Peptides Reverse Multiple Cellular Aging Markers in Skin Fibroblasts In Vitro

Skin fibroblasts are crucial cells responsible for maintaining the structural integrity and elasticity of the skin by producing collagen and other extracellular matrix components. During cellular aging (senescence), these fibroblasts exhibit reduced proliferation, impaired regenerative capacity, increased programmed cell death (apoptosis), and excessive degradation of the extracellular matrix, contributing to visible signs of skin aging. Despite extensive research, effective interventions that can comprehensively reverse these age-related cellular dysfunctions in fibroblasts remain elusive.

The findings demonstrated that all four peptides—KE, KED, AED, and AEDG—exerted significant anti-aging effects on the cultured fibroblasts. Specifically, all studied peptides inhibited the synthesis of MMP-9, an enzyme whose levels typically increase during the aging of skin fibroblasts, indicating a reduction in detrimental extracellular matrix degradation. Concurrently, these peptides enhanced the expression of Ki-67 and CD98hc, both of which are normally less intensively synthesized during cellular aging, suggesting improved proliferation and regenerative capacity. Furthermore, peptides AED and AEDG specifically suppressed caspase-dependent apoptosis, a process that typically increases in aging cell cultures. The peptides KE, KED, AED, and AEDG collectively demonstrated a multifaceted anti-aging effect on skin fibroblasts, simultaneously improving cellular proliferation and regeneration markers while significantly reducing detrimental extracellular matrix degradation and programmed cell death.