Antioxidant Properties of Buffalo-Milk Dairy Products: A β-Lg Peptide Released after Gastrointestinal Digestion of Buffalo Ricotta Cheese Reduces Oxidative Stress in Intestinal Epithelial Cells

• Main Authors: Manuela Giovanna Basilicata, Giacomo Pepe, Simona Adesso, Carmine Ostacolo, Marina Sala, Eduardo Sommella, Maria Carmina Scala, Antonella Messore, Giuseppina Autore, Stefania Marzocco, Pietro Campiglia
• Format: Article
• Language: English
• Published: MDPI AG 2018-07-01
• Series: International Journal of Molecular Sciences
• Subjects: buffalo-milk dairy products; in vitro gastrointestinal digestion; solid-phase synthesis (SPPS); intestinal epithelial cells (IEC-6); reactive oxygen species (ROS); NAD(P)H: quinone oxidoreductase 1 (NQO1); heme oxygenase 1 (HO-1); superoxide dismutase (SOD); nuclear factor erythroid 2-related factor 2 (Nrf2)
• Online Access: http://www.mdpi.com/1422-0067/19/7/1955

Redox signaling regulates different gastrointestinal (G.I.) epithelium functions. At the intestinal level, the loss of redox homeostasis in intestinal epithelial cells (IECs) is responsible for the pathogenesis and development of a wide diversity of G.I. disorders. Thus, the manipulation of oxidative stress in IECs could represent an important pharmacological target for different diseases. In this study, peptides released from in vitro gastro intestinal digestion of different buffalo-milk commercial dairy products were identified and evaluated for their bioactive properties. In particular, six G.I. digests of dairy products were tested in a model of oxidative stress for IECs. Among them, buffalo ricotta cheese was the most active and the presence of an abundant β-lactoglobulin peptide (YVEELKPTPEGDL, f:60-72) was also revealed. The antioxidant potential of the identified peptide was also evaluated in a model of hydrogen peroxide (H2O2)-induced oxidative stress in the IEC-6 cell line. The peptide was able to reduce ROS release, while, on the other hand, it increased nuclear factor (erythroid-derived 2)-like 2 (Nrf2) activation and the expression of antioxidant cytoprotective factors, such as heme oxygenase 1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO1), and superoxide dismutase (SOD). These results indicate that buffalo ricotta cheese-isolated peptide could have potential in the treatment of some gastrointestinal disorders.