Article

Adaptation related to cytokines in man: Effects of regular swimming in ice-cold water

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  • South Carelia Central Hospital, Finland
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Abstract

The cytokine response after thermal stress (sauna + swimming in ice-cold water) was investigated in subjectively healthy persons. Two groups were studied at the end of the winter season: habitual and inexperienced winter swimmers. Blood was collected at rest, after a sauna bath and after a short swim in ice-cold water. Conventional methods and ELISA kits were used to determined the blood picture, serum cortisol and dehydroepiandrosterone sulphate, plasma anti-diuretic hormone (ADH) levels, and the levels of several cytokines in plasma and in the supernatants of blood cell cultures which were stimulated with lipopolysaccharide (LPS). In regular winter swimmers, the concentrations of plasma interleukin 6 (IL-6), leukocytes, and monocytes at rest were significantly higher than in inexperienced subjects. In experienced female winter swimmers, the plasma concentration of the soluble receptor for IL-6 was significantly lower than in inexperienced female swimmers. In both groups, granulocytosis, haemoconcentration and significant increases in the concentrations of ADH, cortisol and IL-6 were observed after the stimuli. However, the changes in the cortisol concentration were dramatically larger in habitual winter swimmers. A significant correlation was found between the delta values of cortisol and the basal concentrations of IL-6. In cell cultures, the LPS-induced release of IL-1beta and IL-6 was higher at rest in the inexperienced winter swimmers. This release was dramatically suppressed after exposure to the stimuli in the inexperienced winter swimmers but tended to increase in the regular winter swimmers. These stresses appear to challenge both the neuro-endocrine and the immune systems and the results indicate that adaptive mechanisms occur in habitual winter swimmers.

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... This finding is consistent with previous research by Janský et al. who also showed no changes in the total leukocyte count after a 6-week repeated CWI intervention (Janský et al., 1996a). In the same study, Janský et al. reported a slight increase in monocyte numbers (Janský et al., 1996a) and Dugué et al. found that winter-swimmers exposed to thermal stress had higher numbers of monocytes compared to non-habituated individuals (Dugué and Leppänen, 2000). Contrary to these observations, a 3-week repeated CWI intervention in this present study had no significant effect on monocyte numbers but only resulted in a minimal decrease in neutrophil numbers (median difference: −0.65 × 10 3 /µL) and proportion (median difference: −2.77%). ...
... Habitual winter-swimmers have been shown to have increased numbers of monocytes compared to inexperienced individuals. Since the winter-swimmers often practise ice-cold water swimming in combination with systemic heat (i.e., hot sauna), the observed differences in leukocyte levels suggest adaptive mechanisms in response to thermal stress in general (Dugué and Leppänen, 2000). Therefore, the effects of cold exposure through repeated CWI remain to be fully elucidated. ...
... Therefore, the aim of this study was to explore the effects of a 3-week repeated CWI intervention on total leukocyte numbers and proportions (neutrophils, basophils, eosinophils, monocytes, lymphocytes) and cardiovascular factors (MAP, HR) in healthy men. Based on previous studies (Janský et al., 1996a;Dugué and Leppänen, 2000), it was hypothesized that a 3-week repeated CWI intervention may increase the number of monocytes. Furthermore, it was hypothesized that a 3week repeated CWI intervention could potentially reduce resting MAP and HR. ...
... Habitual winter-swimmers have been shown to have increased numbers of monocytes compared to inexperienced individuals. Since the winter-swimmers often practise ice-cold water swimming in combination with systemic heat (i.e., hot sauna), the observed differences in leukocyte levels suggest adaptive mechanisms in response to thermal stress in general (Dugué and Leppänen, 2000). Therefore, the effects of cold exposure through repeated CWI remain to be fully elucidated. ...
... Therefore, the aim of this study was to explore the effects of a 3-week repeated CWI intervention on total leukocyte numbers and proportions (neutrophils, basophils, eosinophils, monocytes, lymphocytes) and cardiovascular factors (MAP, HR) in healthy men. Based on previous studies (Janský et al., 1996a;Dugué and Leppänen, 2000), it was hypothesized that a 3-week repeated CWI intervention may increase the number of monocytes. Furthermore, it was hypothesized that a 3-week repeated CWI intervention could potentially reduce resting MAP and HR. ...
... This finding is consistent with previous research by Janský et al. who also showed no changes in the total leukocyte count after a 6-week repeated CWI intervention (Janský et al., 1996a). In the same study, Janský et al. reported a slight increase in monocyte numbers (Janský et al., 1996a) and Dugué et al. found that winterswimmers exposed to thermal stress had higher numbers of monocytes compared to non-habituated individuals (Dugué and Leppänen, 2000). Contrary to these observations, a 3week repeated CWI intervention in this present study had no significant effect on monocyte numbers but only resulted in a minimal decrease in neutrophil numbers (median difference: −0.65 × 10 3 /µL) and proportion (median difference: −2.77%). ...
Article
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Aim: This exploratory study aimed to investigate the effects of a 3-week repeated cold water immersion (CWI) intervention on leukocyte counts and cardiovascular factors (mean arterial pressure [MAP], heart rate [HR]) in healthy men. Methods: A total of n = 12, non-cold-adapted men (age: 25.2 ± 4.0 years; height: 177.8 ± 5.6 cm; weight: 73.8 ± 6.5 kg) were randomly allocated to the CWI or control (CON) group. The CWI group underwent a 3-week repeated CWI intervention (12min at 7°C, 4x/week). The CON group did not receive any cold exposure or therapy. Total leukocyte numbers and proportions (neutrophils, basophils, eosinophils, monocytes, lymphocytes) and cardiovascular factors (MAP, HR) were assessed at baseline and after the 3-week intervention period. Results: Total leukocyte count decreased in CWI (p = 0.027, 95% CI −2.35 to −0.20 × 10³/µL) and CON (p = 0.043, 95% CI −2.75 to −0.50 × 10³/µL). CWI showed a decrease in neutrophil number (p = 0.028, 95% CI −1.55 to −0.25 × 10³/µL) and proportion (p = 0.046, 95% CI −6.42 to 0.56%). In contrast, CON showed no significant change (p > 0.05). No differences were found for other leukocyte subtypes in CWI or CON (all p > 0.05). MAP (p = 0.028, 95% CI −17 to −8 mmHg) and HR (p = 0.027, 95% CI −7 to −2 bpm) were reduced in CWI, whereas CON showed no change (p > 0.05). Conclusion: The results suggest no relevant effects of 3-week repeated CWI on leukocyte counts in healthy men. Due to methodological limitations, the effects on the investigated cardiovascular factors remain unclear. Further studies with larger sample sizes are needed to examine the effects on immune function and cardiovascular health.
... In another study, which compared habitual and inexperienced winter swimmers, the authors reported significantly higher concentrations of plasma IL-6, leukocytes and monocytes in winter swimmers compared to inexperienced subjects. This indicates that adaptive mechanisms occur in habitual winter swimmers [82]. In a study investigating the effects of a short-term immersion in cold water following a bout of exercise, IL-6 levels were found to be significantly higher compared to postexercise rest at room temperature [83]. ...
... While many of the studies demonstrated significant effects of CWI on various physiological and biochemical parameters, the question as to whether these are beneficial or not for health is difficult to assess. One of the problems is that some of the studies involve passive CWI [46,47,52,54,56,58,61,[63][64][65]71,72,76,77,81,85,[96][97][98], while others deal with active CWI [42,45,50,55,57,62,[66][67][68][73][74][75]79,82,[86][87][88][89][90][93][94][95]. Many of the research studies were based on cold adapted winter swimmers [41,67,68,71,75,77,82,85,86,[88][89][90]94,95]. ...
... One of the problems is that some of the studies involve passive CWI [46,47,52,54,56,58,61,[63][64][65]71,72,76,77,81,85,[96][97][98], while others deal with active CWI [42,45,50,55,57,62,[66][67][68][73][74][75]79,82,[86][87][88][89][90][93][94][95]. Many of the research studies were based on cold adapted winter swimmers [41,67,68,71,75,77,82,85,86,[88][89][90]94,95]. Other investigations on the beneficial effects of regular CWI were performed on subjects with no previous experience [46,47,52,54,[56][57][58][63][64][65]69,70,[72][73][74]76,81,87,92,93]. ...
Article
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This review is based on a multiple database survey on published literature to determine the effects on health following voluntary exposure to cold-water immersion (CWI) in humans. After a filtering process 104 studies were regarded relevant. Many studies demonstrated significant effects of CWI on various physiological and biochemical parameters. Although some studies were based on established winter swimmers, many were performed on subjects with no previous winter swimming experience or in subjects not involving cold-water swimming, for example, CWI as a post-exercise treatment. Clear conclusions from most studies were hampered by the fact that they were carried out in small groups, often of one gender and with differences in exposure temperature and salt composition of the water. CWI seems to reduce and/or transform body adipose tissue, as well as reduce insulin resistance and improve insulin sensitivity. This may have a protective effect against cardiovascular, obesity and other metabolic diseases and could have prophylactic health effects. Whether winter swimmers as a group are naturally healthier is unclear. Some of the studies indicate that voluntary exposure to cold water has some beneficial health effects. However, without further conclusive studies, the topic will continue to be a subject of debate.
... The study of the effects of cold water swimming on the function of the immune system (especially leukocytes and immunoglobulins) has led to contrasting results. This is possibly due to the majority of studies examining individuals and study protocols of unfamiliar people who take a short bath in ice-cold water [69] longer static cold water swimming (stay in the cold water without moving) [27] and experienced long-distance swimmers who trained for 8 h (dynamic cold water swimming) [62] were very different. ...
... However, it is difficult to measure in vivo immune function adequately, therefore upper respiratory tract infection is often a useful measure as it is a very common infection that affects both congenital and acquired elements [71]. Dugué and Leppänen [69] found that trained cold water swimmers had a higher concentration of certain leukocytes than those who were not cold acclimatized. The authors also examined the reactions of both groups to a brief immersion in ice-cold water. ...
... After a person is immersed in cold water, a cold shock reaction occurs that causes an uncontrollable heavy breathing (gasp). This is followed by a cold-induced hyperventilation [131] with a longer period of time with high-frequency breathing [63,69]. With prolonged exposure to cold, the respiratory rate is very high and it is assumed that the increased ventilation leads to progressive inefficiency when swimming [132] and respiratory muscle fatigue [125]. ...
Article
Full-text available
Cold water swimming (winter or ice swimming) has a long tradition in northern countries. Until a few years ago, ice swimming was practiced by very few extreme athletes. For some years now, ice swimming has been held as competitions in ice-cold water (colder than 5 °C). The aim of this overview is to present the current status of benefits and risks for swimming in cold water. When cold water swimming is practiced by experienced people with good health in a regular, graded and adjusted mode, it appears to bring health benefits. However, there is a risk of death in unfamiliar people, either due to the initial neurogenic cold shock response or due to a progressive decrease in swimming efficiency or hypothermia.
... Acute oxidative loading due to cold exposure may ultimately lead to long-term antioxidative adaptation which may serve as a potential molecular mechanism resulting in body hardening (11). Certain immune-system components (leukocytes, monocytes, interleukin[IL]-6) have been shown to be increased in winter swimmers implying readiness to combat infection (12). ...
... The cytokine response after thermal stress consisting of sauna followed by swimming in ice-cold water was investigated in habitual and inexperienced winter swimmers (12). In regular winter swimmers, the concentrations of plasma IL-6, leukocytes, and monocytes at rest were significantly higher than in inexperienced subjects. ...
... The authors concluded that thermal stress with sauna followed by swimming in ice-cold water appeared to stimulate both the neuroendocrine and the immune systems, and the results indicate that adaptive mechanisms occur in habitual winter swimmers. The basal levels of several immune response components (leukocytes, monocytes, IL-6) were higher in winter swimmers than in controls, indicating that the immune system is mildly stimulated and probably more prepared to react to an infection (12). ...
Article
Winter swimming is a stressful condition of whole-body exposure to cold water; however, winter swimmers have achieved variable degrees of adaptation to cold. The question arises whether this extreme sport activity has any health benefits or whether it may confer potentially harmful effects. As a form of aerobic exercise, albeit more strenuous when performed in cold water, winter swimming may increase body tolerance to stressors and achieve body hardening. When practiced by individuals who are in good general health adopting a regular, graded and adaptive mode, winter swimming seems to confer cardiovascular (CV), and other health benefits. On the other hand, unaccustomed individuals are at risk of death either from the initial neurogenic cold-shock response, or from progressive decrease of swimming efficiency or from hypothermia. Furthermore, as it may occur with any intense exercise, individuals with evident or occult underlying CV conditions may be more susceptible to adverse effects with provocation of arrhythmias and CV events that may pose a significant health risk. Hence, a stepwise strategy to initiate and build up this recreational activity is recommended to enhance and sustain acclimation, achieve protection from potential risks of cold-water exposure and possibly avail from its promising health benefits. We need more data from prospective studies to better investigate the short- and long-term health consequences of this important recreational activity.
... According to Brenner et al. [24], the severe stress evoked by cold stimulates hemopoiesis in the bone marrow through leukocytosis; in our study, in turn, regular winter swimming and sports pool swimming resulted in lower leukocyte counts, which could be explained by the participants' acclimatization to the given conditions. On the other hand, the decrease in PLT counts observed in our study contrasts with the findings of Dugué and Leppänen [25], who noted increased PLT in inexperienced winter swimmers. This discrepancy likely reflects the effect of regular exposure and acclimatization, which may modulate platelet dynamics differently over time. ...
... Body stimulation through cold water swimming and swimming in a sports pool at 28 • C brings about beneficial adaptive changes in the cardiovascular system, as evidenced in the present study. Dugué and Leppänen [25] indicate that after exposure to sauna, winter swimming, and consecutive thermal stresses, the capacity of isolated mononuclear blood cells to produce IL-1 beta and IL-6 was significantly suppressed in inexperienced subjects but tended to increase in regular winter swimmers, pointing out that habitual winter swimming slightly stimulates the immune system, which leads to the speculation that winter swimmers are better prepared to react to an infection. Teległów et al. [26] also confirmed that regular winter swimming for 4 months positively influenced blood rheological characteristics in males aged 34-53 years, which is indicative of an efficient hemorheological system cooperating with the cardiovascular system. ...
Article
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An important area of health is health promotion. A healthy lifestyle supports health improvement and early prevention of chronic diseases. Stimulation of the body by cold water swimming and swimming in a swimming pool can lead to adaptive changes beneficial for the human cardiovascular system. Within the winter swimming season of 2023/2024, for a period of 5 months, from November to March, once a week, study participants (n = 30; n = 15 females and n = 15 males) from the Krakow Society of Winter Swimmers ‘Kaloryfer’ in Krakow (Poland) practiced winter swimming in cold water (4–5 °C) and swam in the sports pool of the University of Physical Culture in Krakow in water at a temperature of 28 °C. After a full season of winter swimming and swimming pool sessions, both males and females exhibited a tendency towards lower erythrocyte (p = 0.002), leukocyte (p < 0.001), and platelet counts (p < 0.001), as well as an increase in blood plasma viscosity (within normal limits) (p = 0.001), without any changes in blood aggregation or fibrinogen indicators. The remaining morphological indicators and the elongation index demonstrated only limited variation. Winter swimming induces positive changes in blood morphology and rheology.
... NRAP plays a vital role in muscle structure and function, with a mutation at amino acid residue 100 potentially contributing to survival in extreme northern environments [5], and cytokine expression is known to change in mammals exposed to cold [6,7]. For instance, cold exposure has been reported to increase interleukin (IL)-1β and IL-6 levels in cold-resistant humans [8], while in mice, cold stress elevates tumor necrosis factor (TNF)-α and IL-6 levels [9]. ...
... Inflammatory cytokines have been observed in mammals exposed to cold stress [6][7][8][9] and are known to regulate calcium influx by modulating calcium levels within cellular organelles and the nucleus [28,29]. Calcium signaling begins with the influx of calcium from the extracellular space or its release from the endoplasmic reticulum or mitochondria [30]. ...
Article
Full-text available
Background/Objectives: The first camelized mouse model (Nrapc.255ins78) was developed to investigate the mechanisms underlying camels’ adaptation to extreme environments. Previous studies demonstrated that these mice exhibit a cold-resistant phenotype, characterized by increased expression of inflammatory cytokine-related genes in the heart under cold stress. Nebulin-related anchoring protein (NRAP) plays a critical role in organizing myofibrils during cardiomyocyte development. This study builds on prior research by analyzing the heart transcriptomes of Nrapc.255ins78 mice under non-stress conditions to explore the origins of inflammatory cytokine responses during cold exposure. Methods: RNA sequencing was performed on the hearts of 12-week-old male and female Nrapc.255ins78 and wild-type control mice. Results: Differential expression analysis identified 25 genes, including 12 associated with cell cycle and division, all consistently downregulated in Nrapc.255ins78. Notably, the calcium and integrin-binding protein gene (Cib3) was significantly upregulated (FDR < 0.05; p < 0.001). Conclusions: These differentially expressed genes suggest altered calcium dynamics in cardiomyocytes and mechanisms for maintaining homeostasis, supporting the hypothesis that inflammatory cytokines during cold exposure may represent an adaptive response. These findings provide valuable insights into the genetic mechanisms of temperature adaptation in camels and highlight potential pathways for enhancing stress resistance in other mammals.
... Although releasing high levels of reactive oxygen species (ROS) during exercise can harm cellular components, low levels of ROS play multiple regulatory roles in cellular processing, such as controlling gene expression, regulating signaling pathways, and modulating the production of the skeletal muscle force [1,2]. It has also been shown that the inhibition of ROS production blocks the effects of cytokine activity, including the expression of adhesive proteins and decrease in the permeability of the walls of capillaries [3]. On the other hand, a significant increase in ROS generation blocks the proliferation and differentiation of satellite cells in the location of the micro-injury [4]. ...
... The authors noticed an intensification of the expression of the genes that code Il-1β, Il-6 and TNF-α in the case of young volunteers in good physical shape directly after the sports training, while on the other hand, when the training was preceded by the exposure of the organism to low temperatures, a drop in Il-1β and TNF-α expression was observed. Some findings confirm that low temperatures initiate changes in the expression of cytokines linked with non-specific acute phase reactions [3]. It is thought that the reactions between hormones and cytokines that happen during the exposition to cryogenic temperatures may regulate the immunological homeostasis of the organism. ...
Article
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The purpose of the study was to assess the impact of single whole-body cryostimulation (WBC) preceding submaximal exercise on oxidative stress and inflammatory biomarkers in professional, male athletes. The subjects (n = 32, age 25.2 ± 37) were exposed to low temperatures (−130 °C) in a cryochamber and then participated in 40 min of exercise (85% HRmax). Two weeks afterwards, the control exercise (without WBC) was performed. Blood samples were taken before the start of the study, immediately after the WBC procedure, after exercise preceded by WBC (WBC exercise) and after exercise without WBC. It has been shown that catalase activity after WBC exercise is lower in comparison with activity after control exercise. The interleukin 1β (IL-1-1β) level was higher after control exercise than after WBC exercise, after the WBC procedure and before the start of the study (p < 0.01). The WBC procedure interleukin 6 (IL-6) level was compared with the baseline level (p < 0.01). The level of Il-6 was higher both after WBC exercise and after control exercise compared with the level recorded after the WBC procedure (p < 0.05). Several significant correlations between the studied parameters were shown. In conclusion, the changes in the cytokine concentration in the athletes’ blood confirm that body exposition to extremely low temperatures before exercise could regulate the inflammatory reaction course and secretion of cytokines during exercise. A single session of WBC in the case of well-trained, male athletes does not significantly affect the level of oxidative stress indicators.
... In the T group, a signi cant increase in the total number of leukocytes and NEUT was observed in response to both a single sauna bath as well as a series of 10 sessions. This nding was also observed in two additional studies [5,22]. According to Shephard et al. [23], the mechanism responsible for leukocytosis after systemic hyperthermia is an increase in cardiac output and, consequently, an increase in leukocyte demargination. ...
... In the present study, an increase in IL-6 concentration was seen after the 1st and 10th sauna baths. In an experiment by Dugué and Leppänen [22], the reaction to the thermal load of a single sauna bath was examined. A signi cant increase in the concentration of cortisol and IL-6 was observed. ...
Preprint
Full-text available
The aim of the study was to investigate the effect of a Finnish sauna on the immune status markers. Healthy males (20–25 years old) were divided into gropes: the trained (T; n = 10), and the untrained group (N; n = 10). All participants were subjected to 10 baths (3X15-minute with cooled down for 2 minutes). Blood was collected before the 1st and 10th sauna bath, and 10 minutes after their completion. The levels of: cortisol, Il-6, HSP70, IgA, IgG, IgM and blood cells (WBC), leukocyte populations counts: neutrophils, lymphocytes, eosinophils, monocytes, and basophils were determined. No differences were found in the increase in rectal temperature, cortisol and Ig between groups. In response to the 1st sauna bath, a greater increase in HR was observed in the U group. After the last one, the HR value was lower in the T group. The impact on WBC, CD56+, CD3+, CD8+, IgA, IgG and IgM shows a differences in trained and untrained body responses. It seems that in trained people, the non-specific immune response increases, while in untrained, the specific one. Series of sauna baths can be a way of acclimation to high ambient temperatures for athletes and a solution to improve immune response.
... The study was conducted four times during late winter. After testing, a significant increase in the cortisol level was noted, i.e. 61% [18]. Also, an increase in the concentration of interleukin-6 (IL-6) was observed, which is indicative of adaptation of the immune system [18]. ...
... After testing, a significant increase in the cortisol level was noted, i.e. 61% [18]. Also, an increase in the concentration of interleukin-6 (IL-6) was observed, which is indicative of adaptation of the immune system [18]. In our study, only at the beginning of the season in November did we observe a statistically significant increase in cortisol in the sauna and winter swimming group compared with the only winter swimming group. ...
Article
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Abstract Study aim: The aim of the study was to examine the effect of winter swimming and taking a sauna on selected biochemical indicators of the blood.Study material: The participating „Walruses” belonged to the Krakow Walrus club – “The Heaters”. The study group consisted of 20 males, aged 30–45, ‘walrusing’ throughout the whole season from November to March. In order to examine the biochemical indicators of the blood, venous blood samples were drawn from the participants and the following were determined: immuno-globulin levels (IgG, IgA, IgM), the contents of thyroid hormones (FT3, FT4, TSH), and cortisol. On the test day, in November and March, one group of the studies “Walruses” (n = 10) took only cold baths bath for 5 minutes, and the second group of participat-ing “Walruses” (n = 10), on the day of the study, went into a sauna for 10 minutes and took a cold bath for 5 minutes.Study results: At the beginning of the winter swimming season in November, a statistically significant increase in cortisol concentration was found in a group that took the sauna as well as cold baths compared to the group that only took cold baths. A significant increase in IgM concentration at the end of the season in March was also noted for this group. No statistically signifi-cant changes in the level of TSH, FT3, FT4 or cortisol were noticed.Conclusions: This study is the first combining the effects of winter swimming and taking a sauna on the level of immuno-globulin (IgG, IgA, IgM), thyroid hormones (FT3, FT4, TSH) and cortisol.
... Egyptians discovered the invigorating benefits of submerging the body in cold water and Roman soldiers were used to take a quick dip in icy-cold rivers after battles, with recovery purposes. Hippocrates (460-370 BC), the father of the Western medicine, proved that icy-cold water (drunk or used for bathing) had efficacy in multiple medical conditions; he often prescribed ice-cold water as the perfect treatment for relieving pain, oedema and inflammation [2,3]. ...
... Other cold-based practices have also developed in contemporary times, especially in northern countries, e.g. winter swimming: this activity relies on regularly bathing in ice-cold water, during the winter season, based on the belief that it reduces the frequency of sickness and improves the ability to address with daily stresses [3,[9][10][11]. ...
Chapter
Cold treatment is a popular therapy used by anyone in order to relieve or prevent pain and swelling after trauma, inflammatory conditions or any other condition from which pain originates. Nowadays, cold therapy treatments, referable as both whole-body and partial-body cryotherapy, are available and they are based on exposure to extremely cold air (either atmospheric air or liquid nitrogen vapours), with temperature ranging between −110 and −160 °C, in special chambers.
... Furthermore, cold water immersion is a major stress for the body, which is associated with increased cortisol concentrations and the release of cytokines [37], higher concentrations of which are also recorded in asthma. [38] Taking into account all of the above, every asthma patient who would like to try cold water swimming should discuss it with their doctor. ...
Article
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Introduction: Apart from pharmacological treatment, non-pharmacological strategies including physical activity play a significant role in the management of asthma. The aim of this paper is to examine various topics related to swimming and asthma. They include the detailed effect of swimming on asthma control,the potential role of swimming in early childhood asthma development, exercise induced asthma in swimmers as well as the relationship between asthma and cold water swimming. Review methods: This article is based on the literature found in the PubMed Database from the period of 1971-2024 with the use of keywords such as “asthma”, “swimming”, “cold water swimming”, “exercise induced asthma”, “childhood asthma” Description of the state of knowledge: Swimming is a safe form of physical activity for asthma patients.Swimming training enhances aerobic capacity, reduces exercise-induced bronchoconstriction and improves lung function in both pediatric and adult patients. However, there is a concern regarding indoor swimming pools that chlorine can potentially induce airway inflammation. There is research suggesting that early life swimming pool exposure may contribute to the asthma development in atopic children. There is some premise to the thought that cold water swimming may help alleviate asthma symptoms, but it also carries many risks.Swimming is a major cause of exercise induced asthma in professional athletes. Conclusions: Alongside appropriate pharmacological treatment, swimming is a valuable strategy in asthma management in both pediatric and adult asthma patients. The risks of chlorinating pools are still not known to outweigh the benefits of swimming for asthmatics. Further research should be carried out on safety of early swimming in atopic children. Cold water swimming should also be evaluated in terms of safety and potential benefits for asthma patients.
... Interestingly, we observed both RORγt and T-bet positive γδ T cells in cold swimmers (Fig. 6B). In a study by Dugué and Leppänen, habitual winter swimmers showed decreased LPS-induced release of IL-1β and IL-6 [61]. LPS is recognized via TLR4 on antigen-presenting cells; however, stimulation of γδ T cells with LPS increased their proliferation and cytotoxic potential [62]. ...
Article
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The mammalian body possesses remarkable adaptability to cold exposure, involving intricate adjustments in cellular metabolism, ultimately leading to thermogenesis. However, cold‐induced stress can impact immune response, primarily through noradrenaline‐mediated pathways. In our study, we utilized a rat model subjected to short‐term or long‐term mild cold exposure to investigate systemic immune response during the cold acclimation. To provide human relevance, we included a group of regular cold swimmers in our study. Our research revealed complex relationship between cold exposure, neural signaling, immune response, and thermogenic regulation. One‐day cold exposure triggered stress response, including cytokine production in white adipose tissue, subsequently activating brown adipose tissue, and inducing thermogenesis. We further studied systemic immune response, including the proportion of leukocytes and cytokines production. Interestingly, γδ T cells emerged as possible regulators in the broader systemic response, suggesting their possible contribution in the dynamic process of cold adaptation. We employed RNA‐seq to gain further insights into the mechanisms by which γδ T cells participate in the response to cold. Additionally, we challenged rats exposed to cold with the Toll‐like receptor 2 agonist, showing significant modulation of immune response. These findings significantly contribute to understanding of the physiological acclimation that occur in response to cold exposure.
... 13 Moreover, cytokines can modulate the response of an organism to stimuli by activating the hypothalamic-pituitary-adrenal axis. 26 The final stage of acute inflammatory response is dominated by mediators involved in suppressing inflammation, 27 during which they control the spread of inflammation, limit inflammatory responses, and facilitate the final stage of muscle repair. 16 ...
Article
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Physical activity has a positive effect on human health and emotional well-being. However, in both amateur and professional athletes, training poses a risk of acute or chronic injury through repetitive overloading of bones, joints, and muscles. Inflammation can be an adverse effect of intense exercise caused by several factors including oxidative stress. The present narrative review summarizes current knowledge on inflammatory markers induced by physical exercise. Post-exercise recovery may reduce inflammatory responses and is key to effective training and adaptation of muscle tissues to sustained physical exertion.
... The likely cause of the discrepancies in the findings could be attributed to different research protocols. Some participants only immersed in icy water [20,50], some engaged in static swimming (remaining motionless in cold water for an extended period) [51,52], and some were long-distance swimmers, whose training (dynamic swimming in cold water) can last up to 6-8 h [31]. ...
Article
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Our study aimed to explore the potential positive effects of cold water exercise on mitochondrial biogenesis and muscle energy metabolism in aging rats. The study involved 32 male and 32 female rats aged 15 months, randomly assigned to control sedentary animals, animals training in cold water at 5 ± 2 °C, or animals training in water at thermal comfort temperature (36 ± 2 °C). The rats underwent swimming training for nine weeks, gradually increasing the duration of the sessions from 2 min to 4 min per day, five days a week. The results demonstrated that swimming in thermally comfortable water improved the energy metabolism of aging rat muscles (increased metabolic rates expressed as increased ATP, ADP concentration, TAN (total adenine nucleotide) and AEC (adenylate energy charge value)) and increased mRNA and protein expression of fusion regulatory proteins. Similarly, cold-water swimming improved muscle energy metabolism in aging rats, as shown by an increase in muscle energy metabolites and enhanced mitochondrial biogenesis and dynamics. It can be concluded that the additive effect of daily activity in cold water influenced both an increase in the rate of energy metabolism in the muscles of the studied animals and an intensification of mitochondrial biogenesis and dynamics (related to fusion and fragmentation processes). Daily activity in warm water also resulted in an increase in the rate of energy metabolism in muscles, but at the same time did not cause significant changes in mitochondrial dynamics.
... Similarly, the near-ocean is also a site for pollution, collisions and in the complex third spaces of the beach, more unhealthy social encounters as well ( Bell et al., 2018 ). As a very diff erent strand, and one not considered in this chapter, there are also specifi cally scientifi c explorations of swimming bodies from sports science, physiology and psychology that focus on identifi able and measurable changes in bodily capacities and the benefi ts of physical exercise to improve human fi tness and strength ( Britton et al., 2018 ;Dugu é and Lepp ä nen, 2010 ;Leonard et al., 2018 ). ...
... 27 Deep-breathing techniques and routine cold exposure may improve ANS functionality and impact inflammatory processes linked to depression. 34,58 Therefore, the health benefits evidenced through the three-part practice may be attributable to mindful awareness cultivation through meditation, augmented with physiological adaptations enabled via breathing techniques and cold exposure. ...
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Context: Qigong, a mind-body practice in traditional Chinese medicine (TCM), can improve cognitive functions, emotional balance, attention, multitask management, stress-coping, and well-being. One limitation of Qigong research is a lack of adequate controls. Objective: The current study intended to evaluate whether a single 5-min practice of a White Ball (WB) Qigong exercise could improve the perceptual auditory attention, divided and focused, in adults and whether obtaining potential effects would require a minimum level of training. Design: The research team designed a prospective, randomized, placebo-controlled, and single-blinded study. Setting: The study took place at the Institute of Biomedical Sciences (ICBAS) at the University of Porto in Porto, Portugal. Participants: Participants were 55 students at the University of Porto, 30 of whom were students attending the second year of medical school at ICBAS with no experience in Qigong and 25 of whom were students in the specialization and Master's programs in TCM with experience in Qigong. Intervention: The research team randomly distributed the 30 participants without experience into two groups, a negative control group (n = 15), who watched a wildlife video for 5 min in an orthostatic position, and a positive control group , the verum Qigong group (n = 15), who participated in 5 min of Qigong practice. The Qigong-practitioner group (n = 25), the intervention group, participated in the same 5-min Qigong, doing it with expertise. Outcome measures: The study measured reaction time (RT) under two experimental conditions, one an auditory RT task and the second an auditory RT task with visual distraction. The procedure was constant for all the studied groups. Results: Postintervention, the reaction time (RT) in the negative control and the verum Qigong groups hadn't changed significantly (P > .05), while that of the Qigong-practitioner group had decreased significantly, with shorter RTs under the two experimental conditions, with P = .006 for the auditory RT and P = .003 for the auditory + visual distraction. Qigong may induce a conditioning effect that comes with regular practice. Conclusions: The WB Qigong had a positive effect on the AA mechanism, with a significant reduction in RT. The results support the importance of practice to achieve positive effects. People with neurodevelopmental disorders, such as autism and ADHD, struggle every day for sensory integration of AA mechanisms. Qigong can be taught and easily learned from the age of 2 years until senior ages, and it's a safe and very low-cost intervention that deserves to be researched further in clinical trials. These potential benefits of Qigong should be confirmed by future studies.
... For instance, in the blood of regular winter swimmers, the concentrations of plasma IL-6, monocytes, and leukocytes are remarkably higher than that of inexperienced swimmers [12] . ...
... Complementary to chemical hormetins, hormetic reactions can be elicited by a series of physical stimuli, also referred as "physical hormetins". One of these accessible and effective hormetic stressors is thermal stress generated by high and low temperatures, which elicits a series of positive outcomes, mostly via heat-shock factors/proteins [5,[50][51][52][53][54][55][56][57]. ...
Article
Psycho-biological resilience is considered one of the most important factors in the epigenetics of aging. Cell senescence exhibits a series of possible biochemical derangements concerning mitochondria, proteasome, genome and membranes. Research has shown that resilience can be acquired through hormesis, a set of conservative and adaptive processes based on biphasic dose-response to specific mild stressors, such as fasting, intake of polyphenols, exercising, physical and chemical stress and mental engagement. These stimuli were shown to elicit beneficial cellular metabolic pathways, such as sirtuin activation, mechanistic target of rapamycin and insulin growth factor-1 downregulation, nuclear related factor 2 upregulation and autophagy. The complex of these resilience-building processes plays a documented role in longevity. Mitochondria are regarded as one of the core actors of aging processes and represent the main target of hormetic approaches [mitohormesis]; furthermore, the influence of the mind on mitochondria, and thus on the balance of health and disease has been recently established , leading to the so-called mitochondria psychobiology. Hence, psychologic and physical stress that reflects on these organelles may be regarded as a relevant factor in cell senescence and thus the proposed “mitoresilience“ denomination may be pertinent within the biomedical science of aging. Finally, the quantification of individual resilience is becoming increasingly important in aging science and the investigation of the autonomic nervous system through heart rate variability [HRV] proved to be a valid method to quantify this parameter. In conclusion, an integrated approach targeting hormetic pathways to improve psycho-physical resilience [namely mitoresilience], supported by the monitoring of HRV may represent a valuable option in longevity medicine.
... Beginners, the researcher used physiological tests (pulse, pressure, vital capacity), physical tests, skill, measurements related to blood, and the study showed that the proposed aerobic and anaerobic program led to an improvement in all research variables and an improvement in the level of performance. (9) The researchers prefer these results to the effectiveness of the training probability (of different intensities) on the response of the immune system, which is represented in the aggregate of here the numbers of white blood cells, which rose significantly after the effort directly and this is due to the effect of that physical effort (running on the running walk) by the mobilization of large numbers of cells White to cope with the changes that occurred in the body's systems as a result of that effort. ...
... According to Brenner et al. [21], the fall in core body temperature resulting from cold exposure led to a consistent and statistically significant mobilization of circulating cells, an increase in NK cell activity, and elevations in circulating IL-6 concentrations. The adaptation of mechanisms under conditions of an increased heat loss in the immune system is evidenced by the study of Dugue et al. [27], who noted that regular swimming in winter resulted in an increase in interleukins (IL-6) compared with untrained subjects. This is supported by the results obtained by the study of Castellani et al. [28], who observed significant increases in ADH, cortisol, and interleukin-6, which are the most active cytokines involved in immune mechanisms. ...
Article
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Regular exposure to a cold factor—cold water swimming or ice swimming and cold air—results in an increased tolerance to cold due to numerous adaptive mechanisms in humans. Due to the lack of scientific reports on the effects of extremely low outdoor temperatures on the functioning of the human circulatory system, the aim of this study was to evaluate complete blood count and biochemical blood indices in multiple Guinness world record holder Valerjan Romanovski, who was exposed to extremely cold environment from −5 °C to −37 °C for 50 days in Rovaniemi (a city in northern Finland). Valerjan Romanovski proved that humans can function in extremely cold temperatures. Blood from the subject was collected before and after the expedition. The subject was found to have abnormalities for the following blood indices: testosterone increases by 60.14%, RBC decreases by 4.01%, HGB decreases by 3.47%, WBC decreases by 21.53%, neutrocytes decrease by 17.31%, PDW increases by 5.31%, AspAT increases by 52.81%, AlAT increase by 68.75%, CK increases by 8.61%, total cholesterol decreases by 5.88%, HDL increases by 28.18%. Percentage changes in other complete blood count and biochemical indices were within standard limits. Long-term exposure of the subject (50 days) to extreme cold stress had no noticeable negative effect on daily functioning.
... This practice involves alternating exposures to heated rooms followed by immersion in cold water or snow. 9 In Europe, the use of cold and hot water spas as centres of healing dates back at least as far as the Roman period. In 43 AD, having conquered most of southern Britain, the Romans set about building spa resorts. ...
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Background An increasing volume of anecdotal and scientific evidence suggests that mood may be enhanced following swimming in cold water. The exact mechanisms responsible are largely unknown, but may include the effects of exercise from swimming and the effects of cold. This study examined the effect on mood following immersion in cold water, where swimming was not the primary activity. Methods The Profile of Mood States (POMS) questionnaire was completed by 64 undergraduate students. The following week, 42 participants completed up to 20-min immersion (18ʹ36ʺ ± 1ʹ48ʺ) in cold sea water (13.6°C). Twenty-two participants acted as controls. The POMS was completed immediately following the cold-water immersion by both groups. Results The cold-water immersion group showed a significant decrease, with a large effect size, of 15 points from 51 to 36, compared to 2 points in the control group, 42 to 40. Positive sub-scales increased significantly in the cold-water immersion group (Vigour by 1.1, and Esteem-Related Affect by 2.2 points) and negative sub-scales showed significant reductions (Tension by 2.5, Anger 1.25, Depression 2.1, Fatigue 2.2, and Confusion 2.8 points). The control showed no significant change except for depression, which was significantly higher after the period by 1.6 points. Conclusion Cold-water immersion is a well-tolerated therapy that is capable of significantly improving mood in young, fit, and healthy individuals. A key aim of this study was to control for the effects of swimming as a mechanism responsible for the improvement in mood which has been shown in previous studies. Thus, the change in mood evidenced in this study was not due to physical activity per se. Consequently, the hypothesis that cold in and of itself can improve mood is supported.
... Les effets de la nage en eaux froides sur le bienêtre et la douleur sont bien documentés [1,2] . De nouvelles techniques de cryostimulation (CCE, CCP) ont récemment été mises au point et consistent à exposer le corps entier (tête incluse pour la CCE et exclue pour la CCP) à un froid extrême pendant une courte période [3] . ...
Technical Report
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La Cryothérapie Corps Entier (CCE) et la Cryothérapie Corps Partiel (CCP) – regroupées sous le terme de Cryostimulation – sont de nouvelles techniques consistant à exposer le corps entier (tête exclue pour la CCP) à un froid extrême pendant une courte période (typiquement 3 minutes à -110 °C). Après exposition, les patients font état de certains bienfaits dont une diminution des douleurs, des gonflements au niveau des articulations et du niveau d’inflammation, accompagnée d’une relaxation musculo-squelettique et d’une augmentation de l’amplitude des mouvements. La cryostimulation est également efficace pour soulager les symptômes d’anxiété et de dépression ainsi que pour accélérer la récupération musculaire des athlètes. Toutefois, des preuves scientifiques solides de ces bénéfices restent à apporter. Une intensification des travaux de recherche est nécessaire pour identifier les variables clés induisant les bénéfices de la cryostimulation et pour définir et adapter les protocoles de soin (fréquence et paramètres d’exposition notamment). De plus, les questions de sécurité liées à l’utilisation de la cryostimulation sont essentielles, en particulier la prise en compte des contre-indications médicales et des risques physiques comme l’anoxie. Cela passe aussi par la certification des opérateurs et des dispositifs cryogéniques utilisés. https://iifiir.org/fr/fridoc/la-cryotherapie-corps-entier-cryostimulation-39-lt-sup-gt-e-lt-sup-gt-note-142805
... The effects of cold-water swimming on well-being and pain are well documented [1,2] . New cryo therapy techniques (WBC, PBC) have recently been developed and consist of exposing the whole body (head included for WBC and excluded for PBC) to extreme cold for a short period [3] . ...
Article
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Whole-Body Cryotherapy (WBC) and Partial-Body Cryotherapy (PBC) – grouped under the term Cryostimulation – are new techniques consisting in exposing the whole body (head excluded for PBC) to extreme cold for a short period of time (typically 3 minutes at -110 °C). After exposure, patients experienced decreased soreness, oedema and inflammation, as well as musculoskeletal relaxation and increased range of motion. Cryostimulation is also effective in alleviating symptoms of anxiety and depression and accelerating muscle recovery in athlets. However, solid scientific evidence of these benefits has yet to be provided. An intensification of research is necessary to identify the key variables inducing the benefits of cryostimulation and to define and adapt treatment protocols (frequency and exposure parameters in particular). In addition, safety issues related to the use of cryostimulation are essential, in particular the consideration of medical contraindications and physical risks such as anoxia. This also requires certification of the operators and cryogenic devices used.
... Cryotherapy consists in exposing the body to cold temperature. It is traditionally implemented in the form of ice packs applied onto the body or cold-water immersion where part or the entire body is immersed (Dugué and Leppanen 2000). Whole-body and partial-body cold air cryostimulation (WBC and PBC) are now presented as modern cryotherapy techniques with an ever-growing popularity in the sport and medical sphere (Bleakley et al. 2014). ...
Article
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PurposeA predominance of parasympathetic drive is observed following cold exposure. Such modulation of the autonomic nervous system (ANS) is associated with faster post-exercise recovery. Within this context, whole-body cryotherapy (WBC) has been spreading in sport medicine, though the optimal temperature and frequency are unclear. The aim of this study was to examine the effects of different cryotherapy conditions on the sympathovagal balance.Methods Forty healthy males were randomly assigned into five different groups (− 110 °C, − 60 °C, − 10 °C, control temperature [≃ 24 °C]) and undertook 5 WBC sessions over 5 consecutive days. Cardiac autonomic activity was assessed through heart rate variability (HRV) using power density of high frequency (HF), root-mean square difference of successive R–R intervals (RMSSD) and sympathovagal balance (LF/HF). Systemic sympathetic activity was assessed via circulating blood catecholamines.ResultsMean weekly RMSSD (pre: 48 ± 22 ms, post: 68 ± 29 ms) and HF (pre: 607 ± 692 ms2, post: 1271 ± 1180 ms2) increased (p < 0.05) from pre to post WBC, only in the − 110 °C condition. A rise in plasma norepinephrine was found after the first − 110 °C WBC session only (pre: 173 ± 98, post: 352 ± 231 ng L−1, p < 0.01); whereas, it was not significant after the 5th session (pre: 161 ± 120, post: 293 ± 245 ng L−1, p = 0.15).Conclusion These results suggest that one − 110 °C WBC exposure is required to stimulate the ANS. After five daily exposures, a lower autonomic response was recorded compared to day one, therefore suggesting the development of physiological habituation to WBC.
... 16,17 This seems in agreement with the existing literature about cold water immersion, which reports beneficial effects on health in regular winter swimmers, thanks to the same adaptive physiologic mechanisms that increase tolerance to cold. 2 For example, cold water immersion can induce a higher basal activity of antioxidant enzymes such as superoxide-dismutase and catalase, 18 while thermal stress (a hot sauna bath and then a cold water swimming) can improve the readiness and the efficacy of the stress and immune response (higher LPS-induced cytokine secretion) in habitual winter sea bathers. 19 Moreover, cold exposure can stimulate brown adipose tissue (BAT), a thermogenic tissue that could increase energy expenditure and thus be beneficial for dysmetabolic diseases such as obesity, type 2 diabetes and metabolic syndrome. 20À22 However, this is a much-debated topic: while open water bathing does induce BAT, this only accounts for a very small percentage of total dietary fatty acid metabolism (0.3% after 4-week cold acclimation), which is not of clinical significance. ...
Article
Context : Many people claim winter sea bathing gives them energy and health. According to the psychoneuroendocrinoimmunology (PNEI) paradigm, the stress response elicited by cold water immersion could indeed induce several beneficial psychophysical alterations. Objective : To determine the effects of winter sea bathing on psychological wellbeing, stress and immune markers. Design : A cross-sectional study. Participants : 228 people, between 19 and 88 years, including107 winter sea bathers and 121 controls. Main Outcome Measures : A battery of questionnaires was administered to assess sociodemographic characteristics, self-perception of mental and physical heath, the number, duration and intensity of Upper Respiratory Tract Infections (URTIs) in the last year, and Big Five personality traits.17 winter sea bathers and 15 controls (mean age 67 years) were further examined to evaluate physiological health, underwent one ear-nose-throat (ENT) examination, and provided saliva samples for measurements of biological markers (cortisol, sIgA, IL-1β, IL-6). Results : Winter sea bathing was associated with lower levels of self-reported stress and higher wellbeing. The ENT examinations did not reveal signs of URTIs in winter sea bathers, who exhibited significantly higher levels of salivary sIgA compared to controls. Neither salivary IL-1β nor cortisol levels were significantly different between the two groups. Conclusions : Winter sea bathers (even the elderly) had a perception of higher wellbeing and reported better health: thus, they appeared to take advantage of potential distress (cold water exposure) to improve their health.
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There is a growing interest in weight loss in today’s world. Environmental factors are the main contributor behind the rapidly spreading obesity during pandemic. Exercise and diet are two controllable elements that significantly effect on energy balance., The use of cold application such as cold-water immersion, cold abdominal pack, balneotherapy, cold exposure, water drinking, steam, and sauna sessions, has shown a positive impact in weight management. This review explains the mechanism and various types of hydrotherapy applications managing weight through thermogenesis and non-shivering thermogenic pathways, which involve the brown adipose tissue, and dependent on uncoupling protein 1 (UCP1) in the inner mitochondrial membrane. Hence the present literature provides insight into use of hydrotherapy applications for future direction in weight management.
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Healthy aging is a crucial goal in aging societies of the western world, with various lifestyle strategies being employed to achieve it. Among these strategies, hydrotherapy stands out for its potential to promote cardiovascular and mental health. Cold water therapy, a hydrotherapy technique, has emerged as a lifestyle strategy with the potential capacity to evoke a wide array of health benefits. This review aims to synthesize the extensive body of research surrounding cold water therapy and its beneficial effects on various health systems as well as the underlying biological mechanisms driving these benefits. We conducted a search for interventional and observational cohort studies from MEDLINE and EMBASE up to July 2024. Deliberate exposure of the body to cold water results in distinct physiological responses that may be linked to several health benefits. Evidence, primarily from small interventional studies, suggests that cold water therapy positively impacts cardiometabolic risk factors, stimulates brown adipose tissue and promotes energy expenditure—potentially reducing the risk of cardiometabolic diseases. It also triggers the release of stress hormones, catecholamines and endorphins, enhancing alertness and elevating mood, which may alleviate mental health conditions. Cold water therapy also reduces inflammation, boosts the immune system, promotes sleep and enhances recovery following exercise. The optimal duration and temperature needed to derive maximal benefits is uncertain but current evidence suggests that short-term exposure and lower temperatures may be more beneficial. Overall, cold water therapy presents a potential lifestyle strategy to enhancing physical and mental well-being, promoting healthy aging and extending the healthspan, but definitive interventional evidence is warranted.
Chapter
Metabolomics is a powerful tool that encompasses the complete set of metabolites involved in various metabolic pathways, providing valuable insights into an organism’s physiological status. The external environment plays a crucial role in shaping the metabolome of living organisms. Metabolomics is particularly useful for investigating how external factors, such as diet, lifestyle, drugs, thermal stress, and other environmental exposures, can influence an individual’s metabolic profile and overall health. When an organism experiences thermal stress, its metabolic pathways can be altered to maintain homeostasis, repair damage, and ensure survival. This chapter highlights the role of metabolomics in identifying metabolites involved in the response to thermal stress, as well as reviews specific metabolic pathways affected by cold stress and the underlying physiological responses mediated by cold.
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Objective Hydrotherapy is a traditional prevention and treatment strategy. This study’s aim is to systematically review all available randomised controlled trials (RCTs) investigating clinical effects of hydrotherapy according to Kneipp which is characterised by cold water applications. Methods RCTs on disease therapy and prevention with Kneipp hydrotherapy were included. Study participants were patients and healthy volunteers of all age groups. MEDLINE (via PubMed), Scopus, Central, CAMbase, and opengrey.eu were systematically searched through April 2021 without language restrictions and updated by searching PubMed until April 6th 2023. Risk of bias was assessed using the Cochrane tool version 1. Results Twenty RCTs (N=4247) were included. Due to high heterogeneity of the RCTs, no meta-analysis was performed. Risk of bias was rated as unclear in most of the domains. Of 132 comparisons, 46 showed significant positive effects in favour of hydrotherapy on chronic venous insufficiency, menopausal symptoms, fever, cognition, emotional function and sickness absenteeism. However, 81 comparisons showed no differences between groups and 5 were in favour of the respective control group. Only half of the studies reported safety issues. Conclusion Although RCTs on Kneipp hydrotherapy seem to show positive effects in some conditions and outcomes, it remains difficult to ascertain treatment effects due to the high risk of bias and heterogeneity of most of the considered studies. Further high-quality RCTs on Kneipp hydrotherapy are urgently warranted. PROSPERO registration number CRD42021237611.
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Exercise has been proven to benefit human health comprehensively regardless of the intensity, time, or environment. Recent studies have found that combined exercise with a cold environment displays a synergistical beneficial effect on cardiovascular system compared to exercise in thermoneutral environment. Cold environment leads to an increase in body heat loss, and has been considered a notorious factor for cardiovascular system. Exercise in cold increases the stress of cardiovascular system and risks of cardiovascular diseases, but increases the body tolerance to detrimental insults and benefits cardiovascular health. The biological effects and its underlying mechanisms of exercise in cold are complex and not well studied. Evidence has shown that exercise in cold exerts more noticeable effects on sympathetic nervous activation, bioenergetics, anti-oxidative capacity, and immune response compared to exercise in thermoneutral environment. It also increases the secretion of a series of exerkines, including irisin and fibroblast growth factor 21, which may contribute to the cardiovascular benefits induced by exercise in cold. Further well-designed studies are needed to advance the biological effects of exercise in cold. Understanding the mechanisms underlying the benefits of exercise in cold will help prescribe cold exercise to those who can benefit from it.
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Sowohl Hitze als auch Kälte können helfen, die Gesundheit zu stabilisieren. Thermische Reize wirken sich positiv auf die Infektabwehr aus, indem sie den Körper „abhärten“. Sauna, Eisbaden und kleinere hydrotherapeutische Kaltreize haben verschiedene Wirkungen auf das Immunsystem. Eine Reihe von Studien belegen ihren Nutzen für die Abwehrkräfte bereits.
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Background The aim of the study was to investigate the effect of a Finnish sauna on the immune status parameters. The hypothesis was that hyperthermia would improve immune system’s functioning by changing the proportion of lymphocyte subpopulations and would activate heat shock proteins. We assumed that the responses of trained and untrained subjects would be different. Material and methods Healthy men (20–25 years old) were divided into groups: the trained (T; n = 10), and the untrained group (U; n = 10). All participants were subjected to 10 baths (each one consisted of: 3 × 15-minute exposure with cooled down for 2 min. Body composition, anthropometric measurements, VO2 peak were measured before 1st sauna bath. Blood was collected before the 1st and 10th sauna bath, and 10 min after their completion to asses an acute and a chronic effect. Body mass, rectal temperature and heart rate (HR) were assessed in the same time points. The serum levels of cortisol, Il-6, HSP70 were measured with use of ELISA method, IgA, IgG and IgM by turbidimetry. White blood cells (WBC), leukocyte populations counts: neutrophils, lymphocytes, eosinophils, monocytes, and basophils were determined with use of flow cytometry as well as T-cell subpopulations. Results No differences were found in the increase in rectal temperature, cortisol and immunoglobulins between groups. In response to the 1st sauna bath, a greater increase in HR was observed in the U group. After the last one, the HR value was lower in the T group. The impact of sauna baths on WBC, CD56+, CD3+, CD8+, IgA, IgG and IgM was different in trained and untrained subjects’ responses. A positive correlation between the increase in cortisol concentrations and increase in internal temperatures after the 1st sauna was found in the T (r = 0.72) and U group (r = 0.77), between the increase in IL-6 and cortisol concentrations in the T group after the 1st treatment (r = 0.64), between the increase in IL-10 concentration and internal temperature (r = 0.75) and between the increase in IL-6 and IL-10 (r = 0.69) concentrations, also. Conclusions Sauna bathing can be a way to improve the immune response, but only when it is undertaken as a series of treatments.
Chapter
The Covid-19 pandemic which started in 2020 has brought many changes to people's daily live. It influenced the quality and possibilities of spending free time. Physical activity was restricted, which had an impact on both physical and mental health. The specificity of that time is reflected in the statistics collected all around the world - it shows the number of people whose well-being and physical condition have drastically decreased. The search for alternatives to sports in sport objects and out-door facilities has gained popularity, which is why many people have become convinced of exercising at home. The consideration is focusing on finding difficulties that were posed by home isolation in active leisure and their consequences.
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Physical activity has a positive effect on human health and well-being, but intense exercise can cause adverse changes in the organism, leading to the development of oxidative stress and inflammation. The aim of the study was to determine the effect of short-term cold water immersion (CWI) and a sauna bath as methods of postexercise regeneration on the indicators of inflammation and oxidative damage in the blood of healthy recreational athletes. Forty-five male volunteers divided into two groups: ‘winter swimmers’ who regularly use winter baths (n = 22, average age 43.2 ± 5.9 years) and ‘novices’ who had not used winter baths regularly before (n = 23, mean age 25 ± 4.8 years) participated in the study. The research was divided into two experiments, differing in the method of postexercise regeneration used, CWI (Experiment I) and a sauna bath (Experiment II). During Experiment I, the volunteers were subjected to a 30-min aerobic exercise, combined with a 20-min rest at room temperature (RT-REST) or a 20-min rest at room temperature with an initial 3-min 8 °C water bath (CWI-REST). During the Experiment II, the volunteers were subjected to the same aerobic exercise, followed by a RT-REST or a sauna bath (SAUNA-REST). The blood samples were taken before physical exercise (control), immediately after exercise and 20 min after completion of regeneration. The concentrations of selected indicators of inflammation, including interleukin 1β (IL-1β), interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 8 (IL-8), interleukin 10 (IL-10), transforming growth factor β1 (TGF-β1) and tumor necrosis factor α (TNF-α), as well as the activity of indicators of oxidative damage: α1-antitrypsin (AAT) and lysosomal enzymes, including arylsulfatase A (ASA), acid phosphatase (AcP) and cathepsin D (CTS D), were determined. CWI seems to be a more effective post-exercise regeneration method to reduce the inflammatory response compared to a sauna bath. A single sauna bath is associated with the risk of proteolytic tissue damage, but disturbances of cellular homeostasis are less pronounced in people who regularly use cold water baths than in those who are not adapted to thermal stress.
Chapter
The coronavirus pandemic has caused the public to have increased problems with both physical and mental activity. In order to prevent this, people have started to look for ways to spend their free time. One of them is resting in the countryside and in agro-tourism areas. Due to the great interest in this form of leisure and its financial benefits, people started to look for types of activities that can be practiced in rural areas. This review presents the most important effects of the pandemic on health and innovative ideas for spending leisure time in nature, away from the city, and in agritourism areas.
Chapter
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Winter swimming is a practice, which benefits both, physical and mental health. This activity is easy to access and is recently gaining popularity, which is related to the prevailing pandemic. When ice swimming, certain rules regarding the choice of bathing place and the time of staying in the water must be strictly observed. Good technique is essential to avoid health complications. Practicing this activity is associated with reducing the risk of civilization diseases, such as insulin resistance or thrombotic diseases. Before starting practicing, however, it is necessary to make sure that there are no contraindications against it.
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Background: Children born in the fall and winter are at increased risk for developing atopic dermatitis and food allergy. Because these seasons are associated with low temperatures, we hypothesized that exposure to low temperatures may compromise keratinocyte differentiation and contribute to skin barrier dysfunction. Objective: We examined whether low temperature causes skin barrier dysfunction. Methods: Primary human epidermal keratinocytes (HEK) were differentiated in 1.3 mmol CaCl2 media and cultured at different temperatures. The cells were transfected with transient receptor potential cation channel subfamily V member 1 (TRPV1) or STAT3 small interfering RNA (siRNA) to examine the effects of these gene targets in HEK exposed to low temperature. Gene expression of TRPV1, epidermal barrier proteins, and keratinocyte-derived cytokines were evaluated. Organotypic skin equivalents were generated using HEK transfected with control or TRPV1 siRNA and grown at 25°C or 37°C. Transepidermal water loss (TEWL) and levels of epidermal barrier proteins were evaluated. Results: Filaggrin (FLG) and loricrin (LOR) expression, but not keratin (KRT)-1 and KRT-10 expression, was downregulated in HEK incubated at 25°C, while TRPV1 silencing increased intracellular Ca2+ influx (keratinocyte differentiation signal) and enhanced the expression of epidermal differentiation proteins. IL-1β and thymic stromal lymphopoietin induced by low temperature inhibited FLG expression in keratinocytes through the TRPV1/STAT3 pathway. Moreover, low temperature-mediated inhibition of FLG and LOR was recovered, and TEWL was decreased in organotypic skin transfected with TRPV1 siRNA. Conclusion: TRPV1 is critical in low temperature-mediated skin barrier dysfunction. Low temperature exposure induced thymic stromal lymphopoietin, an alarmin implicated in epicutaneous allergen sensitization.
Article
Winter swimming is a complex procedure that simultaneously includes the effects of cold, water itself, physical activity, and the climate factor. All these elements are used in thermal medicine in a milder form. They also have a lot in common with Kneipp hardening therapy. In winter swimming, belonging to extreme sports, extremely strong stimuli act simultaneously. Winter swimming positively affects the cardiorespiratory system, complete blood count, musculoskeletal system, endocrine system, immune system, the skin, metabolic processes, and the mental sphere. Empirically, many beneficial effects of winter swimming have been discovered, but there is very little scientific research showing this procedure’s mechanisms of action. Hence, they are often based on hypotheses. The mechanisms of action of winter swimming on complete blood count and the organism’s oxidative processes are best explained. However, the explanation of the mechanisms of action is mostly based on research conducted in cryotherapy. To obtain beneficial health effects, it is necessary to prepare properly for winter swimming and comply with the entire process’s rules, from preparation, through the treatment itself, to behavior after the procedure. In recent years, handbooks and guides have appeared in Poland that contain practical tips on the winter swimming procedure.
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We assessed the effects of a 3-min partial-body cryostimulation (PBC) exposure-where the whole body is exposed to extreme cold, except the head-on cognitive inhibition performance and the possible implications of parasympathetic cardiac control and cerebral oxygenation. In a randomized controlled counterbalanced cross-over design, eighteen healthy young adults (nine males and nine females) completed a cognitive Stroop task before and after one single session of PBC (3-min exposure at − 150 °C cold air) and a control condition (3 min at room temperature, 20 °C). During the cognitive task, heart rate variability (HRV) and cerebral oxygenation of the prefrontal cortex were measured using heart rate monitoring and near-infrared spectroscopy methods. We also recorded the cerebral oxygenation during the PBC session. Stroop performance after PBC exposure was enhanced (562.0 ± 40.2 ms) compared to pre-PBC (602.0 ± 56.4 ms; P < 0.042) in males only, accompanied by an increase (P < 0.05) in HRV indices of parasympathetic tone, in greater proportion in males compared to females. During PBC, cerebral oxygenation decreased in a similar proportion in males and females but the cerebral extraction (deoxyhemoglobin: ΔHHb) remained higher after exposure in males, only. These data demonstrate that a single PBC session enhances the cognitive inhibition performance on a Stroop task in males, partly mediated by a greater parasympathetic cardiac control and greater cerebral oxygenation. The effects of PBC on cognitive function seem different in females, possibly explained by a different sensitivity to cold stimulation.
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The study was undertaken to determine whether psychological stress influences immunobiological functions and is an important preanalytical factor to be considered in connection with blood specimen collection. Two kinds of stress were applied, the Stroop colour conflict test and the thrill of a novice about to make the first jump with a parachute. In both test situations, the level of the stress indicators cortisol or anti-diuretic hormone rose significantly. The concentrations of the cytokines studied did not change significantly. However, in the parachute test significant positive correlations were found, e.g. between the changes of cortisol and C-reactive protein and between anti-diuretic hormone and interleukin-1 beta. This suggests that there is an interaction between the endocrine and the immune systems in the response to a psycological stress.
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Accumulating data indicate that interleukins can activate the hypothalamic-pituitary-adrenal (HPA) axis. We evaluated the effect of human recombinant interleukin-3 (IL-3) and interleukin-6 (IL-6) on cortisol secretion from adult human adrenocortical cells in primary culture. IL-3 and IL-6 (100 μg/L) equipotently stimulated basal cortisol secretion approximately 5-fold. The stimulatory effect was significant after 12 h (p < 0.01) and maximum cortisol levels were induced after 48 h. In contrast to ACTH, which significantly induced cAMP levels in parallel to its steroidogenic effect, IL-3 or IL-6 had no significant effect on cAMP. Furthermore, we showed that specific inhibition of the cyclooxygenase pathway by indomethacin completely blocked the steroidogenic effect of IL-6 while the effect of IL-3 was not affected. In contrast, coincubation with nordihydroguaiaretic acid—a specific inhibitor of the lipoxygenase system—abolished IL-3 stimulated steroidogenesis but had no effect on IL-6 stimulated cortisol secretion. These findings indicate that IL-3 and Il-6 directly stimulate the steroidogenesis at the adrenal level through activation of different, cAMP-independent pathways. While the stimulatory effect of IL-6 on cortisol secretion from adult human adrenocortical cells seems to be mediated through the cyclooxygenase pathway, the effect of IL-3 on adrenocortical cortisol secretion is dependent on the lipoxygenase pathway.
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The concentrations of blood components are influenced by a number of pre-analytical factors, the importance of which varies [1]. Therefore it is necessary to standardize the specimen collection, as was done by the Committee on Reference Values of the Scandinavian Society for Clinical Chemistry and Clinical Physiology, which in 1975 published its recommendation on the production of reference values in clinical chemistry [2]. It was the very first recommendation of its kind. Since then, new information has accumulated, and it has become necessary to revise the part concerning the preparation of subjects for blood collection, the collection procedure itself, and the subsequent handling of the specimen. Also, The International Federation of Clinical Chemistry (Expert Panel on Theory of Reference Values) has produced its own recommendation [3]. The recommendation described below replaces pp. 39-44 of the former Scandinavian recommendation [2]. The procedure described below is designed for the collection of specimens for the measurement of the majority of components in blood and specimen collection from the cubital vein is described. It can be easily adapted for the collection of blood from other vessels [4]. Certain laboratory investigations require a special protocol. In that case, the preparation of the subject prior to and during specimen collection as well as the procedure itself should be described in sufficient detail to permit reproduction by adequately trained personnel. In any project designed to produce reference values the same protocol for the preparation of individuals and specimen collection should be used throughout the project. The protocol should be described in detail. Thus, it is not satisfactory to state only that the present recommendation was followed. Each section of the recommendation is followed by a check list for points which should be taken into account.
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The aim of this study is to investigate the presence of several interleukins in saliva and how their concentrations may be modified after physical stress. The effects of one kind of somatic stress (sauna heat) on the concentrations of salivary cytokines were studied using ELISA assay. In addition, saliva cortisol was assayed. Fourteen volunteers participated in this study. Each subject attended one control and one stress session which took place at the same hour on different days. Saliva was collected on the control day immediately after a 15-min rest period in a seated position (R1), and again after an additional 30-min seated period (R2). On the test day, saliva was collected after 15 min of sitting (S1) and 30 min later (S2) following exposure to the heat of a sauna (90°C, 10 min, 40 per cent humidity). We found that saliva contains the multifunctional polypeptide cytokines interleukin-1β, tumour necrosis factor alpha and the receptor for interleukin-2 with the basal mean concentrations (geometric mean; SD in parenthesis) of 172 (106; 148) ng/l, 46 (20; 67) ng/l and 9 (6; 7) pM, respectively. Interleukin-6 was detectable in only 60 per cent of the specimens investigated. Interleukin-2 and the receptor for interleukin-6 were not detectable. We examined the statistical differences between the ratio R2/R1 (the changes which occurred during the resting period) and S2/S1 (the changes during the exposure to heat). We observed a significantly higher S2/S1 ratio for the tumour necrosis factor alpha in males, compared to the control ratio (2.5±2.4 versus 0.7±0.7,N=6,p<0.05 using the Wilcoxon signed rank test). Our results indicate that a situation which induced an elevated body temperature was associated with a rise in the concentration of the salivary tumour necrosis factor alpha.
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The adrenaline release from the adrenal medulla increases during exercise, but at a given absolute work intensity the magnitude of this response is less pronounced in endurance trained vs sedentary individuals most likely due to a lower sympathetic stimulation of the adrenal medulla. However, when trained and untrained subjects are compared at identical relative work loads as well as in response to numerous non-exercise stimuli. endurance trained athletes have a higher epinephrine secretion capacity compared to sedentary individuals. This indicates a development of a so-called "sports adrenal medulla" as a result of a long term adaptation of an endocrine gland to physical training. Such an adaptation is parallel to adaptations taking place in other tissues like skeletal muscle and the heart. and can be advantageous in relation to both exercise performance in the competing athlete and cause a biological rejuvenation in relation to aging.
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Delayed type hypersensitivity (DTH) reactions are antigen-specific, cell-mediated immune responses which, depending on the antigen involved, mediate beneficial (resistance to viruses, bacteria, fungi, and certain tumors) or harmful (allergic dermatitis, autoimmunity) aspects of immune function. We have shown that acute stress administered immediately before antigenic challenge results in a significant enhancement of a skin DTH response in rats. A stress-induced trafficking or redeployment of leukocytes to the skin may be one of the factors mediating this immunoenhancement. Here we investigate the effects of varying the duration, intensity, and chronicity of stress on the DTH response and on changes in blood leukocyte distribution and glucocorticoid levels. Acute stress administered for 2 h prior to antigenic challenge, significantly enhanced the DTH response. Increasing the duration of stress from 2 h to 5 h produced the same magnitude enhancement in cutaneous DTH. Moreover, increasing the intensity of acute stress produced a significantly larger enhancement of the DTH response which was accompanied by increasing magnitudes of leukocyte redeployment. In contrast, chronic stress suppressed the DTH response when it was administered for 3 weeks before sensitization and either discontinued upon sensitization, or continued an additional week until challenge, or extended for one week after challenge. The stress-induced redeployment of peripheral blood lymphocytes was attenuated with increasing exposure to chronic stress and correlated with attenuated glucocorticoid responsivity. These results suggest that stress-induced alterations in lymphocyte redeployment may play an important role in mediating the bi-directional effects of acute versus chronic stress on cell-mediated immunity in vivo.
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A radioimmunoassay (RIA) for arg8-vasopressin (AVP) in unextracted human plasma was based on a sensitive anti-AVP rabbit antiserum, inhibition of enzymatic damage to [125I]AVP and AVP, and the use of an individual plasma blank, to correct for interference of plasma factors with the RIA. Sensitivity was 0.4 pg of synthetic AVP detected, corresponding to 1.2 pg/ml of AVP in human plasma. Recovery of AVP added to pooled plasma was 94 +/- 9.3% (mean +/- S.D.) in the low range (AVP, 2.8 pg/ml added) and 106 +/- 11.7% in the high range (45.0 pg/ml added). In 26 healthy, ambulatory subjects on ad lib, water intake, plasma AVP concentration was 2.0 +/- 1.22 pg/ml in the supine position and in 28 healthy subjects, 6.2 +/- 4.3 pg/ml in the upright position. Water loading suppressed the plasma AVP concentration. Smoking caused increased plasma AVP in 3 subjects despite water loading.
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The response to systemic infection includes the coordinated appearance of hepatic acute-phase proteins, the production of which may be influenced by a counterregulatory hormonal background. This study sought to assess the potential for hypercortisolemic conditions to influence fibrinogen kinetics and other acute-phase protein responses in humans with endotoxemia. Eleven hospitalized healthy male volunteers underwent two separate determinations of fibrinogen kinetics, one baseline and one after administration of endotoxin (2 ng/kg intravenously; lot EC-5). Seven volunteers were studied without hormonal manipulation and four in the presence of a hypercortisolemic background (hydrocortisone infusion, 3 micrograms/kg/min). Fibrinogen fractional synthetic rates were estimated from the incorporation of orally administered 15N-glycine, and fibrinogen, C-reactive protein, cortisol, tumor necrosis factor-alpha, and interleukin-6 levels were also determined. The presence of an antecedent hypercortisolemic background resulted in an attenuated interleukin-6 response, as well as decreased fibrinogen synthesis and C-reactive protein appearance. The current data suggest that glucocorticoid hormonal influences are of importance in the regulation of endotoxin-induced cytokine and acute-phase protein responses.
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The ability of an individual to mount defense responses to infection depend in part on the capacity to produce cytokines such as interleukin 1 (IL-1) and tumor necrosis factor (TNF). The specialized equipment, labor intensity, and sterile practice required for the standard in vitro evaluation of cytokine production can make such evaluation impractical in some clinical situations. We report a method for stimulating whole blood to produce cytokines that can be implemented in laboratories without tissue culture facilities and requires minimal sample preparation. IL-1 beta and TNF alpha production in whole blood samples was stimulated with endotoxin and/or phytohemagglutinin in standard EDTA-containing vacuum collection tubes. After incubation, plasma was removed and frozen for later assay. Comparison of this whole blood method with isolated mononuclear cell cultures indicated a significant correlation for IL-1 beta production (r = 0.746, P = 0.005). This technique also produced the newly described cytokine, IL-1 receptor antagonist. We conclude that the whole blood method is an acceptable alternative to isolated cell culture methods for measuring IL-1 beta in situations that preclude the standard in vitro approach.
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The generation of tumour necrosis factor (TNF) and tissue factor activity in lipopolysaccharide (LPS) stimulated blood were studied in 25 healthy subjects before and after physical exercise of different intensities. Of the subjects a group of 9 were athletes who trained once to twice every day of the week, a second group of 8 exercised 3-7 times a week, and a third group of 8 exercised 4-5 times a month. The production of TNF in freshly drawn LPS stimulated blood in heparin, drawn from top athletes at rest was significantly lower than in the other subjects. The LPS induced concentrations of TNF-alpha of 2.73 (SEM 1.05) ng.ml-1 in the blood of the top athletes compared to 5.08 (SEM 0.7) ng.ml-1 and 7.6 (SEM 1.6) ng.ml-1, respectively, in the other two groups. The group that trained the least had the highest values. Immediately after exercise, the monocytes appeared to be less responsive to LPS stimulation, as a reduction of 47%-48% was observed in the top athletes and in the other group of well-trained individuals. The group that trained the least, which was also subjected to the least stressful exercise, had a 33% reduction in TNF production. Within 6 h the TNF concentration was back to pre-exercise values. Within 6 h the TNF concentration was back to pre-exercise values.(ABSTRACT TRUNCATED AT 250 WORDS)
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We investigated whether interleukin-6 (IL-6) could cause the release of corticosterone by a direct interaction with the adrenal gland. Primary cultures of rat adrenal glands were obtained by dispersion with collagenase and incubated for 24 h with different doses of IL-6. Levels of corticosterone were measured by competitive protein binding assay. A significant (P less than 0.025) dose-dependent increase in corticosterone levels was seen at all doses used. Time course experiments demonstrated that IL-6 stimulated corticosterone release over a period of 24 h but not after 12 or 3 h. The stimulation of adrenal cells with different doses of ACTH1-24 and 40 U/ml of IL-6 showed a synergistic effect when IL-6 was combined with low concentrations of ACTH1-24 (2 and 20 pmol/l). This effect was not evident at higher doses. Our results suggest that IL-6 may act at different levels of the hypothalmic pituitary adrenal axis. Moreover the finding of a synergistic effect with ACTH1-24 indicates that IL-6 could play a role in the long term response to stress.
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We have examined the effect of dexamethasone (DM) and cortisol on the production of interleukin (IL)6 from the murine macrophage cell line RAW264.9, human monocytes, human endothelial cells and the human fibroblast cell line FS4. In RAW264.9 cells DM in the concentration range 10(-9) M to 10(-6) M inhibited the lipopolysaccharide (LPS)-induced production of IL6 by 10% to 90%. Cortisol had a similar effect, but was about 25 times less potent than DM. Also, when 10(-6) M of DM was added to the cultures after addition of LPS, it completely inhibited the residual 24-h production of IL6. Corresponding to the effect on IL6 production, DM (10(-6) M) reduced the mRNA levels for IL6 in the RAW264.9 cells. The glucocorticoid analogue RU 486 competes with DM and cortisol for the glucocorticoid receptor and reversed the inhibitory effect of DM, demonstrating that DM exerts its effect via the glucocorticoid receptor. DM also had an inhibitory effect on LPS-stimulated IL6 production in freshly isolated human monocytes, and on IL 1-stimulated IL6 production in human endothelial cells and FS4 fibroblasts. These results demonstrate that DM via a receptor-mediated mechanism inhibits IL6 production at the transcriptional level, and this may contribute to the anti-inflammatory and immunosuppressive effect of glucocorticoids.
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Eight healthy young men were studied during three periods of heat exposure in a Finnish sauna bath: at 80 degrees C dry bulb (80 D) and 100 degrees C dry bulb (100 D) temperatures until subjective discomfort, and in 80 degrees C dry heat, becoming humid (80 DH) until subjective exhaustion. Oral temperature increased 1.1 degrees C at 80 D, 1.9 degrees C at 100 D and 3.2 degrees C at 80 DH. Heart rate increased about 60% at 80 D, 90% at 100 D and 130% at 80 DH. Plasma noradrenaline increased about 100% at 80 D, 160% at 100 D and 310% at 80 DH. Adrenaline did not change. Plasma prolactin increased 2-fold at 80 D, 7-fold at 100 D and 10-fold at 80 DH. Blood concentrations of the beta-endorphin immunoreactivity at 100 D, adrenocorticotropic hormone (ACTH) at 100 D and 80 DH, growth hormone at 100 D and testosterone at 80 DH also increased, but cortisol at 80 D and 100 D decreased. The plasma prostaglandin E2 and serum thromboxane B2 levels did not change. Patterns related to heat exposure were observed for heart rate, plasma noradrenaline, ACTH and prolactin in the three study periods.
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Nine winter swimmer men were exposed to: (A) sauna and ice water immersion; (B) sauna and 15 degrees C shower; (C) sauna and room temperature; (D) head-out ice-water immersion and room temperature. The exposures were repeated and ended with a recumbent recovery. The initial, post-exposure and post-recovery concentrations of plasma ACTH, serum cortisol, serum melatonin, plasma norepinephrine and plasma epinephrine were determined. ACTH and cortisol indicated a slightly increased post-exposure level. Melatonin concentration did not change. Post-exposure norepinephrine levels increased (P less than 0.05) from the initial. Post-exposure epinephrine indicated a tendency to elevated levels with a nearly doubled (P less than 0.05) concentration in experiment A. The tendency toward enhanced ACTH and cortisol secretion and sympathetic activity shown by increased catecholamine secretion suggest that the winter swimming practice may raise the pain threshold and develop a potential for improved cold tolerance, possibly by nonshivering thermogenesis.
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The cardiovascular responses to cold were studied in a group of 28 subjects who enjoyed swimming in ice-cold water in winter ("ice-bears"). History and clinical examination had revealed no abnormalities except hypertension (180/105 mm Hg) in 1, while 3 other subjects had a diastolic value of 95 mm Hg. Systolic blood-pressure increased significantly while the subjects were waiting undressed in cold air in the cabin by the pond. Neither immersion nor swimming in the ice-cold water caused further increase in systolic blood-pressure, and diastolic blood-pressure showed only a modest rise. 4 min later, blood-pressure had returned to control values. Electro and vector cardiographic signs remained unchanged. Although very high pressures were recorded in several subjects, no signs of left ventricular hypertrophy or of cardiovascular of cerebrovascular damage could be detected.
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Abnormalities in the hypothalamic-pituitary-adrenal axis (HPA) have been the most consistently demonstrated biological markers in depressive illness. Numerous other neuroendocrine disturbances have also been described, including blunted clonidine-induced growth hormone release and blunted fenfluramine-induced prolactin release. These disturbances are generally interpreted in terms of monoaminergic receptor dysfunction. The theory presented here suggests that chronic stress which activates the HPA will in certain susceptible people produce changes in central monoamines. The high level of glucocorticoid receptors on such central neurons is postulated as mediating the alterations. Thus monoamine abnormalities, rather than being a core aetiological feature of depression, are seen as secondary to HPA overdrive.
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Neuroendocrine response was investigated during and after a single 20 min bath in sauna (80 degrees C) in a group of 8 healthy men and 8 healthy women. In an additional group of 8 young men, the dynamics of plasma ACTH and cortisol levels were studied during a 30 min sauna exposure (90 degrees C). This dynamic study showed a biphasic response of plasma cortisol which decreased during the initial phase of sauna bath (15 min) and increased thereafter, reaching its maximum 15 min after the end of bathing. Maximal increase in plasma ACTH levels occurred 15 min earlier. In the first sauna exposed group the increase in body temperature was the same (about 2 degrees C) in both sexes. Nevertheless, the elevation in plasma ACTH concentration was significantly more pronounced in women than in men. In the plasma collected at the end of sauna bath inside the sauna room, a significant rise in both adrenaline and noradrenaline levels was found. Though the catecholamine responses were similar in both groups, the increase in heart rate during sauna bath was significantly higher in women. Sauna-induced prolactin release was also more pronounced in women compared with men. Thus hyperthermia induced by sauna exposure resulted in a more pronounced neuroendocrine activation in women compared with men. Moreover, it is evident that repeated blood sampling is necessary to reveal the sauna-induced activation of some hormonal systems.
Article
The concentrations of blood components are influenced by a number of preanalytical factors, the importance of which varies [1]. Therefore it is necessary to standardize the specimen collection, as was done by the Committee on Reference Values of the Scandinavian Society for Clinical Chemistry and Clinical Physiology, which in 1975 published its recommendation on the production of reference values in clinical chemistry [2]. It was the very first recommendation of its kind. Since then, new information has accumulated, and it has become necessary to revise the part concerning the preparation of subjects for blood collection, the collection procedure itself, and the subsequent handling of the specimen. Also, The International Federation of Clinical Chemistry (Expert Panel on Theory of Reference Values) has produced its own recommendation [3]. The recommendation described below replaces pp. 39-44 of the former Scandinavian recommendation [2]. The procedure described below is designed for the collection of specimens for the measurement of the majority of components in blood and specimen collection from the cubital vein is described. It can be easily adapted for the collection of blood from other vessels [4]. Certain laboratory investigations require a special protocol. In that case, the preparation of the subject prior to and during specimen collection as well as the procedure itself should be described in sufficient detail to permit reproduction by adequately trained personnel. In any project designed to produce reference values the same protocol for the preparation of individuals and specimen collection should be used throughout the project. The protocol should be described in detail. Thus, it is not satisfactory to state only that the present recommendation was followed. Each section of the recommendation is followed by a check list for points which should be taken into account.
Article
Glucocorticoids, as part of their physiological role in the control of inflammatory and immune processes, suppress the expression of IL-1 and other cytokines. We have found a dose-dependent inhibition by dexamethasone (10 nM to 10 microM) of mRNA levels of the recently cloned IL-1 receptor antagonist (IL-1ra) in endotoxin-stimulated human monocytes. At the same concentrations, both dexamethasone and cortisol inhibited the secretion of IL-1ra. These inhibitory effects were reversed by blocking glucocorticoid receptors with the specific antagonist RU 38486, but not by adding exogenous IL-1, even up to 100 ng/ml, to the monocytes. A similar inhibition of IL-1ra mRNA and protein secretion was found in monocytes obtained after dexamethasone administration in vivo. In addition, we observed parallel increases in glucocorticoid and IL-1ra levels following endotoxin administration to normal volunteers. Our results show that glucocorticoids shut down not only IL-1 but also IL-1ra expression, ruling out induction of IL-1ra as part of the glucocorticoid antiinflammatory mechanism. The control of the delicate immunoregulatory balance of the IL-1/IL-1ra system during endotoxemia underscores the physiological importance of glucocorticoids in the final control of immune responses.
Article
Glucocorticoids, as a part of their physiological role in the control of inflammatory and immune processes, suppress the expression of interleukin-1 (IL-1) and other cytokines. Human monocyte IL-1 receptor antagonist (IL-1ra) messenger ribonucleic acid (mRNA) expression and protein secretion are inhibited by dexamethasone. We have now further studied the regulation of IL-1ra by the major physiological human glucocorticoid, cortisol. We found that cortisol incubation induced a decrease in IL-1ra mRNA expression and a significant inhibition of IL-1ra protein secretion in cell cultures of human peripheral monocytes stimulated with the bacterial endotoxin lipopolysaccharide (LPS). Oral administration of 276 mumol cortisol to normal subjects also decreased LPS-induced IL-1ra synthesis in cultured monocytes. By coincubating the monocytes with either the mineralocorticoid antagonist spironolactone or the glucocorticoid receptor antagonist RU 38486, the in vitro cortisol-induced inhibition of LPS-stimulated IL-1ra secretion was partially reversed. The mineralocorticoid aldosterone exerted a significant decrease in LPS-induced monocyte IL-1ra secretion in vitro, which was blocked by coincubation with spironolactone. In addition, the expression of mineralocorticoid receptor mRNA in human monocytes was observed by PCR of reversed transcribed RNA. Our results further indicate that corticosteroids physiologically control the IL-1/IL-1ra system during inflammatory or immune processes. Moreover, we provide evidence that, in addition to a glucocorticoid receptor-mediated effect, the mineralocorticoid receptor is involved in the inhibition of monocyte IL-1ra secretion by cortisol.
Article
Although plasma corticosteroid concentrations can be measured accurately, the biological effect on the target tissue is uncertain. The availability of an accurate measure of corticosteroid sensitivity would potentially clarify the putative roles of endogenous glucocorticoids in illnesses such as inflammatory disease and obesity and allow evaluation of an additional regulatory level of glucocorticoid action. To measure corticosteroid sensitivity, we developed an assay based on the inhibition by dexamethasone (Dex) of lipopolysaccharide (LPS)-induced Interleukin-6 (IL-6) production and release in whole unseparated blood in vitro. LPS induced a dose-dependent increase in IL-6 concentrations up to 34 +/- 6.6 ng/mL, reaching plateau levels after 8 h, whereas Dex dose dependently inhibited LPS-induced IL-6 production. Involvement of the glucocorticoid receptor in this response was supported by abrogation of Dex (10(-7) mol/L) inhibition of IL-6 production by the glucocorticoid receptor antagonist RU 38486. To determine whether corticosteroid sensitivity is a dynamic phenomenon, we subjected healthy males to a graded quantifiable exercise associated with increases in plasma ACTH and cortisol. Before exercise, 3 x 10(-8) mol/L Dex inhibited LPS-induced IL-6 production in vitro; after exercise, 3 x 10(-8) and 10(-7) mol/L Dex were unable to inhibit IL-6 production. We conclude that Dex suppression of LPS-induced IL-6 production is an effective means of determining corticosteroid sensitivity, and that corticosteroid sensitivity in human subjects is a dynamic, rather than a static, phenomenon.