Nrf2 dependent antiaging effect of milkâ€derived bioactive peptide in old fibroblasts
Prolonged passaging of primary fibroblast cells totally shapes the natural biological phenomena and leads to the appearance of features related to senescence. As a result, it is a good natural tool to delineate the molecular mechanism of cellular aging. The present investigation revealed the antiaging effect of milkâ€derived novel bioactive peptide (VLPVPQK). The peptide played an important role in downregulating apoptosisâ€related markers in late passages of cultured fibroblast cells. The peptide treatment to aged fibroblasts caused enhancement in cell migration, DNA integrity, and decrease in the lipid peroxidation, reactive oxygen species, nitric oxide production as well as proâ€inflammatory cytokines, TNFâ€Î± and ILâ€6. Moreover, the peptide decreased the expression of apoptotic caspases, Bax, and senescenceâ€associated βâ€galactosidase (SAâ€Î²â€gal) proteins. The peptide pretreatment also enhanced the extracellular collagen protein and antiapoptotic, Bclâ€xL. In addition, the peptide treatment reversed the senescenceâ€related activity in fibroblasts by stimulating Nrf2 mediated antioxidative defense system and inhibiting the action of NFkB/p38MAPK signaling, similar to the commercially available inhibitor (SB203580) of p38MAPK. Thus, the peptide exhibits the antiaging effect in dermal fibroblast cells. Highlights 1. A novel bioactive peptide, VLPVPQK shows antiaging effect in prolonged serial passaged fibroblast cells. 2. The peptide causes activation and transmigration of Nrf2 for maintaining homeostasis. 3. The peptide rejuvenates the aged fibroblast cells by weakening the effects of the senescent associated secretory phenotype.4. The peptide alleviates the NFâ€kB/p38MAP kinase pathway in aged fibroblasts.