Plasma Diamine Oxidase Levels Research Articles

Lactobacillus paracasei from koumiss ameliorates diarrhea in mice via tight junctions modulation

ObjectivesProbiotics are gaining interest as alternative options for antibiotic or antiinflammatory drugs. Probiotics can affect the health of the host through metabolites and competitive inhibition adhesion of pathogenic microorganisms. Koumiss is an important part of the diet of Asian nomads, and is rich in a broad array of probiotics that can benefit the body. Mongolians have developed koumiss therapy to assist in the treatment of various diseases. In the present study, we investigate the beneficial effect of Lactobacillus paracasei, a strain isolated from koumiss, on a mouse model of diarrhea induced by Escherichia coli O8 (E. coli O8). MethodsProbiotics were isolated from Mongolian koumiss. The resistance of probiotics against acid, bile salts, gastric juice, and intestinal juice was evaluated. The mouse model of diarrhea was established by the intragastric administration of E. coli O8 after NaHCO3 treatment. L. paracasei was intragastrically administered before or after E. coli O8 exposure in mice. The plasma levels of diamine oxidase and zounlin were quantified using an enzyme-linked immunosorbent assay, and the integrity of the intestinal barrier and goblet cells of mice with diarrhea were observed using hematoxylin and eosin and Alcian blue periodic acid-Schiff staining. The expression of tight junction (TJ) proteins was detected by immunohistochemistry and Western blot. ResultsA total of five lactic acid bacteria and two yeast strains were isolated from koumiss, and L. paracasei was screened for animal experiments. Experimental results showed that L. paracasei could reduce the increase in diamine oxidase and zonulin caused by E. coli (P < 0.05); increase goblet cells and the expression of TJ proteins ZO-1, occludin, and claudin-1 (P < 0.05); increase the expression of mucin 2, oligomeric mucus/gel-forming (P < 0.05) protein; and reduce the level of inhibitor kappa B-alpha and myosin light-chain kinase. ConclusionsL. paracasei reduced the intestinal permeability, induced the expression of mucin 2, oligomeric mucus/gel-forming protein, and increased the number of goblet cells in mice by the upregulation of the expression of TJ proteins via the nuclear factor kappa B cells–myosin light-chain kinase signaling pathway.

Effect of Clostridium butyricum and Butyrate on Intestinal Barrier Functions: Study of a Rat Model of Severe Acute Pancreatitis With Intra-Abdominal Hypertension.

Background/AimsSevere acute pancreatitis (SAP) is associated with intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS), but treatment of these conditions is difficult. We studied a rat model of SAP + IAH to determine the effect of oral administration of Clostridium butyricum and butyrate (its major metabolite) on intestinal barrier functions.MethodsA total of 48 rats were assigned to four groups, with 12 rats per group: Sham, SAP+IAH, SAP+IAH+C. butyricum, and SAP + IAH + butyrate. SAP was induced by sodium taurocholate infusion into the biliopancreatic duct, intra-abdominal pressure (IAP), mortality was measured 24 h later, and then rats were euthanized. The plasma levels of several markers [amylase, diamine oxidase (DAO), fluorescein isothiocyanate (FITC)-dextran, tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-1β, IL-12, lipopolysaccharide (LPS)] and fecal butyric acid level were determined. The pancreas and intestine were examined using histology, and RT-PCR and Western blotting of intestinal tissues were used to measure the expression of six markers {tight junction proteins [zonula occludens protein-1 (ZO-1), claudin-1, claudin-2, occluding], matrix metalloproteinase 9 [MMP9], and TNF-α}. The gut flora of the rats was examined by 16S rRNA sequencing.ResultsInduction of SAP + IAH altered several functions of the intestinal barrier, and enhanced intestinal permeability, decreased the levels of ZO-1, claudin-1, occludin, the richness and diversity of the microflora community, the relative abundance (RA) of Firmicutes, and the number of probiotic organisms. However, induction of SAP+IAH increased the expression of claudin-2, MMP9, and TNF-α, and the RA of Proteobacteria and pathogens in the feces. Rats that received oral C. butyricum or butyrate had reduced intestinal injury and plasma levels of DAO, LPS, and inflammatory cytokines.ConclusionThis study of rats with SAP+IAH indicated that oral dosing of C. butyricum or butyrate reduced intestinal injury, possibly by altering the functions of the intestinal mucosal barrier.

Role of high mobility group box 1 in intestinal mucosal barrier injury in rat with sepsis induced by endotoxin

To investigate the role and mechanism of the high mobility group box 1 (HMGB1) in intestinal mucosal barrier injury in rat with sepsis induced by endotoxin lipopolysaccharide (LPS). The rats were given intraperitoneal injection of LPS to reproduce a model of sepsis. The effect of HMGB1 inhibitor EP solution (40 mg/kg) on sepsis was observed, and phosphate buffer (PBS) control group was set up. Seventy-two hours after modeling, abdominal aortic blood was obtained, and enzyme-linked immunosorbent assay (ELISA) was used to measure the plasma levels of D-lactic acid and diamine oxidase (DAO) of mucosal barrier permeability. The pathological changes of the intestinal mucosal were observed with light microscope and the Chiu score was recorded. The intestinal mucosal ultrastructural changes were observed with electron microscopy. Real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and Western Blot were used to measure the mRNA and protein expressions of Occludin, inflammatory factor HMGB1 and its downstream signal molecule nuclear transcription factor-κB p65 (NF-κB p65) in the rat small intestine. The results of histopathology and ultrastructure of the small intestine showed that in the LPS group, the intestinal mucosa tissue swelled obviously, part of the glands were incomplete, the infiltration of neutrophils increased, themicrovillus cells were absent, arranged indisorder, and the number of tight connections significantly reduced compared with the PBS control group. The levels of D-lactic acid and DAO indicating mucosal barrier permeability, the levels of inflammatory factor HMGB1 and its downstream signaling molecule NF-κB p65 mRNA and protein expressions in the LPS group were significantly higher than those in the PBS control group, and the mRNA and protein expression of Occludin in the small intestine was significantly lower than that in the PBS control group, suggesting that the intestinal mucosal barrier function in septic rats was damaged, permeability increased, and the structure was damaged. After the administration of the HMGB1 inhibitor EP, the intestinal mucosal barrier damage was significantly improved. The performance was as follows: the Chiu score of the small intestine tissue and the plasma D-lactic acid and DAO levels in the EP intervene group were significantly lower than those in the LPS group [Chiu score: 1.60±0.48 vs. 3.40±0.48, D-lactic acid (mmol/L): 3.30±0.22 vs. 5.30±0.16, DAO (U/L): 23.66±0.97 vs. 30.47±1.11, all P < 0.05]. Occludin mRNA and protein expression levels were significantly higher than those in the LPS group [Occludin mRNA (2-ΔΔCt): 0.82±0.05 vs. 0.37±0.08, Occludin protein (Occludin/β-actin): 1.04±0.09 vs. 0.75±0.11, both P < 0.05], while the mRNA and protein expression levels of HMGB1 and NF-κB p65 were significantly lower than those in the LPS group [HMGB1 mRNA (2-ΔΔCt): 1.63±0.10 vs. 3.57±0.10, HMGB1 protein (HMGB1/β-actin): 1.40±0.07 vs. 1.87±0.07; NF-κB p65 mRNA (2-ΔΔCt): 1.47±0.09 vs. 2.62±0.13, NF-ΚB p65 protein (NF-κB p65/β-actin): 1.24±0.14 vs. 1.60±0.13, all P < 0.05]. Intestinal mucosal barrier function of septic rats was damaged, permeability increased, and structure was damaged. The mechanism may be that the expression of inflammatory factor HMGB1 was up-regulated and promoted the activation of its downstream signaling molecule NF-κB, thereby mediated the inflammatory cascade reaction and caused damage to the intestinal mucosa.

MitoQ Modulates Lipopolysaccharide-Induced Intestinal Barrier Dysfunction via Regulating Nrf2 Signaling.

Background Gut barrier dysfunction with alterant mucosal permeability during sepsis is a challenge problem in clinical practice. Intestinal epithelial cells (IECs) are strongly involved in mucosal oxidative stress and inflammatory response. The current study aimed at investigating the effect of MitoQ, a mitochondrial targeted antioxidant, in the treatment of intestinal injury and its potential mechanism during sepsis. Methods 30 minutes before sepsis induction by lipopolysaccharide (LPS) treatment, mice were treated with MitoQ. Intestinal histopathology, mucosal permeability, inflammatory cytokines, and mucosal barrier proteins were evaluated in the present study. Results MitoQ pretreatment significantly decreased the levels of plasma diamine oxidase, D-lactate, and intestinal histological damage and markedly restored the levels of tight junction proteins (ZO-1 and occludin) following LPS challenge. Furthermore, MitoQ inhibited the LPS-induced intestinal oxidative stress and inflammatory response, evidenced by increased levels of intestinal superoxide dismutase and glutathione, and decreased levels of intestinal IL-1, IL-6, TNF-α, and nitric oxide levels. Mechanically, we found that MitoQ inhibited the oxidative stress via activating nuclear factor E2-related factor 2 (Nrf2) signaling pathway and its downstream antioxidant genes, including HO-1, NQO-1, and GCLM. Conclusions MitoQ exerts antioxidative and anti-inflammatory effects against sepsis-associated gut barrier injury by promoting Nrf2 signaling pathway.

Correlation between intestinal mucosal permeability and prognosis in patients with liver cirrhosis

Objective: To investigate the correlation between changes in intestinal mucosal permeability and prognosis of patients with liver cirrhosis. Methods: Data of 89 cases with liver cirrhosis who were hospitalized in the Hepatology Department of Shanxi Provincial Hospital of Traditional Chinese Medicine from January 2017 to August 2017 were collected as the liver cirrhosis experimental group, and 40 healthy subjects were randomly selected as the healthy control group. JY-DLT, the Intestinal Mucosal Barrier Biochemical Index Analysis System was used to measure the levels of serum diamine oxidase (DAO), D-lactic acid, and endotoxin (ETX) in two groups to evaluate intestinal mucosal barrier function. Spearman's rank correlation test was used to evaluate the correlation between liver cirrhosis prognosis and intestinal mucosal permeability. The results of the two groups were compared by Mann-Whitney H test of two independent samples. One-way Anova was used for intergroup comparison. The pairwise comparison between groups was performed using the LSD or SNK test. Results: The level of ETX in patients with decompensated cirrhosis was significantly higher than that in the compensated phase, and the difference was statistically significant (P < 0.05). The levels of DAO, D-lactic acid and ETX in the liver cirrhosis group were significantly higher than those in the healthy control group, and the differences were statistically significant (P < 0.01). The plasma levels of DAO, D-lactic acid and ETX in the Child-Pugh grade groups of patients with liver cirrhosis were significantly higher than those in the healthy control group, and the differences were statistically significant (P < 0.05). The results of intergroup comparison showed that there were statistically significant differences in DAO, D-lactic acid and ETX levels between Child-Pugh grade A and grade B groups (t = -4.255, 2.527, -2.179, P < 0.05). Furthermore, there were statistically significant differences in the levels of D-lactic acid and ETX between the Child-Pugh grade A and grade C groups (t = -2.693, -4.248, P < 0.01).The plasma levels of DAO, D-lactic acid and ETX levels were positively correlated (r = 0.205, 0.372, 0.342, P < 0.01). D-lactic acid and ETX levels were positively correlated with CTP score, Forns' index, RPR index, APRI score, FIB-4 index and FibroScan score(P < 0.01). Conclusion: The three indices (plasma DAO, D-lactic acid, and ETX) can accurately detect the changes in intestinal mucosal permeability. Moreover, the higher index of intestinal mucosal permeability causes the more severe degree of liver cirrhosis and the correlation between the intestinal mucosal permeability and the prognosis score of liver cirrhosis provides a reference for a new evaluation system and new ideas for the treatment of liver cirrhosis.

Pyrroloquinoline quinone inhibits the production of inflammatory cytokines via the SIRT1/NF-κB signal pathway in weaned piglet jejunum.

The small intestine is an important digestive organ and plays a vital role in the life of a pig. In this study, we explored the regulatory role and molecular mechanism of pyrroloquinoline quinone (PQQ) on intestinal health and to discussed the interaction between PQQ and vitamin C (VC). A total of 160 healthy piglets weaned at 21 d were randomly divided into four treatment groups according to 2 × 2 factoring. The results showed that dietary PQQ could significantly decrease the levels of plasma globulin, albumin/globulin (A/G), indirect bilirubin (IBIL), blood urea nitrogen (BUN), creatinine (CREA) (P < 0.05 for each), total bilirubin, (TBIL) (P < 0.01), diamine oxidase (DAO) (P < 0.01) and immunoglobulin G (IgG) (P < 0.0001) and increase the levels of immunoglobulin A (IgA) and immunoglobulin M (IgM) (P < 0.0001) in the plasma of weaned piglets. Similarly, dietary VC could significantly decrease the levels of plasma globulin, A/G, DAO (P < 0.05 for each) and IgG (P < 0.0001) and increase the levels of IgA and IgM (P < 0.0001) in the plasma of weaned piglets. In addition, dietary PQQ increased (P < 0.05) the mRNA levels of antioxidant genes (NQO1, UGT1A1, and EPHX1), thereby enhancing (oxidized) nicotinamide adenine dinucleotide (NAD+) concentration and sirtuin 1 (SIRT1) activity in tissues. However, the addition of 200 mg kg-1 VC to the diet containing PQQ reduced most of the effects of PQQ. We further show that PQQ reduced (P < 0.05) the expression of inflammation-related genes (IL-2, IL-6, TNF-α, and COX-2) via the SIRT1/NF-κB deacetylation signaling. In conclusion, our data reveals that PQQ exerts a certain protective effect on the intestines of piglets, but higher concentrations of VC react with PQQ, which inhibits the regulatory mechanism of PQQ.

Clinical roles of plasma D-lactate, endotoxin and diamineoxidase in assessment of intestinal mucosal barrier function post traumatic brain injury

Objective To investigate the roles of plasma D-lactate, endotoxin and diamineoxidase (DAO) in assessment of intestinal mucosal barrier function post traumatic brain injury (TBI). Methods We retrospectively studied 70 patients with TBI (TBI group) admitted to Department of Neurosurgery, the 904th Hospital of the Joint Service of Chinese People′s Liberation Army from January 2017 to August 2018, and 45 healthy subjects were enrolled as well (healthy control group) at the physical examination center during the same period. All TBI patients were treated conservatively or surgically. Peripheral blood of patients and healthy subjects were collected to detect levels of plasma D-lactic acid, endotoxin, and DAO. Further use of Spearman correlation analysis was conducted to determine the correlation between preoperative serum D-lactic acid, endotoxin and DAO and Glasgow Coma Scale (GCS) in patients with TBI. Results Compared with the healthy control group, the levels of D-lactic acid (24.7±9.4 mg/L vs. 9.8±4.0 mg/L), endotoxin (9.1±5.8 U/L vs. 4.0±2.2 U/L) and DAO (36.3±22.6 U/L vs. 15.2±3.6 U/L) were significantly increased (t=9.82, 2.84 and 3.49, respectively, all P<0.05). Further correlation analysis showed that serum D-lactic acid, endotoxin and DAO levels were negatively correlated with preoperative GCS scores (r=-0.543, -0.617 and -0.672, respectively, all P<0.01). Conclusion The preliminary results have suggested that the levels of D-lactic acid, bacterial endotoxin and DAO in the serum could be used as important indexes in evaluation of the intestinal mucosal barrier function in patients post TBI. Key words: Traumatic brain injury; Diamineoxidase; D-lactate; Endotoxin; Intestinal mucosa barrier

Plasma diamine oxidase level predicts 6-month readmission for patients with hepatitis B virus-related decompensated cirrhosis

Background and aimsHepatitis B virus-related decompensated cirrhosis is difficult to cure but has a high readmission rate due to multiple complications. Our aim was to investigate the diagnostic potential value of plasma diamine oxidase (DAO) for 6-month readmission of patients with HBV-related decompensated cirrhosis.MethodsA total of 135 patients with HBV-related decompensated cirrhosis were prospectively collected at the onset of discharge of hospital, and then were followed up for at least 6 months with the readmission as the primary outcome. The plasma DAO level was measured using enzyme linked immunosorbent assay. In addition, 120 age and sex matched patients with HBV-related compensated cirrhosis were included as controls.ResultsA total of 36 patients (36.7%) with decompensated cirrhosis admitted to hospital during the 6-month follow up. The plasma DAO level of readmission group [21.1 (14.5; 29.0) ng/ml] was significantly higher than that in the non-readmission group [12.7 (9.3; 18.0) ng/mL, P < 0.001]. Multivariate analysis showed that the plasma DAO level (HR = 1.102, P < 0.05) and hepatic encephalopathy (HE) (HR = 5.018, P < 0.05) were independent factors for 6-month readmission of decompensated cirrhosis. DAO level showed higher area under the curve of receiver operating characteristic (AUROC) than HE (0.769 vs. 0.598, P < 0.05) and Child-Pugh-Turcotte (CPT) score (0.769 vs. 0.652, P < 0.05) for predicting 6-month readmission rate, with the best cut-off value as 19.7 ng/mL. Furthermore, plasma DAO level (HR = 1.184, P < 0.05) was an independent factor and has the higher AUROC than CPT score for the onset of recurrent HE (0.905 vs. 0.738, P < 0.05) during the 6-month follow up.ConclusionsPlasma DAO level > 19.7 ng/mL predicts high rate of 6-month readmission in patients with HBV-related decompensated cirrhosis.

Effects of dexmedetomidine on intestinal barrier function of malignant obstructive jaundice after surgery

Objective To investigate the effects of dexmedetomidine (Dex) on intestinal barrier function (IBF) after surgery of patients with malignant obstructive jaundice (MOJ). Methods Forty patients with MOJ required for operation were selected, and were randomly divided into Dex group (n=20) and control group (n=20). All patients were anesthetized with general anesthesia. Dex group received intravenous infusion of Dex at a dose of 0.5 μg/kg 10 min before induction of anesthesia. In the course of surgery to 0.4 μg·kg-1·h-1 pump injection for 20 min before the completion of surgery. Control group was injected with the same volume of normal saline. Peripheral venous blood was sampled when the patients were in the operating room (T1), at the end of operation (T2), 24 h after operation (T3) and 48 h after operation (T4). The concentration of diamine oxidase (DAO) was measured by enzyme-linked immunosorbent assay (ELISA). Qualitative detection of Escherichia coli DNA was performed by polymerase chain reaction (PCR) technique. Results Two groups of plasma DAO levels in patients had no significant differences (P>0.05) at T1. However, control group was significantly higher than Dex group at T2, T3 and T4, and the difference was statistically significant (P<0.05). The Escherichia coli DNA test was negative at T1. From T2 to T4, the positive cases of Escherichia coli DNA was increased (T2<T3<T4), it was significantly higher in Control group than in Dex group (P<0.05). Conclusions Dex may have protective effect on IBF in patients with MOJ. Key words: Dexmedetomidine; Malignant obstructive jaundice; Intestinal barrier

Paneth cell ablation increases the small intestinal injury during acute necrotizing pancreatitis in rats.

The present work aimed to investigate the role of Paneth cells in small intestinal injury during acute necrotizing pancreatitis (ANP) using rat models established by injection of dithizone, a metal chelator of zinc with the ability to selectively ablate Paneth cells. Sprague-Dawley rats were randomly divided into four groups: Sham-operated group, ANP group (3.5% sodium taurocholate solution, 1 ml/kg body weight), dithizone group (100 mg/kg of body weight) and ANP + dithizone group (sodium taurocholate solution was administered 6 h after dithizone injection). Each group was further divided into five subgroups (6, 12, 24, 36 and 48 h) based on the time period between induction of the model and sample collection. The present results suggested the number of Paneth cells was gradually decreased in the ANP group in a time-dependent manner. Most of the Paneth cells were ablated in the ANP + dithizone group at 6 h, but a subset of Paneth cells recovered after 24–48 h. Compared with the ANP group, combination of dithizone and ANP significantly induced more severe histopathological injuries in the pancreas and distal ileum, with higher Schmidt and Chiu's scores, respectively. Additionally, increased expression levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-17A were detected in the ileum, causing an increase in intestinal permeability, as assessed by a decrease in the expression level of the intestinal tight junction protein occludin and high plasma levels of diamine oxidase and D-lactate. The increase in intestinal permeability led to the translocation of bacteria to the bloodstream, triggering systemic inflammation, as assessed by the increased plasma levels of TNF-α, IL-1β and IL-17A, reducing the survival rates of rats, which was 66.7% and 83.3% in the ANP + dithizone and the ANP group, respectively. The increase in intestinal endoplasmic reticulum stress, as assessed by high expression levels of binding-immunoglobulin protein and activating transcription factor 6, may be one mechanism associated with Paneth cells loss and intestinal barrier impairment during ANP. Collectively, the present study suggested that the absence of Paneth cells may be an important factor involved in intestinal injury, promoting the progression of ANP.

Protective effects of Shenmai injection on intestinal mucosal barrier function in severely scalded rats

To investigate the protective effects of shen-mai injection on intestinal barrier function in the early stage of 30% 3° scald, and to provide experimental basis for the prevention and control of enterogenic infection. A total of 60 Wistar rats were randomly divided into 6 groups: normal control group (without treatment), model control group (with 30% total body surface area (TBSA) fully thickness burn on the back), hexadecadrol (5 mg/kg) group, Shenmai injection (5, 10, 15 mg/kg) groups, with 10 rats in each group. After burned by scald apparatus, rats in each group were treated with drugs immediately by intraperitoneal injection once a day. At 72 hours after burned, the levels of plasma endotoxin, diamine oxidase (DAO), tumor necrosis factor-alpha (TNF-α), interleukins-6(IL-6) in all rats were detected and the mesenteric lymph nodes, liver and spleen were homogenized to culture for bacteria. The change of secretory immunoglobulin A (sIgA) in intestinal mucosa was measured. Compared with normal control group, bacterial translocation quantity in mesenteric lymph nodes(MLN), liver, and spleen, and the plasma levels of DAO, endotoxin, TNF-α, IL-6 and the level of sIgA in intestinal mucosa in model control group were increased significantly (P＜0.01); compared with model control group, bacterial translocation quantity in MLN, liver, and spleen, and the plasma levels of DAO, endotoxin, TNF-α, IL-6 and the level of sIgA in intestinal mucosa in hexadecadrol (5 mg/kg) group and shen-mai injection (5, 10, 15 mg/kg) groups were decreased significantly (P＜0.05 or P＜0.01). Shen-mai injection can alleviate intestinal mucosa injury caused by severe scald, and the effects are similar with those of dexamethasone, and the effect is better in the high-dose group.

Effect of Montmorillonite powder on intestinal mucosal barrier in children with abdominal Henoch-Schonlein purpura: A randomized controlled study.

Background:Our previous studies found that intestinal barrier function has been changed in children with abdominal Henoch–Schonlein purpura (HSP). Montmorillonite has been shown to be protective for digestive tract mucosa.Objective:The present study aimed to investigate whether Montmorillonite powder could improve the intestinal mucosal barrier function in children with abdominal HSP.Methods:Using a randomized controlled study design, we compared plasma levels of diamine oxidase (DAO), d-lactate, and endotoxin in children with abdominal HSP before and after Montmorillonite powder treatment.Results:Among 28 patients in experimental group and 30 in control group, there was no significant difference in age, sex, height, weight, and course of disease between 2 groups (P > .05). Before treatment, there was no statistical difference in DAO, d-lactic acid, and endotoxin between experimental group and the control group (P > .05). However, significant differences were detected for DAO and d-lactate after treatment in comparison to before treatment in the Montmorillonite experimental group (P < .05). Such differences were not found in the control group (P > .05).Conclusion:Montmorillonite powder is effective in the treatment of HSP via maintaining intestinal mucosal barrier function.

Plasma concentration of diamine oxidase (DAO) predicts 1-month mortality of acute-on-chronic hepatitis B liver failure

BackgroundAcute-on-chronic hepatitis B liver failure (ACHBLF) has high 1-month mortality but it is difficult to predict. This present study was aimed to determine the diagnostic value of plasma diamine oxidase (DAO) in predicting the 1-month mortality of ACHBLF. MethodsA total of 106 consecutive newly diagnosed ACHBLF patients were retrospectively collected. The plasma expression of DAO was determined using enzyme-linked immunosorbent assay (ELISA). ResultsThe plasma DAO level of survivals [14.0 (7.1; 26.5) ng/mL] was significantly lower than the nonsurvivals [58.6 (32.5; 121.3) ng/mL, P < .001]. The plasma DAO level, hepatic encephalopathy, spontaneous bacterial peritonitis and model for end-stage liver disease (MELD) score were independent factors associated with the 1-month mortality for ACHBLF. The cut-off point of 15.2 ng/mL for plasma DAO level with sensitivity of 95.45%, specificity of 62.5%, 22.6 for MELD score with sensitivity of 90.91%, specificity of 67.5%, 0.07 for DAO plus MELD with sensitivity of 87.88%, specificity of 80% were selected to discriminate 1-month morality of ACHBLF. Furthermore, DAO plus MELD score showed high AUROC than MELD score for predicting 1-month (0.916 vs. 0.843, P < .01). ConclusionsThe plasma DAO level plus MELD > 0.07 predicts poor 1-month mortality of ACHBLF.

Correlation between acute gastrointestinal injury severity and intestinal microenvironment in rabbits with severe multiple trauma

Objective To investigate the correlation between acute gastrointestinal injury severity and intestinal microenvironment in rabbits with severe multiple trauma. Methods A total of 60 New Zealand white rabbits were enrolled and randomly assigned into the experimental group (48 rabbits) and control group (12 rabbits). In experimental group, the models of traffic-induced injuries were successful made by using self-made small gravity traction colliders. There were nine rabbits with craniocerebral injury combined with damage of liver and spleen, three with four extremity fractures combined with damage of liver and spleen, 12 with rib fractures combined with damage of lungs and pleural effusion, 11 with epidural hematoma, contusion and laceration of brain as well as fractures of four extremities and pelvis, and nine with multiple fractures. The injuries had met the criteria of multiple severe traumas according to the injury severity score (ISS). The control group had similar condition with experimental group except for participation in injury model. The parameters at time points of 6, 12, 24 and 48 h after injury were observed. The parameters were: (1)Enzyme linked immunosorbent assay (ELISA) and high pressure liquid chromatography (HPLC) were used to detect the levels of diamine oxidase (DAO) and the ratio of lactulose to mannitol in urine in order to evaluate the permeability of intestinal mucosal barrier. (2)The small intestinal propulsive rate was detected by carbon pushing method. The interstitial cells of Cajal in the small intestine wall were observed by transmission electron microscopy. The expression of C-kit was detected by Western blot. By these means, the dynamic function of intestinal mucosal barrier was evaluated. (3)The damage degree of intestinal mucosal barrier was evaluated by pathological observation and Chiu score in the end of small intestine and colon. (4)The intestinal bacterial translocation was evaluated by intestinal microflora culture, mesenteric lymph nodes checking as well as translocation examination of liver and spleen. Results (1)The level of DAO plasma and urine lactulose/mannitol ratio at 6 h after injury increased to varied degrees, and reached the peak during 12-24 h, the correlation analysis of which showed that plasma DAO levels were positively correlated with AGI grade at 6, 12 and 24 h (r=0.486 3, 0.493 3, 0.477 6, P<0.05). The ratio of urinary lactulose/mannitol excretion was only positively correlated with AGI grade at 6 and 12 h (r=0.478 5, 0.497 2, P<0.05). (2)The gastrointestinal transmission rate in the experimental group was (48.2±5.2)%, and that of the control group was (60.3±3.0)%. The gastrointestinal transmission rate of model group rabbits was significantly longer than that of control group (P<0.05). (3)The interstitial cells of Cajal decreased dramatically during 12-24 h after the injury, and the expression level of C-kit protein decreased consistently with the increase of AGI grade. (4)The intestinal and colonic mucosa tissues of the experimental group showed obvious necrosis at 12-24 h after injury, and the Chiu score increased gradually with the increase of AGI grade under light microscope. (5)The Enterobacter and Enterococcus in the experimental group increased significantly compared with that in the control group. But the numbers of Bifidobacterium, Lactobacillus, Lactobacillus, Bacteroides as well as the ratio of Bifidobacterium to Enterobacteriaceae significantly decreased(P<0.05). (6)The organ bacterial translocation rates were 24%, 42% and 62% after injury in experimental group (P<0.05). Conclusions Acute gastrointestinal injury may occur early after severe multiple trauma, and the injury severity is closely related to the change of intestinal barrier function and bacterial translocation. Early attention and active correction of the change of intestinal microenvironment are of great importance for treatment of multiple trauma. Key words: Multiple traumas; Intestinal mucosa; Bacterial translocation; Acute gastrointestinal injury

Effect of extracellular histones on intestinal mucosa barrier function in mice and role of extracellular histones in development of sepsis

Objective To investigate the effect of extracellular histones (EH) on intestinal mucosal barrier function in mice and the correlation of EH with the pathogenesis of sepsis. Methods Twenty male C57BL/6 mice were assigned into experiment group (n=10) and control group (n=10) according to the random number table. Same dose (50 mg/kg) of EH and saline were administered through the caudal vein of mice in experiment and control groups respectively. Blood and intestinal samples in each group were collected 3 h after the administration. Morphology of intestinal mucosal tissue was detected by light scope and transmission electron microscope. Expressions of tight junction related proteins (ZO-1, Occludin and Claudin-1) were detected by western blot. Plasma levels of diamine oxidase (DAO) and intestinal fatty acid binding protein (I-FABP) were determined by ELISA method. Plasma level of endotoxin (ET) was determined by limulus test. Results Under transmission electron microscope, experiment group showed disorganized microvilli of intestinal epithelial cells with partially twisted, broken and lost, unclear tight junctions, and widened cellular space. Under light scope, experiment group showed substantial inflammatory cell infiltration in the intestinal wall, disorganized intestinal villi, edema and hemorrhage of mucosa and submucosa, and edematous goblet cells. Experimental versus control group showed significant reduction in levels of Claudin-1 (0.587 7±0.060 6 vs. 0.677 2±0.038 3), Occludin (0.127 7±0.085 7 vs. 0.430 6±0.086 9) and ZO-1 (0.393 3±0.080 8 vs. 0.812 8±0.096 3) (P<0.05). Experimental versus control group showed significantly up-regulated plasma levels of DAO [(1.61±0.20)U/ml vs. (0.69±0.15)U/ml], I-FABP [(548.5±36.8)EU/ml vs. (178.8±26.9) EU/ml] and ET [(0.182±0.076) EU/ml vs. (0.091±0.029) EU/ml](P<0.05). Conclusion EH can obviously impair the integrity of intestinal mucosal barrier in mice and hence induce endotoxin translocation. Key words: Histones; Intestines; Sepsis

Evaluating Intestinal Permeability by Measuring Plasma Endotoxin and Diamine Oxidase in Children with Acute Lymphoblastic Leukemia Treated with High-dose Methotrexate.

The incidence of acute lymphoblastic leukemia (ALL) is highest in childhood malignant tumor in China. The high-dose methotrexate (HDMTX) treatment is very effective in ALL, and it can improve event-free survival rate. However, while executing the anti-tumor effect, it produces highly toxic effects on rapidly dividing cells which are normal. It seems probable that the HDMTX treatment injures intestinal mucosal barrier. The changes of intestinal mucosal barrier can be evaluated through measuring the level of plasma endotoxin and diamine oxidase (DAO). Blood samples were collected from 30 normal children and 30 children with ALL at 1h, 24h, 44h and 68h after HDMTX. The levels of plasma endotoxin and DAO were measured at 1h, 24h, 44h and 68h after HDMTX with spectrophotometry. The levels of endotoxin and DAO were also measured in 4 different courses in 7 children with ALL. The levels of plasma endotoxin and DAO at 1h, 24h, 44h and 68h after HDMTX were higher than in normal children (P<0.01). The levels of plasma endotoxin and DAO at 24h and 44h after HDMTX were both higher than at 1h and 68h (P<0.01). There was no significant difference found in the measured results of plasma endotoxin and DAO at 1h and 68h after HDMTX (P>0.05). There was no significant difference found in the increased levels of endotoxin and DAO at 1h, 24h, 44h and 68h after HDMTX in 4 different courses of 7 children with ALL(P>0.05). By measuring the level of plasma endotoxin and DAO in children with ALL and during HDMTX chemotherapy, the results suggest that there is increased intestinal permeability.

Association of plasma diamine oxidase and intestinal fatty acid–binding protein with severity of disease in patient with heat stroke

ObjectivesThe aim of this study was to describe the role of intestinal fatty acid–binding protein (iFABP) and allergy-related diamine oxidase (DAO) in patients with heat stroke (HS). MethodsA total of 10 patients with HS in intensive care unit and 10 healthy volunteers were enrolled in this study. The plasma intestinal permeability markers iFABP and DAO were measured since the time of admission. The whole blood endotoxin was also assessed. The associations between iFABP, DAO, and endotoxin level were analyzed. Then, white blood cell count, procalcitonin, and C-reactive protein were examined. In addition, we also determined the levels of proinflammatory cytokines such as IL-1α, IL-6, and TNF-α. ResultsComparing with the healthy control, the plasma iFABP and DAO level in patients with HS increased significantly (P < .05). The kinetic curve showed that plasma iFABP and DAO level reached peak value at day 3 and day 4 after admission, respectively. The endotoxin level was positively correlated with iFABP and DAO level. We also observed a significantly increased level of procalcitonin and C-reactive protein but not white blood count in patients with HS. After treatment, the iFABP and DAO level decreased significantly (P < .05). A significant increase in level of IL-1α and IL-6 was also found in patients with HS. ConclusionsThe plasma concentrations of DAO and iFABP could reflect a better function of the intestinal mucosa barrier in patients with HS. Plasma iFABP and DAO level decreased significantly after the treatment and, thus, might be a predictor for the severity of HS.

Surveillance of Intra-Abdominal Pressure and Intestinal Barrier Function in a Rat Model of Acute Necrotizing Pancreatitis and Its Potential Early Therapeutic Window

ObjectivesTo monitor intra-abdominal pressure (IAP) and intestinal barrier function in a rat model of acute necrotizing pancreatitis (ANP) to elucidate a potential relevant therapeutic window.MethodsSprague-Dawley rats were randomly divided into experimental or control groups. The ANP group (n = 40) was injected with 4.5% sodium taurocholate into the pancreatic duct to induce ANP. The controls received only abdominal opening surgery (sham-operated, SO; n = 40) or no treatment or surgery (baseline; 0 h, n = 20). The SO and ANP groups were then randomly subdivided into 3, 6, 12 and 24 h groups (n = 10 each). IAP was measured at each time point and the rats were sacrificed to measure the weight of accumulated ascites fluid and the amylase, endogenous creatinine (Cr), total bilirubin (TB), tumor necrosis factor- alpha (TNF-alpha), diamine oxidase (DAO), and D-lactate. Mortality and the development of pathological changes in the pancreas and intestines were also monitored.ResultsIAP showed a continuous upward trend in the ANP group, with values 2 to 3 times higher than those in the SO group at the corresponding time points and the rising rate was peaking at 6 h. The levels of plasma amylase, TNF-alpha, Cr, TB, DAO, and D-lactate also gradually increased in the ANP group over time and were significantly higher than in the SO group at 3, 6, 12 and 24 h (all P<0.05). Moreover, the rising rate of TNF-alpha, DAO, and D-lactate also peaked at 6 h.ConclusionsThe ANP-induced changes in IAP, inflammatory factors and intestinal barrier that we observed in the rat model were especially obvious at 6 h post-induction, suggesting an early therapeutic window for the treatment of ANP in humans.

A combination of plasma DAO and citrulline levels as a potential marker for acute mesenteric ischemia

IntroductionThere is no valid and reliable diagnostic test for early diagnosis of acute mesenteric ischemia (AMI). The aim of this study was to measure the plasma levels of diamine oxidase (DAO) and citrulline in AMI to gain insight into its early diagnosis.Material and methodsA total of 21 Wistar albino rats were divided into three groups, that is, control group, short-term ischemia group, and prolonged ischemia group. The superior mesenteric artery was occluded for 15 min in the short-term ischemia group and for 12 h in the prolonged ischemia group. Twelve hours later, the experiment was terminated and plasma DAO and citrulline levels were measured. Intestinal tissue was evaluated for the histopathological changes.ResultsCompared to the control group, the short-term and prolonged ischemia groups showed significant increases in the plasma levels of DAO, whereas the plasma citrulline levels decreased significantly. Prolonged ischemia caused a larger increase in the plasma DAO levels and a larger decrease in the plasma citrulline levels compared to the short-term ischemia (p=0.011 and p=0.021, respectively). Intestinal damage was shown to develop more in the prolonged ischemia group (p=0.001).ConclusionIn the early period of AMI, the plasma DAO levels increase while citrulline levels decrease, and the extent of these changes depends on the duration of ischemia.

Effects of simulated weightlessness on tight junction protein occludin and Zonula Occluden-1 expression levels in the intestinal mucosa of rats

This study investigated the tight junction (TJ) protein expression of the intestinal mucosa in a rat tail-suspension model under simulated weightlessness. Twenty-four Wistar rats were randomly divided into three groups: CON group (n=8), control; SUS-14 d group (n=8), tail-suspension for 14 days; SUS-21 d group (n=8), tail-suspension for 21 days. Occludin and Zonula Occluden-1 (ZO-1) expression levels were determined by immunohistochemical analysis and mRNA fluorescent quantitative PCR. Plasma levels of diamine oxidase (DAO) and d-lactate were determined using enzymatic spectrophotometry. Immunohistochemical results for occludin and ZO-1 showed disruption of the TJs in the intestinal mucosa in SUS-14 d and SUS-21 d groups. The expression levels of occludin and ZO-1 in SUS-21 d group were lower than those in SUS-14 d group, and significantly lower than those in CON group (Occldin: 0.86±0.02 vs 1.01±0.03 vs 1.63±0.03 and ZO-1: 0.82±0.01 vs 1.00±0.02 vs 1.55±0.01, P<0.01). Moreover, the levels of plasma DAO and d-lactate in SUS-21 d group were higher than those in SUS-14 d group, and significantly higher than those in CON group (DAO: 27.58±0.49 vs 20.74±0.49 vs 12.94±0.21 and d-lactate: 37.86±0.74 vs 28.26±1.01 vs 17.76±0.91, P<0.01). There were significant negative correlations between occludin or ZO-1 expression levels and DAO (r (2)=0.9014, r (2)=0.9355, P<0.01) or d-lactate levels (r (2)=0.8989, r (2)=0.9331, P<0.01). Occludin and Zo-1 were reduced in intestinal mucosa both in mRNA and protein levels in the rat tail-suspension model. The significant negative correlations between expression levels of TJs and plasma levels of DAO or d-lactate support the hypothesis that intestinal permeability is increased due to a decrease in TJ protein expression during tail-suspension from 14 days to 21 days.