Effects of short-term ingestion of Russian Tarragon prior to creatine monohydrate supplementation on whole body and muscle creatine retention and anaerobic sprint capacity: a preliminary investigation

In a short-term (eight days) double-blind crossover study involving 10 obese patients, the effects of dexfenfluramine on glucose and lipid metabolism were examined. The protocol comprised whole body in vivo measurements (hyperinsulinemic euglycemic clamp in combination with indirect calorimetry) and in vitro studies of isolated adipocytes (lipolysis and glucose transport). All study participants were weight stable during the study period (103.1±3.2, placebo vs 103.3±3.1 kg, dexfenfluramine, NS). The following parameters were significantly reduced after dexfenfluramine treatment: fasting levels of plasma glucose (6.2±0.2 vs 5.7±0.2 mmol/l, p<0.01), serum insulin (168.0±14.5 vs 138.9±7.9 pmol/l, p<0.05), serum C-peptide (0.68±0.03 vs 0.58±0.02 nmol/l, p<0.05) and total serum cholesterol (6.07±0.41 vs 5.48±0.38 mmol/l, p< 0.01). In the basal state glucose oxidation rate was significantly reduced by 36% (p<0.001), whereas non-oxidative glucose disposal was significantly increased by 41% (p<0.01), following dexfenfluramine treatment. Insulin-stimulated (2 mU·kg−1·min−1) glucose disposal rate tended to be increased (18%, p=0.10) after dexfenfluramine. In conclusion, dexfenfluramine possesses beneficial regulatory effects on glucose and lipid metabolism in non-diabetic obese patients, independently of weight loss.

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Effect of α-Lipoic Acid Combined with Creatine Monohydrate on Human Skeletal Muscle Creatine and Phosphagen Concentration

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.13.3.294 ◽

2003 ◽

Vol 13 (3) ◽

pp. 294-302 ◽

Cited By ~ 25

Author(s):

Darren G. Burke ◽

Philip D. Chilibeck ◽

Gianni Parise ◽

Mark A. Tarnopolsky ◽

Darren G. Candow

Keyword(s):

Skeletal Muscle ◽

Lipoic Acid ◽

Human Skeletal Muscle ◽

Vastus Lateralis ◽

Creatine Supplementation ◽

Creatine Monohydrate ◽

Glucose Disposal ◽

Creatine Uptake ◽

Total Creatine ◽

Muscle Creatine

α-lipoic acid has been found to enhance glucose uptake into skeletal muscle in animal models. Studies have also found that the co-ingestion of carbohydrate along with creatine increases muscle creatine uptake by a process related to insulin-stimulated glucose disposal. The purpose of this study was to determine the effect of α-lipoic acid on human skeletal muscle creatine uptake by directly measuring intramuscular concentrations of creatine, phosphocreatine, and ad-enosine triphosphate when creatine monohydrate was co-ingested with α-lipoic acid. Muscle biopsies were acquired from the vastus lateralis m. of 16 male subjects (18–32 y) before and after the experimental intervention. After the initial biopsy, subjects ingested 20 g · d−1 of creatine monohydrate, 20 g · d−1 of creatine monohydrate + 100 g · d−1 of sucrose, or 20 g · d−1 of creatine monohydrate + 100 g · d−1 of sucrose + 1000 mg · d−1 of α-lipoic acid for 5 days. Subjects refrained from exercise and consumed the same balanced diet for 7 days. Body weight increased by 2.1% following the nutritional intervention, with no differences between the groups. There was a significant increase in total creatine concentration following creatine supplementation, with the group ingesting α-lipoic acid showing a significantly greater increase (p < .05) in phosphocreatine (87.6 → 106.2 mmol · kg−1 dry mass [dm]) and total creatine (137.8 → 156.8 mmol · kg−1 dm). These findings indicate that co-ingestion of α-lipoic acid with creatine and a small amount of sucrose can enhance muscle total creatine content as compared to the ingestion of creatine and sucrose or creatine alone.

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Global and targeted gene expression and protein content in skeletal muscle of young men following short-term creatine monohydrate supplementation

Physiological Genomics ◽

10.1152/physiolgenomics.00157.2007 ◽

2008 ◽

Vol 32 (2) ◽

pp. 219-228 ◽

Cited By ~ 74

Author(s):

Adeel Safdar ◽

Nicholas J. Yardley ◽

Rodney Snow ◽

Simon Melov ◽

Mark A. Tarnopolsky

Keyword(s):

Gene Expression ◽

Skeletal Muscle ◽

Mrna Expression ◽

Protein Content ◽

Cellular Response ◽

Glycogen Synthesis ◽

Creatine Monohydrate ◽

Fat Free Mass ◽

Cell Swelling ◽

Short Term

Creatine monohydrate (CrM) supplementation has been shown to increase fat-free mass and muscle power output possibly via cell swelling. Little is known about the cellular response to CrM. We investigated the effect of short-term CrM supplementation on global and targeted mRNA expression and protein content in human skeletal muscle. In a randomized, placebo-controlled, crossover, double-blind design, 12 young, healthy, nonobese men were supplemented with either a placebo (PL) or CrM (loading phase, 20 g/day × 3 days; maintenance phase, 5 g/day × 7 days) for 10 days. Following a 28-day washout period, subjects were put on the alternate supplementation for 10 days. Muscle biopsies of the vastus lateralis were obtained and were assessed for mRNA expression (cDNA microarrays + real-time PCR) and protein content (Kinetworks KPKS 1.0 Protein Kinase screen). CrM supplementation significantly increased fat-free mass, total body water, and body weight of the participants ( P < 0.05). Also, CrM supplementation significantly upregulated (1.3- to 5.0-fold) the mRNA content of genes and protein content of kinases involved in osmosensing and signal transduction, cytoskeleton remodeling, protein and glycogen synthesis regulation, satellite cell proliferation and differentiation, DNA replication and repair, RNA transcription control, and cell survival. We are the first to report this large-scale gene expression in the skeletal muscle with short-term CrM supplementation, a response that suggests changes in cellular osmolarity.

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Regulation of skeletal muscle energy/nutrient-sensing pathways during metabolic adaptation to fasting in healthy humans

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00215.2014 ◽

2014 ◽

Vol 307 (10) ◽

pp. E885-E895 ◽

Cited By ~ 17

Author(s):

Marjolein A. Wijngaarden ◽

Leontine E. H. Bakker ◽

Gerard C. van der Zon ◽

Peter A. C. 't Hoen ◽

Ko Willems van Dijk ◽

...

Keyword(s):

Skeletal Muscle ◽

Protein Kinase ◽

Lipid Oxidation ◽

Energy Homeostasis ◽

Nutrient Sensing ◽

Whole Body ◽

Metabolic Adaptation ◽

Protein Kinase Activity ◽

Short Term ◽

Muscle Energy

During fasting, rapid metabolic adaptations are required to maintain energy homeostasis. This occurs by a coordinated regulation of energy/nutrient-sensing pathways leading to transcriptional activation and repression of specific sets of genes. The aim of the study was to investigate how short-term fasting affects whole body energy homeostasis and skeletal muscle energy/nutrient-sensing pathways and transcriptome in humans. For this purpose, 12 young healthy men were studied during a 24-h fast. Whole body glucose/lipid oxidation rates were determined by indirect calorimetry, and blood and skeletal muscle biopsies were collected and analyzed at baseline and after 10 and 24 h of fasting. As expected, fasting induced a time-dependent decrease in plasma insulin and leptin levels, whereas levels of ketone bodies and free fatty acids increased. This was associated with a metabolic shift from glucose toward lipid oxidation. At the molecular level, activation of the protein kinase B (PKB/Akt) and mammalian target of rapamycin pathways was time-dependently reduced in skeletal muscle during fasting, whereas the AMP-activated protein kinase activity remained unaffected. Furthermore, we report some changes in the phosphorylation and/or content of forkhead protein 1, sirtuin 1, and class IIa histone deacetylase 4, suggesting that these pathways might be involved in the transcriptional adaptation to fasting. Finally, transcriptome profiling identified genes that were significantly regulated by fasting in skeletal muscle at both early and late time points. Collectively, our study provides a comprehensive map of the main energy/nutrient-sensing pathways and transcriptomic changes during short-term adaptation to fasting in human skeletal muscle.

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Effect of short-term creatine monohydrate supplementation on indirect markers of cellular damage in young soccer players

Science & Sports ◽

10.1016/j.scispo.2011.06.001 ◽

2012 ◽

Vol 27 (2) ◽

pp. 88-93 ◽

Cited By ~ 1

Author(s):

S. Atashak ◽

A. Jafari

Keyword(s):

Creatine Monohydrate ◽

Cellular Damage ◽

Soccer Players ◽

Short Term

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