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1.
Article in English | WPRIM | ID: wpr-879968

ABSTRACT

To investigate the effects of interleukin (IL)-17-mediated autophagy on the TNF receptor associated factor (TRAF6)/extracellular signal-regulated kinase (ERK)/p38 pathway and osteoclast differentiation. Mouse bone marrow-derived macrophages (BMM) were cultured with a medium containing 30 ng/mL macrophage colony stimulating factor and 50 ng/mL receptor activator of nuclear factor-kappa B ligard (RANKL), and IL-17 (0.01, 0.1, 1.0, 10 ng/mL) was added for intervention (IL-17 group). Tartrate-resistant acid phosphatase (TRAP) staining was used to observe TRAP positive multinucleated cells; phalloidin fluorescent staining was used to detect actin ring circumference; toluidine blue staining was used to analyze bone resorption lacuna formation. To further examine the mechanism of the effect of IL-17-mediated autophagy on the differentiation of osteoclasts, the control group used RANKL medium to culture mouse macrophage RAW264.7 cells, while the IL-17 group was treated with IL-17 (0.01, 0.1, 1.0, /mL). Western blot was used to detect the expression of autophagy-related proteins Beclin-1, microtubule-associated protein 1 light chain 3 (LC3) and osteoclast-related proteins c-fos and nuclear factor of activated T cell 1 (NFATc1) after treatment with different concentrations of IL-17. The expression of LC3, NFATc1, TRAF6/ERK/p38 signaling pathway related proteins were detected in IL-17 and autophagy inhibitor 3-MA group. The number of TRAP positive multinucleated cells, the circumference of the actin ring and the area of bone resorption lacuna in IL-17 group treated with IL-17 (0.01, 0.1, were significantly higher than those in the control group. In IL-17 treated RAW264.7 cells, the expression of c-fos, NFATc1, Beclin-1, LC3, TRAF6, p-ERK, and p-p38 was all significantly up-regulated (all 0.05). After treatment with the autophagy inhibitor 3-MA, the expression levels of LC3, NFATc1, TRAF6, p-ERK, and p-p38 all decreased significantly (all 0.05). IL-17 can promote the expression of autophagy proteins and enhance the differentiation ability of osteoclast precursor cells, and the TRAF6/ERK/p38 signaling pathway may be involved in this process.


Subject(s)
Animals , Autophagy , Bone Resorption , Cell Differentiation , Extracellular Signal-Regulated MAP Kinases , Interleukin-17 , Mice , NFATC Transcription Factors/metabolism , Osteoclasts/metabolism , RANK Ligand/metabolism , TNF Receptor-Associated Factor 6
2.
Immune Network ; : e16-2019.
Article in English | WPRIM | ID: wpr-764015

ABSTRACT

Sequestosome 1 (SQSTM1, p62), a ubiquitin binding protein, plays a role in cell signaling, oxidative stress, and autophagy. However, its functional role in inflammatory signaling is controversial. Recent studies have shown that p62 is negatively implicated in inflammatory responses. But, the precise molecular mechanisms by which p62 regulates inflammatory responses remain unclear. In this study, we report on a new regulatory role for p62 in TLR4-mediated signaling. p62 overexpression led to the suppression of NF-κB activation and the production of pro-inflammatory cytokines, TNF-α, IL-6, and IL-1β in response to TLR4 stimulation. In contrast, p62(−/−) mouse embryonic fibroblast (MEF) cells exhibited marked enhancement of NF-κB activation and production of pro-inflammatory cytokines by TLR4 stimulation, compared to p62(+/+) MEF cells. Additionally, the TLR4-induced activation of signal transduction was significantly augmented in p62(−/−) MEF cells, indicating that p62 was negatively implicated in TLR4-mediated signaling. Biochemical studies revealed that p62 interacted with the internal domain of evolutionarily conserved signaling intermediate in Toll pathways (ECSIT), which is critical for associating with the TNF receptor associated factor 6 (TRAF6)-ECSIT complex to activate NF-κB in TLR4 signaling. Interestingly, p62-ECSIT interaction inhibited the interaction between TRAF6 and ECSIT and attenuated the ubiquitination of ECSIT. Furthermore, upon LPS challenge, the mortality of p62(−/−) (p62-knockout) mice was markedly enhanced compared to p62(+/+) (p62 wild-type) mice. Taken together, our data demonstrate that p62 negatively regulated TLR4 signaling via functional regulation of the TRAF6-ECSIT complex.


Subject(s)
Animals , Autophagy , Carrier Proteins , Cytokines , Fibroblasts , Interleukin-6 , Mice , Mortality , Oxidative Stress , Signal Transduction , TNF Receptor-Associated Factor 6 , Toll-Like Receptor 4 , Ubiquitin , Ubiquitination
3.
Article in Chinese | WPRIM | ID: wpr-690128

ABSTRACT

<p><b>OBJECTIVE</b>To study the protective effect of lipoxin A4 (LXA4) against sepsis induced by lipopolysaccharide (LPS) in rats with obesity and its effect on the expression of Toll-like receptor 4 (TLR4) and TNF receptor-associated factor 6 (TRAF6) in the liver.</p><p><b>METHODS</b>A total of 60 male Sprague-Dawley rats aged three weeks were randomly divided into a normal group and an obesity group, with 30 rats in each group. A rat model of obesity was established by high-fat diet. Each of the two groups was further randomly divided into control group, sepsis group, and LXA4 group, and 8 rats were selected from each group. The rats in the control, sepsis, and LXA4 groups were treated with intraperitoneal injection of normal saline, LPS, and LXA4+LPS respectively. Twelve hours later, blood samples were collected from the heart and liver tissue samples were also collected. ELISA was used to measure the serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Western blot was used to measure the protein expression of TLR4 and TRAF6 in liver tissue. Quantitative real-time PCR was used to measure the mRNA expression of TLR4 and TRAF6.</p><p><b>RESULTS</b>After being fed with high-fat diet for 6 weeks, the obesity group had significantly higher average weight and Lee's index than the normal group (P<0.05). Compared with the normal group, the obesity group had significant increases in the serum levels of IL-6 and TNF-α (P<0.05). In the normal group or the obesity group, the sepsis subgroup had significant increases in the serum levels of IL-6 and TNF-α compared with the control subgroup (P<0.05), while the LXA4 subgroup had significant reductions in the two indices compared with the sepsis subgroup (P<0.05). Compared with the normal group, the obesity group had significant increases in the protein and mRNA expression of TLR4 and TRAF6 (P<0.05). In the normal group or the obesity group, the sepsis subgroup had significant increases in the protein and mRNA expression of TLR4 and TRAF6 compared with the control subgroup (P<0.05). Compared with the sepsis subgroup, the LXA4 subgroup had significant reductions in the protein and mRNA expression of TLR4 and TRAF6 (P<0.05).</p><p><b>CONCLUSIONS</b>LXA4 can reduce the serum levels of IL-6 and TNF-α and alleviate inflammatory response. LXA4 can inhibit the expression of TLR4 and TRAF6 in the liver of septic rats, possibly by inhibiting the TLR4 signaling pathway.</p>


Subject(s)
Animals , Humans , Interleukin-6 , Genetics , Metabolism , Lipoxins , Liver , Metabolism , Male , Obesity , Drug Therapy , Genetics , Metabolism , Rats , Rats, Sprague-Dawley , Sepsis , Drug Therapy , Genetics , Metabolism , Signal Transduction , TNF Receptor-Associated Factor 6 , Genetics , Metabolism , Toll-Like Receptor 4 , Genetics , Metabolism , Tumor Necrosis Factor-alpha , Genetics , Metabolism
4.
Article in English | WPRIM | ID: wpr-77209

ABSTRACT

PURPOSE: MicroRNAs (miRs) were recently recognized to be important for immune cell differentiation and immune regulation. However, whether miRs were involved in allergen-specific immunotherapy (SIT) remains largely unknown. This study sought to examine changes in miR-146a and T regulatory cells in children with persistent allergic rhinitis (AR) after 3 months of subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT). METHODS: Twenty-four HDM-sensitized children with persistent AR were enrolled and treated with SCIT (n=13) or SLIT (n=11) for 3 months. Relative miR-146a and Foxp3 mRNA expression, the TRAF6 protein level, and the ratio of post-treatment to baseline IL-10+CD4+ T cells between the SCIT and SLIT groups were examined in the peripheral blood mononuclear cells (PBMCs) of AR patients using quantitative reverse transcription polymerase chain reaction (qRT-PCR), flow cytometry, and Western blot analysis, respectively. Serum levels of IL-5 and IL-10 were determined using ELISA. RESULTS: After 3 months of SIT, both the TNSS and INSS scores were significantly decreased compared to the baseline value (P<0.01). The relative expression of miR-146a and Foxp3 mRNA was significantly increased after both SCIT and SLIT (P<0.01). The ratio of post-treatment to baseline IL-10+CD4+ T cells and the serum IL-10 level were significantly increased in both the SCIT and SLIT groups (P<0.01), whereas the TRAF6 protein level and serum IL-5 level were significantly decreased (P<0.01). No significant differences in these biomarkers were observed between the SCIT and SLIT groups. CONCLUSIONS: Our findings suggest that miR-146a and its related biomarkers may be comparably modulated after both SCIT and SLIT, highlighting miR-146a as a potential therapeutic target for the improved management of AR.


Subject(s)
Biomarkers , Blotting, Western , Cell Differentiation , Child , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Humans , Immunotherapy , Interleukin-10 , Interleukin-5 , MicroRNAs , Polymerase Chain Reaction , Reverse Transcription , Rhinitis , RNA, Messenger , Sublingual Immunotherapy , T-Lymphocytes , TNF Receptor-Associated Factor 6
5.
Chinese Medical Journal ; (24): 1674-1681, 2016.
Article in English | WPRIM | ID: wpr-251322

ABSTRACT

<p><b>BACKGROUND</b>Despite its high prevalence, morbidity, and mortality, sepsis-associated encephalopathy (SAE) is still poorly understood. The aim of this prospective and observational study was to investigate the clinical significance of calcium-binding protein A8 (S100A8) in serum and tumor necrosis factor receptor-associated factor 6 (TRAF6) in peripheral blood mononuclear cells (PBMCs) in diagnosing SAE and predicting its prognosis.</p><p><b>METHODS</b>Data of septic patients were collected within 24 h after Intensive Care Unit admission from July 2014 to March 2015. Healthy medical personnel served as the control group. SAE was defined as cerebral dysfunction in the presence of sepsis that fulfilled the exclusion criteria. The biochemical indicators, Glasgow Coma Scale, Acute Physiology and Chronic Health Evaluation score II, TRAF6 in PBMC, serum S100A8, S100β, and neuron-specific enolase were evaluated in SAE patients afresh. TRAF6 and S100A8 were also measured in the control group.</p><p><b>RESULTS</b>Of the 57 enrolled patients, 29 were diagnosed with SAE. The S100A8 and TRAF6 concentrations in SAE patients were both significantly higher than that in no-encephalopathy (NE) patients, and higher in NE than that in controls (3.74 ± 3.13 vs. 1.08 ± 0.75 vs. 0.37 ± 0.14 ng/ml, P < 0.01; 3.18 ± 1.55 vs. 1.02 ± 0.63 vs. 0.47 ± 0.10, P < 0.01). S100A8 levels of 1.93 ng/ml were diagnostic of SAE with 92.90% specificity and 69.00% sensitivity in the receiver operating characteristic (ROC) curve, and the area under the curve was 0.86 (95% confidence interval [CI]: 0.76-0.95). TRAF6-relative levels of 1.44 were diagnostic of SAE with 85.70% specificity and 86.20% sensitivity, and the area under the curve was 0.94 (95% CI: 0.88-0.99). In addition, S100A8 levels of 2.41 ng/ml predicted 28-day mortality of SAE with 90.00% specificity and 73.70% sensitivity in the ROC curve, and the area under the curve was 0.88. TRAF6 relative levels of 2.94 predicted 28-day mortality of SAE with 80.00% specificity and 68.40% sensitivity, and the area under the curve was 0.77. Compared with TRAF6, the specificity of serum S100A8 in diagnosing SAE and predicting mortality was higher, although the sensitivity was low. In contrast, the TRAF6 had higher sensitivity for diagnosis.</p><p><b>CONCLUSIONS</b>Peripheral blood levels of S100A8 and TRAF6 in SAE patients were elevated and might be related to the severity of SAE and predict the outcome of SAE. The efficacy and specificity of S100A8 for SAE diagnosis were superior, despite its weak sensitivity. S100A8 might be a better biomarker for diagnosis of SAE and predicting prognosis.</p>


Subject(s)
Adult , Aged , Biomarkers , Blood , Calgranulin A , Blood , Calmodulin , Blood , Female , Humans , Male , Middle Aged , Prospective Studies , S100 Calcium Binding Protein beta Subunit , Blood , Sepsis-Associated Encephalopathy , Blood , Diagnosis , TNF Receptor-Associated Factor 6 , Blood
6.
Article in English | WPRIM | ID: wpr-289911

ABSTRACT

<p><b>OBJECTIVE</b>To explore the effect of MiR-146a regulator function on the inflammatory response in neuroglia cell (microglia).</p><p><b>METHODS</b>BV2 cells were transfected by MiR-146a mimics,and then stimulated by lipopolysaccharide (LPS). MiR-146a expression was measured by real-time polymerase chain reaction (real-time PCR). Interleukin (IL)-6 and tumor necrosis factor α (TNFα) were measured by enzyme-linked immunosorbent assay (ELISA). Furthermore, IL-1 receptor-associated kinase 1 (IRAK1) and TNF receptor-associated factor 6 (TRAF6) were detected by PCR and Western blotting.</p><p><b>RESULTS</b>Compared to the normal control group, MiR-146a expression was significantly elevated by transfection with MiR-146a mimics (t=5.846, P=0.0021). The expression levels of IRAK1, TRAF6, TNFα, and IL-6 significantly increased in the LPS-stimulated BV2 cells compared to the non-stimulated BV2. The enhancement of MiR-146a resulted in significantly decreased IL-6 (t=5.200, P=0.0003) and TNFα (t=9.812, P<0.0001) secretion. The mRNA (t=5.353, P=0.0007) and protein (t=6.980, P=0.0009) levels of TRAF6, but not IRAK1, also significantly decreased.</p><p><b>CONCLUSION</b>MiR-146a may negatively suppress the inflammatory response of BV2 cells by regulating the expression of IRAF6 molecules in the TLR4 signaling pathway.</p>


Subject(s)
Blotting, Western , Cell Line , Enzyme-Linked Immunosorbent Assay , Humans , Inflammation , Interleukin-1 Receptor-Associated Kinases , Interleukin-6 , Lipopolysaccharides , MicroRNAs , RNA, Messenger , Real-Time Polymerase Chain Reaction , Signal Transduction , TNF Receptor-Associated Factor 6 , Transfection , Tumor Necrosis Factor-alpha
7.
Article in English | WPRIM | ID: wpr-331062

ABSTRACT

This study examined the mechanism of the inhibitory effect of parthenolide (PTL) on the activity of NF-κB in multiple myeloma (MM). Human multiple myeloma cell line RPMI 8226 cells were treated with or without different concentrations of PTL for various time periods, and then MTT assay was used to detect cell proliferation. Cell cycle and apoptosis were flow cytometrically detected. The level of protein ubiquitination was determined by using immunoprecipitation. Western blotting was employed to measure the level of total protein ubiquitination, the expression of IκB-α in cell plasma and the content of p65 in nucleus. The content of p65 in nucleus before and after PTL treatment was also examined with immunofluorescence. Exposure of RPMI 8226 cells to PTL attenuated the level of ubiquitinated Nemo, increased the expression of IκB-α and reduced the level of p65 in nucleus, finally leading to the decrease of the activity of NF-κB. PTL inhibited cell proliferation, induced apoptosis and blocked cell cycle. Furthermore, the levels of ubiquitinated tumor necrosis factor receptor-associated factor 6 (TRAF6) and total proteins were decreased after PTL treatment. By using Autodock software package, we predicted that PTL could bind to TRAF6 directly and tightly. Taken together, our findings suggest that PTL inhibits the activation of NF-κB signaling pathway via directly binding with TRAF6, thereby suppressing MM cell proliferation and inducing apoptosis.


Subject(s)
Apoptosis , Cell Cycle , Cell Line, Tumor , Cell Proliferation , Humans , Multiple Myeloma , Drug Therapy , Metabolism , NF-kappa B , Blood , Sesquiterpenes , Pharmacology , TNF Receptor-Associated Factor 6 , Metabolism , Transcription Factor RelA , Metabolism , Ubiquitination
8.
Article in Chinese | WPRIM | ID: wpr-237866

ABSTRACT

<p><b>OBJECTIVE</b>To study the effect of Buyang Huanwu Decoction (BHD), Xuefu Zhuyu Decoction (XZD), and Sijunzi Decoction (SD) contained serums on expressions of Toll-like receptor 4 (TLR4)/nuclear factor (NF)-κB signals, lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), tumor necrosis factor-α (TNF-α), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and to explore possible anti-atherosclerotic mechanisms.</p><p><b>METHODS</b>Twenty New Zealand rabbits were divided into 4 groups at random, i.e., the normal control group, the BHD group (6.7 g/kg), the XZD group (3.6 g/kg), and the SD group (1.6 g/kg), 5 in each group. All medication lasted for 7 successive days. Two h after the final medication, about 50 mL blood was withdrawn from rabbit heart for preparing serums. Human umbilical vein endothelial cell ECV304 were cultured in vitro for 18 h and randomly divided into the blank control group, the model group, the Western medicine (WM) control group, the BHD group, the XZD group, and the SD group at random. ECV304, except in the blank control group, were stimulated with lipopolysaccharide (LPS) for 2 h. Those in the WM control group and CM groups were treated respectively with corresponding CM contained serum for 24 h. Finally gene and protein expressions of TLR4, myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor-associated factor-6 (TRAF-6), NF-κB, LOX-1, TNF-α, ICAM-1, and VCAM-1 were detected by fluorescent quantitative PCR and Western blot.</p><p><b>RESULTS</b>Compared with the blank control group, mRNA expressions of TLR4, MyD88, TRAF-6, NF-KB, LOX-1 , TNF-cx, ICAM-1, and VCAM-1 increased significantly; protein expressions of TLR4, NF-κB, LOX-1, TNF-α, ICAM-1, and VCAM-1 also increased significantly in the model group (P < 0.01). Compared with the model group, mRNA and protein expressions of each index could be significantly inhibited in the BHD group, the XZD group, and the WM control group (P < 0.05). Besides, mRNA and protein expressions of each index could be significantly elevated more in the BHD group and the XZD group than in the WM control group (P < 0.05). No statistical difference existed in each index between the SD group and the rest groups (P > 0.05).</p><p><b>CONCLUSIONS</b>The mechanism of BHD and XZD for fighting against atherosclerosis might be associated with inhibiting TLR4/NF-κB signal transduction pathway and expressions of its downstream inflammatory factors such as LOX-1, TNF-α, ICAM-1, and VCAM-1. But SD showed no associated effect on atherosclerosis.</p>


Subject(s)
Animals , Atherosclerosis , Drug Therapy , Drugs, Chinese Herbal , Pharmacology , Therapeutic Uses , Endothelial Cells , Intercellular Adhesion Molecule-1 , Metabolism , Lipopolysaccharides , Myeloid Differentiation Factor 88 , Metabolism , NF-kappa B , Metabolism , Rabbits , Scavenger Receptors, Class E , Signal Transduction , TNF Receptor-Associated Factor 6 , Metabolism , Toll-Like Receptor 4 , Metabolism , Tumor Necrosis Factor-alpha , Metabolism , Umbilical Veins , Vascular Cell Adhesion Molecule-1 , Metabolism
9.
Article in English | WPRIM | ID: wpr-250400

ABSTRACT

Liopxin A4 (LXA4) is considered to be a crucial modulator in the inflammatory responses. In the present study, we aimed to study the effect of LXA4 on the inflammatory cytokines production induced by lipopolysaccharide (LPS) and the possible mechanism in normal human epidermal keratinocytes (NHEKs). NHEKs were isolated and cultured. The expression of toll-like receptor 4 (TLR4), LXA4 receptor (ALXR) and aryl hydrocarbon receptor (AhR) in NHEKs was detected by reverse transcription polymerase chain reaction (RT-PCR). The mRNA and protein levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1β (IL-1β) were determined in NHEKs stimulated by LPS (10 μg/mL) with or without preincubation with LXA4 (100 nmol/L) for 30 min by real-time quantitative PCR (real-time qPCR) and enzyme-linked immunosorbent assay (ELISA), respectively. The expression levels of tumor necrosis factor receptor-associated factor 6 (TRAF6) and suppressors of cytokine signaling 2 (SOCS2) mRNAs and proteins, and nuclear translocation of NF-kB-p65 were measured by real-time qPCR and Western blotting, respectively. The results showed that NHEKs expressed TLR4, ALXR and AhR. LXA4 significantly inhibited the mRNA and protein expression levels of TNF-α, IL-1β and TRAF6 induced by LPS in NHEKs, and LXA4 obviously increased the expression of SOCS2 at mRNA and protein levels. The nuclear NF-kB-p65 protein expression induced by LPS was inhibited after preincubation with LXA4 in NHEKs. It was concluded that LXA4 inhibits the LPS-induced production of TNF-α and IL-1β in NHEKs by up-regulating SOCS2 and down-regulating TRAF6.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal , Pharmacology , Cells, Cultured , Gene Expression Regulation , Humans , Keratinocytes , Lipopolysaccharides , Pharmacology , Lipoxins , Pharmacology , NF-kappa B , Genetics , Metabolism , Suppressor of Cytokine Signaling Proteins , Genetics , Metabolism , TNF Receptor-Associated Factor 6 , Genetics , Metabolism , Toll-Like Receptor 4 , Genetics , Metabolism , Tumor Necrosis Factor-alpha , Genetics , Metabolism
10.
Article in English | WPRIM | ID: wpr-250389

ABSTRACT

Endothelial dysfunction induced by intermittent hypoxia (IH) participates in obstructive sleep apnea syndrome (OSAS)-associated cardiovascular disorders. Myeloid differentiation primary response 88 (MyD88) and tumor necrosis factor receptor-associated factor 6 (TRAF6) regulate numerous downstream adaptors like mitogen-activated protein kinases (MAPKs) and the subsequent oxidative stress and inflammatory responses. This study aimed to characterize the role of MyD88/TRAF6 in IH-treated cell function and its associated signaling. Human umbilical vein endothelial cells (HUVECs) were randomly exposed to IH or normoxia for 0, 2, 4 and 6 h. Western blotting was used to detect the expression pattern of target gene proteins [angiotensin 1 receptor (AT1R), p-ERK1/2, p-p38MAPK, MyD88 and TRAF6], and the relationships among these target genes down-regulated by the corresponding inhibitors were studied. Finally, the influence of these target genes on proliferation of HUVECs was also assessed by EdU analysis. Protein levels of AT1R, TRAF6 and p-ERK1/2 were increased after IH exposure, with a slight rise in MyD88 and a dynamic change in p-p38MAPK. The down-regulation of TRAF6 by siRNA reduced ERK1/2 phosphorylation during IH without any effects on AT1R. Blockade of AT1R with valsartan decreased TRAF6 and p-ERK1/2 protein expression after IH exposure. ERK1/2 inhibition with PD98059 suppressed only AT1R expression. IH promoted HUVECs proliferation, which was significantly suppressed by the inhibition of TRAF6, AT1R and ERK1/2. The findings demonstrate that TRAF6 regulates the proliferation of HUVECs exposed to short-term IH by modulating cell signaling involving ERK1/2 downstream of AT1R. Targeting the AT1R-TRAF6-p-ERK1/2 signaling pathway might be helpful in restoring endothelial function.


Subject(s)
Cell Hypoxia , Cell Proliferation , Cells, Cultured , Gene Expression Regulation , Human Umbilical Vein Endothelial Cells , Physiology , Humans , MAP Kinase Signaling System , Phosphorylation , Receptor, Angiotensin, Type 1 , Genetics , Metabolism , TNF Receptor-Associated Factor 6 , Genetics , Metabolism , Valsartan , Pharmacology
11.
Article in English | WPRIM | ID: wpr-51351

ABSTRACT

BACKGROUND/OBJECTIVES: Carnosic acid (CA), found in rosemary (Rosemarinus officinalis) leaves, is known to exhibit anti-obesity and anti-inflammatory activities. However, whether its anti-inflammatory potency can contribute to the amelioration of obesity has not been elucidated. The aim of the current study was to investigate the effect of CA on Toll-like receptor 4 (TLR4) pathways in the presence of lipopolysaccharide (LPS) in 3T3-L1 adipocytes. MATERIALS/METHODS: 3T3-L1 adipocytes were treated with CA (0-20 microM) for 1 h, followed by treatment with LPS for 30 min; mRNA expression of adipokines and protein expression of TLR4-related molecules were then measured. RESULTS: LPS-stimulated 3T3-L1 adipocytes showed elevated mRNA expression of tumor necrosis factor (TNF)-alpha, interleukin-6, and monocyte chemoattractant protein-1, and CA significantly inhibited the expression of these adipokine genes. LPS-induced up regulation of TLR4, myeloid differentiation factor 88, TNF receptor-associated factor 6, and nuclear factor-kappaB, as well as phosphorylated extracellular receptor-activated kinase were also suppressed by pre-treatment of 3T3-L1 adipocytes with CA. CONCLUSIONS: Results of this study suggest that CA directly inhibits TLR4-MyD88-dependent signaling pathways and decreases the inflammatory response in adipocytes.


Subject(s)
Adipocytes , Adipokines , Chemokine CCL2 , Inflammation , Interleukin-6 , Myeloid Differentiation Factor 88 , Obesity , Phosphotransferases , RNA, Messenger , TNF Receptor-Associated Factor 6 , Toll-Like Receptor 4 , Tumor Necrosis Factor-alpha , Up-Regulation
12.
Journal of Experimental Hematology ; (6): 1301-1305, 2014.
Article in Chinese | WPRIM | ID: wpr-340509

ABSTRACT

This study was purposed to detect the expression levels of TRAF6, TAK1 and TGF-β mRNA in peripheral blood mononuclear cell (PBMNC) of patients with diffuse large B cell lymphoma (DLBCL) before and after chemotherapy, and to explore the effect of chemotherapy on the activity of TRAF6/TAK1 signal pathway. The expression levels of TRAF-6, TAK1 and TGF-β mRNA in PBMNC of 38 patients with DLBCL were detected by using the quantitative real time PCR before treatment or after two cycles of chemotherapy, 12 healthy people were served as the control. The results showed that the expression levels of TRAF-6, TAK1 and TGF-β mRNA in PBMNC of DLBCL patients' were higher than those in healthy people. Before treatment, the expression levels of TRAF-6 and TAK1 mRNA had no significant difference as compared with healthy people (P > 0.05); after chemotherapy, the expression levels of these two genes significantly increased, and the differences both had statistically significant as compared with healthy people (P < 0.05); meanwhile the increased expression levels of these two genes after chemotherapy had statistically significant difference as compared with levels before treatment (P < 0.05) , and those expression levels were positively correlated. While the expression level of TGF-β mRNA decreased after chemotherapy as compared with level before treatment, and the differences had statistically significantse(P < 0.05). It is concluded that the activity of TRF6/TAK1 signal pathways in PBMNC of DLBCL patients' significantly increases after chemotherapy, while the expression level of TGF-β mRNA after chemotherapy is abviously lower than level before treatment.


Subject(s)
Gene Expression Regulation, Leukemic , Humans , Leukocytes, Mononuclear , Metabolism , Lymphoma, Large B-Cell, Diffuse , Drug Therapy , Genetics , MAP Kinase Kinase Kinases , Genetics , RNA, Messenger , Genetics , Signal Transduction , TNF Receptor-Associated Factor 6 , Genetics , Transforming Growth Factor beta , Genetics
13.
Article in English | WPRIM | ID: wpr-351019

ABSTRACT

Osteonecrosis of the femoral head is frequently observed in patients treated with excessive corticosteroids. However, the pathogenesis of corticosteroid-induced osteonecrosis remains unclear. The purpose of this study was to investigate the role of Toll-like receptor 4 (TLR4) signaling pathway in steroid-induced femoral head osteonecrosis in rats. Male Sprague-Dawley rats were injected intramuscularly with 20 mg/kg methylprednisolone (MP) for 8 weeks, twice per week. The animals were sacrificed at 2, 4 and 8 weeks after the last MP injection, respectively, and then allocated to the 2-, 4- and 8-week model groups (n=24 each). Rats in the control group (n=12) were not given any treatment. Histopathological analysis was performed and the concentration of tartrate-resistant acid phosphatase (TRAP) in plasma was determined. The activation of osteoclasts in the femoral head was assessed by TRAP staining. The expression of TLR4, MyD88, TRAF6 and NF-κB p65 that are involved in TLR4 signaling, and MCP-1 production were detected by using real-time PCR (RT-PCR) and Western blotting. The results showed that the osteonecrosis in the femoral head was clearly observed and the concentration of TRAP in the plasma was increased in the model rats. The femoral head tissues in MP-treated rats were positive for TRAP and the intensity of TRAP staining was greater in MP-treated rats than in control rats. As compared with the control group, the mRNA expression of TLR4 signaling-related factors was enhanced significantly at 4 and 8 weeks, and the protein levels of these factors increased significantly with time. It was concluded that MP could induce the femoral head osteonecrosis in rats, which was associated with osteoclast activation via the TLR4 signaling pathway. These findings suggest that TLR4 signaling pathway plays a pivotal role in the pathogenesis of steroid-induced osteonecrosis.


Subject(s)
Acid Phosphatase , Metabolism , Animals , Blotting, Western , Chemokine CCL2 , Genetics , Metabolism , Femur Head , Metabolism , Pathology , Gene Expression , Immunohistochemistry , Isoenzymes , Metabolism , Male , Methylprednisolone , Myeloid Differentiation Factor 88 , Genetics , Metabolism , Osteonecrosis , Genetics , Metabolism , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , TNF Receptor-Associated Factor 6 , Genetics , Metabolism , Tartrate-Resistant Acid Phosphatase , Time Factors , Toll-Like Receptor 4 , Genetics , Metabolism , Transcription Factor RelA , Genetics , Metabolism
14.
Chinese Journal of Stomatology ; (12): 428-433, 2014.
Article in Chinese | WPRIM | ID: wpr-260806

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of small interfering RNA (siRNA)-mediated inhibition of tumor necrosis factor receptor associated factor 6(TRAF6) gene on murine odontoblast-like cell line, MDPC-23 cell and the effect of TRAF6 on MDPC-23 cell proliferation.</p><p><b>METHODS</b>The vectors expressing siRNA against TRAF6 were constructed and introduced into MDPC-23 cell with lipofectin , and the cell line with stable expression of siRNA of TRAF6 was obtained by G418 screening and colony culture. Reverse transcription-PCR (RT-PCR) and Western blotting were performed to detect the expression of TRAF6. The proliferation of transfected MDPC-23 cell was investigated through methabenzthiazuron (MTT) and flow cytometry (FCM) assay.</p><p><b>RESULTS</b>The positive single colony was screened out, and was found to express siRNA against TRAF6 effectively because both TRAF6 mRNA and protein relative expression were significantly decreased in the experimental group (pSUPER-TRAF6siRNA: mRNA 0.163 ± 0.008, protein 0.215 ± 0.006) compared with controls (pSUPER: mRNA 0.778 ± 0.017, protein 0.964 ± 0.007 (P < 0.001). The A value of treated pSUPER-TRAF6siRNA cells (3 d: 0.46 ± 0.03, 5 d: 1.35 ± 0.06) was increased compared with controls (P<0.01). The result of proliferation index (PrI) was also increased compared with controls [pSUPER- TRAF6siRNA: (24.1 ± 2.2)%; pSUPER (11.2 ± 1.0)%; control (10.5 ± 0.7)%, P < 0.01].</p><p><b>CONCLUSIONS</b>The transcription and expression of TRAF6 gene were inhibited. The proliferation ability was increased in MDPC-23 cells by the constructed pSUPER-TRAF6siRNA vector. It may further influence the formation and repair of dentin, and may be involved in the regulation of normal tooth eruption and process of dentin repair after injury.</p>


Subject(s)
Animals , Cell Line, Tumor , Cell Proliferation , Flow Cytometry , Gene Silencing , Genetic Vectors , Mice , Odontoblasts , Cell Biology , RNA, Messenger , RNA, Small Interfering , TNF Receptor-Associated Factor 6 , Genetics , Transfection
15.
Protein & Cell ; (12): 62-70, 2013.
Article in English | WPRIM | ID: wpr-757833

ABSTRACT

The paracaspase MALT1 is essential for the activation of NF-κB in response to T cell receptor (TCR) stimulation. 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 manner. RNA interference (RNAi)-mediated silencing of USP2a attenuated TCR-induced NF-κB activation and production of interleukin-2 (IL-2). In addition, the ubiquitination of MALT1 and TRAF6 were both suppressed by USP2a knockdown. By knockdown and reconstitution assays, we found that USP2a mediated the interaction between MALT1 and TRAF6 in a catalytic activity-dependent manner. Furthermore, USP2a deSUMOylated TRAF6. Our findings implicate that USP2a plays an important role in TCR signaling by deSUMOylating TRAF6 and mediating TRAF6-MALT1 interaction.


Subject(s)
Caspases , Metabolism , Endopeptidases , Genetics , Metabolism , Gene Knockdown Techniques , HEK293 Cells , Humans , Interleukin-2 , Jurkat Cells , Mucosa-Associated Lymphoid Tissue Lymphoma Translocation 1 Protein , NF-kappa B , Metabolism , Neoplasm Proteins , Metabolism , Receptors, Antigen, T-Cell , Metabolism , Signal Transduction , Sumoylation , TNF Receptor-Associated Factor 6 , Metabolism
16.
Article in Chinese | WPRIM | ID: wpr-358683

ABSTRACT

<p><b>OBJECTIVE</b>To investigate weather there is a toll-like receptor 4 (TLR4)-mediated myeloid differentiation factor 88 (MyD88)-dependent pathway in hippocampal neurons of rats and the probable role of the pathway in neuroinflammation.</p><p><b>METHODS</b>To establish the proper model, primarily cultured hippocampal neurons were treated with lipopolysaccharides (LPS), or pretreated with TLR4 antibody then co-treated with LPS. The expression of mRNA of MyD88 and TNF-alpha receptor associated factor 6 (TRAF6) were tested by RT-qPCR. The content of MyD88 and TRAF6 were tested by Western blot. The nuclear translocation of nuclear factor-kappaB/P65 (NF-kappaB/p65) was tested by immunofluorescence. The content of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and nitric oxide (NO) were tested by ELISA.</p><p><b>RESULTS</b>LPS could increase MyD88 and TRAF6 mRNA, upregulate protein level of MyD88 and TRAF6 and increase the level of TNF-alpha, IL-1beta and NO in cell culture supernatant. LPS also could promote NF-kappa B/p65 translation to the nucleus. The pretreatment with TLR4 antibody reduced the translocation to nucleus for NF-kappaB/P65 and the contents of TNF-alpha, IL-1beta and NO in the culture supernatant.</p><p><b>CONCLUSION</b>There is a TLR4-mediated MyD88-dependent pathway in hippocampal neurons. The activation of this pathway can increase the level of TNF-alpha, IL-1beta and NO in cell culture supernatant. TLR4-mediated MyD88-dependent pathway in hippocampal neurons participate in neuroinflammation, that means neurons are not passive in inflammation.</p>


Subject(s)
Animals , Cells, Cultured , Hippocampus , Cell Biology , Metabolism , Interleukin-1beta , Metabolism , Myeloid Differentiation Factor 88 , Metabolism , Neuritis , Metabolism , Neurons , Metabolism , Nitric Oxide , Metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction , TNF Receptor-Associated Factor 6 , Metabolism , Toll-Like Receptor 4 , Metabolism , Transcription Factor RelA , Metabolism , Tumor Necrosis Factor-alpha , Metabolism
17.
Chinese Journal of Hematology ; (12): 941-945, 2013.
Article in Chinese | WPRIM | ID: wpr-295767

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the down-regulated TRAF6 gene expression and its effects on proliferation and apoptosis in multiple myeloma (MM) cells.</p><p><b>METHODS</b>Detection of TRAF6 expression were conducted by RT-PCR and Western blot in MM cell lines of KM3, U266, RPMI8226 and primary cells from patients. RPMI8226 cell lines were transfected with siRNA of TRAF6. The efficiency of transfection was identified by using of fluorescence microscope, RT-PCR, and Western blot. The levels of proliferation were analyzed by CCK-8 method under the different concentrations of siRNA. Apoptosis rate were detected with Hoechst33258/PI double staining by flow cytometry. Apoptosis related proteins Bcl-2, BAX, and NF-κB signal pathway were observed before and after siRNA transfection by Western blot.</p><p><b>RESULTS</b>The levels of TRAF6 mRNA and protein in MM cell lines, especially in primary myeloma cells, were significantly higher than those in controls. After transfected with 50 nmol/L siRNA in RPMI8226 cells, the relative level of TRAF6 mRNA (0.49±0.24) was significantly lower than that in non-transfected group (1.87±0.23) and idling group (1.74±0.35). The proliferation rate of siRNA transfected cells decreased with dose dependence (P<0.01). The apoptosis rates increased from 11.20% (before transfection) to 51.82% (after transfection), accompanied by down-regulated Bcl-2 protein, NF-κB signal pathway (p-p65 and p52), and up-regulated BAX protein.</p><p><b>CONCLUSION</b>TRAF6 expression was high in myeloma cells. TRAF6 siRNA could inhibit proliferation of myeloma cells and induce apoptosis mediated by NF-κB classical and alternative pathway in myeloma cells.</p>


Subject(s)
Case-Control Studies , Cell Proliferation , Down-Regulation , Female , Gene Expression , Humans , Male , Multiple Myeloma , Metabolism , Pathology , TNF Receptor-Associated Factor 6 , Genetics , Metabolism , Tumor Cells, Cultured
18.
Article in Chinese | WPRIM | ID: wpr-313254

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the influence of Yiqi Huoxue Recipe (YHR) containing drug-serum on the expression of Toll-like receptor-4 (TLR4) and its downstream signaling components MyD88, as well as the tumor necrosis factor receptor related factor-6 (TRAF-6) in human vein endothelial cells (HUVECs) induced by lipopolysaccharide (LPS), and to study its possible anti-atherosclerotic mechanism from the gene and protein levels.</p><p><b>METHODS</b>Twenty New Zealand male rabbits were equally divided into four groups in random: the normal control group and the three YHR groups, 5 in each group. They were gastric perfused daily with normal saline and YHR in low, moderate and high concentration respectively. Blood drawn from rabbits' heart 2 h after ending perfusion on the 7th day, and the serum separated (that is the drug-serum) was taken for testing. HUVECs were cultured in vitro and equally divided into six groups in random: the normal control group, the model group, the Western medicine group and the three YHR groups. HUVECs were stimulated with LPS, then treated separately with the drug-serum containing different concentrations of YHR for 24 h. Then the mRNA expressions of TLR4, MyD88 and TRAF-6 were measured with Real-time PCR, and their protein expressions were analyzed using Western blotting.</p><p><b>RESULTS</b>Protein and mRNA expressions of TLR4, MyD88 and TRAF-6 increased significantly after LPS stimulation (P < 0.01), but the changes in the drug-serum treated groups were significantly lower than those in the saline control group respectively (P < 0.01 or P < 0.05).</p><p><b>CONCLUSION</b>YHR can block the high expression of TLR4, and also influence the MyD88-dependent signaling pathway of TLR4, suppress the downstream expression of NF-kappaB and various related gene expressions, which may be one of its mechanisms of action for anti-atherosclerosis.</p>


Subject(s)
Animals , Drugs, Chinese Herbal , Pharmacology , Human Umbilical Vein Endothelial Cells , Metabolism , Humans , Male , Myeloid Differentiation Factor 88 , Metabolism , Rabbits , Serum , TNF Receptor-Associated Factor 6 , Metabolism , Toll-Like Receptor 4 , Metabolism
19.
Article in Chinese | WPRIM | ID: wpr-285410

ABSTRACT

<p><b>OBJECTIVE</b>Based on relevent theory of prescription and syndrome, to compare the gene expression differences of TLR2, TRAF6, and Faslg with adjuvant arthritis in rat spleen among Wutou decoction, Guizhi Shaoyao Zhimu decoction and Baihu Guizhi decoction.</p><p><b>METHOD</b>The experiment animal model of adjuvant arthritis in rats was established. Relative expression amount of TLR2, TRAF6, and Faslg in rats spleen was detected by SYBR Green I dye methods and implementation of fluorescence quantitative PCR technology with 18sRNA as an internal gene. 2(delta delta CT) method was used for computing and data analysis.</p><p><b>RESULT</b>TLR2, TRAF6, and Faslg gene in adjuvant arthritis rat spleen was significantly higher than those in the blank group. The various doses of Wutou decoction, Guizhi Shaoyao Zhimu decoction and Baihu Guizhi decoction can significantly inhibit or reduce the abnormally high expression of TLR2, TRAF6, and Faslg genes. The gene expression level caused by three decoctions mentioned above was followed by strong to weak as Wutou decoction Guizhi Shaoyao Zhimu decoction and Baihu Guizhi decoction with the clinical equivalent dose, but the strength of the trend to reduce the role of TRAF6 is just the opposite with the TLR2 and Faslg genes.</p><p><b>CONCLUSION</b>Wutou decoction, Guizhi Shaoyao Zhimu decoction and Baihu Guizhi decoction can reduce the abnormally high expression of TLR2, TRAF6 and Faslg in rat spleen with adjuvant arthritis, but the differences of intensity exist and remain relatively consistent with that of pharmacodynamics and regulation trends of T cell subsets. Results suggest that the suppression of TLR2/TRAF6 signal pathway and apoptosis Faslg receptor gene may be the reasons that the pharmacodynamics of three decoctions on peripheral T cell subsets in regulating intensity was different.</p>


Subject(s)
Animals , Arthralgia , Drug Therapy , Genetics , Metabolism , Pathology , Calibration , Drugs, Chinese Herbal , Pharmacology , Therapeutic Uses , Fas Ligand Protein , Genetics , Metabolism , Gene Expression Regulation , Male , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , TNF Receptor-Associated Factor 6 , Genetics , Metabolism , Toll-Like Receptor 2 , Genetics , Metabolism
20.
Article in Chinese | WPRIM | ID: wpr-281726

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the influence of Dureping injection to the murinal celiac macrophage Ana-1 on TIR signal pathway.</p><p><b>METHOD</b>Ana-1 cell line was infected by influenza virus FM1 strain and treated with the Dureping injection in different concentrations (10.1 mg x L(-1) group) for 12 h and 24 h. Then we collected the cells, extracted mRNA and measured the expressions of TLR7, MyD88, IRAK4, TRAF6 and NF-kappaB p65 respectively by RT-PCR.</p><p><b>RESULT</b>Dureping injection down-regulated the expression of TLR7, MyD88, IRAK4, TRAF6 and NF-kappaB p65 mRNA in Ana-1 cell line infected by influenza virus, in a dose-dependent manner significantly.</p><p><b>CONCLUSION</b>Dureping injection has an obvious effect against influenza virus FM1 strain by regulating the TIR signal pathway.</p>


Subject(s)
Adaptor Proteins, Signal Transducing , Animals , Cells , Cells, Cultured , Epithelial Cells , Metabolism , Interleukin-1 Receptor-Associated Kinases , Genetics , Macrophages , Metabolism , Mice , Myeloid Differentiation Factor 88 , Genetics , Metabolism , NF-kappa B , Metabolism , RNA, Messenger , Metabolism , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , TNF Receptor-Associated Factor 6 , Genetics , Metabolism , Transcription Factor RelA , Metabolism
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