Meeting Abstract

67.4  Jan. 7  Changes in antioxidant production during chronic caloric restriction may affect susceptibility to intestinal parasites. KRISTAN, Deborah M.*; CHEEKS, Chrystal; MANIBUSAN, Pierre T.; California State University, San Marcos; California State University, San Marcos; California State University, San Marcos dkristan@csusm.edu

Chronic caloric restriction (CR) produces many physiological benefits, including enhanced immune function. However, recent work indicates that, despite adequate immune function, CR can increase susceptibility to pathogen infection. We tested the effects of long-term CR on susceptibility of male and female laboratory mice ( Mus musculus, C57BL/6J) to the intestinal nematode Heligmosomoides bakeri. CR mice were fed 40% fewer calories than ad libitum (AL) mice, but had no micro- or macronutrient deficiencies. After six months of CR, mice were infected with H. bakeri. Both AL and CR mice showed similar amount of eosinophilia above levels of uninfected mice and CR mice had greater IgG1 than AL mice indicating adequate immune function of CR mice for the variables we examined. However, CR mice had more worms than AL mice and worms that resided in CR mice had greater egg output both in vivo and in vitro compared to worms from AL mice. A possible explanation for our data relates to the reactive oxygen species (ROS)/antioxidant pathway. Caloric restriction often decreases ROS production and has variable effects on antioxidants. This is important to our study because ROS are used by the mouse host against the parasite. Our preliminary data show decreased production of the superoxide dismutase antioxidant by the small intestine for CR compared to AL mice. A better understanding of the relationship between caloric restriction and the reactive oxygen species (ROS)/antioxidant pathway during parasite infection may have important implications for human health of persons living with low food availability but with high parasite prevalence.