scholarly journals Glutamine as an Anti-Fatigue Amino Acid in Sports Nutrition

Nutrients ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 863 ◽  
Author(s):  
Audrey Yule Coqueiro ◽  
Marcelo Macedo Rogero ◽  
Julio Tirapegui
Keyword(s):  
Amino Acid ◽  
Glycogen Synthesis ◽  
Sports Nutrition ◽  
Glutamine Supplementation ◽  
Inclusion Criteria ◽  
Acid Base Balance ◽  
Ammonia Accumulation ◽  
Pubmed Database ◽  
Base Balance ◽  
And Performance

Glutamine is a conditionally essential amino acid widely used in sports nutrition, especially because of its immunomodulatory role. Notwithstanding, glutamine plays several other biological functions, such as cell proliferation, energy production, glycogenesis, ammonia buffering, maintenance of the acid-base balance, among others. Thus, this amino acid began to be investigated in sports nutrition beyond its effect on the immune system, attributing to glutamine various properties, such as an anti-fatigue role. Considering that the ergogenic potential of this amino acid is still not completely known, this review aimed to address the main properties by which glutamine could delay fatigue, as well as the effects of glutamine supplementation, alone or associated with other nutrients, on fatigue markers and performance in the context of physical exercise. PubMed database was selected to examine the literature, using the keywords combination “glutamine” and “fatigue”. Fifty-five studies met the inclusion criteria and were evaluated in this integrative literature review. Most of the studies evaluated observed that glutamine supplementation improved some fatigue markers, such as increased glycogen synthesis and reduced ammonia accumulation, but this intervention did not increase physical performance. Thus, despite improving some fatigue parameters, glutamine supplementation seems to have limited effects on performance.

Expression of colonic H-K-ATPase mRNA in cortical collecting duct: regulation by acid/base balance

1995 ◽  
Vol 269 (4) ◽  
pp. F551-F557 ◽  
Author(s):  
G. Fejes-Toth ◽  
E. Rusvai ◽  
K. A. Longo ◽  
A. Naray-Fejes-Toth
Keyword(s):  
Amino Acid ◽  
Collecting Duct ◽  
Predicted Amino Acid Sequence ◽  
Cortical Collecting Duct ◽  
Acid Base Balance ◽  
Acid Base ◽  
Pcr Product ◽  
Exact Function ◽  
Degenerate Oligonucleotide ◽  
Base Balance

In addition to the gastric isoform of H-K-ATPase, the colonic isoform is also expressed in the kidney, but its intrarenal localization and exact function are not known. The goal of this study was to determine whether the colonic H-K-ATPase is expressed in the rabbit cortical collecting duct (CCD) and whether it is regulated by changes in acid/base balance. With quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) with RNA isolated from immunodissected rabbit CCD cells and degenerate oligonucleotide primers, a PCR product of the predicted size (approximately 430 bp) was amplified. The amplified DNA was further characterized by nested PCR and sequencing. Direct sequencing of the 434-bp PCR product revealed 83% identity at the nucleotide level and an 80.4% identity at the deduced amino acid level to the rat colonic H-K-ATPase. With the same primers and cDNA originating from rabbit distal colon, a DNA fragment with a size and nucleotide sequence identical to that originating from CCD cells was amplified. Furthermore, using PCR screening, we isolated and sequenced a 1.5-kb cDNA clone from a rabbit CCD library. The predicted amino acid sequence of the protein encoded by this cDNA is 85 and 82% identical to the corresponding regions of the guinea pig and rat colonic H-K-ATPase, respectively, and 70% identical to the H-K-ATPase recently cloned from Bufo marinus, whereas it shows only 45 and 42% homology to the rat Na-K-ATPase alpha 1-subunit and the rat gastric H-K-ATPase, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Roles of urea production, ammonium excretion, and amino acid oxidation in acid-base balance

1986 ◽  
Vol 250 (2) ◽  
pp. F181-F188 ◽  
Author(s):  
W. Mackenzie
Keyword(s):  
Amino Acid ◽  
Acid Oxidation ◽  
Ammonium Excretion ◽  
Acid Base Balance ◽  
Acid Base ◽  
Amino Acid Oxidation ◽  
Titratable Acid ◽  
Urea Production ◽  
Base Balance ◽  
Oxidation Of Methionine

Atkinson and colleagues recently proposed several concepts that contrast with traditional views: first, that acid-base balance is regulated chiefly by the reactions leading to urea production in the liver; second, that ammonium excretion by the kidney plays no role in acid-base homeostasis; and third, that ammonium does not stimulate ureagenesis (except indirectly). To examine these concepts, plasma ions other than bicarbonate are categorized as 1) fixed cations (Na+, K+, Ca2+, and Mg2+, symbolized M+) and anions (Cl-), 2) buffer anions (A-), 3) other anions (X-), and 4) ammonium plus charged amino groups (N+). Since electroneutrality dictates that M+ + N+ = Cl- + HCO3- + A- + X-, it follows that delta HCO3- = delta(M+ - Cl-) - delta A- - delta X- + delta N+. Therefore acid-base disturbances (changes in HCO3-) can be categorized as to how they affect bodily content and hence plasma concentration of each of these four types of ions. The stoichiometry of ureagenesis, glutamine hydrolysis, ammonium and titratable acid excretion, oxidation of neutral, acidic, and basic amino acids, and oxidation of methionine, phosphoserine, and protein are examined to see how they alter these quantities. It is concluded that 1) although ureagenesis is pH dependent and also counteracts a tendency of amino acid oxidation to cause alkalosis, this tendency is inherently limited by the hyperammonemia (delta N+) that necessarily accompanies it, 2) ammonium excretion is equivalent to hydrogen excretion in its effects on acid-base balance if, and only if, it occurs in exchange for sodium or is accompanied by chloride excretion and only when the glutamate generated by glutamine hydrolysis is oxidized.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Effects of NaHCO3 loading on acid-base balance, lactate concentration, and performance in racing greyhounds

1998 ◽  
Vol 85 (3) ◽  
pp. 1037-1043 ◽  
Author(s):  
Lyle D. Kesl ◽  
Richard L. Engen
Keyword(s):  
Base Excess ◽  
Lactate Concentration ◽  
Acid Base Balance ◽  
Acid Base ◽  
Recovery Curves ◽  
Base Balance ◽  
And Performance ◽  
Performance Times ◽  
And Control ◽  
Acid Base Disturbance

This investigation examined the effects of NaHCO3 loading on lactate concentration ([La]), acid-base balance, and performance for a 603.5-m sprint task. Ten greyhounds completed a NaHCO3 (300 mg/kg body weight) and control trial in a crossover design. Results are expressed as means ± SE. Presprint differences ( P < 0.05) were found for NaHCO3 vs. control, respectively, for blood pH (7.47 ± 0.01 vs. 7.42 ± 0.01), [Formula: see text] (28.4 ± 0.4 vs. 23.5 ± 0.3 meq/l), and base excess (5.0 ± 0.3 vs. 0.2 ± 0.3 meq/l). Peak blood [La] increased ( P < 0.05) in NaHCO3 vs. control (20.4 ± 1.6 vs. 16.9 ± 1.3 mM, respectively). Relative to control, NaHCO3 produced a greater ( P < 0.05) reduction in blood base excess (−18.5 ± 1.4 vs. −14.1 ± 0.8 meq/l) and[Formula: see text] (−17.4 ± 1.2 vs. −12.8 ± 0.7 meq/l) from presprint to postexercise. Postexercise peak muscle H+concentration ([H+]) was higher ( P < 0.05) in NaHCO3 vs. control (158.8 ± 8.8 vs. 137.0 ± 5.3 nM, respectively). Muscle [H+] recovery half-time (7.2 ± 1.6 vs. 11.3 ± 1.6 min) and time to predose values (22.2 ± 2.4 vs. 32.9 ± 4.0 min) were reduced ( P < 0.05) in NaHCO3 vs. control, respectively. No differences were found in blood [H+] or blood [La] recovery curves or performance times. NaHCO3 increased postexercise blood [La] but did not reduce the muscle or blood acid-base disturbance associated with a 603.5-m sprint or significantly affect performance.

Higher Dietary Acidity is Associated with Lower Bone Mineral Density in Postmenopausal Iranian Women, Independent of Dietary Calcium Intake

2014 ◽  
Vol 84 (3-4) ◽  
pp. 0206-0217 ◽  
Author(s):  
Seyedeh-Elaheh Shariati-Bafghi ◽  
Elaheh Nosrat-Mirshekarlou ◽  
Mohsen Karamati ◽  
Bahram Rashidkhani
Keyword(s):  
Calcium Intake ◽  
Dietary Calcium ◽  
Dietary Calcium Intake ◽  
Dietary Intakes ◽  
Iranian Women ◽  
Acid Base Balance ◽  
Mineral Density ◽  
Acid Base ◽  
Base Balance ◽  
Dietary Acid

Findings of studies on the link between dietary acid-base balance and bone mass are relatively mixed. We examined the association between dietary acid-base balance and bone mineral density (BMD) in a sample of Iranian women, hypothesizing that a higher dietary acidity would be inversely associated with BMD, even when dietary calcium intake is adequate. In this cross-sectional study, lumbar spine and femoral neck BMDs of 151 postmenopausal women aged 50 - 85 years were measured using dual-energy x-ray absorptiometry. Dietary intakes were assessed using a validated food frequency questionnaire. Renal net acid excretion (RNAE), an estimate of acid-base balance, was then calculated indirectly from the diet using the formulae of Remer (based on dietary intakes of protein, phosphorus, potassium, and magnesium; RNAERemer) and Frassetto (based on dietary intakes of protein and potassium; RNAEFrassetto), and was energy adjusted by the residual method. After adjusting for potential confounders, multivariable adjusted means of the lumbar spine BMD of women in the highest tertiles of RNAERemer and RNAEFrassetto were significantly lower than those in the lowest tertiles (for RNAERemer: mean difference -0.084 g/cm2; P=0.007 and for RNAEFrassetto: mean difference - 0.088 g/cm2; P=0.004). Similar results were observed in a subgroup analysis of subjects with dietary calcium intake of >800 mg/day. In conclusion, a higher RNAE (i. e. more dietary acidity), which is associated with greater intake of acid-generating foods and lower intake of alkali-generating foods, may be involved in deteriorating the bone health of postmenopausal Iranian women, even in the context of adequate dietary calcium intake.

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