Objective To investigate the effect of recombinant human erythropoietin (rhEPO) on the expression of glutamine synthetase (GS) of cultured rat retinal Müller cells in high glucose environment in vitro. Methods Müller cells were isolated from retinas of 10 Sprague-Dawley rats at postnatal day three to five by trypsin digestion, and were randomly divided into six groups, including normal control group, high glucose group, high glucose +5 U/ml rhEPO group, high glucose+10 U/ml rhEPO group, high glucose +20 U/ml rhEPO group, high glucose+40 U/ml rhEPO groups. After 48 hours, the apoptosis of retinal Müller cells were assayed by terminal transferase-mediated DNA end labelling assay, and the expression levels of GS protein were detected with semi-quantitative immunocytochemistry. Results Compared with the normal control group, the cell viability and GS protein were reduced while the cell death increased in Müller cells cultured in high glucose, the difference was statistically significant (t=27.4,P＜0.01). Compared with the high glucose group, rhEPO treatment reduced the apoptotic Müller cells (t=857.2, 2 374.6, 2 473.2, 2 537.7;P＜0.01), induced the expression of GS proteins (t=3.2, 18.0, 22.5, 26.4; P＜0.05). Conclusions rhEPO can protect Müller cells from apoptosis under high glucose condition. The mechanism may be related to its function to up-regulate the GS protein expression, promote glutamic acid cycle, and reduce the excitotoxicity effects of high concentration of glutamate.
Objective To study the effects of glutaminase (GA) gene blocked by antisense nucleotide on apoptosis of transplanted gastric carcinoma cells in nude mice. Methods The plasmid containing antisense sequence of GA gene was trans-fected into gastric carcinoma cells , then the cells were injected to endermic tissue of nude mice to create animal models of gastric carcinoma. Apoptosis of tumor cells was detected by terminal deoxynucleotidyl transferase2mediated nick end labeling (TUNEL) method. The expression of GA mRNA in tumor tissue was measured by reverse transcription polymerase chain reaction (RT2PCR) technique. Results After the successful transfection of plasmid containing antisense sequence of GA gene into gastric carcinoma cells , the tumor’s growth speed decreased , apoptosis of tumor cells increased , and the expression of GA mRNA also decreased. Conclusion The antisense gene of GA could inhibit the expression of GA gene and significantly increase the apoptosis of gastric carcinoma cells.
Objective To study the effects of two different tidal volume mechanical ventilation on lipopolysaccharide( LPS) -induced acute lung injury( ALI) , and explore the effects of glutamine on ALI.Methods Thirty male Sprague-Dawley rats were randomly divided into three groups. After anesthesia and tracheotomy were performed, the rats were challenged with intratracheal LPS ( 5mg/kg) and received ventilation for 4 hours with small animal ventilator. Group A received conventional tidal volume, while groupB received large tidal volume. Group C received large tidal volume as well, with glutamine injected intravenously 1 hour before ventilation. Arterial blood gases were measured every one hour. 4 hours later, the rats were killed by carotid artery bleeding. The total lung wetweightwas measured and lung coefficient ( total lung wet weight /body weight ×100) was counted. WBCs and neutrophils in BALF were counted. Protein concentration, TNF-α, IL-6, and cytokine-induced neutrophil chemoattractant-1 ( CINC-1) levels in BALF,myeloperoxidase ( MPO) , and superoxide dismutase ( SOD) levels in the lung were assayed respectively.Results PaO2 and SOD levels decreased more significantly in group B than those of group A. The lung coefficient, WBCs, neutrophils, protein, TNF-α, IL-6, and CINC-1 levels in BALF, MPO levels in lung increased more significantly in group B than those of group A. PaO2 and SOD levels were significantly higher in group C than those of group B. The lung coefficient, WBCs, neutrophils, protein, TNF-α, IL-6, and CINC-1 levels in BALF,MPO levels in lung were significantly lower in group C than those of group B. Conclusion Large tidal volume mechanical ventilation aggravates LPS-induced ALI, and glutamine has obviouslyprotective effects.
ObjectiveTo evaluate the effect of glutamineenhanced enteral nutritional support on elder patients after total gastrectomy. MethodsA total of eightyfour cases of elder patients receiving total gastrectomy were included in this study from February 2008 to August 2010. The patients were randomly divided into three groups: glutamineenhanced enteral nutrition (Gln) group, enteral nutrition (EN) group and parenteral nutrition (PN) group. The complications and hospital stay after operation were compared, and the levels of serum total protein, albumin, proalbumin， and transferrin of patients were measured before operation, on 2 d and 10 d after operation, respectively. Furthermore, the percentage of CD4 and CD8 T cells, CD4/CD8 ratio， and the levels of serum IgM and IgG of patients in peripheral blood before and after operation were detected. ResultsNutritional therapy was successfully performed in patients of three groups. The anal exhaust time and hospital stay after operation of patients in Gln group and EN group were significantly lower than those in PN group (Plt;0.05). The difference of postoperative complications and digestive tract symptoms of patients in three groups was not obvious (Plt;0.05). Anastomotic fistula occurred in one patient of PN group on 6 d after operation and was cured by conservative treatment for 54 d. The difference of total protein, albumin, proalbumin, and transferrin levels of patients in three groups before operation was not significant (Pgt;0.05), and these indexes fell dramatically on 2 d after operation and lower than before operation (Plt;0.05), although the intergroup difference was not statistically significant (Pgt;0.05). On 10 d after operation, all indexes recovered in different extent, while those data in Gln group and EN group were significantly higher than those on 2 d after operation (Plt;0.05). The levels of total protein, albumin, and proalbumin of patients in Gln group and EN group were markedly higher than those in PN group (Plt;0.05), although there was no difference between the former groups (Pgt;0.05). The difference of several immunological parameters of patients in three groups before operation was not significant (Pgt;0.05). On 10 d after operation, the percentage of CD4 and CD8 T cells, CD4/CD8 ratio, and the levels of serum IgM and IgG of patients in Gln group returned and even exceeded the preoperative results, which were significantly higher than those in EN group and PN group other than IgM (Plt;0.05). The postoperative results of all parameters except IgG in EN group were significantly lower than preoperative results in patients of EN group and PN group (Plt;0.05). ConclusionsIt is safe and feasible to elder patients who had received total gastrectomy and perioperative glutamine-enhanced nutritional support, which can improve nutrition and immune status, promote the recovery and reduce the duration of hospital stay, and nutritiional support after total gastrectomy is one of the optimal choices for these patients.
【Abstract】 Objective To study the effects of glutamine (Gln) combined with growth hormone （GH） on the levels of cytokine (TNF-α, IL-1, IL-6), coritsol and amino acid metabolism in septic rats. Methods Ten out of 79 SD rats were randomly collected as the control group. Thirty of 69 septic SD rats, which were made by cecal ligation and perforation (CLP) method and were given parenteral nutrition (PN) lived to day 6. They were also randomly divided into three groups as follows: septic group (n=10), parenteral supplemented glutamine group (Gln group, n=10), and Gln combined with GH (Gln+GH group, n=10). On the 6th day, blood drew from portal veins of the dead rats was used to detect the levels of TNF-α， IL-1， IL-6 and cortisol by ELISA. The plasma concentrations of free amino acids were determined by amino acid auto-analyzer. The muscle tissue of extensor digitorum longus was used to determine 3-methyl-histidine (3-MH) by high performance liquid chromatographic (HPLC). Results Except for the control group, most rats developed celiac abscess, hepatic abscess and pulmonary infection. The serum levels of TNF-α, IL-1, IL-6 and cortisol were significantly higher in the septic group than those of the other three groups, and they were significantly lower in the Gln+GH group than those of the Gln group, P＜0.05. Compared with the other three groups, the concentration of total amino acid in the septic group increased more, among which the glutamine and the branched chain amino acids were prominent. Most of concentrations of the amino acids decreased in the Gln group and the Gln+GH group, and the decreased amplitude of the Gln+GH group was larger, P＜0.05, albeit its level of Gln markedly increased. The concentration of 3-MH in muscle tissue was the highest in septic group, and it was significantly higher in the Gln group than that of the Gln+GH group, P＜0.01. ConclusionIt may be necessary to supplement GH combined with Gln as the content of PN to decrease cytokine levels and im-prove amino acid metabolism for septic case.
【Abstract】ObjectiveTo explore the effect of glutamine on immune function of rat with obstructive jaundice and its possible mechanism. MethodsFifty male Wistar rats were randomly divided into three groups: Control group (n=10)， obstructive jaundice group (n=20) and glutamine treatment group (n=20). The serum concentration of TNF-α, IL-10 was detected by using radioimmune method. Liver function was measured through automated biochemistry analyzer. The animal model of obstructive jaundice was established by ligating the rat’s common bile duct. Bacteria cultures were performed with the rat’s tissues of lung, spleen, liver and kidney respectively. ResultsCompared with control group, obstructive jaundice group showed statistically lower serum level of TNF-α, and statistically higher serum level of IL-10, TBIL, ALT and AST during the first and the second week after ligation of common bile duct. During the first and second week after administration of glutamine, the serum TNF-α of glutamine treatment group was statistically higher than that in control group and obstructive jaundice group. Meanwhile, glutamine treatment group showed statistically lower serum level of IL-10, TBIL, ALT and AST than obstructive jaundice group. There were statistically less bacteria translocations in glutamine treatment group than those in obstructive jaundice group. Conclusion Glutamine can increase the immune function by changing serum concentration of TNF-α, IL-10 and decrease the bacteria translocation.
Objective To investigate the joint effects of selective digestive decontamination (SDD) and glutamine (Gln) on preventing intestinal bacterial translocation of orthotopic piggyback liver transplantation and to observe the incidence of postoperative pneumonia in rabbit. Methods Thirty rabbits received orthotopic piggyback liver transplantation and were randomly divided into three groups (SDD group, SDD+Gln group and control group). Mixed emulsion of tobramycin, polymyxin E and nystatin were given to the rabbits in SDD group. Same dosage of the above components plus Gln were given to the rabbits in SDD+Gln group. Samples of portal vein blood, ileum tissue and lung tissue were obtained in each group at different phases during and after operation, the pathological changes of ileum tissue, the bacterial translocation in blood of portal vein and the incidence of postoperative pneumonia were detected. Results The mixing section area of intestinal blood capillaries in SDD+Gln group was smaller compared with control group (P＜0.05， P＜0.01) and SDD group (P＜0.05) while the portal vein was obstructed for 15, 30 and 45 min, and after the operation, respectively. The length of ileum villus in SDD+Gln group was longer than that in control group (P＜0.05) and in SDD group (P＜0.05) before the portal vein was obstructed, but the length of ileum villus in control group gradually became longer and eventually exceeded that in SDD+Gln group at the time of 45 min after the portal vein was obstructed (P＜0.05). After the operation, the length of ileum villus in SDD+Gln group was significantly longer than that in SDD group (P＜0.05) and control group (P＜0.01). At the time of 45 min after the obstruction of portal vein and 30 hours after operation, the positive rate of cultured bacterial in the blood of portal vein in SDD+Gln group was significantly lower than that in control group (P＜0.05, P＜0.01). The incidence of postoperative pneumonia in SDD+Gln group and SDD group were significantly lower than that in control group (P＜0.05,P＜0.01). Conclusion Gln could nourish intestinal epithelium of mucous membrane.When combined with SDD, it could decreased the incidence of intestinal bacterial translocation occurred during the obstruction of portal vein and after operation, so as to decrease the incidence of postoperative pneumonia.
Objective To explore the effect and mechanism of glutamine to the aberrant crypt foci (ACF) in rat injured by acetic acid. Methods Thirty Wistar rats were averagely divided into three groups: control group, acetic acid group and glutamine group. The colon of the rat was infused with 1% acetic acid. Started to gavage with glutamate two days after modeling glutamine group. The injured colons were studied after fourteen days with light and scanning electronic microscope. Paraffin sections of specimens were prepared and stained with HE. The colon crypts were isolated by HCl digestion method. The expressions of CD44 and ICAM-1 in the epithelial cell of the large intestine mucosa were detected by immunohistochemistry method. Results On the days of 14， the number of ACF in the glutamine group were remarkably decreased as compared with that of the acetic acid group and a branch-like. The expressions of ICAM-1 and CD44 (every 1 000 cells) were 302.1±30.1 and 298.6±28.3 in glutamine group, 223.6±23.5 and 221.5±28.6 in control group, 198.5±19.5 and 215.3±17.8 in acetic acid group, respectively. While the expressions of CD44 and ICAM-1 in intestine were increased remarkably in the glutamine group compared with the control group and acetic acid group (P＜0.05). Conclusion Glutamine could decrease the formation of the ACF injured by acetic acid. Increasing the expressions of CD44 and ICAM-1 may be one of the important factors to decrease the ACF.