• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.405-414
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• 1999

The role of platelet-activating factor (PAF) was investigated in intestinal ischemia/reperfusion (I/R) induced acute lung injury associated with oxidative stress. To induce acute lung injury following intestinal I/R, superior mesenteric arteries were clamped with bulldog clamp for 60 min prior to the 120 min reperfusion in Sprague-Dawley rats. Acute lung injury by intestinal I/R was confirmed by the measurement of lung leak index and protein content in bronchoalveolar lavage (BAL) fluid. Lung leak and protein content in BAL fluid were increased after intestinal I/R, but decreased by WEB 2086, the PAF receptor antagonist. Furthermore, the pulmonary accumulation of neutrophils was evaluated by the measurement of lung myeloperoxidase (MPO) activity and the number of neutrophils in the BAL fluid. Lung MPO activity and the number of neutrophils were increased (p＜0.001) by intestinal I/R and decreased by WEB 2086 significantly. To confirm the oxidative stress induced by neutrophilic respiratory burst, gamma glutamyl transferase (GGT) activity was measured. Lung GGT activity was significantly elevated after intestinal I/R (p<0.001) but decreased to the control level by WEB 2086. On the basis of these experimental results, phospholipase $A_2\;(PLA_2),$ lysoPAF acetyltransferase activity and PAF contents were measured to verify whether PAF is the causative humoral factor to cause neutrophilic chemotaxis and oxidative stress in the lung following intestinal I/R. Intestinal I/R greatly elevated $PLA_2$ activity in the lung as well as intestine (p<0.001), whereas WEB 2086 decreased $PLA_2$ activity significantly (p<0.001) in both organs. LysoPAF acetyltransferase activity, the PAF remodelling enzyme, in the lung and intestine was increased significantly (p<0.05) also by intestinal I/R. Accordingly, the productions of PAF in the lung and intestine were increased (p<0.001) after intestinal I/R compared with sham rats. The level of PAF in plasma was also increased (p<0.05) following intestinal I/R. In cytochemical electron microscopy, the generation of hydrogen peroxide was increased after intestinal I/R in the lung and intestine, but decreased by treatment of WEB 2086 in the lung as well as intestine. Collectively, these experimental results indicate that PAF is the humoral mediator to cause acute inflammatory lung injury induced by intestinal I/R.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.3
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• pp.263-273
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• 1999

The role of phospholipase $A_2\;(PLA_2)$ in acute lung leak induced by intestinal ischemia was investigated in association with neutrophilic respiratory burst. To induce lung leak, we generated intestinal ischemia for 60 min prior to the 120 min reperfusion by clamping superior mesenteric artery in Sprague-Dawley rats. Acute lung leak was confirmed by the increased lung leak index and protein content in bronchoalveolar fluid. These changes were inhibited by mepacrine, the non-specific $PLA_2$ inhibitor. The lung myeloperoxidase (MPO) activity denoting the pulmonary recruitment of neutrophils was increased by intestinal I/R, but decreased by mepacrine. Simultaneously, the number of leukocytes in bronchoalveolar fluid was increased by intestinal ischemia/reperfusion (I/R) and decreased by mepacrine. Gamma glutamyl transferase activity, an index of oxidative stress in the lung, was increased after intestinal I/R but decreased by mepacrine, which implicates that $PLA_2$ increases oxidative stress caused by intestinal I/R. The $PLA_2$ activity was increased after intestinal I/R not only in the intestine but also in the lung. These changes were diminished by mepacrine. In the cytochemical electron microscopy to detect hydrogen peroxide, intestinal I/R increased the generation of the hydrogen peroxide in the lung as well as in the intestine. Expression of interleukin-1 (IL-1) in the lung was investigated through RT-PCR. The expression of IL-1 after intestinal I/R was enhanced, and again, the inhibition of $PLA_2$ suppressed the expression of IL-1 in the lung. Taken together, intestinal I/R seems to induce acute lung leak through the activation of $PLA_2$, the increase of IL-1 expression associated with increased oxidative stress by neutrophilic respiratory burst.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.2
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• pp.147-152
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• 2016

Present study aimed to investigate the effect of curcumin-pretreatment on intestinal I/R injury and on intestinal mucosa barrier. Thirty Wistar rats were randomly divided into: sham, I/R, and curcumin groups (n=10). Animals in curcumin group were pretreated with curcumin by gastric gavage (200 mg/kg) for 2 days before I/R. Small intestine tissues were prepared for Haematoxylin & Eosin (H&E) staining. Serum diamine oxidase (DAO) and tumor necrosis factor (TNF)-${\alpha}$ levels were measured. Expression of intestinal TNF-${\alpha}$ and tight junction protein (ZO-1) proteins was detected by Western blot and/or immunohistochemistry. Serum DAO level and serum and intestinal TNF-${\alpha}$ leves were significantly increased after I/R, and the values were markedly reduced by curcumin pretreatment although still higher than that of sham group (p<0.05 or p<0.001). H&E staining showed the significant injury to intestinal mucosa following I/R, and curcumin pretreatment significantly improved the histological structure of intestinal mucosa. I/R insult also induced significantly down-regulated expression of ZO-1, and the effect was dramatically attenuated by curcumin-pretreatment. Curcumin may protect the intestine from I/R injury through restoration of the epithelial structure, promotion of the recovery of intestinal permeability, as well as enhancement of ZO-1 protein expression, and this effect may be partly attributed to the TNF-${\alpha}$ related pathway.

• Molecules and Cells
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• v.41 no.4
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• pp.290-300
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• 2018

Using an in vitro model of intestinal organoids derived from intestinal crypts, we examined effects of indole-3-carbinol (I3C), a phytochemical that has anticancer and aryl hydrocarbon receptor (AhR)-activating abilities and thus is sold as a dietary supplement, on the development of intestinal organoids and investigated the underlying mechanisms. I3C inhibited the in vitro development of mouse intestinal organoids. Addition of ${\alpha}$-naphthoflavone, an AhR antagonist or AhR siRNA transfection, suppressed I3C function, suggesting that I3C-mediated interference with organoid development is AhR-dependent. I3C increased the expression of Muc2 and lysozyme, lineage-specific genes for goblet cells and Paneth cells, respectively, but inhibits the expression of IAP, a marker gene for enterocytes. In the intestines of mice treated with I3C, the number of goblet cells was reduced, but the number of Paneth cells and the depth and length of crypts and villi were not changed. I3C increased the level of active nonphosphorylated ${\beta}$-catenin, but suppressed the Notch signal. As a result, expression of Hes1, a Notch target gene and a transcriptional repressor that plays a key role in enterocyte differentiation, was reduced, whereas expression of Math1, involved in the differentiation of secretory lineages, was increased. These results provide direct evidence for the role of AhR in the regulation of the development of intestinal stem cells and indicate that such regulation is likely mediated by regulation of Wnt and Notch signals.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.3
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• pp.181-187
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• 2009

Intestinal ischemia/reperfusion (I/R) is one of common causes of acute lung injury (ALI). Early and accurate diagnosis of patients who are like to develop serious acute respiratory distress syndrome (ARDS) would give a therapeutic advantage. Ferritin and heme oxygenase-1 (HO-1) are increased by oxidative stress and are potential candidates as a predictive biomarker of ARDS. However, the mechanisms responsible for the increases of ferritin and HO-1, and their relationship to ALI, are unclear. In order to elucidate the interactions between ferritin and HO-1, we studied the changes in ferritin and HO-1 levels in serum and bronchoalveolar lavage (BAL) fluid after intestinal I/R injury in rats. Leukocyte number and protein contents in BAL fluid were elevated following I/R, and the increases were attenuated by mepacrine pretreatment. Both serum ferritin and HO-1 concentrations were progressively elevated throughout the 3 h observation period. Mepacrine pretreatment attenuated the increase of serum and BAL fluid ferritin concentrations, but did not suppress the increase of serum HO-1. Moreover, BAL fluid HO-1 levels did not change after I/R or after mepacrine pretreated I/R compared with sham rats. Unlike ferritin, HO-1 levels are not exactly matched with the ALI. Therefore, there might be a different mechanism between the changes of ferritin and HO-1 in intestinal I/R-induced ALI model.

• Journal of Life Science
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• v.19 no.6
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• pp.818-824
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• 2009

The mechanisms responsible for ischemia/reperfusion (I/R) injury have direct or indirect relevance to clinical lung injury after severe shock, cardiopulmonary bypass, and transplantation. This study investigated the effects of aspirin on intestinal I/R-induced acute lung injury (ALI) in rats. Lipopolysaccharide (LPS) induced cyclooxygenase-2 (COX-2) expression in A549 and RAW264.7 cells. RAW264.7 macrophages had shown greater expression of COX-2 than A549 cells. In addition, the NADPH oxidase inhibitor apocynin and p38 MAPK inhibitor SB203580 attenuated LPS-stimulated COX-2 expression. To induce ALI, intestinal ischemia was performed for 60 min prior to the 4 hr reperfusion by clamping the superior mesenteric artery in Sprague-Dawley rats. In order to test and compare the effect of non-specific COX inhibitor aspirin with the effect of mepacrine, a well known phospholipase$A_{2}$ inhibitor, rats were divided into 4 groups: Sham, I/R, Mepa+I/R (mepacrine, 60 mg/kg, i.p.), ASA+I/R (aspirin, 10 mg/kg, i.p.). In the present investigation, myeloperoxidase activities in the lung and intestinal tissues were increased by I/R. These changes were reduced by single pretreatment of mepacrine (60 mg/kg, i.p.) or aspirin (10 mg/kg, i.p.) 30 min before I/R. Structural studies demonstrated that the tissue injuries in the lung and intestine after I/R were also attenuated by the pretreatment of mepacrine or aspirin. These results suggest that I/R-induced ALI is mediated, in part, by the activation of COX. In addition, pretreatment of aspirin might be helpful for the prevention of ALI in ARDS-prone patients. In addition, the p38 MAPK inhibitor and apocynin also might be helpful to ALI through the inhibition of COX-2 expression.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.4
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• pp.187-191
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• 2006

Serum ferritin levels are increased in subjects at-risk for or with acute lung injury (ALI), and there are observations to suggest that increases in serum ferritin levels may help predict the development of ALI in at-risk individuals. To deepen our understanding of increases of serum ferritin and their relationship to the development of ALI, we measured serum ferritin levels before and after intestinal ischemia/reperfusion (I/R) injury in rats, and found that serum ferritin levels increased significantly following I/R. Increases in serum and lavage ferritin levels paralleled increases in lung inflammation (lavage leukocyte numbers and tissue myeloperoxidase activities) and lung leak (lavage protein levels). In contrast, pre-treatment of rats with mepacrine (60 mg/kg, i.p.), a phospholipase $A_2$ inhibitor, attenuated not only I/R-induced serum and lavage ferritin increases, but also the development of ALI. These findings indicate that, besides of human subjects with ALI, serum ferritin levels increase early on also in an animal model of ALI. Therefore, serum and lavage ferritin can be a candidate for early biomarker of ALI.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1822-1829
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• 2003

Porcine colostrum and milk were separated into the acid-soluble and casein fractions by acidification followed by centrifuge. The acid-soluble fraction of porcine colostrum was further separated by liquid chromatography and anisotropic membrane filtration. Trypsin and chymotrypsin inhibitory capacity in porcine colostrum, milk and their components was determined by incubating bovine trypsin or chymotrypsin in a medium containing their corresponding substrates with or without addition of various amounts of porcine colostrum, porcine milk or their components. The inhibition of insulin-like growth factor I (IGF-I) and epidermal growth factor (EGF) degradation in pig small intestinal contents by porcine colostrum was measured by incubating iodinated IGF-I or EGF with the intestinal contents with or without addition of porcine colostrum. Degradation of labeled IGF-I or EGF was determined by monitoring the generation of radioactivity soluble in 30% trichloroacetic acid (TCA). The results showed that porcine colostrum had high levels of trypsin and chymotrypsin inhibitory activity and increased the stability of IGF-I and EGF in pig intestinal contents. The inhibitory activity declined rapidly during lactation. It was also found that trypsin and chymotrypsin inhibitory activity and the inhibition on IGF-I and EGF degradation in the acid-soluble fraction were higher than that in the casein fraction. Heat-resistance study indicated that trypsin inhibitors in porcine colostrum survived heat treatments of $100^{\circ}C$ water bath for up to 10 min, but exposure to boiling water bath for 30 min significantly decreased the inhibitory activity. Compared with the trypsin inhibitors, the chymotrypsin inhibitors were more heatsensitive. Separation of the acid-soluble fraction of porcine colostrum by liquid chromatography and anisotropic membrane filtration revealed that the trypsin and chymotrypsin inhibitory capacity was mainly due to a group of small proteins with molecular weight of 10,000-50,000. In conclusion, the present study confirmed the existence of high levels of protease inhibitors in porcine colostrum, and the inhibition of porcine colostrum on degradation of milk-borne growth factors in the pig small intestinal tract was demonstrated for the first time.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.12
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• pp.1749-1754
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• 2014

The current experiment was designed to evaluate the efficacy of adding the multi-enzyme mixture (Natuzyme) into layers' diets with different levels of energy and available phosphorus in relation to laying performance, egg qualities, blood cholesterol level, microflora and intestinal viscosity. Two hundred and fifty 43-wk-old Hy-Line commercial layers were divided into five groups with five replicates per group (10 birds per replicate) and fed one of five experimental diets. A corn and soybean meal-based control diet was formulated and used as a control diet. Two experimental control diets were formulated to reduce energy and crude protein contents (rE) or energy, crude protein and phosphorus contents (rEP). In addition, Natuzyme was added into either rE (rE-Natu500) or rEP (rEP-Natu500) diet to reach a concentration of 500 mg per kg of diet. The experiment lasted 8 weeks. There were no significant differences in feed intake, egg production, egg weight, egg qualities such as eggshell color or Haugh unit, total cholesterol, relative organ weights and cecal microflora profiles between any dietary treatments. Natu500 supplementation into the rE diet, but not rEP diet significantly increased egg mass and eggshell qualities such as strength and thickness, but it decreased cecal ammonia concentration and intestinal viscosity in laying hens. In conclusion, the present study shows that adding multiple enzyme preparation could improve performance of laying hens fed energy and protein restricted diets.

• Parasites, Hosts and Diseases
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• v.49 no.3
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• pp.245-254
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• 2011

Many immune down-regulatory molecules have been isolated from parasites, including cystatin (cystain protease inhibitor). In a previous study, we isolated and characterized Type I cystatin (CsStefin-1) of the liver fluke, Clonorchis sinensis. To investigate whether the CsStefin-1 might be a new host immune modulator, we induced intestinal inflammation in mice by dextran sodium sulfate (DSS) and treated them with recombinant CsStefin-1 (rCsStefin-1). The disease activity index (DAI) increased in DSS only-treated mice. In contrast, the DAI value was significantly reduced in rCsStefin-1-treated mice than DSS only-treated mice. In addition, the colon length of DSS only-treated mice was shorter than that of rCsStefin-1 treated mice. The secretion levels of IFN-${\gamma}$ and TNF-${\alpha}$ in the spleen and mesenteric lymph nodes (MLNs) were significantly increased by DSS treatment, but the level of TNF-${\alpha}$ in MLNs was significantly decreased by rCsStefin-1 treatment. IL-10 production in both spleen and MLNs was significantly increased, and IL-$10^+F4/80^+$ macrophage cells were significantly increased in the spleen and MLNs of rCsStefin-1 treated mice after DSS treatment. In conclusion, rCsStefin-1 could reduce the intestinal inflammation occurring after DSS treatment, these effects might be related with recruitment of IL-10 secreting macrophages.