AIM:To investigate the role of nuclear factor of activated T cell 2(NFAT2),the major NFAT protein in peripheral T cells,in sustained T cell activation and intractable inflammation in human ulcerative colitis(UC). METH...AIM:To investigate the role of nuclear factor of activated T cell 2(NFAT2),the major NFAT protein in peripheral T cells,in sustained T cell activation and intractable inflammation in human ulcerative colitis(UC). METHODS:We used two-dimensional gel-electrophoresis, immunohistochemistry,double immunohistochemical staining,and confocal microscopy to inspect the expression of NFAT2 in 107,15,48 and 5 cases of UC, Crohn's disease(CD),non-specific colitis,and 5 healthy individuals,respectively. RESULTS:Up-regulation with profound nucleo- translocation/activation of NFAT2 of lamina propria mononuclear cells(LPMC)of colonic mucosa was found specifically in the affected colonic mucosa from patients with UC,as compared to CD or NC(P<0.001,Kruskal- Wallis test).Nucleo-translocation/activation of NFAT2 primarily occurred in CD8+T,but was less prominent in CD4+T cells or CD20+B cells.It was strongly associated with the disease activity,including endoscopic stage (τ=0.2145,P=0.0281)and histologic grade(τ=0.4167, P<0.001). CONCLUSION:We disclose for the first time the nucleo-translocation/activatin of NFAT2 in lamina propria mononuclear cells in ulcerative colitis.Activation of NFAT2 was specific for ulcerative colitis and highly associated with disease activity.Since activation of NFAT2is implicated in an auto-regulatory positive feedback loop of sustained T-cell activation and NFAT proteins play key roles in the calcium/calcineurin signaling pathways,our results not only provide new insights into the mechanism for sustained intractable inflammation,but also suggest the calcium-calcineurin/NFAT pathway as a new therapeutic target for ulcerative colitis.展开更多
Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury.Various calcium channels are involved in cerebral ischemia/reperfusion injury.Cav3.2 channel is a main subtype of T-type ...Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury.Various calcium channels are involved in cerebral ischemia/reperfusion injury.Cav3.2 channel is a main subtype of T-type calcium channels.T-type calcium channel blockers,such as pimozide and mibefradil,have been shown to prevent cerebral ischemia/reperfusion injury-induced brain injury.However,the role of Cav3.2 channels in cerebral ischemia/reperfusion injury remains unclear.Here,in vitro and in vivo models of cerebral ischemia/reperfusion injury were established using middle cerebral artery occlusion in mice and high glucose hypoxia/reoxygenation exposure in primary hippocampal neurons.The results showed that Cav3.2 expression was significantly upregulated in injured hippocampal tissue and primary hippocampal neurons.We further established a Cav3.2 gene-knockout mouse model of cerebral ischemia/reperfusion injury.Cav3.2 knockout markedly reduced infarct volume and brain water content,and alleviated neurological dysfunction after cerebral ischemia/reperfusion injury.Additionally,Cav3.2 knockout attenuated cerebral ischemia/reperfusion injury-induced oxidative stress,inflammatory response,and neuronal apoptosis.In the hippocampus of Cav3.2-knockout mice,calcineurin overexpression offset the beneficial effect of Cav3.2 knockout after cerebral ischemia/reperfusion injury.These findings suggest that the neuroprotective function of Cav3.2 knockout is mediated by calcineurin/nuclear factor of activated T cells 3 signaling.Findings from this study suggest that Cav3.2 could be a promising target for treatment of cerebral ischemia/reperfusion injury.展开更多
Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In...Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s disease.To investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse model.Some amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A interneurons.These results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ peptides.We treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive weeks.We found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model mice.These findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.展开更多
Objective： To investigate the role of peroxisome proliferator-activated receptors δ （PPARδ） in inflammatory reaction and its possible mechanism in adipocyte. Methods：Lentivirus-mediated RNA interference （RNAi）...Objective： To investigate the role of peroxisome proliferator-activated receptors δ （PPARδ） in inflammatory reaction and its possible mechanism in adipocyte. Methods：Lentivirus-mediated RNA interference （RNAi） was used to block the expression of PPARδ in 3T3-L1 cells. In order to induce inflammation in 3T3-L1, cells were stimulated with tumor necrosis factor-α（TNFα, 20 ng/ml） for 4 h. The expression of PPARδ, nuclear factor κB （NFκB） and C reactive protein （CRP） were determined by Western blot analysis. Results：The expression of PPARδ was reduced by 80% after RNAi. Blockage of PPARδ promoted the expression of CRP and NFκB in cells stimulated with TNFα but had no effect on normal cells. Conclusion： PPARδ is involved in inflammatory reaction in adipocyte. Blockage of PPARδ can promote the inflammation mediated by inflammatory factors and increase the expression of NFκB and CRP in 3T3-L1 cells stimulated with TNFα.展开更多
基金a grant from Chang Gung Memorial Hospital,No.CMRPG33074a grant from National Science Council,Taiwan
文摘AIM:To investigate the role of nuclear factor of activated T cell 2(NFAT2),the major NFAT protein in peripheral T cells,in sustained T cell activation and intractable inflammation in human ulcerative colitis(UC). METHODS:We used two-dimensional gel-electrophoresis, immunohistochemistry,double immunohistochemical staining,and confocal microscopy to inspect the expression of NFAT2 in 107,15,48 and 5 cases of UC, Crohn's disease(CD),non-specific colitis,and 5 healthy individuals,respectively. RESULTS:Up-regulation with profound nucleo- translocation/activation of NFAT2 of lamina propria mononuclear cells(LPMC)of colonic mucosa was found specifically in the affected colonic mucosa from patients with UC,as compared to CD or NC(P<0.001,Kruskal- Wallis test).Nucleo-translocation/activation of NFAT2 primarily occurred in CD8+T,but was less prominent in CD4+T cells or CD20+B cells.It was strongly associated with the disease activity,including endoscopic stage (τ=0.2145,P=0.0281)and histologic grade(τ=0.4167, P<0.001). CONCLUSION:We disclose for the first time the nucleo-translocation/activatin of NFAT2 in lamina propria mononuclear cells in ulcerative colitis.Activation of NFAT2 was specific for ulcerative colitis and highly associated with disease activity.Since activation of NFAT2is implicated in an auto-regulatory positive feedback loop of sustained T-cell activation and NFAT proteins play key roles in the calcium/calcineurin signaling pathways,our results not only provide new insights into the mechanism for sustained intractable inflammation,but also suggest the calcium-calcineurin/NFAT pathway as a new therapeutic target for ulcerative colitis.
基金supported by the Natural Science Foundation of Anhui Province of China,No.2208085Y32Scientific Research Plan Project of Anhui Province of China,No.2022AH020076the Chen Xiao-Ping Foundation for the Development of Science and Technology of Hubei Province,No.CXPJJH12000005-07-115(all to CT).
文摘Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury.Various calcium channels are involved in cerebral ischemia/reperfusion injury.Cav3.2 channel is a main subtype of T-type calcium channels.T-type calcium channel blockers,such as pimozide and mibefradil,have been shown to prevent cerebral ischemia/reperfusion injury-induced brain injury.However,the role of Cav3.2 channels in cerebral ischemia/reperfusion injury remains unclear.Here,in vitro and in vivo models of cerebral ischemia/reperfusion injury were established using middle cerebral artery occlusion in mice and high glucose hypoxia/reoxygenation exposure in primary hippocampal neurons.The results showed that Cav3.2 expression was significantly upregulated in injured hippocampal tissue and primary hippocampal neurons.We further established a Cav3.2 gene-knockout mouse model of cerebral ischemia/reperfusion injury.Cav3.2 knockout markedly reduced infarct volume and brain water content,and alleviated neurological dysfunction after cerebral ischemia/reperfusion injury.Additionally,Cav3.2 knockout attenuated cerebral ischemia/reperfusion injury-induced oxidative stress,inflammatory response,and neuronal apoptosis.In the hippocampus of Cav3.2-knockout mice,calcineurin overexpression offset the beneficial effect of Cav3.2 knockout after cerebral ischemia/reperfusion injury.These findings suggest that the neuroprotective function of Cav3.2 knockout is mediated by calcineurin/nuclear factor of activated T cells 3 signaling.Findings from this study suggest that Cav3.2 could be a promising target for treatment of cerebral ischemia/reperfusion injury.
基金supported by the Notional Natural Science Foundation of China,Nos.81371213 and 8107098 7the Natural Science Foundation of Shanghai,No.21ZR1468400 (all to QLY)。
文摘Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s disease.To investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse model.Some amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A interneurons.These results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ peptides.We treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive weeks.We found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model mice.These findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.
文摘Objective： To investigate the role of peroxisome proliferator-activated receptors δ （PPARδ） in inflammatory reaction and its possible mechanism in adipocyte. Methods：Lentivirus-mediated RNA interference （RNAi） was used to block the expression of PPARδ in 3T3-L1 cells. In order to induce inflammation in 3T3-L1, cells were stimulated with tumor necrosis factor-α（TNFα, 20 ng/ml） for 4 h. The expression of PPARδ, nuclear factor κB （NFκB） and C reactive protein （CRP） were determined by Western blot analysis. Results：The expression of PPARδ was reduced by 80% after RNAi. Blockage of PPARδ promoted the expression of CRP and NFκB in cells stimulated with TNFα but had no effect on normal cells. Conclusion： PPARδ is involved in inflammatory reaction in adipocyte. Blockage of PPARδ can promote the inflammation mediated by inflammatory factors and increase the expression of NFκB and CRP in 3T3-L1 cells stimulated with TNFα.
