Polylysine dendrigraft is able to differentially impact Cutibacterium acnes strains preventing acneic skin

With a view to reducing the impact of Cutibacterium acnes (C. acnes) on acne vulgaris, it now appears interesting to modify the balance between acneic and non-acneic strains of C. acnes using moderate approach. In the present study, we identified that a G2 dendrigraft of lysine dendrimer (G2 dendrimer) was able to modify membrane fluidity and biofilm formation of a C. acnes acneic strain (RT5), whereas it appeared no or less active on a C. acnes non-acneic strain (RT6). Moreover, skin ex vivo data indicated that the G2 is able to decrease inflammation (IL1α and TLR-2) and improve skin desquamation after of C. acnes acneic strains colonization. Then, in vivo data confirmed, after C. acnes quantification by metagenomic analysis that the G2 cream after 28 days of treatment was able to increase the diversity of C. acnes strains versus placebo cream. The data also showed a modification of the balance expression between C. acnes phylotype IA1 and phylotype II abundances. Taken together, the results confirm the interest of using soft compounds in cosmetic product for modifying phylotype abundances and diversity of C. acnes strains could be a new strategy for prevent acne vulgaris outbreak.