Thermal conditions experienced during differentiation affect metabolic and contractile phenotypes of mouse myotubes

Central pathways regulate metabolic responses to cold in endotherms to maintain relatively stable internal core body temperatures. However, peripheral muscles routinely experience temperatures lower than core body temperature, so that it would be advantageous for peripheral tissues to respond to temperature changes independently from core body temperature regulation. Early developmental conditions can influence offspring phenotypes, and here we tested whether developing muscle can compensate locally for the effects of cold exposure independently from central regulation. Muscle myotubes originate from undifferentiated myoblasts that are laid down during embryogenesis. We show that in a murine myoblast cell line (C2C12), cold exposure (32°C) increased myoblast metabolic flux compared with 37°C control conditions. Importantly, myotubes that differentiated at 32°C compensated for the thermodynamic effects of low temperature by increasing metabolic rates, ATP production, and glycolytic flux. Myotube responses were also modulated by the temperatures experienced by “parent” myoblasts. Myotubes that differentiated under cold exposure increased activity of the AMP-stimulated protein kinase (AMPK), which may mediate metabolic changes in response cold exposure. Moreover, cold exposure shifted myosin heavy chains from slow to fast, presumably to overcome slower contractile speeds resulting from low temperatures. Adjusting thermal sensitivities locally in peripheral tissues complements central thermoregulation and permits animals to maintain function in cold environments. Muscle also plays a major metabolic role in adults, so that developmental responses to cold are likely to influence energy expenditure later in life.

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Interleukin-6 is important for regulation of core body temperature during long-term cold exposure in mice

Biomedical Reports ◽

10.3892/br.2018.1118 ◽

2018 ◽

Cited By ~ 2

Author(s):

Emil Egecioglu ◽

Fredrik Anesten ◽

Erik Sch�le ◽

Vilborg Palsdottir

Keyword(s):

Body Temperature ◽

Cold Exposure ◽

Interleukin 6 ◽

Core Body Temperature ◽

Core Body

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Infrared thermal imaging as a method to study thermogenesis in the neonatal lamb

Animal Production Science ◽

10.1071/an14301 ◽

2014 ◽

Vol 54 (9) ◽

pp. 1497 ◽

Cited By ~ 5

Author(s):

S. A. McCoard ◽

H. V. Henderson ◽

F. W. Knol ◽

S. K. Dowling ◽

J. R. Webster

Keyword(s):

Body Temperature ◽

Heat Loss ◽

Cold Exposure ◽

Thermal Imaging ◽

Core Body Temperature ◽

Recovery Period ◽

Exposure Period ◽

Skin Surface ◽

Infrared Thermal Imaging ◽

Core Body

The combination of heat generation and reducing heat loss from the skin surface is important for maintaining core body temperature in a neonate. Thermogenesis studies traditionally focus on measurement of core body temperature but not the contribution of radiated heat loss at the skin surface. This study aimed to evaluate the utility of using thermal imaging to measure radiated heat loss in newborn lambs. Continuous thermal images of newborn lambs were captured for 30 min each during the baseline (11−18°C), cold-exposure (0°C) and recovery (11−18°C) periods by using an infrared camera. Core body temperature measured by rectal thermometer was also recorded at the end of each period. In all, 7 of the 10 lambs evaluated had reduced rectal temperatures (0.4−1°C) between the baseline and recovery periods, while three maintained body temperature despite cold exposure. During the baseline period, infrared heat loss was relatively stable, followed by a rapid decrease of 5°C within 5 min of cold exposure. Heat loss continued to decrease linearly in the cold-exposure period by a further 10°C, but increased rapidly to baseline levels during the recovery period. A temperature change of between 20°C and 35°C was observed during the study, which was likely to be due to changes in vasoconstriction in the skin to conserve heat. The present study has highlighted the sensitivity of infrared thermal imaging to estimate heat loss from the skin in the newborn lamb and shown that rapid changes in heat loss occur in response to cold exposure.

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Liver Derived FGF21 Maintains Core Body Temperature During Acute Cold Exposure

Scientific Reports ◽

10.1038/s41598-018-37198-y ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 16

Author(s):

Magdalene Ameka ◽

Kathleen R. Markan ◽

Donald A. Morgan ◽

Lucas D. BonDurant ◽

Sharon O. Idiga ◽

...

Keyword(s):

Body Temperature ◽

Cold Exposure ◽

Core Body Temperature ◽

Acute Cold Exposure ◽

Core Body

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Effects of intermittent cold exposure varying in intensity on core body temperature and resting heat production of beef cattle

Canadian Journal of Animal Science ◽

10.4141/a00-118 ◽

2001 ◽

Vol 81 (4) ◽

pp. 459-465 ◽

Cited By ~ 6

Author(s):

R. D. Bergen ◽

A. D. Kennedy ◽

R. J. Christopherson

Keyword(s):

Body Temperature ◽

Beef Cattle ◽

Heat Production ◽

Cold Exposure ◽

Core Body Temperature ◽

Daily Maximum ◽

Adaptation Period ◽

Temperature Rhythms ◽

Core Body ◽

Vaginal Temperature

Crossbred beef heifers (n = 18) fed at 1.3× maintenance were exposed to summer daytime temperatures (20 ± 0.2°C) for 8 h (08:00 until 16:00) and to control (22°C), moderate (–6°C) or cold (–15°C) environments for 16 h daily (16:00 until 08:00) for a minimum 21-d adaptation period to investigate the effects of in tensity of intermittent cold exposure on vaginal temperature and resting heat production. Resting heat production was measured at the end of the adaptation period. Vaginal temperature was continuously monitored throughout the experiment using radiotelemetry. Vaginal temperature increased immediately after the onset of cold exposure in both moderate and cold treatments, peaked after 3 h, and returned to pre-exposure levels by the time the 16-h treatment ended. In contrast, vaginal temperatures of control heifers peaked only after feeding at 08:30. Treatment did not affect daily maximum (P= 0.60), mean (P = 0.72) or minimum (P = 0.34) vaginal temperatures, but heifers in both cold-exposed treatments spent more time (P = 0.03) with vaginal temperatures exceeding the daily mean vaginal temperature than control heifers. Compared to control heifers, the variability of vaginal temperature increased 1.8- and 2.2-fold in the moderate and cold treatments, respectively (P = 0.04), and did not change with time (P = 0.98 ). Resting heat production did not increase following 21 d of exposure to moderate and cold conditions. Results of this study indicate that intermittent cold exposure influenced circadian body temperature rhythms without increasing resting heat production. Key words: Beef cattle, thermoregulation, vaginal temperature, heat production.

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Influence of Cold-TRP Receptors on Cold-Influenced Behaviour

Pharmaceuticals ◽

10.3390/ph15010042 ◽

2021 ◽

Vol 15 (1) ◽

pp. 42

Author(s):

Dibesh Thapa ◽

Brentton Barrett ◽

Fulye Argunhan ◽

Susan D. Brain

Keyword(s):

Body Temperature ◽

Cold Exposure ◽

Transient Receptor Potential ◽

Trp Channels ◽

Core Body Temperature ◽

Physical Restraint ◽

Receptor Potential ◽

Whole Body ◽

Direct Role ◽

Core Body

The transient receptor potential (TRP) channels, TRPA1 and TRPM8, are thermo-receptors that detect cold and cool temperatures and play pivotal roles in mediating the cold-induced vascular response. In this study, we investigated the role of TRPA1 and TRPM8 in the thermoregulatory behavioural responses to environmental cold exposure by measuring core body temperature and locomotor activity using a telemetry device that was surgically implanted in mice. The core body temperature of mice that were cooled at 4 °C over 3 h was increased and this was accompanied by an increase in UCP-1 and TRPM8 level as detected by Western blot. We then established an effective route, by which the TRP antagonists could be administered orally with palatable food. This avoids the physical restraint of mice, which is crucial as that could influence the behavioural results. Using selective pharmacological antagonists A967079 and AMTB for TRPA1 and TRPM8 receptors, respectively, we show that TRPM8, but not TRPA1, plays a direct role in thermoregulation response to whole body cold exposure in the mouse. Additionally, we provide evidence of increased TRPM8 levels after cold exposure which could be a protective response to increase core body temperature to counter cold.

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