Gastric intestinal symptoms common among diabetic patients are often caused by intestinal motility abnormalities related to enteric neuropathy. It has recently been demonstrated that the nitrergic subpopulation of mye...Gastric intestinal symptoms common among diabetic patients are often caused by intestinal motility abnormalities related to enteric neuropathy. It has recently been demonstrated that the nitrergic subpopulation of myenteric neurons are especially susceptible to the development of diabetic neuropathy. Additionally, different susceptibility of nitrergic neurons located in different intestinal segments to diabetic damage and their different levels of responsiveness to insulin treatment have been revealed. These findings indicate the importance of the neuronal microenvironment in the pathogenesis of diabetic nitrergic neuropathy. The main focus of this review therefore was to summarize recent advances related to the diabetes-related selective nitrergic neuropathy and associated motility disturbances. Special attention was given to the findings on capillary endothelium and enteric glial cells. Growing evidence indicates that capillary endothelium adjacent to the myenteric ganglia and enteric glial cells surrounding them are determinative in establishing the ganglionic microenvironment. Additionally, recent advances in the development of new strategies to improve glycemic control in type 1 and type 2 diabetes mellitus are also considered in this review. Finally, looking to the future, the recent and promising results of metagenomics for the characterization of the gut microbiome in health and disease such as diabetes are highlighted.展开更多
目的观察出生后至成年小鼠小肠Cajal间质细胞(interstitial cells of Cajal,ICC)、氮能神经元、胆碱能神经元的发育情况。方法取出生后7d、28d和60d小鼠小肠制作全层铺片,利用(免疫)组织化学等技术分别显示ICC、氮能神经元、胆碱能神经...目的观察出生后至成年小鼠小肠Cajal间质细胞(interstitial cells of Cajal,ICC)、氮能神经元、胆碱能神经元的发育情况。方法取出生后7d、28d和60d小鼠小肠制作全层铺片,利用(免疫)组织化学等技术分别显示ICC、氮能神经元、胆碱能神经元的数量和形态。结果小鼠生后小肠ICC的数量明显增多,但单位面积细胞数量随小肠长度和面积的增加而降低,在生后28d达到成体水平。而氮能神经元和胆碱能神经元的数量生后即达成体水平,随年龄增加仅见神经突起增长、神经纤维增粗以及神经网络的密度变疏等改变。结论小鼠小肠ICC和胃肠壁内的肠神经系统(enteric nervous system,ENS)神经元的发育并非同步,ICC的发育成熟明显晚于ENS,提示出生后早期局部微环境更易影响ICC的发育与成熟,可能与部分婴幼儿胃肠运动功能障碍疾病的发生发展有关。展开更多
AIM To investigate the intestinal segment-specific effects of diabetes and insulin replacement on the density of different subpopulations of submucous neurons. METHODS Ten weeks after the onset of type 1 diabetes samp...AIM To investigate the intestinal segment-specific effects of diabetes and insulin replacement on the density of different subpopulations of submucous neurons. METHODS Ten weeks after the onset of type 1 diabetes samples were taken from the duodenum, ileum and colon of streptozotocin-induce diabetic, insulin-treated diabetic and sex-and age-matched control rats. Whole-mount preparations of submucous plexus were prepared from the different gut segments for quantitative fluorescent immunohistochemistry. The following double-immunostainings were performed: neuronal nitric oxide synthase(n NOS) and Hu C/D, heme oxygenase(HO) 1 and peripherin, as well as HO2 and peripherin. The density of n NOS-, HO1-and HO2-immunoreactive(IR) neurons was determined as a percentage of the total number of submucous neurons. RESULTS The total number of submucous neurons and the proportion of n NOS-, HO1-and HO2-IR subpopulations were not affected in the duodenal ganglia of control, diabetic and insulin-treated rats. While the total neuronal number did not change in either the ileum or the colon, the density of nitrergic neurons exhibited a 2-and 3-fold increase in the diabetic ileum and colon, respectively, which was further enhanced after insulin replacement. The presence of HO1-and HO2-IR submucous neurons was robust in the colon of controls(38.4%-50.8%), whereas it was significantly lower in the small intestinal segments(0.0%-4.2%, P < 0.0001). Under pathophysiological conditions the only alteration detected was an increase in the ileum and a decrease in the colon of the proportion of HO-IR neurons in insulin-treated diabetic animals. CONCLUSION Diabetes and immediate insulin replacement induce the most pronounced region-specific alterations of n NOS-, HO1-and HO2-IR submucous neuronal density in the distal parts of the gut.展开更多
BACKGROUND The mechanisms underlying gastrointestinal(GI)dysmotility with ulcerative colitis(UC)have not been fully elucidated.The enteric nervous system(ENS)plays an essential role in the GI motility.As a vital neuro...BACKGROUND The mechanisms underlying gastrointestinal(GI)dysmotility with ulcerative colitis(UC)have not been fully elucidated.The enteric nervous system(ENS)plays an essential role in the GI motility.As a vital neurotransmitter in the ENS,the gas neurotransmitter nitric oxide(NO)may impact the colonic motility.In this study,dextran sulfate sodium(DSS)-induced UC rat model was used for investigating the effects of NO by examining the effects of rate-limiting enzyme nitric oxide synthase(NOS)changes on the colonic motility as well as the role of the ENS in the colonic motility during UC.AIM To reveal the relationship between the effects of NOS expression changes in NOS-containing nitrergic neurons and the colonic motility in a rat UC model.METHODS Male rats(n=8/each group)were randomly divided into a control(CG),a UC group(EG1),a UC+thrombin derived polypeptide 508 trifluoroacetic acid(TP508TFA;an NOS agonist)group(EG2),and a UC+NG-monomethyl-L-arginine monoacetate(L-NMMA;an NOS inhibitor)group(EG3).UC was induced by administering 5.5%DSS in drinking water without any other treatment(EG1),while the EG2 and EG3 were gavaged with TP508 TFA and L-NMMA,respectively.The disease activity index(DAI)and histological assessment were recorded for each group,whereas the changes in the proportion of colonic nitrergic neurons were counted using immunofluorescence histochemical staining,Western blot,and enzyme linked immunosorbent assay,respectively.In addition,the contractile tension changes in the circular and longitudinal muscles of the rat colon were investigated in vitro using an organ bath system.RESULTS The proportion of NOS-positive neurons within the colonic myenteric plexus(MP),the relative expression of NOS,and the NOS concentration in serum and colonic tissues were significantly elevated in EG1,EG2,and EG3 compared with CG rats.In UC rats,stimulation with agonists and inhibitors led to variable degrees of increase or decrease for each indicator in the EG2 and EG3.When the rats in EGs developed UC,the mean contractio展开更多
目的观察肝衰竭大鼠胃排空及胃窦肌间神经丛胆碱能和氮能神经的变化。方法 40只Wistar大鼠随机分为肝衰竭模型组和对照组,采用葡聚糖蓝-2000为标志物观察大鼠胃排空的变化,应用乙酰胆碱酯酶(AchE)和还原型辅酶Ⅱ硫辛酰胺脱氢酶(NADPH-d...目的观察肝衰竭大鼠胃排空及胃窦肌间神经丛胆碱能和氮能神经的变化。方法 40只Wistar大鼠随机分为肝衰竭模型组和对照组,采用葡聚糖蓝-2000为标志物观察大鼠胃排空的变化,应用乙酰胆碱酯酶(AchE)和还原型辅酶Ⅱ硫辛酰胺脱氢酶(NADPH-d)组织化学染色及肌间神经丛全层铺片技术,观察肝衰竭大鼠胃窦肌间神经丛胆碱能和氮能神经的变化,并进行定量分析。计量资料以均数±标准差(x±s)表示,组间比较采用t检验。结果肝衰竭组大鼠胃排空明显减弱(163.00±25.68 vs 100.00±18.93,P<0.01),胃窦肌间神经丛胆碱能阳性神经元数量减少,神经纤维变细,分布较稀疏,明显低于对照组(t=3.201,P<0.01);氮能神经阳性神经元数量及神经纤维分布明显高于对照组(t=2.912,P<0.01)。结论肝衰竭大鼠胃功能的减退与胃窦肌间神经丛胆碱能神经分布减少及氮能神经分布增加有关。展开更多
Chronic alcohol abuse damages nearly every organ in the body. The harmful effects of ethanol on thebrain, the liver and the pancreas are well documented. Although chronic alcohol consumption causes serious impairments...Chronic alcohol abuse damages nearly every organ in the body. The harmful effects of ethanol on thebrain, the liver and the pancreas are well documented. Although chronic alcohol consumption causes serious impairments also in the gastrointestinal tract like altered motility, mucosal damage, impaired absorption of nu-trients and inflammation, the effects of chronically consumed ethanol on the enteric nervous system are less detailed. While the nitrergic myenteric neurons play an essential role in the regulation of gastrointestinal peristalsis, it was hypothesised, that these neurons are the first targets of consumed ethanol or its metabolites generated in the different gastrointestinal segments. To reinforce this hypothesis the effects of ethanol on the gastrointestinal tract was investigated in different rodent models with quantitative immunohistochemistry, in vivo and in vitro motility measurements, western blot analysis, evaluation of nitric oxide synthase enzyme activity and bio-imaging of nitric oxide synthesis. These results suggest that chronic alcohol consumption did not result significant neural loss, but primarily impaired the nitrergic pathways in gut region-dependent way leading to disturbed gastrointestinal motility. The gut segment-specific differences in the effects of chronic alcohol consumption highlight the significance the ethanol-induced neuronal microenvironment involving oxidative stress and intestinal microbiota.展开更多
基金Supported by Hungarian National Grant Agency, Grant No. F46201 to Bagyánszki M
文摘Gastric intestinal symptoms common among diabetic patients are often caused by intestinal motility abnormalities related to enteric neuropathy. It has recently been demonstrated that the nitrergic subpopulation of myenteric neurons are especially susceptible to the development of diabetic neuropathy. Additionally, different susceptibility of nitrergic neurons located in different intestinal segments to diabetic damage and their different levels of responsiveness to insulin treatment have been revealed. These findings indicate the importance of the neuronal microenvironment in the pathogenesis of diabetic nitrergic neuropathy. The main focus of this review therefore was to summarize recent advances related to the diabetes-related selective nitrergic neuropathy and associated motility disturbances. Special attention was given to the findings on capillary endothelium and enteric glial cells. Growing evidence indicates that capillary endothelium adjacent to the myenteric ganglia and enteric glial cells surrounding them are determinative in establishing the ganglionic microenvironment. Additionally, recent advances in the development of new strategies to improve glycemic control in type 1 and type 2 diabetes mellitus are also considered in this review. Finally, looking to the future, the recent and promising results of metagenomics for the characterization of the gut microbiome in health and disease such as diabetes are highlighted.
基金Supported by the Hungarian Scientific Research Fund,OTKA grant,No.PD 108309(Nikolett Bódi)by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences(Mária Bagyánszki)by the Stipendium Hungaricum Scholarship,No.2015-SH-500041,Tempus Public Foundation(Lalitha Chandrakumar)
文摘AIM To investigate the intestinal segment-specific effects of diabetes and insulin replacement on the density of different subpopulations of submucous neurons. METHODS Ten weeks after the onset of type 1 diabetes samples were taken from the duodenum, ileum and colon of streptozotocin-induce diabetic, insulin-treated diabetic and sex-and age-matched control rats. Whole-mount preparations of submucous plexus were prepared from the different gut segments for quantitative fluorescent immunohistochemistry. The following double-immunostainings were performed: neuronal nitric oxide synthase(n NOS) and Hu C/D, heme oxygenase(HO) 1 and peripherin, as well as HO2 and peripherin. The density of n NOS-, HO1-and HO2-immunoreactive(IR) neurons was determined as a percentage of the total number of submucous neurons. RESULTS The total number of submucous neurons and the proportion of n NOS-, HO1-and HO2-IR subpopulations were not affected in the duodenal ganglia of control, diabetic and insulin-treated rats. While the total neuronal number did not change in either the ileum or the colon, the density of nitrergic neurons exhibited a 2-and 3-fold increase in the diabetic ileum and colon, respectively, which was further enhanced after insulin replacement. The presence of HO1-and HO2-IR submucous neurons was robust in the colon of controls(38.4%-50.8%), whereas it was significantly lower in the small intestinal segments(0.0%-4.2%, P < 0.0001). Under pathophysiological conditions the only alteration detected was an increase in the ileum and a decrease in the colon of the proportion of HO-IR neurons in insulin-treated diabetic animals. CONCLUSION Diabetes and immediate insulin replacement induce the most pronounced region-specific alterations of n NOS-, HO1-and HO2-IR submucous neuronal density in the distal parts of the gut.
基金Supported by National Natural Science Foundation of China,No.31971112Natural Science Foundation of Liaoning Province,No.2021-MS-330Innovation Capability Support Program of Shaanxi,No.2021TD-57.
文摘BACKGROUND The mechanisms underlying gastrointestinal(GI)dysmotility with ulcerative colitis(UC)have not been fully elucidated.The enteric nervous system(ENS)plays an essential role in the GI motility.As a vital neurotransmitter in the ENS,the gas neurotransmitter nitric oxide(NO)may impact the colonic motility.In this study,dextran sulfate sodium(DSS)-induced UC rat model was used for investigating the effects of NO by examining the effects of rate-limiting enzyme nitric oxide synthase(NOS)changes on the colonic motility as well as the role of the ENS in the colonic motility during UC.AIM To reveal the relationship between the effects of NOS expression changes in NOS-containing nitrergic neurons and the colonic motility in a rat UC model.METHODS Male rats(n=8/each group)were randomly divided into a control(CG),a UC group(EG1),a UC+thrombin derived polypeptide 508 trifluoroacetic acid(TP508TFA;an NOS agonist)group(EG2),and a UC+NG-monomethyl-L-arginine monoacetate(L-NMMA;an NOS inhibitor)group(EG3).UC was induced by administering 5.5%DSS in drinking water without any other treatment(EG1),while the EG2 and EG3 were gavaged with TP508 TFA and L-NMMA,respectively.The disease activity index(DAI)and histological assessment were recorded for each group,whereas the changes in the proportion of colonic nitrergic neurons were counted using immunofluorescence histochemical staining,Western blot,and enzyme linked immunosorbent assay,respectively.In addition,the contractile tension changes in the circular and longitudinal muscles of the rat colon were investigated in vitro using an organ bath system.RESULTS The proportion of NOS-positive neurons within the colonic myenteric plexus(MP),the relative expression of NOS,and the NOS concentration in serum and colonic tissues were significantly elevated in EG1,EG2,and EG3 compared with CG rats.In UC rats,stimulation with agonists and inhibitors led to variable degrees of increase or decrease for each indicator in the EG2 and EG3.When the rats in EGs developed UC,the mean contractio
基金This study was supported by IAP grant P5 /20 of the Federal Belgian goverment and FWO grant G.0185.01 (to J.-P.T. and D. A.),and by a concerted research project granted by the Special Research Fund of the University of antwerp (to J.-P.T.)
文摘目的观察肝衰竭大鼠胃排空及胃窦肌间神经丛胆碱能和氮能神经的变化。方法 40只Wistar大鼠随机分为肝衰竭模型组和对照组,采用葡聚糖蓝-2000为标志物观察大鼠胃排空的变化,应用乙酰胆碱酯酶(AchE)和还原型辅酶Ⅱ硫辛酰胺脱氢酶(NADPH-d)组织化学染色及肌间神经丛全层铺片技术,观察肝衰竭大鼠胃窦肌间神经丛胆碱能和氮能神经的变化,并进行定量分析。计量资料以均数±标准差(x±s)表示,组间比较采用t检验。结果肝衰竭组大鼠胃排空明显减弱(163.00±25.68 vs 100.00±18.93,P<0.01),胃窦肌间神经丛胆碱能阳性神经元数量减少,神经纤维变细,分布较稀疏,明显低于对照组(t=3.201,P<0.01);氮能神经阳性神经元数量及神经纤维分布明显高于对照组(t=2.912,P<0.01)。结论肝衰竭大鼠胃功能的减退与胃窦肌间神经丛胆碱能神经分布减少及氮能神经分布增加有关。
基金Supported by The János Bolyai Research Scholarship of the Hungarian Academy of Sciences(Mária Bagyánszki)by the Hungarian Scientific Research Fund,OTKA grant PD 108309(Nikolett Bódi)
文摘Chronic alcohol abuse damages nearly every organ in the body. The harmful effects of ethanol on thebrain, the liver and the pancreas are well documented. Although chronic alcohol consumption causes serious impairments also in the gastrointestinal tract like altered motility, mucosal damage, impaired absorption of nu-trients and inflammation, the effects of chronically consumed ethanol on the enteric nervous system are less detailed. While the nitrergic myenteric neurons play an essential role in the regulation of gastrointestinal peristalsis, it was hypothesised, that these neurons are the first targets of consumed ethanol or its metabolites generated in the different gastrointestinal segments. To reinforce this hypothesis the effects of ethanol on the gastrointestinal tract was investigated in different rodent models with quantitative immunohistochemistry, in vivo and in vitro motility measurements, western blot analysis, evaluation of nitric oxide synthase enzyme activity and bio-imaging of nitric oxide synthesis. These results suggest that chronic alcohol consumption did not result significant neural loss, but primarily impaired the nitrergic pathways in gut region-dependent way leading to disturbed gastrointestinal motility. The gut segment-specific differences in the effects of chronic alcohol consumption highlight the significance the ethanol-induced neuronal microenvironment involving oxidative stress and intestinal microbiota.
