Glutamine protects intestine against ischemia-reperfusion injury by alleviating endoplasmic reticulum stress induced apoptosis in rats

Abstract Purpose Glutamine, as an essential part of enteral nutrition and parenteral nutrition agent, has been widely recognized to be a kind of important intestinal mucosa protectant in clinical practice and experimental research. However, the mechanisms of its protective effects are still not fully understand. Consequently, this study aimed to explore the potential mechanism of glutamine on ischemia-reperfusion (I/R) injury induced endoplasmic reticulum (ER) stress in intestine. Methods An experimental model of intestinal I/R in rats was established by 1 hour occlusion of the superior mesenteric artery followed by 3 hours of reperfusion. Morphologic changes of intestinal mucosa, apoptosis of epithelial cells, and expression of intestinal Grp78, Gadd153, Caspase-12, ATF4, PERK phosphorylation (P-PERK) and elF2αphosphorylation(P-elF2α) were determined. Results After I/R, the apoptotic index of intestinal mucosa epithelial cells observably increased with notable necrosis of intestinal mucosa, and the expressions of Grp78, Gadd153, Caspase-12, ATF4, P-PERK and P-elF2αall were increased. However, treatment with glutamine could significantly relieve intestinal I/R injury and apoptosis index. Moreover, glutamine could clearly up-regulate the expression of Grp78, restrain P-PERK and P-elF2α, and reduce ATF4, Gadd153 and Caspase-12 expressions. Conclusion Glutamine may be involved in alleviating ER stress induced intestinal mucosa cells apoptosis.

Kinetic properties of Streptomyces canarius L- Glutaminase and its anticancer efficiency

Abstract L-glutaminase was produced by Streptomyces canarius FR (KC460654) with an apparent molecular mass of 44 kDa. It has 17.9 purification fold with a final specific activity 132.2 U/mg proteins and 28% yield recovery. The purified L-glutaminase showed a maximal activity against L-glutamine when incubated at pH 8.0 at 40 °C for 30 min. It maintained its stability at wide range of pH from 5.0 11.0 and thermal stable up to 60 °C with Tm value 57.5 °C. It has high affinity and catalytic activity for L-glutamine (Km 0.129 mM, Vmax 2.02 U/mg/min), followed by L-asparagine and L-aspartic acid. In vivo, L-glutaminase showed no observed changes in liver; kidney functions; hematological parameters and slight effect on RBCs and level of platelets after 10 days of rabbit's injection. The anticancer activity of L-glutaminase was also tested against five types of human cancer cell lines using MTT assay in vitro. L-glutaminase has a significant efficiency against Hep-G2 cell (IC50, 6.8 μg/mL) and HeLa cells (IC50, 8.3 μg/mL), while the growth of MCF-7 cells was not affected. L-glutaminase has a moderate cytotoxic effect against HCT-116 cell (IC50, 64.7 μg/mL) and RAW 264.7 cell (IC50, 59.3 μg/mL).

Glutamine treatment attenuates hyperglycemia-induced mitochondrial stress and apoptosis in umbilical vein endothelial cells

OBJECTIVE: The aim of this study was to determine the in vitro effect of glutamine and insulin on apoptosis, mitochondrial membrane potential, cell permeability, and inflammatory cytokines in hyperglycemic umbilical vein endothelial cells. MATERIALS AND METHODS: Human umbilical vein endothelial cells were grown and subjected to glutamine and insulin to examine the effects of these agents on the hyperglycemic state. Mitochondrial function and the production of inflammatory cytokines were assessed using fluorescence analysis and multiple cytotoxicity assays. Apoptosis was analyzed by the terminal deoxynucleotidyl transferase dUTP nick end-labeling assay. RESULTS: Glutamine maintains the integrity of the mitochondria by reducing the cell permeability and cytochrome c levels and increasing the mitochondrial membrane potential. The cytochrome c level was significantly (p<0.005) reduced when the cells were treated with glutamine. An apoptosis assay revealed significantly reduced apoptosis (p<0.005) in the glutamine-treated cells. Moreover, glutamine alone or in combination with insulin modulated inflammatory cytokine levels. Interleukin-10, interleukin-6, and vascular endothelial growth factor were up-regulated while tumor necrosis factor-α was down-regulated after treatment with glutamine. CONCLUSION: Glutamine, either alone or in combination with insulin, can positively modulate the mitochondrial stress and cell permeability in umbilical vein endothelial cells. Glutamine regulates the expression of inflammatory cytokines and maintains the balance of the mitochondria in a cytoprotective manner. .

Glutamina: su papel en el paciente crítico / Glutamine: the role in critically ill patients

La glutamina es un aminoácido condicionalmente esencial considerado actualmente como un importante fármaco-nutriente. Niveles plasmáticos bajos de glutamina han demostrado comportarse como un factor independiente de mortalidad en el paciente crítico, y su adición al soporte nutricional ha probado disminuir las complicaciones infecciosas, la mortalidad y la estancia hospitalaria. En los últimos años han aparecido nuevos estudios que indicanla necesidad de individualizar la vía de acceso y la dosis y el período de suplementación para determinados grupos de pacientes candidatos a la suplementación con glutamina, y por otra parte, a tenor de los resultados, es aconsejable evitarla en situaciones deshock hipovolémico inestable, fallo multiorgánico o insu¬ciência renal no sometida a técnicas de depuración.

Glutamine is a conditionally essential aminoacid which is nowadays considered an important pharmaco nutrient. Low serum levels of glutamine have proven to be an independent predictor of mortality in the critically ill patient. Supplementation with glutamine as a part of a nutritional therapy has demonstrated to reduce infectious complications, length of stay in hospital and mortality. Recent new published data show the need to individualize the route, dose, length of supplementation for determined groups of candidate patients to glutamine administration. On the other hand, according to results, glutamine is not recommended in case of unstable hypovolemic shock, multiorgan faillure, or renal failure not subjected to depuration techniques.

Effect of carbon and nitrogen sources on in vitro flower and fruit formation and withanolides production in Withania somnifera (L.) Dunal.

We studied the influence of sucrose and nitrogen concentration on in vitro flowering and fruit setting in elongated shoots of Withania somnifera. BA (1.5 mg/l) and IAA (0.3 mg/l) on MS medium supplemented with 4% sucrose showed 67% of in vitro flower induction frequency, 9 flowers/shoot, 4 fruits/shoot and 11 seeds/fruit in elongated-shoots. Different concentrations of nitrogen sources (L-glutamine, adenine sulphate, ammonium nitrate, potassium nitrate and sodium nitrate 5-25 mg/l) were tested in combination with 4% sucrose and BA at 1.5 mg/l and IAA at 0.3 mg/l. Highest number of flowers (20 flowers/shoot; 2.2-fold) and fruits (16 fruits/shoot; 3.39-fold), fruit setting (12 seeds/fruit; 1.08-fold) at a higher frequency (88 %) were achieved on MS medium augmented with 15 mg/l adenine sulphate with same PGRs and sucrose concentration. The maximum production of withanolide A (0.68 mg/g DW) and withanolide B (0.77 mg/g DW) was recorded in in vitro fruits. Highest accumulation of withaferin A (2 mg/g DW) was quantified from in vitro flowers, whereas, it was low in in vitro fruits (0.49 mg/g DW withaferin A). However, withanone (0.23 mg/g DW) was found accumulated uniformly in both in vitro flowers and fruits compared to control.

Effect of glutamine supplementation on left colon healing in rats with extrahepatic biliary obstruction

PURPOSE: To evaluate the influence of glutamine and obstructive jaundice on left colon healing in rats. METHODS: Sixteen male rats were allocated across four groups: LG - Common bile duct ligation followed by colotomy and bowel suture on postoperative day 7. Supplementation with glutamine 2% from day 4 after duct ligation until euthanasia. L - Common bile duct ligation followed by colotomy and bowel suture on postoperative day 7. No glutamine supplementation. M - Common bile duct manipulation followed by colotomy and bowel suture on postoperative day 7. No glutamine supplementation. MG - Common bile duct manipulation followed by colotomy and bowel suture on postoperative day 7. Supplementation with glutamine 2% from day 4 after duct manipulation until euthanasia. On the day of euthanasia, bursting pressure of the sutured bowel segment was measured and samples were collected for histopathological analysis. RESULTS: There were no differences in bursting pressure among groups : LG vs. M (110 ± 28 vs. 173 ± 12; p = 0.08). Groups L and MG were not different from group M (156 ± 12 and 118 ± 22. Glutamine supplementation was associated with less edema, polymorphonuclear lymphocyte infiltration, bacterial colonies, and abscess formation, as well as with increased collagen formation. CONCLUSION: Obstructive jaundice had no negative effect and glutamine supplementation had no positive effect on colonic scar strength in rats. .

Análise da ação do gel de plaquetas e glutamina em mucosite causada por quimioterapia induzida em ratos Wistar / Analysis of Platelet Gel Action and Glutamine in Mucositis caused by chemotherapy induced in Wistar Rats

Neste estudo avaliou-se a ação do gel de Plaquetas e da Glutamina no processo de cicatrização de lesões bucais causadas por mucosite induzida por quimioterapia em ratos Wistar. Foram utilizados 50 animais divididos em 05 grupos: um Grupo A (Gel de Plaquetas), Grupo B (Glutamina tópica), Grupo C (Glutamina gavagem), Grupo D (Glutamina + Gel de plaquetas) e Grupo E (controle +). A partir do 7o dia após a quimioterapia, avaliou-se os graus de mucosite e iniciou-se a aplicação dos medicamentos propostos para cada grupo. O sacrifício dos animais ocorreu em 5 e 10 dias após o início de aplicação dos medicamentos. Foram realizadas as biópsias da mucosa jugal e língua para análise do exame histopatológico onde se avaliou a quantidade de macrófagos, linfócitos e queratinização. Os graus de mucosite desenvolvidos na 1a e 2a fase do experimento apresentaram variação numérica importante, mas sem diferenças estatísticas significantes. Na análise histológica, resultados estatisticamente significativos foram obtidos (Fase 1) para linfócitos em mucosa jugal, onde o grupo B (glutamina) foi maior que o do grupo D (gel de plaquetas + glutamina) (p = 0,032); os linfócitos em língua do grupo A (gel de plaquetas) (p = 0,000) foi superior quando comparado com todos os outros grupos. A queratinização em mucosa jugal no grupo D (Fase 1) apresentou resultados significativamente superiores quando comparada com a queratinização dos demais grupos. A queratinização em língua no grupo D apresentou diferenças estatisticamente significantes (p = 0,000) e maior em relação aos outros grupos. Na fase 2, os macrófagos em língua tiveram resultados significantes entre os grupos A e C (p = 0,031) e A e E (p = 0,006), onde A foi maior. Diante dos resultados encontrados, concluiu-se que os biocurativos utilizados neste estudo promoveram uma maior reação inflamatória no conjuntivo e maior queratinização no epitélio. Entretanto, clinicamente, nas lesões observadas, o tempo de cicatrização foi...

Among bio-curatives there are those derived from the addition "in vitro" of thrombin and calcium gluconate to the platelet rich human plasma that stimulate its degranulation to releasing of growth factors acting on the healing process. Glutamine is the amino acid present in plasma and muscle tissue being considered an important energetic source for the immune system cells. Mucositis is a denomination for the changes that occur in the oral mucosa, mainly due to the cancer treatments. In this study, the action of platelet gel and Glutamine was evaluated in the oral lesions healing process caused by mucositis induced by chemotherapy in Wistar rats. 50 animals divided into 05 groups were used: A Group (Platelet Gel), B Group (Topical glutamine), C Group (Glutamine gavage), D Group (Glutamine + Platelet Gel) and E Group (control +). From the 7th day after chemotherapy, the degree of mucositis was evaluated and the proposed drug application began for each group. The animal sacrifice occurred within 5 to 10 days after the medicine application beginning. Jugal and tongue mucosa biopsies for histopathological examination analysis were carried out which evaluated the macrophages amount, lymphocytes and keratinization. The mucositis degrees developed in the 1st and 2nd phase of the experiment showed important numerical variation, but without meaningful statistical differences. In the histological analysis, statistically meaningful results were obtained (Phase 1) for lymphocytes in the jugal mucosa where the B group (glutamine) was higher than D group (platelet gel + glutamine) (p = 0,032); lymphocytes in tongue in A group (platelet gel) (p = 0,000) was higher when compared to all other groups. Keratinization in the jugal mucosa in D group (Phase 1), showed meaningfully superior results when compared to the keratinization of the other groups. The Keratinization in tongue in D group showed meaningful statistical differences (p = 0,000) and higher compared to the other...

Análise da ação do gel de plaquetas e glutamina em mucosite causada por quimioterapia induzida em ratos Wistar / Analysis of Platelet Gel Action and Glutamine in Mucositis caused by chemotherapy induced in Wistar Rats

Neste estudo avaliou-se a ação do gel de Plaquetas e da Glutamina no processo de cicatrização de lesões bucais causadas por mucosite induzida por quimioterapia em ratos Wistar. Foram utilizados 50 animais divididos em 05 grupos: um Grupo A (Gel de Plaquetas), Grupo B (Glutamina tópica), Grupo C (Glutamina gavagem), Grupo D (Glutamina + Gel de plaquetas) e Grupo E (controle +). A partir do 7o dia após a quimioterapia, avaliou-se os graus de mucosite e iniciou-se a aplicação dos medicamentos propostos para cada grupo. O sacrifício dos animais ocorreu em 5 e 10 dias após o início de aplicação dos medicamentos. Foram realizadas as biópsias da mucosa jugal e língua para análise do exame histopatológico onde se avaliou a quantidade de macrófagos, linfócitos e queratinização. Os graus de mucosite desenvolvidos na 1a e 2a fase do experimento apresentaram variação numérica importante, mas sem diferenças estatísticas significantes. Na análise histológica, resultados estatisticamente significativos foram obtidos (Fase 1) para linfócitos em mucosa jugal, onde o grupo B (glutamina) foi maior que o do grupo D (gel de plaquetas + glutamina) (p = 0,032); os linfócitos em língua do grupo A (gel de plaquetas) (p = 0,000) foi superior quando comparado com todos os outros grupos. A queratinização em mucosa jugal no grupo D (Fase 1) apresentou resultados significativamente superiores quando comparada com a queratinização dos demais grupos. A queratinização em língua no grupo D apresentou diferenças estatisticamente significantes (p = 0,000) e maior em relação aos outros grupos. Na fase 2, os macrófagos em língua tiveram resultados significantes entre os grupos A e C (p = 0,031) e A e E (p = 0,006), onde A foi maior. Diante dos resultados encontrados, concluiu-se que os biocurativos utilizados neste estudo promoveram uma maior reação inflamatória no conjuntivo e maior queratinização no epitélio. Entretanto, clinicamente, nas lesões observadas, o tempo de cicatrização foi...

Among bio-curatives there are those derived from the addition "in vitro" of thrombin and calcium gluconate to the platelet rich human plasma that stimulate its degranulation to releasing of growth factors acting on the healing process. Glutamine is the amino acid present in plasma and muscle tissue being considered an important energetic source for the immune system cells. Mucositis is a denomination for the changes that occur in the oral mucosa, mainly due to the cancer treatments. In this study, the action of platelet gel and Glutamine was evaluated in the oral lesions healing process caused by mucositis induced by chemotherapy in Wistar rats. 50 animals divided into 05 groups were used: A Group (Platelet Gel), B Group (Topical glutamine), C Group (Glutamine gavage), D Group (Glutamine + Platelet Gel) and E Group (control +). From the 7th day after chemotherapy, the degree of mucositis was evaluated and the proposed drug application began for each group. The animal sacrifice occurred within 5 to 10 days after the medicine application beginning. Jugal and tongue mucosa biopsies for histopathological examination analysis were carried out which evaluated the macrophages amount, lymphocytes and keratinization. The mucositis degrees developed in the 1st and 2nd phase of the experiment showed important numerical variation, but without meaningful statistical differences. In the histological analysis, statistically meaningful results were obtained (Phase 1) for lymphocytes in the jugal mucosa where the B group (glutamine) was higher than D group (platelet gel + glutamine) (p = 0,032); lymphocytes in tongue in A group (platelet gel) (p = 0,000) was higher when compared to all other groups. Keratinization in the jugal mucosa in D group (Phase 1), showed meaningfully superior results when compared to the keratinization of the other groups. The Keratinization in tongue in D group showed meaningful statistical differences (p = 0,000) and higher compared to the other...

Glutamine and ornithine alpha-ketoglutarate supplementation on malate dehydrogenases expression in hepatectomized rats

PURPOSE: To evaluate the relative gene expression (RGE) of cytosolic (MDH1) and mitochondrial (MDH2) malate dehydrogenases enzymes in partially hepatectomized rats after glutamine (GLN) or ornithine alpha-ketoglutarate (OKG) suplementation. METHODS: One-hundred and eight male Wistar rats were randomly distributed into six groups (n=18): CCaL, GLNL and OKGL and fed calcium caseinate (CCa), GLN and OKG, 0.5g/Kg by gavage, 30 minutes before laparotomy. CCaH, GLNH and OKGH groups were likewise fed 30 minutes before 70% partial hepatectomy. Blood and liver samples were collected three, seven and 14 days after laparotomy/hepatectomy for quantification of MDH1/MDH2 enzymes using the real-time polymerase chain reaction (PCR) methodology. Relative enzymes expression was calculated by the 2-ΔΔC T method using the threshold cycle (CT) value for normalization. RESULTS: MDH1/MDH2 RGE was not different in hepatectomized rats treated with OKG compared to rats treated with CCa. However, MDH1/MDH2 RGE was greater on days 3 (321:1/26.48:1) and 7 (2.12:1/2.48:1) while MDH2 RGE was greater on day 14 (7.79:1) in hepatectomized rats treated with GLN compared to control animals. CONCLUSION: Glutamine has beneficial effects in liver regeneration in rats by promoting an up-regulation of the MDH1 and MDH2 relative gene expression. .

Liver regeneration with l-glutamine supplemented diet: experimental study in rats / Avaliação da regeneração hepática com dieta suplementada com l-glutamina: estudo experimental em ratos

OBJECTIVE: To assess liver regeneration in rats after 60% hepatectomy with and without supplementation of L-glutamine through liver weight changes, laboratory parameters and histological study. METHODS: 36 male rats were divided into two groups: glutamine group and control group. Each group was subdivided into three subgroups, with death in 24h, 72h and seven days. The glutamine group received water and standard diet supplemented with L-glutamine, and the control recieved 0.9% saline. In all subgroups analysis of liver regeneration was made by the Kwon formula, study of liver function (AST, ALT, GGT, total bilirubin, indirect and indirect bilirubin and albumin) and analysis of cell mitosis by hematoxylin-eosin. RESULTS: In both groups there was liver regeneration by weight gain. Gamma-GT increased significantly in the control group (p < 0.05); albumin increased in the glutamine group. The other indicators of liver function showed no significant differences. Histological analysis at 72h showed a higher number of mitoses in the glutamine group, with no differences in other subgroups. CONCLUSION: Diet supplementation with L glutamine is beneficial for liver regeneration. .

OBJETIVO: Avaliar a regeneração hepática em ratos submetidos à hepatectomia de 60% com e sem suplementação de L-glutamina através de alteração ponderal do fígado, parâmetros laboratoriais e estudo histológico. MÉTODOS: Foram usados 36 ratos machos, distribuídos em dois grupos: grupo controle e grupo glutamina. Cada um foi subdividido em mais três subgrupos com óbito em 24h, 72h e sete dias. O grupo glutamina recebeu água e dieta padrão suplementada com L-glutamina e o controle solução fisiológica a 0,9%. Em todos os subgrupos foi feita análise da regeneração hepática através da fórmula de Kwon, estudo da função hepática (AST, ALT, gama GT, bilirrubina total, bilirrubina indireta e indireta e albumina) e análise de mitose celular pela coloração de Hematoxilina - Eosina. RESULTADOS: Nos dois grupos houve regeneração hepática pelo ganho ponderal. Gama GT aumentou significativamente no grupo controle (p<0,05) já albumina aumentou no da glutamina. Os demais indicadores da função hepática não apresentaram diferenças significantes. A análise histológica em 72h mostrou maior número de mitoses no grupo glutamina, não havendo diferença nos demais subgrupos. CONCLUSÃO: A suplementação de L-glutamina à dieta é benéfica para a regeneração hepática. .

Efeito radioprotetor da L-Glutamina na parede da bexiga de ratos submetidos à irradiação pélvica / Protective effects of L-Glutamine on the bladder wall of rats submitted to pelvic radiation

A radioterapia é frequentemente utilizada no tratamento de tumores da próstata, porém durante esse procedimento a bexiga sadia usualmente sofre efeitos colaterais. Através do uso de um modelo animal para irradiação pélvica, avaliamos se a suplementação nutricional com L-glutamina poderia prevenir possíveis danos na parede da bexiga, especialmente em suas camadas mais superficiais. Ratos Wistar adultos machos com idade entre 3 e 4 meses foram separados em grupos de 8 animais: grupo controle que não recebeu a irradiação; grupos somente irradiados que foram mortos 7 (R7) e 15 dias (R15) após a irradiação (dose única de 10 Gy na região pélvico-abdominal); grupos irradiados e suplementados com L-glutamina (0,65g/kg de peso por dia), que foram mortos 7 (RG7) ou 15 após a irradiação. Células e vasos sanguíneos da lâmina própria, bem como o urotélio, foram avaliados com métodos histológicos. No urotélio foram feitas análises da altura e densidade nuclear e na lâmina própria densidade celular, densidade vascular e o número de mastócitos. Os resultados mostraram que em R7, a altura e densidade nuclear do urotélio e a densidade celular da lâmina própria não foram alterados significativamente. Entretanto a densidade dos vasos sanguíneos foi reduzida em 48% (p<0,05) e essa alteração foi evitada pela glutamina (p <0,02). No grupo R15, a densidade celular do epitélio aumentou em 35% (p<0,02). A densidade celular da lâmina própria não apresentou diferença estatística entre os grupos. Os mastócitos na lâmina própria foram reduzidos em R7 e R15. Apesar de ainda reduzidos em RG7 em RG15 houve aumento no número desse tipo celular o que sugere uma ação positiva da glutamina. Células α-actina positivas na lâmina própria formam uma camada suburotelial e foram identificadas como miofibroblastos. A espessura dessa camada aumentou em R7, mas foi semelhante ao controle em RG7, enquanto alterações em R15 e RG15 foram menos evidentes. Esses resultados mostraram que a utilização ...

Radiotherapy is often used to treat prostate tumors, but the normal bladder is usually adversely affected. Using an animal model of pelvic radiation, we investigated whether glutamine nutritional supplementation can prevent radiation-induced damage to the bladder, especially in its more superficial layers. Male rats aged 3 to 4 months were divided into groups of 8 animals each: controls, which consisted intact animals; radiated-only rats, which were sacrificed 7 (R7) or 15 (R15) days after a radiation session (10 Gy aimed at the pelvico-abdominal region); and radiated rats receiving L-glutamine supplementation (0.65 g/kg body weight/day), which were sacrificed 7 (RG7) or 15 (RG15) days after the radiation session. Morphological and morphometric analysis of the urothelium were made. Nuclear density, lamina propria cell density and mast cells numbers per area were counted. The results showed that, in R7, epithelial thickness, epithelial cell density, and cell density in the lamina propria were not significantly affected. However, density of blood vessels in R7 was reduced by 48% (p < 0.05) and this alteration was mostly prevented by glutamine (p < 0.02). In R15, density of blood vessels in the lamina propria was not significantly modified. However, epithelial thickness was reduced by 25% (p < 0.05) in R15, and this effect was prevented by glutamine (p < 0.01). In R15, epithelial cell density was increased by 35% (p < 0.02), but glutamine did not protect against this radiation-induced increase. Cell density in the lamina propria was likewise unaffected in R15. Density of mast cells in the lamina propria was markedly reduced in R7 and R15. The density was still reduced in RG7, but a higher density in RG15 suggested a glutamine-mediated recovery. Alpha-actin positive cells in the lamina propria formed a suburothelial layer and were identified as myofibroblasts. Thickness of this layer was increased in R7, but was similar to controls in RG7, while changes in R15 ...

Modulation of murine blastocyst hatching in vitro by glutamine and tryptophan

Enrichment of culture media with amino acids improves embryo development. However, little is known about the specific action of each amino acid during embryogenesis. The present study was undertaken to examine the effect of L-glutamine (Gln) and tryptophan (Trp) on mouse embryo hatching, expansion and viability in vitro. Blastocysts were collected from 6- to 8-week-old female BALB/c mice (N = 30) and cultured in M2 medium containing either 0.125, 0.25 or 0.5 mM Trp, 1 mM Gln, or M2 alone. Gln significantly increased (100 percent; P < 0.05) blastocyst hatching at 24 h compared to M2 alone or Trp; moreover, Trp inhibited blastocyst hatching when compared to M2 alone (P < 0.05) at 72 h. In contrast, the percentage of embryos reaching the state of expanded blastocyst at 48 h was significantly higher in medium with 1 mM Gln (66.6 percent; P < 0.05) or with 0.125 mM Trp (61.1 percent; P < 0.05). Unexpectedly, Trp increased the percentage of degenerated blastocysts after 48 h (67.7 percent; P < 0.05), while Gln preserved blastocyst viability. These results suggest that Gln may enhance blastocyst hatching, expansion and viability in vitro.

Effect of glutamine on the mRNA level of key enzymes of malate-aspartate shuttle in the rat intestine subjected to ischemia reperfusion / Efeito da glutamina sobre o nível de RNA Mensageiro das enzimas-chave do ciclo malato-aspartato no intestino de ratos submetidos à isquemia e reperfusão

PURPOSE: To determine the effects of oral L-glutamine (L-Gln) and the dipeptide l-alanyl-glutamine (L-Ala-Gln) upon the activity of the malate-aspartate shuttle in the rat distal small intestine following ischemia and reperfusion. METHODS: Seventy-two Wistar rats (350-400g), were randomized in 2 groups (n = 36): group S (Sham) and Group T (Treatment) and divided into 12 subgroups (n = 6): A-A6, and B1-B6. The subgroups A1-A3 were subjected to sham procedures at 30 and 60 minutes. Thirty minutes before the study, rats were treated with calcium caseinate, 0.5g/Kg (subgroups A1, A4, B1, B4), L-Gln, 0.5g / kg (subgroups A2, A5, B2 and B5) or L-Ala-Gln, 0.75g/Kg (subgroups A3, A6, B3, B6), administered by gavage. Ischemia was achieved by clamping the mesenteric vessels, delimiting a segment of bowel 5 cm long and 5 cm apart from the ileocecal valve. Samples were collected 30 and 60 minutes after start of the study for real-time PCR assay of malate dehydrogenases (MDH1-2) and aspartate-aminotransferases (GOT1-2) enzymes. RESULTS: Tissue MDH and GOT mRNA expression in intestinal samples from rats preconditioned with either L-Gln or L-Ala-Gln showed no significant differences both during ischemia and early reperfusion. CONCLUSION: Activation of the malate-aspartate shuttle system appears not to be the mechanism of glutamine-mediated elevation of glucose oxidation in rat intestine during ischemia/reperfusion injury.

OBJETIVO: Determinar os efeitos da administração oral de L-glutamina (L-Gln) e do dipeptídeo L-alanil-glutamina (L-Ala-Gln) sobre a atividade do ciclo malato-aspartato no intestino delgado distal de ratos após isquemia/reperfusão. MÉTODOS: Setenta e dois ratos Wistar (350-400g) foram randomizados em 2 grupos (n = 36): T grupo S (Sham) e grupo (Tratamento) e distribuídos em 12 subgrupos (n = 6): A-A6, e B1-B6. Os subgrupos A1-A3 foram submetidos a procedimentos "sham" aos 30 e 60 minutos. Trinta minutos antes do estudo, os ratos foram tratados com caseinato de cálcio, 0,5 g/kg (subgrupos A1, A4, B1 e B4), L-Gln, 0,5 g/kg (subgrupos A2, A5, B2 e B5) ou L-Ala -Gln, 0,75g/kg (subgrupos A3, A6, B3, B6), administrado por gavagem. A isquemia foi obtida por pinçamento dos vasos mesentéricos, delimitando um segmento do intestino cinco centímetros de comprimento e 5 cm da válvula ileocecal. Amostras foram coletadas aos 30-60 minutos para ensaio de PCR em tempo real das enzimas malato desidrogenases (MDH1-2), aspartato-aminotransferase (GOT1-2). RESULTADOS: A expressão de MDH e GOT mRNA nas amostras provenientes do intestino delgado de ratos pré-condicionados com L-Gln ou L-Ala-Gln não apresentou diferenças significativas, tanto durante a isquemia como na fase inicial de reperfusão. CONCLUSÃO: Ativação do ciclo malato-aspartato não parece ser o mecanismo de elevação glutamina-mediada da oxidação da glicose no intestino de ratos durante a isquemia / reperfusão.

Preoperative glutamine infusion improves glycemia in heart surgery patients / Infusão pré-operatória de glutamina melhora a glicemia em pacientes submetidos à cirurgia cardíaca

PURPOSE: To evaluate the effects of pre-operative L-alanyl-glutamine (L-Ala-Gln) on blood glucose control in patients with coronary obstruction, selected for myocardial revascularization. METHODS: Twenty-two patients (63±8 years) were randomly assigned to receive 250ml of L-Ala-Gln 20 percent plus saline 750 ml (Group L- Ala-Gln, n=11) or saline 1000 ml (Group Saline, n=11) over 3 hours before operation. Pre-operative blood samples were collected 3h before (T-1) and at the beginning of the surgical procedure (T-2). Intra-operative samples were collected immediately before the start (T-3) and the end of extra-corporeal perfusion (T- 4). Post-operative samples were collected 12h (T-12) and 24h later (T-24). RESULTS: Glycemia decreased significantly in L-Ala-Gln treated patients during the intraoperative period. The same effect did not occur in saline patients. As the rate of insulin infusion, administered routinely to patients undergoing surgery with extracorporeal circulation was constant in both groups during surgery, the reduction of blood glucose in group L-Ala-Gln does not seem to be related to exogenous insulin. CONCLUSION: Pre-operative use of L-Ala-Gln improves glycemic control in patients with coronary artery occlusion, submitted to myocardial revascularization.

OBJETIVO: Avaliar os efeitos do uso pré-operatório da L-alanil-glutamina (L-Ala-Gln) no controle glicêmico em pacientes, selecionados para a revascularização do miocárdio. MÉTODOS: Vinte e dois pacientes cardiopatas (63±8 anos) foram randomizados para receber 250 ml de L-Ala-Gln 20 por cento em 750 ml de solução salina (Grupo L-Ala-Gln, n=11) ou soro fisiológico 1000 ml (Grupo Salina, n=11). Amostras de sangue foram coletadas no pré-operatório, três horas antes (T-1: basal) e no início do procedimento cirúrgico (T-2); imediatamente antes do início (T-3) e no final da perfusão extra-corpórea (T-4); 12h (T-12) e 24h após a conclusão do procedimento. As infusões, com duração de 3 horas, foram iniciadas 3 h antes do procedimento operatório. RESULTADOS: Houve redução significativa da glicemia nos pacientes tratados com L-Ala-Gln durante o período intra-operatório (T-3 e T-4). O mesmo efeito não ocorreu nos pacientes do grupo salina. Como a taxa de infusão de insulina, administrada rotineiramente aos pacientes submetidos à cirurgia com circulação extracorpórea, foi constante em ambos os grupos durante o período intra-operatório, a redução da glicemia no grupo L-Ala-Gln não parece estar relacionada à insulina exógena. CONCLUSÃO: O uso pré-operatório de L-Ala-Gln melhora o controle glicêmico em pacientes com obstrução coronariana, submetidos à revascularização miocárdica.

effects of combined use of glutamine and growth hormone on the bacterial translocation associated with obstructive jaundice

To investigate the effects of combined use of glutamine and growth hormone on bacterial translocation. The study was performed at the laboratories of the Department of Physiology at Ataturk University Medical School, Erzurum, Turkey between June and September 2007. Forty rats divided into 5 groups of 8, were included in the study. In the study groups, the common bile duct was ligated to obtain obstructive jaundice. The rats in the control group CG were given sodium chloride, in the glutamine group GLG they were given glutamine, in the growth hormone group GHG, growth hormone, and in the glutamine + growth hormone group GLGHG glutamine + growth hormone at equal doses by the same methods. Blood, spleen, liver, lymph node, and cecal content samples were obtained. Total bilirubin TB, alkaline phosphates ALP, and gamma glutamine transferase GGT activities were evaluated. In the CG, cecal contents were higher than in the GLG, and cecal contents and BT were higher than in the GHG and the GLGHG. The BT rate was the lowest in the GLGHG, with a borderline difference with the values of the GLG and GHG. We found that in preventing BT, combined use of glutamine, and growth hormone was more effective than using each of these agents alone

Reversible male sterility in transgenic tobacco carrying a dominant-negative mutated glutamine synthetase gene under the control of microspore-specific promoter.

Metabolic engineering was used to disrupt glutamine metabolism in microspores in order to block pollen development. We used a dominant-negative mutant (DNM) approach of cytosolic glutamine synthetase (GS1) gene under the microspore-specific promoter NTM19 to block glutamine synthesis in developing pollen grains. We observed partial male sterility in primary transgenic plants by using light microscopy, FDA, DAPI and in vitro pollen germination test. Microspores started to die in the early unicellular microspore stage, pollen viability in all primary transgenic lines ranged from 40-50%. All primary transgenics produced seeds like control plants, hence the inserted gene did not affect the sporophyte and was inherited through the female germline. We regenerated plants by in vitro microspore embryogenesis from 4 individual lines, pollen viability of progeny ranged from 12 to 20%, but some of them also showed 100% male sterility. After foliage spray with glutamine, 100% male-sterile plants were produced viable pollen and seed set was also observed. These results suggested that mutated GS1 activity on microspores had a significant effect on normal pollen development. Back-cross progenies (T2) of DH 100% male-sterile plants showed normal seed set like primary transgenics and control plants.

Intestinal intraluminal injection of glutamine increases trolox total equivalent antioxidant capacity (TEAC) in hepatic ischemia-reperfusion

PURPOSE: To evaluate the effects of intraluminal injection of glutamine on the serum trolox equivalent antioxidant capacity in an experimental model of ischemia-reperfusion of the liver observing the applicability of modifications on the original assay method. METHODS: Thirty Wistar rats underwent laparotomy to perform a 20 cm blind sac of small bowel and occlusion of the hepatic hilo for 30 minutes and reperfusion for 5 minutes. Into the gut sac it was injected glutamine (glutamine group, n=10) or distilled water (control group, n=10). Ten other animals (sham group) underwent laparotomy without artery occlusion. Blood samples were collected for trolox equivalent antioxidant capacity assays in different temperature conditions, reagent quantities and time for spectrophotometer readings. RESULTS: Total antioxidant capacity was significantly greater in glutamine group than in both control group (1,60[1,55-1,77] vs 1,44[1,27-1,53]) and sham group (1,60[1,55-1,77] vs 1,48[1,45-1,59]). CONCLUSION: Glutamine enhanced serum antioxidant capacity. The assay technique consistently reflected the changes in the antioxidant defenses in this experimental model.

OBJETIVO: Avaliar em um modelo experimental de isquemia-reperfusão hepática os efeitos da injeção intraluminal de glutamina na capacidade anti-oxidante total em equivalência ao trolox (TEAC) do plasma, verificando a aplicabilidade de modificações ao método original de dosagem. MÉTODOS: Trinta ratos Wistar foram submetidos a laparotomia e confecção de uma alça fechada de 20 cm de comprimento envolvendo o intestinal delgado distal seguido do clampeamento do hilo hepático por 30 minutos e reperfusão por 5 minutos. Na alça fechada foi injetada glutamina (grupo glutamina; n=10) ou água destilada (grupo controle; n=10). Em dez animais (grupo sham) não foi realizado clampeamento hilar. Coletou-se sangue para dosagem da capacidade antioxidante total em equivalência ao trolox em condições modificadas de temperatura, proporções relativas dos reagentes e tempo de leitura sob espectrofotometria. RESULTADOS: A capacidade antioxidante total foi significantemente maior (p<0.05) no grupo glutamina que no grupo controle (1,60[1,55-1,77] vs 1,44[1,27-1,53]) e grupo sham (1,60[1,55-1,77] vs 1,48[1,45-1,59]). Não houve diferenças estatísticas entre o grupo controle e o grupo sham. CONCLUSÃO: A glutamina melhorou a capacidade anti-oxidante total plasmática. O método de dosagem refletiu consistentemente alterações na defesa anti-oxidante nesse modelo experimental.

Effects of the combined use of glutamine and growth hormone in the intestinal adaptation after massive resection of the small bowel in rats

OBJETIVO: Investigar os efeitos do uso combinado da glutamina (GL) e do hormônio do crescimento (GH) no intestino de ratos submetidos a ressecção de 80% do intestino delgado. MÉTODOS: Vinte e quatro ratos Wistar foram randomizados para receber uma a dieta padrão- grupo controle (GC, n=12) ou a mesma dieta adicionada de glutamina 4% (isocalórica, isoproteica) - grupo glutamina- hormônio do crescimento (GL-GH, n=12) após a enterectomia à 80%. Este último grupo recebeu por via sub-cutânea, 0,6 UI/dia de GH. Grupos de seis ratos cada foram sacrificados no 5º e 14º dias. As seguintes variáveis foram estudadas: peso corporal, peso de mucosa, histomorfometria e conteúdo de DNA no segmento ressecado inicialmente e no intestino adaptado coletado após o sacrifício. RESULTADOS: Todos os animais perderam peso até o 5º dia, estabilizando-se após esta data em ambos os grupos. Não houve diferença estatística no peso da mucosa associada a grupos ou datas. O peso da mucosa do íleo diminuiu dos dados iniciais para os finais, quando comparados a mucosa jejunal (p<0.02). O conteúdo de DNA aumentou dos dados iniciais para os finais (p=0.001) em ambos os grupos, porém, o aumento foi maior nos animais do grupo GL-GH (CG = 0.53 [95% CI, 0.44-0.62] g/cm-1 vs. GL-GH= 0.85 [95%CI, 0.76-0.94] g/cm-1; p<0.01), especialmente no 14º dia. O conteúdo de DNA no íleo foi significativamente maior que no jejuno (p=0.01). Houve um aumento significativo na espessura da parede e na profundidade da cripta, no grupo controle (p<0.01). CONCLUSÃO: A adaptação intestinal após ressecção extensa é melhorada com o uso combinado de glutamina e GH.

Effect of Glutamine on the Non-steroidal Anti-inflammatory Drug-induced Bacterial Translocation / 대한소화기학회지

BACKGROUND/AIMS: NSAIDs induce gut damage throughout the entire gastrointestinal tract and bacterial translocation. The aim of this study was to examine if administration of glutamine was able to prevent the NSAID-induced gut damages and bacterial translocation in the animal models. METHODS: Rats were utilized into 5 groups; control group, diclofenac group, and diclofenac with glutamine 0.8, 1.6, and 3.2 g/kg/day group. The animals with glutamine were fed with L-glutamine for 4 days before diclofenac administration. Gut injury was induced by administration of a single dose of diclofenac (80 mg/kg orally). Intestinal permeability (24 hour urinary excretion of phenolsulfonphthalein), enteric aerobic bacterial counts, serum biochemical profiles and bacterial translocation to mesenteric lymph nodes, liver and spleen were measured. RESULTS: Diclofenac caused the increase in intestinal permeability, enteric bacterial count, enteric protein and albumin loss and bacterial translocation. Administration of glutamine reduced the increase in intestinal permeability, protein losing enteropathy, enteric bacterial overgrowth and bacterial translocation induced by diclofenac. CONCLUSIONS: Glutamine may have beneficial effects on NSAID-induced gut damage and bacterial translocation.

Combined Administration of Glutamine and Growth Hormone Synergistically Reduces Bacterial Translocation in Sepsis

We investigated the combined effect of glutamine (GLN) and growth hormone (GH) on bacterial translocation (BT) in sepsis. After single intraperitoneal injection of lipopolysaccharide (10 mg/kg), 48 rats were divided randomly into four groups of 12 animals each: the control group received chow orally; the GLN group received chow plus 10% GLN; GH group received chow plus GH; and the GLN/GH group received chow, 10% GLN, and GH. Twenty-four and 96 hr later, rats were sacrificed. Portal blood culture, bacterial colony counts of cultured mesenteric lymph nodes, mucosal thickness, malondialdehyde (MDA), and glutathione (GSH) levels in the gut mucosa were measured. There was no significant change of the rate of portal blood culture between all treatment groups at 24 and 96 hr. At 24 hr, the rats receiving combined treatment of GLN and GH showed lower bacterial colony counts and mucosal MDA levels than the control rats, and higher mucosal GSH levels than the control and GLN-treated rats. At 96 hr, rats treated with both GLN and GH exhibited lower bacterial colony counts and mucosal MDA levels, and higher mucosal thickness and GSH levels than control, GLN, or GH-treated rats. This study suggests that the combination of GLN and GH may synergistically reduce BT over time in sepsis.