Objective To investigate the effects of expression of TNFα mRNA on glucose uptake in both the liver and skeletal muscle after endotoxemia. Methods In the mice with intraperitoneal injection of lipopolysaccharide (LPS), the changes of TNFα level of plasma and uptake of 2-deoxyglucose (2-DG) in the isolated soleus muscle and hepatic tissues were determined, then the reinstatement of glucose uptake by injecting TNF-McAb for 3 days was also observed. In addition, changes of TNFα mRNA expression of liver were evaluated. Results The expression of TNFα mRNA in the liver showed markedly increased in the first 3 hours post endotoxemia and remaind high for 3 days, and the plasma TNFα level paralleled with TNFα mRNA expression of liver also was elevated. The basal uptake of 2-DG both in muscle and liver were markedly increased, but the stimulated 2-DG uptake with insulin was greatly reduced as compared with the control. In addition, these abnormalities of 2-DG uptake can be partially corrected by neutralization of the circulatory TNFα by administration of TNF-McAb. Conclusion The disorders of glucose uptake of the liver and the muscle due to the overexpression of TNFα mRNA and elevated circulatory TNFα level may be the mechanism of insulin resistance after endotoxemia.
PURPOSE:To investigate and changes of the retina and the chorid induced by lipopolysaccharide (LPS)in Lewis rats and to compare the results obtained on tissue wholemounts and sections. METHODS:Immunohistochemistry was carried out both on wholemounts of the retina and the chorid-sclera complex and on ocular sections from normal Lewis rats and those after LPS injection. RESULTS:It was shown on the tissue wholemounts that monocytes were attached to retinal blood vessels and emigrated into the choroid as early as 4hrs after LPS injection. Severe involvement of the retina and macrophages into whole area of these tissues.Furthermore increasing number of major histocompatibility complex classⅡ(MHC classⅡ)positive cells was observed in the choroid.The results on tissue sections revealed that the retina and the choroid were both involved as videnced by infiltration of these cells at some time points after LPS injection. CONCLUSION:Wholemount technique provides undoubtful evidences to show that the retina and choroid are primarily and severely involuted after LPS injection.The endotoxin induced uveitis is,for the first time,presumed to be model for human generalized uveitis. （Chin J Ocul Fundus Dis,1996,12:33-36）
Objective The effects of endotoxin, cytokines, nitric oxide were reviewed in the development of hyperdynamic circulatory syndrome in portal hypertension. Methods Liceratures of overseas main studies in hyperdynamic circulatory syndrome of portal hypertension in recent 10 years were reviewed. Results The hyperdynamic circulatory syndrome was found in 30%-50% of patients with cirrhosis and in all animal models of portal hypertension. The research results of the effects of endotoxin, cytokines, nitric oxide in the development of hyperdynamic circulatory syndrome were different. Conclusion Hyperdynamic circulatory syndrome contribute to the maintenance and aggregation of portal hypertension. Endotoxin, cytokines, nitric oxide may play a role in the development of hyperdynamic circulatory syndrome. Nitric oxide is a more important factor. The effect of other factors is probably mediated by nitric oxide.
Objective To investigate the relationship of pulmonary surfactant protein D( SP-D) with chronic obstructive pulmonary disease ( COPD) by measuring SP-D level in serum and lung tissue of rats with COPD.Methods The rat COPD model was established by passive smoking as well as intratracheal instillation of lipopolysaccharide ( LPS) . Thirty male SD rats were randomly divided into a control group, a LPS group, and a COPD group( n =10 in each group) . The pathologic changes of lung tissue and airway were observed under light microscope by HE staining. Emphysema changes were evaluated by mean linear intercept ( MLI) of lung and mean alveolar number ( MAN) . The level of SP-D in serum was measured by enzymelinked immunosorbent assay ( ELISA) . The expression of SP-D in lung tissue was detected by Western-blot and immunohistochemistry.Results The MLI obviously increased, and MAN obviously decreased in the COPD group compared with the control group ( Plt;0.05) . There was no significant difference in the MLI and MAN between the LPS group and the control group ( Pgt;0.05) . The serum SP-D level was ( 49.59 ±2.81) ng/mL and ( 53.21±4.17) ng/mL in the LPS group and the COPD group, which was significantly higher than that in the control group [ ( 42.14±2.52) ng/mL] ( Plt;0.05) . The expression of SP-D in lung tissue was 0.56±0.01 and 0.63±0.01 in the LPS group and the COPD group, which was also obviously ber than that in the control group ( 0.39 ±0.01) ( Plt;0.05) .Meanwhile the SP-D levels in serumand lung tissue were higher in the COPD group than those in the LPS group ( Plt;0.05) . The levels of SP-D between serum and lung tissue were positively correlated in all three groups ( r=0.93, 0.94 and 0.93, respectively, Plt;0.01) .Conclusion Both the SP-D level in serum and in lung tissue increase significantly in COPD rats and correlate well each other, which suggests that SP-D may serve as a biomarker of COPD.
Objective To observe the expression of matrix metalloproteinase-9 (MMP-9), its tissue inhibitor of matrix metalloproteinase (TIMP-1), inducible nitric oxide synthase (iNOS) and contents of nitric oxide (NO) in the ocular tissues of Sprague-Dawley (SD) rats with endotoxin induced uveitis（EIU）. Methods Ninety SD rats were randomly divided into experimental (81 rats) and control group (9 rats). The model of EIU was induced in rats in experimental group by injecting with lipoplysaccharide (LPS) 200 μl into the hind feet pads, while the rats in the control group were not injected. Nine rats were executed 0, 6, 12, 18, 24, 48, 72, 96 hours and 7 days, respectively, after injecting with LPS; the NO content and concentration of protein in the aqueous humor in blood plasma, aqueous humor, and uveal tissues were detected. The expressions of MMP-9, TIMP-1 and iNOS in the ocular tissues were detected by immunohistochemistry, and the average absorbance (A) value was evaluated by computer medical image analysis system. Results iNOS, MMP-9 and TIMP-1 expressed in the epithelial cells of iris and ciliary body and exudated inflammatory cells of rats. The concentration of protein in the aqueous humor, the contents of NO in blood plasma, aqueous humor, and uveal tissues, and A value of MMP-9 had obvious relativity with the inflammatory extent, while no positive correlation was found between the inflammatory extent and the A value of iNOS and TIMP-1. Expression of iNOS was found 6 hours after injection, reached the peak after 12 hours, and then dropped gradually. The expression of TIMP-1 could be seen 24 hours after injection, and reached its peak after 72 hours. Conclusion The content of NO and expressions of iNOS, MMP-9 and TIMP-1 changes from the beginning and during the development of EIU, which suggests that NO, iNOS, MMP-9 and TIMP-1 are involved in the pathologic process of EIU. (Chin J Ocul Fundus Dis, 2005, 21: 371-374)
Objective To investigate the expression of aquaporin-1( AQP1 ) in visceral and parietal pleura in SD rats and to examine the effect of AQP1 on pleural fluid turnover. Methods Five groups( n = 24 ) of SD rats were randomly assigned to received intrapleural injection of dexamethasone,lipopolysaccharide, erythromycin, hypertonic saline and normal saline, respectively. The AQP1 protein in pleural was detected with immunohistochemistry. The mRNA expression of AQP1 under stimulations at different time points was measured by real time RT-PCR. Results AQP1 was immunolocalized predominantly to the microvessels and mesothelial cells of visceral and parietal pleura. The extent of AQP1expression in parietal pleura was less than that in visceral pleura[ ( 4. 14 ±1. 12) ×104 copy /μg vs ( 7. 43 ±2. 02) ×104 copy / μg, P lt;0. 05] . AQP1 expression increased at all phases in the dexamethasone group andthe hypertonic saline group, whereas decreased in the erythromycin group and the lipopolysaccharide group.Conclusion The stimulations of dexamethasone, lipopolysaccharide, erythromycin and hypertonic saline can significantly change the AQP1 expression in pleura, which indicate that AQP1 may contribute to the accumulation and clearance of pleuritic fluids.
Objective To investigate the protective effects of endotoxin pretreatment on lung injury of rats with endotoxemia. Methods The rat model of acute endotoxemia was established by injecting lipopolysaccharide (LPS) intraperitoneally. Seventy-two male Wistar rats were randomly divided into three groups, ie. a saline control group (N, n=24) , a LPS-treated group (L, n=24) , and a LPS pretreated group ( P, n=24) . Each group was divided into 2 h, 4 h, 6 h, and 12 h subgroups. The rats in group P were firstly administered with introperitoneal injection of 0.25 mg/kg LPS. After 24 hours, they were subjected to the injection of 0.5 mg/kg LPS. The rats in group N and L received injection of equivalent amount of saline. After 72 hours, the rats in group L and P were challenged with intravenous injection of 10 mg/kg LPS, otherwise saline in group N. Six rats were killed at 2, 4, 6 and 12 hours respectively after injection of LPS in group L and P. The lungs were removed for detecting intercellular adhesion molecule-1 ( ICAM-1) , superoxide dismutase ( SOD) , and malondialdehyde (MDA) . Meanwhile the level of tumor necrosis factoralpha ( TNF-α) in serum was measured, and the pathological changes of lung were also examined. Results The contents of ICAM-1, MDA and TNF-α in the LPS-treated 4 h group were 75.07 ±0. 53, ( 3.93 ± 0.42) μmol/g, and (478.62 ±45.58) pg/mL respectively, significantly higher than those in the saline control group. The endotoxin pretreatment reduced the above indexes to 42.40 ±0.44, ( 2.89 ±0.49) μmol / g and ( 376.76 ±43.67) pg/mL respectively (Plt;0.05) . The content of SOD in the LPS-treated 4 h group was ( 6.26 ±0.31) U/mg, significantly lower than that in the saline control group. The endotoxin pretreatment increased SOD to ( 8.79 ±0.35) U/mg. Conclusion Endotoxin pretreatment can suppress the progress of lung injury in rats with endotoxemia and protect the lung tissue by down-regulating the inflammatory response and oxygen free radical production.
【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.
ObjectiveTo study the changes of lipopolysaccharide binding protein (LBP) in the serum of Wistar rats with obstructive jaundice and to investigate its potential mechanism.MethodsEighty male Wistar rats were randomly divided into obstructive jaundice group (OJ group, n=40） and sham operation group (SO group, n=40）. Before operation and the 5th, 10th, 15th, 20th day after common bile duct ligation, the levels of LBP, endotoxin, tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in plasma were detected in all the rats. ResultsLBP levels in serum increased significantly in OJ group on the 10th day after operation compared with those of SO group. Moreover, LBP levels gradually increased in OJ group with the prolongation of obstructive time. A positive correlation existed between serum LBP and plasma endotoxin, TNF-α and IL-6.ConclusionThe study demonstrates that LBP in serum is high and plays an important role in the pathogenesis of multiple organ injury secondary to obstructive jaundice. It may be an appropriate way to treat patients with obstructive jaundice by decreasing LBP levels in serum.
Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection, and is the leading cause of death in intensive care unit patients due to limited therapies currently. As is known to all, endotoxin is important in the pathogenesis of sepsis, whereby infection triggers a systemic inflammatory response, resulting in release of pro- and anti-inflammatory cytokines, which are thought to be responsible for the tissue damage that occurs in sepsis patients. Therefore, removing endotoxins is considered as an effective way to improve the conditions of sepsis patients. Both Toraymaxin (PMX) and adsorptive membrane such as oXiris can remove endotoxins by adsorption, and in this review we will summarize current studies, included in vitro study, animal study, and clinical research to show the benefit from endotoxin removal by oXiris, and also give some suggestions about oXiris clinical practice from experienced experts.