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Immune system of cold exposed an cold adapted humans

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Abstract

The aim of this study was to investigate whether or not the human immune system can be activated by a noninfectious stimulus, thereby improving the physiological status of the individual. The effect of a single cold water immersion (14 degrees C for 1 h) on the immune system of athletic young men, monitored immediately after immersion, was minimal. With the continuation of the cold water immersions (three times a week for a duration of 6 weeks) a small, but significant, increase in the proportions of monocytes, lymphocytes with expressed IL2 receptors (CD25) and in plasma tumour necrosis factor alpha content was induced. An increase in the plasma concentrations of some acute phase proteins, such as haptoglobin and haemopexin, was also observed. After 6 weeks of repeated immersions a trend towards an increase in the plasma concentrations of IL6 and the amount of total T lymphocytes (CD3), T helper cells (CD4), T suppressor cells (CD8), activated T and B lymphocytes (HLA-DR) and a decrease in the plasma concentration of alpha 1-antitrypsin was observed. Concentrations of IL1 beta, neopterin, C-reactive protein, orosomucoid, ceruloplasmin, macroglobulin, immunoglobulins (IgG, IgM, IgA) and C3, C4 components of the complement, as well as the total number of erythrocytes, leucocytes, granulocytes and neutrophils showed no significant changes after the repeated cold water immersions. It was concluded that the stress-inducing noninfectious stimuli, such as repeated cold water immersions, which increased metabolic rate due to shivering the elevated blood concentrations of catecholamines, activated the immune system to a slight extent. The biological significance of the changes observed remains to be elucidated.
... There are several studies, which have investigated how the immune system responds to regular noninfectious stress stimuli after CWI. For example, in one study [81] involving 6 weeks of regular 1 hour CWI (14°C), increases in plasma concentration of interleukin (IL)-6, total T lymphocytes (CD3), T helper cells (CD4), T suppressor cells (CD8), activated T and B lymphocytes (HLA-DR) were found. In the same study, they found a decrease in the plasma concentration of alpha 1-antitrypsin. ...
... 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]. ...
... 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]. Some research was based on subjects not involved in cold-water swimming, for example, as a post-exercise treatment following sports activities [55,[96][97][98]. ...
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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.
... One possible interpretation of these results is that the response of the thyroid to cold exposure may involve inhibition of thyroidal hormone secretion by vasoconstriction, leading to reduced production of T 3 and T 4 . Serum IgG, IgA, and IgM production was not significantly different in grazing Mongolian sheep between the warm and cold seasons, and similar findings have been reported for humans [32]. ...
... Cytokines have marked effects on the bidirectional communication between the neuroendocrine and immune systems, and there are several proinflammatory cytokines, such as IL-1β and IL-6, which are generally considered to be indicators of inflammation that reflect the immunity of the host [32,33]. Human data have demonstrated that cold stress can increase IL-2 cytokine levels [32]. ...
... Cytokines have marked effects on the bidirectional communication between the neuroendocrine and immune systems, and there are several proinflammatory cytokines, such as IL-1β and IL-6, which are generally considered to be indicators of inflammation that reflect the immunity of the host [32,33]. Human data have demonstrated that cold stress can increase IL-2 cytokine levels [32]. Similarly, in our study, the IL-2 level was much greater in the cold season than in the warm season. ...
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Mongolian sheep are characteristically cold-tolerant. However, their cold adaptive processes, such as the physiological feedback adjustments that occur during the cold season, remain unexplored. Therefore, the present study aimed to evaluate the physiological adaptations of Mongolian sheep in cold plateau environments. A comparative analysis of the serum biochemical parameters, immune response, antioxidant capacity, and glucose and lipid metabolism of grazing Mongolian sheep in the cold and warm seasons was conducted. The results showed that in the cold season, the glucose and lipid metabolism and thermogenesis of the grazing Mongolian sheep were notably enhanced. Moreover, the immune responses were stimulated by increased levels of cytokines, such as IL-2, IL-1β, and IL-6, during the cold season. However, the antioxidant defense system was damaged; this damage was mainly characterized by decreased activity of antioxidant enzymes and an increased level of MDA during the cold season. Overall, glucose metabolism, lipid metabolism, thermogenesis, and immune responses were stimulated to meet the requirements of organismal metabolic regulation to enable grazing Mongolian sheep to physiologically adapt to cold climatic conditions.
... Immunoglobulins play a major role in the humoral immune response and are a heterogeneous group of immune system proteins. Reduced incidence of various diseases in cold-hardened individuals has been linked to higher plasma IgA levels [32]. Janský et al. [32] showed no significant changes after the repeated cold-water immersions for IL-6, immunoglobulins (IgG, IgM, IgA), C-reactive protein. ...
... Reduced incidence of various diseases in cold-hardened individuals has been linked to higher plasma IgA levels [32]. Janský et al. [32] showed no significant changes after the repeated cold-water immersions for IL-6, immunoglobulins (IgG, IgM, IgA), C-reactive protein. It was concluded that the stress-inducing noninfectious stimuli, such as repeated cold-water immersions, increased metabolic rate due to shivering and the elevated blood catecholamine concentrations of catecholamines, activating the immune system to a slight extent. ...
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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.
... Hypothermic stress as a result of exposure to cold environments and cold water has been shown to increase circulating catecholamine concentration and subsequently influence lymphocyte mobilisation (Jansky et al. 1996;Castellani et al. 2002). Our results found that PBC stimulated a greater change in numbers of CD16 + NK cells and CD8 + T cells in comparison to CWI, suggesting a larger catecholamine response after PBC could result in a morepronounced mobilisation of lymphocytes than CWI. ...
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Partial body cryotherapy (PBC) is proposed to alleviate symptoms of exercise-induced muscle damage (EIMD) by reducing associated inflammation. No studies have assessed acute PBC exposure on peripheral blood mononuclear cell mobilisation or compared these with cold water immersion (CWI), which may inform how PBC impacts inflammatory processes. This trial examined the impact of a single PBC exposure on circulating peripheral blood mononuclear cells compared to CWI or a control. 26 males were randomised into either PBC (3 min at − 110 to − 140 °C), CWI (3 min at 9 °C), or control (3 min at 24 °C), with blood samples, heart rate, and blood pressure taken before and after exposure. Cytometric analysis determined that CD8⁺ T-cell populations were significantly elevated after treatments, with PBC increasing CD8⁺ T cells to a greater degree than either CWI or CON. Natural killer cell counts were also elevated after PBC, with the increase attributed specifically to the CD56loCD16⁺ cytotoxic subset. This provides the first evidence for the effect of PBC exposure on redistribution of immune cells. An increase in circulating leukocyte subsets such as CD8⁺ T cells and CD56loCD16⁺ natural killer cells suggests that PBC may induce a transient mobilisation of lymphocytes. PBC may thus enable a more efficient trafficking of these cells from the circulation to the site of initial cellular insult from exercise, potentially accelerating the process of cellular recovery. This provides novel evidence on the use of PBC as a recovery treatment and may also have applicability in other clinical settings involving the recovery of damaged skeletal muscle.
... Under chronic cold stress, the IL-2 and IL-10 contents were increased in the spleen and bursa of Fabricius and decreased in the thymus. It was reported that cold stress enhanced IL-2 cytokine levels in humans (Jansky et al. 1996). In our study, compared with normal temperature, the cold temperature stimulation of G2 and G3 increased the expression levels of IL-2 and IL-4 in the spleen of both Altay lambs and Hu lambs, and the levels of IL-4 in G3 were signi cantly higher than those in G2 and G1. ...
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The aim of the present study was to explore the effects of cold stress at different levels on hormone contents, immune function, and heat-producing genes expression in Altay and Hu lambs. The lambs were randomly divided into three experimental groups maintained under different temperature conditions (G2: -20±3℃ and G3: -30±3℃) for acute cold stress (6 h, 24 h) and chronic cold stress (4 d, 12 d, 24 d) and one thermoneutral group was maintained at the control temperature (G1:15±2℃). The levels of leptin in the serum of two breeds was lower in the cold stress group than in G1 (P<0.01), and the norepinephrine levels was higher in the cold stress groups than in the thermoneutral group (P<0.01). The levels of epinephrine in the serum of Altay and Hu lambs dynamically fluctuated in the G2 and G3. The glucagon levels of the Hu lambs were significantly higher in G2 and G3 than in G1 (P<0.01). The glucagon levels of Altay lambs were significantly decreased in G2 compared with G1 (P<0.01). The insulin levels in the serum of the Altay lambs were significantly lower in the stress group than in G1 (P<0.01). The insulin levels in the serum of Hu lambs tended to irregularly fluctuation in the experimental groups compared with the G1. Histopathological examination showed that the intestinal tissues of the cold stress group were seriously injured. The mRNA expression levels of IL-2, IL-4, IL-10, IL-12 and IFN-β in the spleen varied at different time periods after cold stress, but were overall higher in the cold stress group than in G1 (P<0.01). After cold stimulation, the expression of uncoupling protein 1 and hormone-sensitive lipase in fat tissues showed dynamic changes, but were increased significantly compared with control group (P<0.01). These results suggested that cold stress induced the endocrine system and influenced the immune function of the spleen. The increased expression of HSL and UCP1 may play a role in energy metabolism in the response of animals to cold stress. This work add an important data for the studding the ability of animal to adapt with the colder regions.
Article
Introduction Optimal mental state and physical fitness are crucial factors affecting training of military personnel. Incorporating components aimed at improving mental status and physical composition of soldiers into training programmes can lead to better outcomes. Previously, cold exposure has been used to promote human health in multiple ways, with a plethora of reported benefits. Thus, the aim of this study was to examine the effect of regular cold exposure on the psychological status and physical composition of healthy young soldiers in the Czech Army. Methods A total of 49 (male and female) soldiers aged 19–30 years were randomly assigned to one of the two groups (intervention and control). The participants regularly underwent cold exposure for 8 weeks, in outdoor and indoor environments. Life Satisfaction Questionnaire and InBody 770 device were used to evaluate life satisfaction and body composition, respectively. Zung Self-Rating Anxiety Scale was used to assess anxiety produced by cold exposure. Results Theoretical and practical training in cold immersion in the winter did not induce anxiety. Regular cold exposure led to a significant (p=0.045) increase of 6.2% in self-perceived sexual satisfaction compared with the pre-exposure measurements. Furthermore, considerable increase (6.3% compared with the pre-exposure period) was observed in self-perceived health satisfaction; the change was borderline significant (p=0.052). In men, there was a reduction in waist circumference (1.3%, p=0.029) and abdominal fat (5.5%, p=0.042). Systematic exposure to cold significantly lowered perceived anxiety in the entire test group (p=0.032). Conclusions Cold water exposure can be recommended as an addition to routine military training regimens. Regular exposure positively impacts mental status and physical composition, which may contribute to the higher psychological resilience. Additionally, cold exposure as a part of military training is most likely to reduce anxiety among soldiers.
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To evaluate the effects of intermittent mild cold stimulation (IMCS) on the intestinal immune function and anti-cold stress ability of broilers after acute cold stress, two hundred forty healthy one-day-old Ross 308 male broilers were randomly divided into three groups (CS0 group, CS3 group and CS6 group), with five replicates in each group and sixteen broilers in each replicate. The mRNA expression levels of cytokines and Toll-like receptors (TLRs) in the duodenum and jejunum were detected at the end of cold stimulation (36 d), two weeks after recovery (50 d), and after acute cold stress (Y6). In addition, the mRNA and protein expression levels of heat shock proteins (HSPs) were measured before and after acute cold stress. The experimental data were statistically processed using one-way ANOVA and Duncan's multiple comparisons. The results showed that the mRNA expression levels of IL2, IL8, IFN γ, TLR7 and TLR21 in the duodenum were significantly higher in the CS6 group than in the CS0 and CS3 groups at 36 d (P < 0.05). In the jejunum, the mRNA expression levels of IL2 and IFN γ were significantly higher in the CS6 group than in the CS0 and CS3 groups (P < 0.05). All TLR levels in the jejunum were significantly lower in the CS3 group than in the CS0 and CS6 groups at 36 d (P < 0.05). In the jejunum, there were no significant differences between the CS3 group and the CS0 group in any cytokines or TLRs (except TLR21) at 14 d after IMCS (P > 0.05). After 6 h of acute cold stress, the duodenum in the CS0 and CS6 groups was affected by cold stress, and the mRNA expression levels of IL6 and IL8 were significantly decreased compared to levels at 50 d (P < 0.05), while levels in the CS3 group remained stable (P > 0.05). In the CS3 group, most TLR mRNA expression levels in the jejunum were not significantly different before and after acute cold stress (P > 0.05). Compared with 50 d, the expression level of HSP mRNA in the jejunum in the CS3 group was relatively stable compared to that in the CS0 and CS6 groups after acute cold stress (P > 0.05). At the protein level, the HSP60 expression level in the duodenum and HSP40, HSP60 and HSP70 expression levels in the jejunum were significantly higher in the CS3 group than in the CS0 and CS6 groups after acute cold stress (P < 0.05). In conclusion, cold stimulation training at 3 °C lower than the conventional feeding temperature can enhance the immune function of broilers and improve their adaptability to cold environments. Moreover, the 3 h intermittent cold stimulation program made broilers more resistant to cold stress.
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Cancer immunotherapies emerge as promising strategies for restricting tumor growth. The tumor microenvironment (TME) has a major impact on the anti‐tumor immune response and on the efficacy of the immunotherapies. Environmental factors play critical roles in affecting overall energy metabolism and can also impact the TME. Recent studies have linked changes in the ambient temperature with particular immunometabolic reprogramming and anti‐cancer immune response in laboratory animals. Here, we describe the energetic balance of the organism during change in temperature, and link this to the immune alterations that could be of relevance for cancer, as well as for other human diseases. We highlight the contribution of the gut microbiota in modifying this interaction. We describe the overall metabolic response and underlying mechanisms of tumorigenesis in mouse models at varying ambient temperatures and shed light on their potential importance in developing therapeutics against cancer.
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Background Outdoor swimming is increasingly popular, with enthusiasts claiming benefits to mental health. However, there is limited research into its effectiveness as an intervention for people with depression and/or anxiety. We aimed to establish recruitment rates and explore potential benefits, for a sea swimming course offered to people with depression and/or anxiety. Methods This was a singlearm, unblinded feasibility study. 61 participants, were recruited to an eight-session sea-swimming course. Attendance rates were recorded. Self-administered questionnaires were completed at baseline, post-course and at three-month follow-up. Free-text descriptions of thoughts about the course were collected using surveys, and 14 participants kept a diary. Results 53 participants (47 female, 5 male, 1 non-binary) were included in the final analysis. Overall attendance was 90.1%. There were reductions showing large effect (between d = 1.4 to 1.7) in the severity scores of both depression and anxiety between the beginning and end of the course. While severity scores marginally increased at three-month follow-up, a reduction from baseline scores for depression, anxiety (d = 1.2 and 1.4, respectively) and functioning scores (d = 0.8) remained. The qualitative analysis identified that ‘confronting challenges', ‘becoming a community’ and ‘appreciating the moment’ were key to the impact, or the 'mechanisms', that resulted in participants experiencing the 'outcomes' of ‘immediate positive changes in mood’, ‘improved mental and physical health’ and ‘increased motivation to swim’. Conclusions This study provides preliminary support for the engagement and acceptability of sea swimming as a novel intervention for depression and/or anxiety. Participants reported positive changes in mental health, indicating the intervention's potential as a public health resource. There was a clear gender difference, which requires further exploration. Larger scale trials are warranted.
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Objectives Although cold exposure is commonly believed to be causally related to acute viral respiratory infections, its effect on the immune system is largely unexplored. In this study, we determined transcript levels of a large panel of immune genes in blood before and after cold exposure. We included both Dutch Europid and Dutch South Asian men to address whether the immune system is differently regulated in the metabolically vulnerable South Asian population. Methods Fasted blood samples were obtained from nonobese Dutch Europid (n = 11; mean age 26 ± 3 y) and Dutch South Asian (n = 12; mean age 28 ± 3 y) men before and directly after short-term (∼2.5 h) mild cold exposure. Transcript levels of 144 immune genes were measured using a dual-color reverse transcriptase multiplex ligation-dependent probe amplification (dcRT-MLPA) assay. Results Cold exposure acutely upregulated mRNA levels of GNLY (+35%, P < 0.001) and PRF1 (+45%, P < 0.001), which encode cytotoxic proteins, and CCL4 (+8%, P < 0.01) and CCL5 (+5%, P < 0.05), both pro-inflammatory chemokines. At thermoneutrality, mRNA levels of four markers of the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR)-family, involved in inflammasomes, were lower in Dutch South Asians compared to Dutch Europids, namely NLRP2 (−57%, P < 0.05), NLRP7 (−17%, P < 0.05), NLRP10 (−21%, P < 0.05), and NLRC4 (−23%, P < 0.05). Conclusions Mild cold exposure acutely increases mRNA levels of genes involved in cytotoxicity of immune cells in blood. In addition, Dutch South Asians display lower circulating mRNA levels of inflammasome genes compared to Dutch Europids.
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