bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of oleanolic acid on the regulation of water, electrolyte and the renin system (701.4)
Authors: Choi Yoon Hee , Kho Min Chul , Park Ji Hun , Cho Kyung Woo , Kang Dae Gill , Lee Ho Sub
Published: June 2021

Effect of oleanolic acid on the regulation of water, electrolyte and the renin system Yoon Hee Choi1,2, Min Chul Kho1,2, Ji Hun Park2,3, Kyung Woo Cho1,2, Dae Gill Kang1,2,3, Ho Sub Lee1,2 1Professional graduate school of Oriental Medicine, Wonkwang University, Iksan, Jeonbuk, 570‐749, Republic of Korea 2 Hanbang Body‐fluid Research Center, Wonkwang University, Shinyong‐dong, Iksan, Jeonbuk, 570‐749, Republic of Korea 3Department of Food Industry Convergence, Wonkwang University, Iksan, Jeonbuk 570‐749, Republic of Korea ABSTRACT Oleanolic acid is an active ingredient of variable plants including medicinal herbs and edible vegetables. Previously, it was shown that oral intake of oleanolic acid accentuates the atrial natriuretic peptide (ANP) system. Oleanolic acid increases cardiac ANP synthesis, plasma levels, and secretion. The purpose of the present study was to identify the effects of oleanolic acid on the regulation of fluid and electrolyte homeostasis and renal hormone balance. Experiments were performed in rats housed in metabolic cage and Oleanolic acid was administered orally everyday for 7 days. Oleanolic acid increased urinary excretion of Na+, Cl‐, and K+ . Oleanolic acid also increased urinary excretion of creatinine and clearance for creatinine. Furthermore, oleanolic acid suppressed plasma renin activity and renal renin contents. These findings suggest that oleanolic acid increases glomerular filtration rate and urinary excretion of water and electrolytes via suppression of the renin‐angiotensin system. Thus, this provides experimental evidence for beneficial effects of oleanolic acid in the cardiovascular system.

Keyworlds : Oleanolic acid;Renin‐angiotensin system;Glomerular filtration rate;Urinary; Renin activity
Role of blood pressure in chronic aldosterone‐mediated cardiac injury (701.5)
Authors: Ball Jana , Syed Maryam , Maranon Rodrigo , Reckelhoff Jane , Yanes Cardozo Licy , Iyer Rugmani , Lindsey Merry , Romero Damian
Published: June 2021

Excess aldosterone (ALDO) causes hypertension (HTN), and cardiac hypertrophy, injury and dysfunction. The role of HTN in ALDO‐mediated cardiac injury remains controversial. We aim to study the role of blood pressure (BP) in chronic ALDO‐mediated cardiac hypertrophy and fibrosis.

Eight‐week old uninephrectomized male Sprague Dawley rats (N=6/grp) were implanted with radiotelemetry probes for BP monitoring and allowed to recover for 2 wks. Animals were assigned to 4 groups: Control, ALDO (0.75 µg/h)/SALT (1.0 % NaCl + 0.3 % KCl in drinking water), ALDO/SALT+2‐AHT (240 mg/kg hydralazine and 15 mg/kg reserpine in the food) or ALDO/SALT+3‐AHT (2‐AHT plus 75 mg/kg hydrochlorothiazide). Tissue weights and cardiac fibrosis were determined at the end of the 8‐week experimental period.

All three ALDO‐treated groups reached the same BP value at the end of the 8‐wk period. However, the MAP area under the curve (AUC) was decreased in 2‐AHT (1.47 AU vs. ALDO, p<0.05; vs. 3‐AHT, p<0.05) and 3‐AHT (1.29 AU vs. ALDO, p<0.0.5) vs. ALDO (1.73 AU vs. control, p<0.05). Cardiac fibrosis positively correlated with MAP AUC (R2=0.51, p<0.05) as well as with heart, left ventricle, kidney and lung weights.

These results suggest that ALDO‐mediated cardiac hypertrophy and fibrosis is BP‐dependent without excluding that ALDO may exacerbate the HTN‐mediated cardiac injury. Stricter BP management may benefit patients with elevated ALDO levels.

Grant Funding Source: Supported by American Heart Association Grant 12SDG8980032.
REDD1 reduces the responsiveness of mTORC1 after resistance exercise and amino acid intake in skeletal muscle of elderly people (702.4)
Authors: Francaux Marc , Demeulder Bénédicte , Naslain Damien , Fortin Raphaël , Lutz Olivier , Caty Gilles
Published: June 2021

The aim of the present experiment was to highlight the difference in mTORC1 regulation between young and elderly people after exercise and amino acid intake. Eight younger (23±1 y) and 8 older (70±7 y) healthy volunteers were recruited. After an overnight fast, a first biopsy sample was taken in the vastus lateralis muscle. Then, the subjects performed a one‐leg resistance exercise consisting in 10 sets of 10 leg extensions at 70% of their 3‐RM (repetition‐maximum) previously measured. Immediately after the exercise completion, the subjects drank a beverage containing 30 g of whey protein hydrolyzate whose 2.5 g was leucine. Thirty minutes after the beverage intake, a second biopsy was taken in the exercised leg and a third one in the contralateral leg. In both groups, feeding increased the S6K1 phosphorylation and resistance exercise potentiated this effect. However, the range of these increases was about the half in elderly as compared to the young subjects confirming a reduced responsiveness of mTORC1 in elderly people. Feeding doubled the phosphorylation of PKB (Ser473) in both groups. Resistance exercise reinforced this effect in young but not in elderly people. The expression of REDD1 was systematically higher in elderly people. REDD1 was slightly and not significantly increased by exercise in young subjects whereas it was doubled in elderly suggesting that REDD1 is probably a major actor for the development of anabolic resistance during ageing. The phosphorylation state of PRAS40 (Thr246) increased after feeding but similarly in both groups. The phosphorylation state of AMPK (Thr172) was affected neither by feeding nor by exercise. All together, these results indicate that mTORC1 acts as a molecular integrator receiving positive and negative signals from its upstream regulators. The reduced responsiveness to anabolic stimuli observed in elderly people seems related to a higher REDD1 expression combined with a lower exercise‐induced activation of PKB.

Grant Funding Source: Supported by the Walloon Region (Plan Marshall – Wagralim ‐ Geramino)
Effect of early and late outpatient exercise training on muscle mass and protein kinetics in severely burned children (702.5)
Authors: Hardee Justin , Porter Craig , Sidossis Labros , Carson James , Herndon David , Suman Oscar
Published: June 2021

Severe thermal trauma is associated with profound muscle wasting and long‐term functional impairments in burn survivors. Late exercise training performed 6 to 9 months post‐injury increases leg lean mass (LM) in burned children. The impact of early outpatient exercise, initiated immediately following hospital discharge, on muscle mass has yet to be examined. Therefore, we examined the effects of early and late outpatient rehabilitative exercise training (RET) on muscle mass and protein kinetics in severely burned children. Eighty‐six children with 蠅40% total body surface area burn were randomized to 12‐weeks standard of care rehabilitation (SoC) or RET at discharge (DC) and 6 months (6M) post‐burn. DEXA was used to determine changes in LM. In a subset of patients (N=30), stable isotope infusion studies were conducted to determine muscle protein synthesis (MPS). RET increased LM compared to SoC at each time‐point (DC: 4.7% vs 17.0%; 6M: 3.0% vs 13.0%). No differences in LM were found between RET interventions. MPS decreased from DC to 6M (6.3 ± 1.4% and 3.4 ± 0.6%, respectively); however no differences were observed between SoC and RET. No changes in MPS were observed from 6 to 9 months. In addition, no differences in blood flow were found with each treatment. These results demonstrate that improvements in LM can be achieved immediately following hospital discharge and 6 months post‐burn without alterations to basal muscle protein turnover. Early and late outpatient RET are effective methods to augment muscle mass following severe burn injury.

Grant Funding Source: Supported by NIDRR grant H133A120091; NIH P50 GM060388, R01 HD049471, R01 GM056687
Daily living physical activities and muscle protein synthesis: a new and applied method with intrinsically stable isotope‐labeled milk proteins as tracer (702.8)
Authors: Reitelseder Søren , Bülow Jacob , Agergaard Jakob , Kjaer Michael , Holm Lars
Published: June 2021

Aims of this study were to evaluate effects of daily physical activities on muscle protein synthesis (MPS) and to validate a tracer protocol with intrinsically labeled milk proteins. 24 elderly (70 ± 1 y) men were recruited and randomly assigned to: inactivity (IA), daily activities (DA), or strength exercise (SE). The study protocol simulated a normal daily eating routine containing carbohydrates, fat, and [1‐13C]leucine‐labeled whey and caseinate as the primary protein source. Regular ingestion of labeled protein served to prime (whey) and maintain (caseinate) tracer enrichment for determination muscle protein fractional synthesis rates (FSR). Physical activities were monitored and venous blood and muscle biopsies collected. Total physical activity was highest in DA compared to IA and SE. Protein ingestion increased leucine and phenylalanine plasma concentrations in all groups. Plasma [1‐13C]leucine enrichment was stable throughout the 10‐h FSR measurement period. Muscle protein FSR were for IA, DA, and SE 0.065 ± 0.0050 %/h, 0.077 ± 0.0081 %/h, and 0.081 ± 0.0057 %/h, respectively (means ± SE, one‐way ANOVA P = 0.199). The prerequisites for calculating FSR was fulfilled with the tracer coming solely from oral intake of milk proteins. Under these applied settings it was not possible to detect significant differences in MPS between the inactivity, daily activities, and strength exercise interventions.

Grant Funding Source: Supported by Arla Foods Ingredients P/S and Lundbeck Foundation
ABSTRACT WITHDRAWN. (702.9)
Authors: Gunatilake Mangala , Bandara L M , Bandara H M , Yapa Maheshi , Manchanayaka Amali , Nanayakkara Udayanthi , Senevirathne P L D , Senaratne Vajira
Published: June 2021

This study was conducted to assess the cardio‐respiratory endurance according to the Body Mass Index (BMI) of male and female school children aged 13 years using 3 minute Harvard step test. This was carried out in grade 8 male children in Kannangara Vidyalaya (n=60) and grade 8 female children in Yashodara Vidyalaya, Colombo (n=60). Body weight and height were measured and BMI was calculated. Pre‐exercise and post‐exercise pulse rate, respiratory rate and blood pressure (BP) were measured. During 3 minute Harvard step exercise, average heart rate, maximum heart rate, energy expenditure and fat burn were measured using a pedometer. Mean BMI of participants was 17.70±3.42 (mean±SD) kgm‐2 for boys and 18.40±4.27 kgm‐2 for girls. Fifteen percent, 1.67% and 18.33% of the boys were overweight, obese and underweight respectively whereas in girls those percentages were 13.3%, 5% and 25% were respectively. BMI had significant correlation with pre‐exercise systolic blood pressure in boys (109.38±19.54mmHg) (rp=0.308,p=0.017) and girls (109.18±15.59mmHg) (rp=0.659,p=0.000) and also with pre‐exercise diastolic blood pressure in boys (71.40±13.07mmHg) (rp=0.342,p=0.008) and girls (69.57±10.44mmHg) (rp=0.690,p=0.000). Ninety percent of boys and 67.7% of girls completed 3 minutes Harvard step test. BMI also had positive significant correlations with energy expenditure and fat burning during exercise in both genders. Overweight and underweight were prevalent among the studied adolescents and obesity was more prevalent among girls. Correlation of BMI with blood pressures may predict the risk of pre‐hypertension and hypertension in overweight and obese adolescents. As the reduction in the fat content in adolescents with high BMI is at a higher rate during physical exercise, we suggest that introducing regular exercise programmes at school level would help in the prevention of non‐communicable diseases in the future generations.
Central actions of hydrogen sulfide (703.1)
Authors: Yosten Gina , Samson Willis
Published: June 2021

Hydrogen sulfide (H2S) is a novel gaseous signaling molecule that has been shown to exert multiple beneficial effects in vivo, including anti‐inflammatory actions and protective effects in the gastrointestinal tract. HS converting enzymes are produced in the central nervous system, and thus may exert important actions in brain. We therefore tested the ability of HS to modulate mean arterial pressure, fluid intake, and stress hormone secretion in adult, male rats, via intracerebroventricular (icv) injection H2S donors (sodium hydrosulfide hydrate). Central administration of H2S donors led to rapid, transient, dose‐related increases in mean arterial pressure in conscious, freely moving male rats, but did not alter water or saline intakes. Furthermore, injection of H2S donors led to an increase in plasma corticosterone levels, but not plasma prolactin levels, in non‐stressed animals. From these data, we conclude that H2S may act as an important signaling molecule in brain, although elucidation of the physiological relevance of this gaseous messenger requires further evaluation.
The effect of sex on IL‐6 regulation of cancer cachexia progression in the Apc min/+ mouse (704.2)
Authors: Hetzler Kimbell , Sato Shuichi , Narsale Aditi , Puppa Melissa , Carson James
Published: June 2021

Cachexia is a condition that arises secondary to many chronic diseases and accounts for more than 20% of cancer‐related deaths. Cachexia occurs in both sexes, but research into its etiology and progression has been almost exclusively in the male. Our lab has previously shown that body weight loss in the male Apc min/+ mouse is closely associated with plasma IL‐6 and triglyceride levels as well as tumor burden. The purpose of the present study was to determine if sex alters IL‐6 regulation of cachexia progression in Apc min/+ mice. 24 female Apc min/+ mice were monitored during the development of cachexia until sacrifice at 20 weeks of age. Plasma IL‐6 and triglycerides as well as intestinal polyps were quantified. Body weight loss from peak ranged from 0% to 21%, with 30% of mice becoming severely cachectic. Plasma IL‐6 levels varied from 4.4‐39.7 pg/ml, which is comparable to the male. Similar to the male, body weight loss was correlated with tumor number (p=0.01). Unlike the male, there was neither a relationship between body weight loss and plasma IL‐6 or triglyceride levels; nor between tumor number and plasma IL‐6 level. Interestingly, muscle mass loss was inversely correlated with plasma IL‐6 level (p=0.03), which is contrary to the male. We present evidence that sex can affect the relationship between muscle mass loss, cachexia development, and plasma IL‐6 in the Apc min/+ mouse, which may impact therapeutics for cachexia.
The effect of metabolic acidosis on maximal force production and muscle recruitment during repeated, submaximal calf contractions to task failure (705.11)
Authors: Siegler Jason , Poulsen Mathias , Nielsen Niels‐Peter , Kennedy David , Marshall Paul , Green Simon
Published: June 2021

The purpose of this investigation was to assess the influence of metabolic acidosis on maximal force (MVC) production and muscle recruitment during repeated, submaximal calf contractions to task failure. Eight males completed three experimental trials (0.3g·kg‐1 sodium bicarbonate (ALK); 0.2g·kg‐1 ammonia chloride (ACD); or 0.3g·kg‐1 calcium carbonate (PLA)), each consisting of submaximal calf contractions at 55% of MVC to task failure. At one minute intervals of the task subjects performed an MVC, where stimulation of the tibial nerve (150% of Mmax) was performed during and immediately post MVC. Time to task failure was not different between conditions (ACD: 531.3 ± 166.0s, PLA: 591.8 ± 162.6s, ALK: 595.6 ± 149.6s; p = 0.31). Maximal force (Fmax) immediately prior to exercise was not significantly different between ACD (1,389 ± 210 N), ALK (1,413 ± 207 N) and PLA (1,358 ± 191 N), and declined at similar rates throughout the task. Although no difference was apparent between ACD, PLA and ALK (p = 0.30), in all trials a significant decline in peripheral twitch amplitude from the first MVC (150.5 ± 9.2 N) to the 6th MVC (119.0 ± 7.8 N) was evident (mean decline of 31.4 ± 5.4 N (95% CI = ‐48.4 to ‐14.5 N); p < 0.01). No further decline was evident from the 6th MVC to task failure (mean decline of 3.9 ± 4.2 N; p = 1.0). Fatigue as assessed via MVC and twitch contractile properties is not affected by variation in acid‐base status.
Effect of prior exercise on postprandial lipemia: an updated quantitative review (705.14)
Authors: Freese Eric , Gist Nicholas , Cureton Kirk
Published: June 2021

Reducing postprandial triglycerides (TG) can lower the risk for cardiovascular disease. The purpose of this study was to perform a meta‐analytic review of the literature to estimate the effect of prior exercise on postprandial lipemia. A total of 121 effects were found from 76 studies for the total TG response and 70 effects from 44 studies for the incremental area under the curve (iAUC) TG response. The weighted mean effect was moderate for the total TG response, Cohen’s d = ‐0.60 (P < 0.0001), and for the iAUC response, Cohen’s d = ‐0.59 (P < 0.0001). Moderator analysis revealed women exhibited a larger reduction (P < .01) in the total TG response following exercise (d = ‐0.96) than men (d = ‐0.57); high‐intensity interval training induced a larger reduction (P < .05) in the iAUC response (d = ‐1.49) than aerobic (d = ‐0.58) or resistance (d = ‐0.13) exercise; and, participants maintaining an energy deficit following exercise exhibited a greater reduction in the iAUC response (d = ‐0.67) compared to participants in energy balance (d = ‐0.28). This quantitative review found that prior acute exercise causes a moderate‐to‐large reduction in postprandial lipemia, with the magnitude of effect influenced by sex, type of exercise and maintenance of an energy deficit following exercise.
Salivary mtDNA copy number: index of aerobic efficiency? (705.6)
Authors: Chen Yang , Hill Helene , Klein Jacquelyn , Ndirangu Duncan , Falvo Michael
Published: June 2021

Objective: Mitochondrial DNA (mtDNA) is central to oxidative phosphorylation and energy production. mtDNA copy number (mtDNAcn) may serve as an index of mitochondrial density, but has not been well studied in saliva. Our goal was to determine whether salivary mtDNAcn is related to measures of aerobic efficiency and fitness.

Methods: 15 men (32±8.3 yrs) volunteered for this study and performed exercise challenge testing, completed physical activity questionnaires, and provided a saliva sample for mtDNAcn analysis. Relative mtDNAcn was determined by real‐time PCR in saliva DNA from individuals. Subjects were assigned to HIGH and LOW aerobic efficiency groups based on the ratio of ventilation and oxygen consumption (Ve/VO2). Variables of interest were mtDNAcn, maximum oxygen consumption (VO2/kg), respiratory exchange ratio (RER) and physical activity scores.

Results: Ve/VO2 was significantly correlated with relative mtDNAcn (R2=0.32, p=0.03). HIGH aerobic efficiency group had significantly higher mtDNAcn (t=2.34, p=0.03), VO2/kg (t=3.25, p<0.01), physical activity scores (t=2.24, p=0.04) and a lower RER (t=2.50, p=0.03) than LOW aerobic efficiency group.

Conclusions: mtDNAcn is related to aerobic efficiency such that individuals with HIGH aerobic efficiency have significantly greater mtDNAcn. Future studies may consider salivary mtDNAcn in the evaluation of exercise tolerance and efficiency.

Grant Funding Source: VA Grants 1I21RX001079‐01 and 1I21CX000797‐01
Exercise causes repositioning of the ‐1 nucleosome within the PGC1α promoter in association with altered gene expression in skeletal muscle (705.7)
Authors: Henagan Tara , Covington Jeffrey , Stewart Laura , Galgani Jose , Ravussin Eric , Bajpeyi Sudip
Published: June 2021

Skeletal muscle PGC1α expression is epigenetically regulated by promoter methylation. Methylation status at the ‐260 nucleotide (nt) within the promoter plays an important regulatory role in determining PGC1α expression and consequently mitochondrial number and function and insulin sensitivity. Here we identified ‐1 nucleosome (‐1N) position within the PGC1α promoter in muscle from sedentary, lean men (n=18, aged 24±1 yrs, BMI 23.8±0.4) before and immediately after an acute bout of exercise (50% VO2max, ~650 kcal). Nucleosome position was measured by scanning PCR. At baseline, the ‐1N position spanned the promoter region from nt ‐350 to ‐190, covering the regulatory ‐260 nt methylation site. Following the exercise bout, the ‐1N was repositioned upstream, spanning the region from nt ‐500 to ‐300. PGC1α expression was significantly increased (1.05±.08 to 1.29±0.11 fold change, P = 0.02) following the exercise bout. Increased PGC1α expression was correlated with the upstream ‐1N position following the exercise bout (R2 = 0.43, P = 0.03). We provide evidence that an acute bout of exercise repositions the ‐1N in the PGC1α promoter upstream of the regulatory ‐260 nt methylation site, which may prevent DNA methyltransferase recruitment and methylation thus causing increased gene expression.

Grant Funding Source: Support by NIH NIDDK 5T32‐DK064584‐09 (TMH)
Effects of aerobic interval and moderate continuous training on endogenous thrombin generation modulated by hypoxic exercise in sedentary men (706.10)
Authors: Ho Ching‐Wen , Wang Jong‐Shyan
Published: June 2021

This study investigated how aerobic interval (AIT) and moderate continuous training (MCT) influence endogenous thrombin generation (TG) and coagulation cascade induced by hypoxic exercise in sedentary men. Twenty‐four sedentary males were randomized to perform AIT (3‐minute intervals at 40% and 80% VO2 peak, n=12) or MCT (sustained 60% VO2 peak, n=12) for 30 minutes/day, 5 days/week for 6 weeks. Dynamic TG and coagulation factors in plasma were measured by calibrated, automatic thrombinography and coagulation analyzer, respectively. The results showed that, before exercise training, the 60%VO2max exercise under 12%O2 increased endogenous thrombin potential (ETP) and TG rate, which were accompanied by shortened activated partial thromboplastin time (aPTT) and reduced coagulation factor VIII (FVIII) level in plasma. However, both AIT and MCT diminished the enhancements of ETP and TG rate by the 12%O2 exercise, and simultaneously lengthened aPTT and lowered FVIII level in plasma. Accordingly, we conclude that either AIT or MCT effectively attenuates hypoxic exercise‐induced dynamic TG by suppressing intrinsic coagulation activation in sedentary men.
Aerobic exercise training decreased oxidative stress in aged females rats after ovarian hormones deprivation (706.11)
Authors: Dias Danielle , Bernardes Nathalia , Brito Janaina , Conti Filipe , Irigoyen Maria Cláudia , De Angelis Kátia
Published: June 2021

The objective was to investigate the effects of aerobic exercise training on parameters of oxidative stress profile in aged females rats after ovarian hormones deprivation. Female aged ovariectomized Wistar rats (~18 wks of age) were divided into 2 groups (n=8/each) sedentary (OVXs) and trained group (OVXt). The exercise training was performed on a treadmill (8wks, 60% VO2 max). Oxidative profile was evaluated by membranes lipoperoxidation by thiobarbituric acid reactive substances (TBA), chemiluminescence (CL) and antioxidants enzymes: catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) in cardiac, muscle and renal tissues. The redox state was performed in the heart. The TBA and CL were reduced in muscle and in the cardiac tissue (101% and 68%; 46% and 93%, respectively) in OVXt group in relation to OVXs group. The levels of CAT, SOD were higher in OVXt than OVXs group in renal tissue. GPx was higher in cardiac, renal and muscle tissues in OVXt group in relation to OVXs group. The redox state was higher in OVXt (5.4±0.34 mmol/g tissue) than OVXs (2.94±0.52 mmol/g tissue) group. These results suggest a beneficial role of exercise training in oxidative stress profile in different tissues in aged rats after ovarian hormone deprivation.
Impact of aerobic and resistance exercise training on body composition and basic physical fitness in obese adolescent (706.15)
Authors: Jin Haeng Mi , Yang Eun Hye
Published: June 2021

The purpose of this study was to examine the changes of body composition and basic physical fitness after aerobic and resistance exercise training in obese adolescent. Twenty obese adolescent (mean age: 15 years) were recruited and they were randomly assigned into exercise training group (ETG, n=10) and control group (CG, n=10). Body composition, including body weight (BW), body mass index (BMI), body fat percentage (%BF) and waist circumference (WC), and basic physical fitness parameters such as agility, muscular strength, muscular endurance, flexibility and power were measured before and after ET. The ET was performed during 16weeks (80 minutes a day, 4 days a week). ETG presented decreases in BW, BMI, %BF and WC after 16 weeks of ET while no changes were observed in CG. ETG presented increased grip strength (indicator of muscular strength, p<0.05) and length of both chair sit & reach (indicator of flexibility, p<0.05) and standing broad & long jump (indicator of power, p<0.01) after ET but there were no changes in side step and sit up (indicators of agility and muscular endurance). Compared to ETG, CG presented no increases in basic physical fitness parameters after study. In conclusion, aerobic and resistance exercise training was beneficial to improve body composition and enhance basic physical fitness including muscular strength, flexibility and power in obese adolescent.
Impact of aerobic exercise intensity on body weight and adipokine concentrations in middle‐aged obese women (706.2)
Authors: Jin Haeng Mi , Eom Joo Hwan
Published: June 2021

The purpose of this study was to investigate the effect of different aerobic exercise (AE) intensity on changes of body weight (BW) and adipokine concentrations in middle‐aged obese women. Sixteen obese women (%body fat 蠅30%, age range: 40‐59 years) were randomly assigned into high‐intensity (HI) AE (VO2max 50%, n=8) or moderate‐intensity (MI) AE (VO2max 80%, n=8). Subjects in both groups performed AE until they burn 400 calories at a time during 8 weeks (5 times/week). BW and adipokines, including leptin and adiponectin, were measured before and after AE. Both groups lost BW and presented decreased leptin concentration after AE but no statistical differences were observed between groups. MIAE presented slightly increased adiponectin concentration (0.03±7.34μg/mL) while HIAE presented decreased adiponectin concentration (‐6.91±6.94μg/mL) after AE, however there was no statistical difference between groups as well. In both groups, change of BW was positively correlated with change of leptin concentration (r=0.830, p<0.001). In conclusion, AE intensity does not influence changes of BW and adipokine concentrations in middle‐aged obese women but decreased BW was associated with leptin change.
The role of skeletal myofiber VEGF in the cerebral neurogenic response to exercise (706.21)
Authors: Rich Benjamin , Scadeng Miriam , Wagner Peter , Breen Ellen
Published: June 2021

Exercise induces cerebral neurogenesis. This phenomenon has been suggested to require peripheral vascular endothelial growth factor (VEGF). We hypothesized that skeletal myofiber VEGF may regulate blood flow and neurogenesis in the hippocampus. This was tested in adult skeletal myofiber specific VEGF gene ablated mice (skmVEGF‐/‐) provided running wheels for 14 days. We measured exercise capacity, neurogenesis (BrDU+/NeuN+ cells) and post‐training cerebral blood flow (CBF) detected by fMRI. Voluntary distances ran each day did not differ between groups. There was a trend for higher BrDU+/NeuN+ cells/0.1 mm2 in WT mice (WT, 4.8+2.0, skmVEGF‐/‐ 1.8+0.6; p=0.08). CBF in mice breathing 21% or 10% O2 did not differ between groups. Endurance was increased in WT compared to skmVEGF‐/‐ mice post‐training (Pre‐training; WT 80+15 min., skmVEGF‐/‐, 27+5 min., Post‐training; WT 107+21 min., skmVEGF‐/‐, 42+8 min., p<0.05). Speed improved in WT mice with training (Pre‐training; WT 61+2 cm/s, skmVEGF‐/‐, 51+3 cm/s, Post‐training; WT 69+3 cm/s, skmVEGF‐/‐, 61+4 cm/s, p<0.05). These data suggest that myofiber VEGF, independent of CBF, may regulate exercise‐induced neurogenesis.

Grant Funding Source: American Heart Association
Impact of biorhythms to athletic performance of kickboxers high skills (706.23)
Authors: Daulenbaev M. , Syzdykova S. , Slivkina N. , Kudashov E.
Published: June 2021

The purpose is to determine the effect of multi‐day biorhythms to the success of the performance at the kickboxing high qualifications competition. The analysis of the data based on performances in the competition professional kickboxer K. Ustinov (Russia) in 2009‐2010. According to the tables for sports performances in the competitions, multi‐day biorhythms were determined according to the computer program at fights on the “ Biorhythm Windows” BIOW, version v 3.20). Results. We can conclude that won fights by a boxer of high qualifications according to two years of follow‐up was 42.8% in fights by decision, 14.3%‐ knockout, and 56.1% by technical knockout.

The influence of multi‐rhythms reflected in the results of the fight match, and it was positive with intellectual rhythm and negative with the physical biorhythms that should be included in training and competitive periods of sportsmen training.

Analysis of the data for 2 years fighting performances of boxer Alexei Ustinov allowed to conclude the following: 1.Multi‐day biorhythms have an impact to the outcome of the match and it the biggest with intelligent (r=0,845) and natural biorhythms (r=0,665; r=0,68) with a technical knockouts, and negative (by winning fights by decision) with the physical biorhythms (r=‐0,822).
Actual issues of sports training system (706.24)
Authors: Kudashova L. , Syzdykova S. , Dyusupova R. , Lozbina A.
Published: June 2021

Further growth in athletic performance should be associated with the revision of the existing system of training and to search the most significant factors determining and limiting athletic performance. The aim of this work is to give scientific and methodological rationale role of functional training athletes in the training process. Methods: analysis of scientific literature, teaching observation, research methods of physical performance volleyball, electrocardiography. The results of the study. Our studies on highly skilled volleyball players showed that the dependences are quite high between the studied parameters regulating heart rhythm, physical performance under different pulse modes 130,150,170 beats per minute, maximum oxygen consumption, alaktat and glycolytic reserves of volleyball players in the preparatory period.

It is revealed that aerobic reserves are closely dependent on the performance of regulation of heart rate , stress index , physical performance at the pulse of 130 and 170 beats per minute. It is proved that the physical working capacity at the pulse of 170 beats per minute depends on the level of the MOC and the stress index of cardiac activity, and glycolytic reserves had a close relationship with the level of the heart rate , sympathetic regulation of the body's capacity for work , and when the pulse 150 beats per minute.
Effects of swimming training and estrogen therapy on the vascular reactivity of hypertensive ovariectomized rats: role of renin angiotensin system (706.7)
Authors: Abreu Glaucia , Bissoli Nazare , Carvalho Ana Ligia , Gonçalves Erick , Endlich Patrick
Published: June 2021

Effects of swimming training and estrogen therapy on the vascular reactivity of hypertensive ovariectomized rats: role of renin angiotensin system Glaucia R Abreu, Nazare S Bissoli, Ana Ligia R Carvalho, Erick Roberto C Gonçalves, Patrick W Endlich: Health Science Center, Federal University of Espirito Santo, Brazil Several studies showed up regulation of Renin Angiotensin System (RAS) after menopause and the ability of physical training in reduces cardiovascular risk factors. The aim of this study was to analyze the effects of swimming training (eight weeks) and estrogen therapy (5 mg of 17β‐Estradiol, s.c.) on vascular reactivity and the expression of RAS of aorta rings in ovariectomized spontaneously hypertensive rats (SHR). The groups were divided: Sham (S), Ovariectomized (OVX), ovariectomized (OTE2), ovariectomized+swimming ON) and ovariectomized treated with E2 plus swimming (OE2+N). The systolic blood pressure was measured after the animals were sacrificed and blood was collected to measure Angiotensin II plasma levels by radioimmunoassay. Aorta reactivity we evaluated in response to Ang II and Angiotensin‐(1‐7) and RAS proteins expression were made by Western Blotting method. Both exercise and E2 increased Ang II plasma levels. However, the systolic blood pressure was attenuated by treatments. The OVX group showed increase in the constrictor response to Ang II and decrease dilatator response to Ang (1‐7), that was reverted by swimming training or E2 therapy associated to swimming. Moreover, ON and OE2+N groups showed increase in the AT2 and Mas receptor expression. On the other hand, the ON showed increase in the superoxide dismutase (SOD) anti‐oxidant enzyme and only the groups treated with E2 showed increase on eNOS expression. Then both swimming training and E2 treatment may play a non‐additive, role in the cardioprotection and the chronic physical exercise can be a feasible alternative in relation to estrogen therapy in post‐menopausal women.

Grant Funding Source: Capes;CNPq
Catecholamine responses to central hypovolemia induced by lower body negative pressure and blood loss in humans (707.2)
Authors: Johnson Blair , van Helmond Noud , Curry Timothy , Convertino Victor , Joyner Michael
Published: June 2021

We tested the hypothesis that the catecholamine response would be similar during lower body negative pressure (LBNP) vs. blood loss (BL). Twelve men underwent randomized LBNP and BL protocols on the same day. LBNP consisted of 5‐minute stages at 0, ‐15, ‐30, and ‐45 mmHg of pressure. The BL protocol included 5 minutes at baseline and then after three stages of 333 ml of whole blood draws (1000 ml total) which were stored for reinfusion. Central venous pressure (CVP) was recorded during each protocol. Blood samples were collected at baseline and at the end of the last stage of each protocol. CVP was greater in LBNP vs. BL at baseline (7.3 ± 0.6 vs. 6.1 ± 0.6 mmHg; P < 0.01) and was lower during LBNP vs. BL (‐0.2 ± 0.6 vs. 1.8 ± 0.8 mmHg; P < 0.01). The increase in epinephrine (EPI) during LBNP (53 ± 7 vs.144 ± 30 pg/ml) and BL (49 ± 7 vs. 103 ± 19 pg/ml; P < 0.01) was similar (P = 0.16). An increase in norepinephrine (NE) during LBNP (148 ± 20 vs. 354 ± 44 pg/ml; P < 0.01) was greater (P < 0.01) than the trend to increase during BL (155 ± 22 vs. 211 ± 29 pg/ml; P = 0.09). Individual slopes of catecholamines vs. CVP were calculated to determine if the responses had similar trajectories between the two protocols. The EPI vs. CVP slope was steeper in LBNP vs. BL (‐13.5 ± 4.6 vs. ‐0.6 ± 0.1 pg/ml/mmHg; P < 0.01). The NE vs. CVP slope was steeper in LBNP vs. BL (‐27.8 ± 5.6 vs. ‐8.7 ± 5.9 pg/ml/mmHg; P = 0.01). LBNP to ‐45 mmHg appears to be a greater sympathetic stressor than 1000 ml of BL.

Grant Funding Source: Supported by US Army MRMC Combat Casualty Care Research Program Grant # W81XWH‐11‐1‐0823
Hemorrhagic shock resuscitation using a polymerized hemoglobin oxygen carrier versus whole blood (707.5)
Authors: Ortiz Daniel , Cabrales Pedro
Published: June 2021

The development of an efficient alternative to blood transfusion to treat severe hemorrhage is of great public health importance, especially in far forward scenarios where blood is not available. Hemoglobin (Hb) based oxygen (O2) carriers (HBOCs) have been developed to address this need. Hemopure® (HBOC‐201, bovine Hb glutamer‐250, OPK Biotech,Cambridge, MA, USA), a polymerized Hb based HBOC, has been approved for clinical use in South Africa and Russia. At the time of its approval, however, few studies aimed to understand Hemopure’s function, administration, and adverse effects compared to blood. We have used intravital microscopy to study the microcirculation hemodynamics (arteriolar and venular diameters and blood flow and functional capillary density (FCD)) and oxygenation outcomes of Hemopure® administration at different Hb concentrations _4, 8, and 12 gHb/dL_ compared to fresh blood transfusion for resuscitation from hemorrhagic shock. Experiments are performed in unanesthetized hamsters instrumented with a skinfold window chamber, subjected to hemorrhage (50% of the blood volume, BV), followed by 1 hour hypovolemic shock and fluid resuscitation (50% of the shed volume). Our results show that fluid resuscitation with Hemopure® or blood restored systemic and microvascular parameters. O2 delivery in the microcirculation was directly correlated with Hemopure® concentration, however,increased vasoconstriction was as well. FCD reflected the balance between enhanced O2 transport and reduced blood flow: 12 gHb/dL of Hemopure® and blood had lower FCD compared to the lower concentrations of Hemopure® (p<0.05). The balance between O2 transport and tissue perfusion can provide superior resuscitation from hemorrhagic shock compared to blood transfusion by using a low Hb concentration of HBOCs relative to blood.

Grant Funding Source: Supported by: NIH R01 HL52684, R01 HL064395 and R01 HL062318 and ARMY: W81XWH‐11‐2‐0012
Augmented carotid body chemosensitivity during hyperthermia is blunted with low‐dose dopamine (709.3)
Authors: Thomas Kathryn , Johnson Blair , Schlader Zachary , Amaefuna Steve , Crandall Craig , Joyner Michael
Published: June 2021

We tested the hypothesis that ventilation (VE) and the hypoxic ventilatory response (HVR) during hyperthermia would be attenuated when carotid body chemosensitivity is blunted by an IV infusion of dopamine (2 µg/kg/min) vs. IV saline. We studied 9 subjects (1 woman, 32 ± 2 years, 25.7 ± 0.7 kg/m2) over two randomized dopamine and saline study visits. We measured VE and HVR (3 minutes at: room air, 16% O2, and 10% O2) at baseline and during normothermia (NORMInf) and hyperthermia (HYPInf) (core temperature 1.2‐1.5°C above baseline) infusion conditions. VE increased during HYPInf vs. NORMInf during dopamine (8.2 ± 0.3 vs. 10.2 ± 1.1 L/min; P = 0.04) and saline (8.9 ± 0.3 vs. 9.7 ± 0.5 L/min; P = 0.04) with no difference between conditions (P = 0.95). HVR during saline increased from baseline (0.30 ± 0.1 L/min/%SaO2; P < 0.01) and NORMInf (0.42 ± 0.1 L/min/%SaO2; P = 0.02) to HYPInf (0.77 ± 0.2 L/min/%SaO2). HVR did not change throughout the dopmaine visit (baseline = 0.38 ± 0.1; NORMInf = 0.27 ± 0.1; HYPInf 0.42 ± 0.1 L/min/%SaO2; P > 0.46). Dopamine HVR was lower than saline during HYPInf (P < 0.01). These data indicate that carotid body chemosensitivity to hypoxia is augmented during hyperthermia and that low dose dopamine was unable to lower normoxic VE during hyperthermia.

Grant Funding Source: Supported by NIH R01DK090541 and RO1HL61388
Carotid body denervation prevents pulmonary edema, attenuates left ventricular remodeling and restores normal autonomic balance in chronic heart failure after myocardial infarction (709.5)
Authors: Saku Keita , Kishi Takuya , Fujii Kana , Nishizaki Akiko , Takehara Takako , Akashi Takuya , Kakino Takamori , Ikeda Masataka , Oga Yasuhiro , Arimura Takahiro , Shinoda Masako , Ide Tomomi , Sunagawa Kenji
Published: June 2021

Background: The hypersensitive peripheral chemoreflex induces sympathoexcitation and vagolysis and is known to associate with the poor prognosis of chronic heart failure (CHF). We hypothesized that denervation of carotid body (CBD) improves CHF and restore the normal autonomic balance in a rat model of myocardial infarction (MI)‐induced CHF. Methods: We created MI‐induced CHF in rats. Surviving rats at 4 weeks after MI were randomized into CBD (n=10) and sham‐operated (Sham; n=10) group. To establish CBD, we removed the tissues around the carotid bifurcation. Two months after CBD, we evaluated physiological and histological findings. Results: CBD significantly reduced biventricular weight (2.9±0.1 vs. 3.3±0.1 g/kg, p<0.05), lung weight (5.6±0.4 vs. 8.1±0.3 g/kg, p<0.05), LV end‐diastolic pressure (13.7±3.2 vs. 28.3±3.1 mmHg, p<0.05) and heart rate (HR) (336±6 vs. 364±5 bpm, p<0.05). Power spectral analysis of HR demonstrated the increased power in the high frequency range (29.0±8.2 vs. 81.0±9.5 n.u., p<0.05) indicating the restoration of vagal tone. Histologocal analysis showed CBD decrease fibrosis and the invasion of macrophages in myocardium. Conclusion: CBD prevents pulmonary edema, attenuates LV remodeling and restores normal autonomic balance in CHF rats. CBD can be a novel neuro‐modulating therapy for CHF patients.
Genetic analysis of exercise capacity and training responses in 129S1/SvImJ and NZW/LacJ mice (711.12)
Authors: Massett Michael , Avila Joshua , Kim Seung
Published: June 2021

Genetic factors determining exercise capacity and the magnitude of the response to exercise training are poorly understood. The aim of this study was to identify quantitative trait loci (QTL) associated with exercise training in mice. Based on marked differences in training responses in inbred NZW (‐0.65 ± 1.73 min) and 129S1 (4.31 ± 2.79 min) mice, a reciprocal intercross breeding scheme was used to generate 288 F2 mice. All F2 mice completed an exercise performance test before and after a 4‐week treadmill running program, resulting in an increase in exercise capacity of 1.54 ± 3.69 min (range = ‐10 to +12 min). Genome‐wide linkage scans were performed for pre‐training, post‐training, and change in run time. For pre‐training exercise time, suggestive QTL were identified on Chromosomes 5 (57.4 cM, 2.5 LOD) and 6 (39.8 cM, 2.8 LOD). Suggestive QTL for post‐training exercise capacity were identified on Chrs 1 (52.0 cM, 2.2 LOD) and 5 (43.4 cM, 3.3 LOD). A suggestive QTL for the change in run time was identified on Chr 6 (37.8 cM, 2.9 LOD). To identify shared QTL, this data set was combined with data from a cross between B6 and FVB strains. In the combined cross analysis, a significant novel QTL for pre‐training exercise time was identified on Chr 12 (54.0 cM, 3.45 LOD) and a suggestive QTL for post‐training exercise capacity on Chr 8 (23.9 cM, 2.92 LOD). These data indicate that one or more QTL determine exercise capacity and training responses in mice.

Grant Funding Source: Supported by NIH HL‐085918
microRNA‐21 expression analysis in mice (711.6)
Authors: Syed Maryam , Ball Jana , Miguel‐Hidalgo Jose , Romero Damian
Published: June 2021

MicroRNAs (miRNAs) are endogenous, non‐coding RNAs that downregulate the expression levels of specific proteins by translational repression or mRNA degradation. miR‐21 has been implicated in cancer, development, immunity and cardiovascular diseases. However, miR‐21 expression at the cellular level in normal tissues remains controversial.

The aim of the study was to analyze miR‐21 expression at the cellular level in normal mouse tissues using a novel transgenic reporter mouse that expresses β‐galactosidase (LacZ) under the endogenous miR‐21 promoter. Mir21tm1Mtm/Mmjax mice were crossed with CAG‐Cre mice to delete the neomycin/miR‐21 cassette and generate lacZ‐KO‐Mir21tm1Mtm/Mmjax mice. Tissues from 10‐week old male lacZ‐KO‐Mir21tm1Mtm/Mmjax mice were embedded in OCT, cryosectioned and LacZ detected by histochemistry.

MiR‐21 was highly expressed in the cardiac fibroblasts and tunica media of coronary arteries, periportal hepatocytes, kidney collecting ducts, respiratory epithelium of the bronchus in the lung, and testis seminiferous tubules. In the CNS, miR‐21 was highly expressed in the brain white matter, corpus callosum, anterior commissure, striatum, posterior thalamus and medulla oblongata.

Although miR‐21 is expressed in multiple tissues in the adult mice, its expression at the cellular level is highly restricted, suggesting still unexplored roles for miR‐21 in health and disease.

Grant Funding Source: Supported by American Heart Association Grant 12SDG8980032.
ACTN3 genotype predicts metabolic, anthropometric and cardiovascular phenotypes in a young, healthy population (711.8)
Authors: Deschamps Chelsea , Connors Kimberly , Shearer Jane , Gnatiuk Elizabeth , Hoffman Eric , Hittel Dustin
Published: June 2021

Exercise‐related polymorphisms have played an important role in shaping human evolution. One such polymorphism, ACTN3 R577X, is overrepresented in endurance athletes and centenarians suggesting an association with favorable metabolic health. As such, we examined the influence of ACTN3 genotype on health‐related phenotypes in young subjects (age 18‐35) from the Assessing Inherent Markers for Metabolic syndrome in the Young (AIMMY) study (n=188). Cardiovascular, anthropometric, metabolic and body composition characteristics were assessed. ACTN3 genotype was associated with BMI in a sex specific manner, with null (XX) females having higher scores, while male positive (RR/RX) allele carriers had greater scores compared to XX males (p<0.05). Similarly, body fat percentage and waist circumference measurements were higher in females of the XX genotype compared to RR/RX allele carriers (p<0.05). In males, body circumferences and waist:hip ratio were higher in RR/RX allele carriers compared to XX individuals. Interestingly, Male RR/RX allele carriers had higher blood glucose and diastolic blood pressure than XX males. It was also found that female RR/RX carriers had higher VO2 peak scores than XX females (p<0.05). Metabolic and cardiovascular associations with ACTN3 genotype may offer novel insight into predicted athletic performance and disease risk.
Rapid nicotine‐evoked neurotransmitter respecification in the brainstem of the developing chick embryo (712.10)
Authors: Vincen‐Brown Michael , Still Katie , Quick Forrest , Pilarski Jason
Published: June 2021

The developing brainstem generates periodic spontaneous neural activity (SNA). SNA is thought to be crucial for the maturation of motor neurons and associated neural networks. Beginning around embryonic day five (E5), SNA is driven by cholinergic nicotinic neurotransmission (NT) with only minor modulatory inputs from ƴ‐aminobutyric acid GABA/glycinergic NT. Here we tested the effects of embryonic nicotine exposure on the neurogenesis of SNA in brainstem regions that later support homeostatic functions such as breathing. We hypothesized that brain stem motor circuits will compensate for nicotine blockade of nicotine acetylcholine receptors (nAChR) to maintain SNA by rapidly shifting to GABA/glycinergic NT. To test our hypothesis we used electrical physiological recordings and pharmacology before and after chronic nicotine exposure to probe for nicotine evoked plasticity of brain stem derived SNA in chick embryos on E5‐E5.5. Results show that nicotine abolished SNA at millimolar concentrations similar to those detected in human plasma following a single cigarette. However SNA recovered quickly (蠄 4 h) while still in the presence of nicotine suggesting that compensatory neurotransmitter(s) was driving SNA activity. Indeed, results show that GABA/glycinergic NT is required to drive SNA in the absence of nAChR availability demonstrating a form of activity dependent neural plasticity. In summary, our results show that the developing brain stem can rapidly adapt to perturbations of previously well‐defined CNS neurotransmitters to maintain SNA, and suggests that neurotransmitter phenotypic plasticity is a critical feature of the embryonic brainstem that may function to maintain the integrity of homeostatic oscillatory network functions in vivo.