Prolonged submaximal eccentric exercise is associated with increased levels of plasma IL-6

1997 ◽  
Vol 273 (1) ◽  
pp. E85-E91 ◽  
Author(s):  
T. Rohde ◽  
D. A. MacLean ◽  
E. A. Richter ◽  
B. Kiens ◽  
B. K. Pedersen
Keyword(s):  
Eccentric Exercise ◽  
Proliferative Response ◽  
Muscle Protein ◽  
Plasma Concentrations ◽  
Cytokine Response ◽  
Cytotoxic Activities ◽  
Branched Chain Amino Acid ◽  
Muscle Protein Degradation ◽  
Branched Chain ◽  
The Relationship

To study the relationship between exercise-related muscle proteolysis and the cytokine response, a prolonged eccentric exercise model of one leg was used. Subjects performed two trials [a branched-chain amino acid (BCAA) supplementation and a control trial]. The release of amino acids from muscle during and after the eccentric exercise was decreased in the BCAA trial, suggesting a suppression of net muscle protein degradation. The plasma concentrations of interleukin (IL)-6 increased from 0.75 +/- 0.19 (preexercise) to 5.02 +/- 0.96 pg/ml (2 h postexercise) in the control trial and in the BCAA supplementation trial from 1.07 +/- 0.41 to 4.15 +/- 1.21 pg/ml. Eccentric exercise had no effect on the concentrations of neutrophils, lymphocytes, CD16+/CD56+, CD4+, CD8+, CD14+/CD38+, lymphocyte proliferative response, or cytotoxic activities. BCAA supplementation reduced the concentration of CD14+/CD38+ cells. This study shows that the concentration of IL-6 in plasma is increased after prolonged eccentric exercise and suggests that the cytokine response is independent of the muscle proteolysis that occur during exercise.

Isolated Leucine and Branched-Chain Amino Acid Supplementation for Enhancing Muscular Strength and Hypertrophy: A Narrative Review

2021 ◽  
pp. 1-10
Author(s):  
Daniel L. Plotkin ◽  
Kenneth Delcastillo ◽  
Derrick W. Van Every ◽  
Kevin D. Tipton ◽  
Alan A. Aragon ◽  
...  
Keyword(s):  
Muscular Strength ◽  
Longitudinal Research ◽  
Muscle Protein ◽  
Evidence Based ◽  
Amino Acid Supplementation ◽  
Leucine Supplementation ◽  
Branched Chain Amino Acid ◽  
Practical Standpoint ◽  
Muscle Protein Metabolism ◽  
Branched Chain

Branched-chain amino acids (BCAA) are one of the most popular sports supplements, marketed under the premise that they enhance muscular adaptations. Despite their prevalent consumption among athletes and the general public, the efficacy of BCAA has been an ongoing source of controversy in the sports nutrition field. Early support for BCAA supplementation was derived from extrapolation of mechanistic data on their role in muscle protein metabolism. Of the three BCAA, leucine has received the most attention because of its ability to stimulate the initial acute anabolic response. However, a substantial body of both acute and longitudinal research has now accumulated on the topic, affording the ability to scrutinize the effects of BCAA and leucine from a practical standpoint. This article aims to critically review the current literature and draw evidence-based conclusions about the putative benefits of BCAA or leucine supplementation on muscle strength and hypertrophy as well as illuminate gaps in the literature that warrant future study.

scholarly journals Branched-Chain Amino Acid Oxidation Is Elevated in Adults with Morbid Obesity and Decreases Significantly after Sleeve Gastrectomy

2020 ◽  
Vol 150 (12) ◽  
pp. 3180-3189
Author(s):  
Hong Chang Tan ◽  
Jean W Hsu ◽  
Jean-Paul Kovalik ◽  
Alvin Eng ◽  
Weng Hoong Chan ◽  
...  
Keyword(s):  
Morbid Obesity ◽  
Sleeve Gastrectomy ◽  
Plasma Concentrations ◽  
Fat Free Mass ◽  
Acid Oxidation ◽  
Morbidly Obese ◽  
Healthy Weight ◽  
Leucine Oxidation ◽  
Branched Chain Amino Acid ◽  
Branched Chain

ABSTRACT Background Plasma concentrations of branched-chain amino acids (BCAAs) are elevated in obese individuals with insulin resistance (IR) and decrease after bariatric surgery. However, the metabolic mechanisms are unclear. Objectives Our objectives are to compare leucine kinetics between morbidly obese and healthy-weight individuals cross-sectionally, and to prospectively evaluate changes in the morbidly obese after sleeve gastrectomy. We hypothesized that leucine oxidation is slower in obese individuals and increases after surgery. Methods Ten morbidly obese [BMI (in kg/m2) ≥32.5, age 21–50 y] and 10 healthy-weight participants (BMI <25), matched for age (median ∼30 y) but not gender, were infused with [U-13C6] leucine and [2H5] glycerol to quantify leucine and glycerol kinetics. Morbidly obese participants were studied again 6 mo postsurgery. Primary outcomes were kinetic parameters related to BCAA metabolism. Data were analyzed by nonparametric methods and presented as median (IQR). Results Participants with obesity had IR with an HOMA-IR (4.89; 4.36–8.76) greater than that of healthy-weight participants (1.32; 0.99–1.49; P < 0.001) and had significantly faster leucine flux [218; 196–259 compared with 145; 138–149 μmol · kg fat-free mass (FFM)−1 · h−1], oxidation (24.0; 17.9–29.8 compared with 16.1; 14.3–18.5 μmol · kg FFM−1 · h−1), and nonoxidative disposal (204; 190–247 compared with 138; 129–140 μmol · kg FFM−1 · h−1) (P < 0.017 for all). After surgery, the morbidly obese had a marked improvement in IR (3.54; 3.06–6.08; P = 0.008) and significant reductions in BCAA concentrations (113; 95–157 μmol/L) and leucine oxidation (9.37; 6.85–15.2 μmol · kg FFM−1 · h−1) (P = 0.017 for both). Further, leucine flux in this group correlated significantly with IR (r = 0.78, P < 0.001). Conclusions BCAA oxidation is not impaired but elevated in individuals with morbid obesity. Plasma BCAA concentrations are lowered after surgery owing to slower breakdown of body proteins as insulin's ability to suppress proteolysis is restored. These findings suggest that IR is the underlying cause and not the consequence of elevated BCAAs in obesity.

Hyperglycemia after protein ingestion concurrent with injection of a GLP-1 receptor agonist in rats: a possible role for dietary peptides

2005 ◽  
Vol 289 (3) ◽  
pp. R688-R694 ◽  
Author(s):  
Alfred Aziz ◽  
G. Harvey Anderson ◽  
Adria Giacca ◽  
France Cho
Keyword(s):  
Amino Acid ◽  
Receptor Agonist ◽  
Plasma Concentrations ◽  
Intact Proteins ◽  
Branched Chain Amino Acid ◽  
Protein Ingestion ◽  
Amino Acid Mixtures ◽  
Glucagon Like Peptide 1 ◽  
Branched Chain ◽  
Amino Acid Concentrations

Protein ingestion after injection of the glucagon-like peptide-1 receptor agonist Exendin-4 (Ex-4) causes hyperglycemia in rats. The objectives of this study were to determine the components of protein digestion responsible for this effect and to associate it with changes in the concentrations of other metabolites and hormones. Two experiments were conducted. In the first experiment, food-deprived rats were gavaged with intact whey (WP) or albumin protein, their hydrolysates, amino acid mixtures (1 g/2.5 ml), or water 5 min after injection of either PBS or Ex-4 (0.5 μg/rat). Tail vein blood was analyzed for glucose over 2 h. In the second experiment, food-deprived rats were gavaged with WP with or without Ex-4. Groups of conscious rats were killed by decapitation either before, or at selected times after gavage. Plasma concentrations of glucose, amino acids, free fatty acids (FFA), glycerol, insulin, glucagon, and leptin were measured. In experiment 1, blood glucose was higher when intact proteins and protein hydrolysates, but not amino acid mixtures, were given with than without Ex-4 ( P < 0.05). In experiment 2, concentrations of glucose, FFA, and the ratio of tyrosine to branched-chain amino acid were higher ( P < 0.01), but leptin and essential amino acid concentrations were lower ( P < 0.05), and insulin, glucagon, and glycerol were similar when WP was given with or without Ex-4. We conclude that the hyperglycemia caused by the administration of Ex-4 concurrently with dietary protein arises from the action of peptides released during digestion and their interaction with Ex-4 in the regulation of glucose, fatty acid, and amino acid metabolism.

Effect of Infused Branched-Chain Amino Acids on Muscle and Whole-Body Amino Acid Metabolism in Man

1990 ◽  
Vol 79 (5) ◽  
pp. 457-466 ◽  
Author(s):  
Rita J. Louard ◽  
Eugene J. Barrett ◽  
Robert A. Gelfand
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Branched Chain Amino Acids ◽  
Whole Body ◽  
Acid Infusion ◽  
Amino Acid Infusion ◽  
Branched Chain Amino Acid ◽  
Branched Chain

1. Using the forearm balance method, together with systemic infusions of l-[ring-2,6-3H]phenylalanine and l-[1-14C]leucine, we examined the effects of infused branched-chain amino acids on whole-body and skeletal muscle amino acid kinetics in 10 postabsorptive normal subjects; 10 control subjects received only saline. 2. Infusion of branched-chain amino acids caused a four-fold rise in arterial branched-chain amino acid levels and a two-fold rise in branched-chain keto acids; significant declines were observed in circulating levels of most other amino acids, including phenylalanine, which fell by 34%. Plasma insulin levels were unchanged from basal levels (8 ± 1 μ-units/ml). 3. Whole-body phenylalanine flux, an index of proteolysis, was significantly suppressed by branched-chain amino acid infusion (P < 0.002), and forearm phenylalanine production was also inhibited (P < 0.03). With branched-chain amino acid infusion total leucine flux rose, with marked increments in both oxidative and non-oxidative leucine disposal (P < 0.001). Proteolysis, as measured by endogenous leucine production, showed a modest 12% decrease, although this was not significant when compared with saline controls. The net forearm balance of leucine and other branched-chain amino acids changed from a basal net output to a marked net uptake (P < 0.001) during branched-chain amino acid infusion, with significant stimulation of local leucine disposal. Despite the rise in whole-body non-oxidative leucine disposal, and in forearm leucine uptake and disposal, forearm phenylalanine disposal, an index of muscle protein synthesis, was not stimulated by infusion of branched-chain amino acids. 4. The results suggest that in normal man branched-chain amino acid infusion suppresses skeletal muscle proteolysis independently of any rise of plasma insulin. Muscle branched-chain amino acid uptake rose dramatically in the absence of any apparent increase in muscle protein synthesis, as measured by phenylalanine disposal, or in branched-chain keto acid release. Thus, an increase in muscle branched-chain amino acid concentrations and/ or local branched-chain amino acid oxidation must account for the increased disposal of branched-chain amino acids.

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