Betaine addition to the diet alleviates intestinal injury in growing rabbits during the summer heat through the AAT/mTOR pathway

Background The aim of this experiment was to investigate the effect of different levels of betaine(Bet)inclusion in the diet on the intestinal health of growing rabbits under summer heat.A total of 100 weaned Qixing meat rabbits aged 35 d with body weight of 748.61±38.59 g were randomly divided into 5 treatment groups:control group(basal diet)and Bet groups(basal diet+0.75,1.0,1.5 or 2.0 g/kg Bet).The average daily temperature in the rabbitry during the experiment was 30.48°C and the relative humidity was 69.44%.Results Dietary addition of Bet had no significant effect on growth performance and health status of growing rabbits(P>0.05),but it increased ileal secretory immunoglobulin A content compared to the control under summer heat(P<0.05).Addition of 0.75 g/kg Bet up-regulated jejunal IL-4,down-regulated ileal TNF-αexpression(P<0.05).The addition of 1.0 g/kg Bet increased the villi height(VH)in the jejunum(P<0.05).Serum glucose levels were reduced,and the expression of SLC6A20 was up-regulated in jejunum and ileum of rabbits fed with 1.5 g/kg Bet(P<0.05).When added at 2.0 g/kg,Bet reduced serum HSP70 content,increased jejunal VH,and up-regulated duodenal SLC7A6,SLC38A2,mTOR and 4EBP-2 expression(P<0.05).Correlation analysis revealed that intestinal mTOR expression was significantly and positively correlated with SLC7A6,SLC38A2,SLC36A1 and IL-4 expression(P<0.05).Conclusions Dietary addition of Bet can up-regulate the expression of anti-inflammatory factors through the AAT/mTOR pathway,improve the intestinal immune function,alleviate intestinal damage in growing rabbits caused by summer heat,and improve intestinal health.

Mesoporous silica nanoparticles with chiral pattern topological structure function as“antiskid tires”on the intestinal mucosa to facilitate oral drugs delivery

The weak adhesion between nanocarriers and the intestinal mucosa was one of the main reasons caused the failure in oral delivery.Inspired by the“antiskid tires”with complex chiral patterns,mesoporous silica nanoparticles AT-R@CMSN exhibiting geometrical chiral structure were designed to improve the surface/interface roughness in nanoscale,and employed as the hosting system for insoluble drugs nimesulide(NMS)and ibuprofen(IBU).Once performing the delivery tasks,AT-R@CMSN with rigid skeleton protected the loaded drug and reduced the irritation of drug on gastrointestinal tract(GIT),while their porous structure deprived drug crystal and improved drug release.More importantly,AT-R@CMSN functioned as“antiskid tire”to produce higher friction on intestinal mucosa and substantively influencedmultiple biological processes,including“contact”,“adhesion”,“retention”,“permeation”and“uptake”,compared to the achiral S@MSN,thereby improving the oral adsorption effectiveness of such drug delivery systems.By engineering AT-R@CMSN to overcome the stability,solubility and permeability bottlenecks of drugs,orally administered NMS or IBU loaded AT-R@CMSN could achieve higher relative bioavailability(705.95%and 444.42%,respectively)and stronger anti-inflammation effect.In addition,AT-R@CMSN displayed favorable biocompatibility and biodegradability.Undoubtedly,the present finding helped to understand the oral adsorption process of nanocarriers,and provided novel insights into the rational design of nanocarriers.

Prospects for the use of olfactory mucosa cells in bioprinting for the treatment of spinal cord injuries

The review focuses on the most important areas of cell therapy for spinal cord injuries.Olfactory mucosa cells are promising for transplantation.Obtaining these cells is safe for patients.The use of olfactory mucosa cells is effective in restoring motor function due to the remyelination and regeneration of axons after spinal cord injuries.These cells express neurotrophic factors that play an important role in the functional recovery of nerve tissue after spinal cord injuries.In addition,it is possible to increase the content of neurotrophic factors,at the site of injury,exogenously by the direct injection of neurotrophic factors or their delivery using gene therapy.The advantages of olfactory mucosa cells,in combination with neurotrophic factors,open up wide possibilities for their application in threedimensional and four-dimensional bioprinting technology treating spinal cord injuries.

Relationship between plasma D(-)-lactate and intestinal damage after severe injuries in rats

AIM To explore the kinetic changes in plasma D(-)- lactate and lipopolyssccharide(LPS)levels,and investigate whether D(-)-lactate could be used as a marker of intestinal injury in rats following gut ischemia/ reperfusion,burn,and acute necrotizing pancreatitis (ANP). METHODS Three models were developed in rats:① gut ischemia/ reperfusion obtained by one hour of superior mesenteric artery occlusion followed by reperfusion;② severe burn injury created by 30% of total body surface area(TBSA)full-thickness scald burn;and ③ ANP induced by continuous inverse infusion of sodium taurocholate and trypsin into main pancreatic duct. Plasma levels of D(-)-lactate in systemic circulation and LPS in portal circulation were measured by enzymatic- spectrophotometric method and limulus amebocyte lysate (LAL)test kit,respectively.Tissue samples of intestine were taken for histological analysis. RESULTS One hour gut ischemia followed by reperfusion injuries resulted in a significant elevation in plasma D(-)- lactate and LPS levels,and there was a significant correlation between the plasma D(-)-lactate and LPS(r =0.719,P<0.05).The plasma concentrations of D(-)- lactate and LPS increased significantly at 6h postburn, and there was also a remarkable correlation between them (r = 0.877,P < 0.01).D(-)-lactate and LPS levels elevated significantly at 2h after ANP,with a similar significant correlation between the two levels(r = 0.798, P < 0.01 ).The desquamation of intestine villi and infiltration of inflammatory cells in the lamina propria were observed in all groups. CONCLUSION The changes of plasma D(-)-lactate levels in systemic blood paralleled with LPS levels in the portal vein blood.The measurement of plasma D(-)-lactate level may be a useful marker to assess the intestinal injury and to monitor an increase of intestinal permeability and endotoxemia following severe injuries in early stage.

The protective effects of Xuebijing injection on intestinal injuries of mice exposed to irradiation

Background:Gastrointestinal(GI)injury is one of the most common side effects of radiotherapy.However,there is no ideal therapy method except for symptomatic treatment in the clinic.Xuebijing(XBJ)is a traditional Chinese medicine,used to treat sepsis by injection.In this study,the protective effects of XBJ on radiation-i nduced intestinal injury(RⅢ)and its mechanism were explored.Methods:The effect of XBJ on survival of irradiated C57BL/6 mice was monitored.Histological changes including the number of crypts and the length of villi were evaluated by H&E.The expression of Lgr5^(+)intestinal stem cells(ISCs),Ki67^(+)cells,villin and lysozymes were examined by immunohistochemistry.The expression of cytokines in the intestinal crypt was detected by RT-PCR.DNA damage and apoptosis rates in the small intestine were also evaluated by immunofluorescence.Results:In the present study,XBJ improved the survival rate of the mice after 8.0and 9.0 Gy total body irradiation(TBI).XBJ attenuated structural damage of the small intestine,maintained regenerative ability and promoted proliferation and differentiation of crypt cells,decreased apoptosis rate and reduced DNA damage in the intestine.Elevation of IL-6 and TNF-α was limited,but IL-1,TNF-β and IL-10 levels were increased in XBJ-treated group after irradiation.The expression of Bax and p53 were decreased after XBJ treatment.Conclusions:Taken together,XBJ provides a protective effect on RⅢby inhibiting inflammation and blocking p53-related apoptosis pathway.

Effects of intestinal mucosal blood flow and motility on intestinal mucosa

AIM： To investigate the role of intestinal mucosal blood flow （IMBF） and motility in the damage of intestinal mucosal barrier in rats with traumatic brain injury. METHODS： Sixty-four healthy male Wistar rats were divided randomly into two groups： traumatic brain injury （TBI） group （n = 32）, rats with traumatic brain injury; and control group （n = 32）, rats with sham-operation. Each group was divided into four subgroups （n = 8） as 6, 12, 24 and 48 h after operation. Intestinal motility was measured by the propulsion ratio of a semi-solid colored marker （carbon-ink）. IMBF was measured with the laser-Doppler technique. Endotoxin and D-xylose levels in plasma were measured to evaluate the change of intestinal mucosal barrier function following TBI. RESULTS： The level of endotoxin was significantly higher in TBI group than in the control group at each time point （0.382 ± 0.014 EU/mL vs 0.102 ± 0.007 EU/mL, 0.466 ± 0.018 EU/mL vs 0.114 ± 0.021 EU/mL, 0.478± 0.029 EU/mL vs 0.112 ±- 0.018 EU/mL and 0.412± 0.036 EU/mL vs 0.108 ±0.011 EU/mL, P 〈 0.05）. D-xylose concentrations in plasma in TBI group were significantly higher than in the control group （6.68 ± 2.37 mmol/L vs 3.66 ±1.07 retool/L, 8.51 ± 2.69 mmol/L vs 3.15 ＋ 0.95 mmol/L, 11.68 ±3.24 mmol/L vs 3.78 ± 1.12 mmol/L and 10.23 ± 2.83 mmol/L vs 3.34 ± 1.23 mmol/L, P 〈 0.05）. The IMBF in TBI group was significantly lower than that in the control group （38.5 ± 2.8 PU vs 45.6 ± 4.6 PU, 25.2 ± 3.1 PU vs 48.2 ± 5.3 PU, 21.5 ± 2.7 PU vs 44.9 ± 2.8 PU, 29. 4 ± 3.8 PU vs 46.7 ± 3.2 PU） （P 〈 0.05）. Significant decelerations of intestinal propulsion ratio in T8I groups were found compared with the control group （0.48% ± 0.06% vs 0.62%± 0.03%, 0.37% ±0.05% vs 0.64% ± 0.01%, 0.39% ± 0.07% vs 0.63% =1= 0.05% and 0.46% ± 0.03% vs 0.65% ± 0.02%） （P 〈 0.05）. CONCLUSION： The intestinal mucosal permeability is increased obviously in TBI rats. Decrease of intestinal motility and IMBF occur early in TBI, both are important pathogenic factors for stress-related damage of the intestinal mucosal barrier in TBI.

Emodin alleviates intestinal mucosal injury in rats with severe acute pancreatitis via the caspase-1 inhibition

BACKGROUND: Emodin, a traditional Chinese medicine, has a therapeutic effect on severe acute pancreatitis (SAP), whereas the underlying mechanism is still unclear. Studies showed that the intestinal mucosa impairment, and subsequent release of endotoxin and proinflammatory cytokines such as IL-1 beta, which further leads to the dysfunction of multiple organs, is the potentially lethal mechanism of SAP. Caspase-1, an IL-1 beta converting enzyme, plays an important role in this cytokine cascade process. Investigation of the effect of emodin on regulating the caspase-1 expression and the release proinflammatory cytokines will help to reveal mechanism of emodin in treating SAP. METHODS: Eighty Sprague-Dawley rats were randomly divided into four groups (n=20 each group): SAP, sham-operated (SO), emodin-treated (EM) and caspase-1 inhibitor-treated (ICE-I) groups. SAP was induced by retrograde infusion of 3.5% sodium taurocholate into the pancreatic duct. Emodin and caspase-1 inhibitor were given 30 minutes before and 12 hours after SAP induction. Serum levels of IL-1 beta, IL-18 and endotoxin, histopathological alteration of pancreas tissues, intestinal mucosa, and the intestinal caspase-1 mRNA and protein expressions were assessed 24 hours after SAP induction. RESULTS: Rats in the SAP group had higher serum levels of IL-1 beta and IL-18 (P<0.05), pancreatic and gut pathological scores (P<0.05), and caspase-1 mRNA and protein expressions (P<0.05) compared with the SO group. Compared with the SAP group, rats in the EM and ICE-I groups had lower IL-1 beta and IL-18 levels (P<0.05), lower pancreatic and gut pathological scores (P<0.05), and decreased expression of intestine caspase-1 mRNA (P<0.05). Ultrastructural analysis by transmission electron microscopy found that rats in the SAP group had vaguer epithelial junctions, more disappeared intercellular joints, and more damaged intracellular organelles compared with those in the SO group or the EM and ICE-I groups. CONCLUSIONS: Emodin alleviated pancreatic and intestinal mucosa injury in experimental SAP. Its mechanism may partly be mediated by the inhibition of caspase-1 and its downstream inflammatory cytokines, including IL-1 beta and IL-18. Our animal data may be applicable in clinical practice.

Changes in intestinal mucosal immune barrier in rats with endotoxemia

AIM： To investigate the dysfunction of the immunological barrier of the intestinal mucosa during endotoxemia and to elucidate the potential mechanism of this dysfunction. METHODS： Male Wistar rats were randomly distributed into two groups： control group and lipopolysaccharide （LPS） group. Endotoxemia was induced by a single caudal venous injection of LPS. Animals were sacrificed in batches 2, 6, 12 and 24 h after LPS infusion. The number of microfold （M）-cells, dendritic cells （DCs）, CD4＋ T cells, CD8＋ T cells, regulatory T （Tr） cells and IgA＋ B cells in the intestinal mucosa were counted after immunohistochemical staining. Apoptotic lymphocytes were counted after TUNEL staining. The levels of interleukin （IL）-4, interferon （IFN）-γ, and forkhead box P3 （Foxp3） in mucosal homogenates were measured by ELISA. The secretory IgA （sIgA） content in the total protein of one milligram of small intestinal mucus was detected using a radioimmunological assay.RESULTS： This research demonstrated that LPS-induced endotoxemia results in small intestinal mucosa injury. The number of M-cells, DCs, CD8~ T cells, and IgA~ B cells were decreased while Tr cell and apoptotic lymphocyte numbers were increased significantly. The number of CD4＋ T cells increased in the early stages and then slightly decreased by 24 h. The level of IL-4 significantly increased in the early stages and then reversed by the end of the study period. The level of IFN-T increased slightly in the early stages and then decreased markedly by the 24 h time point. Level of Foxp3 increased whereas sIgA level decreased.CONCLUSION： Mucosal immune dysfunction forms part of the intestinal barrier injury during endotoxemia. The increased number and function of Tr cells as well as lymphocyte apoptosis result in mucosal immunode- ficiency.

Elevated basal intestinal mucosal cytokine levels in asymptomatic first-degree relatives of patients with Crohn's disease

AIM To determine levels of cytokines incolonic mucosa of asymptomatic first degreerelatives of Crohn’s disease patients.METHODS Cytokines(Interleukin(IL)1-Beta,IL-2,IL-5 and IL-8)were measured using ELISAin biopsy samples of normal looking colonicmucosa of first degree relatives of Crohn’sdisease patients(n = 9)and from normalcontrols(n = 10)with no family history ofCrohn’s disease.RESULTS Asymptomatic first degree relativesof patients with Crohn’s disease had significantlyhigher levels of basal intestinal mucosalcytokines(IL-2,IL-5 and IL-8)than normalcontrols.Whether these increased cytokinelevels serve as phenotypic markers for a geneticpredisposition to developing Crohns diseaselater on,or whether they indicate early(pre-clinical)damage has yet to be further defined.CONCLUSION Asymptomatic first degreerelatives of Crohn’s disease patients have higherlevels of cytokines in their normal-lookingintestinal mucosa compared to normal controls,This supports the hypothesis that increasedcytokines may be a cause or an early event inthe inflammatory cascade of Crohns disease andare not merely a result of the inflammatoryprocess.

Review:Mechanism of acute pancreatitis complicated with injury of intestinal mucosa barrier

Acute pancreatitis (AP) is a common acute abdomen in clinic with a rapid onset and dangerous pathogenetic condition. AP can cause an injury of intestinal mucosa barrier, leading to translocation of bacteria or endotoxin through multiple routes, bacterial translocation (BT), gutorigin endotoxaemia, and secondary infection of pancreatic tissue, and then cause systemic in- flammatory response syndrome (SIRS) or multiple organ dysfunction syndrome (MODS), which are important factors influencing AP’s severity and mortality. Meanwhile, the injury of intestinal mucosa barrier plays a key role in AP’s process. Therefore, it is clinically important to study the relationship between the injury of intestinal mucosa barrier and AP. In addition, many factors such as microcirculation disturbance, ischemical reperfusion injury, excessive release of inflammatory mediators and apoptosis may also play important roles in the damage of intestinal mucosa barrier. In this review, we summarize studies on mechanisms of AP.

Protective effect of clodronate-containing liposomes on intestinal mucosal injury in rats with severe acute pancreatitis

BACKGROUND: Severe acute pancreatitis (SAP) can result in intestinal mucosal injury. This study aimed to demonstrate the protective effect of clodronate-containing liposomes on intestinal mucosal injury in rats with SAP. METHODS: Liposomes containing clodronate or phosphate buffered saline (PBS) were prepared by the thin-film method SAP models were prepared by a uniform injection of sodium taurocholate (2 mL/kg body weight) into the subcapsular space of the pancreas. Sprague-Dawley rats were randomly divided into a control group (C group), a SAP plus PBS-containing liposomes group (P group) and a SAP plus clodronate-containing liposomes group (T group). At 2 and 6 hours after the establishment of SAP models, 2 mL blood samples were taken from the superior mesenteric vein to measure the contents of serum TNF-α and IL-12. Pathological changes in the intestine and pancreas were observed using hematoxylin and eosin staining, while apoptosis was detected using TUNEL staining. In addition, the macrophage markers cluster of differentiation 68 (CD68) in the intestinal tissue was assessed with immunohistochemistry. RESULTS: At the two time points, the levels of TNF-α and IL-12 in the P group were higher than those in the C group (P<0.05) Compared with the P group, the levels of TNF-α and IL-12 decreased in the T group (P<0.05). The pathological scores of the intestinal mucosa and pancreas in the T group were lower than those of the P group. In the T group, large numbers of TUNEL-positive cells were observed, but none or few in the C and P groups. The number of CD68-positive macrophages decreased in the T group.CONCLUSIONS: Clodronate-containing liposomes have prote- ctive effects against intestinal mucosal injury in rats with SAP. The blockade of macrophages may provide a novel therapeutic strategy in SAP.

Protective effect of rhubarb on barrier of intestinal mucosa

AIM To investigate the mechanism of the rhubarb on gut barrier protection. METHODS The models of gut barrier damage caused by hemorrhagic shock and intraperitoneal endotoxin were used to study the protective effect of rhubarb on the barrier of intestinal mucosa. They were randomly divided into four groups: treatment (rhubarb) group; positive control group; negative control group; placebo treatment group. The concentration of plasma endotoxin, tissue superoxide dismutase and lipoperoxide were measured. The histological analysis was also used. The effect of rhubarb on gut protection was observed. RESULTS The rhubarb could decrease intestinal permeability, attenuate endotoxin absorption within the gut, (the content of endotoxin in serum: shock group 0 557EU/ml±0 069EU/ml vs rhubarb group 0 345EU/ml±0 055EU/ml), obviously decrease the consumption of tissue SOD and the formation of tissue LPO (the content of SOD in serum, intestine and liver: endotoxin group 122 92NU/ml±43 19NU/ml, 292 24NU/ml±88 76NU/ml, 272 70NU/ml±85 79NU/ml vs rhubarb group 312 23NU/ml±54 93NU/ml, 391 09NU/mg±98 16NU/mg, 542 86NU/mg±119 93NU/mg; The content of LPO in intestine and liver: endotoxin group 8 57μmol/L±2 58μmol/L, 86 97μmol/L±46 54μmol/L vs rhubarb group 3 05μmol/L±1 13μmol/L, 13 18μmol/L±19 64μmol/L). Gut histopathology revealed that rhubarb could promote proliferation of gut goblet cells, increase secretion of mucus and protect intestinal mucosa in hemorrhagic shock model. CONCLUSION The mechanism of the rhubarb on gut barrier protection might involve in decreasing intestinal permeability, scavenging oxygen free radicals, promoting proliferation of goblet cells within intestinal mucosa.

Preventive effect of tetramethylpyrazine on intestinal mucosal injury in rats with acute necrotizing pancreatitis

AIM： To evaluate the role of microcirculatory disorder （MCD） and the therapeutic effectiveness ;of tetramethylpyrazine （TMP） on intestinal mucosa injury in rats with acute necrotizing pancreatitis （ANP）.METHODS： A total of 192 Sprague-Dawley rats were randomly divided into three groups： normal control group （C group）, ANP group not treated with TMP （P group）, ANP group treated with TMP （T group）. An ANP model was induced by injection of 50 g/L sodium taurocholate under the pancreatic membrane （4 mL/kg）. C group received isovolumetric injection of 9 g/L physiological saline solution using the same method. T group received injection of TMP （10 mL/kg） via portal vein. Radioactive biomicrosphere technique was used to measure the blood flow at 0.5, 2, 6 and 12 h after the induction of ANP. Samples of pancreas, distal ileum were collected to observe pathological changes using a validated histology score. Intestinal tissues were also used for examination of myeloperoxidase （MPO） expressed intraceUularly in azurophilic granules of neutrophils.RESULTS： The blood flow was significantly lower in P group than in C group （P 〈 0.01）. The pathological changes were aggravated significantly in P group. The longer the time, the severer the pathological changes. The intestinal MPO activities were significantly higher in P group than in C group （P 〈 0.01）. The blood flow of intestine was significantly higher in T group than in P group after 2 h （P 〈 0.01）. The pathological changes were alleviated significantly in T group. MPO activities were significantly lower in T group than in P group （P 〈 0.01 or P 〈 0.05）. There was a negative correlation between intestinal blood flow and MPO activity （r = -0.981, P 〈 0.01） as well as between intestinal blood flow and pathologic scores （r = -0.922, P 〈 0.05）.CONCLUSION： MCD is an important factor for intestinal injury in ANP. TMP can ameliorate the condition of MCD and the damage to pancreas and intestine.

Hypertonic saline resuscitation reduces apoptosis of intestinal mucosa in a rat model of hemorrhagic shock

Objective: To investigate the early effects of hypertonic and isotonic saline solutions on apoptosis of intestinal mucosa in rats with hemorrhagic shock. Methods: A model of rat with severe hemorrhagic shock was established in 21 Sprague-Dawley (SD) rats. The rats were randomly divided into the sham group, normal saline resuscitation (NS) group, and hypertonic saline resuscitation (HTS) group, with 7 in each group. We detected and compared the apoptosis in small intestinal mucosa of rats after hemorrhagic shock and resuscitation by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL), FITC (fluo- rescein-iso-thiocyanate)-Annexin V/PI (propidium iodide) double staining method, and flow cytometry. Results: In the early stage of hemorrhagic shock and resuscitation, marked apoptosis of small intestinal mucosa in the rats of both NS and HTS groups was observed. The numbers of apoptotic cells in these two groups were significantly greater than that in the sham group (P<0.01). In the HTS group, the apoptic cells significantly decreased, compared with the NS group (P<0.01). Conclusion: In this rat model of severe hemorrhagic shock, the HTS resuscitation of small volume is more effective than the NS resuscitation in reducing apoptosis of intestinal mucosa in rats, which may improve the prognosis of trauma.

Lansoprazole ameliorates intestinal mucosal damage induced by ischemia-reperfusion in rats

AIM: To investigate the protective effect of lansoprazoleon ischemia and reperfusion (I/R)-induced rat intestinalmucosal injury in vivo.METHODS: Intestinal damage was induced by clampingboth the superior mesenteric artery and the celiac trunkfor 30 rain followed by reperfusion in male Sprague-Dawleyrats. lansoprazole was given to rats intraperitoneally 1 hbefore vascular clamping.RESULTS: Both the intraluminal hemoglobin and proteinlevels, as indices of mucosal damage, significantlyincreased in I/R-groups comparion with those of sham-operation groups. These increases in intraluminal hemoglobinand protein levels were significantly inhibited by the treatmentwith lansoprazole at a dose of 1 mg/kg. Small intestineexposed to I/R resulted in mucosal inflammation that wascharacterized by significant increases in thiobarbituric acid-reactive substances (TBARS), tissue-associatedmyeloperoxidase activity (MPO), and mucosal content of ratcytokine-induced neutrophil chemoattractant-1 (CINC-1).These increases in TBARS, MPO activities and CINC-1 contentin the intestinal mucosa after I/R were all inhibited bypretreatment with lansoprazole at a dose of 1 mg/kg.Furthermore, the CINC-1 mRNA expression was increasedduring intestinal I/R, and this increase in mRNA expressionwas inhibited by treatment with lansoprazole.CONCLUSION: Lansoprazole inhibits lipid peroxidation andreduces development of intestinal mucosal inflammationinduced by I/R in rats, suggesting that lansoprazole mayhave a therapeutic potential for I/R injury.

Dynamic changes of IL-2/IL-10, sFas and expression of Fas in intestinal mucosa in rats with acute necrotizing pancreatitis

AIM:To investigate dynamic changes of serum IL-2, IL-10, IL-2/IL-10 and sFas in rats with acute necrotizing pancreatitis. To explore the expression of Fas in intestinal mucosa of rats with acute necrotizing pancreatitis (ANP). METHODS:A total of 64 Sprague-Dawley (SD) rats were randomly divided into two groups:normal control group (C group), ANP group (P group). An ANP model was induced by injection of 50 g/L sodium taurocholate under the pancreatic membrane. Normal control group received isovolumetric injection of 9 g/L physiological saline solution using the same method. The blood samples of the rats in each group were obtained via superior mesenteric vein to measure levels of IL-2, IL-10, sFas and calculate the value of IL-2/IL-10. The levels of IL-2, IL-10 and sFas were determined by ELISA. The severity of intestinal mucosal injury was evaluated by pathologic score. The expression of Fas in intestinal mucosal tissue was determined by immunohistochemistry staining. RESULTS:Levels of serum IL-2 were significantly higher in P group than those of C group (2.79 ± 0.51 vs 3.53 ± 0.62, 2.93 ± 0.89 vs 4.35 ± 1.11, 4.81 ± 1.23 vs 6.94 ± 1.55 and 3.41 ± 0.72 vs 4.80 ± 1.10, respectively, P < 0.01, for all) and its reached peak at 6 h. Levels of serum IL-10 were significantly higher in P group than those of C group at 6 h and 12 h (54.61 ± 15.81 vs 47.34 ± 14.62, 141.15 ± 40.21 vs 156.12 ± 43.10, 89.18 ± 32.52 vs 494.98 ± 11.23 and 77.15 ± 22.60 vs 93.28 ± 25.81, respectively, P < 0.01, for all). The values of IL-2/IL-10 were higher significantly in P group than those of C group at 0.5 h and 2 h (0.05 ± 0.01 vs 0.07 ± 0.02 and 0.02 ± 0.01 vs 0.03 ± 0.01, respectively, P < 0.01, for all), and it were significantly lower than those of C group at 6 h (0.05 ± 0.02 vs 0.01 ± 0.01, P < 0.01) and returned to the control level at 12 h (0.04 ± 0.01 vs 0.05 ± 0.02, P > 0.05). In sFas assay, there was no significant difference between P group and C group (3.16 ± 0.75 vs 3.31 ± 0.80, 4.05 ± 1.08 vs 4.32 ± 1.11, 5.93 ± 1.52 vs 5.41 ± 1.47 and 4.62 ± 1.23 vs 4.44 ± 1.16, respectively, P > 0.05, for all). Comparison of P group and C group, the pathological changes were aggravated significantly in P group. Immunohistochemistry staining show the expression of Fas was absent in normal intestinal tissues, however, it gradually increased after induction of pancreatitis in intestinal tissue, then reached their peaks at 12 h.CONCLUSION:Fas were involved in the pathogenesis of pancreatitis associated intestinal injury. The mechanisms of Fas may be associated to Fas mediated T helper cell apoptosis.

Effect of Danshen on apoptosis and NF-кB protein expression of the intestinal mucosa of rats with severe acute pancreatitis or obstructive jaundice

BACKGROUND:Intestinal mucosa injury in cases of severe acute pancreatitis(SAP) or obstructive jaundice(OJ) is one of the main reasons for the accelerated aggravation of these diseases.Besides being an organ to digest and absorb nutrients,the intestine is also a unique immune organ.When SAP and OJ develop,the destruction of the intestinal mucosa barrier is an important contributing factor for the development of bacterial translocation,systemic inflammatory response syndrome,and multiple organ dysfunction syndrome.It is important to protect the intestinal mucosa in the therapy for SAP and OJ.In this study,we determined the effect of Radix Salviae Miltiorrhizae(Danshen) injection on apoptosis and NF-κB P65 protein expression in the intestinal mucosa of rats with SAP or OJ,and explored the protective mechanism of Danshen in their mucosa.METHODS:Sprague-Dawley rats were used in the SAP and OJ experiments.These rats were randomly divided into shamoperated,model control,and treated groups.At various times after operation,the mortality rates were calculated.Subsequently,the rats were killed to assess the pathological changes,the expression levels of Bax and NF-κB proteins,and the apoptosis indices in the intestinal mucosa.RESULTS:Compared to the corresponding model control group,the number of SAP or OJ rats that died in the treated group decreased but showed no statistically significant difference.At all time points after operation,there was no significant difference between the treated and model control groups in the staining intensity as well as the product of staining intensity and positive staining rate of Bax protein in the intestinal mucosa of SAP and OJ rats.At 3 hours after operation,the apoptosis index of the intestinal mucosa of SAP rats in the treated group was lower than that in the model control group(P【0.01).At 12 hours after operation in SAP rats and 28 days after operation in OJ rats,the staining intensity as well as the product of staining intensity and positive staining rate of NF-κB protein of the intestinal mucosa in the treated group were lower than those in the model control group(P【0.01).CONCLUSION:Danshen exerts protective effects on the intestinal mucosa of SAP and OJ rats perhaps by inhibiting apoptosis and down-regulating NF-κB protein.

The effects of PAF antagonist on intestinal mucosal microcirculation after burn in rats

INTRODUCTIONGut originated infection(GOI)has been recognizedas a potential factor for postburn irreversible shock,early sepsis and multiple system organ failure.The intestinal mucosal barrier injury has beenimplicated as the cause of postburn GOI.However,pathogenesis of the lesion is not

Protective effect of Astragalus membranaceus on intestinal mucosa reperfusion injury after hemorrhagic shock in rats

AIM： To study the protective effect of Astragalus rnernbranaceus on intestinal mucosa reperfusion injury and its mechanism after hemorrhagic shock in rats. METHODS： A total of 32 SD rats were randomly divided into four groups （n = 8, each group）： normal group, model group, low dosage group （treated with 10 g/kg Astragalus membranaceus） and high dosage group （treated with 20 g/kg Astragalus membranaceus）. The model of hemorrhagic shock for 60 min and reperfusion for 90 min was established. Therapeutic solution （3 mL） was administrated before reperfusion. At the end of the study, the observed intestinal pathology was analyzed. The blood concentrations of lactic acid （LD）, nitric oxide （NO）, endothelin-1 （ET-1）, malondialdehyde （MDA） and the activity of superoxide dismutase （SOD）, glutathione peroxidase （GSH-PX） in intestinal mucosa were determined. RESULTS： The intestinal mucosa pathology showed severe damage in model group and low dosage group, slight damage in high dosage group and no obvious damage in normal group. The Chiu＇s score in low dose group and high dose group was significantly lower than that in model group. The content of MDA in model group was higher than that in low and high dose groups, while that in high dose group was almost the same as in normal group. The activity of SOD and GSH-PX was the lowest in model group and significantly higher in high dose group than in normal and low dose groups. The concentrations of LD and ET-1 in model group were the highest. The concentrations of NO in model group and low dose group were significantly lower than those in high dose group and normal group. CONCLUSION： High dose Astraga/us membranaeus has much better protective effect on hemorrhagic shockreperfusion injury of intestinal mucosa than low dose Astragalus membranaceus. The mechanism may be that Astragalus membranaceus can improve antioxidative effect and regulate NO/ET level during hemorrhagic reperfusion.

Effects of psychological stress on small intestinal motility and bacteria and mucosa in mice

AIM: To investigate the effects of psychological stress on small intestinal motility and bacteria and mucosa in mice, and to explore the relationship between small intestinal dysfunction and small intestinal motility and bacteria and mucosa under psychological stress. METHODS: Sixty mice were randomly divided into psychological stress group and control group. Each group were subdivided into small intestinal motility group (n= 10), bacteria group (n = 10), and D-xylose administered to stomach group (n= 10). An animal model with psychological stress was established housing the mice with a hungry cat in separate layers of a two-layer cage. A semi-solid colored marker (carbon-ink) was used for monitoring small intestinal transit. The proximal small intestine was harvested under sterile condition and processed for quantitation for aerobes (Escherichia coli) and anaerobes (Lactobacilli). The quantitation of bacteria was expressed as Iog10(colony forming units/g). D-xylose levels in plasma were measured for estimating trie damage of small intestinal mucosa. RESULTS: Small intestinal transit was inhibited (39.80±9.50% vs 58.79±11.47%,P<0.01) in mice after psychological stress, compared with the controls. Psychological stress resulted in quantitative alterations in the aerobes (E.coli). There was an increase in the number of E coli in the proximal small intestinal flora (1.78±0.30 log10(CFU/g) vs 1.37±0.21 log10(CFU/g), P<0.01), and there was decrease in relative proportion of Lactobacilli and E.coli of stressed mice (0.53±0.63 vs 1.14±1.07,P<0.05), while there was no significant difference in the anaerobes (Lactobacilli) between the two groups (2.31±0.70 log10 (CFU/g) vs 2.44±0.37 log10(CFU/g), P>0.05). D-xylose concentrations in plasma in psychological stress mice were significantly higher than those in the control group (2.90±0.89 mmol/L vs 0.97±0.33 mmol/L, P<0.01). CONCLUSION: Small intestinal dysfunction under psychological stress may be related to the small intestinal motility disorder and dysbacteriosis and the damage of mucosa probably caused by psychological stress.