Uric acid and glutathione levels during short-term whole body cold exposure

BCAA-nitrogen flux in brown fat controls metabolic health independent of thermogenesis

Brown adipose tissue (BAT) is best known for thermogenesis. Rodent studies demonstrated that enhanced BAT thermogenesis is tightly associated with increased energy expenditure, reduced body weight, and improved glucose homeostasis. However, human BAT is protective against type 2 diabetes, independent of body weight. The mechanism underlying this dissociation remains unclear. Here, we report that impaired mitochondrial catabolism of branched-chain amino acids (BCAAs) in BAT, by deleting mitochondrial BCAA carriers (MBCs), caused systemic insulin resistance without affecting energy expenditure and body weight. Brown adipocytes catabolized BCAA in the mitochondria as nitrogen donors for the biosynthesis of non-essential amino acids and glutathione. Impaired mitochondrial BCAA-nitrogen flux in BAT resulted in increased oxidative stress, decreased hepatic insulin signaling, and decreased circulating BCAA-derived metabolites. A high-fat diet attenuated BCAA-nitrogen flux and metabolite synthesis in BAT, whereas cold-activated BAT enhanced the synthesis. This work uncovers a metabolite-mediated pathway through which BAT controls metabolic health beyond thermogenesis.

The Influence of Whole-Body Cryotherapy or Winter Swimming on the Activity of Antioxidant Enzymes

The aim of this study was to investigate the effect of a series of 20 whole-body cryotherapy sessions and 20 winter swimming sessions on the level of catalase, glutathione peroxidase and superoxide dismutase. The experimental group consisted of 60 people (30 people received cryotherapy and 30 people swam in cold water). The control group-without intervention: 30 people. Each of the three groups was tested twice. Analyzing the changes in the examined indicators, a statistical increase of CAT was observed in men after the use of WBC, as well as an increase of SOD in women and a decrease of SOD in men after the winter swimming season. Regular WS does not seem to place an excessive burden on the body in terms of intensifying oxidative processes. WS sessions once a week can be recommended as an effective method of improving health by causing positive adaptive changes and strengthening the body's antioxidant barrier. WBC may be used as an adjunct therapy in the treatment of diseases caused by oxidative stress, as it improves the body's antioxidant capacity. Further research is needed to elucidate antioxidant mechanisms in humans and to determine the short- and long-term effects of exposure to WS and WBC.

Targeting Vascular Impairment, Neuroinflammation, and Oxidative Stress Dynamics with Whole-Body Cryotherapy in Multiple Sclerosis Treatment

Multiple sclerosis (MS), traditionally perceived as a neurodegenerative disease, exhibits significant vascular alternations, including blood-brain barrier (BBB) disruption, which may predispose patients to increased cardiovascular risks. This vascular dysfunction is intricately linked with the infiltration of immune cells into the central nervous system (CNS), which plays a significant role in perpetuating neuroinflammation. Additionally, oxidative stress serves not only as a byproduct of inflammatory processes but also as an active contributor to neural damage. The synthesis of these multifaceted aspects highlights the importance of understanding their cumulative impact on MS progression. This review reveals that the triad of vascular damage, chronic inflammation, and oxidative imbalance may be considered interdependent processes that exacerbate each other, underscoring the need for holistic and multi-targeted therapeutic approaches in MS management. There is a necessity for reevaluating MS treatment strategies to encompass these overlapping pathologies, offering insights for future research and potential therapeutic interventions. Whole-body cryotherapy (WBCT) emerges as one of the potential avenues for holistic MS management approaches which may alleviate the triad of MS progression factors in multiple ways.

Impact of cold exposure on life satisfaction and physical composition of soldiers

This article has been retracted.

Exercise in cold: Friend than foe to cardiovascular health

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.

The Influence of Winter Swimming on Oxidative Stress Indicators in the Blood of Healthy Males

Baths in cold water are a popular physical activity performed to improve health. This study aimed to determine whether repeated cold-water exposure leads to the up-regulation of antioxidant defenses and whether or not this leads to a reduction in basal and/or acute pulses of oxidative distress in humans. The study group consisted of 28 healthy male members of the WS club (average age 39.3 ± 6.1 years). The study sessions occurred at the beginning and the end of the WS season. During the WS season, the participants took 3-min cold-water baths in a cold lake once a week. Blood samples were collected three times during each session: before the bath, 30 min after the bath, and 24 h after the bath. The activity of selected antioxidant enzymes, including superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPx), as well as the concentration of lipid peroxidation (LPO) products, including thiobarbituric acid-reactive substances (TBARS) and conjugated dienes (CD), were determined in erythrocytes. The concentration of TBARS, CD, retinol, and α-tocopherol were determined in the blood plasma, whereas the level of other LPO products, including 4-hydroxynonenal and 8-iso-prostaglandin F2α, were determined in the blood serum. The repeated cold exposure up-regulated most antioxidant defenses, and this led to an attenuation of most indicators of oxidative stress at the baseline and acute pulses in response to cold exposure. In conclusion, due to regular cold exposure, the antioxidant barrier of winter swimmers was stimulated. Thus, short cold-bath sessions seem to be an effective intervention, inducing promoting positive adaptive changes such as the increased antioxidant capacity of the organism.

Health effects of voluntary exposure to cold water - a continuing subject of debate

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.

Correlating multi-functional role of cold shock domain proteins with intrinsically disordered regions

Cold shock proteins (CSPs) are an ancient and conserved family of proteins. They are renowned for their role in response to low-temperature stress in bacteria and nucleic acid binding activities. In prokaryotes, cold and non-cold inducible CSPs are involved in various cellular and metabolic processes such as growth and development, osmotic oxidation, starvation, stress tolerance, and host cell invasion. In prokaryotes, cold shock condition reduces cell transcription and translation efficiency. Eukaryotic cold shock domain (CSD) proteins are evolved form of prokaryotic CSPs where CSD is flanked by N- and C-terminal domains. Eukaryotic CSPs are multi-functional proteins. CSPs also act as nucleic acid chaperons by preventing the formation of secondary structures in mRNA at low temperatures. In human, CSD proteins play a crucial role in the progression of breast cancer, colon cancer, lung cancer, and Alzheimer's disease. A well-defined three-dimensional structure of intrinsically disordered regions of CSPs family members is still undetermined. In this article, intrinsic disorder regions of CSPs have been explored systematically to understand the pleiotropic role of the cold shock family of proteins.

Are the levels of uric acid associated with biometeorological conditions?

Hyperuricemia is an independent risk factor for renal and cardiovascular diseases and is closely associated with gout episodes. It is caused, inter alia, by nutritional habits and genetic factors, and also displays seasonal variability conditioned by meteorological factors. The impact of meteorological factors, including both cold and heat stress, on the human physiology is presented based on the Universal Thermal Climate Index (UTCI) - a biometeorological index derived from an analysis of human thermal balance. The aim of our study was to establish whether seasonal variations significantly affect routinely measured urine acid (UA) levels and could eventually support the clinical decision making process, as well as assessing whether UTCI values are correlated with UA levels in blood serum. This work presents a retrospective epidemiological study of data collected in Olsztyn (Poland). Study material comprised 54,536 results of ambulatory tests measuring UA levels, performed during the period 2016-2019. The analysis concerned correlations between UA and the ages of female and male subjects as well as existing biometeorological conditions as represented by UTCI values in an annual cycle. UA levels in females were found to be lower (4.94 ± 1.37 SD) as compared to those of males (6.13 ± 1.43 SD) and demonstrated a strong positive correlation with age. UA values differed significantly (p < 0.05) on days characterized by cold stress and heat stress, for the oldest age group. UA levels were found to differ depending on the season, but these relationships were not statistically significant, except for significantly higher UA levels in females in autumn (p < 0.001). However, there was an evident difference in population UA levels under cold stress conditions (lower) and heat stress conditions (higher) in the elderly. The UTCI is an adequate predictor of population variations in UA levels since it takes into account the variability of local meteorological conditions.

Cold Water Swimming-Benefits and Risks: A Narrative Review

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.

Assessment of blood morphology, electrolyte level as well as kidney and liver function before and after leaving the water in a winter swimmers during the entire winter swimming season - a case study

Study aim: The aim of the study was to assess blood morphology, electrolyte level as well as indices of kidney function and the activity of selected liver enzymes determining liver function before and after exiting the water in a winter swimmer (“Walrus”) from the “Kaloryfer” (“Radiator”) Krakow Winter Swimming Club during the whole winter bathing season. Materials and methods: The subject of research was a winter swimmer from the “Radiator” Krakow Winter Swimming Club  a 53-year-old male. Blood was collected from the subject: at the beginning of the winter swimming season, during (five times) and at the end of the season (each time before and after getting out of the water); time maintaining in water: 10 minutes. Results: Analysing the average values of the indices before and after exiting the water, statistically significant increases were noted in AST [U/L] by 6.4% and LDH [U/L] by 2.45%, as well as a decrease in Na+ [mmol/l] by 1.14%, Clˉ [mmol/l] by 1.78% and urea [mmol/l] by 3.64%. Conclusions: Regular baths taken by the winter swimmers in cold water did not affect blood morphology indices and did not cause pathological changes in kidney profile. Furthermore, slight fluctuations regarding the concentration of electrolytes in the blood serum and changes in the hepatic profile additionally “externalised” health problems, which appeared prior to winter swimming.

The Influence of Post-Exercise Cold-Water Immersion on Adaptive Responses to Exercise: A Review of the Literature

Post-exercise cold-water immersion (CWI) is used extensively in exercise training as a means to minimise fatigue and expedite recovery between sessions. However, debate exists around its merit in long-term training regimens. While an improvement in recovery following a single session of exercise may improve subsequent training quality and stimulus, reports have emerged suggesting CWI may attenuate long-term adaptations to exercise training. Recent developments in the understanding of the molecular mechanisms governing the adaptive response to exercise in human skeletal muscle have provided potential mechanistic insight into the effects of CWI on training adaptations. Preliminary evidence suggests that CWI may blunt resistance signalling pathways following a single exercise session, as well as attenuate key long-term resistance training adaptations such as strength and muscle mass. Conversely, CWI may augment endurance signalling pathways and the expression of genes key to mitochondrial biogenesis following a single endurance exercise session, but have little to no effect on the content of proteins key to mitochondrial biogenesis following long-term endurance training. This review explores current evidence regarding the underlying molecular mechanisms by which CWI may alter cellular signalling and the long-term adaptive response to exercise in human skeletal muscle.

Effect of Whole-Body Cryotherapy on Antioxidant Systems in Experimental Rat Model

Background

The purpose of this study was to verify the effect of whole-body cryotherapy (WBC) in rats on their antioxidant systems, lipid peroxidation products, and their total oxidative status at different exposure times and temperatures.

Methods

Antioxidants in serum, plasma, liver, and erythrocytes were evaluated in two study groups following 1 min of exposure to −60°C and −90°C, for 5 and 10 consecutive days.

Results

WBC increased the activity of superoxide dismutase, catalase in the group subjected to 5 and 10 days exposure, −60°C. The glutathione S-transferase activity increased in the groups subjected to 10 days WBC sessions. Total antioxidant capacity increased after 5 and 10 days of 1 min WBC, −60°C; a decrease was observed at −90°C. A decreased level of erythrocyte malondialdehyde concentration was observed at −60°C after 5 and 10 days of cryostimulation. An increased concentration was measured at −90°C after 10 days, and increase of erythrocyte malondialdehyde concentration after 5 days, −90°C.

Conclusions

To the best of our knowledge, this is the first research showing the effect of WBC in rats at different exposure times and temperatures. The effect of cryotherapy on enzymatic and nonenzymatic antioxidant systems was observed in the serum of animals exposed to a temperature of −60°C in comparison to control.

Single and combined effects of zinc and cinnamon essential oil in diet on productive performance, egg quality traits, and blood parameters of laying hens reared under cold stress condition

This study was conducted to evaluate the effects of adding zinc (Zn), cinnamon essential oil (Ci), or their combination in diet on productive performance, egg quality, and blood parameters of laying hens reared under cold stress condition (8.8 ± 3 °C). Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 56-day trial period using 120 Lohmann LSL-Lite laying hens. Significant interactions between Ci and Zn on FCR, EW, EP, or EM were observed (P < 0.05). The EP, EM, and EW increased, whereas FCR decreased (P < 0.05) in the hens fed the diets including Ci and Zn (as single or combined form) compared to those fed the basal diet. There were significant interactions between Ci and Zn on the serum level of glucose and triglycerides as well as plasma concentration of zinc (P < 0.05), so that serum content of glucose and triglyceride decreased and the plasma content of zinc increased in the hens fed the diets including Ci and Zn (together) compared to those fed the basal diet. From the results of the present experiment, it can be concluded that diet supplementation by the combined form of Ci and Zn could have beneficial effects on performance and blood parameters of hens reared under cold stress condition.

Postexercise impact of ice-cold water bath on the oxidant-antioxidant balance in healthy men

The aim of the study was to determine the effect of a 5 min head-out ice-cold water bath on the oxidant-antioxidant balance in response to exercise. The crossover study included the subjects (n = 24; aged 28.7 ± 7.3 years) who performed two identical stationary cycling bouts for 30 min and recovered for 10 min at room temperature (RT = 20°C; session 1) or in a pool with ice-cold water (ICW = 3°C, 5 min immersion; session 2). The concentration of thiobarbituric acid reactive substances (TBARS) in blood plasma (TBARSpl) and erythrocytes (TBARSer) and the erythrocytic activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were measured three times during each of the two study sessions: before the exercise (baseline) and 20 and 40 min after the appropriate recovery session. Lower concentration of TBARSpl 40 min after postexercise recovery in ICW was revealed as compared with that after recovery at RT (P < 0.05). Moreover, a statistically significant postexercise increase in the TBARSpl and TBARSer concentrations was found (P < 0.01 and P < 0.05, resp.). A short-term ice-cold water bath decreases postexercise lipid peroxidation.

The influence of obesity and ambient temperature on physiological and oxidative responses to submaximal exercise

This study investigated the effects of obesity and ambient temperature on physiological responses and markers of oxidative stress to submaximal exercise in obese and lean people. Sixteen healthy males were divided into an obese group (n=8, %fat: 27.00±3.00%) and a lean group (n=8, %fat: 13.85±2.45%). Study variables were measured during a 60 min submaximal exercise test at 60% VO2max in a neutral (21±1°C) and a cold (4±1°C) environment. Heart rate, blood lactate, rectal temperature, serum levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were measured at rest, during exercise and in recovery. Heart rate of both groups was significantly lower (P<0.05) in the cold than the warm environment, but there were no significant differences between the two groups. Serum SOD activity increased to a significantly greater extent (P<0.05) in the cold than the neutral environment, and remained elevated for longer during exercise in the obese group than the lean group. Serum MDA level during submaximal exercise was not significantly different between conditions or groups. Cold stress in exercise may challenge antioxidant defence mechanisms in obese subjects, but lipid peroxidation remains unchanged.

Influence of inflammatory pathway markers on oxidative stress induced by cold stress in intestine of quails

The cold temperature reduces the immunity and re-production activities of the poultry. This study aimed to investigate the effects of acute and chronic cold exposure on the regulation of nuclear factor-kappa B (NF-κB) and tumor necrosis factor-α (TNF-α) expression in the duodenum, jejunum, and ileum of quails. In this study, 96 15-d-old male quails were randomly allocated into 12 groups (eight each group) for exposure to acute (up to 12h) and chronic (up to 20 days) cold stress (12 ± 1°C). Antioxidative function was examined by superoxide dismutase (SOD) and oxidative damage was examined by malondialdehyde (MDA) detection. qRT-PCR was performed to analyze expression of NF-κB and TNF-α, and DNA sequencing was performed to analyze PCR products. The data showed that under cold stress, the SOD level decreased, and the MDA level had the tendency to increase in duodenum, jejunum and ileum of quails, while the mRNA expression of NF-κB increased and TNF-α decreased in duodenum, jejunum and ileum of quails. The data from the current study indicated that both acute and chronic cold stresses were able to induce inflammatory responses in the duodenum, jejunum and ileum, which might be due to the cold-damaged intestinal oxidative stress.

Winter-swimming as a building-up body resistance factor inducing adaptive changes in the oxidant/antioxidant status

The aim of our research was to examine whether winter-swimming for five consecutive months results in adaptational changes improving tolerance to stress induced by exposure to cryogenic temperatures during whole-body cryostimulation (WBC). The research involved 15 healthy men, with normal bodyweight, who had never been subjected to either WBC or cold water immersion. During the experiment, the participants were twice subjected to WBC (3 min/- 130°C), namely before the winter-swimming season and after the season. Blood was taken seven times: In the morning before each cryostimulation, 30 min after each cryostimulation and the next morning. Additionally, control blood was collected in the middle of the winter season, in February. Our analysis concerned changes in hematological parameters as well as in reduced glutathione and oxidized glutathione, total oxidant status, total antioxidant status and in components of the antioxidant system: Superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase and 8-Isoprostanes as a sensitive indicator of oxidative stress. We found significant changes in hemoglobin concentration, the number of red blood cells, the hematocrit index and mean corpuscular volume of red blood cell and the percentage of monocytes and granulocytes after the winter swimming season. The response to cryogenic temperatures was milder after five months of winter-swimming. The obtained results may indicate positive adaptive changes in the antioxidant system of healthy winter-swimmers. These changes seem to increase the readiness of the human body to stress factors.

Whole-body cryostimulation--potential beneficial treatment for improving antioxidant capacity in healthy men--significance of the number of sessions

It is claimed that WBC (whole-body cryotherapy) enhances the resistance of the human body, also thanks to the beneficial effect on the antioxidant system. Accordingly, this research aimed to evaluate the effect of a series of whole-body cryostimulations on the level of non-enzymatic antioxidants and the activity of antioxidant enzymes in healthy men. The study was carried out on 30 young and healthy men aged 27.8±6.1 years with average body mass index and peak oxygen consumption (46.34±6.15 ml kg(-1) •min(-1)). The participants were daily exposed for 3 minutes to cryogenic temperatures (-130°C). Blood samples were obtained in the morning before cryostimulation, again 30 min after exposure and the following day in the morning, during the 1(st), 10(th) and 20(th) session. Analysis concerned changes in plasma concentrations of total protein, albumin, glucose, uric acid and ceruloplasmin, and the most important components of the antioxidant system in red blood cells: superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, reduced and oxidized glutathione. To assess the oxidative stress level the 8-isoprostane concentration in plasma was measured. The obtained results indicate that cryogenic temperatures in repeated daily treatments result in changes in the peroxidant and antioxidant status. These changes seem to depend on the number of cryostimulations. After 20 daily treatments there was an increase in SOD, SOD:CAT ratio, a decrease in the concentration of reduced and oxidized glutathione and in the activity of GPx. It could be possible that differences in the activity of GSSG-R after 20 treatments depended on the body mass index of participants.

The effect of prolonged whole-body cryostimulation treatment with different amounts of sessions on chosen pro- and anti-inflammatory cytokines levels in healthy men

Cryotherapy is used in the early treatment of acute injuries (sprains, strains, fractures) yet only a few papers discuss the possible influence of whole-body cryostimulation on inflammation mechanisms or immunology. It is postulated that cold exposure can have an immunostimulating effect related to enhanced noradrenaline response and can be connected with paracrine effects. The aim of this study was to examine the effect of different sequences of whole-body cryostimulations on the level of pro- and anti-inflammatory cytokines in healthy individuals. The research involved 45 healthy men divided into three groups. The groups were subjected to 5, 10 or 20, 3-minute long whole-body cryostimulations each day at -130°C. Blood was collected for analysis before the stimulations, after completion of the whole series, and 2 weeks after completion of the series, for the examination of any long-term effect. The analysis of results showed that in response to cryostimulation, the level of ani-inflammatory cytokines IL-6 and IL-10 increased while Il-1α cytokine level decreased. It seems that the most advantageous sequence was the series of 20 cryostimulations due to the longest lasting effects of stimulation after the completion of the whole series of treatments.

Effects of whole-body cryotherapy on a total antioxidative status and activities of antioxidative enzymes in blood of depressive multiple sclerosis patients

OBJECTIVES

Oxidative stress (OS) plays an important role in the pathogenesis of multiple sclerosis (MS). In MS patients depression is often observed. Cryotherapy might have an effect on OS. The aim of this study was to compare the effects of whole body cryotherapy (WBCT) on changes in total antioxidative status (TAS) of plasma and activities of antioxidative enzymes in erythrocytes from depressive and non depressive MS patients.

METHODS

Twenty-two MS patients with secondary progressive disease course (12 depressive and 10 non depressive) were treated with 10 exposures in a cryochamber. Before and after WBCT the plasma TAS and the activities of superoxide dismutase (SOD) and catalase (CAT) in the erythrocytes were measured.

RESULTS

The level of TAS in depressive MS group was significantly lower than in non depressive MS (P < 0.0003). WBCT increased the level of TAS in depressive (P < 0.002) more than in non depressive MS patients (P < 0.01). WBCT treatment of MS patients resulted in the significant increase of TAS level in plasma but had no effects on activities of SOD and CAT.

CONCLUSIONS

Our results indicate that WBCT suppresses OS in MS patients, especially in depressive patients.

Whole-body cryotherapy in athletes

Cold therapy is commonly used as a procedure to relieve pain symptoms, particularly in inflammatory diseases, injuries and overuse symptoms. A peculiar form of cold therapy (or stimulation) was proposed 30 years ago for the treatment of rheumatic diseases. The therapy, called whole-body cryotherapy (WBC), consists of exposure to very cold air that is maintained at -110 degrees C to -140 degrees C in special temperature-controlled cryochambers, generally for 2 minutes. WBC is used to relieve pain and inflammatory symptoms caused by numerous disorders, particularly those associated with rheumatic conditions, and is recommended for the treatment of arthritis, fibromyalgia and ankylosing spondylitis. In sports medicine, WBC has gained wider acceptance as a method to improve recovery from muscle injury. Unfortunately, there are few papers concerning the application of the treatment on athletes. The study of possible enhancement of recovery from injuries and possible modification of physiological parameters, taking into consideration the limits imposed by antidoping rules, is crucial for athletes and sports physicians for judging the real benefits and/or limits of WBC. According to the available literature, WBC is not harmful or detrimental in healthy subjects. The treatment does not enhance bone marrow production and could reduce the sport-induced haemolysis. WBC induces oxidative stress, but at a low level. Repeated treatments are apparently not able to induce cumulative effects; on the contrary, adaptive changes on antioxidant status are elicited--the adaptation is evident where WBC precedes or accompanies intense training. WBC is not characterized by modifications of immunological markers and leukocytes, and it seems to not be harmful to the immunological system. The WBC effect is probably linked to the modifications of immunological molecules having paracrine effects, and not to systemic immunological functions. In fact, there is an increase in anti-inflammatory cytokine interleukin (IL)-10, and a decrease in proinflammatory cytokine IL-2 and chemokine IL-8. Moreover, the decrease in intercellular adhesion molecule-1 supported the anti-inflammatory response. Lysosomal membranes are stabilized by WBC, reducing potential negative effects on proteins of lysosomal enzymes. The cold stimulation shows positive effects on the muscular enzymes creatine kinase and lactate dehydrogenase, and it should be considered a procedure that facilitates athletes' recovery. Cardiac markers troponin I and high-sensitivity C-reactive protein, parameters linked to damage and necrosis of cardiac muscular tissue, but also to tissue repair, were unchanged, demonstrating that there was no damage, even minimal, in the heart during the treatment. N-Terminal pro B-type natriuretic peptide (NT-proBNP), a parameter linked to heart failure and ventricular power decrease, showed an increase, due to cold stress. However, the NT-proBNP concentrations observed after WBC were lower than those measured after a heavy training session, suggesting that the treatment limits the increase of the parameter that is typical of physical exercise. WBC did not stimulate the pituitary-adrenal cortex axis: the hormonal modifications are linked mainly to the body's adaptation to the stress, shown by an increase of noradrenaline (norepinephrine). We conclude that WBC is not harmful and does not induce general or specific negative effects in athletes. The treatment does not induce modifications of biochemical and haematological parameters, which could be suspected in athletes who may be cheating. The published data are generally not controversial, but further studies are necessary to confirm the present observations.

Effects of the whole-body cryotherapy on a total antioxidative status and activities of some antioxidative enzymes in blood of patients with multiple sclerosis-preliminary study

OBJECTIVE

There is evidence that multiple sclerosis (MS) is not only characterized by immune mediated inflammatory reactions but also by neurodegenerative processes. Neutralization of oxidative stress and excitotoxicity, might represent a therapeutic approach to provide neuroprotection in MS. The purpose of this study was to compare changes in total antioxidative status and activities of chosen antioxidative enzymes, such as: SOD, CAT in erythrocytes of patients with MS before and after using WBCT with control group.

MATERIALS AND METHODS

32 patients with multiple sclerosis (ICD10-G35) and 20 healthy subjects were recruited for the study. The examined MS group (n=16) was treated with a series of 10 daily exposures in a cryogenic chamber (2-3 min, from -120 degrees C to -110 degrees C) and program of exercises. The control MS group (n=16) had only exercises. Plasma TAS as well as SOD and CAT activities in erythrocytes were measured.

RESULTS

The level of TAS in MS patients was distinctly reduced compared to healthy subjects. After two weeks of WBCT treatment an increase of TAS in the whole examined group (p>0.01) were observed in relation to control MS group. There was not increase of CuZnSOD and CAT activities.

CONCLUSION

Our results suggest positive antioxidant effects of WBCT as a short-term adjuvant treatment for patients suffered due to MS.

Biomarkers of protein oxidation from a chemical, biological and medical point of view

In physiological conditions intracellular radical formation is mostly due to mitochondrial activity. This is in contrast to clinical and pathophysiological situations, where the oxidant formation is additionally driven by xenobiotics and inflammation. Oxidative damage accumulation in macromolecules especially in proteins has been considered as a cause of cellular damage and pathology impairing the clinical outcome of patients. However, up to now strategies to measure oxidative stress in clinical settings are limited. A lot of parameters and techniques are available for the determination of oxidized proteins in biological systems. Unfortunately, most of them are no reliable markers in clinical settings due to their unknown clinical relevance or the lack in clinical feasibility. Major problems are the sample availability, sample stability and cost-, time- and man-power intensive methods. The present review focuses on the measurement of protein oxidation products from a chemical, biological, and medical point of view.

Do sessions of cryostimulation have influence on white blood cell count, level of IL6 and total oxidative and antioxidative status in healthy men?

The influence of extremely low temperatures on the human body and physiological reactions are not fully recognized. It has been postulated that cryostimulation could modify immunological reactions, leukocytes mobilization and levels of cytokines. The aim of this research was to estimate the influence of a ten sessions 3-min-long exposures to cryogenic temperature (-130 degrees C) on the white blood cell (WBC) count, level of IL6 and the total oxidative and antioxidative status in 15 young, clinically healthy men. Blood samples were obtained in the morning before cryostimulation, again 30 min after treatment and the next day in the morning, both during the first and tenth session. The WBC count, level of IL6 and total lipid peroxides as the total oxidative status and the total antioxidative status (TAS), were measured. After completing a total of ten whole-body therapy sessions a significant increase in WBC count, especially lymphocytes and monocytes was noted. There was an increase in level of IL6 after first and the last cryostimulation the most pronounced after tenth session. On the contrary the TAS level decreased significant after the treatment. It was concluded that repeated expositions to extremely low temperatures use in cryostimulation have mobilization effect on immunological system.

Effect of melatonin on burn-induced gastric mucosal injury in rats

We studied the effect of melatonin treatment on gastric mucosal damage induced by experimental burns and its possible relation to changes in gastric lipid peroxidation status. Melatonin was intraperitoneally applied immediately after third-degree burns over 30% of total body skin surface area of rats. Malondialdehyde (MDA), uric acid (UA) and sulphydril (SH) levels were determined in gastric mucosa and blood plasma and used as biomarkers of the oxidative stress. The results showed that the skin burn caused oxidative stress evidenced by accumulation of MDA and UA as well as the depletion of SHs in gastric mucosa. Plasma MDA concentrations were elevated, while plasma SH concentrations were decreased after burns. Melatonin (10 mg per kg body weight) protected gastric mucosa from oxidative damage by suppressing lipid peroxidation and activating the antioxidant defence. It may be hypothesised that melatonin restores the redox balance in the gastric mucosa and protects it from burn-induced oxidative injury. Melatonin has no significant influence on the concentrations of plasma MDA and antioxidants after burn; therefore, it should largely be considered as a limiting factor for tissue-damage.

Activity of selected enzymes in erythrocytes and level of plasma antioxidants in response to single whole-body cryostimulation in humans

The influence of extremely low temperatures on the human body and physiological reactions is not fully understood. The aim of this research was to estimate the influence of a single exposure to cryogenic temperature (-130 degrees C), without subsequent kinesiotherapy, on the activity of the most crucial antioxidant enzymes in erythrocytes: superoxide dismutase (SOD), catalase (CAT), glutathione reductase (R-GSSG), glutathione peroxidase (GPx) and glutathione transferase (T-GSH). In the plasma, the concentrations of glutathione, uric acid, albumins and extra-erythrocyte haemoglobin as components of the non-enzymatic antioxidant system were evaluated. The subjects were 10 healthy young men. Blood was sampled in the morning on the day of cryostimulation, 30 min after cryostimulation and the next morning. The enzymatic response of the antioxidant defence to the influence of the extremely low temperature resulted in an immediate, significant, increase in GPx and R-GSSG activities, but a decrease in CAT and T-GSH activities. We observed an increase in the concentrations of all the examined non-enzymatic antioxidants, especially extra-erythrocyte haemoglobin and uric acid, which had both increased further the day after cryostimulation. The results indicate that a single stimulation with cryogenic temperatures results in oxidative stress in a healthy body, but that the level of stress is not very high. It seems that in this case the most significant role in the antioxidant mechanisms is played by peroxidase.

Coronary blood flow after cold exposure and the effect of warm-up exercise

BACKGROUND

Cold pressor test (CPT) results indicate that coronary blood flow (CBF) increases after sudden cold exposure. Traditionally, warm-up exercise (WEx) has been recommended before cold exposure; however, the physiologic effects of WEx on CBF have not been elucidated. Therefore, this study was undertaken to evaluate the effect of WEx on CBF after cold exposure.

METHODS

Fifteen healthy young men were enrolled in this study. CBF at the distal left anterior descending coronary artery was assessed by transthoracic Doppler echocardiography at baseline and after CPT. The same measurements were made with WEx and weight-bearing exercise before CPT after a 20-minute recovery period between each measurement. In the CBF velocities, the time-velocity integral of diastolic flow (Dtvi) was measured in addition to blood pressure and heart rate (HR).

RESULTS

The product of Dtvi x HR increased significantly after CPT. Increments in Dtvi x HR after CPT with WEx before CPT were significantly higher than CPT alone (130 +/- 82% vs 68 +/- 37%, P < .05). However, increments in Dtvi x HR after CPT with weight-bearing exercise before CPT were not significantly different from those observed for CPT alone (74 +/- 50% vs 68 +/- 37%, P = not significant).

CONCLUSION

Our study suggests that WEx can augment an increased CBF after cold exposure. This augmentation of CBF increase after cold exposure may help the body meet increased physiologic demands imposed on it by cold exposure. However, this phenomenon was not observed for anaerobic weight-bearing exercise.

Acute and long-term effects of winter swimming and whole-body cryotherapy on plasma antioxidative capacity in healthy women

The effects of severe cold stress on total peroxyl radical trapping antioxidant capacity of plasma (TRAP) were studied in two groups of healthy women: a whole-body cryotherapy group (WBC, n = 10) and a winter swimming group (WS, n = 10). The biovariability of TRAP values was also analysed. The WBC group was exposed to -110 degrees C for 2 min, whereas the exposure for the WS group lasted 20 s in ice-cold water. Sessions were organized three times per week for 12 weeks. Blood specimens were collected at 2, 4, 8 and 12 weeks at rest, 2 and 35 min after the cold exposures and at the corresponding times without cold exposure on a separate day. Conventional methods were used to determine TRAP values. The between-subject variation was 13.6% and the within-subject variation 6.4%. The index of individuality was 0.46, and the index of heterogeneity was 0.079. These results indicate a marked heterogeneity among subjects. During the first 4 weeks, the mean TRAP value significantly increased at 2 min after cold exposure in the WBC group, returning to baseline 35 min after the exposure. Similar changes were observed in the WS group. However, all changes due to cold were relatively mild (<5%). After 4 weeks no changes in TRAP values after the cold exposures were noticed and no long-term changes in basal TRAP values were observed. In the main, regular WBC and WS do not seem to be harmful as far as plasma antioxidative capacity is concerned.

The Impact of Prolonged Exercise in a Cold Environment upon Cardiac Function

PURPOSE

The purpose of the present study was to examine the impact of cold exposure coupled with prolonged exercise upon postexercise left ventricular (LV) function and markers of myocardial damage.

METHODS

colon; Eight highly trained male athletes (mean +/- SD; age: 28.2 +/- 8.8 yr; height: 1.78 +/- 0.07 m; body mass: 74.9 +/- 7.6 kg; VO2max: 65.6 +/- 7.0 mL x kg(-1) x min(-1)) performed two 100-mile cycle trials, the first in an ambient temperature of 0 degrees C, the second in an ambient temperature of 19 degrees C. Echocardiographic assessment was completed and blood samples drawn before, immediately postexercise, and 24-h postexercise. Left ventricular systolic (stroke volume [SV], ejection fraction [EF], and systolic blood pressure/end systolic volume ratio [SBP/ESV]) and diastolic (early [E] to late [A] filling ratio [E:A]) parameters were calculated. Serum was analyzed for creatine kinase isoenzyme MB (CK-MBmass) and cardiac troponin T (cTnT). cTnT was analyzed descriptively whereas other variables were assessed using two-way repeated-measures ANOVA.

RESULTS

No significant change was observed in systolic function across time or between trials. A significant difference between trials was observed in E:A immediately after exercise (1.4 +/- 0.4 [19 degrees C] vs 1.8 +/- 0.3 [0 degrees C]) (P < 0.05). CK-MBmass was significantly elevated immediately after exercise in both trials (P < 0.05). Positive cTnT concentrations were observed in two subjects immediately after the 19 degrees C trial (0.012 microg x L(-1) and 0.034 microg x L(-1)).

CONCLUSIONS

Cycling 100 miles in an ambient temperature of 19 degrees C is associated with an acute change in diastolic filling that is not observed after prolonged exercise at 0 degrees C. Prolonged exercise is associated with minimal cardiac damage in some individuals; it appears that this is a separate phenomenon to the change in diastolic filling.

Winter swimming: healthy or hazardous? Evidence and hypotheses

Swimming in cold water during the winter season is an extreme sport, with fans all over the world. However, its effects on health have been debated. This article examines the hypothesis that the effects of winter swimming may depend on previous exposure to cold stimuli. Immersion in cold water in unaccustomed persons may lead to detrimental consequences, while, in regular winter swimmers, adaptive physiologic mechanisms increase tolerance to cold. Furthermore, these mechanisms may prevent the occurrence of a wide variety of diseases. Prospective studies and epidemiological data are needed to test this hypothesis.

Neurotic psychopathology and alexithymia among winter swimmers and controls--a prospective study

Random samples of 25 voluntary Finnish winter swimmers (7 males, 18 females) and 11 controls (3 males, 8 females were followed prospectively during the winter season from October 1999 to May 2000 to (determine whether winter swimming is beneficial for mental well-being, as many of its practitioners claim. The Crown-Crisp Experimental Index (CCEI) was used for measuring free-floating anxiety, phobic anxiety, obsessionality, depression, somatic anxiety and hysteria, and the 20-item version of the Toronto Alexithymia Scale (TAS-20) for measuring alexithymia. Self-reported somatic and mental health and the reasons for and the frequency of winter-swimming were asked, too. As resealed by open questions, the winter swimmers reported positive effects of winter swimming. Several of the swimmers also told that they had started winter swimming to improve their physical and mental health. Their experience was that the swimming had relieved physical symptoms and made their mood more positive. However, we found no major differences between winter swimmers and controls in any CCEI or TAS variables. The structured questionnaires do not necessarily, however, reach subjective feelings and experiences.

Blood Glutathione Disulfide: In Vivo Factor or in Vitro Artifact?

Background: The reported mean concentration of glutathione disulfide (GSSG) in human blood/erythrocytes varies widely (1 to &gt;500 μmol/L), as does that of reduced glutathione (GSH) to a lesser extent. We have identified and investigated possible pitfalls in measurement of both GSH and GSSG.

Methods: We measured GSH and GSSG using a spectrophotometer with a modification of the GSH recycling method; the same samples were also measured by reversed-phase HPLC after derivatization of thiols (dithiothreitol was used to reduce disulfides) with monobromobimane. The thiol-bimane adduct was measured by a fluorescence detector.

Results: Measured GSH/GSSG concentrations were affected by the following: (a) oxidation of thiols in acidified samples; (b) oxidation after restoring neutral-alkaline pH; (c) oxidation during acid deproteinization; (d) shift in the GSH/GSSG equilibrium because of irreversible blocking of free thiols; and (e) reaction of electrophiles with amino groups. In particular, oxidation during sample deproteinization with acid influenced and produced artifacts (30–150 μmol/L GSSG was produced by this procedure); this phenomenon was directly correlated with the presence of oxygenated hemoglobin, being minimized by both oxygen deprivation and incubation in an atmosphere of 5% carbon monoxide.

Conclusions: GSSG is present in healthy human blood at low concentrations (2–6 μmol/L), and most published data on GSSG may be affected by artifacts.

Urinary and plasma purine derivatives in fed and fasted llamas (Lama glama and L. guanacoe)

The changes in urinary and plasma purine derivatives in response to fasting and level of feeding in llamas were examines. In one experiment, four llamas were gradually deprived of feed within 3 days and then fasted for 6 days. Daily urinary excretion of purine derivatives decreased with feed intake and leveled on the last 3 days of fasting at 177 +/- 26 mumol/kg W0.75. Allantoin and uric acid comprised 71% and 15% of total purine derivatives, respectively, in both fed and fasted states, but hypoxanthine plus xanthine increased from 9% to 36%. Plasma concentration of allantoin declined with feed intake reduction, but those of uric acid (217 mumol/l) and hypoxanthine plus xanthine (27 mumol/l) remained relatively unchanged. Concentration of uric acid was higher than that of allantoin, probably due to a high reabsorption of uric acid in renal tubules, which was measured as over 90%. In a second experiment, the four llamas were fed at 860 and 1740 g dry matter/d in a crossover design. Urinary total purine derivatives excretion responded to feed intake (10.4 vs 14.4 mmol/d), although the observed differences did not reach significance. Compared with some ruminant species, it appears that the llama resembles sheep regarding the magnitude of urinary purine derivatives excretion but is unique in maintaining a high concentration of uric acid in plasma, which could be part of the llama's adaptation to their environment.

Bi-enzyme reactor for electrochemical detection of low concentrations of uric acid and glucose

An enzyme-based flow-injection amperometric analysis system (FIA) for monitoring of uric acid and glucose is described. The oxidase and peroxidase enzymes are physically coimmobilised in a sandwich-type reactor and ferrocene serves as a mediator. The assays are based on the measurement of a reduction current resulting from the enzymatic reactions, at a glassy carbon electrode held at 0.00 mV (vs. Ag/AgCl). The high selectivity (ascorbic acid did not interfere) is coupled to high sensitivity (a detection limit of 30 and 60 nmol/l for uric acid and glucose, respectively; signal/noise = 3) and good stability (the enzymes remained active for more than 6 weeks at 30 degrees C). The usefulness of the assay in clinical chemistry is illustrated by the measurement of human serum uric acid and glucose concentration. The results obtained were in fairly good agreement with those obtained using conventional hospital laboratory methods.

Concentration of purine compounds in the cerebrospinal fluid of infants suffering from sepsis, convulsions and hydrocephalus

Catabolites of purine nucleotides were measured in the cerebrospinal fluid (CSF) of newborn infants with sepsis, seizures and hydrocephalus using isocratic reversed-phase HPLC. The inosine levels in the CSF of the infants with any of the illnesses were significantly higher when compared with the controls. There was a tendency for hypoxanthine levels to be higher in the group of children with hydrocephalus. No significant differences in the concentrations of xanthine, adenine and uric acid were found. The inosine concentration in the CSF is proposed to be a more sensitive indicator of brain injury than the levels of other CSF purines. The levels of all purine metabolites measured in the CSF showed large individual variations. The ratio between hypoxanthine (as an indicator of ATP breakdown) and uric acid (as a scavenger of oxygen free radicals) concentration is proposed as a new criterion to be used in the evaluation of brain injury.