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Modeling Energy Dynamics in Mice with Skeletal Muscle Hypertrophy Fed High Calorie Diets.

Bond ND, Guo J, Hall KD, McPherron AC - Int. J. Biol. Sci. (2016)

Bottom Line: Retrospective and prospective studies show that lean mass or strength is positively associated with metabolic health.Their leanness is often attributed to higher energy expenditure in the face of normal food intake.We have previously developed a computational model to estimate energy output, fat oxidation and respiratory quotient from food intake and body composition measurements to more accurately account for changes in body composition in rodents over time.

View Article: PubMed Central - PubMed

Affiliation: 1. Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892 USA;

ABSTRACT
Retrospective and prospective studies show that lean mass or strength is positively associated with metabolic health. Mice deficient in myostatin, a growth factor that negatively regulates skeletal muscle mass, have increased muscle and body weights and are resistant to diet-induced obesity. Their leanness is often attributed to higher energy expenditure in the face of normal food intake. However, even obese animals have an increase in energy expenditure compared to normal weight animals suggesting this is an incomplete explanation. We have previously developed a computational model to estimate energy output, fat oxidation and respiratory quotient from food intake and body composition measurements to more accurately account for changes in body composition in rodents over time. Here we use this approach to understand the dynamic changes in energy output, intake, fat oxidation and respiratory quotient in muscular mice carrying a dominant negative activin receptor IIB expressed specifically in muscle. We found that muscular mice had higher food intake and higher energy output when fed either chow or a high-fat diet for 15 weeks compared to WT mice. Transgenic mice also matched their rate of fat oxidation to the rate of fat consumed better than WT mice. Surprisingly, when given a choice between high-fat diet and Ensure® drink, transgenic mice consumed relatively more calories from Ensure® than from the high-fat diet despite similar caloric intake to WT mice. When switching back and forth between diets, transgenic mice adjusted their intake more rapidly than WT to restore normal caloric intake. Our results show that mice with myostatin inhibition in muscle are better at adjusting energy intake and output on diets of different macronutrient composition than WT mice to maintain energy balance and resist weight gain.

No MeSH data available.


Related in: MedlinePlus

Feeding regimens. (A) Muscle-DN mice were fed chow, HF diet or HF diet plus Ensure® for 15 weeks. (B) MSTN KO mice were fed chow for 21 days, HF diet for 14 days, then returned to chow for 14 days. Body composition was determined weekly starting at time 0 for all mice. Chow, NIH-31 diet; HF, 59% kcal from fat, Bio-Serv.
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Figure 1: Feeding regimens. (A) Muscle-DN mice were fed chow, HF diet or HF diet plus Ensure® for 15 weeks. (B) MSTN KO mice were fed chow for 21 days, HF diet for 14 days, then returned to chow for 14 days. Body composition was determined weekly starting at time 0 for all mice. Chow, NIH-31 diet; HF, 59% kcal from fat, Bio-Serv.

Mentions: For computational analysis in Muscle-DN mice and WT littermates, male mice were placed on standard chow, 59% HF diet, or 59% HF diet plus Ensure® in chambers for 15 weeks starting at ~9 weeks of age (Figure 1A, n = 5-8 per group). Because mice came of age at different times, start and end times were staggered so that data was collected over more than 15 weeks to complete groups. One Muscle-DN mouse fed HF diet stopped eating in week 14 due to malocclusion and was euthanized. For MSTN KO mice and WT littermates, food intake in chambers was measured daily for 7 weeks in female mice age 17-26 weeks (Figure 1B, n = 8-9 per group). The feeding schedule was standard chow for 21 days, then 59% HF diet alone for 14 days, and then standard chow for 14 days.


Modeling Energy Dynamics in Mice with Skeletal Muscle Hypertrophy Fed High Calorie Diets.

Bond ND, Guo J, Hall KD, McPherron AC - Int. J. Biol. Sci. (2016)

Feeding regimens. (A) Muscle-DN mice were fed chow, HF diet or HF diet plus Ensure® for 15 weeks. (B) MSTN KO mice were fed chow for 21 days, HF diet for 14 days, then returned to chow for 14 days. Body composition was determined weekly starting at time 0 for all mice. Chow, NIH-31 diet; HF, 59% kcal from fat, Bio-Serv.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4829546&req=5

Figure 1: Feeding regimens. (A) Muscle-DN mice were fed chow, HF diet or HF diet plus Ensure® for 15 weeks. (B) MSTN KO mice were fed chow for 21 days, HF diet for 14 days, then returned to chow for 14 days. Body composition was determined weekly starting at time 0 for all mice. Chow, NIH-31 diet; HF, 59% kcal from fat, Bio-Serv.
Mentions: For computational analysis in Muscle-DN mice and WT littermates, male mice were placed on standard chow, 59% HF diet, or 59% HF diet plus Ensure® in chambers for 15 weeks starting at ~9 weeks of age (Figure 1A, n = 5-8 per group). Because mice came of age at different times, start and end times were staggered so that data was collected over more than 15 weeks to complete groups. One Muscle-DN mouse fed HF diet stopped eating in week 14 due to malocclusion and was euthanized. For MSTN KO mice and WT littermates, food intake in chambers was measured daily for 7 weeks in female mice age 17-26 weeks (Figure 1B, n = 8-9 per group). The feeding schedule was standard chow for 21 days, then 59% HF diet alone for 14 days, and then standard chow for 14 days.

Bottom Line: Retrospective and prospective studies show that lean mass or strength is positively associated with metabolic health.Their leanness is often attributed to higher energy expenditure in the face of normal food intake.We have previously developed a computational model to estimate energy output, fat oxidation and respiratory quotient from food intake and body composition measurements to more accurately account for changes in body composition in rodents over time.

View Article: PubMed Central - PubMed

Affiliation: 1. Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892 USA;

ABSTRACT
Retrospective and prospective studies show that lean mass or strength is positively associated with metabolic health. Mice deficient in myostatin, a growth factor that negatively regulates skeletal muscle mass, have increased muscle and body weights and are resistant to diet-induced obesity. Their leanness is often attributed to higher energy expenditure in the face of normal food intake. However, even obese animals have an increase in energy expenditure compared to normal weight animals suggesting this is an incomplete explanation. We have previously developed a computational model to estimate energy output, fat oxidation and respiratory quotient from food intake and body composition measurements to more accurately account for changes in body composition in rodents over time. Here we use this approach to understand the dynamic changes in energy output, intake, fat oxidation and respiratory quotient in muscular mice carrying a dominant negative activin receptor IIB expressed specifically in muscle. We found that muscular mice had higher food intake and higher energy output when fed either chow or a high-fat diet for 15 weeks compared to WT mice. Transgenic mice also matched their rate of fat oxidation to the rate of fat consumed better than WT mice. Surprisingly, when given a choice between high-fat diet and Ensure® drink, transgenic mice consumed relatively more calories from Ensure® than from the high-fat diet despite similar caloric intake to WT mice. When switching back and forth between diets, transgenic mice adjusted their intake more rapidly than WT to restore normal caloric intake. Our results show that mice with myostatin inhibition in muscle are better at adjusting energy intake and output on diets of different macronutrient composition than WT mice to maintain energy balance and resist weight gain.

No MeSH data available.


Related in: MedlinePlus