1384 Innovative palmitoyl tetrapeptide-20: A promising solution to fight grey hair

Abstract

Premature canitie and greying hair pigmentation are phenomenons directly linked to a melanin lack in the hair bulb but also to the accumulation of hydrogen peroxide (H2O2) in hair follicles. To counteract these processes, we have developed a biomimetic peptide of the α-MSH (palmitoyl tetrapeptide-20), enables to promote in vitro, ex vivo and in vivo hair pigmentation and reduce hair greying process. In vitro studies revealed the peptide capacity to increase melanin synthesis by 39% in human melanocytes and melanosome transfer to keratinocytes by 50%. In HFDP cells, the peptide was also able to decrease significantly by 30% intracellular H2O2 level. Ex vivo, after 7 days of peptide application, the peptide increased by 35% the hair bulb pigmentation. This result was confirmed by immunohistochemistry and fluorescent immunostaining of pigmentation and oxidative markers on human micro dissected hairs. Protein expressions of Melan-A, TRP1, TRP2 were increased whereas the expression of ASIP protein and catalase was decreased. The clinical study conducted during 3 months with a daily application of a peptide lotion at 2% on fifteen men volunteers suffering from canitie showed a significant decrease in L factor by 5.3. Interestingly, this result was also confirmed by gene and protein expressions directly analyzed on volunteers hair. In summary, we have proven that our palmitoyl tetrapeptide-20 fights against hair greying, protects follicular melanocytes activity and could be the new hair care innovative peptide able to promote hair pigmentation and counteract the greying hair process.