Oral intake of degalactosylated whey protein increases peripheral blood telomere length in young and aged mice

In order to elucidate novel actions of degalactosylated whey protein (D-WP) in comparison with intact whey protein (WP), the effects of oral intake of D-WP on peripheral blood telomere length and telomerase were examined in young and aged mice. In young mice, peripheral blood telomere length was significantly elongated following oral intake of D-WP for 4 weeks. mRNA expression of both telomerase reverse transcriptase (TERT) and telomerase RNA component (TERC) was significantly increased in the peripheral blood following oral intake of D-WP for 4 weeks. In aged mice, peripheral blood telomere length was significantly decreased as compared with that of young mice, and significantly restored to the level of young mice drinking water by the oral intake of D-WP for 4 weeks. The mRNA expression of peripheral blood TERT and TERC mRNA in aged mice significantly decreased as compared with the level in young mice drinking water, and was significantly restored to the level of expression of young mice drinking water by oral intake of D-WP for 4 weeks. These results suggest that D-WP, but not WP, potently increases peripheral blood telomere length accompanied by increased mRNA expression of TERT and TERC in both young and aged mice.