Objective To observe the expression of GdCl3 on Toll-like receptors (TLRs) of RAW264.7 from murine macrophage cell line induced by lipopolysaccharide (LPS) stimulation. Methods Cells were divided into 3 groups: blank group, LPS group and GdCl3 group. And these cells dyed by goat anti-mouse TLR2/4 poly-antibody and anti-goat IgG labelled with fluorescein isothiocyanate (FITC). The synthesis of TLR2/4 protein were determined by flow cytometry (FCM) analysis and reverse transcription polymerase chain reaction (RT-PCR) analyzed their gene expression. Cell supernatants were taken to measure TNF-α production following the ELISA (enzyme-linked immunosorbent assay) protocol. Results The expressions of TLR2/4 protein and mRNA in GdCl3 group under action of different concentration of GdCl3〔TLR2/4 protein, 200 μmol/L: (70.2±1.28)%/(66.7±2.59)%, 400 μmol/L: (64.9±1.43)%/(60.4±1.25)%, 2 000 μmol/L: (47.4±0.98)%/(32.1±0.74)%; TLR2/4 mRNA (the value of absorbance), 200 μmol/L: (76.42±2.76)/(101.72±3.14), 400 μmol/L: (75.60±3.76)/(89.65±5.17), 2 000 μmol/L: (64.22±4.67)/(78.44±4.88)〕 were significantly lower than those of in LPS group 〔TLR2/4 protein: (94.4±1.76)%/(95.7±0.87)%, P<0.01; TLR2/4 mRNA: (127.64±3.25)/(119.82±5.59), P<0.05, P<0.01〕. The expression of TNF-α in GdCl3 group under action of different concentration of GdCl3〔200 μmol/L: (2 540±77) pg/ml, 400 μmol/L: (2 041±106) pg/ml, 2 000 μmol/L: (1 020±220) pg/ml〕 was also significantly lower that that of in LPS group 〔(4 688±127) pg/ml, P<0.01)〕. Conclusion GdCl3 significantly inhibits TLR expression and secretion of TNF-α under the condition of LPS stimulation in vivo.
【Abstract】ObjectiveTo investigate the influence of CO2 pneumoperitoneum on intestinal mucosa permeability in rats with liver cirrhosis. MethodsFifty rats were randomly divided into following groups: control group (n=5), cirrhosis group(n=5) and pneumoperitoneum group (n=40); the pneumoperitoneum group was further divided into 8 mm Hg group(n=20) and 13 mm Hg group (n=20). Four time points were chosen, including 0.5, 2, 6, and 12 hours after the end of pneumoperitoneum. After rat models with cirrhosis were established successfully, the abdominal cavity was insufflated with CO2 and maintained under the pressures of 8 mm Hg and 13 mm Hg respectively for two hours. The portal venous blood was collected and the levels of Dlactic acid and endotoxin were measured. ResultsThe levels of endotoxin and Dlactic acid in cirrhosis group were much higher than those of control group(P<0.05). The levels of serum endotoxin and Dlactic acid in pneumoperitoneum group were higher than those of cirrhosis group(Plt;0.05) regardless of pressure and time point. The endotoxin level in 13 mm Hg group was higher than that of 8 mm Hg group on different time points (F=5.466, P<0.05), but there was no difference in Dlactic acid level between both of them(F=0.415,Pgt;0.05).ConclusionThe intestinal mucosa permeability is increased in rats with liver cirrhosis. It can be further increased under CO2 pneumoperitoneum with certain pressure and time and in a pressuredependent manner. The permeability can decrease after removal of pneumoperitoneum.
ObjectiveTo investigate the changes of diamine oxidase(DAO) and endotoxin(ET) during the treatment of systemic inflammatory response syndrome with human growth hormone and the relationship between human growth hormone and intestinal mucosal barrier injury. MethodsOne hundred and fortysix patients with systemic inflammatory response syndrome were randomly divided into operative group and nonoperative group, which were again randomly divided into the study group and control group.Plasma concentration of DAO and ET were determined before the treatment and 1 week after the treatment.ResultsPlasma concentration of DAO and ET in study group decreased after treatment with significant difference (P<0.05,P<0.01).ConclusionHuman growth hormone can protect intestinal mucosa barrier.
Objective To study endotoxin release induced by differential antibiotics in gram negative bacterial infection. Methods Thirty critical patients accompanied with gram negative bacterial infection were divided into group A (imipenem group, n=15) and group B (ceftazidine group, n=15). Imipenem (0.5 g iv q8h) and ceftazidine (1.0 g iv q8h) were given respectively. White blood cell (WBC), systolic blood pressure (SBP), lipopoly sacchride (LPS), tumor necrosis factor alpha (TNFα) and high density lipoprotein (HDL) were determined in 0, 1, 2, 3, 5 and 7 day. Results There was no difference in the change of WBC between two groups. Group A had a more stable SBP than group B. There was lower endotoxin release in group A than in group B and so were the cytokines release. HDL level was lower in group B than in group A. Conclusion Imipenem has lower endotoxinliberating potential than ceftazidine and mediate lower cytokines release. HDL may protect the patients from LPS damage.
Objective To investigate the effect of recombinant human growth hormone (rhGH) on intestinal bacteria and endotoxin translocation in experimental obstructive jaundice. MethodsObstructive jaundice rat models were made and divided into three groups: sham operation (SO) group, obstructive jaundice (OJ) group and obstructive with rhGH (OG) group. The number in each group was 20. The mice in rhGH group underwent subcutaneous injection each day of Saizen, with the dose of 0.75 u/kg, while SO group and OJ group received nitric sodium injection. All these maitained for 2 weeks, then the animals were killed and the endotoxin were determined by limulus test, and bacterial cultures of ascites, blood, mesenchymal lymph node, kidney, spleen and liver were made, and the height of villi and the thickness of intestinal walls were examined.ResultsThe value of endotoxin in OJ group was (0.77±0.03) u/ml, higher than that in OG group and SO group, while it was (0.40±0.02) u/ml and (0.33±0.03) u/ml (Plt;0.01). The bacteria translocation rate in OJ group was 58.8%, much higher than that in OG group, which was 10.0% (Plt;0.01). There was no difference between OG group and SO group (Pgt;0.05). Villi height in OJ group was (183.39±11.09) μm, and thickness was (255.62±16.58) μm. While in OG group was (237.52±13.65) μm, and (320.81±14.34) μm (Plt;0.01) respectively.Conclusion rhGH has significant effect on protecting the injuried mucosa barrier in obstructive jaundice, and can decrease endotoxemia and bacteria translocation.
ObjectiveTo explore the effect of endotoxin on insulin secretion from islet βcell of rat pancreas.MethodsAfter the model of endotoxemia was established in rats with intraperitoneal injection of LPS (2 mg/kg),the changes of insulin level in the serum and pancreas were dynamically determined, the expression of inducible nitric oxide synthase (iNOS) by situ hybridization and DNA damage in islet cells were also observed, the effect of sodium nitroprusside (exogenous NO) on synthesis and secretion of insulin from isolated islet βcell of normal rat pancreas under high glucose stimulation was also evaluated.ResultsThe level of glucose and insulin in plasma were significantly increased at 12th and 6th h, respectively and kept on 3 d after injection of LPS,but the insulin level in pancreas was not remarkably altered.The expression of iNOS and DNA damaged significantly enhanced at 6 d after endotoxemia. The high glucosestimulated insulin synthesis and secretion were bly inhibited by exogenous NO.ConclusionThese findings suggest that LPS be stimulate the expression of iNOS and NO product,which inhibites synthesis and secretion of insulin in islet βcells,but it stimulates insulin secretion by another mechanism,and results in dysfunction and destruction of the rat pancreas.
【Abstract】Objective To investigate the preventive role of selective decontamination of the digestive tract (SDD) in gut-originated endotoxemia in acute necrotizing pancreatitis (ANP). Methods A lethal model of ANP was reproduced in Wistar rats by retrograde infusion of artificial bile into the main pancreatic duct. Normal control group (n=6), sham operation group (n=6), ANP group (n=14) and ANP+SDD (polymycin E, tobramycin and nystatin mixture) group (n=8) were randomly devided. Visceral pathologic changes, serum levels of TNFα and IL-1β, intestinal bacterial flora, plasma D(-)lactate and endotoxin contents, as well as the mortality were examined at 72h after operation in each group. Results Necrosis and inflammation of pancreas, with a remarkable elevation of serum TNFα and IL-1β and intestinal flora disturbance (with E.Coli content risen significantly) were seen in ANP rats. Simultaneously, ANP rats displayed elevated plasma concentration of D(-)lactate and endotoxin. In SDD group, enterobacteraceae and yeast were markedly depressed, while anaerobes were well preserved, with the value of B/E 〔Bifidobacterium/E.Coli, log10(CFU/CFU)〕 elevated in the ileac mucous membrane (1.73±1.23 vs -0.37±0.72 in ANP group,P<0.01) and in the caecum content (∞ vs 0.88±0.77). In addition, depressed levels of D(-)lactate 〔(3.95±1.83) mg/L vs (8.05±3.05) mg/L in ANP group,P<0.01〕, endotoxin 〔(0.227±0.084) EU/ml vs (0.423±0.155) EU/ml in ANP group, P<0.01〕 and TNFα 〔(15.41±10.32) ng/L vs (46.79±24.31) ng/L in ANP group P<0.01〕 in systemic or portal vein were observed in the SDD group. Moreover, SDD group displayed a declined 72h mortality(14.3% vs 58.8% in ANP group, P=0.005). Conclusion ANP is associated with gut barrier disorder and gut flora imbalance, which may exacerbate the process of gut-originated endotoxin translocation. By protecting gut flora and gut barrier against disorder, SDD attenuates ANPrelated endotoxemia and improves the outcome. SDD is advisable for the prophylaxis of gut-originated endotoxemia complicated from ANP.
To observe the change in plasma endotoxin and cytokine during the early period of intra-abdominal infection (IAI) complicated by multiple system organ dysfunction (MSOD) in animals. Twenty rabbits were randomly divided in to two groups. One group received the operation of cecal ligation plus puncture (CLP) inducing IAI complicated by MSOD, and another group received sham operation as a control. All animals were placed in metabolic cages and maintained with intravenous infusion for one week. Plasma levels of endotoxin and cytokine (TNF, IL-1, IL-6) were determined seperately at the beginning (0 hour) or 1, 2, 3, 4, 5, 6 and 24 hours after CLP. Blood bacteria cultures and pathological examination of several organs were made when the animal was dead or killed. Results: The levels of plasma endotoxin, TNF and IL-6 were found to be significantly increased at one or two hours after CLP, the incidence rate of bacteriemia was 80% and the pathological alterations in the abdomen and organs were remarkale, with an average survival time of 84.1±39.0 hours in CLP group. No change in plasma IL-1 level was found in the CLP group. Conclusion: The plasma levels of endotoxin and cytokine (TNF and IL-6) do increase in the early period of IAI complicated by MSOD, and the change in plasma IL-1 is not obvious.
To study the role of endotoxin in acute hemorrhagic necrotizing pancreatitis (AHNP), the change of endotoxin were studied in rats AHNP models by injection of 5% sodium taurocholate 1 ml/kg into pancreatic duct, and the effects of recombinant interleukin-2 (IL-2) in the treatment of AHNP were observed in this experiment. The results indicated that endotoxin involved the aggravation of AHNP and was associated with the increase of serum phospholipas-2 (PLA2), and these mediators were positively correlated with severe degrees of pancreatic damage. The results also suggeste that IL-2 might inhibit the overexpression of endotoxin and PLA2 and mitigate the pancreatic injury and decrease the 72h-mortality rate of AHNP from 66.7% to 26.7% (P<0.01). Endotoxin might play a major role in the pathogenesis of AHNP and IL-2 might have a potential role in the treatment of AHNP.
The purpose of this study was to determine the contribution of endotoxin (ET) in ocurrence and progression of acute pancreatitis (AP). The results indicated that correlation of ET changes with multiple organ damage in AP. The degree of ET elevation correlated well with the severty of AP. The level of plasma ET of severe AP patients was much higher than that of mild AP patients (P<0.05). The chance of multiple organ damage got greater while the plasma ET level got higher. Moreover, the severety change of severe AP correlated with the change of plasma ET level. In other words, the ET level was reduced while the disease was recovering, elevated while it was becoming worse and maintained high level in dead cases. We think that plasma ET level can be used as a reference for differenciating mild AP with severe AP and a predictor for the prognosis of AP.