AIM: To determine the time course of intestinal permeability changes to proteolytically-derived bowel peptides in experimental hemorrhagic shock. METHODS: We injected fluorescently-conjugated casein protein into the s...AIM: To determine the time course of intestinal permeability changes to proteolytically-derived bowel peptides in experimental hemorrhagic shock. METHODS: We injected fluorescently-conjugated casein protein into the small bowel of anesthetized Wistar rats prior to induction of experimental hemorrhagic shock. These molecules, which fluoresce when proteolytically cleaved, were used as markers for the ability of proteolytically cleaved intestinal products to access the central circulation. Blood was serially sampled to quantify the relative change in concentration of proteolytically-cleaved particles in the systemic circulation. To provide spatial resolution of their location, particles in the mesenteric microvasculature were imaged using in vivo intravital fluorescent microscopy. The experiments were then repeated using an alternate measurement technique, fluorescein isothiocyanate(FITC)-labeled dextrans 20, to semi-quantitatively verify the ability of bowel-derived low-molecular weight molecules(< 20 k D) to access the central circulation.RESULTS: Results demonstrate a significant increase in systemic permeability to gut-derived peptides within 20 min after induction of hemorrhage(1.11 ± 0.19 vs 0.86 ± 0.07, P < 0.05) compared to control animals. Reperfusion resulted in a second, sustained increase in systemic permeability to gut-derived peptides in hemorrhaged animals compared to controls(1.2 ± 0.18 vs 0.97 ± 0.1, P < 0.05). Intravital microscopy of the mesentery also showed marked accumulation of fluorescent particles in the microcirculation of hemorrhaged animals compared to controls. These results were replicated using FITC dextrans 20 [10.85 ± 6.52 vs 3.38 ± 1.11 fluorescent intensity units(× 105, P < 0.05, hemorrhagic shock vs controls)], confirming that small bowel ischemia in response to experimental hemorrhagic shock results in marked and early increases in gut membrane permeability. CONCLUSION: Increased small bowel permeability in hemorrhagic shock may allow for systemic absorption of otherwise retained proteolytically-generated peptides, with consequent hemodynamic instability and remote organ failure.展开更多
目的:研究阿螺旋霉素[17-(dimethylaminoethylamino)-17-demethoxygeldanamycin hydrochloride,17-DMAG]在葡聚糖硫酸钠(dextran sulphate sodium,DSS)诱导的小鼠溃疡性结肠炎治疗中的作用.方法:C57BL/6小鼠随机分为正常对照组、DSS模...目的:研究阿螺旋霉素[17-(dimethylaminoethylamino)-17-demethoxygeldanamycin hydrochloride,17-DMAG]在葡聚糖硫酸钠(dextran sulphate sodium,DSS)诱导的小鼠溃疡性结肠炎治疗中的作用.方法:C57BL/6小鼠随机分为正常对照组、DSS模型组、磷酸盐缓冲液(phosphate buffer,P B S)治疗组以及17-D M A G治疗组.采用3%D S S连续饮入以复制溃疡性结肠炎小鼠模型.对结肠炎模型小鼠每日腹腔注射17-DMAG[10 mg/(kg?d)]或同体积PBS.观察小鼠体质量、疾病活动度、单位长度结肠质量、结肠病理损伤程度及结肠上皮细胞凋亡情况,以评价17-DMAG对小鼠溃疡性结肠炎病程发展的影响.结果:3%DSS连续饮入5 d后,模型组小鼠较正常对照组小鼠体质量减轻,疾病活动度、单位肠道结肠重量、结肠病理评分及结肠上皮细胞凋亡增加.与PBS治疗组相比,17-DMAG治疗5 d后,结肠炎小鼠体质量降低程度(90.9%±7.78%vs 81%±5.44%,P<0.05)及疾病活动度显著改善(1.8±0.84 vs 4.7±1.21,P<0.05),单位长度结肠质量(4.43 mg/mm±0.16 mg/mm vs 5.71 mg/mm±0.56 mg/mm,P<0.01)及结肠病理评分降低(4.6±1.30 vs 7.4±0.30,P<0.01),结肠上皮细胞凋亡数目(33.2±5.50vs 62.6±9.81,P<0.01)显著减少.结论:17-DMAG可减轻DSS诱导的小鼠溃疡性结肠炎,其可能通过抑制结肠上皮细胞的凋亡而发挥作用.展开更多
Objective:To investigate the impact of the preinduced intestinal heat shock protein 70(HSP70)on the visceral hypersensitivity and abnormal intestinal motility in a post-infectious irritable bowel syndrome(PI-IBS) mous...Objective:To investigate the impact of the preinduced intestinal heat shock protein 70(HSP70)on the visceral hypersensitivity and abnormal intestinal motility in a post-infectious irritable bowel syndrome(PI-IBS) mouse model.Methods:Eighty-four female C57BL/6 mice were randomly assigned to four groups:control group(n=21) and induction+PI-IBS group(n=21),PI-IBS group(n=21) and induction group(n=21).The mice in PI-IBS group were infected in vivo with trichinella spiralis by oral administration.The visceral hypersensitivity and intestinal motility were evaluated respectively with abdominal withdrawal reflex and colon transportation test.The intestinal HSP70 protein and mRNA level was measured by Western blot and realtime PCR.Meanwhile,the intestinal proinflammatory cytokines IL-10 and TNF-α level was detected by ELISA.Results:Compared with their counterparts in PI-IBS group,the animals in the Induction+PI-IBS group show significantly increased intestinal level of HSP70 and obviously ameliorative clinical tigurcs.including abdominal withdrawal reflex score,intestine transportation time and Bristol scores(P<0.05).Meanwhile,the intestinal post-inflammatory cytokines remarkably changed,including increased IL-10 level and decreased TNF-αlevel(P<0.05).Conclusions:Intestinal IISP70 may play a potential protective role through improving the imbalance between the intestinal post-inflammatory and anti-inflammatory cytokines in PI-IBS.展开更多
基金Supported by Career Development Award(CDA2)1IK2BX-001277-01A1 from the Department of Veterans Affairs,Veterans Health Administration,Office of Research and Developmentthe Foundation for Anesthesia Education and Research and the American Society of Critical Care Anesthesiologists and NIH GM085072-06
文摘AIM: To determine the time course of intestinal permeability changes to proteolytically-derived bowel peptides in experimental hemorrhagic shock. METHODS: We injected fluorescently-conjugated casein protein into the small bowel of anesthetized Wistar rats prior to induction of experimental hemorrhagic shock. These molecules, which fluoresce when proteolytically cleaved, were used as markers for the ability of proteolytically cleaved intestinal products to access the central circulation. Blood was serially sampled to quantify the relative change in concentration of proteolytically-cleaved particles in the systemic circulation. To provide spatial resolution of their location, particles in the mesenteric microvasculature were imaged using in vivo intravital fluorescent microscopy. The experiments were then repeated using an alternate measurement technique, fluorescein isothiocyanate(FITC)-labeled dextrans 20, to semi-quantitatively verify the ability of bowel-derived low-molecular weight molecules(< 20 k D) to access the central circulation.RESULTS: Results demonstrate a significant increase in systemic permeability to gut-derived peptides within 20 min after induction of hemorrhage(1.11 ± 0.19 vs 0.86 ± 0.07, P < 0.05) compared to control animals. Reperfusion resulted in a second, sustained increase in systemic permeability to gut-derived peptides in hemorrhaged animals compared to controls(1.2 ± 0.18 vs 0.97 ± 0.1, P < 0.05). Intravital microscopy of the mesentery also showed marked accumulation of fluorescent particles in the microcirculation of hemorrhaged animals compared to controls. These results were replicated using FITC dextrans 20 [10.85 ± 6.52 vs 3.38 ± 1.11 fluorescent intensity units(× 105, P < 0.05, hemorrhagic shock vs controls)], confirming that small bowel ischemia in response to experimental hemorrhagic shock results in marked and early increases in gut membrane permeability. CONCLUSION: Increased small bowel permeability in hemorrhagic shock may allow for systemic absorption of otherwise retained proteolytically-generated peptides, with consequent hemodynamic instability and remote organ failure.
文摘目的:研究阿螺旋霉素[17-(dimethylaminoethylamino)-17-demethoxygeldanamycin hydrochloride,17-DMAG]在葡聚糖硫酸钠(dextran sulphate sodium,DSS)诱导的小鼠溃疡性结肠炎治疗中的作用.方法:C57BL/6小鼠随机分为正常对照组、DSS模型组、磷酸盐缓冲液(phosphate buffer,P B S)治疗组以及17-D M A G治疗组.采用3%D S S连续饮入以复制溃疡性结肠炎小鼠模型.对结肠炎模型小鼠每日腹腔注射17-DMAG[10 mg/(kg?d)]或同体积PBS.观察小鼠体质量、疾病活动度、单位长度结肠质量、结肠病理损伤程度及结肠上皮细胞凋亡情况,以评价17-DMAG对小鼠溃疡性结肠炎病程发展的影响.结果:3%DSS连续饮入5 d后,模型组小鼠较正常对照组小鼠体质量减轻,疾病活动度、单位肠道结肠重量、结肠病理评分及结肠上皮细胞凋亡增加.与PBS治疗组相比,17-DMAG治疗5 d后,结肠炎小鼠体质量降低程度(90.9%±7.78%vs 81%±5.44%,P<0.05)及疾病活动度显著改善(1.8±0.84 vs 4.7±1.21,P<0.05),单位长度结肠质量(4.43 mg/mm±0.16 mg/mm vs 5.71 mg/mm±0.56 mg/mm,P<0.01)及结肠病理评分降低(4.6±1.30 vs 7.4±0.30,P<0.01),结肠上皮细胞凋亡数目(33.2±5.50vs 62.6±9.81,P<0.01)显著减少.结论:17-DMAG可减轻DSS诱导的小鼠溃疡性结肠炎,其可能通过抑制结肠上皮细胞的凋亡而发挥作用.
基金supported by Natural Science Foundation of China Grant(No.81160057):International Science and Technique Corporation Foundation of Hainan Province Grant(No.KJHZ2013-14)
文摘Objective:To investigate the impact of the preinduced intestinal heat shock protein 70(HSP70)on the visceral hypersensitivity and abnormal intestinal motility in a post-infectious irritable bowel syndrome(PI-IBS) mouse model.Methods:Eighty-four female C57BL/6 mice were randomly assigned to four groups:control group(n=21) and induction+PI-IBS group(n=21),PI-IBS group(n=21) and induction group(n=21).The mice in PI-IBS group were infected in vivo with trichinella spiralis by oral administration.The visceral hypersensitivity and intestinal motility were evaluated respectively with abdominal withdrawal reflex and colon transportation test.The intestinal HSP70 protein and mRNA level was measured by Western blot and realtime PCR.Meanwhile,the intestinal proinflammatory cytokines IL-10 and TNF-α level was detected by ELISA.Results:Compared with their counterparts in PI-IBS group,the animals in the Induction+PI-IBS group show significantly increased intestinal level of HSP70 and obviously ameliorative clinical tigurcs.including abdominal withdrawal reflex score,intestine transportation time and Bristol scores(P<0.05).Meanwhile,the intestinal post-inflammatory cytokines remarkably changed,including increased IL-10 level and decreased TNF-αlevel(P<0.05).Conclusions:Intestinal IISP70 may play a potential protective role through improving the imbalance between the intestinal post-inflammatory and anti-inflammatory cytokines in PI-IBS.
