Improvement of leukocyte functions in prematurely aging mice after five weeks of diet supplementation with polyphenol-rich cereals

ObjectiveWe investigated the beneficial effects of diet supplementation with two types of cereals naturally rich in polyphenolic compounds on several functions of peritoneal leukocytes from prematurely aging mice (PAM).MethodsTwo-hundred sixty healthy mice, 8 wk of age, were recruited and their behavioral responses were tested in a simple T-maze to identify PAM. Then the mice were fed a diet supplemented with 20% (wt/wt) of two different cereal fractions, named B (wheat germ) and C (buckwheat flour), rich in polyphenols (gallic acid, catechin, p-hydroxybenzoic acid, vanillic acid, p-coumaric acid, sinapic acid, ferulic acid, quercetin, and rutin), or a standard diet (controls) for 5 wk. Several parameters of innate (adherence to tissues, chemotaxis, phagocytosis, microbicidal capacity, and natural killer activity) and acquired immune (lymphoproliferation and interleukin-2 release) responses were measured.ResultsThe PAM control group showed worse immune functions (P < 0.001 to 0.05) compared with the non-PAM control group. The PAM group that received cereal B showed increases in phagocytosis (P < 0.01), microbicidal activity (P < 0.001 to 0.01), natural killer activity (P < 0.001) and lymphoproliferation in response to lipopolysaccharide (P < 0.01) and interleukin-2 release (P < 0.001), and the PAM group that received cereal C showed a similar pattern, with increases in macrophage chemotaxis (P < 0.01), phagocytosis (P < 0.01), microbicidal activity (P < 0.001 to 0.01), natural killer activity (P < 0.01), lymphoproliferative response to concanavalin A and lipopolysaccharide (P < 0.001), and interleukin-2 release (P < 0.001).ConclusionsDietary supplementation with polyphenol-rich cereals appears to have a protective effect on immune cell functions in mice with premature senescence. Thus, regular intake of these compounds could delay normal aging and improve quality of life.