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
BACKGROUND Recent studies have demonstrated that dysfunction of the intestinal barrier is a significant contributing factor to the development of severe acute pancreatitis(SAP).A stable intestinal mucosa barrier funct...BACKGROUND Recent studies have demonstrated that dysfunction of the intestinal barrier is a significant contributing factor to the development of severe acute pancreatitis(SAP).A stable intestinal mucosa barrier functions as a major anatomic and functional barrier,owing to the balance between intestinal epithelial cell(IEC)proliferation and apoptosis.There is some evidence that calcium overload may trigger IEC apoptosis and that calcineurin(CaN)/nuclear factor of activated Tcells(NFAT)signaling might play an important role in calcium-mediated apoptosis.AIM To investigate the potential mechanisms underlying the therapeutic effect of Qingyi decoction(QYD)in SAP.METHODS A rat model of SAP was created via retrograde infusion of sodium deoxycholate.Serum levels of amylase,tumor necrosis factor(TNF-α),interleukin(IL)-6,D-lactic acid,and diamine oxidase(DAO);histological changes;and apoptosis of IECs were examined in rats with or without QYD treatment.The expression of the two subunits of CaN and NFAT in intestinal tissue was measured via quantitative realtime polymerase chain reaction and western blotting.For in vitro studies,Caco-2 cells were treated with lipopolysaccharide(LPS)and QYD serum,and then cell viability and intracellular calcium levels were detected.RESULTS Retrograde infusion of sodium deoxycholate increased the severity of pancreatic and intestinal pathology and the levels of serum amylase,TNF-α,and IL-6.Both the indicators of intestinal mucosa damage(D-lactic acid and DAO)and the levels of IEC apoptosis were elevated in the SAP group.QYD treatment reduced the serum levels of amylase,TNF-α,IL-6,D-lactic acid,and DAO and attenuated the histological findings.IEC apoptosis associated with SAP was ameliorated under QYD treatment.In addition,the protein expression levels of the two subunits of CaN were remarkably elevated in the SAP group,and the NFATc3 gene was significantly upregulated at both the transcript and protein levels in the SAP group compared with the control group.QYD significantly restrained CaN and NFATc3 gene expression in the intestine,which was upregulated in the SAP group.Furthermore,QYD serum significantly decreased the LPS-induced elevation in intracellular free Ca^(2+)levels and inhibited cell death.CONCLUSION QYD can exert protective effects against intestinal mucosa damage caused by SAP and the protective effects are mediated,at least partially,by restraining IEC apoptosis via the CaN/NFATc3 pathway.展开更多
Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering ...Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering RNA(siRNA)eukaryotic expression vector targeted transforming growth factor βⅡ receptor(TGF-β RⅡ)was constructed and transfected into T cells.HPDL cells with T cells transfected with siRNA or not were placed in the culture medium that had been added with lipopolysaccharide(LPS)and baicalin.The obtained solution was divided into six groups according to the components(group Ⅰ:HPDL cells+LPS+T cells transfected with siRNA1+baicalin;group Ⅱ:HPDL cells+LPS+T cells transfected with siRNA1;group Ⅲ:HPDL cells+LPS+T cells+baicalin;group Ⅳ:HPDL cells+LPS+T cells;group Ⅴ:HPDL cells+baicalin;group Ⅵ:HPDL cells)and was cultured for 48 hours.RT-PCR was used to observe the effect of baicalin on the expression of OPG-RANKL in HPDL cells.Results The ratio of RANKL/OPG in group Ⅰ was lower than that in group Ⅱ(P<0.01)and higher than that in group Ⅲ(P<0.01);The ratio of RANKL/OPG in group Ⅲ was lower than that in group Ⅳ(P<0.01);the ratio of RANKL/OPG in group Ⅳ was higher than that in group Ⅵ(P<0.01);the ratio of RANKL/OPG in group Ⅴ was lower than that in group Ⅵ(P<0.05).Conclusion ① Baicalin could decrease the ratio of RANKL/OPG in HPDL cells.② The TGF-β signaling transduction plays an important role in the effect of baicalin on the RANKL/OPG ratio in HPDL cells.③ Baicalin acts not only through TGF-β to regulate RANKL/OPG in HPDL cells,but also through other pathways.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
Aim: To investigate the activation of the nuclear factor of activated T cells (NFAT) and its function in the corticosterone (CORT)-induced apoptosis of rat Leydig cells. Methods: NFAT in rat Leydig cells was det...Aim: To investigate the activation of the nuclear factor of activated T cells (NFAT) and its function in the corticosterone (CORT)-induced apoptosis of rat Leydig cells. Methods: NFAT in rat Leydig cells was detected by Western blotting and immunohistochemical staining. Cyclosporin A (CsA) was used to evaluate potential involvement of NFAT in the CORT-induced apoptosis of Leydig cells. Intracellular Ca^2+ was monitored in CORT-treated Leydig cells using Fluo-3/AM. After the Leydig cells were incubated with either CORT or CORT plus CsA for 12 h, the levels of NFAT2 in the nuclei and in the cytoplasm were measured by semi-quantitative Western blotting. The role of NFAT2 in CORT- induced Leydig cell apoptosis was further evaluated by observing the effects of NFAT2 overexpression and the inhibition of NFAT2 activation by CsA on FasL expression and apoptosis. Results: We found that NFAT2 was the predominant isoform in Leydig cells. CsA blocked the CORT-induced apoptosis of the Leydig cells. The intracellular Ca^2+ level in the Leydig cells was significantly increased after the CORT treatment. The CORT increased the level of NFAT2 in the nuclei and decreased its level in the cytoplasm. CsA blocked the CORT-induced nuclear translocation of NFAT2 in the Leydig cells. Both CORT-induced apoptosis and FasL expression in the rat Leydig cells were enhanced by the overexpression of NFAT2 and antagonized by CsA. Conclusion: NFAT2 was activated in CORT-induced Leydig cell apoptosis. The effects of NFAT2 overexpression and the inhibition of NFAT2 activation suggest that NFAT2 may potentially play a pro-apoptotic role in CORT-induced Leydig cell apoptosis through the up-regulation of FasL.展开更多
The transcription factor nuclear factor κB(NF-κB) plays major roles in inflammatory diseases through regulation of inflammation and cell viability.Multiple sclerosis(MS) is a chronic inflammatory demyelinating a...The transcription factor nuclear factor κB(NF-κB) plays major roles in inflammatory diseases through regulation of inflammation and cell viability.Multiple sclerosis(MS) is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system(CNS).It has been shown that NF-κB is activated in multiple cell types in the CNS of MS patients,including T cells,microglia/macrophages,astrocytes,oligodendrocytes,and neurons.Interestingly,data from animal model studies,particularly studies of experimental autoimmune encephalomyelitis,have suggested that NF-κB activation in these individual cell types has distinct effects on the development of MS.In this review,we will cover the current literature on NF-κB and the evidence for its role in the development of MS and its animal model experimental autoimmune encephalomyelitis.展开更多
AIM:To investigate lipopolysaccharide(LPS) related signal transduction in interstitial cells of Cajal(ICCs) from mouse small intestine.METHODS:For this study,primary culture of ICCs was prepared from the small intesti...AIM:To investigate lipopolysaccharide(LPS) related signal transduction in interstitial cells of Cajal(ICCs) from mouse small intestine.METHODS:For this study,primary culture of ICCs was prepared from the small intestine of the mouse.LPS was treated to the cells prior to measurement of the membrane currents by using whole-cell patch clamp technique.Immunocytochemistry was used to examine the expression of the proteins in ICCs.RESULTS:LPS suppressed the pacemaker currents of ICCs and this could be blocked by AH6809,a prostaglandin E2-EP2 receptor antagonist or NG-Nitro-Larginine Methyl Ester,an inhibitor of nitric oxide(NO) synthase.Toll-like receptor 4,inducible NO synthase or cyclooxygenase-2 immunoreactivity by specific antibodies was detected on ICCs.Catalase(antioxidant agent) had no action on LPS-induced action in ICCs.LPS actions were blocked by nuclear factor kB(NF-kB) inhibitor,actinomycin D(a gene transcription inhibitor),PD 98059(a p42/44 mitogen-activated protein kinases inhibitor) or SB 203580 [a p38 mitogen-activated protein kinases(MAPK) inhibitor].SB 203580 also blocked the prostaglandin E2-induced action on pacemaker currents in ICCs but not NO.CONCLUSION:LPS inhibit the pacemaker currents in ICCs via prostaglandin E2-and NO-dependent mechanism through toll-like receptor 4 and suggest that MAPK and NF-kB are implicated in these actions.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
AIM To investigate T-cell activation, the percentage of peripheral T regulatory cells(Tregs), Th17 cells and the circulating cytokine profile in systemic sclerosis(SSc).METHODS We enrolled a total of 24 SSc patients a...AIM To investigate T-cell activation, the percentage of peripheral T regulatory cells(Tregs), Th17 cells and the circulating cytokine profile in systemic sclerosis(SSc).METHODS We enrolled a total of 24 SSc patients and 16 healthy controls in the study and divided the patients as having diffuse cutaneous SSc(dc SSc, n = 13) or limited cutaneous SSc(lc SSc, n = 11). We performed a further subdivision of the patients regarding the stage of the disease-early, intermediate or late. Peripheral venous blood samples were collected from all subjects. We performed flow cytometric analysis of the activationcapacity of T-lymphocytes upon stimulation with PHA-M and of the percentage of peripheral Tregs and Th17 cells in both patients and healthy controls. We used ELISA to quantitate serum levels of human interleukin(IL)-6, IL-10, tissue growth factor-β1(TGF-β1), and IL-17 A.RESULTS We identified a decreased percentage of CD3+CD69+ cells in PHA-stimulated samples from SSc patients in comparison with healthy controls(13.35% ± 2.90% vs 37.03% ± 2.33%, P < 0.001). However, we did not establish a correlation between the down-regulated CD3+CD69+ cells and the clinical subset, nor regarding the stage of the disease. The activated CD4+CD25+ peripheral lymphocytes were represented in decreased percentage in patients when compared to controls(6.30% ± 0.68% vs 9.36% ± 1.08%, P = 0.016). Regarding the forms of the disease, dc SSc patients demonstrated lower frequency of CD4+CD25+ T cells against healthy subjects(5.95% ± 0.89% vs 9.36% ± 1.08%, P = 0.025). With regard to Th17 cells, our patients demonstrated increased percentage in comparison with controls(18.13% ± 1.55% vs 13.73% ± 1.21%, P = 0.031). We detected up-regulated Th17 cells within the lc SSc subset against controls(20.46% ± 2.41% vs 13.73% ± 1.21%, P = 0.025), nevertheless no difference was found between dc SSc and lc SSc patients. Flow cytometric analysis revealed an increased percentage of CD4+CD25-Foxp3+ in dc SSc patients compared to controls(10.94% ± 1.65% vs 6.88% ± 0.91, P = 0.032). Regarding the peripheral cytokine profile, we detected raised levels of IL-6 [2.10(1.05-4.60) pg/m L vs 0.00 pg/m L, P < 0.001], TGF-β1(19.94 ± 3.35 ng/m L vs 10.03 ± 2.25 ng/m L, P = 0.02), IL-10(2.83 ± 0.44 pg/m L vs 0.68 ± 0.51 pg/m L, P = 0.008), and IL-17 A [6.30(2.50-15.60) pg/m L vs 0(0.00-0.05) pg/m L, P < 0.001] in patients when compared to healthy controls. Furthermore, we found increased circulating IL-10, TGF-β, IL-6 and IL-17 A in the lc SSc subset vs control subjects, as it follows: IL-10(3.32 ± 0.59 pg/m L vs 0.68 ± 0.51 pg/m L, P = 0.003), TGF-β1(22.82 ± 4.99 ng/m L vs 10.03 ± 2.25 ng/m L, P = 0.031), IL-6 [2.08(1.51-4.69) pg/m L vs 0.00 pg/m L, P < 0.001], and IL-17 A [14.50(8.55-41.65) pg/m L vs 0.00(0.00-0.05) pg/m L, P < 0.001]. Furthermore, circulating IL-17 A was higher in lc SSc as opposed to dc SSc subset(31.99 ± 13.29 pg/m L vs 7.14 ± 3.01 pg/m L, P = 0.008). Within the dc SSc subset, raised levels of IL-17 A and IL-6 were detected vs healthy controls: IL-17 A [2.60(0.45-9.80) pg/m L vs 0.00(0.00-0.05) pg/m L, P < 0.001], IL-6 [2.80(1.03-7.23) pg/m L vs 0.00 pg/m L, P < 0.001]. Regarding the stages of the disease, TGF-β1 serum levels were increased in early stage against late stage, independently from the SSc phenotype(30.03 ± 4.59 ng/m L vs 13.08 ± 4.50 ng/m L, P = 0.017).CONCLUSION It is likely that the altered percentage of Th17 and CD4+CD25-Fox P3+ cells along with the peripheral cytokine profile in patients with SSc may play a key role in the pathogenesis of the disease.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 National Key R and D Program of China,No.2019YFE0119300National Natural Science Foundation of China,No.82074158+2 种基金Project funded by China Postdoctoral Science Foundation,No.2018M631793Natural Science Foundation of Liaoning Province,No.2019-ZD-0624Dalian Traditional Chinese Medicine-Related Scientific Research Project,No.18Z2002.
文摘BACKGROUND Recent studies have demonstrated that dysfunction of the intestinal barrier is a significant contributing factor to the development of severe acute pancreatitis(SAP).A stable intestinal mucosa barrier functions as a major anatomic and functional barrier,owing to the balance between intestinal epithelial cell(IEC)proliferation and apoptosis.There is some evidence that calcium overload may trigger IEC apoptosis and that calcineurin(CaN)/nuclear factor of activated Tcells(NFAT)signaling might play an important role in calcium-mediated apoptosis.AIM To investigate the potential mechanisms underlying the therapeutic effect of Qingyi decoction(QYD)in SAP.METHODS A rat model of SAP was created via retrograde infusion of sodium deoxycholate.Serum levels of amylase,tumor necrosis factor(TNF-α),interleukin(IL)-6,D-lactic acid,and diamine oxidase(DAO);histological changes;and apoptosis of IECs were examined in rats with or without QYD treatment.The expression of the two subunits of CaN and NFAT in intestinal tissue was measured via quantitative realtime polymerase chain reaction and western blotting.For in vitro studies,Caco-2 cells were treated with lipopolysaccharide(LPS)and QYD serum,and then cell viability and intracellular calcium levels were detected.RESULTS Retrograde infusion of sodium deoxycholate increased the severity of pancreatic and intestinal pathology and the levels of serum amylase,TNF-α,and IL-6.Both the indicators of intestinal mucosa damage(D-lactic acid and DAO)and the levels of IEC apoptosis were elevated in the SAP group.QYD treatment reduced the serum levels of amylase,TNF-α,IL-6,D-lactic acid,and DAO and attenuated the histological findings.IEC apoptosis associated with SAP was ameliorated under QYD treatment.In addition,the protein expression levels of the two subunits of CaN were remarkably elevated in the SAP group,and the NFATc3 gene was significantly upregulated at both the transcript and protein levels in the SAP group compared with the control group.QYD significantly restrained CaN and NFATc3 gene expression in the intestine,which was upregulated in the SAP group.Furthermore,QYD serum significantly decreased the LPS-induced elevation in intracellular free Ca^(2+)levels and inhibited cell death.CONCLUSION QYD can exert protective effects against intestinal mucosa damage caused by SAP and the protective effects are mediated,at least partially,by restraining IEC apoptosis via the CaN/NFATc3 pathway.
基金supported by the Foundation of Stomatology Hospital,Xi'an Jiaotong University
文摘Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering RNA(siRNA)eukaryotic expression vector targeted transforming growth factor βⅡ receptor(TGF-β RⅡ)was constructed and transfected into T cells.HPDL cells with T cells transfected with siRNA or not were placed in the culture medium that had been added with lipopolysaccharide(LPS)and baicalin.The obtained solution was divided into six groups according to the components(group Ⅰ:HPDL cells+LPS+T cells transfected with siRNA1+baicalin;group Ⅱ:HPDL cells+LPS+T cells transfected with siRNA1;group Ⅲ:HPDL cells+LPS+T cells+baicalin;group Ⅳ:HPDL cells+LPS+T cells;group Ⅴ:HPDL cells+baicalin;group Ⅵ:HPDL cells)and was cultured for 48 hours.RT-PCR was used to observe the effect of baicalin on the expression of OPG-RANKL in HPDL cells.Results The ratio of RANKL/OPG in group Ⅰ was lower than that in group Ⅱ(P<0.01)and higher than that in group Ⅲ(P<0.01);The ratio of RANKL/OPG in group Ⅲ was lower than that in group Ⅳ(P<0.01);the ratio of RANKL/OPG in group Ⅳ was higher than that in group Ⅵ(P<0.01);the ratio of RANKL/OPG in group Ⅴ was lower than that in group Ⅵ(P<0.05).Conclusion ① Baicalin could decrease the ratio of RANKL/OPG in HPDL cells.② The TGF-β signaling transduction plays an important role in the effect of baicalin on the RANKL/OPG ratio in HPDL cells.③ Baicalin acts not only through TGF-β to regulate RANKL/OPG in HPDL cells,but also through other pathways.
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Acknowledgment This work was supported by a grant from National Natural Science Foundation of China (30570681).
文摘Aim: To investigate the activation of the nuclear factor of activated T cells (NFAT) and its function in the corticosterone (CORT)-induced apoptosis of rat Leydig cells. Methods: NFAT in rat Leydig cells was detected by Western blotting and immunohistochemical staining. Cyclosporin A (CsA) was used to evaluate potential involvement of NFAT in the CORT-induced apoptosis of Leydig cells. Intracellular Ca^2+ was monitored in CORT-treated Leydig cells using Fluo-3/AM. After the Leydig cells were incubated with either CORT or CORT plus CsA for 12 h, the levels of NFAT2 in the nuclei and in the cytoplasm were measured by semi-quantitative Western blotting. The role of NFAT2 in CORT- induced Leydig cell apoptosis was further evaluated by observing the effects of NFAT2 overexpression and the inhibition of NFAT2 activation by CsA on FasL expression and apoptosis. Results: We found that NFAT2 was the predominant isoform in Leydig cells. CsA blocked the CORT-induced apoptosis of the Leydig cells. The intracellular Ca^2+ level in the Leydig cells was significantly increased after the CORT treatment. The CORT increased the level of NFAT2 in the nuclei and decreased its level in the cytoplasm. CsA blocked the CORT-induced nuclear translocation of NFAT2 in the Leydig cells. Both CORT-induced apoptosis and FasL expression in the rat Leydig cells were enhanced by the overexpression of NFAT2 and antagonized by CsA. Conclusion: NFAT2 was activated in CORT-induced Leydig cell apoptosis. The effects of NFAT2 overexpression and the inhibition of NFAT2 activation suggest that NFAT2 may potentially play a pro-apoptotic role in CORT-induced Leydig cell apoptosis through the up-regulation of FasL.
基金supported by grants from the National Institutes of Health(NS094151 and NS105689)the National Multiple Sclerosis Society(RG5239-A-3)(to WL)
文摘The transcription factor nuclear factor κB(NF-κB) plays major roles in inflammatory diseases through regulation of inflammation and cell viability.Multiple sclerosis(MS) is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system(CNS).It has been shown that NF-κB is activated in multiple cell types in the CNS of MS patients,including T cells,microglia/macrophages,astrocytes,oligodendrocytes,and neurons.Interestingly,data from animal model studies,particularly studies of experimental autoimmune encephalomyelitis,have suggested that NF-κB activation in these individual cell types has distinct effects on the development of MS.In this review,we will cover the current literature on NF-κB and the evidence for its role in the development of MS and its animal model experimental autoimmune encephalomyelitis.
基金Supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education,Science and Technology,No.2012-0001335
文摘AIM:To investigate lipopolysaccharide(LPS) related signal transduction in interstitial cells of Cajal(ICCs) from mouse small intestine.METHODS:For this study,primary culture of ICCs was prepared from the small intestine of the mouse.LPS was treated to the cells prior to measurement of the membrane currents by using whole-cell patch clamp technique.Immunocytochemistry was used to examine the expression of the proteins in ICCs.RESULTS:LPS suppressed the pacemaker currents of ICCs and this could be blocked by AH6809,a prostaglandin E2-EP2 receptor antagonist or NG-Nitro-Larginine Methyl Ester,an inhibitor of nitric oxide(NO) synthase.Toll-like receptor 4,inducible NO synthase or cyclooxygenase-2 immunoreactivity by specific antibodies was detected on ICCs.Catalase(antioxidant agent) had no action on LPS-induced action in ICCs.LPS actions were blocked by nuclear factor kB(NF-kB) inhibitor,actinomycin D(a gene transcription inhibitor),PD 98059(a p42/44 mitogen-activated protein kinases inhibitor) or SB 203580 [a p38 mitogen-activated protein kinases(MAPK) inhibitor].SB 203580 also blocked the prostaglandin E2-induced action on pacemaker currents in ICCs but not NO.CONCLUSION:LPS inhibit the pacemaker currents in ICCs via prostaglandin E2-and NO-dependent mechanism through toll-like receptor 4 and suggest that MAPK and NF-kB are implicated in these actions.
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.
文摘AIM To investigate T-cell activation, the percentage of peripheral T regulatory cells(Tregs), Th17 cells and the circulating cytokine profile in systemic sclerosis(SSc).METHODS We enrolled a total of 24 SSc patients and 16 healthy controls in the study and divided the patients as having diffuse cutaneous SSc(dc SSc, n = 13) or limited cutaneous SSc(lc SSc, n = 11). We performed a further subdivision of the patients regarding the stage of the disease-early, intermediate or late. Peripheral venous blood samples were collected from all subjects. We performed flow cytometric analysis of the activationcapacity of T-lymphocytes upon stimulation with PHA-M and of the percentage of peripheral Tregs and Th17 cells in both patients and healthy controls. We used ELISA to quantitate serum levels of human interleukin(IL)-6, IL-10, tissue growth factor-β1(TGF-β1), and IL-17 A.RESULTS We identified a decreased percentage of CD3+CD69+ cells in PHA-stimulated samples from SSc patients in comparison with healthy controls(13.35% ± 2.90% vs 37.03% ± 2.33%, P < 0.001). However, we did not establish a correlation between the down-regulated CD3+CD69+ cells and the clinical subset, nor regarding the stage of the disease. The activated CD4+CD25+ peripheral lymphocytes were represented in decreased percentage in patients when compared to controls(6.30% ± 0.68% vs 9.36% ± 1.08%, P = 0.016). Regarding the forms of the disease, dc SSc patients demonstrated lower frequency of CD4+CD25+ T cells against healthy subjects(5.95% ± 0.89% vs 9.36% ± 1.08%, P = 0.025). With regard to Th17 cells, our patients demonstrated increased percentage in comparison with controls(18.13% ± 1.55% vs 13.73% ± 1.21%, P = 0.031). We detected up-regulated Th17 cells within the lc SSc subset against controls(20.46% ± 2.41% vs 13.73% ± 1.21%, P = 0.025), nevertheless no difference was found between dc SSc and lc SSc patients. Flow cytometric analysis revealed an increased percentage of CD4+CD25-Foxp3+ in dc SSc patients compared to controls(10.94% ± 1.65% vs 6.88% ± 0.91, P = 0.032). Regarding the peripheral cytokine profile, we detected raised levels of IL-6 [2.10(1.05-4.60) pg/m L vs 0.00 pg/m L, P < 0.001], TGF-β1(19.94 ± 3.35 ng/m L vs 10.03 ± 2.25 ng/m L, P = 0.02), IL-10(2.83 ± 0.44 pg/m L vs 0.68 ± 0.51 pg/m L, P = 0.008), and IL-17 A [6.30(2.50-15.60) pg/m L vs 0(0.00-0.05) pg/m L, P < 0.001] in patients when compared to healthy controls. Furthermore, we found increased circulating IL-10, TGF-β, IL-6 and IL-17 A in the lc SSc subset vs control subjects, as it follows: IL-10(3.32 ± 0.59 pg/m L vs 0.68 ± 0.51 pg/m L, P = 0.003), TGF-β1(22.82 ± 4.99 ng/m L vs 10.03 ± 2.25 ng/m L, P = 0.031), IL-6 [2.08(1.51-4.69) pg/m L vs 0.00 pg/m L, P < 0.001], and IL-17 A [14.50(8.55-41.65) pg/m L vs 0.00(0.00-0.05) pg/m L, P < 0.001]. Furthermore, circulating IL-17 A was higher in lc SSc as opposed to dc SSc subset(31.99 ± 13.29 pg/m L vs 7.14 ± 3.01 pg/m L, P = 0.008). Within the dc SSc subset, raised levels of IL-17 A and IL-6 were detected vs healthy controls: IL-17 A [2.60(0.45-9.80) pg/m L vs 0.00(0.00-0.05) pg/m L, P < 0.001], IL-6 [2.80(1.03-7.23) pg/m L vs 0.00 pg/m L, P < 0.001]. Regarding the stages of the disease, TGF-β1 serum levels were increased in early stage against late stage, independently from the SSc phenotype(30.03 ± 4.59 ng/m L vs 13.08 ± 4.50 ng/m L, P = 0.017).CONCLUSION It is likely that the altered percentage of Th17 and CD4+CD25-Fox P3+ cells along with the peripheral cytokine profile in patients with SSc may play a key role in the pathogenesis of the disease.