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This study examined whether the exercise-increased extracellular heat shock protein 72 (eHsp72) levels in rats was associated with body temperature elevation during exercise. In all, 26 female Sprague-Dawley rats (3 mo old) were assigned randomly to control (CON; n = 8), exercise under warm temperature (WEx; n = 9), or exercise under cold temperature (CEx; n = 9). The WEx and CEx were trained at 25[degrees]C or 4[degrees]C, respectively, for nine days using a treadmill. Before and immediately after the final exercise bout, the colonic temperatures were measured as an index of body temperature. The animals were subsequently anesthetized, and blood samples were collected and centrifuged. Plasma samples were obtained to assess their eHsp72 levels. Only the colonic temperature in WEx was increased significantly (P < 0.05) by exercise. The eHsp72 level in WEx was significantly higher (P < 0.05) than that of either the CON or CEx. However, no significant difference was found between CON and CEx. Regression analyses revealed that the eHsp72 level increased as a function of the body temperature. In another experiment, the eHsp72 level of animals with body temperature that was passively elevated through similar kinetics to those of the exercise was studied. Results of this experiment showed that mere body temperature elevation was insufficient to induce eHsp72 responses. Collectively, our results suggest that body temperature elevation during exercise is important for induction of exercise-increased eHsp72. In addition, the possible role of body temperature elevation is displayed when the exercise stressor is combined with it. running exercise; warm; cold; ELISA; stress proteins

Overexpression of heat shock protein (HSP)72 is associated with cardioprotection. Hyperthermia-induced HSP72 overexpression is attenuated with senescence. While exercise also increases myocardial HSP72 in young animals, it is unknown whether this effect is attenuated with aging. Therefore, we investigated the effect of aging on exercise-induced myocardial heat shock factor (HSF)-1 activation and HSP72 expression. Male Fischer-344 rats (6 or 24 mo) were randomized to control, exercise, and hyperthermic groups. Exercise consisted of 2 days of treadmill running (60 min/day, ~75% maximal oxygen consumption). Hyperthermia, 15 min at ~41[degrees]C (colonic temperature), was achieved using a temperature-controlled heating blanket. Analyses included Western blotting for myocardial HSP72 and HSF-1, electromobility shift assays for HSF-1 activation, and Northern blotting for HSP72 mRNA. Exercise and hyperthermia increased (P < 0.05) myocardial HSP72 in both young (>3.5- and 2.5-fold, respectively) and aged (>3- and 1.5-fold, respectively) animals. Both exercise and hyperthermic induction of HSP72 was attenuated with age. Myocardial HSF-1 protein, HSF-1 activation, and HSP72 mRNA did not differ with age. These data demonstrate that aging is associated with diminished exercise-induced myocardial HSP72 expression. Mechanisms other than HSF-1 activation and transcription of HSP72 mRNA are responsible for this age-related impairment. stress proteins; cardioprotection; heart; heat shock protein

Heat shock proteins (Hsps) have a critical role in maintaining cellular homeostasis and in protecting cells from a range of acute and chronic stressful conditions. Treadmill running exercise results in increased Hsp72 and Hsp25 levels in various tissues and heat production during exercise has been shown to be the main factor for the increased levels of Hsp72 in myocardium. Since the adrenal gland plays a vital role in general response to stress, regulation of Hsps in adrenal glands following stressful events seems to be critical for controlling the whole-body stress response appropriately. This study tested the hypothesis of whether elevation of temperature is solely responsible for exercise-induced adrenal Hsp72 and Hsp25 expression. Female Sprague-Dawley rats (3 months old) were randomly assigned to either a sedentary control group or one of two treadmill-running groups: a cold exercise group run in a cold room at 4 [degrees]C (CE), and a warm exercise group run at 25 [degrees]C temperature (WE). Animals were run 60 min a day at 30 m min.sup.-1 speed for 4 consecutive days following adaptation to treadmill exercise. Exercise resulted in a significant elevation of body temperature only in the WE group (p < 0.05). Adrenal Hsp72 and Hsp25 levels were significantly higher in the WE group compare to the other groups (p < 0.05). These data demonstrated that exercise-related elevations of body temperature could be the only factor for the inductions of adrenal Hsp72 and Hsp25 expression. Keywords: Hsp72, Hsp25, Cold exercise, Adrenal, Treadmill running, Author(s): Senay Akin[sup.1], Hisashi Naito[sup.2], Yuji Ogura[sup.2], Noriko Ichinoseki-Sekine[sup.2], Mitsutoshi Kurosaka[sup.2], Ryo Kakigi[sup.2] and Haydar A. Demirel[sup.1] Introduction Sustaining of homeostasis from molecular to physiological level is important for survival [...]

The use of prohibited substances in the world of sport, in and out of competition, is a major global problem. A number of similar studies have been conducted in other parts of the world that investigate the knowledge, attitudes, and practices of athletes about doping. The results of those studies cannot entirely be extrapolated to elite Turkish athletes. Therefore, this study aimed to investigate elite athletes' current knowledge of appropriate drug use, doping and use of supplements, and to explore the need for further education on these topics. A total of 202 Turkish athletes participated in this descriptive cross-sectional study. The data were collected through a questionnaire. A five-point Likert scale was used for questions. The most commonly used over-the-counter medications by athletes were painkillers (78.2%). A remarkable proportion of athletes considered painkillers (41.1%), protein powder (43.1%), and caffeine (41.1%) to be prohibited drugs. According to the athletes, physicians (84.6%) and coaches (78.6%) were the two most frequently used sources of information, and 87.6% of the athletes found the physician to be the most reliable source of information. Elite athletes have poor knowledge about doping in Turkey. There is an urgent need for educational anti-doping programmes to address the knowledge gaps observed amongst athletes in this study. [ABSTRACT FROM AUTHOR]

Copyright of Spor Hekimligi Dergisi/Turkish Journal of Sports Medicine is the property of Turkish Journal of Sports Medicine / Spor Hekimleri Dernegi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Spor Hekimligi Dergisi/Turkish Journal of Sports Medicine is the property of Turkish Journal of Sports Medicine / Spor Hekimleri Dernegi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Spor Hekimligi Dergisi/Turkish Journal of Sports Medicine is the property of Turkish Journal of Sports Medicine / Spor Hekimleri Dernegi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Coombes, Jeff S., Scott K. Powers, Karyn L. Hamilton, Haydar A. Demirel, R. Andrew Shanely, Murat A. Zergeroglu, Chandan K. Sen, Lester Packer, and Li Li Ji. Improved cardiac performance after ischemia in aged rats supplemented with vitamin E and [Alpha]-lipoic acid. Am J Physiol Regulatory Integrative Comp Physiol 279: R2149-R2155, 2000.--The purpose of these experiments was to examine the effects of dietary antioxidant supplementation with vitamin E (VE) and [Alpha]-lipoic acid ([Alpha]-LA) on biochemical and physiological responses to in vivo myocardial ischemia-reperfusion (I-R) in aged rats. Male Fischer-334 rats (18 mo old) were assigned to either 1) a control diet (CON) or 2) a VE and [Alpha]-LA supplemented diet (ANTIOX). After a 14-wk feeding period, animals in each group underwent an in vivo I-R protocol (25 min of myocardial ischemia and 15 min of reperfusion). During reperfusion, peak arterial pressure was significantly higher (P [is less than] 0.05) in ANTIOX animals compared with CON diet animals. I-R resulted in a significant increase (P [is less than] 0.05) in myocardial lipid peroxidation in CON diet animals but not in ANTIOX animals. Compared with ANTIOX animals, heart homogenates from CON animals experienced significantly less (P [is less than] 0.05) oxidative damage when exposed to five different in vitro radical producing systems. These data indicate that dietary supplementation with VE and [Alpha]-LA protects the aged rat heart from I-R-induced lipid peroxidation by scavenging numerous reactive oxygen species. Importantly, this protection is associated with improved cardiac performance during reperfusion. aging; free radicals; lipid peroxidation; myocardial performance