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

2003 ◽  
Vol 284 (2) ◽  
pp. R433-R443 ◽  
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.

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

2000 ◽  
Vol 89 (4) ◽  
pp. 1608-1616 ◽  
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.

Maximal oxygen consumption in relation to subordinate traits in lines of house mice selectively bred for high voluntary wheel running

2006 ◽  
Vol 101 (2) ◽  
pp. 477-485 ◽  
Author(s):  
Enrico L. Rezende ◽  
Fernando R. Gomes ◽  
Jessica L. Malisch ◽  
Mark A. Chappell ◽  
Theodore Garland
Keyword(s):  
Muscle Mass ◽  
Citrate Synthase ◽  
Wheel Running ◽  
Maximal Oxygen Consumption ◽  
Hemoglobin Concentration ◽  
Cellular Respiration ◽  
Voluntary Wheel Running ◽  
Hindlimb Muscle ◽  
The Individual ◽  
Voluntary Wheel

We studied relations between maximal O2 consumption (V̇o2 max) during forced exercise and subordinate traits associated with blood O2 transport and cellular respiration in four lines of mice selectively bred for high voluntary wheel running (S lines) and their four nonselected control (C) lines. Previously, we reported V̇o2 max of 59 females at three Po2 (hypoxia = 14% O2, normoxia = 21%, hyperoxia = 30%). Here, we test the hypothesis that variation in V̇o2 max can be explained, in part, by hemoglobin concentration and Po2 necessary to obtain 50% O2 saturation of Hb (an estimate of Hb affinity for O2) of the blood as well as citrate synthase activity and myoglobin concentration of ventricles and gastrocnemius muscle. Statistical analyses controlled for body mass, compared S and C lines, and also considered effects of the mini-muscle phenotype (present only in S lines and resulting from a Mendelian recessive allele), which reduces hindlimb muscle mass while increasing muscle mass-specific aerobic capacity. Although S lines had higher V̇o2 max than C, subordinate traits showed no statistical differences when the presence of the mini-muscle phenotype was controlled. However, subordinate traits did account for some of the individual variation in V̇o2 max. Ventricle size was a positive predictor of V̇o2 max at all three Po2. Blood Hb concentration was a positive predictor of V̇o2 max in S lines but a negative predictor in C lines, indicating that the physiological underpinnings of V̇o2 max have been altered by selective breeding. Mice with the mini-muscle phenotype had enlarged ventricles, with higher mass-specific citrate synthase activity and myoglobin concentration, which may account for their higher V̇o2 max in hypoxia.

scholarly journals The Effect of Voluntary Wheel Running on Muscle Mass, Mitochondrial Function and Oxidative Damage in Sod1???/???mice

2006 ◽  
Vol 38 (Suppl 1) ◽  
pp. S12
Author(s):  
Michael S. Lustgarten ◽  
Young C. Jang ◽  
Wook Song ◽  
Yuhong Liu ◽  
Anson Pierce ◽  
...  
Keyword(s):  
Oxidative Damage ◽  
Muscle Mass ◽  
Mitochondrial Function ◽  
Wheel Running ◽  
Voluntary Wheel Running ◽  
Voluntary Wheel

Caffeine stimulates voluntary wheel running in mice without increasing aerobic capacity

2017 ◽  
Vol 170 ◽  
pp. 133-140 ◽  
Author(s):  
Gerald C. Claghorn ◽  
Zoe Thompson ◽  
Kristianna Wi ◽  
Lindsay Van ◽  
Theodore Garland
Keyword(s):  
Aerobic Capacity ◽  
Wheel Running ◽  
Voluntary Wheel Running ◽  
Voluntary Wheel

Contractile abilities of normal and “mini” triceps surae muscles from mice (Mus domesticus) selectively bred for high voluntary wheel running

2005 ◽  
Vol 99 (4) ◽  
pp. 1308-1316 ◽  
Author(s):  
Douglas A. Syme ◽  
Kristin Evashuk ◽  
Benjamin Grintuch ◽  
Enrico L. Rezende ◽  
Theodore Garland
Keyword(s):  
Wheel Running ◽  
Fold Increase ◽  
Triceps Surae ◽  
Medial Gastrocnemius ◽  
Selected Lines ◽  
Voluntary Wheel Running ◽  
Running Activity ◽  
Gastrocnemius Muscles ◽  
Contractile Characteristics ◽  
Voluntary Wheel

As reported previously, artificial selection of house mice caused a 2.7-fold increase in voluntary wheel running of four replicate selected lines compared with four random-bred control lines. Two of the selected lines developed a high incidence of a small-muscle phenotype (“mini muscles”) in the plantar flexor group of the hindlimb, which apparently results from a simple Mendelian recessive allele. At generations 36–38, we measured wheel running and key contractile characteristics of soleus and medial gastrocnemius muscles from normal and mini muscles in mice from these selected lines. Mice with mini muscles ran faster and a greater distance per day than normal individuals but not longer. As expected, in mini-muscle mice the medial and lateral gastrocnemius muscles were ∼54 and 45% the mass of normal muscles, respectively, but the plantaris muscles were not different in mass and soleus muscles were actually 30% larger. In spite of the increased mass, contractile characteristics of the soleus were unchanged in any notable way between mini and normal mice. However, medial gastrocnemius muscles in mini mice were changed markedly toward a slower phenotype, having slower twitches; demonstrated a more curved force-velocity relationship; produced about half the mass-specific isotonic power, 20–50% of the mass-specific cyclic work and power (only 10–25% the absolute power if the loss in mass is considered); and fatigued at about half the rate of normal muscles. These changes would promote increased, aerobically supported running activity but may compromise activities that require high power, such as sprinting.

Exercise training, glucose transporters, and glucose transport in rat skeletal muscles

1992 ◽  
Vol 262 (1) ◽  
pp. C9-C14 ◽  
Author(s):  
K. J. Rodnick ◽  
E. J. Henriksen ◽  
D. E. James ◽  
J. O. Holloszy
Keyword(s):  
Glucose Transport ◽  
Endurance Exercise ◽  
Glucose Transporter ◽  
Citrate Synthase ◽  
Wheel Running ◽  
Fiber Type ◽  
Type I ◽  
Voluntary Wheel Running ◽  
Glut1 Protein ◽  
Voluntary Wheel

It was previously found that voluntary wheel running induces an increase in the insulin-sensitive glucose transporter, i.e., the GLUT4 isoform, in rat plantaris muscle (K. J. Rodnick, J. O. Holloszy, C. E. Mondon, and D. E. James. Diabetes 39: 1425-1429, 1990). The present study was undertaken to determine whether 1) the increase in muscle GLUT4 protein is associated with an increase in maximally stimulated glucose transport activity, 2) a conversion of type IIb to type IIa or type I muscle fibers plays a role in the increase in GLUT4 protein, and 3) an increase in the GLUT1 isoform is a component of the adaptation of muscle to endurance exercise. Five weeks of voluntary wheel running that resulted in a 33% increase in citrate synthase activity induced a 50% increase in GLUT4 protein in epitrochlearis muscles of female Sprague-Dawley rats. The rate of 2-deoxy-glucose transport maximally stimulated with insulin or insulin plus contractions was increased approximately 40% (P less than 0.05). There was no change in muscle fiber type composition, evaluated by myosin ATPase staining, in the epitrochlearis. There was also no change in GLUT1 protein concentration. We conclude that an increase in GLUT4, but not of GLUT1 protein, is a component of the adaptive response of muscle to endurance exercise and that the increase in GLUT4 protein is associated with an increased capacity for glucose transport.

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

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

scholarly journals Cardiac function is preserved following 4 weeks of voluntary wheel running in a rodent model of chronic kidney disease

2014 ◽  
Vol 117 (5) ◽  
pp. 482-491 ◽  
Author(s):  
James M. Kuczmarski ◽  
Christopher R. Martens ◽  
Jahyun Kim ◽  
Shannon L. Lennon-Edwards ◽  
David G. Edwards
Keyword(s):  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Cardiac Function ◽  
Citrate Synthase ◽  
Wheel Running ◽  
Left Ventricular ◽  
Cardiac Performance ◽  
Voluntary Wheel Running ◽  
Low Volume ◽  
Voluntary Wheel

The purpose of this investigation was to determine the effect of 4 wk of voluntary wheel running on cardiac performance in the 5/6 ablation-infarction (AI) rat model of chronic kidney disease (CKD). We hypothesized that voluntary wheel running would be effective in preserving cardiac function in AI. Male Sprague-Dawley rats were divided into three study groups: 1) sham, sedentary nondiseased control; 2) AI-SED, sedentary AI; and 3) AI-WR, wheel-running AI. Animals were maintained over a total period of 8 wk following AI and sham surgery. The 8-wk period included 4 wk of disease development followed by a 4-wk voluntary wheel-running intervention/sedentary control period. Cardiac performance was assessed using an isolated working heart preparation. Left ventricular (LV) tissue was used for biochemical tissue analysis. In addition, soleus muscle citrate synthase activity was measured. AI-WR rats performed a low volume of exercise, running an average of 13 ± 2 km, which resulted in citrate synthase activity not different from that in sham animals. Isolated AI-SED hearts demonstrated impaired cardiac performance at baseline and in response to preload/afterload manipulations. Conversely, cardiac function was preserved in AI-WR vs. sham hearts. LV nitrite + nitrate and expression of LV nitric oxide (NO) synthase isoforms 2 and 3 in AI-WR were not different from those of sham rats. In addition, LV H2O2 in AI-WR was similar to that of sham and associated with increased expression of LV superoxide-dismutase-2 and glutathione peroxidase-1/2. The findings of the current study suggest that a low-volume exercise intervention is sufficient to maintain cardiac performance in rats with CKD, potentially through a mechanism related to improved redox homeostasis and increased NO.

Sign in / Sign up

Export Citation Format

Share Document