ABSTRACT
Objective To investigate the assessment methods and mechanisms of nonsteroidal antiinflammatory drugs (NSAID)-induced injury in rat small intestinal epithelial barrier,and to explore the protective effects of mucosal protective agents and antacids on it.Methods A total of 96 rats were evenly divided into the morphologic observation group and the mechanism research group,and 48 in each group.Then each group was evenly divided into eight subgroups:the healthy control group,the model group (model established with indomethacin),the teprenone prevention group,the rabeprazole prevention group,the treatment control group,the teprenone treatment group,the rabeprazole treatment group and the teprenone and rabeprazole combined group (combined group),six in each group.Exfoliated cells gap density of small intestine of each subgroup was determined by confocal laser endomicroscopy.Serum level of tumor necrosis factor-α (TNF-α)was measured with enzyme-linked immunosorbent assay (ELISA). The expression of nuclear factor-κB (NF-κB),caspase-3,zonula occludens-1 (ZO-1 )and occludin at protein level was detected by Western blotting.The LSD-t test or Hamhane′s T2 test was performed for statistical analysis.Results The exfoliated cells gap densities of the teprenone prevention group and the rabeprazole prevention group were (57.43 ± 24.55 )/1 000 and (59.80 ± 21 .14 )/1 000,respectively, which were both lower than that of the model group ((110.93±50.58)/1 000),and the differences were statistically significant (t= 53.50 and 54.13,both P < 0.01 ).The exfoliated cells gap density of the combined group was (40.53 ±15 .39)/1 000,which was lower than that of the treatment control group ((93.80±40.65 )/1 000 ),and the difference was statistically significant (t =44.27,P <0.01 ).The serum levels of TNF-α of the teprenone prevention group and the rabeprazole prevention group were (25 .80±8.97)ng/L and (22.74 ±7.15 )ng/L,repsectively,which were both lower than that of the model group ((44.48 ± 7.42 )ng/L),and the differences were statistically significant (t = 18.68 and 21 .74,both P <0.01 ).The serum level of TNF-αof the combined group ((13.66 ±4.98)ng/L)was lower than that of the treatment control group ((24.67±6.70)ng/L),and the difference was statistically significant (t = 9.02,P < 0.01 ).The caspase-3 levels of teprenone prevention group and rabeprazole prevention group were 1 .47 ±0.35 and 1 .58 ±0.34,and the NF-κB levels of these two groups were 1 .27±0.14 and 1 .21 ± 0.10,respectively.Compared with those of model group (2.44 ± 0.45 and 1 .69±0.13),the differences were statistically significant (t =0.97,0.86,0.42 and 0.48,respectively, all P <0.01 ).The levels of caspase-3 and NF-κB of the combined group were 0.66±0.06 and 0.44 ± 0.21 ,respectively,which were lower than those of the treatment control group,and the differences were statistically significant (t=0.34 and 0.56,both P <0.01).The expressions of occludin at protein level of the teprenone prevention group and the rabeprazole prevention group were 0.69 ±0.16 and 0.74 ±0.11 , and the levels of ZO-1 were 0.81 ± 0.08 and 0.84 ± 0.12.Compared with those of the model group (0.45 ±0.22 and 0.64±0.07 ),the differences were statistically significant (t =0.24,0.29,0.17 and 0.21 ,respectively,all P <0.01 ).The levels of occludin and ZO-1 of the combined group were 2.50 ± 0.46 and 1 .76±0.18,which were higher than those of the treatment control group,and the differences were statistically significant (t =1 .50 and 0.76,both P <0.01 ).Conclusions The exfoliated cells gap density may be a valuable indicator to predict the degree of inflammation response and permeability of epithelial barrier as well as to evaluate efficacy of medication.Teprenone and rabeprazole have prevention and treatment effects on NSAID-induced injury in rat small intestine.
ABSTRACT
Objective To investigate the mechanism of the permeability of intestinal mucosa in the pathogenesis of irritable bowel syndrome (IBS) and the interventional effects of Clostridium butyricum combined with glutamine.Methods According to random number method,fifty BALB/c mice were divided into control group,experimental control group,glutamine group,Clostridium butyricum group and combination group.IBS mice model was established by water-avoidance stress (WAS) experiment.The defecating time of mice and fecal water content were detected by dyed stool after mice gavaged with methylcellulose (1.5％).The pathological injury of intestine was assessed by hematoxylin and eosin staining.The visceral sensitivity was evaluated by colorectal distention test (CRD).The changes of the permeability of intestine was evaluated by detecting the changes of serum D-lactic acid (D-LA),level of diamine oxidase (DAO),expressions of intestinal epithelial cells (IEC) cell tight junction protein (TJ) (occludin-1,claudin-1,zonula occludens-1 (ZOL-1)) at protein level.The interventional effects of Clostridium butyricum combined with glutamine were evaluated.t test was performed for comparison between groups,and analysis of variance was used for comparison among multi-groups.Results Compared with the control group,the defecating time of experimental control group was significantly shorten ((100.40±14.80) min vs (75.88±12.20) min and water content of fecal significantly increased ((54.76±9.98)％ vs (74.95±7.15)％,t =3.692 and 4.023; P=0.002 and 0.002).The lowest threshold of visceral sensitivity significantly decreased ((40.87 ± 4.82) mmHg (1 mmHg=0.133 kPa) vs (27.80±3.18) mmHg; t=8.761,P＜0.01),while the mucosal pathological injury score significantly increased (0.50±0.15 vs2.60±0.97; t＝6.034,P＜0.01).The level of D-LA ((1 476±246.8) ng/L vs (913.6±90.1) ng/L)) and DAO ((3 391.0±256.9) vs (5 096.0±725.2) ng/L) significantly increased (t=40.920 and 29.810; both P＜0.05),and the expression of tight junction protein ZOL-1 (0.165±0.005 vs0.119±0.003),occludin-1 (0.104±0.016 vs 0.022±0.006) significantly decreased (t=19.830 and 19.830; both P＜0.01).Compared with the experimental control group,after intragastric intervention the defecating time of glutamine group,Clostridium butyricum group and combination group increased ((90.50±3.78),(97.56±8.79) and (99.89±11.90) min and water content of fecal decreased ((69.33±6.71)％,(58.07±8.97)％ and (56.74±8.12)％) and the differences were statistically significant (F=10.020 and 8.740; both P＜0.01).The results of Clostridium butyricum group and combination group were good (F=2.481 and 4.874; both P＜0.05).And the lowest threshold of visceral sensitivity significantly increased ((31.80±2.69),(36.04±5.06) and (38.93±3.30) mmHg; F=2.420,P＜0.05),the result of combination group was the best (F=3.550,P＜0.01).Jejunal mucosal injury was significantly reduced (2.00 ± 0.94,1.30 ± 0.68 and 1.30±0.48; F＝11.350,P＜0.01).After intragastric intervention,serum levels of D-LA ((1 370.0± 78.9),(1 066.0±155.5) and (1 039.0±129.0) ng/L) and DAO ((4 808.0±477.4),(3 713.0± 595.0) and (3 725.0±615.9) ng/L) of glutamine group,Clostridium butyricum group and combination group significantly decreased (F＝37.480 and 27.670; both P＜0.01).The level of ZOL-1(0.126± 0.014,0.125±0.006,0.138±0.004) and occludin 1 (0.037±0.013,0.073±0.028,0.078±0.027) of glutamine group,Clostridium butyricum group and combination group significantly increased,and the differences were statistically significant (F=5.867 and 10.630; both P＜0.05).The change of ZOL-1 of combination group was more than that of Clostridium butyricum group (t =5.457,P ＜ 0.05).Conclusions WAS experiment can induce visceral hypersensitivity,increase the permeability of intestine and reduce the function of intestinal epithelial barrier.Clostridium butyricum and glutamine are effective in the recovery of visceral hypersensitivity and the permeability of mucosal epithelia cells.
ABSTRACT
Objective To observe the possible effect of inactivated schistosome ova on the expression of intestinal epithelial tight junctions ZO-1 and Occludin gene in mouse colitis induced by tinitrobenzene sulfonic acid (TNBS) and its mechanism. Methods Fifty mice were divided into control group (group A, n= 10),TNBS plus normal saline(NS) group(group B, n= 20) and TNBS plus inactivated schistosome ova group(group C, n= 20). Group C was exposed to 10 000 freeze-killed schistosome ova by intraperitoneal injection at day 14 and day 3 before colitis induction. Meanwhile,group B was exposed to 1 ml NS by intraperitoneal injection. The mice in group B and C were challenged with 3 mg TNBS to induce colitis. All mice were killed 7-day after colitis induction and assessed with following variables including mortality, pathological change with HE staining of colon.The transcription levels of ZO-1 and Oceludin in colon tissues were examined using Real-time PCR.The expression and distribution of ZO-1 and Occludin proteins were detected by Western blotting and immunohistochemistry. ResultsIn comparison with group B inactivated schistosome ova most effectively reduced the mortality (30% vs 15 %) and histopathologic severity of TNBS-induced colitis (4.21±0.40 vs 1.74±0.10). The transcription levels of ZO-1 and Occludin in group B were decreased compared with those in group A and group C (P<0.01). When compared with group B,group C showed a significant elevation of the alteration of ZO-1, Occludin proteins expression and localization. Conclusion The results clearly show that schistosome ova treatment reduced the severity of experimental colitis through the regulation of tight junction proteins.