Influence of corticosterone on growth, home-cage activity, wheel running, and aerobic capacity in house mice selectively bred for high voluntary wheel-running behavior

Although it has been established that some acute phase responses present differently depending on whether a virus or bacteria activates the innate immune system, it has not yet been established whether fever and sickness behaviors, such as anorexia and lethargy, present differently. We therefore investigated the effects of administering lipopolysaccharide (LPS) and polyinosinic : polycytidylic acid (poly I:C) on body temperature, food intake, body mass, and activity (cage activity and wheel running). Male Sprague–Dawley rats were randomly assigned to receive an intraperitoneal injection of one of LPS (75 µg/kg or 250 µg/kg), poly I:C (3000 µg/kg or 4000 µg/kg), or saline. Administration of LPS or poly I:C induced fever, anorexia, and lethargy. Although voluntary wheel running and cage activity were both significantly reduced after administration of LPS or poly I:C, they were not affected equally. Indeed voluntary wheel running was decreased on average by approximately 30% more than cage activity regardless of the dose or type of mimetic administered. Our results indicate that poly I:C is less effective at inducing anorexia, lethargy, and fever in rats than is LPS, and that avoidance of exercise in animals and humans during infection is likely to be a more prominent feature of illness than is avoidance of routine daily activity.

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Caffeine stimulates voluntary wheel running in mice without increasing aerobic capacity

Physiology & Behavior ◽

10.1016/j.physbeh.2016.12.031 ◽

2017 ◽

Vol 170 ◽

pp. 133-140 ◽

Cited By ~ 11

Author(s):

Gerald C. Claghorn ◽

Zoe Thompson ◽

Kristianna Wi ◽

Lindsay Van ◽

Theodore Garland

Keyword(s):

Aerobic Capacity ◽

Wheel Running ◽

Voluntary Wheel Running ◽

Voluntary Wheel

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Effects of voluntary activity and genetic selection on muscle metabolic capacities in house mice Mus domesticus

Journal of Applied Physiology ◽

10.1152/jappl.2000.89.4.1608 ◽

2000 ◽

Vol 89 (4) ◽

pp. 1608-1616 ◽

Cited By ~ 101

Author(s):

Philippe Houle-Leroy ◽

Theodore Garland ◽

John G. Swallow ◽

Helga Guderley

Keyword(s):

Lactate Dehydrogenase ◽

Citrate Synthase ◽

Wheel Running ◽

Genetic Selection ◽

House Mice ◽

Male Mice ◽

Selected Lines ◽

Voluntary Wheel Running ◽

Selection For ◽

Voluntary Wheel

Selective breeding is an important tool in behavioral genetics and evolutionary physiology, but it has rarely been applied to the study of exercise physiology. We are using artificial selection for increased wheel-running behavior to study the correlated evolution of locomotor activity and physiological determinants of exercise capacity in house mice. We studied enzyme activities and their response to voluntary wheel running in mixed hindlimb muscles of mice from generation 14, at which time individuals from selected lines ran more than twice as many revolutions per day as those from control (unselected) lines. Beginning at weaning and for 8 wk, we housed mice from each of four replicate selected lines and four replicate control lines with access to wheels that were free to rotate (wheel-access group) or locked (sedentary group). Among sedentary animals, mice from selected lines did not exhibit a general increase in aerobic capacities: no mitochondrial [except pyruvate dehydrogenase (PDH)] or glycolytic enzyme activity was significantly ( P < 0.05) higher than in control mice. Sedentary mice from the selected lines exhibited a trend for higher muscle aerobic capacities, as indicated by higher levels of mitochondrial (cytochrome- c oxidase, carnitine palmitoyltransferase, citrate synthase, and PDH) and glycolytic (hexokinase and phosphofructokinase) enzymes, with concomitant lower anaerobic capacities, as indicated by lactate dehydrogenase (especially in male mice). Consistent with previous studies of endurance training in rats via voluntary wheel running or forced treadmill exercise, cytochrome- c oxidase, citrate synthase, and carnitine palmitoyltransferase activity increased in the wheel-access groups for both genders; hexokinase also increased in both genders. Some enzymes showed gender-specific responses: PDH and lactate dehydrogenase increased in wheel-access male but not female mice, and glycogen phosphorylase decreased in female but not in male mice. Two-way analysis of covariance revealed significant interactions between line type and activity group; for several enzymes, activities showed greater changes in mice from selected lines, presumably because such mice ran more revolutions per day and at greater velocities. Thus genetic selection for increased voluntary wheel running did not reduce the capability of muscle aerobic capacity to respond to training.

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Effects Of Intrinsic Aerobic Capacity And Ovariectomy on Voluntary Wheel Running and Mid-brain Dopamine Signaling

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000487470.04975.2a ◽

2016 ◽

Vol 48 ◽

pp. 823

Author(s):

Young-Min Park ◽

Jill A. Kanaley ◽

Jaume Padilla ◽

Terese Zidon ◽

Rebecca Welly ◽

...

Keyword(s):

Aerobic Capacity ◽

Wheel Running ◽

Brain Dopamine ◽

Voluntary Wheel Running ◽

Dopamine Signaling ◽

Voluntary Wheel

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Artificial selection for high activity favors mighty mini-muscles in house mice

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00179.2002 ◽

2003 ◽

Vol 284 (2) ◽

pp. R433-R443 ◽

Cited By ~ 42

Author(s):

Philippe Houle-Leroy ◽

Helga Guderley ◽

John G. Swallow ◽

Theodore Garland

Keyword(s):

Muscle Mass ◽

Aerobic Capacity ◽

Citrate Synthase ◽

Wheel Running ◽

Relative Mass ◽

Selected Lines ◽

Voluntary Wheel Running ◽

Total Body Mass ◽

Selection For ◽

Voluntary Wheel

After 14 generations of selection for voluntary wheel running, mice from the four replicate selected lines ran, on average, twice as many revolutions per day as those from the four unselected control lines. To examine whether the selected lines followed distinct strategies in the correlated responses of the size and metabolic capacities of the hindlimb muscles, we examined mice from selected lines, housed for 8 wk in cages with access to running wheels that were either free to rotate (“wheel access” group) or locked (“sedentary”). Thirteen of twenty individuals in one selected line (line 6) and two of twenty in another (line 3) showed a marked reduction (∼50%) in total hindlimb muscle mass, consistent with the previously described expression of a small-muscle phenotype. Individuals with these “mini-muscles” were not significantly smaller in total body mass compared with line-mates with normal-sized muscles. Access to free wheels did not affect the relative mass of the mini-muscles, but did result in typical mammalian training effects for mitochondrial enzyme activities. Individuals with mini-muscles showed a higher mass-specific muscle aerobic capacity as revealed by the maximal in vitro rates of citrate synthase and cytochrome c oxidase. Moreover, these mice showed the highest activities of hexokinase and carnitine palmitoyl transferase. Females with mini-muscles showed the highest levels of phosphofructokinase, and males with mini-muscles the highest levels of pyruvate dehydrogenase. As shown by total muscle enzyme contents, the increase in mass-specific aerobic capacity almost completely compensated for the reduction caused by the “loss” of muscle mass. Moreover, the mini-muscle mice exhibited the lowest contents of lactate dehydrogenase and glycogen phosphorylase. Interestingly, metabolic capacities of mini-muscled mice resemble those of muscles after endurance training. Overall, our results demonstrate that during selection for voluntary wheel running, distinct adaptive paths that differentially exploit the genetic variation in morphological and physiological traits have been followed.

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Selection for high voluntary wheel-running increases speed and intermittency in house mice (Mus domesticus)

Journal of Experimental Biology ◽

10.1242/jeb.204.24.4311 ◽

2001 ◽

Vol 204 (24) ◽

pp. 4311-4320 ◽

Cited By ~ 1

Author(s):

I. Girard ◽

M. W. McAleer ◽

J. S. Rhodes ◽

T. Garland

Keyword(s):

Intermittent Exercise ◽

Wheel Running ◽

House Mice ◽

Mus Domesticus ◽

Selection Line ◽

Control Line ◽

Voluntary Wheel Running ◽

Continuous Exercise ◽

Selection For ◽

Voluntary Wheel

SUMMARY In nature, many animals use intermittent rather than continuous locomotion. In laboratory studies, intermittent exercise regimens have been shown to increase endurance compared with continuous exercise. We hypothesized that increased intermittency has evolved in lines of house mice (Mus domesticus) that have been selectively bred for high voluntary wheel-running (wheel diameter 1.12 m) activity. After 23 generations, female mice from four replicate selection lines ran 2.7 times more revolutions per day than individuals from four random-bred control lines. To measure instantaneous running speeds and to quantify intermittency, we videotaped mice (N=41) during a 5-min period of peak activity on night 6 of a 6-day exposure to wheels. Compared with controls (20 revs min–1 while actually running), selection-line females (41 revs min–1) ran significantly faster. These instantaneous speeds closely matched the computer-recorded speeds over the same 5-min period. Selection-line females also ran more intermittently, with shorter (10.0 s bout–1) and more frequent (7.8 bouts min–1) bouts than controls (16.8 s bout–1, 3.4 bouts min–1). Inter-bout pauses were also significantly shorter in selection-line (2.7 s) than in control-line (7.4 s) females. We hypothesize that intermittency of locomotion is a key feature allowing the increased wheel-running performance at high running speeds in selection-line mice.

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