Dual Effect of 3, 4- Dihydroxyacetophenone on LPS-induced Apoptosis in RAW264.7 Cells by Modulating the Production of TNF-α

Summary: To explore the pharmacological effect of 3,4-dihydroxyacetophenone (DHAP) on the apoptosis of RAW264.7 macrophage cells and the mechanism, RAW264.7 macrophage cells were treated with 100 or 500 mg/L lipopolysaccharide (LPS), with or without 10 -5 mol/L DHAP for 24 h. Trypan blue dye exclusion assay was used to assess cell viability. Cell apoptosis was morphological studied and flow cytometric assay was used. Tumor necrosis factor-α (TNF-α) level was measured by ELISA methods. IκB protein was determined by Western blotting. Our results showed that in 100 mg/L LPS-stimulated macrophages, DHAP enhanced the cell apoptosis while in 500 mg/L LPS-stimulated macrophages, DHAP significantly inhibited the cell apoptosis. In both groups, DHAP increased the level of IκB but decreased the level of TNF-α. It is concluded that DHAP has dual effect on the apoptosis of RAW 264.7 cells treated with different concentrations of LPS. This effect may be due to the inhibition of activation of NF-κB and autocrine production of TNFα. Our study suggests that DHAP may have anti-inflammatory effect on LPS-activated macrophages.

Modulation of Interleukin-15-induced Suppression of Human Neutrophil Apoptosis by TNFα

Human interleukin-15 （IL-15） is a proinflammatory cytokine to suppress neutrophil apoptosis, which is a potential therapeutic agent. The modulatory effect of TNFα was investigated in IL-15-induced suppression of human neutrophil apoptosis. TNFa was shown to reverse the ability of IL-15 to delay neutrophil apoptosis within certain time course. Moreover, this reverse effect by TNFα might be associated with a reduction of the expression of the anti-apoptotic Bcl-XI protein detected by Western blotting. It is concluded that TNFα can be used to modulate IL- 15-induced suppression of neutrophil apoptosis within certain time course.

Effects of nuclear translocation of tissue transglutaminase and the release of cytochrome C on hepatocyte apoptosis

Objective To assess the effects of nuclear translocation of tissue transglutaminase (TTG) and the release of cytochrome C on hepatocyte apoptosis and to reveal the mechanism of signal transduction of early apoptosis in injured hepatocytes. Methods Hepatocytes isolated from tissue transglutaminase gene knock-out mice and rats were stimulated with ethanol. Proteins from whole cell, cytoplasm and nuclei were extracted for determination of TTG activity by 14C-putrescine incorporation. Distribution of TTG throughout the entire cell, as well as just nucleus was observed under a confocal scanning microscope. The amount of cytochrome C released from mitochondria was determined by ELISA. Cell apoptosis was observed by fluorescent cytochemistry.Results TTG activity in whole cells and nuclei was significantly increased after the hepatocytes were treated with ethanol. Cytochrome C release was remarkably increased in the cells isolated from rat and wild-type mouse after treatment with ethanol but not in TTG gene knock-out mice. Cellular apoptosis appeared in hepatocytes isolated from rats and wild-type mice but not in the hepatocytes from TTG gene knock-out mice after stimulation with ethanol.Conclusions Increased TTG in hepatocytes can be translocated into the nucleus and promote release of mitochondrial cytochrome C into the cytoplasm. Passing through a series of signal pathways, hepatocyte apoptosis is induced eventually.

Effects of TNFAIP3 and PDE4B on apoptosis and invasion of tumor cells in diffuse large B cell lymphoma

Objective: To study the effects of TNFAIP3 and PDE4B on apoptosis and invasion of tumor cells in diffuse large B cell lymphoma. Methods: A total of 68 patients who were diagnosed with diffuse large B cell lymphoma in Guangzhou 421 Hospital of PLA between August 2014 and July 2017 were selected as the DLBCL group of the study, and 34 patients who accepted lymph node biopsy due to lymphadenectasis and were diagnosed with reactive lymphoid hyperplasias in Guangzhou 421 Hospital of PLA during the same period were selected as the control group. The expression levels of TNFAIP3, PDE4B, apoptosis genes and invasion genes in lymph node tissue were determined. Results: TNFAIP3, PTEN, PTPL1 and Bax protein expression in lesion tissue of DLBCL group were significantly lower than those of control group whereas PDE4B, c-myc, AURKA, AURKB, PLK1, Ets-1, β-catenin, MMP7, MMP9 and CD44 protein expression were significantly higher than those of control group;PTEN, PTPL1 and Bax protein expression in DLBCL lesions were positively correlated with TNFAIP3 protein expression and negatively correlated with PDE4B protein expression;c-myc, AURKA, AURKB, PLK1, Ets-1, β-catenin, MMP7, MMP9 and CD44 protein expression were negatively correlated with TNFAIP3 protein expression and positively correlated with PDE4B protein expression. Conclusion: The low expression of TNFAIP3 and the high expression of PDE4B in diffuse large B cell lymphoma can antagonize tumor cell apoptosis and promote tumor cell invasion.

Human Soluble TRAIL Protein Inducing Apoptosis in Osteosarcoma Cell

This study is to examine the effect of human recombinant soluble TRAIL （TNF-related apoptosis-inducing ligand） protein inducing apoptosis in MG-63 human osteosarcoma cells. The inhibitive rates of TRAIL to MG-63 cells were detected by MTT assay. The apoptosis induced by TRAIL in MG-63 human osteosarcoma cells was analyzed with FACS and TUNEL and the apoptotic bodies were observed by transmission electron microscope. MTT assay showed that the inhibitive rates of 500, 1 000, 2 000 and 4 000 ng/mL TRAIL for 24 h were 10.1%, 24.3%, 50.6% and 97.7% respectively. Flow cytometric analysis showed that after MG-63 cells were treated with 2 gg/mL TRAIL for 6 h, obvious apoptotic peak would immediately appear before diploid peak. Human soluble TRAIL protein can quickly kill MG-63 osteosarcoma cells selectively, and may have potential value for clinical treatment of osteosarcoma.

Effect of HCMV IE1 Protein on Cytokines Secretion and Apoptosis of Macrophages

Objective： To investigate the effect of human cytomegalovirus （HCMV） IE1 protein on the secretory activity and apoptosis of macrophages. Methods： The eukaryotic expression vector pEGFP-C1/IE1 was used to transfect THP-1-macrophages. 48 h after transfection, the expression and localization of GFP or GFP-IE1 was observed under fluorescent microscope. The levels of IL-1β and TNF-α in the culture media were examined by ELISA, and the mRNA expression of them was analyzed by RT-PCR. Cell undergoing apoptosis were determined by flow cytometry using the propidium iodide （PI） staining method. The data were analyzed by SPSSI3.0. Results： As observed under fluorescent microscope, the expressions of GFP-IEI and GFP by plasmid pEGFP-C1/IE1 or pEGFP-C1 in THP-1-macrophages could be found in nuclei or whole cells. Conclusion： As demonstrated by RT-PCR and ELISA, mRNA and protein expressions of IL-1β and TNF-α and promotes apoptosis in THP-1-macrophages.

Different behavior of protein B23/nucleophosmin and UBF in HeLa cells during apoptosis

The behavior of UBF (upstream binding factor) and nucleophosmin in HeLa and HeLa-Bcl-2 cells during apoptosis induced by TNF-α, emetine, and their mixture was investigated. A pronounced apoptosis was achieved only in HeLa cells treated with a mixture of the inducers. Immunoblotting analysis of UBF and nucleophosmin in samples containing different portions of cells with apoptotic nuclei was carried out. It showed that UBF was proteolytically cleaved giving a stable 76-kDa fragment. Increasing content of the fragment during apoptosis correlated with the level of cells containing apoptotic nuclei and with a decrease in the content of full-sized UBF. Determination of N- and C-terminal sequences of UBF and 76-kDa fragment allowed us not only to characterize UBF at the protein level, but also to describe the site of the apoptosis-specific proteolysis. Nucleophosmin did not undergo proteolytic cleavage during apoptosis and its content was unchanged even in a sample containing 100% of cells with apoptotic nuclei. However in cells reached terminal stages of apoptosis, the balance between mono- and oligomeric forms of nucleophosmin changed due to depletion of monomeric forms and appearance of two additional oligomeric forms with lower molecular weight.

Role of JNK activation in apoptosis:Adouble-edged sword

JNK is a key regulator of many cellular events, including programmed cell death (apoptosis). In the absence of NF- κB activation, prolonged JNK activation contributes to TNF-α induced apoptosis. JNK is also essential for UV induced apoptosis. However, recent studies reveal that JNK can suppress apoptosis in IL-3-dependent hematopoietic cells via phosphorylation of the proapoptotic Bcl-2 family protein BAD. Thus, JNK has pro- or antiapoptotic functions, depend- ing on cell type, nature of the death stimulus, duration of its activation and the activity of other signaling pathways.

Signal transduction mediated by Bid,a pro-death Bcl-2 family proteins, connects the death receptor and mitochondria apoptosis pathways

Two major apoptosis pathways have been defined in mammalian cells, the Fas/TNF-R1 death receptor pathway and the mitochondria pathway. The Bcl-2 family proteins consist of both anti-apoptosis and pro- apoptosis members that regulate apoptosis, mainly by controlling the release of cytochrome c and other mitochondrial apoptotic events. However, death signals mediated by Fas/TNF-R1 receptors can usually activate caspases directly, bypassing the need for mitochondria and escaping the regulation by Bcl-2 family proteins. Bid is a novel pro-apoptosis Bcl-2 family protein that is activated by caspase 8 in response to Fas/TNF-R1 death receptor signals. Activated Bid is translocated to mitochondria and induces cytochrome c release, which in turn activates downstream caspases. Such a connection between the two apoptosis pathways could be important for induction of apoptosis in certain types of cells and responsible for the pathogenesis of a number of human diseases.

NSC-640358 acts as RXRa ligand to promote TNFa-mediated apoptosis of cancer cell

Retinoid X receptor a （RXRα） and its N-terminally trun- cated version tRXRα play important roles in tumorige. nesis, while some RXRg ligands possess potent anti- cancer activities by targeting and modulating the tumorigenic effects of RXRo and tRXRa. Here we describe NSC-640358 （N-6）, a thiazolyl-pyrazole derived compound, acts as a selective RXRα ligand to promote TNFα-mediated apoptosis of cancer cell. N-6 binds to RXRa and inhibits the transactivation of RXRα homod- imer and RXRa/TR3 heterodimer. Using mutational analysis and computational study, we determine that Arg316 in RXRa, essential for 9-cis-retinoic acid binding and activating RXRg transactivation, is not required for antagonist effects of N-6, whereas Trp305 and Phe313 are crucial for N-6 binding to RXRα by forming extra w-w stacking interactions with N-6, indicating a distinct RXRα binding mode of N-6. N-6 inhibits TR3-stimulated transactivation of Gal4-DBD-RXRα-LBD by binding to the ligand binding pocket of RXRa-LBD, suggesting a strategy to regulate TR3 activity indirectly by using small molecules to target its interacting partner RXRα. For its physiological activities, we show that N-6 strongly inhibits tumor necrosis factor a （TNFα）-induced AKT activation and stimulates TNFa-mediated apoptosis in cancer cells in an RXRa/tRXRo dependent manner.The inhibition of TNFα-induced tRXRα/p85α complex formation by N-6 implies that N-6 targets tRXRa to inhibit TNFα-induced AKT activation and to induce cancer cell apoptosis. Together, our data illustrate a new RXRa ligand with a unique RXRα binding mode and the abilities to regulate TR3 activity indirectly and to induce TNFa-mediated cancer cell apoptosis by targeting RXRα/tRXRα.

5-Hydroxymethylfurfural protects against ER stress-induced apoptosis in GalN/TNF-α-injured L02 hepatocytes through regulating the PERK-eIF2α signaling pathway

5-Hydroxymethylfurfural(5-HMF), a water-soluble compound extracted from wine-processed Fructus corni, is a novel hepatic protectant for treating acute liver injury. The present study was designed to investigate the protective effect of 5-HMF in human L02 hepatocytes injured by D-galactosamine(Gal N) and tumor necrosis factor-α(TNF-α) in vitro and to explore the underlying mechanisms of action. Our results showed that 5-HMF caused significant increase in the viability of L02 cells injured by Gal N/TNF-α, in accordance with a dose-dependent decrease in apoptotic cell death confirmed by morphological and flow cytometric analyses. Based on immunofluorescence and Western blot assays, we found that Gal N/TNF-α induced ER stress in the cells, as indicated by the disturbance of intracellular Ca2+ concentration, the activation of protein kinase RNA(PKR)-like ER kinase(PERK), phosphorylation of eukaryotic initiation factor 2 alpha(e IF2α), and expression of ATF4 and CHOP proteins, which was reversed by 5-HMF pre-treatment in a dose-dependent manner. The anti-apoptotic effect of 5-HMF was further evidenced by balancing the expression of Bcl-2 family members. In addition, the knockdown of PERK suppressed the expression of phospho-PERK, phospho-e IF2α, ATF4, and CHOP, resulting in a significant decrease in cell apoptosis after the treatment with Gal N/TNF-α. 5-HMF could enhance the effects of PERK knockdown, protecting the cells against the Gal N/TNF-α insult. In conclusion, these findings demonstrate that 5-HMF can effectively protect Gal N/TNF-α-injured L02 hepatocytes against ER stress-induced apoptosis through the regulation of the PERKe IF2α signaling pathway, suggesting that it is a possible candidate for liver disease therapy.

TNF-α Induces Transient Resistance to Fas-Induced Apoptosis in Eosinophilic Acute Myeloid Leukemia Cells

Tumor necrosis factor α （TNF-α） has been recognized as an activator of nuclear factor kB （NF-kB）, a factor implicated in the protection of many cell types from apoptosis. We and others have presented evidence to suggest that Fas-induced apoptosis may be an important aspect of the resolution of inflammation, and that delayed resolution of inflammation may be directly associated with NF-kB-dependent resistance to Fas. Because TNF-α activates NF-kB in many cell types including inflammatory cells such as eosinophils, we examined effects of TNF-α signaling on the Fas-mediated killing of an eosinophilic cell line AML14. While agonist anti-Fas （CHII） treatment induced apoptosis in AML14 cells, no significant cell death occurred in response to TNF-α alone. Electrophoretic mobility shift assay （EMSA） revealed that TNF-α induced NF-kB transactivation in AMLI4 cells in a time- and dose-dependent fashion, and subsequent supershift assays indicated that the translocated NF-kB was the heterodimer p65 （RelA）/p50. Pre-treatment of cells with TNF-α dramatically decreased the CHll-induced cell death in a transient fashion, accompanied by suppression of activation of caspase-8 and caspase-3 activation. Inhibition of NF-kB transactivation by inhibitors, BAY 11-7085 and parthenolide, reversed the suppression of Fas-mediated apoptosis by TNF-α. Furthermore, TNF-α up-regulated X-linked inhibitor of apoptosis protein （XIAP） transiently and XIAP levels were correlated with the temporal pattern of TNF-α protection against Fas-mediated apoptosis. This finding suggested that TNF-α may contribute to the prolonged survival of inflammatory cells by suppression of Fas-mediated apoptosis, the process involved with NF-kB transactivation, anti-apoptotic XIAP up-regulation and caspase suppression. Cellular ＆ Molecular Immunology. 2007;4（1）：43-52.

Hepatitis B Virus X Protein Sensitizes Primary Mouse Hepatocytes to Ethanol-and TNF-α-Induced Apoptosis by a Caspase-3-Dependent Mechanism

It is well-documented that alcohol drinking together with hepatitis viral infection accelerates liver injury;however the underlying mechanisms remain unknown.In this paper,we demonstrated that primary hepatocytes from transgenic mice overexpressing hepatitis B virus X protein(HBX)were more susceptible to ethanol- and TNF-α- induced apoptotic killing.Compared to normal control mouse hepatocytes,ethanol and/or TNF-α treatment led to a significant increase in reactive oxygen species,mitochondrial permeability transition,cytochrome C release, caspase-3 activity,and poly(ADP-ribose)polymerase degradation in hepatocytes from HBX transgenic mice. Blocking caspase-3 activity antagonized ethanol-and TNF-α-induced apoptosis in primary hepatocytes from HBX transgenic mice.Taken together,our findings suggest that HBX sensitizes primary mouse hepatocytes to ethanol- and TNF-α-induced apoptosis by a caspase-3-dependent mechanism,which may partly explain the synergistic effects of alcohol consumption and hepatitis B virus infection on liver injury.Cellular & Molecular Immunology. 2005;2(1):40-48.

Induction of type Ⅱ alveolar epithelial cells apoptosis in mouse by lipopolysaccharide does not require TNF-α

To examine whether lipopolysaccharide (LPS)-induced apoptosis correlates with TNF-α release by type Ⅱ alveolar epithelial cells (AEC Ⅱ), whether TNF-α knockout (TNF KO) abrogates the induction of apoptosis by LPS and whether TNF-α is sufficient to induce apoptosis in this cell type Methods AEC Ⅱ were isolated from wild type mice and TNF KO mice Cells were stimulated with LPS or recombinant murine TNF-α for 24 h TNF-α in culture supernatant was determined by ELISA following LPS stimulation Apoptosis was determined by the terminal deoxynucleotidyl transferase end-labeling (TUNEL) assay after treatment with either LPS or TNF-α Results LPS induced apoptosis in wild type AEC Ⅱ in a concentration-dependent manner LPS-induced AEC Ⅱ apoptosis was accompanied by an 11-fold increase (from 0 073±0 065 ng/ml in control to 0 94±0 14 ng/ml in 50 μg/ml of LPS, P<0 01) in TNF-α release However, increasing concentrations (5 or 25 ng/ml) of recombinant murine TNF-α failed to induce AEC Ⅱ apoptosis In addition, apoptosis did occur in AEC Ⅱ isolated from TNF KO mice following LPS stimulation Conclusions This study confirms that LPS induces TNF-α release and apoptosis in murine AEC Ⅱ in vitro Exogenous TNF-α failed to induce AEC Ⅱ apoptosis, and apoptosis occurred following LPS stimulation in cells lacking the ability to produce TNF-α Taken together, these results suggest that LPS-induced AEC Ⅱ apoptosis occurs by a TNF-α-independent mechanism

TNF /TNFR1 signaling pathway and endocytoplasmic reticulum stress (ERs) mediated apoptosis are involved in ofloxacin and marbofloxacin-induced apoptosis of juvenile dog joint chondrocytes in early stage in vitro.

Quinolones (QNs) are widely used for their broad antibacterial spectrum and good antibacterial activities,desirable pharmacokinetic characteristics and few cross reactions with other therapeutic agents. However,QNs have adverse effects including chondrotoxicity in juvenile animals,so the use of QNs is contraindicated in children and adolescents. In regarding to the chondrotoxicity of QNs,numerous studies have been done. The current hypothesis suggests that QNs compete with the β1 integrin receptors residing on chondrocyte surface for extracellular Mg ions,which leads to alternation in β1 integrin expression,or function and eventually results in chondrocyte death. Stupack et al (2001)demonstrated that caspase-8 could be recruited to unligated integrins in adherent cells and further initiate apoptosis in a death receptor-independent manner. Sheng et al (2008) found that ofloxacin induced rabbit's chondrocyte apoptosis by causing disturbance of β1 integrin functions and subsequently through caspase-8-dependent mitochondrial pathway.Apoptosis could be initiated through the stimulation of death receptors and through an intrinsic pathway from mitochondria. Santangelo and Bertone (2011) and Wu et al (2011) found that TNFα could be expressed in human primary condrocytes inducing by interleukin-1beta (IL-1) or lipopolysaccharide (LPS). However,to date there have not been sufficient results to support that signaling from the death receptors was involved in QNs-induced chondrocyte apoptosis.In addition,dilated cisternae of rough endoplasmic reticulum (ER) have been noticed in QNs-induced arthropathy.ER can participate in the initiation of apoptosis. Varieties of harmful cellular stimuli could lead to ERs (ER stress). Elevated ERs results in cellular apoptosis. But whether ERs mediates apoptosis in QNs-treated chondrocytes is not clear yet.In this study,we chose two QNs agents and chondrocytes were treated with ofloxacin and marbofloxacin at final concentrations of 20 μg / mL,50 μg / mL and 100 μg / mL respectively in vitro for 2 h,8 h and 24 h. Cell survival rate,cell apoptosis rate and death receptor pathway factors TNFα (intracellular tumor necrosis factor-alpha),TNFR1 (TNF receptor-1),TRADD (TNF receptor 1 associated via death domain),FADD (Fas-associated protein with death domain),caspase-8 and ERs mediated apoptosis factors caspase-12,GADD153 (CHOP or DDIT3),GRP78 (Bip),calpain,and anti-apoptosis factors Bcl-2 (B-cell lymphoma 2),NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) gene expression levels were measured by quantitative real-time reverse transcription-polymerase chain reaction (RT-qPCR) analysis to determine the dose-response relationship. We further silenced the expression of TNFR1 successfully by transferring TNFR1-siRNA to chondrocytes to confirm whether TNFα / TNFR1 signaling pathways are involved ofloxacin and marbofloxacin-induced apoptosis. Furthermore,expression of death receptor pathway representative proteins TNFα / TNFR1 and endocytoplasmic reticulum (ER) pathway representative protein caspase-12 were confirmed using Western Blot.We have found that ofloxacin and marbofloxacin could induce apoptosis of chondrocytes in a time-and dose-dependent fashion within 24 h. mRNA of TNFα,TNFR1,TRADD,FADD and caspase-8 (caspase-8 of ofloxacin treated group were at 24 h) were highly expressed at 8 h,and GADD153,GRP78,calpain and caspase-12 at 8 h or 24 h,and antiapoptosis factors NF-κB and Bcl-2 were also raised after 2 h,all in a dose-dependent fashion. Expression of caspase-8was downregulated after silenced TNFR1. TNFα and TNFR1 proteins were expressed at 8 h and caspase-12 proteins were expressed at 24 h. In addition,ofloxacin showed a higher toxicity.Our results indicate that death receptor pathway TNF / TNFR1 and ERs mediated apoptosis factors are involved in ofloxacin and marbofloxacin-induced apoptosis of in vitro cultured juvenile dog joint chondrocytes within 24 h.

Inhibition of NF-κB by mutant IκBα enhances TNF-α-induced apoptosis in HL-60 cells by controlling bcl-x_L expression

Backgound The aim of this study was to explore whether the inhibition of nuclear factor-κB (NF-κB) activation by mutant IκBα (S32,36→A) can enhance TNF-α-induced apoptosis of leukemia cells and to investigate the possible mechanism.Methods The mutant IκBα gene was transfected into HL-60 cells by liposome-mediated techniques. G418 resistant clones stably expressing mutant IκBα were obtained by the limiting dilution method. TNF-α-induced NF-κB activation was measured by electrophoretic mobility shift assay (EMSA). The expression of bcl-x L was detected by RT-PCR and Western blot after 4 hours exposure of parental HL-60 and transfected HL-60 cells to a variety of concentrations of TNF-α. The percentage of apoptotic leukemia cells was evaluated by flow cytometry (FCM). Results Mutant IκBα protein was confirmed to exist by Western blot. The results of EMSA showed that NF-κB activation by TNF-α in HL-60 cells was induced in a dose-dependent manner, but was almost completely inhibited by mutant IκBα repressor in transfected cells. The levels of bcl-x L mRNA and protein in HL-60 cells increased after exposure to TNF-α, but changed very little in transfected HL-60 cells. The inhibition of NF-κB activation by mutant IκBα enhanced TNF-α-induced apoptosis. The cytotoxic effects of TNF-α were amplified in a time- and dose-dependent manner.Conclusions NF-κB activation plays an important role in the resistance to TNF-α-induced apoptosis. The inhibition of NF-κB by mutant IκBα could provide a new approach that may enhance the anti-leukemia effects of TNF-α or even of other cytotoxic agents.

Electroacupuncture inhibits annulus fibrosis cell apoptosis in vivo via TNF-α-TNFR1-caspase-8 and integrin β1/Akt signaling pathways

OBJECTIVE: To examine whether electroacupuncture(EA) treatment inhibited cell apoptosis of intervertebral annulus fibrosis(AF) via tumor necrosis factor-α(TNF-α)-tumor necrosis factor receptor 1(TNFR1)-caspase-8 and integrin β1/Akt signaling pathways in a rat model of cervical intervertebral disc degeneration caused by unbalanced dynamic and static forces.METHODS: Thirty-two Sprague-Dawley rats were included in this study, of which 24 rats underwent surgery to induce cervical intervertebral disc degeneration, while eight rats received EA treatment at Dazhui(GV 14). Immunohistochemical staining was used to detect TNF-α, TNFR1, and caspase-8Apoptosis of AF cells was examined with terminal deoxynucleotidyl transferase-mediated d UTP-biotin nick end labeling(TUNEL) staining. The m RNA and protein expression levels of integrin β1 andAkt were evaluated with real-time polymerase chain reaction and western blot analysis, respectively.RESULTS: Treatment with EA decreased TUNEL-positive AF cells and lowered TNF-α, TNFR1 and caspase-8 positive cells compared with control groups. EA treatment also increased integrin β1and Akt m RNA and protein levels compared with controls.CONCLUSION: Treatment with EA inhibits AF cell apoptosis through suppression of the TNF-α-TNFR1-caspase-8 signal pathway and increases the expression of integrin β1 and Akt. EA may be a good alternative therapy for treating cervical spondylosis.

楮实子对肝星状细胞增殖、凋亡及TLR4/NF-κB/TNF-α信号通路的影响

目的 探究楮实子对肝星状细胞(HSC)增殖、凋亡及Toll样受体4(TLR4)/核因子-κB(NF-κB)/肿瘤坏死因子-α(TNF-α)信号通路的影响。方法 体外培养大鼠肝星状细胞系(HSC-T6),正常培养细胞作为空白组;使用转化生长因子-β1(TGF-β1)刺激细胞24 h后,分别添加不同质量浓度(0、1、5、10 g/L)的楮实子培养细胞,依次作为对照组、低剂量组、中剂量组、高剂量组。MTT法、Annexin V-FITC/PI双染法检测楮实子对HSC-T6细胞增殖、凋亡的影响;ELISA法检测HSC-T6细胞上清液中TNF-α、白细胞介素-6(IL-6)含量;Western blotting法检测HSC-T6细胞中TLR4、NF-κB、TNF-α蛋白表达。结果 楮实子可抑制活化的HSC-T6细胞增殖,促进其凋亡,且呈质量浓度依赖性(P<0.05);楮实子可降低活化的HSC-T6细胞上清液中TNF-α、IL-6水平,下调细胞中TLR4、NF-κB、TNF-α蛋白水平,并均呈质量浓度依赖性(P<0.05)。结论 楮实子可抑制HSC-T6细胞增殖,促进HSC-T6细胞凋亡,其机制可能与抑制TLR4/NF-κB/TNF-α信号通路激活有关。

TNF-α通过miR-125a-5p/JAK2/STAT3通路参与亚急性甲状腺炎发病的机制研究

目的 探讨肿瘤坏死因子α(TNF-α)对甲状腺滤泡细胞增殖、凋亡的影响及可能机制。方法 选择50例亚急性甲状腺炎患者(观察组),其中男性23例,女性27例;年龄29~57岁,平均年龄46.02岁。50例健康体检人群(正常对照组),其中男性24例,女性26例;年龄28~56岁,平均年龄45.86岁。用质量浓度10、50、100 ng/mL TNF-α处理甲状腺滤泡上皮FRTL-5细胞。FRTL-5细胞分别转染miR-125a-5p mimcs(miR-125a-5p组)、阴性对照miR-NC(miR-NC组),无任何处理的细胞作为Contol组。四甲基偶氮唑蓝(MTT)检测细胞增殖能力,流式细胞术、TUNEL染色检测细胞凋亡,酶联免疫吸附分析(ELISA)法检测血清TNF-α、细胞上清液白细胞介素6(IL-6)含量,实时荧光定量聚合酶链式反应(qRT-PCR)检测细胞miR-125a-5p、IL-6水平,Western blot检测细胞JAK2、STAT3、p-JAK2、p-STAT3蛋白表达水平。结果观察组患者外周血TNF-α、IL-6、miR-125a-5p含量高于正常对照组,差异有显著统计学意义(t=74.390、15.140、205.400,P=0.000、0.000、0.000)。TNF-α处理后的细胞的光密度(OD)值降低、凋亡率升高,miR-125a-5p、IL-6水平升高,呈浓度依赖性。与miR-NC组比较,miR-125a-5p组细胞IL-6及miR-125a-5p水平升高,OD值降低、凋亡率升高(P <0.01)。与miR-NC组比较,miR-125a-5p组细胞p-JAK2/JAK2比值、p-STAT3/STAT3比值升高(P <0.01)。结论 TNF-α在亚急性甲状腺炎患者中高表达,过表达TNF-α可促进miR-125a-5p表达,进而激活JAK2/STAT3通路上调IL-6表达。

精索静脉曲张导致的睾丸功能障碍发病机理中TNF相关的调亡诱导配体的角色

The higher frequency of varicocele in men with infertility has drawn attention and resulted in increased research at the molecular level towards treatments. The aim of this study was to investigate the role of tumor necrosis factor （TNF）-related apoptosis-inducing ligand （TRAIL） and its receptors in varicocele-induced testicular dysfunction in an experimental rat model. The rats were divided into three groups： control, sham and varicocele. Varicoceles in rats were induced by partial ligation of the left renal vein and left testes. The rats were analyzed 13 weeks after surgery. The degree of DNA fragmentation within cells in the testis was determined using terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling （TUNEL） assay. Tubule degeneration was evaluated using the Johnsen score. The expression of TRAIL and its receptors was detected by immunohistochemical and Western blotting techniques. The apoptotic index, Johnsen score and the expression of TRAIL and TRAIL receptors were examined. The data are presented as the mean-.＋s.d, and were analyzed using computer software. The KruskaI-Wallis and Dunn＇s multiple comparison tests were used in the statistical analyses. The germ cell apoptotic index was increased in rats with varicoceles when compared with the sham and control groups （P=0.0031）. The Johnsen score was significantly decreased in the varicocele group when compared with the sham and control groups （P〈O.O001）. Immunohistochemical and Western blotting analyses showed that after varicocele induction, the expression of TRAIL-R1 and TRAIL-R4 in germ cells was increased and the expression of TRAIL-R2 was decreased. There are no significant differences among the groups in terms of TRAIL and TRAIL-R3 receptor expression. The results of this study indicate that TRAIL and its receptors may have a potential role in the pathogenesis of varicocele-induced testicular dysfunction.