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Beneficial effects of l-arginine on reducing obesity: Potential mechanisms and important implications for human health

Department of Animal Science, Faculty of Nutrition, Texas A&M University, College Station, TX 77843, USA.
Amino Acids (Impact Factor: 3.65). 05/2010; 39(2):349-57. DOI: 10.1007/s00726-010-0598-z
Source: PubMed

ABSTRACT Over the past 20 years, growing interest in the biochemistry, nutrition, and pharmacology of L-arginine has led to extensive studies to explore its nutritional and therapeutic roles in treating and preventing human metabolic disorders. Emerging evidence shows that dietary L-arginine supplementation reduces adiposity in genetically obese rats, diet-induced obese rats, finishing pigs, and obese human subjects with Type-2 diabetes mellitus. The mechanisms responsible for the beneficial effects of L-arginine are likely complex, but ultimately involve altering the balance of energy intake and expenditure in favor of fat loss or reduced growth of white adipose tissue. Recent studies indicate that L-arginine supplementation stimulates mitochondrial biogenesis and brown adipose tissue development possibly through the enhanced synthesis of cell-signaling molecules (e.g., nitric oxide, carbon monoxide, polyamines, cGMP, and cAMP) as well as the increased expression of genes that promote whole-body oxidation of energy substrates (e.g., glucose and fatty acids) Thus, L-arginine holds great promise as a safe and cost-effective nutrient to reduce adiposity, increase muscle mass, and improve the metabolic profile in animals and humans.

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    • "Thus, arginine may beneficially improve the quality of beef and pork in animal production. This is in contrast to the ability of arginine to depress adiposity in rodents and humans (McKnight et al. 2010; Wu 2013). The basis for the difference in effects of arginine on adiposity between humans, rats, pigs, and cattle may lie in the fact that, in livestock species, adipose tissue is the primary site of de novo fatty acid biosynthesis (Mersmann et al. 1973; Hanson and Ballard 1967). "
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    ABSTRACT: Based on previous research with bovine peadipocytes, we hypothesized that infusion of arginine into the abomasum of Angus steers stimulates stearoyl-CoA desaturase (SCD) gene expression in bovine subcutaneous (s.c.) adipose tissue, and that this would be attenuated by conjugated linoleic acid (CLA). Growing Angus steers were infused abomasally with L-arginine 50 g/day; n = 13; provided as L-arginine HCl) or L-alanine (isonitrogenous control, 100 g/day; n = 11) for 14 days. For the subsequent 14 days, half of the steers in each amino acid group were infused with CLA (100 g/day). Body weight gain and average daily gain were unaffected (P > 0.15) by infusion of arginine or CLA into the abomasum. The plasma concentrations of cis-9, trans-11 and trans-10, cis-12 CLA were increased CLA infusion (P = 0.001) and infusion of arginine increased plasma arginine (P = 0.01). Compared with day 0, fatty acid synthase, glucose-6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase enzyme activities in s.c. adipose tissue increased by day 14 in steers infused with either alanine or arginine (all P < 0.01). NADP-MDH activity was higher (P = 0.01) in steers infused with arginine than in steers infused with arginine plus CLA by day 28, but lipid synthesis in vitro from glucose and acetate was unaffected by infusion of either arginine or CLA (P > 0.40). By day 28, C/EBPβ and SCD gene expression was higher, and CPT1β gene expression was lower, in s.c. adipose tissue of steers infused with arginine than in steers infused with alanine (±CLA) (P = 0.05). CLA decreased adipose tissue oleic acid (18:1n-9) in alanine- or arginine-infused steers (P = 0.05), although CLA had no effect on SCD gene expression. The data indicate that supplemental arginine promotes adipogenic gene expression and may promote lipid accumulation in bovine adipose tissue. L-Arginine may beneficially improve beef quality for human consumption.
    Amino Acids 12/2013; DOI:10.1007/s00726-013-1622-x · 3.65 Impact Factor
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    • "This reduction was higher compared to diabetic animals without supplementation, and it represent one-third of the weight reached by animals supplemented with L-arginine by itself. Reasons for this reduction are unclear, but recently Mcknight et al. [41] reviewed data available in the literature showing that dietary L-arginine supplementation reduces adiposity in several human and animal models of obesity and type 2 diabetes mellitus, a phenomenon associated to reduction in the growth of white adipose tissue. Contrarily to previous reports [10] [11] [14] showing reduction in glycemia after L-arginine supplementation in alloxaninduced diabetes, we found no significant changes in respect to diabetic animals without supplementation. "
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    ABSTRACT: Supplementation with L-arginine or fresh food with high content of this amino acid is associated with favorable effects in the metabolic control of diabetes. We aimed to determine whether supplementation with apples enriched with L-arginine offer additional benefits compared to L-arginine by itself in a preclinical study of diabetes. This study combines food-engineer technologies with in vivo and in vitro analysis. In vitro experiments show that cells derived from non-diabetic animals and exposed to high glucose (25 mM, 12 H) and cells isolated from alloxan-induced diabetic animals exhibited a reduction (∼50%) in the L-arginine uptake. This effect was reverted by L-arginine pretreatment (12 H) in both the normal and diabetes-derived cells. In preclinical studies, normoglycemic (n = 25) and diabetic groups (n = 50) were divided into subgroups that received either L-arginine (375 mg/kg per 10 days) or apple enriched with L-arginine or vehicle (control). In a preliminary analysis, supplementation with L-arginine by itself (50%) or apple enriched with L-arginine (100%) improve survival rate in the diabetic group compared to control (0%) at the end of the follow up (17 days). This phenomenon was associated with a partial but sustained high plasma level of L-arginine, as well as plasma concentration of nitrites and insulin in the L-arginine or apple + L-arginine groups after supplementation. Apple + L-arginine supplementation in diabetic animals induced the highest and longest effects in the level of these three markers among the studied groups. Therefore, apple enriched by L-arginine offers more benefits than L-arginine by itself in this preclinical study. © 2013 BioFactors, 2013.
    BioFactors 09/2013; 39(5). DOI:10.1002/biof.1103 · 3.00 Impact Factor
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    • "Dietary restriction periods are classically associated with fat loss but are also characterized by a definitively harmful decrease in lean body mass. Numerous nutritional strategies have been proposed to counteract this regimen-related side-effect (Bopp et al. 2008; Chaston et al. 2007; McKnight et al. 2010; Wycherley et al. 2012). Muscle mass loss is generally associated with a decrease in strength. "
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    Amino Acids 08/2013; 45(5). DOI:10.1007/s00726-013-1564-3 · 3.65 Impact Factor
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