Effect of interleukin-18 on mouse core body temperature

We have studied, using a telemetry system, the pyrogenic properties of recombinant murine interleukin-18 (rmIL-18) injected into the peritoneum of C57BL/6 mice. The effect of IL-18 was compared with the febrile response induced by human IL-1β, lipopolysaccharide (LPS), and recombinant murine interferon-γ (rmIFN-γ). Both IL-1β and LPS induced a febrile response within the first hour after the intraperitoneal injection, whereas rmIL-18 (10–200 μg/kg) and rmIFN-γ (10–150 μg/kg) did not cause significant changes in the core body temperature of mice. Surprisingly, increasing doses of IL-18, injected intraperitoneally 30 min before IL-1β, significantly reduced the IL-1β-induced fever response. In contrast, the same pretreatment with IL-18 did not modify the febrile response induced by LPS. IFN-γ does not seem to play a role in the IL-18-mediated attenuation of IL-1β-induced fever. In fact, there was no elevation of IFN-γ in the serum of mice treated with IL-18, and a pretreatment with IFN-γ did not modify the fever response induced by IL-1β. We conclude that IL-18 is not pyrogenic when injected intraperitoneally in C57BL/6 mice. Furthermore, a pretreatment with IL-18, 30 min before IL-1β, attenuates the febrile response induced by IL-1β.

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Pathophysiology of Fever and Application of Infrared Thermography (IRT) in the Detection of Sick Domestic Animals: Recent Advances

Animals ◽

10.3390/ani11082316 ◽

2021 ◽

Vol 11 (8) ◽

pp. 2316

Author(s):

Daniel Mota-Rojas ◽

Dehua Wang ◽

Cristiane Gonçalves Titto ◽

Jocelyn Gómez-Prado ◽

Verónica Carvajal-de la Fuente ◽

...

Keyword(s):

Body Temperature ◽

Infrared Thermography ◽

Core Body Temperature ◽

The Body ◽

Farm Animals ◽

Economic Losses ◽

Febrile Response ◽

Temperature Range ◽

Stable Temperature ◽

Core Body

Body-temperature elevations are multifactorial in origin and classified as hyperthermia as a rise in temperature due to alterations in the thermoregulation mechanism; the body loses the ability to control or regulate body temperature. In contrast, fever is a controlled state, since the body adjusts its stable temperature range to increase body temperature without losing the thermoregulation capacity. Fever refers to an acute phase response that confers a survival benefit on the body, raising core body temperature during infection or systemic inflammation processes to reduce the survival and proliferation of infectious pathogens by altering temperature, restriction of essential nutrients, and the activation of an immune reaction. However, once the infection resolves, the febrile response must be tightly regulated to avoid excessive tissue damage. During fever, neurological, endocrine, immunological, and metabolic changes occur that cause an increase in the stable temperature range, which allows the core body temperature to be considerably increased to stop the invasion of the offending agent and restrict the damage to the organism. There are different metabolic mechanisms of thermoregulation in the febrile response at the central and peripheral levels and cellular events. In response to cold or heat, the brain triggers thermoregulatory responses to coping with changes in body temperature, including autonomic effectors, such as thermogenesis, vasodilation, sweating, and behavioral mechanisms, that trigger flexible, goal-oriented actions, such as seeking heat or cold, nest building, and postural extension. Infrared thermography (IRT) has proven to be a reliable method for the early detection of pathologies affecting animal health and welfare that represent economic losses for farmers. However, the standardization of protocols for IRT use is still needed. Together with the complete understanding of the physiological and behavioral responses involved in the febrile process, it is possible to have timely solutions to serious problem situations. For this reason, the present review aims to analyze the new findings in pathophysiological mechanisms of the febrile process, the heat-loss mechanisms in an animal with fever, thermoregulation, the adverse effects of fever, and recent scientific findings related to different pathologies in farm animals through the use of IRT.

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Temperature Monitoring and Perioperative Thermoregulation

Anesthesiology ◽

10.1097/aln.0b013e31817f6d76 ◽

2008 ◽

Vol 109 (2) ◽

pp. 318-338 ◽

Cited By ~ 341

Author(s):

Daniel I. Sessler ◽

David S. Warner ◽

Mark A. Warner

Keyword(s):

Body Temperature ◽

General Anesthesia ◽

Core Temperature ◽

Core Body Temperature ◽

Neuraxial Anesthesia ◽

General Anesthetics ◽

The Core ◽

Core Body ◽

Dose Dependent ◽

Body Heat

Most clinically available thermometers accurately report the temperature of whatever tissue is being measured. The difficulty is that no reliably core-temperature-measuring sites are completely noninvasive and easy to use-especially in patients not undergoing general anesthesia. Nonetheless, temperature can be reliably measured in most patients. Body temperature should be measured in patients undergoing general anesthesia exceeding 30 min in duration and in patients undergoing major operations during neuraxial anesthesia. Core body temperature is normally tightly regulated. All general anesthetics produce a profound dose-dependent reduction in the core temperature, triggering cold defenses, including arteriovenous shunt vasoconstriction and shivering. Anesthetic-induced impairment of normal thermoregulatory control, with the resulting core-to-peripheral redistribution of body heat, is the primary cause of hypothermia in most patients. Neuraxial anesthesia also impairs thermoregulatory control, although to a lesser extent than does general anesthesia. Prolonged epidural analgesia is associated with hyperthermia whose cause remains unknown.

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Monitoring of the core body temperature of cows using implantable wireless thermometers

Computers and Electronics in Agriculture ◽

10.1016/j.compag.2019.06.004 ◽

2019 ◽

Vol 163 ◽

pp. 104849 ◽

Cited By ~ 1

Author(s):

Wataru Iwasaki ◽

Shuichi Ishida ◽

Daisuke Kondo ◽

Yuichi Ito ◽

Jun Tateno ◽

...

Keyword(s):

Body Temperature ◽

Core Body Temperature ◽

The Core ◽

Core Body

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Skipping Breakfast for 6 Days Delayed the Circadian Rhythm of the Body Temperature without Altering Clock Gene Expression in Human Leukocytes

Nutrients ◽

10.3390/nu12092797 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2797 ◽

Cited By ~ 1

Author(s):

Hitomi Ogata ◽

Masaki Horie ◽

Momoko Kayaba ◽

Yoshiaki Tanaka ◽

Akira Ando ◽

...

Keyword(s):

Gene Expression ◽

Body Temperature ◽

Clock Gene ◽

Core Body Temperature ◽

The Core ◽

Clock Gene Expression ◽

Meal Timing ◽

Dim Light ◽

Core Body ◽

Skipping Breakfast

Breakfast is often described as “the most important meal of the day” and human studies have revealed that post-prandial responses are dependent on meal timing, but little is known of the effects of meal timing per se on human circadian rhythms. We evaluated the effects of skipping breakfast for 6 days on core body temperature, dim light melatonin onset, heart rate variability, and clock gene expression in 10 healthy young men, with a repeated-measures design. Subjects were provided an isocaloric diet three times daily (3M) or two times daily (2M, i.e., breakfast skipping condition) over 6 days. Compared with the 3M condition, the diurnal rhythm of the core body temperature in the 2M condition was delayed by 42.0 ± 16.2 min (p = 0.038). On the other hand, dim light melatonin onset, heart rate variability, and clock gene expression were not affected in the 2M condition. Skipping breakfast for 6 days caused a phase delay in the core body temperature in healthy young men, even though the sleep–wake cycle remained unchanged. Chronic effects of skipping breakfast on circadian rhythms remain to be studied.

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Telemetry System for Measuring Core Body Temperature in Livestock and Poultry

10.13031/2013.23649 ◽

2001 ◽

Cited By ~ 3

Author(s):

T M Brown-Brandl ◽

T Yanagi ◽

H Xin ◽

R.S Gates ◽

R Bucklin ◽

...

Keyword(s):

Body Temperature ◽

Core Body Temperature ◽

Telemetry System ◽

Core Body

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The Use of Percutaneous Thermal Sensing Microchips for Body Temperature Measurements in Horses Prior to, during and after Treadmill Exercise

Animals ◽

10.3390/ani10122274 ◽

2020 ◽

Vol 10 (12) ◽

pp. 2274

Author(s):

Hyungsuk Kang ◽

Rebeka R. Zsoldos ◽

Solomon M. Woldeyohannes ◽

John B. Gaughan ◽

Albert Sole Guitart

Keyword(s):

Body Temperature ◽

Core Body Temperature ◽

Central Venous ◽

Exertional Heat Illness ◽

The Core ◽

Thermal Sensing ◽

Positive Correlations ◽

The Right ◽

Nuchal Ligament ◽

Core Body

Accurately measuring body temperature in horses will improve the management of horses suffering from or being at risk of developing postrace exertional heat illness. PTSM has the potential for measuring body temperature accurately, safely, rapidly, and noninvasively. This study was undertaken to investigate the relation between the core body temperature and PTSM temperatures prior to, during, and immediately after exercise. The microchips were implanted into the nuchal ligament, the right splenius, gluteal, and pectoral muscles, and these locations were then compared with the central venous temperature, which is considered to be the “gold standard” for assessing core body temperature. The changes in temperature of each implant in the horses were evaluated in each phase (prior to, during, and immediately postexercise) and combining all phases. There were strong positive correlations ranging from 0.82 to 0.94 (p < 0.001) of all the muscle sites with the central venous temperature when combining all the phases. Additionally, during the whole period, PTSM had narrow limits of agreement (LOA) with central venous temperature, which inferred that PTSM is essentially equivalent in measuring horse body temperature. Overall, the pectoral PTSM provided a valid estimation of the core body temperature.

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A study of the calibration for the core body temperature calculation using ear canal temperature measured by thermistor

The Proceedings of the Symposium on sports and human dynamics ◽

10.1299/jsmeshd.2019.a-32 ◽

2019 ◽

Vol 2019 (0) ◽

pp. A-32

Author(s):

Koki IKEJIRI ◽

Hiromu KIHARA ◽

Shota ISHIZAKI ◽

Jihyoung LEE

Keyword(s):

Body Temperature ◽

Core Body Temperature ◽

Ear Canal ◽

The Core ◽

Temperature Calculation ◽

Core Body

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Heterothermy is associated with reduced fitness in wild rabbits

Biology Letters ◽

10.1098/rsbl.2017.0521 ◽

2017 ◽

Vol 13 (12) ◽

pp. 20170521 ◽

Cited By ~ 7

Author(s):

Shane K. Maloney ◽

Maija K. Marsh ◽

Steven R. McLeod ◽

Andrea Fuller

Keyword(s):

Body Temperature ◽

Oryctolagus Cuniculus ◽

Reproductive Output ◽

Core Body Temperature ◽

The Body ◽

The Core ◽

Temperature Rhythm ◽

Body Temperature Rhythm ◽

Core Body ◽

Growth And Reproduction

An increase in variation in the 24 h pattern of body temperature (heterothermy) in mammals can be induced by energy and water deficits. Since performance traits such as growth and reproduction also are impacted by energy and water balance, we investigated whether the characteristics of the body temperature rhythm provide an indication of the reproductive success of an individual. We show that the amplitude of the daily rhythm of body temperature in wild rabbits ( Oryctolagus cuniculus ) prior to breeding is inversely related to the number of pregnancies in the subsequent seven months, while the minimum daily body temperature is positively correlated to the number of pregnancies. Because reproductive output could be predicted from characteristics of the core body temperature rhythm prior to the breeding season, we propose that the pattern of the 24 h body temperature rhythm could provide an index of animal fitness in a given environment.

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Exercise activates compensatory thermoregulatory reaction in rats: a modeling study

Journal of Applied Physiology ◽

10.1152/japplphysiol.00392.2015 ◽

2015 ◽

Vol 119 (12) ◽

pp. 1400-1410 ◽

Cited By ~ 8

Author(s):

Yeonjoo Yoo ◽

Michelle LaPradd ◽

Hannah Kline ◽

Maria V. Zaretskaia ◽

Abolhassan Behrouzvaziri ◽

...

Keyword(s):

Body Temperature ◽

Heat Generation ◽

Heat Production ◽

Core Body Temperature ◽

Heat Stroke ◽

The Body ◽

Model Parameters ◽

The Core ◽

Treadmill Speed ◽

Core Body

The importance of exercise is increasingly emphasized for maintaining health. However, exercise itself can pose threats to health such as the development of exertional heat shock in warm environments. Therefore, it is important to understand how the thermoregulation system adjusts during exercise and how alterations of this can contribute to heat stroke. To explore this we measured the core body temperature of rats ( Tc) running for 15 min on a treadmill at various speeds in two ambient temperatures ( Ta = 25°C and 32°C). We assimilated the experimental data into a mathematical model that describes temperature changes in two compartments of the body, representing the muscles and the core. In our model the core body generates heat to maintain normal body temperature, and dissipates it into the environment. The muscles produce additional heat during exercise. According to the estimation of model parameters, at Ta = 25°C, the heat generation in the core was progressively reduced with the increase of the treadmill speed to compensate for a progressive increase in heat production by the muscles. This compensation was ineffective at Ta = 32°C, which resulted in an increased rate of heat accumulation with increasing speed, as opposed to the Ta = 25°C case. Interestingly, placing an animal on a treadmill increased heat production in the muscles even when the treadmill speed was zero. Quantitatively, this “ready-to-run” phenomenon accounted for over half of the heat generation in the muscles observed at maximal treadmill speed. We speculate that this anticipatory response utilizes stress-related circuitry.

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