OBJECTIVEThis study aimed to investigate the roles of platelet activating factor (PAF) receptor antagonist in damage to intestinal mucin-2 (MUC2) during endotoxemia on young rats.

METHODSEighteen-day-old Wistar rats were randomized to be treated with lipopolysaccharide (LPS) (5 mg/kg), LPS plus PAF receptor antagonist and normal saline injection (control). PAF receptor antagonist BN52021 5 mg/kg was administered 30 minutes before or after LPS injection (pretreatment group or treatment group). The ileum specimens (n = 8) were harvested at 1.5, 3, 6, 24, 48 and 72 hours after LPS injection. Transmission electron microscopy was used for morphologic evaluation. Immunohistochemistry was used to determine MUC2 in intestinal mucosa.

RESULTSMicrovilli and tight junctions were intact in the control group. Enlargement of tight junctions were seen in the LPS group and microvilli were thin, rare or disrupted, shed. The rough endoplasmic reticulum, mitochondria, and glycogen particles were injured. The changes of the pretreatment and treatment group were slightly milder than that in the LPS group. Ileum of a control rat in which a thin layer of mucus covering the epithelial surface and mucin-containing goblet cells appeared very distended. The experiment group showed a decrease or irregularly distributed membranous mucus expression. The MUC2 content of absorbance significantly decreased in the LPS challenged group compared with that in the control group (P < 0.01), and reached a nadir at 6 hours (0.1841 +/- 0.0047) vs. the control group (0.2091 +/- 0.0060) (P < 0.01). The tendency of the level of MUC2 in the pretreatment and treatment group was the same as that of the LPS group, and the level of MUC2 in the pretreatment and treatment group was higher than that in the LPS group at each time point. ANOVA analysis showed that the inter-group and intra-group difference had statistical significance (P < 0.05).

CONCLUSIONSPAF may play some roles in the injury of intestinal mucus barrier function during endotoxemia. Preventive and remedial use of PAF receptor antagonist BN52021 may relieve intestinal injury.

Animals ; Endotoxemia ; metabolism ; pathology ; Intestinal Mucosa ; drug effects ; metabolism ; pathology ; Mucin-2 ; metabolism ; Platelet Membrane Glycoproteins ; antagonists & inhibitors ; Rats ; Rats, Wistar ; Receptors, G-Protein-Coupled ; antagonists & inhibitors

OBJECTIVETo study the effect of hypoxia on cofilin activation in intestinal epithelial cells and its relation with distribution of tight junction protein zonula occludens 1 (ZO-1).

METHODSThe human intestinal epithelial cell line Caco-2 was used to reproduce monolayer cells. The monolayer-cell specimens were divided into control group (no treatment), hypoxic group ( exposed to hypoxia), and normoxic group (exposed to normoxia) according to the random number table. Western blotting was used to detect the protein expressions of cofilin and phosphorylatedl cofilin (p-cofilin) of cells in normoxic group and hypoxic group exposed to normoxia or hypoxia for 1, 2, 6, 12, and 24 h and control group, with 9 samples in control group and 9 samples at each time point in the other two groups. The other monolayer-cell specimens were divided into hypoxic group (exposed to hypoxia) and control group (no treatment) according to the random number table. Cells in hypoxic group exposed to hypoxia for 1, 2, 6, 12, and 24 h and control group were obtained. Morphology and distribution of F-actin was observd with laser scanning confocal microscopy, the ratio of F-actin to G-actin was determined by fluorescence method, and distribution of ZO-l and cellular morphology were observed with laser scanning confocal microscopy. The sample number of last 3 experiments was respectively 3, 6, and 3 in both hypoxic group (at each time point) and control group. Data were processed with paired ttest, analysis of variance of repeated measurement, and LSD-t test.

RESULTSThe protein expressions of cofilin and p-cofilin of cells between normoxic group exposed to normoxia for 1 to 24 h and control group showed no significant changes (with values from -0.385 to 1.701, t(p-cofilin)values from 0. 040 to 1.538, P values above 0.05). There were no obvious differences in protein expressions of en filmn of cells between hypoxic group exposed to hypoxia for 1 to 24 h and control group ( with values from 1.032 to 2.390, P values above 0.05). Compared with that in control group, the protein expressions of p-cofilin of cells were greatly reduced in hypoxic group exposed to hypoxia for 1 to 24 h (with values from 4.563 to 22.678, P values below 0.01), especially exposed to hypoxia for 24 h. The protein expressions of cofilin of cells between normoxic group and hypoxic group at each time point were close ( with t values from -0.904 to 1.433, P values above 0.05). In hypoxic group, the protein expressions of p-cofilin of cells exposed to hypoxia for 1, 2, 6, 12, and 24 h were 0.87 +/- 08, 0.780 .05, 0.89 +/- 0.07, 0.68+0. 07, and 0.57 +/- 0.06, respectively, significantly lower than those in normoxic group (0.90 +/- 0.07, 0.97 +/- 0.06, 1.00 +/- 0.06, 1.00 +/- 0.05, and 0.99 +/- 0.05, with t values from 3.193 to 16.434, P values below 0.01). In control group, F-actin in the cytoplasm was abundant, most of it was in bunches. The trend of F-actin was disorderly in hypoxic group from being exposed to hypoxia for 1 h, shortened in length or even dissipated. The ratios of F-actin to G-actin of cells in hypoxic group exposed to hypoxia for 12 and 24 h (0.89 +/- 0.12 and 0.84 +/- 0.19) were obviously decreased as compared with that in control group (1. 00, with t values respectively 3. 622 and 3. 577, P values below 0.01). There were no obvious differences in the ratios of F-actin to G-actin of cells between hypoxic group exposed to hypoxia for 1, 2, and 6 h and control group ( with values from 0.447 to 1.526, P values above 0.05). In control group, cells were compact in arrangement, and ZO-1 was distributed continuously along the cytomnembrane. From being exposed to hypoxia for 2 h, cells became irregular in shape in hypoxic group. ZO-1 was distributed in discontinuous fashion along the cytomembrane with breakage in hypoxic group exposed to hypoxia for 24 h.

CONCLUSIONSHypoxia may cause the disorder of dynamic balance between F-actin and G-actin by inducing cofilin activation, which in turn leads to the changes in distribution of tight junction protein ZO-1 in intestinal epithelial cells.

Actin Depolymerizing Factors ; Actins ; Blotting, Western ; Caco-2 Cells ; drug effects ; physiology ; Epithelial Cells ; cytology ; drug effects ; Humans ; Hypoxia ; metabolism ; Intestinal Mucosa ; drug effects ; metabolism ; pathology ; Intestines ; Oxygen ; pharmacology ; Tight Junctions ; drug effects ; metabolism ; Zonula Occludens-1 Protein ; metabolism

OBJECTIVETo detect the expression of proliferating cell nuclear antigen (PCNA) in severely damaged intestinal mucosa due to high-dose 5-FU exposure.

METHODSThirty-two adult C57BL/6J mice were subjected to daily intraperitoneal high-dose 5-FU injection at 150 mg/kg for 5 consecutive days, and on days 1, 3, and 5, the mice were sacrificed to obtain the small intestinal tissue for HE straining and immunohistochemistry for detecting PCNA expression. Another 8 mice with intraperitoneal PBS injection served as the control group.

RESULTSHigh-dose 5-FU exposure of the mice resulted in severe intestinal mucous damage, with complete destruction of the villi and crypts and significantly increased cells positive for PCNA expression (P<0.01).

CONCLUSIONHigh-dose 5-FU treatment can significantly increase the PCNA index, and the cells expressing PCNA can be closely associated with regeneration of the severely damaged mucosa due to the exposure.

Animals ; Antimetabolites, Antineoplastic ; adverse effects ; Fluorouracil ; adverse effects ; Intestinal Mucosa ; drug effects ; metabolism ; pathology ; Intestine, Small ; drug effects ; metabolism ; pathology ; Mice ; Mice, Inbred C57BL ; Proliferating Cell Nuclear Antigen ; metabolism

OBJECTIVETo observe the effects of scorpion and centipede on interleukin (IL)-2, IL-4, IL-10 in the small intestinal mucosa and joint injury of rats with collagen induced arthritis (CIA).

METHODSSixty Wistar rats were randomly divided into 6 groups: the normal control group, the model group, the low dose scorpion and centipede group, the middle dose scorpion and centipede group, the high dose scorpion and centipede group, and the type II collagen treatment group. The joints' volume was measured 40 days after type II collagen (CII) induced rheumatoid arthritis model was established. The joint injury was observed by naked eyes. The expression levels of IL-2, IL-4, and IL-10 in the small intestine tissue homogenate were detected by enzyme linked immunosorbent assay (ELISA).

RESULTSThe joint injury score and volume of two hind limbs were obviously higher in the model group than in the normal control group since the 23rd day (P < 0.01). Rats were accompanied with red, swollen, and deformed foot toes and ankle joints. Walking was even affected. Meanwhile, the joint injury score and volume of two hind limbs were obviously lowered by medicated with 0.4, 0.2, 0.1 g/kg scorpion and centipede, as well as CII on the 32nd day after medication (P <0.05, P < 0.01). The expression levels of IL-2, IL-4, and IL-10 in the small intestine tissue homogenate were obviously lower in the model group than in the normal control group (P < 0.05, P < 0.01). Compared with the model group, only the expression levels of IL-2 and IL-4 in the small intestine tissue homogenate of the high dose scorpion and centipede group and the type II collagen treatment group significantly increased. The expression level of IL-10 significantly increased in the high and middle dose scorpion and centipede groups, as well as the type II collagen treatment group, showing statistical difference (P < 0.05, P < 0.01).

CONCLUSIONSScorpion and centipede could effectively release the joint injury of rats with CIA. Its mechanism might be correlated with increased expression levels of IL-2, IL-4, and IL-10 in the small intestine mucosa.

Animals ; Arthritis, Experimental ; drug therapy ; metabolism ; pathology ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Interleukin-10 ; metabolism ; Interleukin-2 ; metabolism ; Interleukin-4 ; metabolism ; Intestinal Mucosa ; drug effects ; metabolism ; Intestine, Small ; metabolism ; Joints ; metabolism ; pathology ; Rats ; Rats, Wistar ; Scorpions

OBJECTIVETo observe the effects of Qingyi II Recipe (QR) on the intestinal barrier function (IBF) of severe acute pancreatitis (SAP) rats.

METHODSForty-eight SD rats were selected to prepare SAP model. After modeling, they were randomly divided into the model group and the QR treatment group, 24 in each group. Another 8 rats were selected as the sham-operation group. The intervention was started just when they came to resuscitation from anesthesia. Rats in the QR treatment group was administered with QR (1 mL/100 g) by gastrogavage, while an equal volume of normal saline was given to rats in the sham-operation group and the model group by gastrogavage. The gastrogavage was performed once every 6 h. Eight rats were selected from each group 6, 12, and 24 h after intervention. The ascites amount was measured after opening abdomens. The concentrations of serum diamine oxidase (DAO) and D-lactate were measured. Pathological changes of pancreas and ileum were observed. The pathological scoring of the pancreas was performed. The ileum were scanned by electron microscope.

RESULTSThere was no ascites in the sham-operation group. There was no obviously pathological abnormality in the pancreas or ileum. Compared with the sham-operation group, the ascites amount, serum DAO, D-lactate, and pathological scoring all increased at 6 h in the model group, showing statistical difference (P<0.05). In the model group, the serum DAO, D-lactate, and pathological scoring increased gradually at 6 -24 h with statistical difference (P<0.05). Results under microscope showed disarranged structure, interstitial edema, hemorrhage, a large amount of neutrophil infiltration, local foci or lamellar intestinal necrosis. The 24-h ascites amount increased more at 24 h than at 12 h in the model group with statistical difference (P<0.05). The serum D-lactate and patho- logical scoring increased gradually at 6 -24 h in the QR treatment group with statistical difference (P<0.05). The 24-h ascites amount and DAO increased more at 24 h than at 12 h in the model group with statistical difference (P<0.05). Compared with the model group at the same time point, each index decreased at 6 -24 h in the QR treatment group with statistical difference (P<0.05). Results under microscope showed edema and congestion of the intestinal mucosa tissue, little amount of neutrophil infiltration. But the degrees were milder when compared with those of the model group.

CONCLUSIONQR protected IBF of SAP rats.

Animals ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Intestinal Mucosa ; drug effects ; Male ; Pancreatitis ; drug therapy ; metabolism ; pathology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo explore the effects of traditional Chinese herbal medicine Sijunzi decoction on amelioration of postburn intestinal injury in scalded rats.

METHODSOne hundred and eighty Wistar rats were randomly divided into 3 groups, i.e. scald and treatment (T), scald control (S) and normal control (C) groups. The rats in T group were gavaged with the decoction consisting of tangshen, tuckahoe, large head atractylodes rhizome, glycyrrhizic and rhubarb in a dose of 2 ml twice daily, while the rats in C group were just gavaged with the same amount of distilled water. The rats were sacrificed according to the scheduled postburn observation timepoints. The contents of TNF, NO, MDA and ATPase activity in rat plasma and the intestinal mucosa and the S-IgA content in the intestinal mucus were determined respectively. The changes in histopathology of intestinal mucosa were observed. The samples from internal organ tissue and blood were obtained for bacterial culture.

RESULTSThe contents of TNF, NO and MDA in the intestinal mucosa tissue and the rat plasma in scalded rats were lowered significantly by Sijunzi decoction. Furthermore, S-IgA secretion from intestinal mucous cells was maintained by Sijunzi decoction. T cell count was recovered and intestinal mucous barrier injury were lessened, and the bacterial positive rate in the internal organs was decreased.

CONCLUSIONTraditional Chinese herbal medicine Sijunzi decoction might be helpful in alleviation of postburn intestinal injury and in the prevention of intestinal bacterial translocation.

Animals ; Bacterial Translocation ; drug effects ; Burns ; blood ; drug therapy ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Intestinal Mucosa ; metabolism ; pathology ; Intestines ; microbiology ; Male ; Rats ; Rats, Wistar

OBJECTIVETo observe the effects of recombinant human growth hormone (rhGH) on graft structure and recipient protein metabolism in rat small bowel transplantation (SBT) and total parenteral nutrition (TPN) models.

METHODSTwenty recipients of rat allogeneic heterotopic small bowel transplants (SD-->Wistar) were divided into two groups (GH group and control group). Both groups were supported by standard TPN. Acute rejection was suppressed with CsA 10 mg x kg(-1) x d(-1) intramuscularly. All rats in the experimental group received subcutaneous rhGH 1 U x kg(-1) x d(-1) after transplantation. Morphological mucosal indices of transplanted gut and metabolic parameters such as body weight, nitrogen balance, urinary 3-methyl histidine excretion and serum albumin of the recipients were compared between two groups.

RESULTSThe application of rhGH promoted graft recovery significantly compared with standard TPN support alone. On postoperative day 14, all morphological indexes of transplanted gut recovered to the preoperative state. Protein metabolism in the recipient was also significantly improved. rhGH decreased the catabolism of protein, accelerated regaining of positive nitrogen balance and corrected hypoalbuminemia.

CONCLUSIONGH is an effective metabolic intervention in SBT. It may promote the structural repair of the graft and correct the metabolic disturbance. It is useful in improving the outcome of clinical SBT.

Animals ; Body Weight ; drug effects ; Human Growth Hormone ; pharmacology ; Humans ; Intestinal Mucosa ; drug effects ; pathology ; Intestine, Small ; transplantation ; Methylhistidines ; urine ; Nitrogen ; metabolism ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; Recombinant Proteins ; pharmacology ; Serum Albumin ; drug effects ; metabolism

OBJECTIVETo study the effect of NOD2 on colitis pathogenesis in experimental rats, and discuss therapeutical effect and mechanism of kushenin injection (OMT) on colitis in experimental rats.

METHODFourty Sprague-Dawley (SD) rats were randomly divided into four groups: the normal control group, the model group, the SASP group, and the OMT group, with 10 rats in each group. Except the normal control group, models were established in the remaining three groups with TNBS. The OMT group was injected with kushenin injection, the SASP group was orally administered with mesalazine suspension, the model group and the normal group were orally administered with distilled water for 15 days. Colon lesion score and histological score of experimental rats were observed. Expression of NOD2, NF-kappaB p65 protein in rats colonic mucous was detected by immunohistochemistry. Expression of IL-6 in rat colon mucous was detected by ELISA.

RESULTCompared with normal control group, the expression of NOD2, NF-kappaB p65 and IL-6 in colonic mucosa of the model group were significantly increased (P < 0.01). The SASP group and the OMT group showed lower expressions of NOD2, NF-kappaB p65 and IL-6 in colonic mucosa than the model group (P < 0.01, P < 0.05).

CONCLUSIONThe over expression of colonic mucosa proteins NOD2 and NF-kappaB p65 and increasing secretion of IL-6 take part in the appearance and development of ulcerative colitis. OMT can attenuate ulcerative colitis and protect colonic mucosa by inhibiting expression of NOD2, NF-kappaB p65 and decreasing IL-6.

Animals ; Colitis ; metabolism ; pathology ; physiopathology ; prevention & control ; Colon ; drug effects ; metabolism ; pathology ; physiopathology ; Eating ; drug effects ; Gene Expression Regulation ; drug effects ; Injections ; Intestinal Mucosa ; drug effects ; metabolism ; pathology ; physiopathology ; Male ; Nod2 Signaling Adaptor Protein ; metabolism ; Organ Size ; drug effects ; Pterocarpans ; administration & dosage ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Transcription Factor RelA ; metabolism

OBJECTIVETo investigate the effect of Shenfu Injection (SF, ginesenoside and aconite alkaloid) on the apoptosis of intestinal mucosal epithelial cells during ischemia-reperfusion in rats and its potential mechanisms.

METHODSIschemia-reperfusion model was established in rats. Twenty-four rats were divided into 3 groups with 8 rats in each, eg, ischemia-reperfusion (I/R) group, SF-treated group, and control group. In both SF and I/R groups, the superior mesenteric artery was closed with forceps for 1 hour and then reperfused for 2 hours. Either SF (3 ml/kg, SF group) or normal saline (I/R and control groups) was injected intravenously and continuously for 5 ml/kg with a micropump before the superior mesenteric artery was closed. The superior mesenteric artery was not closed for animals in control group. The expression of casapse-3 and Fas, and the level of TNF-alpha and pathological changes of the ileal mucosal tissue were assayed.

RESULTS(1) The number of apoptosis cells increased obviously in I/R group and was significantly higher than that in SF and control groups (P<0.05). (2) The expression of caspase-3, Fas, and TNF-alpha was significantly higher in I/R group than SF and control groups (P<0.01); however, there was not significant difference in the expression of capase-3 between control group and SF group. There was a positive correlation between the expression of caspase-3, Fas, and TNF-alpha, and the number of apoptosis cells. (3) Under light microscope, intestinal mucosal impairment was found milder in SF group than I/R group (P<0.05).

CONCLUSIONSSF can depress the apoptosis of intestinal mucosal epithelial cells during ischemia-reperfusion by restraining the expression of TNF-alpha, Fas, caspase-3, and accordingly alleviate the ischemia and reperfusion injury of intestinal mucosal epithelial cells.

Animals ; Apoptosis ; drug effects ; Caspase 3 ; Caspases ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Epithelial Cells ; pathology ; physiology ; Female ; Intestinal Mucosa ; pathology ; physiopathology ; Male ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; pathology ; physiopathology ; Tumor Necrosis Factor-alpha ; metabolism ; fas Receptor ; metabolism

OBJECTIVETo investigate the β2-adrenoceptor (β2AR)-β-arrestin2-nuclear factor-κB (NF-κB) signal transduction pathway and the intervention effects of oxymatrine in a rat model of ulcerative colitis.

METHODSForty SD rats were randomly divided into four groups, which included the normal control group, the model group, the mesalazine group and the oxymatrine treatment group, with 10 rats per group. Experimental colitis induced with trinitrobenzene sulfonic acid (TNBS) was established in each group except the normal control group. The rats in the oxymatrine treatment group were treated with intramuscular injection of oxymatrine 63 mg/(kg·d) for 15 days and the rats in the mesalazine group were treated with mesalazine solution 0.5 g/(kg·d) by gastric lavage for 15 days. The rats in the normal control group and model group were treated with 3 mL water by gastric lavage for 15 days. Diarrhea and bloody stool were carefully observed. Histological changes in colonic tissue were examined on day 7 in 2 rats per group that were randomly selected. The expression of β2AR, β-arrestin2 and NF-κB p65 in colon tissue and spleen lymphocytes were detected with immunohistochemistry and Western immunoblotting techniques on day 16 after fasting for 24 h. Six rats died of lavage with 2 each in the normal control, the model group and the mesalazine group; and were not included in the analysis.

RESULTSThe rats in the model group suffered from looser stool and bloody purulent stool after modeling. But in the oxymatrine and mesalazine groups, looser stool and bloody purulent stool reduced after treatment. And the colonic wall in the model group was thickened and the colon length shortened. The colon mucosa was congested in multiple areas with edema, erosion, superficial or linear ulcer and scar formation, while the intestinal mucosa injury reduced in the mesalazine and oxymatrine groups (P<0.01). In colonic mucosa and in spleen lymphocytes, compared with the normal control group, the expression of NF-κBp65 were significantly increased (P<0.01) in the model group while the expressions of β 2AR and β-arrestin2 were significantly decreased (P<0.01). Compared with the model group, the expression of NF-κ Bp65 was significantly decreased in the mesalazine group (P<0.01) and oxymatrine treatment group (P<0.01) while the expressions of β2AR and β-arrestin2 were significantly increased (P<0.01). There were no statistically significant differences in the expression of β2AR, β-arrestin2 and NF-κBp65 between the mesalazine group and oxymatrine group (P>0.05).

CONCLUSIONSThe β2AR-β-arrestin2-NF-κB signal transduction pathway participated in the pathologic course of ulcerative colitis. Oxymatrine attenuated ulcerative colitis through regulating the β2AR-β-arrestin2-NF-κB signal transduction pathway.

Alkaloids ; pharmacology ; Animals ; Arrestins ; metabolism ; Colitis, Ulcerative ; drug therapy ; metabolism ; Colon ; drug effects ; pathology ; Intestinal Mucosa ; drug effects ; metabolism ; pathology ; Lymphocytes ; metabolism ; pathology ; Male ; NF-kappa B ; metabolism ; Quinolizines ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Receptors, Adrenergic, beta-2 ; metabolism ; Signal Transduction ; drug effects ; Spleen ; pathology ; beta-Arrestins