Plasticity of immunity in response to eating

Abstract

Following a meal, an animal can exhibit dramatic shifts in physiology and morphology, as well as a substantial increase in metabolic rate associated with the energetic costs of processing a meal (i.e. specific dynamic action, SDA). However, little is known about the effects of digestion on another important physiological and energetically costly trait: immune function. Thus, we tested two competing hypotheses.(1) Digesting animals up-regulate their immune systems ( putatively in response to the increased microbial exposure associated with ingested food). (2) Digesting animals down-regulate their immune systems ( presumably to allocate energy to the breakdown of food). We assayed innate immunity (lytic capacity and agglutination) in cornsnakes (Pantherophis guttatus) during and after meal digestion. Lytic capacity was higher in females, and (in support of our first hypothesis) agglutination was higher during absorption. Given its potential energetic cost, immune up-regulation may contribute to SDA.

The powerful immune system against powerful COVID-19: A hypothesis

“…Consuming foods with low specific dynamic action (SDA), as the energetic budget for consuming food, can potentially boost the immune system through improving the c-ATP. In 2016, Luoma et al demonstrated the effect of low-SDA meals in the up-regulation of the innate immune system in corn snakes (19). On the other hand, several studies have reported the positive effect of xanthine oxidoreductase inhibitors on c-ATP (6).…”

The Powerful Immune System Against Powerful COVID-19: A Hypothesis

“…Consuming foods with low specific dynamic action (SDA), as the energetic budget for consuming food, can potentially boost the immune system through improving the c-ATP. In 2016, Luoma et al demonstrated the effect of low-SDA meals in the up-regulation of the innate immune system in corn snakes (19). On the other hand, several studies have reported the positive effect of xanthine oxidoreductase inhibitors on c-ATP (6).…”

Eating increases oxidative damage in a reptile

“…The energetic costs of eating are well documented (Secor, 2008(Secor, , 2009), but digesting a meal may also have non-energetic costs, such as an up-regulation of the immune system (Luoma et al, 2016) or increased oxidative damage. Reactive oxygen species (ROS) are an inadvertent by-product of oxidative phosphorylation in the mitochondria during normal metabolic processes.…”