Modulation of a Specific Pattern of microRNAs, Including miR-29a, miR-30a and miR-34a, in Cultured Human Skin Fibroblasts, in Response to the Application of a Biofunctional Ingredient that Protects against Cellular Senescence <i>in Vitro</i>

Abstract

Skin aging is a process of structural and compositional remodeling that can be manifested by wrinkling and sagging. Remarkably, the dermis plays a dominant role in the aging process. Recent studies suggest that microRNAs are implicated in the regulation of gene expression during aging. However, studies about age-related microRNAs and how they modulate skin aging remain limited. In the present work, a complex of hydrolyzed natural yeast proteins ( Saccharomyces cerevisiae ) and hydrolyzed natural soya bean was developed and showed the ability to modulate the expression of telomere - binding protein TRF 2, which is a key factor for telomere protection and to prevent cellular senescence in vitro and DNA damage. The aim of the study was to identify microRNAs specifically modulated after application of the ingredient complex to cultured fibroblasts, and their possible involvement in remodeling of the human extracellular matrix and fibroblast senescence. Consequently, human skin fibroblasts were cultured and treated with 1% of the ingredient complex for 48 h before analyzing microRNA modulation by RT-qPCR. The use of bioinformatics allowed us to predict the target genes for modulated microRNAs. Results show that the ingredient complex modulated a pattern of microRNAs including the down-regulation of miR-29a-3p, miR-30a-5p and miR-34a-5p, which are associated with fibroblast senescence and remodeling of the human dermal extracellular matrix. In conclusion, our results indicate that miR-29a-3p, miR-30a-5p and miR-34a-5p possibly represent key microRNAs that impact human fibroblast senescence and remodeling of the dermal extracellular matrix.