, stimulates angiogenesis and apoptosis, as well as it boosts wound healing. Recent data have revealed an important role of LL-37 in the pathogenesis of systemic lupus erythematosus due to an impaired degradation of components in the neutrophil extracellular traps

Resveratrol is a natural organic compound, polyphenol, produced naturally by some plants in response to several harmful factors such as attack by pathogens, UV radiation, or increased oxidative stress. Many experiments suggest that it triggers mechanisms that counteract aging-related effects and plays a role in insulin resistance as well. It also possesses beneficial properties such as anti-cancer, anti-inflammatory, blood-sugar-lowering and cardiovascular effects. It is supposed to exhibit an interesting activity in neuroprotection - mainly through activation of sirtuins and counteraction in forming peptide aggregates. Still research is needed to evaluate exactly how resveratrol protects neurons, and to develop new, potential, therapeutic drugs