Efficacy of Chitin and Keratin Bioactive Fractions in Skin Inflammatory Processes Remission

The development of new therapies in the field of regenerative medicine is a priority area, which integrates, among other fields of research, the use of active molecules from extracts of natural origin with renewable potential. In this context, the biomedical applications of chitin from various natural sources (entomological, marine etc.), as well as those of keratin from leather waste, are included. The studies we initiated show the effectiveness of the Valke fraction of keratin, isolated from sheep's wool, and that of type L (from insects) and R (from crustaceans) chitin preparations, in modulating cellular processes specific to skin tissue degradation: IL6, IL8, IL1α cytokine-directed inflammation, angiogenic repairing processes (extracellular VEGF) and oxidative stress (oxygenated free radicals). The cellular response of keratinocytes from a HaCaT line under induced inflammation (LPS and TNFα) is manifested by increased intracellular levels of oxygenated free radicals, counteracted mainly by chitin. In case of bacterial infections simulated in vitro with LPS polysaccharide, the antiinflammatory effects induced by Valke keratin on IL6-directed signaling pathways (acute phase cytokine behavior) are noticeable. Moreover, the same effects are reflected through the inhibition of IL8, the chemokine responsible for neutrophil recruitment to the inflammatory site. Nonetheless chitin reduces the release of IL6, while strongly stimulating VEGF for "de novo" angiogenesis in the injured tissue. In addition, the pro-irritant cytokine IL1α is inhibited by chitin and keratin, which suggests a reduction in the epidermal irritant potential. The results guide the applications to several etiologies wound therapy. The studies were carried out within 5 PTE Project / 2020 – BIOTEHKER.