Elevated skeletal muscle irisin precursor FNDC5 mRNA in obese OLETF rats

Objective. There is debate as to whether fibronectin type III domain containing 5 (FNDC5)and its protein product irisin are therapeutic targets for obesity-associated maladies. Thus,we sought to examine FNDC5 mRNA within skeletal muscle of obese/diabetic-prone OtsukaLong-Evans Tokushima Fatty (OLETF) rats versus lean/healthy Long Evans TokushimaOtsuka (LETO) rats. We hypothesized that FNDC5 expression would be greater in obese(OLETF) versus lean (LETO) animals.Materials/Methods. Triceps muscle of 30–32 week old OLETF and LETO rats were assayedfor FNDC5 and PGC1α mRNA levels. Body composition and circulating biomarkers of theOLETF and LETO rats were also correlated with skeletal muscle FNDC5 mRNA expressionpatterns in order to examine potential relationships that may exist.Results. OLETF rats exhibited twice the amount of triceps FNDC5 mRNA compared toLETO rats (p<0.01). Significant positive correlations existed between triceps muscle FNDC5mRNA expression patterns versus fat mass (r=0.70, p=0.008), as well as plasma leptin (r=0.82, p<0.001). PGC1α mRNA levels were also highly correlated with FNDC5 mRNA (r=0.85,p<0.001). In subsequent culture experiments, low and high physiological doses of leptin hadno effect on PGC1α mRNA or FNDC5 mRNA levels in C2C12 myotubes. Paradoxically,circulating irisin concentrations tended to be higher in a second cohort of LETO versusOLETF rats (p=0.085)

Editorial : The activity of satellite cells and myonuclei following 8 weeks of strength training in young men with suppressed testosterone levels

The editorial provides commentary on the following: See related article: Kvorning, T., Kadi, F., Schjerling, P., Andersen, M., Brixen, K., Suetta, C. & Madsen, K. 2014. The activity of satellite cells and myonuclei following 8 weeks of strength training in young men with suppressed testosterone levels. Acta Physiol. 201, 676-687

Calorie needs for improving body composition

There are favorable body weights/body fat percentages that allow for optimal performance in sport. Athletes attempting to reduce body weight should: 1) reduce weight in a healthy and efficient manner that can be maintained over time and 2) maximize strength-to-weight ratio. This chapter will: 1) discuss how to determine body weight for a desired body fat percentage, 2) discuss how to determine caloric consumption including the calculation of resting metabolic rate (RMR) and daily energy expenditure (DEE), 3) provide dietary suggestions to promote healthy weight loss that can be maintained over time, 4) provide athletes with tests to assess their strength-to-weight ratio, and 5) provide athletes with practical take-home messages that can be applied to training table diets

Farmer participatory evaluation of affordable microirrigation technology for vegetable production in Cambodia

Low-cost drip irrigation (LCDI) can be an affordable means of expanding irrigation into rainfed areas, thereby increasing land productivity. This study determined the performance of LCDI as evaluated by vegetable farmers in Cambodia. The study also evaluated the effects NPK fertilizer briquette compared to conventional compound fertilizer with LCDI and hand watering (HW) in two vegetable crops on yield and water use efficiency (WUE). Yield and WUE increased significantly with LCDI compared to HW on cucumber (13% and 41 %), sponge gourd (85% and 129%), eggplant (38% and 113%) and bitter gourd (121 % and 35%), but low response on long bean (5% and 27%, respectively). In general, the average yield increased by 34% and WUE increased by 76% with LCDI. Marketable yield and water use efficiency of cucumber increased (22% to 25%) with NPK briquette deep placement compared to conventional NPK fertilizer irrespective of irrigation treatments, whereas in long bean it increased only by 9% for both yield and WUE. Net increase in income due to briquette was greater by 24% and 14% on cucumber and long bean, respectively, compared to compound fertilizer. The effect of irrigation methods on man days employed for irrigation was almost six times greater in HW compared to LCDI, although no significant effect was noted on weeding and spraying operations. The average net return with LCDI was greater by 52% compared to HW and varied from 4% to 121 % between the crops. These results suggest that LCDI andNPK briquettes can significantly improve yield, WUE and profitability of vegetable crops under farmers' management conditions. Both technologies are feasible options toward increasing vegetable production and profit-ability for small-scale farming in Cambodia during the dry season when irrigation water is limited

Postexercise myogenic gene expression : are human findings lost during translation?

Muscle progenitor cell (MPC) activity is exercise responsive. Post resistance-exercise alterations in myogenic messenger RNAs (mRNAs) found by us and others may initiate these events. However, these mRNA data in the absence of microscopic MPC activity data have limited this interpretation. Alternatively, with our acute exercise data as our basis, we propose that these genes may control other hypertrophic processes in postmitotic fibers

Acute effects of ingesting a commercial thermogenic drink on changes in energy expenditure and markers of lipolysis

Background: To determine the acute effects of ingesting a thermogenic drink (Celsius, Delray Beach, FL) (TD) on changes in metabolism and lipolysis. Methods: Healthy college-aged male (23.2 ± 4.0 y, 177.2 ± 6.1 cm, 81.7 ± 11.3 kg, 22.8 ± 7.3 % fat; n = 30) and female (23.4 ± 3.1 y, 165.6 ± 8.7 cm, 62.1 ± 9.9 kg, 28.3 ± 7.4 % fat; n = 30) participants were matched according to height and weight to consume 336 ml of the TD or a noncaloric, non-caffeinated placebo (PLA). After a 12 h fast, participants reported for pre-consumption measures of height, weight, heart rate, blood pressure, resting energy expenditure (REE), respiratory exchange ratio (RER), glycerol and free-fatty acid (FFA) concentrations. REE and RER were determined at 60, 120, and 180 min post-consumption. Serum glycerol and FFA concentrations were determined at 30, 60, 120 and 180 min post-consumption. Results: When compared to PLA, TD significantly increased REE at 60, 120 and 180 min (p < 0.05). FFA concentrations were significantly greater in TD compared to PLA at 30, 60, 120 and 180 min post-consumption (p < 0.05). No between-group differences were found in RER. Conclusion: Acute TD ingestion significantly increased REE, FFA and glycerol appearance. If sustained, these changes may help to promote weight loss and improve body composition; however, these findings are currently unknown as are the general safety and efficacy of prolonged consumption

The expression of androgen-regulated genes before and after a resistance exercise bout in younger and older men

Roberts, MD, Dalbo, VJ, Hassell, SE, and Kerksick, CM. The expression of androgen-regulated genes before and after a resistance exercise bout in younger and older men. J Strength Cond Res 23(4): 1060–1067, 2009—This cross-sectional study examined aging and resistance exercise–related changes in intramuscular gene expression in younger (21.3 6 0.6 years, 84.8 6 6.0 kg, 26.6 6 2.1 kg_m22; n = 11) and older men (67.6 6 1.3 years, 88.7 6 4.8 kg, 28.6 6 1.4 kg_m22; n = 13) surrounding a single bout of resistance exercise. Participants completed 3 3 10 repetitions at 80% of their 1 repetition maximum for Smith squat, leg press, and leg extension. Muscle biopsies were obtained before and 24 hours after exercise, whereas venous blood was collected before, immediately after and 24 hours after exercise. Free testosterone levels were greater in younger participants at all time points (p , 0.05), in addition to a greater increase in the younger men immediately post exercise (p , 0.01). Preexercise human growth hormone levels between age groups were similar (p . 0.05). Human growth hormone increased immediately post exercise in both groups (p , 0.05) with a greater response occurring in the younger (p , 0.001) men. Older men expressed greater levels of androgen receptor (AR) at rest (p = 0.02). A significant correlation existed between preexercise free testosterone levels basal AR gene expression (r = 20.59, p , 0.01). These data suggest that AR expression patterns may be related to circulating free testosterone levels. Although these findings do not fully unveil the genomic effects of androgen signaling and its relationship to muscle wasting conditions, these results provide a platform for future researchers seeking to employ gene therapy to remedy muscle loss

Aging and sequential resistance exercise bout effects on housekeeping gene messenger RNA expression in human skeletal muscle.

The purpose of this study was to investigate how age and 1 week of conventional resistance exercise affects commonly used housekeeping gene (HKG) messenger RNAs (mRNAs) in skeletal muscle. Ten college-aged (18–25 years) and 10 older (60–76 years) men completed 3 lower-body resistance exercise bouts on Monday, Wednesday, and Friday, and muscle samples were obtained before bout 1 (T1), 48 hours after the first (T2) and second bouts (T3), and 24 hours after the third bout (T4). Raw Ct values indicated that b-actin and cyclophilin were more highly expressed in older vs. younger males (p < 0.01) at T1. When normalizing each HKG mRNA to the other 4 HKG mRNAs, CYC increased at T3 and glyceraldehyde-3-phosphate hydrogenase decreased at T2 (p , 0.05) in younger men. This is one of the few studies to suggest that explicit HKG mRNAs should be used depending upon age group and resistance exercise intervention

Effects of pre-exercise feeding on serum hormone concentrations and biomarkers of myostatin and ubiquitin proteasome pathway activity

Purpose: The aim of the study was to examine the acute effects of pre-exercise ingestion of protein, carbohydrate, and a non-caloric placebo on serum concentrations of insulin and cortisol, and the intramuscular gene expression of myostatin- and ubiquitin proteasome pathway (UPP)- related genes following a bout of resistance exercise. Methods: Ten untrained college-aged men participated in three resistance exercise sessions (3 x 10 at 80 % 1RM for bilateral hack squat, leg press, and leg extension) in a crossover fashion, which were randomly preceded by protein, carbohydrate, or placebo ingestion 30 min prior to training. Pre-supplement/pre-exercise, 2 h and 6 h post-exercise muscle biopsies were obtained during each session and analyzed for mRNA fold changes in myostatin (MSTN), activin IIB, follistatin-like 3 (FSTL3), SMAD specific E3 ubiquitin protein ligase 1 (SMURF1), forkhead box O3, F-box protein 32 (FBXO32), and Muscle RING-finger protein-1, with beta-actin serving as the housekeeping gene. Gene expression of all genes was analyzed using real-time PCR. Results: Acute feeding appeared to have no significant effect on myostatin or UPP biomarkers. However, resistance exercise resulted in a significant downregulation of MSTN and FBXO32 mRNA expression and a significant upregulation in FSTL3 and SMURF1 mRNA expression (p<0.05). Conclusions: An acute bout of resistance exercise results in acute post-exercise alterations in intramuscular mRNA expression of myostatin and UPP markers suggestive of skeletal muscle growth. However, carbohydrate and protein feeding surrounding resistance exercise appear to have little influence on the acute expression of these markers

Efficacy and safety of a popular thermogenic drink after 28 days of ingestion

Background: We have recently demonstrated that consuming a thermogenic drink (TD) acutely increases energy expenditure and serum markers of lipolysis in healthy, college-aged individuals. The purpose of this study was to determine if consuming TD over 28 days affects its acute thermogenic and lipolytic effects as well as body composition and clinical chemistry safety markers. Methods: Sixty healthy, males (mean ± SE; 23 ± 1 years, 177 ± 2 cm, 81.7 ± 2.1 kg, 22.8 ± 1.4% body fat; n = 30) and females (23 ± 1 years, 166 ± 2 cm, 62.1 ± 1.8 kg, 28.3 ± 1.4% body fat; n = 30) reported to the laboratory on day 0 (T1) for determination of body composition, resting energy expenditure (REE) as well as glycerol and free fatty acid (FFA) levels before and after ingesting either 336 ml of TD or a non-caloric, non-caffeinated placebo (PLA) drink. Following day 0, participants supplemented daily with 336 ml•day-1 of either TD or PLA and repeated identical testing procedures on day 28 (T2). Day 28 area under the curve (AUC) values were calculated for REE, FFA, and glycerol. Day 28 acute data and prolonged AUC comparisons between groups were analyzed using ANOVAs with repeated measures. Results: Percent body fat (p = 0.02) and fat mass (p = 0.01) decreased in the TD group compared to the PLA group after 28 days. Day 28 FFA AUC values (p = 0.048) were greater in the TD group compared to the PLA group. There was no significant difference in day 28 REE AUC values (p = 0.30) or glycerol AUC values (p = 0.21), although a significant increase in REE values in the PLA group may have confounded these findings. There were no differences between groups concerning blood and clinical safety markers. Conclusion: Within-group elevations in FFA and REE values in the TD group were still evident following a 28-day supplementation period which may contribute to the observed decrements in ¿. Further, prolonged TD supplementation did not alter the assessed clinical safety markers. Future studies should examine the synergistic and independent effects of the active ingredients in addition to effects of longer ingestion periods of TD ingestion with or without exercise at promoting and sustaining changes in body composition