Augmentation of Mouse Immune Functions by Dietary Restriction: An Investigation up to 1 Year of Age

Abstract

Mice fed a 40% restricted diet until 1 year of age showed a 35% drop in body weight and markedly lower weights in the central lymphoid organs such as spleen and thymus than those of unrestricted mice. In contrast, the percentage of splenic Thy 1.2⁺ T cells was dramatically increased by dietary restriction. Splenic Ly 1⁺ T cells were also increased in the restricted mice. Spleen cells of the restricted mice revealed significantly higher responses not only in macrophage (MP)-dependent responses such as concanavalin A response and mixed-lymphocyte reaction but also in MP-independent T cell responses to recombinant interleukin 2 even at 1 year of age. These results strongly suggest that dietary restriction causes an enrichment of Thy 1.2⁺ T cells in spleen and augments the functions of T cells in mice.

High-dose, short-term exposure of mice to perfluorooctanesulfonate (PFOS) or perfluorooctanoate (PFOA) affects the number of circulating neutrophils differently, but enhances the inflammatory responses of macrophages to lipopolysaccharide (LPS) in a similar fashion

“…Severe caloric restriction is known to substantially reduce the numbers, chemotaxis and phagocytic activity of neutrophils in the bone marrow pool, as well as in the peripheral blood of rats (Suda et al, 1976;Ogawa et al, 1985;Garcia and Barbieri, 1986;Levin et al, 1993;Slapnickova and Berger, 2002). In addition, moderate caloric restriction is known to reduce thymic and splenic weight and cellularity, as well as the numbers of CD4 + CD8 + thymocytes and splenic B-lymphocytes (Hishinuma et al, 1990;Poetschke et al, 2000;Savino, 2002;Martin et al, 2008) and to alter the nucleolar structure and function in lymphocytes (Berger et al, 2005). Together, these observations indicate that while moderate food restriction affects primarily lymphocytes, severe food restriction can exert adverse effects on both lymphocytes and neutrophils.…”

The atrophy and changes in the cellular compositions of the thymus and spleen observed in mice subjected to short-term exposure to perfluorooctanesulfonate are high-dose phenomena mediated in part by peroxisome proliferator-activated receptor-alpha (PPARα)

“…Short-term caloric restriction is known to reduce thymic and splenic weight and cellularity, as well as the numbers of CD4 + CD8 + thymocytes and splenic B-lymphocytes (Hishinuma et al, 1990;Poetschke et al, 2000;Savino, 2002;Martin et al, 2008). Furthermore, it has been reported recently that decreased food intake can be mediated by the activation of PPAR␣ (Asakawa et al, 2008).…”

The effects of food restriction on some biochemical parameters and certain bacterial groups in the cecum in Sprague Dawley rats

“…Moderate food restriction also activates immune parameters. T-cell function augments in food-restricted mice (32), and foodrestricted mice have a strong antititumor immunity (33). Moreover, acute stress causes mucin release from rat colon via activated neurons and mast cells by CRF (34).…”