The effects of exercise and cold exposure on mitochondrial biogenesis in skeletal muscle and white adipose tissue

( Nana Chung ),( Jonghoon Park ),( Kiwon Lim ) 한국운동영양학회 2017 Physical Activity and Nutrition (Phys Act Nutr) Vol.21 No.2

[Purpose] The purpose of this study was to deter-mine whether exercise or/and cold exposure regulate mitochondria biogenesis-related gene expression in soleus and inguinal adipose tissue of mice. [Methods] Forty ICR 5-week old male mice were divided into four groups: thermoneutrality-untrained (23 ± 1 ℃ in room temperature, n=10), cold-water immer-sion (24 ± 1 ℃, n=10), exercise in neutral temperature (34 ± 1 ℃, n=10), and exercise in cold temperature (24 ± 1 ℃, n=10). The mice performed swimming exer-cise (30 min to 60 min, 5 times) for 8 weeks. After 8 weeks, we confirmed mitochondrial biogenesis-relat-ed gene expression changes for peroxisome prolif-erator- activated receptor gamma coactivator-1 alpha (PGC-1α), nuclear respiratory factors 1 (NRF1), and mitochondrial transcription factor A (Tfam) in soleus muscle and inguinal adipose tissue, and the related protein expression in soleus muscle. [Results] In soleus muscle, PGC-1α expression significantly increased in response to cold exposure (p=0.006) and exercise (p=0.05). There was also significant interaction between exercise and cold ex-posure (p = 0.005). Only exercise had a significant ef-fect on NRF1 relative expression (p=0.001). Neither cold exposure nor the interaction showed significant effects (p=0.1222 and p=0.875, respectively). Rel-ative Tfam expression did not show any significant effect from exercise. In inguinal adipose tissue, rela-tive PGC-1α expression did not significantly change in any group. NRF1 expression showed a significant change from exercise (p=0.01) and cold exposure (p=0.011). There was also a significant interaction between exercise and cold exposure (p=0.000). Tfam mRNA expression showed a significant effect from exercise (p=0.000) and an interaction between exercise and cold exposure (p=0.001). Only temperature significantly affected PGC-1α protein levels (p=0.045). Neither exercise nor the interaction were significant (p=0.397 and p=0.292, respectively). NRF1 protein levels did not show a significant effect in any experimental treatments. Tfam protein levels showed a significant effect in the exercise group (p=0.012), but effects of neither cold exposure nor the interaction were significant (p=0.085 and p=0.374, respectively). [Conclusion] Exercise and cold exposure pro-moted increased expression of mitochondrial bio-genesis- related genes in soleus muscle. Only cold exposure had a significant effect on PGC-1α protein expression and only exercise had a significant effect on Tfam protein expression. In inguinal adipose tissue, there was interaction between exercise and cold exposure in expression of mitochondrial bio-genesis- related genes.

BODY HEAT CONTENT, HEAT PRODUCTION AND RESPIRATION IN SHEEP EXPOSED TO INTERMITTENT COLD

Lee, S.R.,Sasaki, Y. Asian Australasian Association of Animal Productio 1994 Animal Bioscience Vol.7 No.3

Five adult sheep were exposed to intermittent cold for 12 h (18:00-06:00) at an air temperature of $5{\pm}1^{\circ}C$ followed by 12 h (06:00-18:00) at $25{\pm}2^{\circ}C$ over a period of 8 days continuously. Carotid artery blood (Tc), mean skin (Ts) and mean body (Tb = 0.86 Tc + 0.14 Ts) temperatures, heat production rate (HP), respiratory evaporative heat loss, respiration rate (RR) and volume were measured before and after exposure. Tc during the 12 h cold period of intermittent cold exposure was similar to that during the corresponding period in the warm environment, while Tc in the $25^{\circ}C$ of intermittent cold was higher (p < 0.05) than that in the corresponding period in the warm environment. Ts during the cold period markedly decreased (p < 0.001) by about $9^{\circ}C$ when compared with that in the corresponding time period in the warm environment, while Ts during the $25^{\circ}C$ period of intermittent cold recovered to a similar level to that in the warm environment. Tb was lower (p < 0.001) during the cold period of intermittent cold, whereas a slight increase in Tb during the $25^{\circ}C$ period of intermittent cold was significant (p < 0.05) when compared with the value during the similar period in the warm environment. HP was greatly increased (p < 0.001) by cold exposure, followed by an immediate decrease during the first one hour of the 12 h warm period, reaching a similar level to that in the warm environment. A lower (p < 0.05) RR was observed during both the cold and $25^{\circ}C$ period of intermittent cold than during the corresponding periods in the warm environment. The results of the present investigation clearly show that the body temperature of sheep increased during a 12 h warm period following 12 h of exposure to cold. These results suggest that during a warm period of an intermittent cold exposure cycle, heat could be shored in the animal body.

한랭노출과 고혈압의 연관성

장태원,김윤규,윤동영,이창희,홍영습,신해림,정갑열,김준연 大韓産業醫學會 2001 대한직업환경의학회지 Vol.13 No.4

Objectives : This study was carried out to suggest preventive methods for hypertension in cold-exposed workers. Methods : In 11 refs·iteration industries, 68 workers working in refrigerated areas more than one time per day were selected as the exposed group, and 68 workers not exposed to cold were selected as the control group. We interviewed the subjects with a questionnaire covering occupational history, and conducted clinical and laboratory tests including measurements of blood pressure and core temperature. Results : The systolic blood pressure in the exposed group(130.0±13.3 mmHg) was significantly higher than that recorded In the control group(118.3±12.1 mmHg), as was the diastolic blood pressure in the exposed group(82.7±8.5 mmHg) versus the control group(77.4±8.7 mmHg). The core temperature in the exposed group(36.1±0.7℃) was significantly lower than that experienced in the control group (36.4±0.5℃). In logistic regression analysis, age, cold exposure severity and milk intake were significant variables, with odds ratios of 5.204(95 % CI 1.440∼18.812), 2.674(95 % CI 1.080∼6.618), and 0.364(95 % Cl 0.141∼0.942) , respectively. Conclusions : Our study suggests that cold-exposed workers have higher a higher risk of hypertension, and that their core temperature is lower. Risk factors affecting hyper-tension of cold-exposed workers include age, cold exposure severity and milk intake. For the prevention of hypertension, cold-exposed workers should minimize cold-exposure time as much as possible.

Irisin 매개 운동 및 저온 노출이 백색지방 갈변화에 미치는 영향 및 메커니즘: a review

전장,왕영,이진우,김재철 한국체육과학회 2023 한국체육과학회지 Vol.32 No.3

The present review aims to identify the similarities and differences in the effects and mechanisms of irisin-mediated cold exposure and exercise on WAT browning, by considering irisin as both a myokine and adipokine. And with an attempt to elucidate the reasons for conflicting results in previous studies. A comprehensive search of the PubMed database was performed using the keywords “cold exposure”, “exercise/training”, “FNDC5/irisin”, and “browning/beigeing”. The results are as follows: 1. The effects of exercise on irisin concentrations and WAT browning were mainly due to the intervention of the duration, while cold exposure was mainly due to stimulus intensity; 2. while there is considerable literature available on exercise that explores its type, intensity, frequency, and duration, research on cold exposure has primarily focused on temperature and duration, with limited attention given to the type and frequency; 3. the molecular mechanisms underlying irisin-mediated effects in humans remain largely unexplored. Despite the conflicting results reported in previous studies, the WAT browning induced by exercise combined with cold exposure continues to be an attractive strategy for the prevention and treatment of obesity.

The Effect of Cold Temperature and Exercise on BAT and Browning of WAT

정나나,임기원 한국체육학회 2018 International journal of human movement science Vol.12 No.2

The present study aimed to investigate the effects of cold exposure and/or exercise on resting energy metabolism over 24 h and on BAT activity and browning of WAT related gene responses. Forty ICR male mice were divided into four groups: thermoneutrality-untrained (23 ± 1°C in room temperature, n=10), cold-water immersion (24 ± 1°C, n=10), exercise in neutral temperature (34 ± 1°C, n=10), and exercise in cold temperature (24 ± 1°C, n=10). The mice performed swim training (30 min to 60 min, 5 days/week) for 8 weeks. After end of experiment, we confirmed BAT activity and browning of WAT-related gene expression changes in interscapular-BAT and inguinal adipose tissue, and measured resting energy metabolism over 24 h. The results showed that the relative tissue weights of BAT and inguinal fat tissue differed by temperature (p = 0.016, p= 0.001 respectively). The UCP1 mRNA expression in BAT showed a significant effect in the exercised groups (p = 0.038). The sum of the oxygen uptake, only a significant temperature effect (p = 0.040) was observed and the average of the RER showed a significant temperature (p = 0.024) and exercise (p = 0.008) effect. Our data demonstrate that cold exposure and exercise independently induces the gene expression of thermogenic markers and the energy metabolic rate. The relative expression of these markers and the change of the energy metabolism indicators differed across the tissues and experimental treatments. In conclusion, our results suggest that cold exposure and exercise has no synergy effect on thermogenic markers of BAT and beige/brite adipose tissue and energy metabolism over 24h.

The Effect of Cold Temperature and Exercise on BAT and Browning of WAT

( Nana Chung ),( Kiwon Lim ) 한국체육학회 2018 International journal of human movement science Vol.12 No.2

The present study aimed to investigate the effects of cold exposure and/or exercise on resting energy metabolism over 24 h and on BAT activity and browning of WAT related gene responses. Forty ICR male mice were divided into four groups: thermoneutrality-untrained (23 ± 1°C in room temperature, n=10), cold-water immersion (24 ± 1°C, n=10), exercise in neutral temperature (34 ± 1°C, n=10), and exercise in cold temperature (24 ± 1°C, n=10). The mice performed swim training (30 min to 60 min, 5 days/week) for 8 weeks. After end of experiment, we confirmed BAT activity and browning of WAT-related gene expression changes in interscapular-BAT and inguinal adipose tissue, and measured resting energy metabolism over 24 h. The results showed that the relative tissue weights of BAT and inguinal fat tissue differed by temperature (p = 0.016, p= 0.001 respectively). The UCP1 mRNA expression in BAT showed a significant effect in the exercised groups (p = 0.038). The sum of the oxygen uptake, only a significant temperature effect (p = 0.040) was observed and the average of the RER showed a significant temperature (p = 0.024) and exercise (p = 0.008) effect. Our data demonstrate that cold exposure and exercise independently induces the gene expression of thermogenic markers and the energy metabolic rate. The relative expression of these markers and the change of the energy metabolism indicators differed across the tissues and experimental treatments. In conclusion, our results suggest that cold exposure and exercise has no synergy effect on thermogenic markers of BAT and beige/brite adipose tissue and energy metabolism over 24h.

자연요인과 Irisin 발현 고찰

정승록,어수주 동방문화대학원대학교 자연치유연구소 2018 자연치유연구 Vol.3 No.1

This study was carried out to investigate the expression of Irisin(browning) by natural factors such as 'cold' and 'aging' and was undertaken to understand the health factors and positive effects associated with fat metabolism, which can be attributed to natural factors. First study was that 6 healthy subjects participated in and exposed cold for 4 weeks(300 min/day, 5 times/ week, -15°C~-25°C). Body composition, isokinetic muscular function(60°/s and 240°/s by Humac Norm) and irisin concentration were measured pre and post cold exposure. Second study was that we examined the changes of serum Irisin expression by aging process(10wk, 80wk) and aerobic exercise. Conduct of aerobic exercise with regular cold exposure or aging process is a factor that increases browning of white fat The increase of Irisin is a positive factor for the imbalance of fat metabolism and improvement of performance

Brown Adipose Tissue as a Therapeutic Target for Obesity: From Mice to Humans

Masayuki Saito 대한비만학회 2015 The Korean journal of obesity Vol.24 No.1

Brown adipose tissue (BAT) is a site of sympathetically activated non-shivering thermognenesis during cold exposure and after spontaneoushyperphagia, thereby involving in the autonomic regulation of energy balance and body fatness. Recent radionuclide studies have demonstratedthe existence of metabolically active BAT in adult humans. Human BAT is activated by acute cold exposure, particularly in winter, and contributesto cold-induced increase in whole-body energy expenditure. The metabolic activity of BAT is lower in older and obese individuals. Theinverse relationship between the BAT activity and body fatness suggests that BAT, because of its energy dissipating activity, is protective againstbody fat accumulation. In fact, either repeated cold exposure or daily ingestion of some food ingredients acting on transient receptor potentialchannels recruited BAT in association with increased energy expenditure and decreased body fatness. Thus, BAT is a promising target for combatingobesity and related metabolic disorders in humans.

다이버의 일회성 저수온 노출이 혈중 FGF21, Irisin 및 T3에 미치는 영향

전유나 ( Yu Nah Jeon ),라승구 ( Seung Goo Ra ),김창근 ( Chang Keun Kim ) 한국운동생리학회 2015 운동과학 Vol.24 No.3

PURPOSE: It has been understood that brown fat or beige adipose tissues can facilitate heat production through non-shivering thermogenesis. FGF21, irisin, or T3 hormones are believed to enhance brown fat activation and increase in cold environment and exercise. The purpose of this study was to determine the changes of circulating FGF21, irisin, T3 hormone concentrations during the acute diving activity in divers who have been undergone long-term intermittent cold exposure. METHODS: Seven SCUBA divers who have been diving at least for 5 years with 50 to 100 diving records per year participated in this study. A bout of acute diving was performed in the east sea (13-14 ℃) for 30 min. Blood samples were obtained from arm vein at pre- and post-diving, and after an hour recovery. Serum FGF21, Plasma irisin and serum T3, TG and FFA were assayed. RESULTS: Serum FGF21 level was increased after 30 min of diving (p=.043, 138%) compared to pre-diving and after one hour of recovery to pre-diving level (p=.018, 65%). However, plasma irisin, T3 , FFA, TG levels were unchanged both after post-diving and one hour recovery (p>.05). CONCLUSIONS: It is concluded that heat generation through non-shivering thermogenesis may play a major role during the acute diving activity in divers who have been undergone long-term intermittent cold exposure.

Brown Adipose Tissue as a Regulator of Energy Expenditure and Body Fat in Humans

Masayuki Saito 대한당뇨병학회 2013 Diabetes and Metabolism Journal Vol.37 No.1

Brown adipose tissue (BAT) is recognized as the major site of sympathetically activated nonshivering thermogenesis during cold exposure and after spontaneous hyperphagia, thereby controling whole-body energy expenditure and body fat. In adult humans,BAT has long been believed to be absent or negligible, but recent studies using fluorodeoxyglucose-positron emission tomography,in combination with computed tomography, demonstrated the existence of metabolically active BAT in healthy adult humans. Human BAT is activated by acute cold exposure, being positively correlated to cold-induced increases in energy expenditure. The metabolic activity of BAT differs among individuals, being lower in older and obese individuals. Thus, BAT is recognized as a regulator of whole-body energy expenditure and body fat in humans as in small rodents, and a hopeful target combating obesity and related disorders. In fact, there are some food ingredients such as capsaicin and capsinoids, which have potential to activate and recruit BAT via activity on the specific receptor, transient receptor potential channels, thereby increasing energy expenditure and decreasing body fat modestly and consistently.