Human resting extracellular heat shock protein 72 concentration decreases during the initial adaptation to exercise in a hot, humid environment.
ABSTRACT Heat shock protein (Hsp) 72 is a cytosolic protein that also is present in the circulation. Extracellular Hsp72 (eHsp72) is inducible by exercise and is suggested to act as a danger signal to the immune system. The adaptive response of eHsp72 to repeated exercise-heat exposures in humans remains to be determined. An intracellular animal study found a reduced Hsp72 response, with no change in resting levels, during heat stress after a single day of passive heat acclimation. The current study therefore tested whether adaptations in human eHsp72 levels would similarly occur 24 hours after a single exercise-heat exposure. Seven males completed cycle exercise (42.5% V(O2peak) for 2 hours) in a hot, humid environment (38 degrees C, 60% relative humidity) on each of 2 consecutive days. Blood samples were obtained from an antecubital vein before exercise and 0 hours and 22 hours postexercise for the analysis of eHsp72. Exercise-heat stress resulted in enhanced eHsp72, with a similar absolute increase found on both days (day 1: 1.26 ng/mL [0.80 ng/mL]; day 2: 1.29 ng/mL [1.60 ng/mL]). Resting eHsp72 decreased from rest on day 1 to day 2's 22-hour postexercise sample (P < 0.05). It is suggested that the reduction in resting eHsp72 after 2 consecutive exercise-heat exposures is possibly due to an enhanced removal from the circulation, for either immunoregulatory functions, or for improved cellular stress tolerance in this initial, most stressful period of acclimation.
Full-textDOI: · Available from: Myra Nimmo, May 30, 2015
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ABSTRACT: Environmental dampness is one factor which can cause human diseases. The effects of exposure to humidity on human immune function are diverse and numerous. In the theory of traditional Chinese medicine (TCM), dampness is defined as one of the major pathogenic factors in the human body. It is divided into "external dampness" and "internal dampness." However the molecular mechanism leading to humidity-induced immunosuppression is obscure. In the present study, we investigated the expression of the T-cell antigen receptor variable β (TCRVβ) subfamilies in rats which were fed in different humid environment. And the expression levels of the TCRVβ subfamilies were detected using FQ-PCR. We found that the dampness might reduce the immunological recognition function of rats. And the obstruction of the immunological recognition function might be caused by internal dampness rather than external dampness.Evidence-based Complementary and Alternative Medicine 05/2014; 2014:373608. DOI:10.1155/2014/373608 · 2.18 Impact Factor
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ABSTRACT: The aim of this study was to determine whether short-term heat acclimation (STHA) could confer increased cellular tolerance to acute hypoxic exercise in humans as determined via monocyte HSP72 (mHSP72) expression. Sixteen males were separated into two matched groups. The STHA group completed 3 days of exercise heat acclimation; 60 minutes cycling at 50% VO2peak in 40°C 20% relative humidity (RH). The control group (CON) completed 3 days of exercise training in 20°C, 40% RH. Each group completed a hypoxic stress test (HST) one week before and 48 hours following the final day of CON or STHA. Percentage changes in HSP72 concentrations were similar between STHA and CON following HST1 (P = 0.97). STHA induced an increase in basal HSP72 (P = 0.03) with no change observed in CON (P = 0.218). Basal mHSP72 remained elevated before HST2 for the STHA group (P < 0.05) and was unchanged from HST1 in CON (P > 0.05). Percent change in mHSP72 was lower after HST2 in STHA compared to CON (P = 0.02). The mHSP72 response to hypoxic exercise was attenuated following 3 days of heat acclimation. This is indicative of improved tolerance and ability to cope with the hypoxic insult, potentially mediated in part by increased basal reserves of HSP72.BioMed Research International 01/2014; 2015. DOI:10.1155/2015/849809 · 2.71 Impact Factor
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ABSTRACT: Objectives. To estimate the water balance in a healthy population of sportspeople from Southern Spain and determine the sources of their fluid intake, evaluating the contribution of different types of drink and comparing the results by sex and province of residence. Methods. Three hundred eighty-six sportspeople (231 males, 152 females) were enrolled in the study. A questionnaire was administered to calculate nutrient intake through diet and physical activity, and anthropometric measures were taken according to ISAK standards. SPSS-15 was used for data analyses. Results. Fruit juice, tap water, bottled water, processed fruit juice, carbonated drinks, and isotonic drinks comprised 96% of the total water intake. Simple sugar consumption represented 4.44% of daily calorie intake. Significant differences were found between sexes and between professionals and amateurs. The amount of drinks consumed varied as a function of the quality of the drinking water, which significantly differed among the eight Andalusian provinces. Conclusion. This study population did not fully meet fluid intake recommendations, compliance with hydration recommendations varied as a function of the sex and the amateur or professional status of these sportspeople. The pattern of drinks consumption also differed according to their place of residence.Revista Andaluza de Medicina del Deporte 03/2013; 6(1):12-16.