Psoriasis is a chronic autoimmune disease featured by patches on the skin.It is caused by malfunction of immune cells and keratinocytes with inflammation as one of its key features.Apigenin(API)is a natural flavonoid ...Psoriasis is a chronic autoimmune disease featured by patches on the skin.It is caused by malfunction of immune cells and keratinocytes with inflammation as one of its key features.Apigenin(API)is a natural flavonoid with anti-inflammatory and immunoregulatory properties.Therefore,we speculated that API can ameliorate psoriasis,and determined its effect on the development of psoriasis by using imiquimod(IMQ)-induced psoriasis mouse model.Our results showed that API attenuated IMQ-induced phenotypic changes,such as erythema,scaling and epidermal thickening,and improved splenic hyperplasia.Abnormal differentiation of immune cells was restored in API-treated mice.Mechanistically,we revealed that API is a key regulator of signal transducer activator of transcription 3(STAT3).API regulated immune responses by reducing interleukin-23(IL-23)/STAT3/IL-17A axis.Moreover,it suppressed IMQ-caused cell hyperproliferation by inactivating STAT3 through regulation of extracellular signal-regulated kinase 1/2 and nuclear factor-κB(NF-κB)pathway.Furthermore,API reduced expression of inflammatory cytokines through inactivation of NF-κB.Taken together,our study demonstrates that API can ameliorate psoriasis and may be considered as a strategy for psoriasis treatment.展开更多
Inflammation plays an important role in the development of several cancers.Inflammatory cytokines,including tumor necrosis factor-α(TNF-α),are associated with the induction of inflammation.Chronic inflammation contr...Inflammation plays an important role in the development of several cancers.Inflammatory cytokines,including tumor necrosis factor-α(TNF-α),are associated with the induction of inflammation.Chronic inflammation contributes to the progression of cancer through several mechanisms,including increased cytokine production and activation of transcription factors,such as nuclear factor-κB(NF-κB).Zerumbone(ZER),a component of subtropical ginger(Zingiber zerumbet Smith),seems to have anti-inflammatory,anti-cancer,and antioxidant activities.In this study,we aimed to explore the protective function and mechanisms of ZER against TNF-α-induced cancer-promoting cytokines.We found that the viability of stimulated human fibroblast cell lines was reduced after treatment with ZER(IC50=18µmol/L),compared to un-stimulated fibroblasts(IC50=40µmol/L).Besides,ZER inhibited mRNA expression and protein secretion of transforming growth factor-β(TGF-β),interleukin-33(IL-33),monocyte chemoattractant protein-1(MCP-1),and stromal cell-derived factor 1(SDF-1),which were produced by TNF-α-induced fibroblasts,as measured by quantitative real time-PCR(qRT-PCR)and ELISA assays.The mRNA expression levels of TGF-β,IL-33,SDF-1,and MCP-1 showed 8,5,2.5,and 4-fold reductions,respectively.Moreover,secretion of TGF-β,IL-33,SDF-1,and MCP-1 was reduced to 3.65±0.34 ng/mL,6.3±0.26,1703.6±295.2,and 5.02±0.18 pg/mL,respectively,compared to the untreated group.In addition,the conditioned media(CM)of TNF-α-stimulated fibroblasts increased the NF-κB expression in colorectal cancer cell lines(HCT-116 and Sw48),while in the vicinity of ZER,the expression of NF-κB was reversed.Considering the significant effects of ZER,this component can be used as an appropriate alternative herbal treatment for cancer-related chronic inflammation.展开更多
The relationship between intracelluar trypsinogen activation and NF-κB activation in rat pancreatic acinar cells induced by M3 cholinergic receptor agonist (carbachol) hyperstimulation was studied. Rat pancreatic a...The relationship between intracelluar trypsinogen activation and NF-κB activation in rat pancreatic acinar cells induced by M3 cholinergic receptor agonist (carbachol) hyperstimulation was studied. Rat pancreatic acinar cells were isolated, cultured and treated with carbachol, the active protease inhibitor (pefabloc) and NF-κB inhibitor (PDTC) in vitro. Intracelluar trypsin activity was measured by using a fluorogenic substrate. The activity of NF-κB was monitored by using electrophoretic mobility shift assay. The results showed that after pretreatment with 2 mmol/L pefabloc, the activities of trypsin and NF-κB in pancreatic acinar cells treated with high concertrations of carbachol (10^-3 mol/L) in vitro was significantly decreased as compared with control group (P〈0.01 ). The addition of 10^-2 mol/L PDTC resulted in a significant decrease of NF-κB activities in pancreatic acinar cells after treated with high concertrations of carbachol (10^-3 mol/L) in vitro, but the intracelluar trypsinogen activity was not obviously inhibited (P〉0.05). It was concluded that intracelluar trypsinogen activation is likely involved in the regulation of high concertrations of carbachol-induced NF-κB activation in pancreatic acinar cells in vitro. NF-κB activation is likely not necessary for high concertrations of carbachol-induced trypsinogen activation in pancreatic acinar cells in vitro.展开更多
The relationship between M3 cholinergic receptor agonist (carbachol) hyperstimulationinduced pancreatic acinar cellular injury and trypsinogen activation or NF-κB activation in rats was studied in vitro. Rat pancre...The relationship between M3 cholinergic receptor agonist (carbachol) hyperstimulationinduced pancreatic acinar cellular injury and trypsinogen activation or NF-κB activation in rats was studied in vitro. Rat pancreatic acinar ceils were isolated, cultured and treated with carbachol, the active protease inhibitor (pefabloc), and NF-κB inhibitor (PDTC) in vitro. Intracellular trypsin activity was measured by using a fluorogenic substrate. The cellular injury was evaluated by measuring the leakage of LDH from pancreatic acinar ceils. The results showed that as compared with control group, 10-3 mol/L carbachol induced a significant increase of the intracellular trypsin activity and the leakage of LDH from pancreatic acinar cells. Pretreatment with 2 mmol/L pefabloc could significantly decrease the activity of trypsin and the leakage of LDH from pancreatic acinar cells (P〈0. 01) following the treatment with a high concentration of carbachol (10^-3 mol/L) in vitro. The addition of 10^-2mol/L PDTC didn't result in a significant decrease in the activity of trypsin and the leakage of LDH from pancreatic acinar cells treated with a high concentration of carbachol (10^-3 mol/L) in vitro (P〉0. 05). It was concluded that intracellular trypsinogen activation is likely involved in pancreatic acinar cellular injury induced by carbachol hyperstimulation in vitro. NF-κB activation may not be involved in pancreatic acinar cellular injury induced by carbachol hyperstimulation in vitro.展开更多
Tetrandrine (1 μM), a bis-benzylisoquinoline alkaloid isolated from Stephania tetrandra S Moore, signifi-cantly decreased tumor necrosis factor alpha (TNFα;10 ng/ml)-induced increase in the number of micro vessels t...Tetrandrine (1 μM), a bis-benzylisoquinoline alkaloid isolated from Stephania tetrandra S Moore, signifi-cantly decreased tumor necrosis factor alpha (TNFα;10 ng/ml)-induced increase in the number of micro vessels that budded from cultured rat choroidal explants. Tetrandrine also decreased the TNFα-induced in-crease in the number of cells composing the microvessels. Ammonium pyrrolidine dithiocarbamate (APDC;0.1-0.3 μM), an inhibitor of nuclear factor-κB (NF-κB), decreased the TNFα-induced increase in the number of microvessels in a concentration-dependent manner. TNFα increased the phosphorylation and degradation of inhibitor of NF-κB (IκBα), as well as increasing the DNA-binding activity of NF-κB in choroidal explants. TNF? induced an increase of vascular endothelial growth factor (VEGF)-A mRNA, but not VEGF-C mRNA or VEGF-D mRNA. TNFα-induced angiogenic action was inhibited by treatment of VEGF-A antibody in cultured choroidal capillaries. Tetrandrine inhibited the TNFα-induced increases of phosphorylation and degradation of IκBα, and reduced the TNFα-induced increase of DNA-binding activity of NF-κB in chor-oidal explants. In conclusion, tetrandrine inhibits TNFα-induced activation of NF-κB in the choroidal capil-laries via inhibition of TNFα-induced phosphorylation of IκBα.展开更多
宫颈癌是女性第二好发的恶性肿瘤,对于晚期患者,放疗联合化疗是主要的治疗方法。但放化疗诱导的炎症使肿瘤产生了治疗抵抗并引起正常组织的损伤。其中激活的转录因子核因子-κB(nuclear factor-κB,NF-κB)和信号转导及转录激活因子3...宫颈癌是女性第二好发的恶性肿瘤,对于晚期患者,放疗联合化疗是主要的治疗方法。但放化疗诱导的炎症使肿瘤产生了治疗抵抗并引起正常组织的损伤。其中激活的转录因子核因子-κB(nuclear factor-κB,NF-κB)和信号转导及转录激活因子3(signal transducer and activator of transduction 3,STAT3),是炎症反应的中心环节。展开更多
Persistent generalized low bone mineral density (BMD) has been reported in patients with adolescent idiopathic scoliosis (AIS).However,the exact mechanisms and causes of the low BMD in AIS patients are largely unknown...Persistent generalized low bone mineral density (BMD) has been reported in patients with adolescent idiopathic scoliosis (AIS).However,the exact mechanisms and causes of the low BMD in AIS patients are largely unknown.The purpose of this study was to examine the relationship between the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) levels in osteoblasts (OBs) from AIS patients with low BMD and with comparison made between the patients and controls.Twenty AIS patients and eight age-matched controls were included in the present study.The BMD of lumbar spine and proximal femur was measured in all subjects.OBs from the cancellous bone of each subject was harvested and primarily cultured.The mRNA and protein expression of RANKL and OPG in OBs was detected by RT-PCR and Western blotting.The results showed BMD was lower in AIS patients than in controls.A significantly higher mRNA and protein expression of RANKL was observed in OBs from AIS patients,while no significant difference was found in the expression of OPG between AIS patients and controls.As a result,RANKL/OPG ratio in patients with AIS was remarkably higher than controls.Our study preliminarily demonstrated expression of RANKL was higher in OBs from AIS patients with low BMD as compared with controls,suggesting the unbalanced RANKL/OPG ratio caused by an over-expression of RANKL in OBs may be responsible for the low BMD in AIS patients.展开更多
Objective Antimony(Sb)has recently been identified as a novel nerve poison,although the cellular and molecular mechanisms underlying its neurotoxicity remain unclear.This study aimed to assess the effects of the nucle...Objective Antimony(Sb)has recently been identified as a novel nerve poison,although the cellular and molecular mechanisms underlying its neurotoxicity remain unclear.This study aimed to assess the effects of the nuclear factor kappa B(NF-κB)signaling pathway on antimony-induced astrocyte activation.Methods Protein expression levels were detected by Western blotting.Immunofluorescence,cytoplasmic and nuclear fractions separation were used to assess the distribution of p65.The expression of protein in brain tissue sections was detected by immunohistochemistry.The levels of mRNAs were detected by Quantitative real-time polymerase chain reaction(qRT-PCR)and reverse transcriptionpolymerase chain reaction(RT-PCR).Results Antimony exposure triggered astrocyte proliferation and increased the expression of two critical protein markers of reactive astrogliosis,inducible nitric oxide synthase(iNOS)and glial fibrillary acidic protein(GFAP),indicating that antimony induced astrocyte activation in vivo and in vitro.Antimony exposure consistently upregulated the expression of inflammatory factors.Moreover,it induced the NF-κB signaling,indicated by increased p65 phosphorylation and translocation to the nucleus.NF-κB inhibition effectively attenuated antimony-induced astrocyte activation.Furthermore,antimony phosphorylated TGF-β-activated kinase 1(TAK1),while TAK1 inhibition alleviated antimonyinduced p65 phosphorylation and subsequent astrocyte activation.Conclusion Antimony activated astrocytes by activating the NF-κB signaling pathway.展开更多
Osteoclasts are the bone resorbing cells essential for bone remodeling.Osteoclasts are formed from hematopoietic progenitors in the monocyte/macrophage lineage.Osteoclastogenesis is composed of several steps including...Osteoclasts are the bone resorbing cells essential for bone remodeling.Osteoclasts are formed from hematopoietic progenitors in the monocyte/macrophage lineage.Osteoclastogenesis is composed of several steps including progenitor survival,differentiation to mononuclear pre-osteoclasts,fusion to multi-nuclear mature osteoclasts,and activation to bone resorbing osteoclasts.The regulation of osteoclastogenesis has been extensively studied,in which the receptor activator of NF-κB ligand(RANKL)-mediated signaling pathway and downstream transcription factors play essential roles.However,less is known about osteoclast fusion,which is a property of mature osteoclasts and is required for osteoclasts to resorb bone.Several proteins that affect cell fusion have been identified.Among them,dritic cell-specific transmembrane protein(DC-STAMP)is directly associated to osteoclast fusion in vivo.Cytokines and factors influence osteoclast fusion through regula-tion of DC-STAMP.Here we review the recently discovered new factors that regulate osteoclast fusion with specific focus on DC-STAMP.A better understanding of the mechanistic basis of osteoclast fusion will lead to the development of a new therapeutic strategy for bone disorders due to elevated osteoclast bone resorption.Cell-cell fusion is essential for a variety of cellular biological processes.In mammals,there is a limited number of cell types that fuse to form multinucleated cells,such as the fusion of myoblasts for the formation of skeletal muscle and the fusion of cells of the monocyte/macrophage lineage for the formation of multinucleated osteoclasts and giant cells.In most cases,cellcell fusion is beneficial for cells by enhancing function.Myoblast fusion increases myofiber size and diameter and thereby increases contractile strength.Multinucleated osteoclasts have far more bone resorbing activity than their mono-nuclear counterparts.Multinucleated giant cells are much more efficient in the removal of implanted materials and bacteria due to chronic infection than macrophages.Therefore,they are also called foreign-body giant cells.Cell fusion is a complicated process involving cell migration,chemotaxis,cell-cell recognition and attachment,as well as changes into a fusion-competent status.All of these steps are regulated by multiple factors.In this review,we will discuss osteoclast fusion and regulation.展开更多
Objective:To investigate the immunomodulatory activity of polysaccharides from the roots of Brassica rapa.Methods:The crude polysaccharide from roots of B.rapa(BRP)was extracted and purified to further investigate the...Objective:To investigate the immunomodulatory activity of polysaccharides from the roots of Brassica rapa.Methods:The crude polysaccharide from roots of B.rapa(BRP)was extracted and purified to further investigate the active fraction of BRT for inducing macrophage phagocytosis.Results:Effects on RAW264.7 cells demonstrated that BRP behaved better phagocytic capacity and had potent immunomodulatory activity,including increasing production of nitric oxide(NO),tumor necrosis factor a(TNFa)and upregulating mRNA levels of inducible NO synthase(iNOS)and TNFa.Furthermore,modulation of macrophage by BRP was indicated to be mediated via the activation of Akt and nuclear factor-kappa B(NF-κB).Conclusion:The beneficial effects of BRP could be used as an immunotherapeutic adjuvant in treatment of inflammatory diseases.展开更多
Objective: To investigate the curative efficacy of vitamin D3 in combination with tripterygium wilfordii polyglycoside in patients with rheumatoid arthritis (RA) and its influences on indices of bone restoration. Meth...Objective: To investigate the curative efficacy of vitamin D3 in combination with tripterygium wilfordii polyglycoside in patients with rheumatoid arthritis (RA) and its influences on indices of bone restoration. Methods: A total of 320 patients with RA were collected as observation objects to be randomly divided into the control group and the observation group with 160 cases in each group. The control group was given treatment of tripterygium wilfordii polyglycoside, while the observation group was given treatment of vitamin D3 in combination with tripterygium wilfordii polyglycoside. All patients received a course treatment with 3 months. The curative efficacy, improvement of joint symptoms, changes of laboratory tests, indices of bone restoration and adverse reactions were compared. Results: After 3 months, assessment of curative efficacy showed that the observation group had a total curative efficiency ratio of 90.6%, which was significantly higher than that of 81.2% in the control group. Among the indices which reflect the improvement of joint symptoms, the joint pain index, joint tenderness index and joint swollenness index were statistically reduced in the observation group than those in the control group. And after treatment, in comparison with the control group, indices of laboratory tests of rheumatoid factor (RF), antistreptolyisn O antibody (ASO), c-reactive protein (CRP) were statistically lower respectively in the observation group. As to indices of bone restoration after treatment, the observation group had statistically lower serum level of receptor activator of nf-kb ligand (RNKL) and higher level of osteoprotegerin (OPG) than those in the control group. During the treatment, incidences of adverse reactions in the control group and the observation group were statistically same. Conclusion: Vitamin D3 in combination with tripterygium wilfordii polyglycoside has well curative efficacy in patients with RA, which can significantly improve joint symptoms, indices of laboratory tests and bone restoration.展开更多
Background: Members of the NFκB [p65] family have potential diagnostic and prognostic role in various inflammatory diseases and Lymphomas. Aim: We studied NFκB [p65] in paraffin blocks of hepatitis-C-virus [HCV] pos...Background: Members of the NFκB [p65] family have potential diagnostic and prognostic role in various inflammatory diseases and Lymphomas. Aim: We studied NFκB [p65] in paraffin blocks of hepatitis-C-virus [HCV] positive genotype-4 and HCV negative diffuse large B-cell lymphoma [DLBCL] patients, aiming at identification of its differential expression and prognosis in DLBCL and its subtypes;GCB and ABC. This is to establish its relation to HCV infection and its role in lymphogenesis. Besides assessing the role of new directly acting antiviral drugs [Sofusbuvir/Ledipasvir] concomitantly administered to [CHOP] combination in HCV positive DLBCL. Subjects and Methods: NFκB [p65] expression was assessed using Anti-NFκB [p65] antibody semi-quantitative technique in 30 newly diagnosed DLBCL patients [HCV positive [n = 15], HCV negative [n = 15]. Results: NFκB [p65] expression was higher in the HCV positive DLBCL patients than their HCV negative counterpart, with a positive correlation with the viral load [r = 0.536, p = 0.088]. NFκB [p65] expression was significantly more frequently detected in the ABC subtype than GCB subtype [p = 0.04]. Patients who expressed NFκB [p65] had higher incidence of extranodal involvement, advanced stages, higher LDH levels and IPI score. Besides, the expression of NFκB [P65] revealed an inferior overall response [OR] [p = 0.044]. Higher complete response rates to CHOP concomitantly with antiviral [ledipasvir/sofosbuvir] were encountered in the HCV positive group. In HCV positive group, NFκB [P65] displayed a positive relationship with the viral load and liver enzymes [p = 0.04], besides an inverse relation with serum albumin. This raises the possibility that NFκB [p65] expression is suggestive of the hepatic necro-inflammation in HCV patients. The ABC group presented more in advanced stages than GCB. Higher frequency of the ABC subgroup exhibited intermediate to high viral load, while it was less in the GCB. A statistically significant difference was found in the NFκB [p65] positive patients as regards MUM1 expression among the two groups [p ≤ 0.001]. Double positive [CD10+, MUM1+] and triple negative [CD10-, BCL6-, MUM1-] cases were encountered in the HCV positive group, and were characterized with a high NFκB [p65] expression. Conclusion: NFκB [p65] is expressed in patients with DLBCL, more frequently in ABC than in GCB subtypes. Expression of NFκB [p65] is associated with poor response to therapy in DLBCL. The NFκB [p65] disclosed an increased expression in HCV positive DLBCL compared to HCV negative group. The viral load displayed a positive correlation with the NFκB [p65] expression. Simultaneous administration of DAAs in combination with CHOP disclosed a better response and high tolerability.展开更多
Objective:To study the correlation of OPG/RANKL expression in gingival crevicular fluid with inflammatory factors, free radical generation and bone metabolism in patients with diabetes mellitus complicated by periodon...Objective:To study the correlation of OPG/RANKL expression in gingival crevicular fluid with inflammatory factors, free radical generation and bone metabolism in patients with diabetes mellitus complicated by periodontitis.Methods:Patients with diabetes mellitus complicated by periodontitis who were treated in Xi'an No. 4 Hospital between March 2015 and May 2017 were selected as the periodontitis group for the research, and healthy volunteers who underwent periodontal examination during the same period were selected as the control group. The gingival crevicular fluid was collected to determine the expression of OPG/RANKL, the contents of inflammatory factors and bone metabolism molecules as well as the generation of free radicals.Results: OPG protein expression, OPG/RANKL expression ratio as well as ICTP and Runx2 contents in gingival crevicular fluid of periodontitis group were significantly lower than those of control group whereas RANKL protein expression, TNF-α, IL-1β, IL-17, HMGB1, DKK1 and MMP1 contents as well as ROS, MDA and 8-OHdG generation were significantly higher than those of control group;OPG/RANKL expression ratio in gingival crevicular fluid of periodontitis group was negatively correlated with TNF- , IL-1β, IL-17, HMGB1, DKK1 and MMP1 contents as well as ROS, MDA and 8-OHdG generation, and positively correlated with ICTP and Runx2 contents.Conclusion: The excessive activation of inflammation and oxidative stress in periodontal tissue of patients with diabetes mellitus complicated by periodontitis can cause OPG/RANKL expression disorder and then lead to bone metabolism disorder.展开更多
Endothelial activation by proinflammatory cytokines is closely associated to the pathogenesis of atherosclerosis and other vascular diseases;however, the molecular mechanisms controlling endothelial activation are not...Endothelial activation by proinflammatory cytokines is closely associated to the pathogenesis of atherosclerosis and other vascular diseases;however, the molecular mechanisms controlling endothelial activation are not fully understood. Here we identify TRIM14 as a new positive regulator of endothelial activation via activating NF-κB signal pathway. TRIM14 is highly expressed in human vascular endothelial cells (ECs) and markedly induced by inflammatory stimuli such as TNF-α, IL-1β, and LPS. Overexpression of TRIM14 significantly increased the expression of adhesion molecules such as VCAM-1, ICAM-1, E-selectin, and cytokines such as CCL2, IL-8, CXCL-1, and TNF-α in activated ECs and by which it facilitated monocyte adhesion to ECs. Conversely, knockdown of TRIM14 has opposite effect on endothelial activation. Upon TNF-α stimulation, TRIM14 is recruited to IKK complex via directly binding to NEMO and promotes the phosphorylation of IκBα and p65, which is dependent on its K63-linked ubiquitination. Meanwhile, p65 can directly bind to the promoter regions of human TRIM14 gene and control its mRNA transcription. Finally, TRIM14 protein level is significantly upregulated in mouse and human atheroma compared to normal arteries. Taken together, these results indicate that TRIM14-NF-κB forms a positive feedback loop to enhance EC activation and TRIM14 may be a potential therapeutic target for vascular inflammatory diseases such as atherosclerosis.展开更多
Background:Gram-positive bacteria stimulate Toll-like receptor(TLR)2 and then activate the pro-inflammatory nuclear factor-kappa B(NF-κB)pathway.As the human ocular surface is heavily colonised by gram-positive cocci...Background:Gram-positive bacteria stimulate Toll-like receptor(TLR)2 and then activate the pro-inflammatory nuclear factor-kappa B(NF-κB)pathway.As the human ocular surface is heavily colonised by gram-positive cocci bacteria,a balance of activation/repression of NF-κB target genes is essential to avoid uncontrolled infection or autoimmune-related inflammation.It is advantageous to test NF-κB targeting molecules in an ocular surface culture system that allows assessment of temporal NF-κB activation in a longitudinal fashion without destruction of cells.Such initial testing under standardised conditions should reduce the number of molecules that progress to further evaluation in animal models.This study aims to establish an in-vitro cell culture system to assess NF-κB activation in the context of ocular surface cells.Methods:NF-κB activity was evaluated through a secretory alkaline phosphatase reporter assay(SEAP).Immunoblots and immunofluorescence were used to examine IκBαphosphorylation and p65/p50 nuclear localization.Monocyte chemoattractant protein-1(MCP-1)transcripts were evaluated by real time PCR and protein levels were measured by ELISA.Results:NF-κB activity in HCE-T cells treated with TLR2 activator Pam3CSK4 was higher than control cells at both 6 and 24 h.Pam3CSK4-stimulated NF-κB activation was inhibited by IκK inhibitors,Wedelolactone and BMS-345541.In Pam3CSK4 treated cells,active NF-κB subunits p50 and p65 increased in cell nuclear fractions as early as 1.5 h.Although the level of total IκB-αremained constant,phospho-IκB-αincreased with treatment over time.In the culture media of Pam3CSK4-stimulated cells,MCP-1 protein level was increased,which was suppressed in the presence of IκK inhibitors.Conclusion:NF-κB pathway can be activated by the TLR2 ligand and inhibited by IκK inhibitors in the ocular surface cell culture system.This cell culture system may be used to evaluate TLR-related innate defences in ocular surface diseases.展开更多
Dear Editor,Chemotherapy is one of major means for cancer treatments, and many of chemotherapeutic drugs are DNA damaging agents that reduce tumor growth through triggering cancer cell apoptosis or necrosis. Following...Dear Editor,Chemotherapy is one of major means for cancer treatments, and many of chemotherapeutic drugs are DNA damaging agents that reduce tumor growth through triggering cancer cell apoptosis or necrosis. Following DNA damage, ataxia telangiectasia mutated (ATM), a protein kinase, was acti- vated and a cytosolic complex containing ATM, NEMO, RIP1 were formed (Biton and Ashkenazi, 2011).展开更多
The paracaspase MALT1 is essential for the activation of NF-κB in response to T cell receptor(TCR)stimula-tion.It recruits downstream TRAF6 and activates the E3 ligase activity of TRAF6 to polyubiquitinate several ta...The paracaspase MALT1 is essential for the activation of NF-κB in response to T cell receptor(TCR)stimula-tion.It recruits downstream TRAF6 and activates the E3 ligase activity of TRAF6 to polyubiquitinate several targets,which ultimately leads to NF-κB activation.Here we identified ubiquitin-specific protease 2a(USP2a)as a MALT1-associated protein by biochemical affinity purification.Endogenous USP2a constitutively interacted with TRAF6,but dynamically interacted with MALT1 and CARMA1 in a stimulation-dependent man-ner.RNA interference(RNAi)-mediated silencing of USP2a attenuated TCR-induced NF-κB activation and production of interleukin-2(IL-2).In addition,the ubiq-uitination of MALT1 and TRAF6 were both suppressed by USP2a knockdown.By knockdown and reconstitu-tion assays,we found that USP2a mediated the interac-tion between MALT1 and TRAF6 in a catalytic activ-ity-dependent manner.Furthermore,USP2a deSUMOy-lated TRAF6.Our findings implicate that USP2a plays an important role in TCR signaling by deSUMOylating TRAF6 and mediating TRAF6-MALT1 interaction.展开更多
NF-κB signaling controls a large set of physiological processes ranging from inflammatory responses to cell death. Its activation is tightly regulated through controlling the activity and stability of multiple signal...NF-κB signaling controls a large set of physiological processes ranging from inflammatory responses to cell death. Its activation is tightly regulated through controlling the activity and stability of multiple signaling components. Here, we identify that NF-κB activation is suppressed by an F-box protein, S-phase kinase associated protein 2 (SKP2). SKP2 deficiency enhanced NF-κB activation as well as the production of inflammatory cytokines. In addition, SKP2 potently blocked the NF-κB activation at the κB kinase (IKIO level. Mechanistic study further revealed that SKP2 functions as an adaptor to promote an interaction between active IKKβ and the autophagic cargo receptor p62 to mediate IKKβ degradation via selective autophasy. These findings identify a previously unrecognized role of SKP2 in NF-κB activation by which SKP2 acts as a secondary receptor to assist IKKβ delivery to autophagosomes for degradation in a p62-dependent manner.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(81973316,82173807)the China Postdoctoral Science Foundation(2020M681914)+1 种基金the Fund from Tianjin Municipal Health Commission(ZC200093)the Open Fund of Tianjin Central Hospital of Obstetrics and Gynecology/Tianjin Key Laboratory of human development and reproductive regulation(2021XHY01)。
文摘Psoriasis is a chronic autoimmune disease featured by patches on the skin.It is caused by malfunction of immune cells and keratinocytes with inflammation as one of its key features.Apigenin(API)is a natural flavonoid with anti-inflammatory and immunoregulatory properties.Therefore,we speculated that API can ameliorate psoriasis,and determined its effect on the development of psoriasis by using imiquimod(IMQ)-induced psoriasis mouse model.Our results showed that API attenuated IMQ-induced phenotypic changes,such as erythema,scaling and epidermal thickening,and improved splenic hyperplasia.Abnormal differentiation of immune cells was restored in API-treated mice.Mechanistically,we revealed that API is a key regulator of signal transducer activator of transcription 3(STAT3).API regulated immune responses by reducing interleukin-23(IL-23)/STAT3/IL-17A axis.Moreover,it suppressed IMQ-caused cell hyperproliferation by inactivating STAT3 through regulation of extracellular signal-regulated kinase 1/2 and nuclear factor-κB(NF-κB)pathway.Furthermore,API reduced expression of inflammatory cytokines through inactivation of NF-κB.Taken together,our study demonstrates that API can ameliorate psoriasis and may be considered as a strategy for psoriasis treatment.
基金This study was supported by a grant from Hamadan University of Medical Sciences(No.9511267103).
文摘Inflammation plays an important role in the development of several cancers.Inflammatory cytokines,including tumor necrosis factor-α(TNF-α),are associated with the induction of inflammation.Chronic inflammation contributes to the progression of cancer through several mechanisms,including increased cytokine production and activation of transcription factors,such as nuclear factor-κB(NF-κB).Zerumbone(ZER),a component of subtropical ginger(Zingiber zerumbet Smith),seems to have anti-inflammatory,anti-cancer,and antioxidant activities.In this study,we aimed to explore the protective function and mechanisms of ZER against TNF-α-induced cancer-promoting cytokines.We found that the viability of stimulated human fibroblast cell lines was reduced after treatment with ZER(IC50=18µmol/L),compared to un-stimulated fibroblasts(IC50=40µmol/L).Besides,ZER inhibited mRNA expression and protein secretion of transforming growth factor-β(TGF-β),interleukin-33(IL-33),monocyte chemoattractant protein-1(MCP-1),and stromal cell-derived factor 1(SDF-1),which were produced by TNF-α-induced fibroblasts,as measured by quantitative real time-PCR(qRT-PCR)and ELISA assays.The mRNA expression levels of TGF-β,IL-33,SDF-1,and MCP-1 showed 8,5,2.5,and 4-fold reductions,respectively.Moreover,secretion of TGF-β,IL-33,SDF-1,and MCP-1 was reduced to 3.65±0.34 ng/mL,6.3±0.26,1703.6±295.2,and 5.02±0.18 pg/mL,respectively,compared to the untreated group.In addition,the conditioned media(CM)of TNF-α-stimulated fibroblasts increased the NF-κB expression in colorectal cancer cell lines(HCT-116 and Sw48),while in the vicinity of ZER,the expression of NF-κB was reversed.Considering the significant effects of ZER,this component can be used as an appropriate alternative herbal treatment for cancer-related chronic inflammation.
文摘The relationship between intracelluar trypsinogen activation and NF-κB activation in rat pancreatic acinar cells induced by M3 cholinergic receptor agonist (carbachol) hyperstimulation was studied. Rat pancreatic acinar cells were isolated, cultured and treated with carbachol, the active protease inhibitor (pefabloc) and NF-κB inhibitor (PDTC) in vitro. Intracelluar trypsin activity was measured by using a fluorogenic substrate. The activity of NF-κB was monitored by using electrophoretic mobility shift assay. The results showed that after pretreatment with 2 mmol/L pefabloc, the activities of trypsin and NF-κB in pancreatic acinar cells treated with high concertrations of carbachol (10^-3 mol/L) in vitro was significantly decreased as compared with control group (P〈0.01 ). The addition of 10^-2 mol/L PDTC resulted in a significant decrease of NF-κB activities in pancreatic acinar cells after treated with high concertrations of carbachol (10^-3 mol/L) in vitro, but the intracelluar trypsinogen activity was not obviously inhibited (P〉0.05). It was concluded that intracelluar trypsinogen activation is likely involved in the regulation of high concertrations of carbachol-induced NF-κB activation in pancreatic acinar cells in vitro. NF-κB activation is likely not necessary for high concertrations of carbachol-induced trypsinogen activation in pancreatic acinar cells in vitro.
文摘The relationship between M3 cholinergic receptor agonist (carbachol) hyperstimulationinduced pancreatic acinar cellular injury and trypsinogen activation or NF-κB activation in rats was studied in vitro. Rat pancreatic acinar ceils were isolated, cultured and treated with carbachol, the active protease inhibitor (pefabloc), and NF-κB inhibitor (PDTC) in vitro. Intracellular trypsin activity was measured by using a fluorogenic substrate. The cellular injury was evaluated by measuring the leakage of LDH from pancreatic acinar ceils. The results showed that as compared with control group, 10-3 mol/L carbachol induced a significant increase of the intracellular trypsin activity and the leakage of LDH from pancreatic acinar cells. Pretreatment with 2 mmol/L pefabloc could significantly decrease the activity of trypsin and the leakage of LDH from pancreatic acinar cells (P〈0. 01) following the treatment with a high concentration of carbachol (10^-3 mol/L) in vitro. The addition of 10^-2mol/L PDTC didn't result in a significant decrease in the activity of trypsin and the leakage of LDH from pancreatic acinar cells treated with a high concentration of carbachol (10^-3 mol/L) in vitro (P〉0. 05). It was concluded that intracellular trypsinogen activation is likely involved in pancreatic acinar cellular injury induced by carbachol hyperstimulation in vitro. NF-κB activation may not be involved in pancreatic acinar cellular injury induced by carbachol hyperstimulation in vitro.
文摘Tetrandrine (1 μM), a bis-benzylisoquinoline alkaloid isolated from Stephania tetrandra S Moore, signifi-cantly decreased tumor necrosis factor alpha (TNFα;10 ng/ml)-induced increase in the number of micro vessels that budded from cultured rat choroidal explants. Tetrandrine also decreased the TNFα-induced in-crease in the number of cells composing the microvessels. Ammonium pyrrolidine dithiocarbamate (APDC;0.1-0.3 μM), an inhibitor of nuclear factor-κB (NF-κB), decreased the TNFα-induced increase in the number of microvessels in a concentration-dependent manner. TNFα increased the phosphorylation and degradation of inhibitor of NF-κB (IκBα), as well as increasing the DNA-binding activity of NF-κB in choroidal explants. TNF? induced an increase of vascular endothelial growth factor (VEGF)-A mRNA, but not VEGF-C mRNA or VEGF-D mRNA. TNFα-induced angiogenic action was inhibited by treatment of VEGF-A antibody in cultured choroidal capillaries. Tetrandrine inhibited the TNFα-induced increases of phosphorylation and degradation of IκBα, and reduced the TNFα-induced increase of DNA-binding activity of NF-κB in chor-oidal explants. In conclusion, tetrandrine inhibits TNFα-induced activation of NF-κB in the choroidal capil-laries via inhibition of TNFα-induced phosphorylation of IκBα.
文摘宫颈癌是女性第二好发的恶性肿瘤,对于晚期患者,放疗联合化疗是主要的治疗方法。但放化疗诱导的炎症使肿瘤产生了治疗抵抗并引起正常组织的损伤。其中激活的转录因子核因子-κB(nuclear factor-κB,NF-κB)和信号转导及转录激活因子3(signal transducer and activator of transduction 3,STAT3),是炎症反应的中心环节。
基金supported by the National Natural ScienceFoundation of China (No.81101335)
文摘Persistent generalized low bone mineral density (BMD) has been reported in patients with adolescent idiopathic scoliosis (AIS).However,the exact mechanisms and causes of the low BMD in AIS patients are largely unknown.The purpose of this study was to examine the relationship between the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) levels in osteoblasts (OBs) from AIS patients with low BMD and with comparison made between the patients and controls.Twenty AIS patients and eight age-matched controls were included in the present study.The BMD of lumbar spine and proximal femur was measured in all subjects.OBs from the cancellous bone of each subject was harvested and primarily cultured.The mRNA and protein expression of RANKL and OPG in OBs was detected by RT-PCR and Western blotting.The results showed BMD was lower in AIS patients than in controls.A significantly higher mRNA and protein expression of RANKL was observed in OBs from AIS patients,while no significant difference was found in the expression of OPG between AIS patients and controls.As a result,RANKL/OPG ratio in patients with AIS was remarkably higher than controls.Our study preliminarily demonstrated expression of RANKL was higher in OBs from AIS patients with low BMD as compared with controls,suggesting the unbalanced RANKL/OPG ratio caused by an over-expression of RANKL in OBs may be responsible for the low BMD in AIS patients.
基金supported by the National Natural Science Foundation of China[21477058,81703255]Scientific Research Project of Nantong of Jiangsu[JC2019027,JC2019137]+2 种基金the Qing Lan Project for Excellent Young Key Teachers of Colleges and Universities of Jiangsu Province(2020)the Postgraduate Research&Practice Innovation Program of Jiangsu Province[KYCX20_2854]Large Instruments Open Foundation of Nantong University[KFJN2054]。
文摘Objective Antimony(Sb)has recently been identified as a novel nerve poison,although the cellular and molecular mechanisms underlying its neurotoxicity remain unclear.This study aimed to assess the effects of the nuclear factor kappa B(NF-κB)signaling pathway on antimony-induced astrocyte activation.Methods Protein expression levels were detected by Western blotting.Immunofluorescence,cytoplasmic and nuclear fractions separation were used to assess the distribution of p65.The expression of protein in brain tissue sections was detected by immunohistochemistry.The levels of mRNAs were detected by Quantitative real-time polymerase chain reaction(qRT-PCR)and reverse transcriptionpolymerase chain reaction(RT-PCR).Results Antimony exposure triggered astrocyte proliferation and increased the expression of two critical protein markers of reactive astrogliosis,inducible nitric oxide synthase(iNOS)and glial fibrillary acidic protein(GFAP),indicating that antimony induced astrocyte activation in vivo and in vitro.Antimony exposure consistently upregulated the expression of inflammatory factors.Moreover,it induced the NF-κB signaling,indicated by increased p65 phosphorylation and translocation to the nucleus.NF-κB inhibition effectively attenuated antimony-induced astrocyte activation.Furthermore,antimony phosphorylated TGF-β-activated kinase 1(TAK1),while TAK1 inhibition alleviated antimonyinduced p65 phosphorylation and subsequent astrocyte activation.Conclusion Antimony activated astrocytes by activating the NF-κB signaling pathway.
基金Supported by(in part)Grants R01-AR43510 to Boyce BF and R01-AR48697 to Xing L from the National Institute of Arthritis and Musculoskeletal and Skin Diseases,United States
文摘Osteoclasts are the bone resorbing cells essential for bone remodeling.Osteoclasts are formed from hematopoietic progenitors in the monocyte/macrophage lineage.Osteoclastogenesis is composed of several steps including progenitor survival,differentiation to mononuclear pre-osteoclasts,fusion to multi-nuclear mature osteoclasts,and activation to bone resorbing osteoclasts.The regulation of osteoclastogenesis has been extensively studied,in which the receptor activator of NF-κB ligand(RANKL)-mediated signaling pathway and downstream transcription factors play essential roles.However,less is known about osteoclast fusion,which is a property of mature osteoclasts and is required for osteoclasts to resorb bone.Several proteins that affect cell fusion have been identified.Among them,dritic cell-specific transmembrane protein(DC-STAMP)is directly associated to osteoclast fusion in vivo.Cytokines and factors influence osteoclast fusion through regula-tion of DC-STAMP.Here we review the recently discovered new factors that regulate osteoclast fusion with specific focus on DC-STAMP.A better understanding of the mechanistic basis of osteoclast fusion will lead to the development of a new therapeutic strategy for bone disorders due to elevated osteoclast bone resorption.Cell-cell fusion is essential for a variety of cellular biological processes.In mammals,there is a limited number of cell types that fuse to form multinucleated cells,such as the fusion of myoblasts for the formation of skeletal muscle and the fusion of cells of the monocyte/macrophage lineage for the formation of multinucleated osteoclasts and giant cells.In most cases,cellcell fusion is beneficial for cells by enhancing function.Myoblast fusion increases myofiber size and diameter and thereby increases contractile strength.Multinucleated osteoclasts have far more bone resorbing activity than their mono-nuclear counterparts.Multinucleated giant cells are much more efficient in the removal of implanted materials and bacteria due to chronic infection than macrophages.Therefore,they are also called foreign-body giant cells.Cell fusion is a complicated process involving cell migration,chemotaxis,cell-cell recognition and attachment,as well as changes into a fusion-competent status.All of these steps are regulated by multiple factors.In this review,we will discuss osteoclast fusion and regulation.
基金supported by grants from the Natural Science Foundation of China (81760778)the Fundamental Research Funds for Public-interest Scientific Institution in Xinjiang Uygur Autonomous Region (KYGY2016169)CAMS Innovation Fund for Medical Sciences (2017-I2M-1-012)
文摘Objective:To investigate the immunomodulatory activity of polysaccharides from the roots of Brassica rapa.Methods:The crude polysaccharide from roots of B.rapa(BRP)was extracted and purified to further investigate the active fraction of BRT for inducing macrophage phagocytosis.Results:Effects on RAW264.7 cells demonstrated that BRP behaved better phagocytic capacity and had potent immunomodulatory activity,including increasing production of nitric oxide(NO),tumor necrosis factor a(TNFa)and upregulating mRNA levels of inducible NO synthase(iNOS)and TNFa.Furthermore,modulation of macrophage by BRP was indicated to be mediated via the activation of Akt and nuclear factor-kappa B(NF-κB).Conclusion:The beneficial effects of BRP could be used as an immunotherapeutic adjuvant in treatment of inflammatory diseases.
基金National Natural Science Foundation of China(81301532)Shanxi Returned Overseas Students'Scientific Research Foundation Project(2017-119)+1 种基金Shanxi Key Research and Development Program(Guidelines)Project(201603D321074)Shanxi Overseas Students'Scientific and Technological Activities Selective Foundation Project in 2017.
文摘Objective: To investigate the curative efficacy of vitamin D3 in combination with tripterygium wilfordii polyglycoside in patients with rheumatoid arthritis (RA) and its influences on indices of bone restoration. Methods: A total of 320 patients with RA were collected as observation objects to be randomly divided into the control group and the observation group with 160 cases in each group. The control group was given treatment of tripterygium wilfordii polyglycoside, while the observation group was given treatment of vitamin D3 in combination with tripterygium wilfordii polyglycoside. All patients received a course treatment with 3 months. The curative efficacy, improvement of joint symptoms, changes of laboratory tests, indices of bone restoration and adverse reactions were compared. Results: After 3 months, assessment of curative efficacy showed that the observation group had a total curative efficiency ratio of 90.6%, which was significantly higher than that of 81.2% in the control group. Among the indices which reflect the improvement of joint symptoms, the joint pain index, joint tenderness index and joint swollenness index were statistically reduced in the observation group than those in the control group. And after treatment, in comparison with the control group, indices of laboratory tests of rheumatoid factor (RF), antistreptolyisn O antibody (ASO), c-reactive protein (CRP) were statistically lower respectively in the observation group. As to indices of bone restoration after treatment, the observation group had statistically lower serum level of receptor activator of nf-kb ligand (RNKL) and higher level of osteoprotegerin (OPG) than those in the control group. During the treatment, incidences of adverse reactions in the control group and the observation group were statistically same. Conclusion: Vitamin D3 in combination with tripterygium wilfordii polyglycoside has well curative efficacy in patients with RA, which can significantly improve joint symptoms, indices of laboratory tests and bone restoration.
文摘Background: Members of the NFκB [p65] family have potential diagnostic and prognostic role in various inflammatory diseases and Lymphomas. Aim: We studied NFκB [p65] in paraffin blocks of hepatitis-C-virus [HCV] positive genotype-4 and HCV negative diffuse large B-cell lymphoma [DLBCL] patients, aiming at identification of its differential expression and prognosis in DLBCL and its subtypes;GCB and ABC. This is to establish its relation to HCV infection and its role in lymphogenesis. Besides assessing the role of new directly acting antiviral drugs [Sofusbuvir/Ledipasvir] concomitantly administered to [CHOP] combination in HCV positive DLBCL. Subjects and Methods: NFκB [p65] expression was assessed using Anti-NFκB [p65] antibody semi-quantitative technique in 30 newly diagnosed DLBCL patients [HCV positive [n = 15], HCV negative [n = 15]. Results: NFκB [p65] expression was higher in the HCV positive DLBCL patients than their HCV negative counterpart, with a positive correlation with the viral load [r = 0.536, p = 0.088]. NFκB [p65] expression was significantly more frequently detected in the ABC subtype than GCB subtype [p = 0.04]. Patients who expressed NFκB [p65] had higher incidence of extranodal involvement, advanced stages, higher LDH levels and IPI score. Besides, the expression of NFκB [P65] revealed an inferior overall response [OR] [p = 0.044]. Higher complete response rates to CHOP concomitantly with antiviral [ledipasvir/sofosbuvir] were encountered in the HCV positive group. In HCV positive group, NFκB [P65] displayed a positive relationship with the viral load and liver enzymes [p = 0.04], besides an inverse relation with serum albumin. This raises the possibility that NFκB [p65] expression is suggestive of the hepatic necro-inflammation in HCV patients. The ABC group presented more in advanced stages than GCB. Higher frequency of the ABC subgroup exhibited intermediate to high viral load, while it was less in the GCB. A statistically significant difference was found in the NFκB [p65] positive patients as regards MUM1 expression among the two groups [p ≤ 0.001]. Double positive [CD10+, MUM1+] and triple negative [CD10-, BCL6-, MUM1-] cases were encountered in the HCV positive group, and were characterized with a high NFκB [p65] expression. Conclusion: NFκB [p65] is expressed in patients with DLBCL, more frequently in ABC than in GCB subtypes. Expression of NFκB [p65] is associated with poor response to therapy in DLBCL. The NFκB [p65] disclosed an increased expression in HCV positive DLBCL compared to HCV negative group. The viral load displayed a positive correlation with the NFκB [p65] expression. Simultaneous administration of DAAs in combination with CHOP disclosed a better response and high tolerability.
文摘Objective:To study the correlation of OPG/RANKL expression in gingival crevicular fluid with inflammatory factors, free radical generation and bone metabolism in patients with diabetes mellitus complicated by periodontitis.Methods:Patients with diabetes mellitus complicated by periodontitis who were treated in Xi'an No. 4 Hospital between March 2015 and May 2017 were selected as the periodontitis group for the research, and healthy volunteers who underwent periodontal examination during the same period were selected as the control group. The gingival crevicular fluid was collected to determine the expression of OPG/RANKL, the contents of inflammatory factors and bone metabolism molecules as well as the generation of free radicals.Results: OPG protein expression, OPG/RANKL expression ratio as well as ICTP and Runx2 contents in gingival crevicular fluid of periodontitis group were significantly lower than those of control group whereas RANKL protein expression, TNF-α, IL-1β, IL-17, HMGB1, DKK1 and MMP1 contents as well as ROS, MDA and 8-OHdG generation were significantly higher than those of control group;OPG/RANKL expression ratio in gingival crevicular fluid of periodontitis group was negatively correlated with TNF- , IL-1β, IL-17, HMGB1, DKK1 and MMP1 contents as well as ROS, MDA and 8-OHdG generation, and positively correlated with ICTP and Runx2 contents.Conclusion: The excessive activation of inflammation and oxidative stress in periodontal tissue of patients with diabetes mellitus complicated by periodontitis can cause OPG/RANKL expression disorder and then lead to bone metabolism disorder.
基金supported by The National Natural Science Foundation of China(81660390,31760329,and 81301964)M.F.was supported by American Heart Association(17AIREA33660073)and NIH Grant(AI103618)。
文摘Endothelial activation by proinflammatory cytokines is closely associated to the pathogenesis of atherosclerosis and other vascular diseases;however, the molecular mechanisms controlling endothelial activation are not fully understood. Here we identify TRIM14 as a new positive regulator of endothelial activation via activating NF-κB signal pathway. TRIM14 is highly expressed in human vascular endothelial cells (ECs) and markedly induced by inflammatory stimuli such as TNF-α, IL-1β, and LPS. Overexpression of TRIM14 significantly increased the expression of adhesion molecules such as VCAM-1, ICAM-1, E-selectin, and cytokines such as CCL2, IL-8, CXCL-1, and TNF-α in activated ECs and by which it facilitated monocyte adhesion to ECs. Conversely, knockdown of TRIM14 has opposite effect on endothelial activation. Upon TNF-α stimulation, TRIM14 is recruited to IKK complex via directly binding to NEMO and promotes the phosphorylation of IκBα and p65, which is dependent on its K63-linked ubiquitination. Meanwhile, p65 can directly bind to the promoter regions of human TRIM14 gene and control its mRNA transcription. Finally, TRIM14 protein level is significantly upregulated in mouse and human atheroma compared to normal arteries. Taken together, these results indicate that TRIM14-NF-κB forms a positive feedback loop to enhance EC activation and TRIM14 may be a potential therapeutic target for vascular inflammatory diseases such as atherosclerosis.
基金supported by the Singapore National Research Foundation(NMRC/CSA/045/2012)administered by the Singapore Ministry of Health’s National Medical Research Council.
文摘Background:Gram-positive bacteria stimulate Toll-like receptor(TLR)2 and then activate the pro-inflammatory nuclear factor-kappa B(NF-κB)pathway.As the human ocular surface is heavily colonised by gram-positive cocci bacteria,a balance of activation/repression of NF-κB target genes is essential to avoid uncontrolled infection or autoimmune-related inflammation.It is advantageous to test NF-κB targeting molecules in an ocular surface culture system that allows assessment of temporal NF-κB activation in a longitudinal fashion without destruction of cells.Such initial testing under standardised conditions should reduce the number of molecules that progress to further evaluation in animal models.This study aims to establish an in-vitro cell culture system to assess NF-κB activation in the context of ocular surface cells.Methods:NF-κB activity was evaluated through a secretory alkaline phosphatase reporter assay(SEAP).Immunoblots and immunofluorescence were used to examine IκBαphosphorylation and p65/p50 nuclear localization.Monocyte chemoattractant protein-1(MCP-1)transcripts were evaluated by real time PCR and protein levels were measured by ELISA.Results:NF-κB activity in HCE-T cells treated with TLR2 activator Pam3CSK4 was higher than control cells at both 6 and 24 h.Pam3CSK4-stimulated NF-κB activation was inhibited by IκK inhibitors,Wedelolactone and BMS-345541.In Pam3CSK4 treated cells,active NF-κB subunits p50 and p65 increased in cell nuclear fractions as early as 1.5 h.Although the level of total IκB-αremained constant,phospho-IκB-αincreased with treatment over time.In the culture media of Pam3CSK4-stimulated cells,MCP-1 protein level was increased,which was suppressed in the presence of IκK inhibitors.Conclusion:NF-κB pathway can be activated by the TLR2 ligand and inhibited by IκK inhibitors in the ocular surface cell culture system.This cell culture system may be used to evaluate TLR-related innate defences in ocular surface diseases.
文摘Dear Editor,Chemotherapy is one of major means for cancer treatments, and many of chemotherapeutic drugs are DNA damaging agents that reduce tumor growth through triggering cancer cell apoptosis or necrosis. Following DNA damage, ataxia telangiectasia mutated (ATM), a protein kinase, was acti- vated and a cytosolic complex containing ATM, NEMO, RIP1 were formed (Biton and Ashkenazi, 2011).
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.30700417,30921001 and 31170835)the Ministry of Science and Technology of China(No.2012CB910201).
文摘The paracaspase MALT1 is essential for the activation of NF-κB in response to T cell receptor(TCR)stimula-tion.It recruits downstream TRAF6 and activates the E3 ligase activity of TRAF6 to polyubiquitinate several targets,which ultimately leads to NF-κB activation.Here we identified ubiquitin-specific protease 2a(USP2a)as a MALT1-associated protein by biochemical affinity purification.Endogenous USP2a constitutively interacted with TRAF6,but dynamically interacted with MALT1 and CARMA1 in a stimulation-dependent man-ner.RNA interference(RNAi)-mediated silencing of USP2a attenuated TCR-induced NF-κB activation and production of interleukin-2(IL-2).In addition,the ubiq-uitination of MALT1 and TRAF6 were both suppressed by USP2a knockdown.By knockdown and reconstitu-tion assays,we found that USP2a mediated the interac-tion between MALT1 and TRAF6 in a catalytic activ-ity-dependent manner.Furthermore,USP2a deSUMOy-lated TRAF6.Our findings implicate that USP2a plays an important role in TCR signaling by deSUMOylating TRAF6 and mediating TRAF6-MALT1 interaction.
基金This work was supported by grants from the National Natural Science Foundation of China (91629101, 31522018, 31601135, 81302197, 81700557, and 31071046), the National Key Basic Research Program of China (2015CB859800 and 2014CB910800), and the 6uangdong Innovative Research Team Program (2011Y035).
文摘NF-κB signaling controls a large set of physiological processes ranging from inflammatory responses to cell death. Its activation is tightly regulated through controlling the activity and stability of multiple signaling components. Here, we identify that NF-κB activation is suppressed by an F-box protein, S-phase kinase associated protein 2 (SKP2). SKP2 deficiency enhanced NF-κB activation as well as the production of inflammatory cytokines. In addition, SKP2 potently blocked the NF-κB activation at the κB kinase (IKIO level. Mechanistic study further revealed that SKP2 functions as an adaptor to promote an interaction between active IKKβ and the autophagic cargo receptor p62 to mediate IKKβ degradation via selective autophasy. These findings identify a previously unrecognized role of SKP2 in NF-κB activation by which SKP2 acts as a secondary receptor to assist IKKβ delivery to autophagosomes for degradation in a p62-dependent manner.