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h2s
11-12-2012, 11:18 AM
Vitamin D status affects strength gains in older adults supplemented with a combination of β-hydroxy-β-methylbutyrate, arginine, and lysine: a cohort study.


Vitamin D status affects strength gains in older adults supplemented with a combination of β-hydroxy-β-methylbutyrate, arginine, and lysine: a cohort study.
Fuller JC Jr, Baier S, Flakoll P, Nissen SL, Abumrad NN, Rathmacher JA.
Source

Metabolic Technologies, Inc, Iowa State University Research Park, Ames, USA.
Abstract
BACKGROUND:

Older adults supplemented for 1 year with β-hydroxy-β-methylbutyrate, arginine, and lysine (HMB/ARG/LYS) were previously shown to have significant gains in fat-free mass (FFM) but not muscular strength.
OBJECTIVE:

Recently, increasing levels of serum vitamin D have been associated with an increase in muscle function, particularly in the elderly. To determine if vitamin D status may have limited strength gain in participants supplemented with HMB/ARG/LYS, the authors performed post hoc analysis of strength based on the participants' vitamin D status.
METHODS:

Elderly (age 76.0 1.6 years) adults were recruited for a double-blinded, controlled study and were randomly assigned to either an isonitrogenous control (n = 37) or HMB/ARG/LYS (n = 40) for the yearlong study. Participants were further segregated based on their vitamin D status of either <30 or ≥30 ng 25OH-vitD(3)/mL serum, and an analysis was performed on the 4 cohorts.
RESULTS:

Regardless of vitamin D status, HMB/ARG/LYS resulted in significantly increased FFM (P < .02), but only in those with vitamin D status ≥30 ng 25OH-vitD(3)/mL was there a significant increase in strength with HMB/ARG/LYS (P < .01). Control-supplemented participants, regardless of vitamin D status, and the HMB/ARG/LYS-supplemented participants with vitamin D status <30 ng 25OH-vitD(3) failed to show improvements in strength.
CONCLUSIONS:

The nutrient cocktail of HMB/ARG/LYS alone was effective in increasing muscle mass regardless of vitamin D status, but accompanying strength increases were observed only when participants also had adequate vitamin D status indicating a synergistic effect between the HMB/ARG/LYS and vitamin D.

Vitamin D status affects streng... [JPEN J Parenter Enteral Nutr. 2011] - PubMed - NCBI (http://www.ncbi.nlm.nih.gov/pubmed/21807930)

h2s
11-18-2012, 02:11 PM
Dietary Supplementation of L-Arginine and Conjugated Linoleic Acid Reduces Retroperitoneal Fat Mass and Increases Lean Body Mass in Rats


We hypothesized that L-arginine and conjugated linoleic acid (CLA) would have additive effects in decreasing adiposity. Sprague Dawley rats were assigned to the following dietary groups (n = 6/group; 5 wk total): 1) control (2.55% L-alanine plus 1.5% canola oil); 2) arginine (1.25% L-arginine plus 1.5% canola oil); 3) CLA (2.55% L-alanine plus 1.5% CLA); and 4) arginine plus CLA (1.25% L-arginine plus 1.5% CLA). Supplemental amino acids were provided in drinking water and CLA was incorporated into the food pellets. Daily weight gain, food intake, arginine intake, and final body and eviscerated body weights were greater in rats fed supplemental CLA then in rats fed canola oil. The retroperitoneal adipose tissue:body weight ratio was less in rats fed supplemental CLA than in rats fed canola oil, but epididymal adipose tissue, liver, and soleus and extensor digitorum longus muscle weights were unaffected by arginine or CLA. CLA decreased epididymal adipose tissue concentrations of palmitoleic, oleic, and cis-vaccenic acid. CLA and arginine increased palmitate oxidation to CO2 in epididymal adipose tissue in vitro relative to control rats. Glucose and palmitate incorporation into total lipids in epididymal adipose tissue was lower in rats fed supplemental arginine than in alanine-fed rats. Arginine increased plasma glycerol relative to alanine-fed rats and CLA and arginine independently decreased most serum essential amino acids and alanine, glutamate, glutamine, and ornithine. We conclude that CLA and arginine modulated adipose tissue metabolism by separate, but not additive, effects. Also, CLA and arginine may have depressed muscle protein turnover.

Dietary Supplementation of l-Arginine and Conjugated Linoleic Acid Reduces Retroperitoneal Fat Mass and Increases Lean Body Mass in Rats (http://jn.nutrition.org/content/early/2009/05/13/jn.108.102301.abstract)

harbonah
11-21-2012, 12:48 AM
The chronic oral administration of arginine aspartate decreases secretion of IGF-1 and IGFBP-3 in healthy volunteers.



The chronic oral administration of arginine aspartate decreases secretion of IGF-1 and IGFBP-3 in healthy volunteers.

Abstract
To investigate the effect of chronic oral arginine aspartate on the growth hormone (GH), GH-releasing hormone (GHRH), insulin-like growth factor-1 (IGF-1) and IGF-binding protein-3 (IGFBP-3) secretions in healthy volunteers. Twenty-three healthy non-athlete volunteer males were administered arginine aspartate (30 g) orally once daily at 21:00 h for 21 consecutive days. Subjects were hospitalized on days 0, 1, 3, 5, 7, 14 and 21 of treatment. At each hospitalization, concentrations of GHRH, GH, IGF-1 and IGFBP-3 were measured over 4 h after arginine aspartate intake. GH, IGF-1 and IGFBP-3 concentrations were also determined over 12 h at days 0, 1 and 21. Compared with day 1, 4 h GH levels dropped at day 5 and subsequently rose to levels not significantly different from initial ones. The latter was substantiated by 12 h GH levels that did not significantly change from days 1 to 21. GHRH levels were not statistically different, although there was a trend in median values that seemed to inversely mirror those of GH. This dynamic over the course of the study for GH and GHRH was accompanied by a general decrease in IGF-1 and IGFBP-3. In healthy volunteers, a chronic oral treatment with 30 g/day arginine aspartate is followed by a decrease in IGF-1 and IGFBP-3 secretions.



The chronic oral administration of arginine aspartate decreases secretion of IGF-1 and IGFBP-3 in healthy volunteers. (http://www.ncbi.nlm.nih.gov/pubmed/19527301)

Mr_math
11-21-2012, 01:35 PM
Effect of oral L-arginine supplementation on blood pressure: a meta-analysis of randomized, double-blind, placebo-controlled trials


Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, Suzhou, China.

Abstract
BACKGROUND: Previous studies suggest that L-arginine, an amino acid and a substrate of nitric oxide synthase, may have blood pressure (BP)-lowering effect. Because some studies were performed with limited number of patients with hypertension and therefore limited statistical power with sometimes inconsistent results, we aimed to examine the effect of oral L-arginine supplementation on BPby conducting a meta-analysis of randomized, double-blind, placebo-controlled trials.

METHODS: PubMed, Cochrane Central Register of Controlled Trials, and the ClinicalTrials.gov databases were searched through June 2011 to identify randomized, double-blind, placebo-controlled trials of oral L-arginine supplementation on BP in humans. We also reviewed reference lists of obtained articles. Either a fixed-effects or, in the presence of heterogeneity, a random-effects model was used to calculate the combined treatment effect.

RESULTS: We included 11 randomized, double-blind, placebo-controlled trials involving 387 participants with oral L-arginine intervention ranging from 4 to 24 g/d. Compared with placebo, L-arginine intervention significantly lowered systolic BP by 5.39 mm Hg (95% CI -8.54 to -2.25, P = .001) and diastolic BP by 2.66 mm Hg (95% CI -3.77 to -1.54, P < .001). Sensitivity analyses restricted to trials with a duration of 4 weeks or longer and to trials in which participants did not use antihypertensive medications yielded similar results. Meta-regression analysis suggested an inverse, though insignificant (P = .13), relation between baseline systolic BP and net change in systolic BP.

CONCLUSIONS: This meta-analysis provides further evidence that oral L-arginine supplementation significantly lowers both systolic and diastolic BP.

Copyright 2011 Mosby, Inc. All rights reserved.

Effect of oral L-arginine supplementati - PubMed Mobile (http://www.ncbi.nlm.nih.gov/m/pubmed/22137067/?i=4&from=l%20arginine%20lowers%20blood%20pressure)