Interaction of exercise training with taurine attenuates infarct size and cardiac dysfunction via Akt-Foxo3a-Caspase-8 signaling pathway.

This research aimed to investigate the synergistic protective effect of exercise training and taurine on Akt-Foxo3a-Caspase-8 signaling related to infarct size and cardiac dysfunction. Therefore, 25 male Wistar rats with MI were divided into five groups: sham (Sh), control-MI(C-MI), exercise training-MI(Exe-MI), taurine supplementation-MI(Supp-MI), and exercise training + taurine-MI(Exe + Supp-MI). The taurine groups were given a 200 mg/kg/day dose of taurine by drinking water. Exercise training was conducted for 8 weeks (5 days/week), each session alternated 2 min with 25-30% VO2peak and 4 min with 55-60% VO2peak for 10 alternations. Then, the left ventricle tissue samples were taken from all groups. Exercise training and taurine activated Akt and decreased Foxo3a. Expression of the caspase-8 gene was increased in cardiac necrosis after MI, While, after 12 weeks of intervention decreased. Results exhibited that exercise training combined with taurine has a greater effect than either alone on activating the Akt-Foxo3a-caspase signaling pathway (P < 0.001). MI-induced myocardial injury leads to increase collagen deposition (P < 0.001) and infarct size and results in cardiac dysfunction via reduced stroke volume, ejection fraction, and fractional shortening (P < 0.001). Exercise training and taurine improved cardiac functional parameters (SV, EF, FS) and infarct size (P < 0.001) after 8 weeks of intervention in rats with MI. Also, the interaction of exercise training and taurine has a greater effect than alone on these variables. Interaction of exercise training with taurine supplementation induces a general amelioration of the cardiac histopathological profiles and improves cardiac remodeling via activating Akt-Foxo3a-Caspase-8 signaling with protective effects against MI.

Interactive Effects of Swimming High-Intensity Interval Training and Resveratrol Supplementation Improve Mitochondrial Protein Levels in the Hippocampus of Aged Rats.

Mitochondrial dysfunction and increased oxidative stress cause damage to cells which can lead to the aging process and age-related diseases. Antioxidants such as resveratrol and high-intensity exercise can benefit oxidative damage prevention. This study is aimed at evaluating the effects of swimming high-intensity interval training and resveratrol on mitochondrial metabolism key proteins, SIRT5, SOD1, and PDH-E1α, and the level of NAD+ as a cofactor in the deacetylation process in aged rat hippocampus. Forty-five male Wistar rats, aged 20 months, were randomly divided into five groups: control (C), Swimming High-Intensity Interval Training (HIIT) (S-HIIT), Swimming HIIT with resveratrol supplementation (S-HIIT-R), resveratrol supplementation (R), and solvent of resveratrol supplementation (SR). S-HIIT and resveratrol groups performed the exercise and received resveratrol (10 mg/kg/day, gavage) for six weeks. Western blot analysis was performed to determine the protein level in the hippocampus. The amount of SIRT5 and SOD1 proteins in the hippocampus increased. S-HIIT with resveratrol or resveratrol alone increased the PDH-E1α level significantly. The amount of NAD+ was analyzed by assay kit that was reduced in S-HIIT, S-HIIT-R, and SR groups compared to controls. The results showed that resveratrol and S-HIIT attenuated the age-related brain changes by increasing the expression of SOD1 and SIRT5 and reducing the level of NAD+ in the hippocampus. Considering these findings, S-HIIT and resveratrol supplementation could be proposed as strategies to attenuate age-related brain changes. Resveratrol alone and exercise through the regulation of crucial proteins and cofactors can influence mitochondrial metabolism and oxidative stress in the hippocampus of aged rats.

The effects of combined resveratrol and high intensity interval training on the hippocampus in aged male rats: An investigation into some signaling pathways related to mitochondria.

Objectives: High-intensity interval training (HIIT) is a shape of interval training that provides ameliorated athletic capacity and has a good effect on health. Resveratrol is a natural polyphenol abundant in grapes and red wine and has been demonstrated to apply various useful health impacts on the body. This research aimed to evaluate the interactive effects of swimming HIIT and resveratrol consumption on SIRTs 3 & 4, NAD+/NADH, AMPK and SOD2 expression in aged rats. Materials and Methods: In total, forty-five old male albino rats (Wistar) with the age of twenty months were allocated into 5 groups randomly. Control group (Ctrl), Swimming HIIT group (Ex: Exercise), Swimming HIIT with Resveratrol consumption group (R+Ex), Resveratrol consumption group (R) and solvent of resveratrol consumption group (vehicle). R+Ex group accomplished the exercise and consumed resveratrol (10 mg/kg/day, gavage) for 6 weeks. Results: HIIT & resveratrol significantly increased NAD+/NADH, SOD 2 and AMPK in the aged rats. HIIT increased SIRT3, but resveratrol reduced it. As for SIRT4, HIIT decreased it, while resveratrol positively affected it. Conclusion: Resveratrol and HIIT, especially their combination, have anti-oxidant and anti-aging effects on the hippocampus of old rats.

A Comparison of the Effect of Two Types of Continuous and Discontinuous Aerobic Exercise on Patients' Stem Cell Mobilization before Autologous Hematopoietic Stem Cell Transplantation.

Background: Transplant success largely depends on the number of hematopoietic stem cells. The release of catecholamines following exercise can, as a treatment in addition to medication, affect the mobilization of stem cells from the bone marrow into the peripheral blood. The aim of the present study is to compare two types of aerobic exercise on stem cell mobilization before autologous transplantation. Materials and Methods: In a quasi-experimental applied study, 60 patients in the age range of 22-69 years referred to Taleghani Hospital were randomly selected and assigned into 3 groups of 20 members (continuous aerobic, discontinuous aerobic and control group). Aerobic exercise program was performed for 7 consecutive days of mobilization period including walking on a treadmill (according to the patient's ability) continuously and discontinuously for 30 minutes in the morning and afternoon. Blood samples were taken the morning before and after mobilization and the CD34 and MNC levels were counted as absolute. Chi-square test, paired t-test, analysis of covariance (ANCOA) and multiple comparison test were used for statistical analysis. All analyses were considered significant at p ≤ 0. Results: Moderate-intensity continuous and discontinuous aerobic activity increases the number of CD34 and MNC cells. A comparison between continuous and discontinuous aerobic activity showed an increase in the amount of these cells. The continuous aerobic activity group was found to have a statistically significant increase compared to the discontinuous group (P≤0.05). Conclusion: Moderate intensity continuous and discontinuous aerobic exercise significantly increased hematopoietic stem cells. However, this increase was greater as a result of continuous aerobic exercise than discontinuous exercise. Regarding the potential role of these cells in transplantation, they could possibly help the transplant process.

Targeting necroptotic cell death pathway by high-intensity interval training (HIIT) decreases development of post-ischemic adverse remodelling after myocardial ischemia / reperfusion injury.

Regulated necrosis (necroptosis) plays a pivotal role in the extent of cardiomyocyte loss and the development of post-ischemic adverse remodelling and cardiac dysfunction following myocardial I/R injury. Although HIIT has been reported to give rise to cardioprotection against MI, but the detailed knowledge of its molecular targets for treatment of MI is still not available. The LAD of Male Wistar rats was occluded to induce MI for 30 min and reperfusion for eight weeks. We investigated the effect of long-term HIIT for eight weeks on lipid peroxidation, SOD activity and GSH content using ELISA assay. Cardiac function, fibrosis, and infarct size were assessed by echocardiography, Masson's trichrome and Evans Blue/TTC dual staining respectively. The expressions of gene markers of myocardial hypertrophy, fibrosis and key mediators of necroptosis were measured using RT-PCR and western blotting assay respectively. The results indicated that HIIT reduced lipid peroxidation, infarct size and improved endogenous antioxidant system and heart function. Significant decreases in mRNA levels of procollagen α1(I), α1(III), and fibronectin1were observed following HIIT. Moreover, that HIIT significantly decreased the expression of key mediators of necroptosis induced by MI (P < 0.05). There were no significant differences in ß-MHC mRNA level in different groups. The findings of study suggest that HIIT might exert cardioprotective effects against post-ischemic adverse remodeling through targeting necroptosis process. Likewise, cardioprotective effects of HIIT in coping with myocardial I/R injury may be associated with RIP1-RIP3-MLKL axis. These findings establish a critical foundation for higher efficiency of exercise-based cardiac rehabilitation post-MI and future research.

Consistency between Sweat Rate and Wet Bulb Globe Temperature for the Assessment of Heat Stress of People Working Outdoor in Arid and Semi-arid Regions.

BACKGROUND: Heat stress is common among workers in arid and semi-arid areas. In order to take every preventive measure to protect exposed workers against heat-related disorders, it is crucial to choose an appropriate index that accurately relates environmental parameters to physiological responses. OBJECTIVE: To investigate the consistency between 2 heat stress and strain indices, ie, sweat rate and wet bulb globe temperature (WBGT), for the assessment of heat stress of people working outdoor in arid and semi-arid regions in Iran. METHODS: During spring and summer, 136 randomly selected outdoor workers were enrolled in this study. Using a defined protocol, the sweat rate of these workers was measured 3 times a day. Simultaneously, the environmental parameters including WBGT index were recorded for each working station. RESULTS: The level of agreement between sweat rate and WBGT was poor (κ<0.2). Based on sweat rate, no case exceeding the reference value was observed during the study. WBGT overestimated the heat stress in outdoor workers compared to sweat rate. CONCLUSION: It seems that the sweat rate standards may need some modifications related to real condition of work in arid and semi-arid regions in Iran. Moreover, it seems that judging workers solely based on monitoring their sweat rate in such regions, can probably result in underestimation of heat stress.

The cut-off point for tympanic temperature as a heat strain index for evaluation of outdoor workers: a field study.

OBJECTIVES: The aims of this study were (a) to assess the agreement coefficient between tympanic temperatures and the most popular and valid heat stress index, wet bulb globe temperature (WBGT), in outdoor environments; (b) to determine a cut-off point for tympanic temperature as a heat strain index for evaluation of outdoor workers. METHODS: 1452 measurements of WBGT index and tympanic temperature were recorded for outdoor workers from nine different climatic regions. Consistency of the WBGT and tympanic temperature were tested. The cut-off point for tympanic temperature in outdoor environments regarding WBGT evaluation was suggested based on obtained sensitivity and specificity from a receiver operating characteristic curve. RESULTS: The results showed that there were numerous situations in which WBGT exceeded the reference value, whilst the measured values of tympanic temperature rarely reached a permissible value for core temperature (38 °C). Therefore, appropriate consistency of results between the heat stress and strain indices was not achieved. CONCLUSION: The criterion of tympanic temperature equaling 37 °C was suggested as a cut-off point for tympanic temperature as a heat strain index for outdoor environment evaluation.

Effects of exercise prior or during pregnancy in high fat diet fed mice alter bone gene expression of female offspring: An experimental study.

BACKGROUND: Based on different studies it was shown that exercise training is an important factor in preconception and prenatal care. OBJECTIVE: The aim of this study was to determine whether regular preconception exercise training with or without exercise training during pregnancy decreases detrimental effects of maternal high fat diet on female offspring bone health. MATERIALS AND METHODS: Twenty-four C57BL/6 female mice were fed high-fat diet (35%) and were randomly divided into four groups: trained in preconception period and exercised during pregnancy (TE); trained in preconception periods but unexercised during pregnancy (TC); untrained in preconception periods but exercised during pregnancy (CE); untrained and unexercised (CC). Trained mice were subjected to a protocol of moderate endurance exercise training over a period of 4 weeks before pregnancy. TE and CE Dams groups had access to wheels throughout pregnancy until delivery. Analyses were performed on the female offspring that did not have access to running wheels or exercise training during any portion of their lives. The relative expression levels of ß-catenin, Peroxisome proliferator-activated receptor Æ´ (PPARÆ´), osteoprotegerin (OPG), and Receptor activator of nuclear factor NF-kB ligand (RANKL) were determined by Quantitative RT-PCR (qPCR). RESULTS: Exercise during pregnancy in isolation had no effect on any measure genes but exercise both before and during pregnancy affected all genes. Exercise only before pregnancy increased ß-catenin and OPG and decreased PPARÆ´, RANKL, and RANKL/OPG ratio (p<0.001). CONCLUSION: This study demonstrated that maternal exercise training before and during pregnancy may modulate the risk of bone disorders in offspring of mothers fed a high-fat diet.

Determination of Air Enthalpy Based on Meteorological Data as an Indicator for Heat Stress Assessment in Occupational Outdoor Environments, a Field Study in IRAN.

BACKGROUND: Heat stress evaluation and timely notification, especially using meteorological data is an important issue attracted attention in recent years. Therefore, this study aimed at answering the following research questions: 1) can enthalpy as a common environmental parameter reported by meteorological agencies be applied accurately for evaluation of thermal condition of outdoor settings, and 2) if so, what is it's the best criterion to detect areas in stress or stress-free situations, separately. METHODS: Nine climatic regions were selected throughout Iran covering a wide variety of climatic conditions like those, which exist around the world. Three types of parameters including measured (ta, RH, Pa and WBGT), estimated (metabolic rate and cloth thermal insulation), and calculated parameters (enthalpy and effective WBGT) were recorded for 1452 different situations. Enthalpy as a new indicator in this research was compared to WBGT in selected regions. RESULTS: Altogether, a good consistency was obtained between enthalpy and WBGT in selected regions (Kappa value: 0.815). Based on the good ROC curve obtained using MedCal software, the criterion of the values more than 74.24 for the new index was determined to explain heat stress situation for outdoor environments. CONCLUSIONS: Because of simplicity in measurement, applicability of the indicator for weather agencies, the consistency observed between enthalpy and a valid as well as accurate index (WBGT), sensor requirements which take only a few seconds to reach equilibrium and so on, enthalpy indicator can be introduced and applied as a good substitute for WBGT for outdoor settings.

Cardioprotective Effect of High Intensity Interval Training and Nitric Oxide Metabolites (NO2 (-), NO3 (-)).

BACKGROUND: The aim of this study was to investigate the effects of High-Intensity Interval Training (HIIT) on nitric oxide metabolites (NO2(-), NO3(-)) and myocardial infarct size after Ischemia/Reperfusion (I/R) injury in healthy male rats. METHODS: A total of 44 Wistar rats were randomly divided into 4 groups including HIIT (n=8), HIIT + IR protocol (n=14), control (n=8), and control + IR (n=14). Each training session of HIIT consisted of 1 hour of exercise in three stages: 6-minute running at 50-60% VO2max for warm-up; 7 intervals of 7-minute running on treadmill with a slope of 5° to 20° (4 minutes with an intensity of 80-100% VO2max and 3 minutes at 50-60% VO2max); and 5-minute running at 50-60% VO2max for cool-down. The control group did not participate in any exercise program. Nitric Oxide (NO) and its metabolites were measured by using Griess reaction test. RESULTS: The results showed that eight weeks of exercise training exerted a significantly increasing effect on nitrite (8.55 µmol per liter, equivalent to 34.79%), nitrate (62.02 µmol per liter, equivalent to 149.48%), and NOx (66 µmol per liter, equivalent to 98.11%) in the HIIT group compared with the control group. The results showed myocardial infract size (IS) was significantly smaller (23.2%, P<0.001) in the exercise training group compared with the control group. CONCLUSION: Incremental changes in NO-NO3 (-), NO2 (-) axis are one of mechanisms through which HIIT program can protect the heart from I/R injury and decrease myocardial infarction.

Outdoor occupational environments and heat stress in IRAN.

BACKGROUND: The present study aimed at demonstrating the heat stress situation (distribution and intensity) based on a standard and common heat stress index, Wet Bulb Globe Temperature (WBGT), during hot seasons and interpret the obtained results considering global warming and rising temperature in different parts of the country based on climate changes studied in Iran. METHODS: Heat stress assessment was done using WBGT index. Environmental parameters were measured simultaneously in the early, middle and end of shift work. The personal parameters including cloth thermal insulation and metabolic rate of 242 participants from 9 climatic categories were recorded for estimating effective WBGT (measured WBGT plus cloth adjustment factor as well as metabolic rate effect). The values of the indicator were categorized in the statistical software media and then linked to the climatic zoning of the data in the GIS information layers, in which, WBGT values relating to selected stations were given generalization to similar climatic regionalization. RESULTS: The obtained results showed that in the summer about 60 % and more than 75 % of the measurements relating to 12 pm and 3 pm, respectively, were in heat stress situations (i.e. the average amount of heat stress index was higher than 28 °C). These values were found to be about 20-25 % in the spring. Moreover, only in the early hours of shift work in spring could safe conditions be seen throughout the country. This situation gradually decreased in the middle of the day hours and was replaced by the warning status and stress. And finally, in the final hours of shift work thermal stresses reached their peaks. These conditions for the summer were worse. CONCLUSIONS: Regarding several studies related to climate change in Iran and the results of present study, heat stress, especially in the central and southern parts of Iran, can be exacerbated in the decades to come if climate change and rising temperature occurs. Therefore, paying attention to this critical issue and adopting macro-management policies and programs in the field of workplace health is essential.

Prevalence of underweight, overweight and obesity in preschool children of Tehran, Iran.

BACKGROUND: It is reported that prevalence of overweight and obesity have increased in all age groups, but little is known about prevalence of overweight and obesity in preschool children. Therefore, the purpose of this study was to survey the prevalence of underweight, overweight and obesity in 3-6 year-old Tehranian children in 2009-2010. METHODS: This cross-sectional study was performed on a total of 756 (378 boys and 378 girls) preschool children aged 3-6. Subjects were selected through stratified sampling from 5 geographic regions of Tehran (east, west, north, south, and center). Body weight and height were measured directly. Underweight, overweight and obesity was defined as Body Mass Index (BMI) ≤ 5(th) percentile (underweight), 5(th) to 85(th) percentile (normal weight), 85(th) to 95(th) percentile (overweight), and > 95(th) percentile (obesity); based on recommendation of Centers for Disease Control (CDC) in 2000. RESULTS: Findings showed that the prevalence of underweight, overweight and obesity was 4.77%, 9.81% and 4.77% in boys and 4.77%, 10.31% and 4.49% in girls, respectively. CONCLUSIONS: Our findings showed a relatively high prevalence of overweight and obesity in Tehranian preschool children that is a serious problem. This result can be used in clinical setting and preventive programs.

Influence of a physical fitness course on menstrual cycle characteristics.

AIM: Exercise is commonly cited as a remedy for menstrual symptoms. The purpose of the present study was to evaluate the effect of a period of exercise on physical and psychological symptoms of menstruation, dysmenorrhea, oligomenorrhea and amenorrhea. METHODS: Participants of the study were 250 students of Shiraz University who enrolled in a fitness course. The study design was semi-experimental with one group. Prior and after 12 weeks of a physical fitness program, our subjects completed questionnaires on menstrual distress. The physical fitness training program included physical fitness exercises (cardiovascular endurance, muscular endurance, agility, speed, strength; duration: 90 min, frequency: twice weekly, intensity: 50 to 70% of maximum heart rate). The t test was used for analysis of the data. RESULTS: Physical premenstrual symptoms (p = 0.005), psychological premenstrual symptoms (p = 0.019), dysmenorrhea (p = 0.0001) and oligomenorrhea (p = 0.034) were significantly reduced after the training program. There was no difference in the incidence of amenorrhea before and after the training program (p = 0.162). CONCLUSION: Our findings indicate that selected physical fitness exercises positively influenced menstrual symptoms.