Objective： To analyze the immunological characteristics of 2,4,6-trinitrobenzene sulfonic acid（TNBS）-induced colitis model and examine the therapeutic effects and mechanisms of Astragalus polysaccharides（APS） tre...Objective： To analyze the immunological characteristics of 2,4,6-trinitrobenzene sulfonic acid（TNBS）-induced colitis model and examine the therapeutic effects and mechanisms of Astragalus polysaccharides（APS） treatment. Methods： Thirty-two male specific pathogen free Spragne-Dawley rats were randomly equally assigned to four groups： control, TNBS, APS and prednisone groups. Experimental colitis was induced by enema administration of TNBS. Then rats were treated with APS（0.5 g·kg^（-1）·day^（-1）, once daily） or prednisone（1.0 mg·kg^（-1）·day^（-1）, once daily） by gavage for 14 days. Macroscopic lesion and histological damage were determined, and activity of myeloperoxidase（MPO） was measured in the colonic tissues. Expressions of T-box expressed in T-cells（T-bet） and GATA-binding protein-3（GATA-3） were determined by immunohistochemistry analysis and western blot. Results： Both macroscopic lesion and histological colonic damage induced by TNBS were reduced by APS and prednisone treatment. These were accompanied by significant attenuation of MPO activity（P=0.03）. TNBS intervention enhanced the expression of both GATA-3 and T-bet, but the expression of T-bet was significantly enhanced than that of GATA-3, resulting in significant reduction of GATA-3/T-bet ratio（P=0.025）. APS administration enhanced the expression of T-bet（P=0.04） and GATA-3（P=0.019） in comparison to TNBS group, and resulting in an up-regulated GATA-3/T-bet ratio. Prednisone treatment inhibited both expressions; however it also resulted in up-regulation of the GATA-3/T-bet ratio. Conclusions： These results demonstrated that APS exerted a beneficial immune regulatory effect on experimental colitis. It promoted the expression of T helper cell 1（Th1） and T helper cell 2（Th2） specific transcription factors but ultimately favor a shift toward Th2 phenotype, suggesting that APS possessed therapeutic potential in experimental colitis.展开更多
The ultrafine 1,3,5-triamino-2,4,6-trinitrobenzene （TATB） has been prepared by using solvent and non-solvent method, and the influencing factors in close relationship with the grain size and crystal morphology contr...The ultrafine 1,3,5-triamino-2,4,6-trinitrobenzene （TATB） has been prepared by using solvent and non-solvent method, and the influencing factors in close relationship with the grain size and crystal morphology control such as categories and dosage of surfactants, volume ratio of solvent to non-solvent have also been considered in this paper. It showed that these factors had remarkable effect on the crystal morphology, particle size and agglomeration during the crystallization process. By using 0.095% （mass percentage） ionic surfactant （S） as the additive and using spray-drops feeding device as the dropping equipment, 1.06 g TATB raw materials have been refined into free-running ellipsoid and spherical TATB grains with the grain size from 30 to 50 nm. By using 0.014% （mass percentage） non-ionic surfactant （P） as the additive, spherical TATB grains with the particle diameter of 50 nm and with narrow particle-size distribution have also been obtained. It was shown by the characterizations that the ultrafine particle of TATB had better heat resisting evenness and its 5 seconds ignition point is advanced by 7.5 K.展开更多
Acute and chronic colitis affect a huge proportion of the population world-wide.The etiology of colitis cases can be manifold,and diet can significantly affect onset and outcome of colitis.While many forms of acute co...Acute and chronic colitis affect a huge proportion of the population world-wide.The etiology of colitis cases can be manifold,and diet can significantly affect onset and outcome of colitis.While many forms of acute colitis are easily treatable,chronic forms of colitis such as ulcerative colitis and Crohn’s disease(summarized as inflammatory bowel diseases)are multifactorial with poorly understood pathogenesis.Inflammatory bowel diseases are characterized by exacerbated immune responses causing epithelial dysfunction and bacterial translocation.There is no cure and therapies aim at reducing inflammation and restoring intestinal barrier function.Unfortunately,most drugs can have severe side effects.Changes in diet and inclusion of nutritional supplements have been extensively studied in cell culture and animal models,and some supplements have shown promising results in clinical studies.Most of these nutritional supplements including vitamins,fatty acids and phytochemicals reduce oxidative stress and inflammation and have shown beneficial effects during experimental colitis in rodents induced by dextran sulphate sodium or 2,4,6-trinitrobenzene sulfonic acid,which remain the gold standard in pre-clinical colitis research.Here,we summarize the mechanisms through which such nutritional supplements contribute to epithelial barrier stabilization.展开更多
AIM: To investigate the effect and mechanism of stimulation of the hypothalamic paraventricular nucleus with glutamate acid in rats with ulcerative colitis(UC).METHODS: The rats were anesthetized with 10% chloral hydr...AIM: To investigate the effect and mechanism of stimulation of the hypothalamic paraventricular nucleus with glutamate acid in rats with ulcerative colitis(UC).METHODS: The rats were anesthetized with 10% chloral hydrate via abdominal injection and treated with an equal volume of TNBS + 50% ethanol enema, injected into the upper section of the anus with the tail facing up. Colonic damage scores were calculated after injecting a certain dose of glutamic acid into the paraventricular nucleus(p VN), and the effect of the nucleus tractus solitarius(NTS) and vagus nerve in alleviating UC injury through chemical stimulation of the p VN was observed in rats. Expression changes of C-myc, Apaf-1, caspase-3, interleukin(IL)-6, and IL-17 during the protection against UC injury through chemical stimulation of the p VN in rats were detected by Western blot. Malondialdehyde(MDA) content and superoxide dismutase(SOD) activity in colon tissues of rats were measured by colorimetric methods. RESULTS: Chemical stimulation of the PVN significantly reduced UC in rats in a dose-dependent manner. The protective effects of the chemical stimulationof the p VN on rats with UC were eliminated after chemical damage to the p VN. After glutamate receptor antagonist kynurenic acid was injected into the p VN, the protective effects of the chemical stimulation of the p VN were eliminated in rats with UC. After AVpVl receptor antagonist([Deamino-penl, val4, D-Arg8]-vasopressin) was injected into NTS or bilateral chemical damage to NTS, the protective effect of the chemical stimulation of p VN on UC was also eliminated. After chemical stimulation of the p VN, SOD activity increased, MDA content decreased, C-myc protein expression significantly increased, caspase-3 and Apaf-1 protein expression significantly decreased, and IL-6 and IL-17 expression decreased in colon tissues in rats with UC. CONCLUSION: Chemical stimulation of the hypothalamic p VN provides a protective effect against UC injury in rats. Hypothalamic p VN, NTS and vagus nerve play k展开更多
AIM: To study the effects of Changtai granules (CTG), a traditional compound Chinese medicine, on chronic trinitrobenzene sulfonic acid-induced colitis in rats. METHODS: Healthy adult Sprague-Dawley (SD) rats of both ...AIM: To study the effects of Changtai granules (CTG), a traditional compound Chinese medicine, on chronic trinitrobenzene sulfonic acid-induced colitis in rats. METHODS: Healthy adult Sprague-Dawley (SD) rats of both sexes, weighing 250-300 g, were employed in the present study. The rat colitis models were induced by 2, 4,6-trinitrobenzene sulfonic acid (TNBS) enemas at a concentration of 100 mg/kg in 50% ethanol. The experimental animals were randomly divided into dexamethasone (DX) treatment, CTG treatment, and model control groups, which were intracolicly treated daily with DX (0.2 mg/kg), CTG at doses of 2.9, 5.7 and 11.4 g crude drug/kg, and the equal amount of saline respectively from 6 h following induction of the colitis in rats inflicted with TNBS to the end of study. A normal control group of rats treated without TNBS but saline enema was also included in the study. After 3 wk of treatment, the animals were assessed for colonal inflammatory and ulcerative responses with respect to mortality, frequency of diarrhea, histology and myeloperoxidase activity (MPO).RESULTS: The therapeutic effect of CTG on ulcerative colitis (UC) was better than DX. CTG effectively inhibited the activity of granulocytes, macrophages and monocytes in a dosedependent manner. Also it reduced MPO and formation of inflammation in colonic mucosal tissue. Furthermore, administration of CTG significantly prevented body mass loss and death, and decreased frequency of diarrhea in UC rats, when compared with the model control group rats.CONCLUSION: CTG would prove to be an ideal drug for chronic UC, and is warranted to be studied further.展开更多
AIMTo investigate the protective effect of a recombinant adeno-associated virus carrying thymosin β<sub>4</sub> (AAV-Tβ<sub>4</sub>) on murine colitis via intracolonic a...AIMTo investigate the protective effect of a recombinant adeno-associated virus carrying thymosin β<sub>4</sub> (AAV-Tβ<sub>4</sub>) on murine colitis via intracolonic administration.METHODSAAV-Tβ<sub>4</sub> was prepared and intracolonically used to mediate the secretory expression of Tβ<sub>4</sub> in mouse colons. Dextran sulfate sodium (DSS) was applied to induce the murine ulcerative colitis, and 2,4,6-trinitrobenzene sulfonic acid (TNBS) was used to establish a mouse colitis model resembling Crohn’s disease. The disease severity and colon injuries were observed and graded to reveal the effects of AAV-Tβ<sub>4</sub> on colitis. The activities of myeloperoxidase (MPO) and superoxide dismutase (SOD) and the content of malondialdehyde (MDA) were determined using biochemical assays. Colonic levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-10 were measured using ELISA, and mucosal epithelial cell apoptosis and proliferation were detected by TUNEL assay and immunochemistry, respectively.RESULTSRecombinant AAVs efficiently delivered LacZ and Tβ<sub>4</sub> into the colonic tissues of the mice, and AAV-Tβ<sub>4</sub> led to a strong expression of Tβ<sub>4</sub> in mouse colons. In both the DSS and TNBS colitis models, AAV-Tβ<sub>4</sub>-treated mice displayed distinctly attenuated colon injuries and reduced apoptosis rate of colonic mucosal epithelia. AAV-Tβ<sub>4</sub> significantly reduced inflammatory cell infiltrations and relieved oxidative stress in the inflamed colons of the mice, as evidenced by decreases in MPO activity and MDA content and increases in SOD activity. AAV-Tβ<sub>4</sub> also modulated colonic TNF-α, IL-1β and IL-10 levels and suppressed the compensatory proliferation of colonic epithelial cells in DSS- and TNBS-treated mice.CONCLUSIONTβ<sub>4</sub> exerts a protective effect on murine colitis, indicating that AAV-Tβ<sub>4<展开更多
AIM:To evaluate the potential effectiveness of hydroxynaphthoquinone mixture(HM)in rats with 2,4,6-trinitrobenzene sulfonic acid(TNBS)-induced colitis.METHODS:Colitis was induced by intracolonic administration of TNBS...AIM:To evaluate the potential effectiveness of hydroxynaphthoquinone mixture(HM)in rats with 2,4,6-trinitrobenzene sulfonic acid(TNBS)-induced colitis.METHODS:Colitis was induced by intracolonic administration of TNBS(80 mg/kg,dissolved in 50%ethanol).Rats were treated daily for 7 d with HM(2.5,5,10 mg/kg)and mesalazine 100 mg/kg 24 h after TNBS instillation.Disease progression was monitored daily by observation of clinical signs and body weight change.At the end of the experiment,macroscopic and histopathologic lesions of rats were scored,and myeloperoxidase(MPO)activity was determined.We also determined inflammatory cytokine tumor necrosis factor(TNF)-αlevel by ELISA,Western blotting and immunochemistry to explore the potential mechanisms of HM.RESULTS:After intracolonic instillation of TNBS,animals developed colitis associated with soft stool,diarrhea and marked colonic destruction.Administration of HM significantly attenuated clinical and histopathologic severity of TNBS-induced colitis in a dose-dependent manner.It abrogated body weight loss,diarrhea and inflammation,decreased macroscopic damage score,and improved histological signs,with a significant reduction of inflammatory infiltration,ulcer size and the severity of goblet cell depletion(all P<0.05 vs TNBS alone group).HM could reduce MPO activity.In addition,it also decreased serum TNF-αlevel and down-regulated TNF-αexpression in colonic tissue.This reduction was statistically significant when the dose of HM was 10 mg/kg(P<0.05 vs TNBS alone group),and the effect was comparable to that of mesalazine and showed no apparent adverse effect.The underlying mechanism may be associated with TNF-αinhibition.CONCLUSION:These findings suggest that HM possesses favourable therapeutic action in TNBS-induced colitis,which provides direct pharmacological evidence for its clinical application.展开更多
基金Supported by Doctoral Fund of Ministry of Education of China
文摘Objective： To analyze the immunological characteristics of 2,4,6-trinitrobenzene sulfonic acid（TNBS）-induced colitis model and examine the therapeutic effects and mechanisms of Astragalus polysaccharides（APS） treatment. Methods： Thirty-two male specific pathogen free Spragne-Dawley rats were randomly equally assigned to four groups： control, TNBS, APS and prednisone groups. Experimental colitis was induced by enema administration of TNBS. Then rats were treated with APS（0.5 g·kg^（-1）·day^（-1）, once daily） or prednisone（1.0 mg·kg^（-1）·day^（-1）, once daily） by gavage for 14 days. Macroscopic lesion and histological damage were determined, and activity of myeloperoxidase（MPO） was measured in the colonic tissues. Expressions of T-box expressed in T-cells（T-bet） and GATA-binding protein-3（GATA-3） were determined by immunohistochemistry analysis and western blot. Results： Both macroscopic lesion and histological colonic damage induced by TNBS were reduced by APS and prednisone treatment. These were accompanied by significant attenuation of MPO activity（P=0.03）. TNBS intervention enhanced the expression of both GATA-3 and T-bet, but the expression of T-bet was significantly enhanced than that of GATA-3, resulting in significant reduction of GATA-3/T-bet ratio（P=0.025）. APS administration enhanced the expression of T-bet（P=0.04） and GATA-3（P=0.019） in comparison to TNBS group, and resulting in an up-regulated GATA-3/T-bet ratio. Prednisone treatment inhibited both expressions; however it also resulted in up-regulation of the GATA-3/T-bet ratio. Conclusions： These results demonstrated that APS exerted a beneficial immune regulatory effect on experimental colitis. It promoted the expression of T helper cell 1（Th1） and T helper cell 2（Th2） specific transcription factors but ultimately favor a shift toward Th2 phenotype, suggesting that APS possessed therapeutic potential in experimental colitis.
文摘The ultrafine 1,3,5-triamino-2,4,6-trinitrobenzene （TATB） has been prepared by using solvent and non-solvent method, and the influencing factors in close relationship with the grain size and crystal morphology control such as categories and dosage of surfactants, volume ratio of solvent to non-solvent have also been considered in this paper. It showed that these factors had remarkable effect on the crystal morphology, particle size and agglomeration during the crystallization process. By using 0.095% （mass percentage） ionic surfactant （S） as the additive and using spray-drops feeding device as the dropping equipment, 1.06 g TATB raw materials have been refined into free-running ellipsoid and spherical TATB grains with the grain size from 30 to 50 nm. By using 0.014% （mass percentage） non-ionic surfactant （P） as the additive, spherical TATB grains with the particle diameter of 50 nm and with narrow particle-size distribution have also been obtained. It was shown by the characterizations that the ultrafine particle of TATB had better heat resisting evenness and its 5 seconds ignition point is advanced by 7.5 K.
基金funded by the fund SEP-Cinvestav (Project 108)by Conacyt (284292)the Royal Society (NAF/R1/180017)
文摘Acute and chronic colitis affect a huge proportion of the population world-wide.The etiology of colitis cases can be manifold,and diet can significantly affect onset and outcome of colitis.While many forms of acute colitis are easily treatable,chronic forms of colitis such as ulcerative colitis and Crohn’s disease(summarized as inflammatory bowel diseases)are multifactorial with poorly understood pathogenesis.Inflammatory bowel diseases are characterized by exacerbated immune responses causing epithelial dysfunction and bacterial translocation.There is no cure and therapies aim at reducing inflammation and restoring intestinal barrier function.Unfortunately,most drugs can have severe side effects.Changes in diet and inclusion of nutritional supplements have been extensively studied in cell culture and animal models,and some supplements have shown promising results in clinical studies.Most of these nutritional supplements including vitamins,fatty acids and phytochemicals reduce oxidative stress and inflammation and have shown beneficial effects during experimental colitis in rodents induced by dextran sulphate sodium or 2,4,6-trinitrobenzene sulfonic acid,which remain the gold standard in pre-clinical colitis research.Here,we summarize the mechanisms through which such nutritional supplements contribute to epithelial barrier stabilization.
文摘AIM: To investigate the effect and mechanism of stimulation of the hypothalamic paraventricular nucleus with glutamate acid in rats with ulcerative colitis(UC).METHODS: The rats were anesthetized with 10% chloral hydrate via abdominal injection and treated with an equal volume of TNBS + 50% ethanol enema, injected into the upper section of the anus with the tail facing up. Colonic damage scores were calculated after injecting a certain dose of glutamic acid into the paraventricular nucleus(p VN), and the effect of the nucleus tractus solitarius(NTS) and vagus nerve in alleviating UC injury through chemical stimulation of the p VN was observed in rats. Expression changes of C-myc, Apaf-1, caspase-3, interleukin(IL)-6, and IL-17 during the protection against UC injury through chemical stimulation of the p VN in rats were detected by Western blot. Malondialdehyde(MDA) content and superoxide dismutase(SOD) activity in colon tissues of rats were measured by colorimetric methods. RESULTS: Chemical stimulation of the PVN significantly reduced UC in rats in a dose-dependent manner. The protective effects of the chemical stimulationof the p VN on rats with UC were eliminated after chemical damage to the p VN. After glutamate receptor antagonist kynurenic acid was injected into the p VN, the protective effects of the chemical stimulation of the p VN were eliminated in rats with UC. After AVpVl receptor antagonist([Deamino-penl, val4, D-Arg8]-vasopressin) was injected into NTS or bilateral chemical damage to NTS, the protective effect of the chemical stimulation of p VN on UC was also eliminated. After chemical stimulation of the p VN, SOD activity increased, MDA content decreased, C-myc protein expression significantly increased, caspase-3 and Apaf-1 protein expression significantly decreased, and IL-6 and IL-17 expression decreased in colon tissues in rats with UC. CONCLUSION: Chemical stimulation of the hypothalamic p VN provides a protective effect against UC injury in rats. Hypothalamic p VN, NTS and vagus nerve play k
基金Supported by the Science and Technology Development Fund of Shanghai,No.03DZ19531
文摘AIM: To study the effects of Changtai granules (CTG), a traditional compound Chinese medicine, on chronic trinitrobenzene sulfonic acid-induced colitis in rats. METHODS: Healthy adult Sprague-Dawley (SD) rats of both sexes, weighing 250-300 g, were employed in the present study. The rat colitis models were induced by 2, 4,6-trinitrobenzene sulfonic acid (TNBS) enemas at a concentration of 100 mg/kg in 50% ethanol. The experimental animals were randomly divided into dexamethasone (DX) treatment, CTG treatment, and model control groups, which were intracolicly treated daily with DX (0.2 mg/kg), CTG at doses of 2.9, 5.7 and 11.4 g crude drug/kg, and the equal amount of saline respectively from 6 h following induction of the colitis in rats inflicted with TNBS to the end of study. A normal control group of rats treated without TNBS but saline enema was also included in the study. After 3 wk of treatment, the animals were assessed for colonal inflammatory and ulcerative responses with respect to mortality, frequency of diarrhea, histology and myeloperoxidase activity (MPO).RESULTS: The therapeutic effect of CTG on ulcerative colitis (UC) was better than DX. CTG effectively inhibited the activity of granulocytes, macrophages and monocytes in a dosedependent manner. Also it reduced MPO and formation of inflammation in colonic mucosal tissue. Furthermore, administration of CTG significantly prevented body mass loss and death, and decreased frequency of diarrhea in UC rats, when compared with the model control group rats.CONCLUSION: CTG would prove to be an ideal drug for chronic UC, and is warranted to be studied further.
基金Supported by National Foundation of Natural Sciences,China,No.81300293
文摘AIMTo investigate the protective effect of a recombinant adeno-associated virus carrying thymosin β<sub>4</sub> (AAV-Tβ<sub>4</sub>) on murine colitis via intracolonic administration.METHODSAAV-Tβ<sub>4</sub> was prepared and intracolonically used to mediate the secretory expression of Tβ<sub>4</sub> in mouse colons. Dextran sulfate sodium (DSS) was applied to induce the murine ulcerative colitis, and 2,4,6-trinitrobenzene sulfonic acid (TNBS) was used to establish a mouse colitis model resembling Crohn’s disease. The disease severity and colon injuries were observed and graded to reveal the effects of AAV-Tβ<sub>4</sub> on colitis. The activities of myeloperoxidase (MPO) and superoxide dismutase (SOD) and the content of malondialdehyde (MDA) were determined using biochemical assays. Colonic levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-10 were measured using ELISA, and mucosal epithelial cell apoptosis and proliferation were detected by TUNEL assay and immunochemistry, respectively.RESULTSRecombinant AAVs efficiently delivered LacZ and Tβ<sub>4</sub> into the colonic tissues of the mice, and AAV-Tβ<sub>4</sub> led to a strong expression of Tβ<sub>4</sub> in mouse colons. In both the DSS and TNBS colitis models, AAV-Tβ<sub>4</sub>-treated mice displayed distinctly attenuated colon injuries and reduced apoptosis rate of colonic mucosal epithelia. AAV-Tβ<sub>4</sub> significantly reduced inflammatory cell infiltrations and relieved oxidative stress in the inflamed colons of the mice, as evidenced by decreases in MPO activity and MDA content and increases in SOD activity. AAV-Tβ<sub>4</sub> also modulated colonic TNF-α, IL-1β and IL-10 levels and suppressed the compensatory proliferation of colonic epithelial cells in DSS- and TNBS-treated mice.CONCLUSIONTβ<sub>4</sub> exerts a protective effect on murine colitis, indicating that AAV-Tβ<sub>4<
基金Supported by National Program for Important New Drugs R and D,No.2011ZX9102-006-04Programs for Science and Technology Development and Plan of Yantai,No.2013ZH086
文摘AIM:To evaluate the potential effectiveness of hydroxynaphthoquinone mixture(HM)in rats with 2,4,6-trinitrobenzene sulfonic acid(TNBS)-induced colitis.METHODS:Colitis was induced by intracolonic administration of TNBS(80 mg/kg,dissolved in 50%ethanol).Rats were treated daily for 7 d with HM(2.5,5,10 mg/kg)and mesalazine 100 mg/kg 24 h after TNBS instillation.Disease progression was monitored daily by observation of clinical signs and body weight change.At the end of the experiment,macroscopic and histopathologic lesions of rats were scored,and myeloperoxidase(MPO)activity was determined.We also determined inflammatory cytokine tumor necrosis factor(TNF)-αlevel by ELISA,Western blotting and immunochemistry to explore the potential mechanisms of HM.RESULTS:After intracolonic instillation of TNBS,animals developed colitis associated with soft stool,diarrhea and marked colonic destruction.Administration of HM significantly attenuated clinical and histopathologic severity of TNBS-induced colitis in a dose-dependent manner.It abrogated body weight loss,diarrhea and inflammation,decreased macroscopic damage score,and improved histological signs,with a significant reduction of inflammatory infiltration,ulcer size and the severity of goblet cell depletion(all P<0.05 vs TNBS alone group).HM could reduce MPO activity.In addition,it also decreased serum TNF-αlevel and down-regulated TNF-αexpression in colonic tissue.This reduction was statistically significant when the dose of HM was 10 mg/kg(P<0.05 vs TNBS alone group),and the effect was comparable to that of mesalazine and showed no apparent adverse effect.The underlying mechanism may be associated with TNF-αinhibition.CONCLUSION:These findings suggest that HM possesses favourable therapeutic action in TNBS-induced colitis,which provides direct pharmacological evidence for its clinical application.
