Molecular mechanisms of glutamine action

Curi, Rui; Lagranha, Cláudia Jacques; Doi, Sonia Q.; Sellitti, Donald F.; Procópio, Joaquim; Pithon-Curi, Tânia Cristina; Corless, M; Newsholme, Philip

doi:10.1002/jcp.20339

Cited by 416 publications

(351 citation statements)

References 129 publications

Supporting

Mentioning

308

Contrasting

Unclassified

Order By: Relevance

“…The ultimate fate of the glutamine extracted in the splanchnic bed remains to be elucidated. Glutamine is known to play a pivotal role in the gut, because glutamine not only serves as a preferred fuel for the enterocytes but also helps maintain rates of intestinal protein synthesis (8,30,31) and cell integrity and stimulates immune function as well (9). During inflammation, increased glutamine consumption by lymphocytes and macrophages in gut-associated lymphoid tissue (GALT) could occur, as these cells are avidly utilizing glutamine (27).…”

Section: Discussionmentioning

confidence: 99%

Corticosteroids increase glutamine utilization in human splanchnic bed

Thibault

Welch²,

Mauras³

et al. 2008

American Journal of Physiology-Gastrointestinal and Liver Physi

View full text Add to dashboard Cite

Thibault R, Welch S, Mauras N, Sager B, Altomare A, Haymond M, Darmaun D. Corticosteroids increase glutamine utilization in human splanchnic bed. Am J Physiol Gastrointest Liver Physiol 294: G548-G553, 2008. First published December 27, 2007 doi:10.1152/ajpgi.00461.2007.-Glutamine is the most abundant amino acid in the body and is extensively taken up in gut and liver in healthy humans. To determine whether glucocorticosteroids alter splanchnic glutamine metabolism, the effect of prednisone was assessed in healthy volunteers using isotope tracer methods. Two groups of healthy adults received 5-h intravenous infusions of L-[1-14 C]leucine and L-[ 2 H5]glutamine, along with q. 20 min oral sips of tracer doses of L-[1-13 C]glutamine in the fasting state, either 1) at baseline (control group; n ϭ 6) or 2) after a 6-day course of 0.8 mg ⅐ kg Ϫ1 ⅐ day Ϫ1 prednisone (prednisone group; n ϭ 8). Leucine and glutamine appearance rates (Ra) were determined from plasma [1-14 C]ketoisocaproate and [ 2 H5]glutamine, respectively, and leucine and glutamine oxidation from breath 14 CO2 and 13 CO2, respectively. Splanchnic glutamine extraction was estimated by the fraction of orally administered [ 13 C]glutamine that failed to appear into systemic blood. Prednisone treatment 1) did not affect leucine Ra or leucine oxidation; 2) increased plasma glutamine Ra, mostly owing to enhanced glutamine de novo synthesis (medians Ϯ interquartiles, 412 Ϯ 61 vs. 280 Ϯ 190 mol ⅐ kg Ϫ1 ⅐ h Ϫ1 , P ϭ 0.003); and 3) increased the fraction of orally administered glutamine undergoing extraction in the splanchnic territory (means Ϯ SE 64 Ϯ 6 vs. 42 Ϯ 12%, P Ͻ 0.05), without any change in the fraction of glutamine oxidized (means Ϯ SE, 75 Ϯ 4 vs. 77 Ϯ 4%, not significant). We conclude that high-dose glucocorticosteroids increase in splanchnic bed the glutamine requirements. The role of such changes in patients receiving chronic corticoid treatment for inflammatory diseases or suffering from severe illness remains to be determined. nutrition; protein metabolism; stable isotopes; stress; gut GLUTAMINE PLAYS AN IMPORTANT role in the maintenance of intestinal function (39,43,46). Glutamine indeed is both a preferred fuel (9, 47) for enterocytes and a precursor for the intestinal synthesis of purines, pyrimidines (9), and glutathione (37), and it may regulate gut protein synthesis (21,30,32). In addition, glutamine is a major donor of carbon for gluconeogenesis (19). This explains why glutamine is extensively extracted in the splanchnic tissues in several animal species (39,47).In humans, the concomitant infusion of two tracers of glutamine (one infused intravenously, the other one enterally) can be used to assess the extraction of glutamine by the splanchnic bed. By using this technique, ϳ50 to 75% of enterally administered glutamine undergoes first-pass extraction within the splanchnic bed, presumably by the gut and liver, in healthy humans (4, 17, 18, 34). Additionally, the major fate of splanchnic glutamine after enteral administration was oxidation, ...

show abstract

Section: Discussionmentioning

confidence: 99%

Corticosteroids increase glutamine utilization in human splanchnic bed

Thibault

Welch²,

Mauras³

et al. 2008

American Journal of Physiology-Gastrointestinal and Liver Physi

View full text Add to dashboard Cite

show abstract

“…Glutamine (Gln) plays an important role in promoting and maintaining the functions of various organs and cells in mammalian [1,2]. Studies demonstrated that Gln improves clinical antioxidant outcome in patients [3][4][5] and attenuates apoptosis in experimental rat [6][7][8].…”

Section: Introductionmentioning

confidence: 99%

The metabolites of glutamine prevent hydroxyl radical-induced apoptosis through inhibiting mitochondria and calcium ion involved pathways in fish erythrocytes

Jiang

Liu

et al. 2016

Free Radical Biology and Medicine

View full text Add to dashboard Cite

a b s t r a c tThe present study explored the apoptosis pathways in hydroxyl radicals ( • OH)-induced carp erythrocytes. Carp erythrocytes were treated with the caspase inhibitors in physiological carp saline (PCS) or Ca 2 þ -free PCS in the presence of 40 μM FeSO 4 /20 μM H 2 O 2 . The results showed that the generation of reactive oxygen species (ROS), the release of cytochrome c and DNA fragmentation were caspase-dependent, and Ca 2 þ was involved in calpain activation and phosphatidylserine (PS) exposure in • OH-induced carp erythrocytes. Moreover, the results suggested that caspases were involved in PS exposure, and Ca 2 þ was involved in DNA fragmentation in • OH-induced fish erythrocytes. These results demonstrated that there might be two apoptosis pathways in fish erythrocytes, one is the caspase and cytochrome c-dependent apoptosis that is similar to that in mammal nucleated cells, the other is the Ca 2 þ -involved apoptosis that was similar to that in mammal non-nucleated erythrocytes. So, fish erythrocytes may be used as a model for studying oxidative stress and apoptosis in mammal cells. Furthermore, the present study investigated the effects of glutamine (Gln)'s metabolites [alanine (Ala), citrulline (Cit), proline (Pro) and their combination (Ala 10 Pro 4 Cit 1 )] on the pathways of apoptosis in fish erythrocytes. The results displayed that Ala, Cit, Pro and Ala 10 Pro 4 Cit 1 effectively suppressed ROS generation, cytochrome c release, activation of caspase-3, caspase-8 and caspase-9 at the physiological concentrations, prevented Ca 2 þ influx, calpain activation, PS exposure, DNA fragmentation and the degradation of the cytoskeleton and oxidation of membrane and hemoglobin (Hb) and increased activity of anti-hydroxyl radical (AHR) in • OH-induced carp erythrocytes. Ala 10 Pro 4 Cit 1 produced a synergistic effect of inhibited oxidative stress and apoptosis in fish erythrocytes. These results demonstrated that Ala, Cit, Pro and their combination can protect mammal erythrocytes and nucleated cells against oxidative stress and apoptosis. The studies supported the use of Gln, Ala, Cit and Pro as oxidative stress and apoptosis inhibitors in mammal cells and the hypothesis that the inhibited effects of Gln on oxidative stress and apoptosis are at least partly dependent on that of its metabolites in mammalian.

show abstract

“…This suggests that weaning has adverse effects on mammals at the onset of segregation. L-Glutamine (Gln) serves as a major energy substrate for rapidly dividing cells (Marc Rhoads and Wu, 2009) and as a building block for polypeptides and proteins (Curi et al, 2005), but also as an essential precursor of bioactive molecules, such as glutathione, amino sugars, purines, and pyrimidines (Boza et al, 2000;Wu, 2009). The importance of Gln under hypermetabolic states, including those which occur during weaning, is now firmly established Marc Rhoads and Wu, 2009).…”

Section: Introductionmentioning

confidence: 99%

Response to weaning and dietary l-glutamine supplementation: metabolomic analysis in piglets by gas chromatography/mass spectrometry

Xiao

Hong

et al. 2012

J. Zhejiang Univ. Sci. B

View full text Add to dashboard Cite

A novel metabolomic method based on gas chromatography/mass spectrometry (GC-MS) was applied to determine the metabolites in the serum of piglets in response to weaning and dietary L-glutamine (Gln) supplementation. Thirty-six 21-d-old piglets were randomly assigned into three groups. One group continued to suckle from the sows (suckling group), whereas the other two groups were weaned and their diets were supplemented with 1% (w/w) Gln or isonitrogenous L-alanine, respectively, representing Gln group or control group. Serum samples were collected to characterize metabolites after a 7-d treatment. Results showed that twenty metabolites were down-regulated significantly (P<0.05) in control piglets compared with suckling ones. These data demonstrated that early weaning causes a wide range of metabolic changes across arginine and proline metabolism, aminosugar and nucleotide metabolism, galactose metabolism, glycerophospholipid metabolism, biosynthesis of unsaturated fatty acid, and fatty acid metabolism. Dietary Gln supplementation increased the levels of creatinine, D-xylose, 2-hydroxybutyric acid, palmitelaidic acid, and α-L-galactofuranose (P<0.05) in early weaned piglets, and were involved in the arginine and proline metabolism, carbohydrate metabolism, and fatty acid metabolism. A leave-one-out cross-validation of random forest analysis indicated that creatinine was the most important metabolite among the three groups. Notably, the concentration of creatinine in control piglets was decreased (P=0.00001) compared to the suckling piglets, and increased (P=0.0003) in Gln-supplemented piglets. A correlation network for weaned and suckling piglets revealed that early weaning changed the metabolic pathways, leading to the abnormality of carbohydrate metabolism, amino acid metabolism, and lipid metabolism, which could be partially improved by dietary Gln supplementation. These findings provide fresh insight into the complex metabolic changes in response to early weaning and dietary Gln supplementation in piglets.

show abstract

Molecular mechanisms of glutamine action

Cited by 416 publications

References 129 publications

Corticosteroids increase glutamine utilization in human splanchnic bed

Corticosteroids increase glutamine utilization in human splanchnic bed

The metabolites of glutamine prevent hydroxyl radical-induced apoptosis through inhibiting mitochondria and calcium ion involved pathways in fish erythrocytes

Response to weaning and dietary l-glutamine supplementation: metabolomic analysis in piglets by gas chromatography/mass spectrometry

Contact Info

Product

Resources

About