Radioprotective Effect of Whey Hydrolysate Peptides against γ-Radiation-Induced Oxidative Stress in BALB/c Mice

Radiation therapy is widely used in the treatment of tumor diseases, but it can also cause serious damage to the body, so it is necessary to find effective nutritional supplements. The main purpose of this study is to evaluate the protective effect of whey hydrolysate peptides (WHPs) against 60Coγ radiation damage in mice and explore the mechanism. BALB/c mice were given WHPs by oral gavage administration for 14 days. Then, some mice underwent a 30-day survival test after 8 Gy radiation, and other mice received 3.5 Gy radiation to analyze the changes in body weight, hematology and bone marrow DNA after three and 14 days. In addition, through further analysis of the level of oxidative stress and intestinal barrier function, the possible mechanism of the radioprotective effect of WHPs was explored. The study found WHPs can prolong survival time, restore body weight, and increase the number of peripheral blood white blood cells and bone marrow DNA content in irradiated mice. In addition, WHPs can significantly improve the antioxidant capacity, inhibit pro-inflammatory cytokines and protect the intestinal barrier. These results indicate that WHPs have a certain radioprotective effect in mice, and the main mechanism is related to reducing oxidative damage.

Description of biologically active protein hydrolysates of whey and colostrum

Antioxidant, antimutagenic and antigenic properties of partial hydrolysates of whey and colostrum obtained using bacterial endopeptidase (alcalase) have been investigated. It was found that the depth of proteolysis, qualitative and quantitative composition of protein component of samples determined the level of their antiradical and antimutagenic activity. According to SDS-electrophoresis whey hydrolysate contains cleaved allergen proteins, whereas colostrum hydrolysate possesses a high molecular weight fraction (>10 kDa) of partially digested immunoglobulins. Proteolysis of β-lactoglobulin, which has a high allergenic potential, is confirmed by results of immunoprecipitation reaction. In accordance with the ORAC method antioxidant action of hydrolysed whey and colostrum increased by 2.8 and 5.0 times, respectively. Antimutagenic effect for whey hydrolysate was 15.7–49.2 % when tested on the strain Salmonella typhimurium TA 98 and 18.8–52.1 % for strain TA 100. It exceeded values of colostrum hydrolysate. Samples of whey and colostrum hypoallergenic hydrolysates with confirmed antioxidant and antimutagenic properties have been obtained.