Effects of early-life exposure to Western diet and voluntary exercise on adult activity levels, exercise physiology, and associated traits in selectively bred High Runner mice

DNA Methylation Analysis of Imprinted Genes in the Cortex and Hippocampus of Cross-Fostered Mice Selectively Bred for Increased Voluntary Wheel-Running

“…Because cross-fostering had no effect on adult exercise levels, future studies focusing on the methylation profiles of other tissues relevant to exercise physiology (e.g., skeletal muscle, heart, liver) are not likely to reveal important effects of cross-fostering on voluntary exercise behavior in these lines of mice. However, potential epigenetic effects induced by other early-life environmental factors, such as altered diet and/or exercise (Li et al 2013 ; Desai et al 2014a , 2014b ; Meek et al 2014 ; Acosta et al 2015 ; Hiramatsu et al 2017 ; Cadney et al 2021a , 2022 ), remain an important area of focus for additional study.…”

“…In addition, HR mice also demonstrate physiological and biochemical adaptations that are consistent with increased physical activity, including smaller body size, decreased fat composition, altered lipid profiles, and increased aerobic capacity (Swallow et al 1999 ; Malisch et al 2007 ; Acosta et al 2015 ). More recently, early-life studies on HR mice demonstrated differential responses to early-life factors of altered juvenile diet and exercise opportunity (Acosta et al 2015 ; Hiramatsu et al 2017 ; Cadney et al 2021a ; McNamara et al 2021 ).…”

Trade-Offs (and Constraints) in Organismal Biology

“…Thompson et al 2017). With respect to ability, the HR lines have higher endurance (Meek et al 2009) and maximal aerobic capacity (VO2max) (Cadney et al 2021) as measured during forced exercise, but have not suffered a general decline in maximal sprint speed (but see Dlugosz et al 2009). Changes in endocrine function, such as increased circulating concentrations of the "stress hormone" corticosterone in the HR lines, may contribute to changes in both their motivation and ability for sustained, aerobically supported running (Malisch et al 2007;Garland et al 2016;Wallace and Garland 2016).…”

Effects of early-life voluntary exercise and fructose on adult activity levels, body composition, aerobic capacity, and organ masses in mice bred for high voluntary wheel-running behavior

“…15,16 On the other hand, early-life exercise might counteract negative effects of fructose, as exercise during this period has been shown to have a number of positive effects on adult activity levels and caloric intake. [17][18][19] Although some early-life studies in rodent models have demonstrated effects of high-fructose intake on adult memory, 20,21 the microbiome, 22 thermoregulation, 23 and the development of arterial hypertension, 24 no previous study has examined effects on adult physical activity and related traits. Moreover, the possibility that early-life exercise might serve as a countermeasure to adverse effects of fructose overconsumption has not been studied (though physical activity in general is known to modulate the health effects of fructose 25 ).…”

“…[29][30][31] HR lines show changes in other relevant traits as well, including reduced body mass and body fat, increased heart mass, increased maximal aerobic capacity, altered levels of circulating corticosterone, adiponectin, and leptin, and an altered brain reward system. 17,30,[32][33][34][35][36] Previously, the HR lines (but not C lines) have been shown to increase wheel running while given Western diet continuously from weaning through adulthood. 27 However, in a separate study, when administration of Western diet was restricted to the period from weaning to sexual maturity (3 weeks), followed by 8 weeks of "washout" period, it increased adult wheel running in both HR and C lines.…”