Interaction between high-intensity interval training and high-protein diet on gut microbiota composition and body weight in obese male rats.

Diet and exercise are two critical factors that regulate gut microbiota, affecting weight management. The present study investigated the effect of 10 weeks of high-intensity interval training (HIIT) and a high-protein diet (HPD) on gut microbiota composition and body weight changes in obese male Wistar rats. Forty obese rats were randomly divided into five groups, including HPD, HIIT + HPD, HIIT + high-fat diet (HFD) (continuing HFD during intervention), obese control 1 (continuing HFD during intervention), obese control 2 (cutting off HFD at the beginning of the intervention and continuing standard diet), and eight non-obese Wistar rats as a non-obese control (NOC) group (standard diet). Microbial community composition and diversity analysis by sequencing 16S rRNA genes derived from the fecal samples, body weight, and Lee index were assessed. The body weight and Lee index in the NOC, HIIT + HFD, HPD, and HIIT + HPD groups were significantly lower than that in the OC1 and OC2 groups along with the lower body weight and Lee index in the HPD and HIIT + HPD groups compared with the HIIT + HFD group. Also, HFD consumption and switching from HFD to a standard diet or HPD increased gut microbiota dysbiosis. Furthermore, HIIT along with HFD increased the adverse effects of HFD on gut microbiota, while the HIIT + HPD increased microbial richness, improved gut microbiota dysbiosis, and changed rats' phenotype to lean. It appears that HFD discontinuation without doing HIIT does not improve gut microbiota dysbiosis. Also, the HIIT + HFD, HPD, and HIIT + HPD slow down HFD-induced weight gain, but HIIT + HPD is a more reliable strategy for weight management due to its beneficial effects on gut microbiota composition.

Hydroalcoholic extract of dill and aerobic training prevents high-fat diet-induced metabolic risk factors by improving miR-33 and miR-223 expression in rat liver.

Exercise training and medicinal herb supplementation may improve microRNAs (miRNAs) expression associated with obesity. This study aimed to assess the effects of 10 weeks of aerobic training (AT) and dill extract (DE) on miR-33 and miR-223 expression of liver in high-fat diet (HFD)-induced obese rats. Forty male Wistar rats were fed a defined high-fat (n = 32) and standard (n = 8, nonobese control [NC]) diet. After obesity induction, obese rats were randomly allocated to four groups: AT, DE, AT + DE, and obese control (OC). Rats were euthanized and plasma and liver tissue samples were collected after the intervention. The liver expression of miR-33 was lower in the AT, DE, AT + DE, and NC groups compared with the OC group. Also, the liver miR-223 expression was higher in the AT, DE, AT + DE, and NC groups compared with the OC group. Moreover, the liver expression of miR-223 in the AT + DE group was higher compared with the AT and DE groups. The AT, DE, AT + DE, and NC groups had lower liver TC compared with the OC group. Also, the plasma level of apolipoprotein B (Apo B) was significantly lower, and liver HDL-C was significantly higher in the AT + DE and NC groups compared with the OC group. These findings show that long-term AT combined with the intake of DE may improve the plasma levels of Apo B, and TC and HDL-C levels in the liver, which is probably due to AT and DE positive effects on miR-33 and miR-223 in the liver of obese rats. PRACTICAL APPLICATIONS: Aerobic training reduces overweight and obesity health problems, however, the duration and intensity of the exercise training distinguish between individuals. We used an integrated approach combining pharmacological and non-pharmacological as a medical strategy to prevent HFD-induced metabolic injury in obese rats. The present results discovered that a combination of AT + DE intervention improves the miR-33 and miR-223 in the liver of obese rats.

Gym and home-based combined training in men with primary hypertension: are they equally effective on functional fitness profile, body composition components, and biochemical parameters of hypertension?

OBJECTIVE: This study aimed to compare the effects of 10 weeks of gym versus home-based combined training on the functional fitness, body composition, and biochemical parameters of hypertension in primary hypertensive men. METHODS: Forty-six patients (age 48 ± 9 years, BMI 30 ± 4 kg/m2) assigned into three groups: a gym-based combined training (GBCTr: n = 16; resistance at 60-80% of 1RM, using pin-loaded resistance equipment, aerobic at 40-60% HRR, and stretching), home-based combined training (HBCTr: n = 15; resistance at 12-15 RPE, using an elastic exercise band, aerobic at 40-60% HRR, and stretching), and control (CTR, n = 15). RESULTS: Following GBCTr and HBCTr, the functional aerobic capacity (P = .005 and P = .004, respectively), flexibility (P = .01 and P = .004, respectively), and lower limb muscle strength (P = .01 and P = .02, respectively) was increased significantly compared with the CTR group. The body weight (P = .02), body mass index (P = .008), hip circumference (P = .02), and nitric oxide level in GBCTr and HBCTr group (P = .002 and P = .02, respectively) was decreased significantly compared with the CTR group. No significant changes found in the plasma levels of NADPH oxidase 5, thioredoxin-2, thioredoxin reductase-2, and resting blood pressure after GBCTr and HBCTr compared with the CTR group. CONCLUSION: These results suggest that in hypertensive men, HBCTr equally to GBCTr improved functional fitness and body composition remarkably without necessarily reducing resting blood pressure. Therefore, they can be advisable substitutes for gaining health benefits.

Aerobic training and hydroalcoholic extracts of green tea improve pro-oxidant-antioxidant balance and histopathological score in the N-methyl-N-nitrosourea-induced prostate cancer model of rat.

Green tea is a main resource for catechins. Catechins as antioxidant compounds reduce the production of reactive oxygen species and they have a protective role in the development of cancer. As well as, aerobic exercise change free radicals with two contradictory mechanisms. Aerobic training promotes excessive production of free radicals resulting in oxidative stress. In contrast, it increases the total antioxidant capacity. In this study, effect of aerobic training and hydroalcoholic extract of green tea (HEGT) on the pro-oxidant-antioxidant balance (PAB), prostate-specific antigen (PSA) and histopathological score of cancerous tissue in the N-methyl-N-nitrosourea-induced prostate cancer was investigated. A rat model of prostate cancer was induced by hormonal change and N-Nitroso-N-methylurea (NMU). HEGT 0.1 % and 45 min of aerobic exercise in 5 days a week for eight weeks were scheduled. The presence of major catechins was approved using GC-MS. Histological study, PAB and PSA levels were used to monitor the preventive role of treatments. The prostate weights of cancerous rats were significantly higher than healthy controls (P<0.05). The PAB was only significantly higher in cancerous rats and cancerous rats receiving aerobic exercise (P<0.05). The mean of histological score of cancerous tissue was reduced in rat receiving HEGT and both HEGT and aerobic exercise. The amounts of PSA level did not significantly differ between the groups of this study (P>0.05). Our results provided laboratory and histological documentation for the preventive role of green tea extract in developing prostate cancer via its potential to re-establish the pro-oxidant-antioxidant balance.

How to exercise to increase lipolysis and insulin sensitivity: Fasting or following a single high-protein breakfast.

BACKGROUND: The purpose of this study was to investigate the lipolysis response and insulin sensitivity to high-intensity interval exercise (HIIE) upon fasting (HIIEFAST) and following the intake of a high-protein breakfast (HIIEHPFED). METHODS: Overweight men participated in two sessions of HIIE after an overnight fast and post-HPFED with an interval of one week. Metabolic biomarkers were assessed before, immediately after, and 3h postexercise. To evaluate the metabolic effects of HIIE, two-way repeated-measures ANOVA was used. RESULTS: Glycerol levels increased immediately after HIIEFAST and HIIEHPFED (P=0.0001) and decreased 3h after exercise in both states (P=0.001). There were no significant changes in free fatty acid (FFA) levels immediately after exercise, but a significant increase was observed 3h after exercise compared to the baseline and immediately after exercise in HIIEFAST and HIIEHPFED (P=0.0001). Insulin sensitivity was increased for 3h after HIIEHPFED compared to the baseline and immediately after exercise (P=0.04). CONCLUSIONS: These findings suggest that fasting during exercise is not necessary for the greater stimulation of lipolysis and an increase in insulin sensitivity and that exercise following a high-protein breakfast can have a similar effect in overweight young men.

High-Intensity Training and Saffron: Effects on Breast Cancer-related Gene Expression.

PURPOSE: Exercise training and some herbal components have an anticancer function and can suppress tumor growth. However, the role of these protective factors in altering breast cancer-related gene expression is still unknown. Thus, this study aimed to assess the effect of 4 wk of high-intensity interval training (HIIT) and saffron (Crocus sativus L.) aqueous extract (SAE) on Sirtuin-1 (SIRT1), human telomerase reverse transcriptase (hTERT), and p53 gene expression in female mice breast tumor tissue induced by 4T1 cell line. METHODS: This study was performed on female BALB/c mice. The 4T1 breast cancer cells were subcutaneously implanted, and mice were randomly sorted into the following groups: control, HIIT, SAE, HIIT + SAE (n = 10 mice per group), and sham (n = 4 mice per group). Mice were sacrificed at the end of the intervention period, and the expression of SIRT-1, hTERT, and p53 was determined by real-time polymerase chain reaction. RESULTS: The mRNA level of SIRT1 was increased in the HIIT + SAE group compared with the HIIT and control groups (P = 0.007 and P = 0.03, respectively). Moreover, the amount of mRNA of p53 was increased after a 4-wk HIIT compared with the control and HIIT + SAE groups in tumor tissue (P = 0.03 and P = 0.02, respectively). No change was found in the mRNA expression of hTERT between groups (P = 0.92). CONCLUSIONS: These findings suggest that HIIT may reduce tumor burden through the upregulation of p53 associated with tumor suppression pathway. In contrast, the combination of HIIT and SAE did not alter p53 and SIRT1 expression levels and may suppress tumor growth by other mechanisms.

The effects of high-intensity interval training and saffron aqueous extract supplementation on alterations of body weight and apoptotic indices in skeletal muscle of 4T1 breast cancer-bearing mice with cachexia.

Exercise training and antioxidant supplementation may improve unintentional weight loss and programmed cell death associated with cancer cachexia. The aim of this study was to examine the alterations of body weight and apoptotic indices in skeletal muscle of 4T1 breast cancer-bearing mice with cachexia following 4 weeks of high-intensity interval training (HIIT) and saffron aqueous extract (SAE) supplementation. Female BALB/c mice following induction of breast cancer were divided into (i) controls, (ii) HIIT, (iii) SAE, (iv) HIIT+SAE, and (v) sham groups. Mice were euthanized and gastrocnemius muscle was collected after intervention. The control group elicited a significant weight reduction during third and fourth weeks of tumor injection, while other treatments such as HIIT and SAE, but not HIIT+SAE, showed that they counteracted this adverse event. Furthermore, HIIT and SAE treatments (not HIIT+SAE) demonstrated reduced caspase-3 and Bax levels compared with the control group. The level of Bcl-2 was elevated following both HIIT and SAE treatments compared with the control group. Finally, the ratio of Bcl-2 to Bax was significantly higher in both HIIT and SAE groups, but was lower in HIIT+SAE group compared with sham group. It is likely that either HIIT or SAE intervention alone (not HIIT+SAE) represents a readily applicable approach in the regulation of muscle wasting and apoptosis in cancer cachexia. Novelty HIIT is associated with a reduced risk of cancer-related muscle wasting. SAE enhances the improvement of muscle loss and apoptotic indices. Combination of HIIT and SAE does not improve cancer-related loss of muscle mass and mediate apoptotic activation.

Sex Differences in antiaging response to short- and long-term high-intensity interval exercise in rat cardiac muscle: Telomerase activity, total antioxidant/oxidant status.

Cardiovascular disease prevails with age which varies according to sex. Telomere length plays an important role in aging. Despite the great benefits of high-intensity interval training (HIIT), the acute responses to HIIT with different intervals have not been elucidated in different sexes. This study was conducted to investigate the sex-dependent responses of telomerase enzyme activity, total oxidant status (TOS), total antioxidant capacity (TAC), and the ratio of TAC/TOS to short- and long-term high-intensity interval exercise (HIIE) in cardiac muscle of male and female rats. Forty adult Wistar rats were randomly allocated to six groups: male and female HIIE with short-term intervals (MHIIESh and FHIIESh, respectively), male and female HIIE with long-term intervals (MHIIEL and FHIIEL, respectively), and controls groups. Telomerase activity, TAC, and TOS levels were examined immediately after exercise in the cardiac muscle. The level of telomerase enzyme activity, TOS level, and the ratio of TAC/TOS did not change after HIIE with short-term interval and HIIE with long-term interval (HIIEL) in male and female rats (P = 0.52, 0.69, and 0.08, respectively). There was a statistically significant decrease in the TAC level in the MHIIESh group (P = 0.04). Furthermore, a significant decrease was observed in the HIIEL in both male and female rats (P = 0.03 and 0.04, respectively). Acute exposure to HIIE with short- and long-term intervals would not result in a significant change in some indicators of biological aging. However, due to gender-specific biological differences, further studies will provide evidence regarding the roles of HIIE at different times of intervals, which contribute to aging prevention.

High-intensity interval training with long duration intervals is more effective than short duration intervals for improving glycolytic capacity in the rats' gastrocnemius muscle.

Background There is little data regarding the ability of high-intensity interval training (HIIT) to increase of glycolytic capacity and intramuscular metabolic adaptations. The goal of this study was to evaluate the effects of HIIT (8 weeks, 5 times/week) with short (HIIT1 min: 16 × 1 min work and active recovery at 80-95% and 50-60% VO2max, respectively) and long (HIIT4 min: 4 × 4 min work and active recovery at 80-95% and 50-60% VO2max, respectively) duration intervals and 4 weeks detraining on the levels of phosphofructokinase (PFK), glycogen synthase 1 (GYS1), monocarboxylate transporter 4 (MCT4) and lactate dehydrogenase (LDH) activity in the rats' gastrocnemius muscle. Materials and methods Fifty-four male Wistar rats were assigned into three groups, including HIIT1 min, HIIT4 min and control (Ctrl). After 48 h of the last training session and after 4 weeks of detraining, the rats were sacrificed, and the gastrocnemius muscles were isolated. Results The PFK levels in the HIIT4 min group was significantly higher than in the HIIT1 min and Ctrl groups, and after the detraining period in the HIIT4 minDT group significantly decreased compared to the HIIT4 min group. The LDH activity in the HIIT4 min and HIIT1 min groups were significantly higher than the Ctrl group and the increasing trend in the HIIT4 min group was more than the HIIT1 min group. There was no significant change in LDH activity after detraining compared to training. No significant changes were observed in the level of GYS1 and MCT4 after HIIT. Conclusions Eight weeks of HIIT with long duration intervals induced more improvements in intramuscular glycolytic capacity than a short duration. After short-term detraining, some of these adaptations have remained.

Aerobic Training and Green Tea Extract Protect against N-methyl-N-nitrosourea-induced Prostate Cancer.

INTRODUCTION: Aerobic training and green tea extract can be used to reduce the risk of prostate cancer. The goal of this study was to evaluate the effects of 8-wk aerobic exercise training and administration of green tea extract on the level of nuclear factor kappa B (NF-kB), cyclooxygenase-2 (COX-2) and p53 tumor suppressor protein (p53) in prostate of rats which were stimulated by N-methyl-N-nitrosourea to induce the prostate cancer. METHODS: Sixty adult male Wistar rats were assigned into six groups including healthy control, cancer control (CCt), cancer training (CTr: 45 min·d at low to moderate intensity, five times per week, 8 wk), cancer extract (CEx: 1.34 mL of green tea extract, three times per week, 8 wk), cancer training+ cancer extract (CTr + CEx) and sham groups. Rats were sacrificed 48 h after the last intervention session, and the prostate tissue was isolated to measure the levels of NF-kB, COX-2, and p53. RESULTS: The NF-kB level in CCt group was increased significantly compared to the healthy control (P = 0.02). In the CTr group, NF-kB level was decreased significantly compared to the CCt and CEx groups (P = 0.001 and 0.05, respectively). In addition, the levels of P53 protein were reduced in CTr, CEx, and CTr + CEx groups compared to CCt group (P = 0.001, 0.02 and 0.004, respectively). No significant changes were found in the level of COX-2 between groups. CONCLUSIONS: These results suggest that a long-term exercise training combined with the intake of green tea extract may reduce levels of NF-kB and p53 in rats with prostate cancer. Given the importance of recognizing complementary therapies in this regard, future studies are warranted.

The response of meteorin-like hormone and interleukin-4 in overweight women during exercise in temperate, warm and cold water.

Background Meteorin-like hormone (Metrnl) and interleukin-4 (IL-4) are protein molecules that stimulate the production of brown adipose tissue to improve diseases such as type 2 diabetes and obesity. The aim of this study was to investigate the response of Metrnl protein and IL-4 in overweight women during exercise in temperate, warm and cold water. Materials and methods Thirteen overweight young women (mean age 25.21 ± 3.27 years, body mass index 26.43 ± 1.34 kg/m2) were selected randomly and performed three sessions of interval exercise (40 min per session, 65% of maximum oxygen consumption) in non-consecutive days in temperate (24-25 °C), warm (36.5-37.5 °C) and cold (16.5-17.5 °C) water. Blood sampling was done immediately before and after exercise. Results The Metrnl level significantly increased after exercise in temperate and warm water (p = 0.0001) and significantly decreased in cold water (p = 0.0001). IL-4 level significantly increased after exercise in warm water (p = 0.003), while there was no significant change after exercise in temperate and cold water. Conclusions Exercise in warm water appears to stimulate and accumulate immune cells compared to temperate and cold water. This feature can be used to stimulate the production of hormones such as Metrnl and IL-4 to enhance brown fat, although more studies are needed in this regard.

The effect of 12 weeks of aerobic training on serum levels high sensitivity C-reactive protein, tumor necrosis factor-alpha, lipid profile and anthropometric characteristics in middle-age women patients with type 2 diabetes.

AIMS: The aim of this study was to investigate the effect of 12 weeks of aerobic training on serum levels of high sensitivity C- reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), lipid profile and anthropometric characteristics in middle-aged women patients with type-2 diabetes. METHODS: A quasi-experimental study, 20 women patients with type-2 diabetes (mean age, 50.25 ±â€¯4.36 years, Body mass index, 25.51 ±â€¯2.91 kg/m2, and body fat percentage 23.67 ±â€¯3.05%) were randomly categorized into two experimental and control groups. The protocol aerobic training included eight-minute jogging and eight-minute running with 75-85 percent maximum heart rate reserve in the first session. Per both sessions, one minute added to running time and it increased up to 32 min after 12 weeks. Blood sampling and anthropometric measurements, 24 h before and 48 h after the last training session were conducted. RESULT: The result showed a significant reduction in hs-CRP and TNF-α in the experimental than control group (P = 0.01). Exercise training-treated patients showed a significant decrease in TG, LDL and increase HDL in comparison with baseline and the control group (P < .05). The results also showed a significant decrease in weight, body mass index, body fat percentage, and waist-hip ratio (P values 0.02, 0.03, 001, 0.04 respectively) following the 12 weeks aerobic training. CONCLUSION: It seems that long-term aerobic training, improved some important anthropometric and biochemical parameters in patients with type-2 diabetes. These observations give a new insight into the mechanisms by which aerobic training can reduce the cardiovascular risk in diabetes.

Effects of circuit resistance training intensity on the plasma ghrelin to obestatin ratios in healthy young women.

BACKGROUND: Ghrelin and obestatin are orexigenic and anorexigenic peptides, respectively. It appears that an accurate balance between theses peptides is important for regulating energy homeostasis and body weight. OBJECTIVES: The aim of this study was to identify the possible mechanisms by which circuit resistance training influences energy homeostasis and weight control. PATIENTS AND METHODS: Twenty-seven female students with the mean age of 22 ± 1.54 years and mean body mass index (BMI) of 20.76 ± 1.86 kg/m(2) were selected and randomly divided into experimental and control groups. Subjects performed circuit resistance training with 40% and 80% of 1 repetition maximum (1RM) for 4 weeks. Total plasma ghrelin, obestatin, and glucose levels and the ghrelin to obestatin ratio were measured for all subjects before and after training. RESULTS: One-way ANOVA tests showed that, the plasma ghrelin to obestatin ratio increased significantly in the 80% 1RM group (P < 0.05). Furthermore, a significant reduction of the plasma obestatin level was found in this group (P < 0.05). CONCLUSIONS: It appears that an energy deficit caused by circuit resistance training in 80% of the 1RM group resulted in the ghrelin precursor being increasingly used for ghrelin production. Thus, obestatin secretion decreased and the ghrelin to obestatin ratio increased in order to stimulate food intake and lost energy resource consumption to eventually restore the energy balance in the body.

A single session of circuit-resistance exercise effects on human peripheral blood lymphocyte ABCA1 expression and plasma HDL-C level.

ATP-binding cassette transporters transfer a variety of substrates across the lipid bilayers in an energy-dependent manner. ABCA1 is a member of this family which plays a crucial role in plasma HDL-C metabolism. The purpose of this study was to investigate ABCA1 expression in lymphocytes, plasma lipids and lipoprotein levels in response to a single session of circuit-resistance exercise. Twenty female students volunteered and randomly assigned to control, 40%, 60%, 80% one-repetition maximum groups. Subjects performed a single session of CRE (9 exercises, 25s per exercise, 3 sets of 3 non-stop circuits, and 1 min rest between the sets). Blood mononuclear cells were isolated for ABCA1 mRNA expression. Plasma glucose, lipids and lipoprotein concentrations were measured. Lymphocyte ABAC1 mRNA expression was significantly (P < 0.001) increased in all given exercise intensities. Total WBC, lymphocyte, neutrophil, platelet counts, plasma glucose, and triglyceride concentrations were also significantly increased after exercise. Changes in plasma HDL-C, LDL-C and TC, concentrations were not significant. In conclusion, a single session of CRE increased PBL ABCA1 expression that was more pronounced in 60% and 40% 1RM groups but not accompanied with significant changes in HDL-C concentrations. Thus, CRE with moderate intensities provide bigger increases of PLB ABCA1 expression not plasma HDL-C levels.

Plasma visfatin is increased after high-intensity exercise.

BACKGROUND/AIMS: Visfatin is a newly characterized protein that is highly expressed in visceral adipose tissue and may play a role in insulin resistance. We investigated the effects of repeated short bouts of high-intensity exercise on plasma visfatin and related metabolic responses. METHODS: Six young, physically fit men (22.8 +/- 2.3 years; 78.5 +/- 2.3 kg; and body mass index 22.1 +/- 1.2) performed a single session of a running-based anaerobic sprint exercise (7 sets of 6 x 35 m every 10 s, with 1 min rest between sets). Venous blood samples were collected before, immediately after, and 45 and 90 min after exercise to assess plasma visfatin, insulin, glucose, lactate and glutathione responses. RESULTS: After adjustment for postexercise changes in plasma volume, the data indicate a significant increase in plasma visfatin (12.5 +/- 2.0 vs. 26.6 +/- 3.9 ng/ml, p < 0.02), insulin (p < 0.05), and glucose (p < 0.002) concentrations, and homeostasis model assessment of insulin resistance (p < 0.02), immediately after the exercise session. At 45 min of recovery, all metabolic measures, with the exception of lactate, had returned to baseline levels. CONCLUSION: The elevation in plasma visfatin, together with increased plasma glucose and insulin concentrations immediately after high-intensity exercise, may sensitize tissues for postexercise glucose uptake and glycogen restoration. Our results also support a temporary and early postexercise anorexigenic metabolic state.

The effect of exercise intensity on plasma and tissue acyl ghrelin concentrations in fasted rats.

OBJECTIVE: This study was conducted to investigate the effect of exercise training and feeding status on plasma and tissue acyl ghrelin concentrations. MATERIALS AND METHODS: Thirty-two, eight-week-old male Wistar rats (185±5g) were randomly assigned to one of four groups: high intensity (HI: 34 m/min ~80-85% VO(2)max), moderate intensity (MI: 28 m/min ~70-75% VO(2)max), low intensity (LI: 20 m/min ~50-55% VO(2)max), and sedentary control (SED) groups. All experimental groups performed a 12-week exercise program consisting of treadmill running on a 0° slope for 1 h/day, 5 days/week at their respective training intensity. Twenty four hours following the last training session the animals completed a 12h fast. Rats were then killed, blood was collected and plasma separated; the fundus and soleus muscle were excised and frozen in liquid nitrogen for later analysis. Fasting levels of circulating acyl ghrelin and acyl ghrelin content in the soleus muscle and fundus, as well as glycogen in the soleus muscle were measured. Data were analyzed using one-way ANOVA. RESULTS: Results demonstrated that 12 weeks of exercise training combined with a 12h fast significantly increased plasma as well as soleus muscle concentrations of acyl ghrelin in the HI and MI groups (p<0.05) and reduced acyl ghrelin concentrations in the fundus (p<0.05). CONCLUSION: The results of the study indicate that chronic treadmill exercise training enhances fasting plasma acyl ghrelin in an intensity-dependent manner which is accompanied by a significant increase in soleus muscle and reduction in fundus acyl ghrelin levels.

Acute circuit-resistance exercise increases expression of lymphocyte agouti-related protein in young women.

Exercise-induced leukocytosis and lymphocytosis is accompanied by up-regulation and down-regulation of hundreds of genes in white blood cells (WBCs). Agouti-related protein (AgRP) is an orexigenic peptide secreted predominantly from the arcuate nucleus in the hypothalamus. AgRP affects feeding behavior and plays a role in energy and glucose homeostasis and adiposity. The purpose of the study was to determine effects of circuit resistance exercise (CRE) (9 exercises, 25 s per exercise) at different intensities on peripheral blood lymphocyte (PBL) AgRP mRNA expression and its concentrations in lymphocytes and plasma. Twenty-five young female college students were randomly divided into five groups: control, 40% 1-repetition maximum (1-RM), 60% 1-RM, 80% 1-RM and combined (40 + 60 + 80% 1-RM) loads. Peripheral blood mononuclear cells were isolated by a lymphocyte density gradient centrifugation method for AgRP mRNA expression. Lymphocyte ATP, glycogen, AgRP, growth hormone (GH), and plasma AgRP, GH and glucose concentrations were measured. CRE increased AgRP mRNA lymphocyte expression significantly (P < 0.0001) at all intensities. A higher and significant (P < 0.01) increase was found in the 60% 1-RM group when compared with the other groups. The CRE-induced lymphocyte AgRP expression was accompanied by elevations in plasma AgRP, glucose and GH levels as well as higher WBCs, lymphocytes and neutrophil counts. Lymphocyte AgRP and GH concentrations were significantly reduced (P < 0.05). Lymphocyte ATP content was unchanged and glycogen was reduced in the combined group but not in the other groups. Data indicate that AgRP mRNA is expressed in PBLs and that CRE increases its expression. Data also reveal that the expression of AgRP was accompanied with higher plasma AgRP and GH concentrations. Findings suggest that AgRP may provide an important signal in the immune environment and that the lymphocyte may be considered as an extra-hypothalamic source of plasma AgRP following exercise stress.

A single circuit-resistance exercise has no effect on plasma obestatin levels in female college students.

Obestatin is a 23 amino acid peptide recently isolated from rat stomach that is encoded by the same gene as ghrelin. Obestatin has opposite action to ghrelin on food intake and plays a role in energy balance. The purpose of the present study was to investigate the effect of a circuit-resistance exercise (9 exercises, 25s per exercise, at 40, 60, 80% of 1RM) at different intensities on plasma obestatin and growth hormone (GH). Twenty volunteer females were randomly divided into four; 40, 60, 80%, combined (40+80+80%) loads groups (COL). Blood samples were collected before and immediately following the exercise protocol. Changes in plasma obestatin levels were not significant within and between groups. Plasma GH concentrations were significantly higher in high and COL groups, respectively. The data indicate that although circuit-resistance exercise resulted in a significant change in GH levels, it had no effect on plasma obestatin levels.