Endotoxin-induced alterations of adipose tissue function:a pathway to bovine metabolic stress

During the periparturient period, dairy cows exhibit negative energy balance due to limited appetite and increased energy requirements for lactogenesis. The delicate equilibrium between energy availability and expenditure puts cows in a state of metabolic stress characterized by excessive lipolysis in white adipose tissues(AT), increased production of reactive oxygen species, and immune cell dysfunction. Metabolic stress, especially in AT, increases the risk for metabolic and inflammatory diseases. Around parturition, cows are also susceptible to endotoxemia. Bacterial-derived toxins cause endotoxemia by promoting inflammatory processes and immune cell infiltration in different organs and systems while impacting metabolic function by altering lipolysis, mitochondrial activity, and insulin sensitivity. In dairy cows, endotoxins enter the bloodstream after overcoming the defense mechanisms of the epithelial barriers, particularly during common periparturient conditions such as mastitis, metritis, and pneumonia, or after abrupt changes in the gut microbiome. In the bovine AT, endotoxins induce a pro-inflammatory response and stimulate lipolysis in AT, leading to the release of free fatty acids into the bloodstream. When excessive and protracted, endotoxin-induced lipolysis can impair adipocyte's insulin signaling pathways and lipid synthesis. Endotoxin exposure can also induce oxidative stress in AT through the production of reactive oxygen species by inflammatory cells and other cellular components. This review provides insights into endotoxins' impact on AT function, highlighting the gaps in our knowledge of the mechanisms underlying AT dysfunction, its connection with periparturient cows' disease risk, and the need to develop effective interventions to prevent and treat endotoxemia-related inflammatory conditions in dairy cattle.

Value of combining the serum D-lactate, diamine oxidase, and endotoxin levels to predict gut-derived infections in cancer patients

Objective:This is a retrospective observational cohort study.The objective of this retrospective observational cohort study was to evaluate the value of the combined serum D-lactic acid,diamine oxidase(DAO),and endotoxin levels to predict intestinal barrier impairment and gut-derived infection(GDI)in cancer patients.Methods:Cancer patients receiving chemotherapy or palliative care treatment at our hospital were enrolled in the study.The serum concentrations of DAO,D-lactic acid,and endotoxin were determined using the intestinal barrier function biochemical index analysis system.The patients'infection information came from the hospital's Medicom Prescription Automatic Screening System and themedical records.Three hundred fifty-three cancer patients were included in the study(53.8%female,73.7%cancer stage IV,27.8%had bowel obstruction).Results:The total incidence of GDI was 33.4%(118/353).The median length of hospital stay was 16 days for patients with GDI,compared with 7 days for patients without GDI(P<0.001).The media hospitalization costs were¥27,362.35 for patients with GDI compared with¥11,614.08 for patients without GDI(P<0.001).The serum concentrations of DAO,D-lactic acid,and endotoxin were significantly higher in patients with GDI.As malignant bowel obstruction(MBO)worsened,the concentrations of DAO,D-lactic acid,and endotoxin increased.Multivariate logistic regression models revealed that the DAO,endotoxin,IL-6,and C-reactive protein levels were significantly associated with an increased risk of GDI.In addition,we also found a fivefold increased risk of infection in patients withMBO compared with those without bowel obstruction(OR=6.210,P<0.001).All of the areas under the receiver operating characteristic curve(AUCs)for DAO,D-lactate,and endotoxin to predict GDI were<0.7(AUC=0.648,P<0.001;AUC=0.624,P<0.01;AUC=0.620,P<0.01,respectively).However,when the parameters were combined(DAO+D-lactate+endotoxin),the predictive power increased significantly(AUC=0.797,P<0.001).Moreover,combining these intestinal barrier indicators and the presence of MBO had better power to predict GDI than either alone(AUC=0.837,P<0.001).Conclusions:Combining the serum DAO,D-lactic acid,and endotoxin levels was a better predictor of GDI than any of the indicators alone,and combining these with the diagnosis of MBO could further improve the efficacy for predicting GDI.

Anti-inflammatory Mechanism of Gamma-linolenic Acid in RAW264.7 Cells

[Objective] The aim was to investigate the anti-inflammatory effect and the mechanism of gamma-linolenic acid on lipopolysaccharide-induced RAW264.7 cells.[Method] Macrophagic system RAW 264.7 cells were cultured in vitro,when cells grew to fusion state,they were pretreated with 0,12.5,25.0,50.0 μmol/L of GLA for 4 h,and then 100 ng/ml of LPS were added to induce for 12 h or 30 min.Meanwhile,the blank control and LPS control were set.And the expression of iNOS,COX-2 and the effect of GLA on IκBα,p-JNK/SAPK（Thr183/Tyr185）,p38 MAPK,p-p38 MAPK（Thr180/Tyr182）,ERK1/2,p-ERK1/2 were detected by Western blot.[Result] GLA significantly inhibited the expression of iNOS and COX-2 in RAW264.7 cells induced by LPS,and in the range of 0-50 μmol/L of GLA,the inhibition effect was concentration-dependent（P0.05）.GLA could significantly inhibited the degradation of IκBα（P0.05）,thereby inhibited the activation of NF-κB.GLA could significantly inhibited the phosphorylation of LPS-induced JNK1/2 and ERK1/2（P0.05）,while it had not significantly effect on the phosphorylation of p38（P0.05）.[Conclusion] GLA had excellent anti-inflammation effect.The inhibition of the phosphorylation of JNK1/2,ERK1/2 and the inhibition of activation of NF-κB might be the important mechanism for the educing of its biological effect.

Effect of early enteral nutrition on postoperative nutritional status and immune function in elderly patients with esophageal cancer or cardiac cancer

To explore the effect of early enteral nutrition （EN） on postoperative nutritional status, intestinal permeability, and immune 6anction in elderly patients with esophageal cancer or cardiac cancer. Methods： A total of 96 patients with esophageal cancer or cardiac cancer who underwent surgical treatment in our hospital from June 2007 to December 2010 were enrolled in this study. They were divided into EN group （n=50） and parenteral nutrition （PN） group （n=46） based on the nutrition support modes. The body weight, time to first flatus/defecation, average hospital stay, complications and mortality after the surgery as well as the liver function indicators were recorded and analyzed. Peripheral blood samples were collected on the days 1, 4 and 7 after surgery. The plasma diamine oxidase （DAO） activity and D-lactate level were determined to assess the intestinal permeability. The plasma endotoxin levels were determined using dynamic turbidimetric assay to assess the protective effect of EN on intestinal mucosal barrier. The postoperative blood levels of inflammatory cytokines and immunoglobulins were determined using enzyme- linked immunosorbent assay （ELISA）. Results： After the surgery, the time to first flatus/defecation, average hospital stay, and complications were significantly less in the EN group than those in the PN group （P〈0.05）, whereas the EN group had significantly higher albumin levels than the PN group （P〈0.05）. On the 7th postoperative day, the DAO activity, D-lactate level and endotoxin contents were significantly lower in the EN group than those in the PN group （all P〈0.05）. In addition, the EN group had significantly higher IgA, IgG, IgM, and CD4 levels than the PN group （P〈0.05） but significantly lower IL-2, IL-6, and TNF-a levels （P〈0.05）. Conclusions： In elderly patients with esophageal cancer or cardiac cancer, early EN after surgery can effectively improve the nutritional status, protect intestinal mucosal barrier （by reducing plasma endoxins）, and enhance the immune function

Pathophysiological consequences of obstructive jaundice and perioperative management

Background: Obstructive jaundice is a common problem in daily clinical practice. Understanding completely the pathophysiological changes in obstructive jaundice remains a challenge for planning current and future management.Data sources: A Pub Med was searched for relevant articles published up to August 2016. The effect of obstructive jaundice on proinflammatory cytokines, coagulation status, hemodynamics and organ functions were evaluated.Results: The effects of obstructive jaundice included biliary tree, the hepatic cell and liver function as well as systemic complications. The lack of bile in the gut, the disruption of the intestinal mucosal barrier,the increased absorption of endotoxin and the subsequent endotoxemia cause proinflammatory cytokine production(TNF-α, IL-6). Bilirubin induces systemic inflammatory response syndrome which may lead to multiple organ dysfunction syndrome. The principal clinical manifestations include hemodynamic instability and acute renal failure, cardiovascular suppression, immune compromise, coagulation disorders,nutritional impairment, and wound healing defect. The proper management includes full replacement of water and electrolyte deficiency, prophylactic antibiotics, lactulose, vitamin K and fresh frozen plasma,albumin and dopamine. The preoperative biliary drainage has not been indicated in overall, but only in a few selected cases.Conclusion: The perioperative management is an essential measure in improving the outcome after the appropriate surgical operation in jaundiced patients especially those with malignancy.

Sodium butyrate attenuates high-fat diet-induced steatohepatitis in mice by improving gut microbiota and gastrointestinal barrier

AIM To investigate whether gut microbiota metabolite sodium butyrate (NaB) is an effective substance for attenuating non-alcoholic fatty liver disease (NAFLD) and the internal mechanisms. METHODS Male C57BL/6J mice were divided into three groups, normal control were fed standard chow and model group were fed a high-fat diet (HFD) for 16 wk, the intervention group were fed HFD for 16 wk and treated with NaB for 8 wk. Gut microbiota from each group were detected at baseline and at 16 wk, liver histology were evaluated and gastrointestinal barrier indicator such as zonula occluden-1 (ZO-1) were detected by immunohistochemistry and realtime-PCR, further serum or liver endotoxin were determined by ELISA and inflammation-or metabolism-associated genes were quantified by real-time PCR. RESULTS NaB corrected the HFD-induced gut microbiota imbalance in mice, while it considerably elevated the abundances of the beneficial bacteria Christensenellaceae, Blautia and Lactobacillus. These bacteria can produce butyric acid in what seems like a virtuous circle. And butyrate restored HFD induced intestinal mucosa damage, increased the expression of ZO-1 in small intestine, further decreased the levels of gut endotoxin in serum and liver compared with HF group. Endotoxin-associated genes such as TLR4 and Myd88, pro-inflammation genes such as MCP-1, TNF-alpha, IL-1, IL-2, IL-6 and IFN-gamma in liver or epididymal fat were obviously downregulated after NaB intervention. Liver inflammation and fat accumulation were ameliorated, the levels of TG and cholesterol in liver were decreased after NaB intervention, NAS score was significantly decreased, metabolic indices such as FBG and HOMA-IR and liver function indicators ALT and AST were improved compared with HF group. CONCLUSION NaB may restore the dysbiosis of gut microbiota to attenuate steatohepatitis, which is suggested to be a potential gut microbiota modulator and therapeutic substance for NAFLD.

Intestinal endotoxemia plays a central role in development of hepatopulmonary syndrome in a cirrhotic rat model induced by multiple pathogenic factors

AIM: To characterize the correlation between severity of hepatopulmonary syndrome (HPS) and degree of hepatic dysfunction,and to explore how intestinal endotoxemia (IETM) affects the development of HPS in cirrhotic rats. METHODS: Male Wister rats were fed with a diet containing maize flour,lard,cholesterol,and alcohol and injected subcutaneously with CCl4 oil solution every two days for 8 wk to induce typical cirrhosis and development of HPS. The animals were also given a nitric oxide (NO) production inhibitor,Nω-nitro-L-arginine methyl ester (L-NAME) intraperitoneally,and an iNOS inhibitor,aminoguanidine hydrochloride (AG) via gavage daily from the end of the 4th wk to the end of the 6th or 8th wk,or a HO-1 inhibitor,zinc protoporphyrin (ZnPP) intraperitoneally 12 h prior to killing. Blood,liver and lung tissues were sampled. RESULTS: Histological deterioration of the lung paralleled to that of the liver in the cirrhotic rats. The number of pulmonary capillaries was progressively increased from 6.1 ± 1.1 (count/filed) at the 4th wk to 14.5 ± 2.4 (count/filed) at the 8th wk in the cirrhotic rats. Increased pulmonary capillaries were associated with increased blood levels of lipopolysaccharide (LPS)(0.31 ± 0.08 EU/mL vs control 0.09 ± 0.03 EU/mL),alanine transferase (ALT,219.1 ± 17.4 U/L vs control 5.9 ± 2.2 U/L) and portal vein pressure. Compared with normal control animals,the number of total cells in bronchoalveolar lavage fluid (BALF) of the cirrhotic rats at the 8th wk was not changed,but the number of macrophages and the ratio of macrophages to total cells were increased by nearly 2-fold,protein expression of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) started to increase significantly at the 4th wk,and reached its peak at the 8th wk in the lung of cirrhotic rats. The increase of iNOS expression appeared to be quicker than that of eNOS. NO2-/NO3-was also increased,which was correlated to the increase of iNOS (r = 0.7699,P < 0.0001) and eNOS (r = 0.5829,P < 0.002). mRNA expression of eNOS and iNOS was highly consistent with their protein expression. CONCLUSION: Progression and severity of HPS as indicated by both increased pulmonary capillaries and histological changes are closely associated with LPS levels and progression of hepatic dysfunction as indicated by increased levels of ALT and portal vein pressure. Intestinal endotoxemia plays a central role in the development of HPS in the cirrhotic rat model by inducing NO and/or CO.

Alcoholic liver disease and the gut-liver axis

Alcoholic liver disease (ALD) is one of the leading causes of liver diseases and liver-related death worldwide. Of the many factors that contribute to the pathogenesis of ALD, gut-derived lipopolysaccharide (LPS) plays a central role in induction of steatosis, inflammation, and fi brosis in the liver. In this review, we discuss the mechanisms by which alcohol contributes to increased gut permeability, the activation of Kupffer cells, and the infl ammatory cascade by LPS. The role of the Toll-like receptor 4 (TLR4) complex in LPS recognition and the importance of the TLR4-induced signaling pathways are evaluated in ALD.

Effect of hepatocyte apoptosis induced by TNF-α on acute severe hepatitis in mouse models

AIM To study the effect of hepatocyteapoptosis and necrosis induced by TNF-α on thepathogenesis of acute severe hepatitis(ASH).METHODS The model of ASH was prepared inD-galactosamine(GAIN)sensitized BALB/c miceby injection of either endotoxin(ET)or tumornecrosis factor-α(TNF-α).Morphologicalchanges of apoptotic hepatocytes were studiedby both light and electron microscope and in siteend labeling method(ISEL).Molecular biologicalchanges of DNA ladder were observed byelectrophoresis of extract from liver tissues.Biochemical changes were measured by alanineaminotransferase(ALT),asparticaminotransferase(AST)and TNF-α.The relationbetween apoptosis and necrosis was evaluatedsimultaneously.RESULTS The sequence of hepatocyteapoptosis,necrosis,and final death from ASHwas observed both in GAIN/ET and GAIN/TNF-agroup.Apoptosis was prominent at 3.5 h and 5 hafter injection of inducer,while necrosis becamedominant at 9 h after challenge.The appearanceof apoptosis was earlier in GAIN/TNF-α groupthan that in GAIN/ ET group.Pretreatment ofmice with antiTNF IgG1 may completely preventthe liver injury induced by GalN/ET.CONCLUSION TNF-α can cause liver damageby inducing hepatic apoptosis and necrosis inmice with endotoxemia.

Multiple pathogenic factor-induced complications of cirrhosis in rats: A new model of hepatopulmonary syndrome with intestinal endotoxemia

AIM： To develop and characterize a practical model of Hepatopulmonary syndrome. （HPS） in rats.METHODS： The experimental animals were randomized into five feeding groups： （1） control （fed standard diet）, （2） control plus intraperitoneal injection with lipopolysaccharide （LPS）, （3） cirrhosis （fed a diet of maize flour, lard, cholesterol, and alcohol plus subcutaneously injection with carbon tetrachloride （CCI4） oil solution）, （4） cirrhosis plus LPS, and （5） cirrhosis plus glycine and LPS. The blood, liver and lung tissues of rats were sampled for analysis and characterization. Technetium 99m-labeled macroaggregated albumin （Tc99m-MAA） was used to test the dilatation of pulmonary microvasculature.RESULTS： Typical cirrhosis and subsequent hepato- pulmonary syndrome was observed in the cirrhosis groups after an 8 wk feeding period. In rats with cirrhosis, there were a decreased PaO2 and PaCO2 in arterial blood, markedly decreased arterial 02 content, a significantly increased alveolar to arterial oxygen gradient, an increased number of bacterial translocated within mesenteric lymph node, a significant higher level of LPS and tumor necrosis factor-α （TNF-α） in plasma, and a significant greater ratio of Tc99m-MAA brain-overlung radioactivity. After LPS administration in rats with cirrhosis, various pathological parameters got worse and pulmonary edema formed. The predisposition of glycine antagonized the effects of LPS and significantly alleviated various pathological alterations.

Probiotics and gut health:A special focus on liver diseases

Probiotic bacteria have well-established beneficial ef-fects in the management of diarrhoeal diseases.Newer evidence suggests that probiotics have the potential to reduce the risk of developing inflammatory bowel diseases and intestinal bacterial overgrowth after gut surgery.In liver health,the main benefits of probiotics might occur through preventing the production and/or uptake of lipopolysaccharides in the gut,and therefore reducing levels of low-grade inflammation.Specific immune stimulation by probiotics through processes involving dendritic cells might also be beneficial to the host immunological status and help prevent pathogen translocation.Hepatic fat metabolism also seems to be influenced by the presence of commensal bacteria,and potentially by probiotics;although the mechanisms by which probiotic might act on the liver are still unclear.However,this might be of major importance in the fu-ture because low-grade inflammation,hepatic fat infil-tration,and hepatitis might become more prevalent as a result of high fat intake and the increased prevalence of obesity.

Gut microbiota in alcoholic liver disease: Pathogenetic role and therapeutic perspectives

Alcoholic liver disease(ALD) is the commonest cause of cirrhosis in many Western countries and it has a high rate of morbidity and mortality. The pathogenesis is characterized by complex interactions between metabolic intermediates of alcohol. Bacterial intestinal flora is itself responsible for production of endogenous ethanol through the fermentation of carbohydrates. The intestinal metabolism of alcohol produces a high concentration of toxic acetaldehyde that modifies gut permeability and microbiota equilibrium. Furthermore it causes direct hepatocyte damage. In patients who consume alcohol over a long period, there is a modification of gut microbiota and, in particular, an increment of Gram negative bacteria. This causes endotoxemia and hyperactivation of the immune system. Endotoxin is a constituent of Gram negative bacteria cell walls. Two types of receptors, cluster of differentiation 14 and Toll-like receptors-4, present on Kupffer cells, recognize endotoxins. Several studies have demonstrated the importance of gut-liver axis and new treatments have been studied in recent years to reduce progression of ALD modifying gut microbiota. It has focused attention on antibiotics, prebiotics, probiotics and synbiotics.

Experimental study on the role of endotoxin in the development of hepatopulmonary syndrome

AIM: To evaluate the role of intestinal endotoxemia in the genesis of hepatopulmonary syndrome. METHODS: A rat model of cirrhosis was prepared with the method of compound factors. At the end of the eighth week, rats with cirrhosis were treated with 300 μg LPS/100 g body weight, and 1 g/rat of glycine about four h prior to LPS. After three h of LPS treatment, blood and tissues were collected for various measurements. Kupffer cells were isolated from male Wistar rats and cultured, and divided into five groups. Supernatant was harvested at 3 h after treatment with LPS for measurement of tumor necrosis factor-alpha (TNF-α). RESULTS: Our results showed that in rats with cirrhosis, slowed and deepened breath with occasional pause was. PaO2, PaCO2 and standard bicarbonate (SB) in arterial blood were decreased. Arterial O2 and actual bicarbonate (AB) were markedly decreased. There was a close correlation between decreased O2 and endotoxin. Metabolic acidosis accompanying respiratory alkalosis was the primary type of acid-base imbalance. The alveolar-arterial oxygen gradient was sharply widened. Massive accumulation of giant macrophages in the alveolar spaces and its wall and widened alveolar wall architecture were observed. The number of bacterial translocations in mesenteric lymph nodes increased. The ratio of TC99M-MAA brain-over-lung radioactivity rose. Endotoxin, and TNF-α, endothelin-1 (ET-1), nitric oxide (NO) in plasma and ET-1, carbon monoxide (CO) in lung homogenates increased. After administration of a given dosage of LPS in rats with cirrhosis, various pathological parameters worsened. Plasma level of endotoxin was related to TNF-α, ET-1, NO in plasma and ET-1, NO, CO in lung homogenates. TNF-α level was related to ET-1 and NO in plasma and lung homogenates and CO in lung homogenate as well. The level of TNF-α increased after infusion of LPS into culture supernatant of Kupffer cells in vitro. However, TNF-α significantly decreased after pretreatment with glycine, PD98059 and SB212850. Glycine could antagonize the effect of LPS in vivo and in vitro. CONCLUSION: Intestinal endotoxemia accompanying by cirrhosis may be an important mechanism in the development of hepatopulmonary syndrome in rats. Overproduction of TNF-α due to endotoxin stimulation of Kupffer cells via mitogen-activated protein kinase (MAPK) signal transduction pathway may be a major mechanism mediating the pathologic alterations of hepatopulmonary syndrome.

Over-starvation aggravates intestinal injury and promotes bacterial and endotoxin translocation under high-altitude hypoxic environment

AIM:To study whether over-starvation aggravates intestinal mucosal injury and promotes bacterial and endotoxin translocation in a high-altitude hypoxic environment.METHODS:Sprague-Dawley rats were exposed to hy-pobaric hypoxia at a simulated altitude of 7000 m for 72 h.Lanthanum nitrate was used as a tracer to detect intestinal injury.Epithelial apoptosis was observed with terminal deoxynucleotidyl transferase dUTP nick end labeling staining.Serum levels of diamino oxidase(DAO),malondialdehyde(MDA),glutamine(Gln),superoxide dismutase(SOD) and endotoxin were measured in intestinal mucosa.Bacterial translocation was detected in blood culture and intestinal homogenates.In addition,rats were given Gln intragastrically to observe its protective effect on intestinal injury.RESULTS:Apoptotic epithelial cells,exfoliated villi and inflammatory cells in intestine were increased with edema in the lamina propria accompanying effusion of red blood cells.Lanthanum particles were found in the intercellular space and intracellular compartment.Bacterial translocation to mesenteric lymph nodes(MLN) and spleen was evident.The serum endotoxin,DAO and MDA levels were significantly higher while the serum SOD,DAO and Gln levels were lower in intestine(P< 0.05).The bacterial translocation number was lower in the high altitude hypoxic group than in the high altitude starvation group(0.47±0.83 vs 2.38±1.45,P<0.05).The bacterial translocation was found in each organ,especially in MLN and spleen but not in peripheral blood.The bacterial and endotoxin translocations were both markedly improved in rats after treatment with Gln.CONCLUSION:High-altitude hypoxia and starvation cause severe intestinal mucosal injury and increase bacterial and endotoxin translocation,which can be treated with Gln.

Effects of endotoxin on endothelin receptor in hepatic and intestinal tissues after endotoxemia in rats

INTRODUCTIONEndothelins(ETs) has a potent and sustainedvasoconstrictive effect on a variety of blood vessels.The vascular smooth muscle cell (VSMC)is thetarget for ETs.VSMC of the whole body containsendothelin receptor (ETR).A great number ofexperiments have shown that three distinctcomplementary DNAs of ETR have been identifiedi.e.,endothelin A receptor(ET_A receptor),endothelin B receptor(ET_B receptor)

Changes of plasma D(-) -lactate, diamine oxidase and endotoxin in patients with liver cirrhosis

BACKGROUND: Plasma D(-)-lactate and diamine oxidase (DAO) can reflect patients' intestinal mucosal condition. We evaluated the changes of plasma D (-)-lactate, DAO and endotoxin activities and their significance in patients with liver cirrhosis. METHODS: Fifty liver cirrhosis patients were enrolled into experimental group and 30 healthy people into control group. The plasma levels of D(-)-lactate, DAO and endo- toxin were detected spectrophotographically. RESULTS: The level of D(-)-lactate was significantly high- er in the experimental group than that in the control group (P<0.01). Significant differences of D (-)-lactate levels were observed in Child-Pugh subgroups of the experimen- tal group (P <0. 01). The level of DAO was significantly higher in the experimental group than that in the control group (P <0.01), but the level of DAO in Child-Pugh sub- group C was significantly lower than that in Child-Pugh subgroup B (P<0.01). The level of endotoxin was signifi- cantly increased in the experimental group except Child Pugh subgroup A (P<0.01). The plasma levels of D(-) lactate, DAO and endotoxin were positively correlated with each other (P<0.01). CONCLUSIONS: The data suggest that both plasma D(-) lactate and DAO activity are sensitive markers for early diagnosis of gut failure and endotoxemia in patients with liver cirrhosis. The impairment of intestinal barrier func- tion may be one of the critical reasons for deterioration of liver cirrhosis.

Study progress on mechanism of severe acute pancreatitis complicated with hepatic injury

Study on the action mechanism of inflammatory mediators generated by the severe acute pancreatitis （SAP） in multiple organ injury is a hotspot in the surgical field. In clinical practice, the main complicated organ dysfunctions are shock, respiratory failure, renal failure, encephalopathy, with the rate of hepatic diseases being closely next to them. The hepatic injury caused by SAP cannot only aggravate the state of pancreatitis, but also develop into hepatic failure and cause patient death, lts complicated pathogenic mechanism is an obstacle in clinical treatment. Among many pathogenic factors, the changes of vasoactive substances, participation of inflammatory mediators as well as OFR （oxygen free radical）, endotoxin, etc. may play important roles in its progression.

Functional changes of intestinal mucosal barrier insurgically critical patients

BACKGROUND： The gut is capable of inducing multiple organ dysfunction syndrome （MODS）. In the diagnosis and treatment of critical ill patients, doctors should pay particular attention to the protection or recovery of intestinal barrier function. However, no reliable diagnostic criteria are available clinically. This study aimed to assess the changes of intestinal mucosal barrier function in surgically critical ill patients as well as their signi？ cance.METHODS： Thirty-eight surgically critical ill patients were enrolled as a study group （APACHE II〉8 scores）, and 15 non-critical ill patients without intestinal dysfunction were selected as a control group （APACHE II〈6）. General information, symptoms, physical signs, and APACHE II scores of the patients were recorded. The patients in the study group were subdivided into an intestinal dysfunction group （n=26） and a non-intestinal dysfunction group （n=12）. Three ml venous blood was collected from the control group on admission and the same volume of plasma was collected from the study group both on admission and in the period of recovery. The plasma concentrations of endotoxin, diamine oxidase （DAO）, D-lactate, and intestinal fatty-acid binding protein （iFABP） were detected respectively. The data collected were analyzed by the SPSS 17.0 software for Windows. RESULTS： The levels of variables were significantly higher in the study group than in the control group （P〈0.01）. They were higher in the intestinal dysfunction group than in the non-intestinal dysfunction group （DAO P〈0.05, endotoxin, D-lactate, iFABP P〈0.01）. In the non-intestinal dysfunction group compared with the control group, the level of endotoxin was not significant （P〉0.05）, but the levels of DAO, D-lactate and iFABP were statistically significant （P〈0.05）. The levels of variables in acute stage were higher than those in recovery stage （P〈0.01）.The death group showed higher levels of variables than the survival group （endotoxin and D-lactate P〈0.01, DAO and iFABP P〈0.05）.CONCLUSION： The plasma concentrations of endotoxin, DAO, D-lactate, and intestinal fatty-acid binding protein （iFABP） could re？ ect a better function of the intestinal mucosa barrier in surgically critical ill patients.

Influence of splanchnic vascular infusion on the content of endotoxins in plasma and the translocation of intestinal bacteria in rats with acute hemorrhage necrosis pancreatitis

The main reason for the death of the patient with acute hemorrhage necrosis pancreatitis (AHNP) is pancreatic infection and multi-organ failure caused by endotoxemia and intestinal bacterial translocation[1-7]. However, the pathogenesis of endotoxemia and intestinal bacterial translocation remains a question[8-10]; moreover, no effective method of prevention and cure for it has been found till now[11 -15] In the present study, we infused low dose dopamine and low molecular weight dextran through the catheters to abdominal aorta and portal vein, and observed its influence on the endotoxin concentration in plasma and the rate of translocation of intestinal bacteria in AHNP rats.

Plasma D(-)-lactate as a new marker for diagnosis of acute intestinal injury following ischemia-reperfusion

IM To observe the kinetics of D()lactate alteration in both portal and systemic circulations, and its relationship with intestinal injury in rats subjected to acute intestinal ischemiareperfusion.METHODS Anesthetized rats underwent 75min superior mesenteric artery occlusion followed by 6hour reperfusion. Plasma D()lactate levels were measured by an enzymatic spectrophotometric assay.RESULTS Intestinal ischemia for 75 min resulted in a significant elevation of D()lactate levels in portal vein as compared with the baseline values (P<005). Plasma D()lactate levels had a tendency to further increase after reperfusion up to 6 hours. Similar alterations in D()lactate were also found in systemic circulation, there were no significant differences between the portal and systemic circulations at any time point. Moreover, the macropathological evaluation scores were significantly correlated to the portal D()lactate levels in animals at various time points (r=0415, P<001). In addition,there was a remarkable rise of endotoxin concentration within the portal vein at the end of 75min ischemia (P<005), reaching a peak at 2 hours postreperfusion.CONCLUSION Acute intestinal ischemia is associated with failure of mucosal barrier resulting in increased plasma D()lactate levels in both portal and systemic blood. The subsequent reperfusion might further increase D()lactate levels, which are correlated to the macropathological alterations. Plasma D()lactate may be a useful marker of intestinal injury following both ischemia and reperfusion insults.