Proliferation of Propionibacterium acnes (P. acnes) is one of the main pathogenetic mechanisms of acne. Antimicrobial peptides with low-drug resistance and nonresidual are potential anti-acne agents. In this study, two antimicrobial peptides named temporin-1Dra and moronecidin were synthesized and tested their antimicrobial activity against P. acnes in vitro and in vivo. These two peptides inhibited the growth of Escherichia coli, Staphylococcus aureus, Candida albicans, and P. acnes. The minimal inhibitory concentrations (MICs) of temporin-1Dra and moronecidin to P. acnes were 30 and 10 μM, respectively. Both peptides exhibited strong resistance to heat and pH, but no obvious cytotoxicity to HaCaT cells. They also displayed persistent antimicrobial activities in the microbial challenge test. In the P. acnes-induced inflammation mouse model, moronecidin significantly decreased the ear swelling thickness in a concentration-dependent manner. At the 14th day after injection, 20 μg/day moronecidin reduced the ear swelling thickness to 46.15 ± 5.23% compared with the normal cream group. Tissue staining showed that moronecidin effectively reduced abscess and thickness of the dermis layer. Our results indicate that the antimicrobial peptide moronecidin could be developed as a potential natural anti-acne agent in the cosmetics or pharmaceutical industries.
Keywords: Propionibacterium acnes; acne; antimicrobial peptides; moronecidin; temporin-1Dra.
© 2020 European Peptide Society and John Wiley & Sons, Ltd.