Anti-apoptotic effect of buffalo milk casein derived bioactive peptide by directing Nrf2 regulation in starving fibroblasts. (June 2020)

• Record Type: Journal Article
• Authors: Kumar, Naveen; Devi, Savita; Mada, Sanusi Bello; Reddi, Srinu; Kapila, Rajeev; Kapila, Suman
• Is Part Of: Food bioscience. Volume 35(2020)
• Publication Date: 2020-06
• Subjects: Buffalo milk β-casein -- Anti-apoptotic -- Pro-apoptotic -- Aging; Food -- Biotechnology -- Periodicals; Food -- Research -- Periodicals; Aliments -- Biotecnologia -- Revistes; Aliments -- Investigació -- Revistes; Food -- Biotechnology; Food -- Research; Revistes electròniques; Periodicals; 664.005
• DOI: 10.1016/j.fbio.2020.100566
• Languages: English
• ISSNs: 2212-4292

Abstract

Abstract: Starvation conditions cause cell injury or ulcers from reactive oxygen species generation and, ultimately, lead to cell death or apoptosis. Milk has many bioactive peptides with cytoprotective potential. One such peptide is the buffalo milk β-casein derived antioxidative peptide, VLPVPQK. It was found to have cytoprotective action during oxidative stress . However, the protective role of the peptide in natural aging induced apoptosis has not been studied. In the present study, the anti-apoptotic effect of the peptide was analyzed by establishing an in vitro model of skin fibroblast cells with serum starved conditions similar to aging. Cell survivability and cytotoxicity were measured using MTT and LDH assays, respectively. Cell death rate was determined using propidium iodide staining. In addition, gene level expression of anti-apoptotic markers' such as Nrf2, Keap-1, Bcl-2, Bax and HO-1 were analyzed using quantitative real time-PCR. While nuclear transmigration of Nrf2 at the protein level was analyzed using western blots. The peptide treatment led to inhibition of cell death as observed using PI, DCFH-DA staining and improvement in cell survival through the activation of transcription factor, Nrf2. The activation of Nrf2 stimulated the expression of cytoprotective signals from HO-1. Moreover, the peptide augmented the cellular protection by inhibiting the expression of the Nrf2 inhibitor (Keap1), pro-apoptotic markers (Bax) and stimulating anti-apoptotic (Bcl-2) gene expression. In addition, a pronounced reduction in the activity of the cell injury marker, LDH was observed. Hence, this study showed that the antioxidative peptide, VLPVPQK also showed an anti-apoptotic effect. Graphical abstract: Image 1 Highlights: VLPVPQK, bioactive peptide increases rat fibroblasts survival. The peptide acts via Nrf2 pathway. The peptide stimulates HO-1 and Bcl-2, but reduces the Bax and keap1.