Dietary effect on immunological energetics in mice

Abstract

Defense against natural aggressors, such as bacterial infections, requires both energy and an immune-cellular response. However, the question as to how these two components are interconnected in small endotherms by means of the host diet remains only poorly understood. Here, we tested in laboratory mice whether dietary proteins and carbohydrates can modulate the interplay between energy expenditure, food intake and the innate and adaptive immune response when confronting a bacterial challenge (Bacillus Calmette-Guérin, BCG). We observed that mice fed with a high protein diet (HP) developed a better immune response associated to increased numbers of circulating monocytes. In addition, HP diet directly influenced the peripheral blood proportions of both T and B lymphocytes even before the BCG challenge. Interestingly, animals that developed this type of immune response after BCG challenge showed an increased rate of metabolism and food consumption before being challenged. Thus, HP diet induced in non-challenged animals a similar energy expenditure and food intake described by BCG-treated mice. These data suggest that a high amount of proteins in diet can modify the energetic and nutrient dynamic in the host causing a better immune reaction against a microbial challenge.

Feeding Immunity: Physiological and Behavioral Responses to Infection and Resource Limitation

“…While this investment could partially close the gap in protein acquisition between treatments, consumption would need to be 400% higher in the LP treatment to achieve similar protein levels to individuals on the HP diet. However, dietary protein does not affect host metabolic rate ( 16 ), so maintenance costs (Figure 1 ) are likely similar between treatments. Insects were also present in the enclosures and diet metabarcoding tools could be used in future studies to examine if, and to what degree, lab mice are able to utilize them as a food source.…”

Nutritional ecology and ecological immunology in degus: Does early nutrition affect the postnatal development of the immune function?

“…Our findings add to this growing body of research by suggesting that the effect of diet depends on the variables analyzed; however, we cannot abandon the possibility of the effect of a more extreme diet on the immune system development. Other studies have reported that diets with a greater difference in the amount of proteins (~45%) resulted in effects on the immune response in adult mice (Martel et al, 2014). On the other hand, it is essential to study the relationship of fiber content of diet and the variables analyzed here.…”

“…Dietary quality is an essential factor that influences the maintenance and functioning of the immune system of animals (Catalán et al, 2011; De Coster et al, 2011; Klasing, 2007; Venesky et al, 2012). For instance, the amount of dietary protein has been related to the magnitude of the immune response of some endothermic species (Bounous et al, 1983; Jennings et al, 1992; Li et al, 2007; Martel et al, 2014). Specifically, diets with low‐protein content are related to suppression of the immune response (Jennings et al, 1992; Li et al, 2007; Venesky et al, 2012).…”