Homer1a reduces inflammatory response after retinal ischemia/reperfusion injury

Elevated intraocular pressure(IOP)is one of the causes of retinal ischemia/reperfusion injury,which results in NRP3 inflammasome activation and leads to visual damage.Homerla is repo rted to play a protective role in neuroinflammation in the cerebrum.However,the effects of Homerla on NLRP3inflammasomes in retinal ischemia/reperfusion injury caused by elevated IOP remain unknown.In our study,animal models we re constructed using C57BL/6J and Homer1^(flox/-)/Homerla^(+/-)/Nestin-Cre^(+/-)mice with elevated IOP-induced retinal ischemia/repe rfusion injury.For in vitro expe riments,the oxygen-glucose deprivation/repe rfusion injury model was constructed with M uller cells.We found that Homerla ove rexpression amelio rated the decreases in retinal thickness and Muller cell viability after ischemia/reperfusion injury.Furthermore,Homerla knockdown promoted NF-κB P65^(Ser536)activation via caspase-8,NF-κB P65 nuclear translocation,NLRP3 inflammasome formation,and the production and processing of interleukin-1βand inte rleukin-18.The opposite results we re observed with Homerla ove rexpression.Finally,the combined administration of Homerla protein and JSH-23 significantly inhibited the reduction in retinal thickness in Homer1^(flox/-)Homer1a^(+/-)/Nestin-Cre^(+/-)mice and apoptosis in M uller cells after ischemia/reperfusion injury.Taken together,these studies demonstrate that Homer1a exerts protective effects on retinal tissue and M uller cells via the caspase-8/NF-KB P65/NLRP3 pathway after I/R injury.

Secoemestrin C Ameliorates Psoriasis-like Skin Inflammation in Mice by Suppressing the TNF-α/NF-κB Signaling Pathway

Objective Secoemestrin C(SC),an epitetrathiodioxopiperazine isolated from Aspergillus nidulans,has been previously reported to have immunomodulatory and hepatoprotective effects against acute autoimmune hepatitis.However,the effect of SC on regulating the inflammation and its underlying mechanisms in the pathogenesis of psoriasis remain unclear.This study aimed to evaluate the effects of SC on inflammatory dermatosis both in vitro and in vivo.Methods In vitro,HaCaT cells were induced with tumor necrosis factor-alpha(TNF-α,10 ng/mL)to establish an inflammatory injury model,and the expression of nuclear transcription factor-κB(NF-κB)pathway components was measured using qRT-PCR and Western blotting.An in vivo mouse model of imiquimod(IMQ)-induced psoriasis-like skin inflammation was used to evaluate the effectiveness of SC in alleviating psoriasis.Results SC significantly blocked the activation of NF-κB signaling in TNF-α-stimulated HaCaT cells.In addition,systemic and local administration of SC improved psoriatic dermatitis in the IMQ-induced mouse model.SC reduced skin scale and significantly inhibited the secretion of inflammatory factors in skin lesions.Conclusion The protective effect of SC against psoriatic-associated inflammation reveals its potential therapeutic value for treating psoriasis.

Expression of nuclear factor-KB in hepatocellular carcinoma and its relation with the X protein of hepatitis B virus

AIM In this study we investigated the relationship of the X protein of HBV and nuclear factor-κB(NF-κB)and the expression of NF-κB in human hepatocellular carcinoma tissues. METHODS Immunohistochemistry SP method was used to detect the expression of NF-κB and the X protein of HBV in human hepatocellular carcinoma tissues of 52 cases.Gene transfection mediated by lipofectamine was used to transfect the eukaryotic expression vector pCDNA3.1-HBX of HBV x gene into human hepatocellular carcinoma cell line HCC-9204 and NF-κB was detected. RESULTS NF-κB was widely expressed in human hepatocellular carcinoma tissues in a total of 52 cases and its expression was related to the X protein of HBV.NF-κB was localized both in the cytoplasm and the nuclei of hepatocellular carcinoma cells in 11 cases which were positive for the X protein of HBV while in 41 cases negative for the X protein of HBV,NF-κB was only localized in the cytoplasm of hepatocellular carcinoma cells but translocated to the nuclei of hepatocellular carcinoma cells after the eukaryotic expression vector pCDNA3.1-HBX was transfected into HCC-9204 cells. CONCLUSION This study strongly suggests that the nuclear factor NF-κB is widely expressed in hepatocellular carcinoma tissues in different styles according to the expression of the X protein of HBV.NF-κB is abnormally activated in hepatocellular carcinoma,which is probably rélated to the X protein of HBV.The X protein of HBV can activate NF-κB to translocate into nuclei of hepatocellular carcinoma cells.

死亡结构域沉默子和p65在儿童急性淋巴细胞白血病中的表达及与化疗的关系

目的探讨凋亡调控基因死亡结构域沉默子(SODD)在儿童急性淋巴细胞白血病(ALL)中的表达、临床意义及与磷酸化-NF-κB-p65表达的相关性,研究ALL2种常用化疗药物对SODD表达的影响,试图寻找化疗新靶点。方法免疫组织化学SABC法检测25例儿童ALL骨髓细胞SODD、p65蛋白表达水平;长春新碱(VCR)处理Jurkat细胞后,Annexin-V-Fluorescence/PI双标记的流式细胞术检测细胞凋亡发生率,免疫印迹法检测SODD及p65在化疗药物作用下的表达变化。结果25例ALL中,SODD和p65表达的阳性率较健康对照组高,其中高危病例组SODD阳性表达率较标危病例组阳性表达率高,有显著性差异(Pa<0.05),且骨髓细胞中SODD与p65表达呈正相关(r=0.69P<0.01);VCR能有效诱导Jurkat细胞凋亡,在该凋亡过程中,SODD及p65表达下调,并呈时间依赖性,但柔红霉素(DNR)不能有效下调SODD的表达。结论SODD和p65均参与了ALL的发生发展,且存在一定的协同关系,SODD与ALL临床分型及预后有密切关系;VCR特异下调白血病细胞中SODD的表达及抑制NF-κB的活化,恢复白血病细胞的凋亡敏感性。

Inhibitory effects of saikosaponin-d on CCl_4-induced hepatic fibrogenesis in rats

AIM： To investigate the suppressive effect of saikosaponin-d （SSd） on hepatic fibrosis in rats induced by CCh injections in combination with alcohol and high fat, low protein feeding and its relationship with the expression of nuclear factor-κB （NF-κB）, tumor necrosis factor-alpha （TNF-α） and interleukins-6 （IL-6）. METHODS： Hepatic fibrosis models were induced by subcutaneous injection of CCh at a dosage of 3 mL/kg in rats. At the same time, rats in treatment groups were injected intraperitoneally with SSd at different doses （1.0, 1.5 and 2.0 mg/kg） once daily for 6 wk in combination with CCh, while the control group received olive oil instead of CCh. At the end of the experiment, rats were anesthetized and killed （except for 8 rats which died during the experiment; 2 from the model group, 3 in high-dose group, 1 in medium-dose group and 2 in lowdose group）. Hernatoxylin and eosin （HE） staining and Van Gieson staining were used to examine the changes in liver pathology. The levels of alanine aminotransferase （ALT）, triglyeride （TG）, albumin （ALB）, globulin （GLB）, hyaluronic acid （HA） and larninin （LN） in serum and the content of hydroxyproline （HYP） in liver were measured by biochemical examinations and radioimmuneoassay, respectively. In addition, the expression of TNF-α and IL-6 in liver homogenate was evaluated by enzymelinked immunosorbent assay （ELISA） and the levels of NF-κBp65 and I-κBa in liver tissue were analyzed by Western blotting. RESULTS： Both histological examination and Van Gieson staining demonstrated that SSd could attenuate the area and extent of necrosis and reduce the scores of liver fibrosis. Similarly, the levels of ALT, TG, GLB, HA, and LN in serum, and the contents of HYP, TNF-α and IL-6 in liver were all significantly increased in model group in comparison with those in control group. Whereas, the treatment with SScl markedly reduced all the above parameters compared with the model group, especially in the medium group （ALT： 412 ± 94.5 IU/L vs 113.76 ± 14.91 IU/L, TG： 0.95 ± 0.16 mmol/L vs 0.51 ± 0.06 mmol/L, GLB： 35.62 ± 3.28 g/L vs 24.82 ± 2.73 g/L, HA： 42.15 ± 8.25 ng/mL vs 19.83 ± 3.12 ng/mL, LN： 27.56 ± 4.21 ng/mL vs 13.78 ± 2.57 ng/mL, HYP： 27.32 ± 4.32 ug/mg vs 16.20 ± 3.12 ug/mg, TNF-a： 4.38 ± 0.76 ng/L vs 1.94 ± 0.27 ng/L, IL-6：28.24 ± 6.37 pg/g vs 12.72 ± 5.26 pg/g, respectively, P 〈 0.01）. SSd also decreased ALB in serum （28.49 ± 4.93 g/L vs 37.51 ± 3.17 g/L, P 〈 0.05）. Moreover, the expression of NF-KB p65 in the liver of treated groups was lower than that in model groups while the expression of I-κBa was higher in treated group than in model group （P 〈 0.01）. The expression of NF-κBp65 and TNF-a had a positive correlation with the level of HA in serum of rats after treatment with CCh （r = 0.862, P 〈 0.01; r = 0.928, P 〈 0.01, respectively）. CONCLUSION： SSd attenuates CCh-induced hepatic fibrosis in rats, which may be related to its effects of hepato-protective and anti-inflammation properties, the down-regulation of liver TNF-a, IL-6 and NF-κBp65 expression and the increased I-κBa activity in liver.

Effects of β-Aescin on the expression of nuclear factor-κB and tumor necrosis factor-α after traumatic brain injury in rats

To investigate the inhibiting effect of β-Aescin on nuclear factor-κB (NF-κB) activation and the expression of tumor necrosis factor-α (TNF-α) protein after traumatic brain injury (TBI) in the rat brain, 62 SD rats were subjected to lateral cortical impact injury caused by a free-falling object and divided randomly into four groups: (1) sham operated (Group A); (2) injured (Group B); (3) β-Aescin treatment (Group C); (4) pyrrolidine dithocarbamate (PDTC) treatment (Group D). β-Aescin was administered in Group C and PDTC treated in Group D immediately after injury. A series of brain samples were obtained directly 6h, 24 h and 3 d respectively after trauma in four groups. NF-κB activation was examined by Electrophoretic Mobility Shift Assay (EMSA); the levels of TNF-α protein were measured by radio-immunoassay (RIA); the water content of rat brain was measured and pathomorphological observation was carried out. NF-κB activation, the levels of TNF-α protein and the water content of rat brain were significantly increased (P＜0.01) following TBI in rats. Compared with Group B, NF-κB activation (P＜0.01), the levels of TNF-α protein (P＜0.01) and the water content of brain (P＜0.05) began to decrease obviously after injury in Groups C and D.β-Aescin could dramatically inhibit NF-κB activation and the expression of TNF-α protein in the rat brain, alleviate rat brain edema, and that could partially be the molecular mechanism by which β-Aescin attenuates traumatic brain edema.

Hyperbaric Oxygen Treatment Improves Hearing Level via Attenuating TLR4/NF-κB Mediated Inflammation in Sudden Sensorineural Hearing Loss Patients

Objective Hyperbaric oxygen treatment(HBOT)has demonstrated efficacy in improving hearing levels of patients with idiopathic sudden sensorineural hearing loss(ISSHL);however,the underlying mechanisms are not well understood.HBOT alleviates the inflammatory response,which is mediated by Toll-like receptor(TLR)4 and nuclear factor(NF)-κB.In this study we investigated whether HBOT attenuates inflammation in ISHHL patients via alteration of TLR4 and NF-κB expression.Methods ISHHL patients(n=120)and healthy control subjects(n=20)were enrolled in this study.Patients were randomly divided into medicine group treated with medicine only(n=60)and HBO group receiving both HBOT and medicine(n=60).Audiometric testing was performed pre-and posttreatment.TLR4,NF-кB,and TNF-αexpression in peripheral blood of ISSHL patients and healthy control subjects was assessed by ELISA before and after treatment.Results TLR4,NF-κB,and TNF-αlevels were upregulated in ISSHL patients relative to healthy control subjects;the levels were decreased following treatment and were lower in the HBO group than that in the medicine group post-treatment(P<0.05 and P<0.01).Conclusion HBOT alleviates hearing loss in ISSHL patients by suppressing the inflammatory response induced by TLR4 and NF-κB signaling.

Oxymatrine reduces neuroinflammation in rat brain A signaling pathway

Cerebral neuroinflammation models were established by injecting 10μg lipopolysaccharide into the hippocampus of male Sprague-Dawley rats. The rats were treated with an intraperitoneal injection of 120, 90, or 60 mg/kg oxymatrine daily for three days prior to the lipopolysaccharide injection. Twenty-four hours after model induction, the hippocampus was analyzed by real-time quantitative PCR, and the cerebral cortex was analyzed by enzyme-linked immunosorbent assay and western blot assay. The results of the enzyme-linked immunosorbent assay and the real-time quantitative PCR showed that the secretion and mRNA expression of the pro-inflammatory cytokines interleukin-113 and tumor necrosis factor-a were significantly decreased in the hippocampus and cerebral cortex of model rats treated with oxymatrine. Western blot assay and real-time quantitative PCR analysis indicated that toll-like receptor 4 mRNA and protein expression were significantly decreased in the groups receiving different doses of oxymatrine. Additionally, 120 and 90 mg/kg oxymatrine were shown to reduce protein levels of nuclear factor-KB p65 in the nucleus and of phosphorylated IKBa in the cytoplasm of brain cells, as detected by western blot assay. Experimental findings indicate that oxymatrine may inhibit neuroinflammation in rat brain via downregulating the expression of molecules in the toll-like receptor 4/nuclear factor-KB signaling Dathwav.

Naoxintong dose effects on inflammatory factor expression in the rat brain following focal cerebral ischemia

BACKGROUND： Certain components of tetramethylpyrazine, a traditional Chinese medicine, exhibit protective effects against brain injury. OBJECTIVE： To investigate the effects of different Naoxintong doses on expression of nuclear factor-kappa B （ kB）, interleukin-6, tumor necrosis factor-α, and complement 3 in rats following focal cerebral ischemia. DESIGN, TIME AND SETTING： The randomized experiment was performed at the Laboratory of Neurology, Second Hospital of Hebei Medical University from June 2004 to June 2006. MATERIALS： A total of 150 adult, healthy, male, Sprague Dawley rats, weighing 280-320g, were selected. Naoxintong powder （mainly comprising szechwan lovage rhizome, milkvetch root, danshen root, and radix angelicae sinensis） was obtained from Buchang Pharmacy Co., Ltd. in Xianyang City of Shanxi Province of China, lot number 040608. METHODS： The rats were randomly assigned into sham operation, saline, high-dose Naoxintong, moderate-dose Naoxintong, and low-dose Naoxintong groups, with 30 rats in each group. Rat models of middle cerebral artery occlusion were established using the suture method, with the exception of the sham operation group. Rats in the high-dose, moderate-dose and low-dose Naoxintong groups received 4, 2, and 1 g/kg Naoxintong respectively, by gavage. Rats in the saline group were treated with 1 mL saline by gavage All rats were administered by gavage at 5 and 23 hours following surgery, and subsequently, once per day. MAIN OUTCOME MEASURES： At 6, 24, 48, 72 hours, and 7 days following model establishment, brain water content was measured. Histopathological changes in brain tissues were detected using hematoxylin-eosin staining. Expression of nuclear factor- kB, interleukin-6, tumor necrosis factor- α, and complement 3 was examined by immunohistochemistry. RESULTS： A total of 150 rats were included in the final analysis with no loss. Brain water content was significantly increased in the ischemic hemisphere of rats from the saline, as well as the high-dose, moderate-dose, and low-dose Naoxintong groups at 24 hours, which reached a peak at 48 hours. At 6, 24, 48, 72 hours, and 7 days, brain water content was greater in the ischemic hemisphere of rats from the saline, as well as the high-dose, moderate-dose, and low-dose Naoxintong groups, compared with the sham operation group （P 〈 0.05）. At 24 and 48 hours, brain water content was reduced in the high-dose and moderate-dose Naoxintong groups, compared to the saline and low-dose Naoxintong groups （P 〈 0.05）. In the saline, as well as high-dose, moderate-dose, and low-dose Naoxintong groups, neuronal edema was observed at 6 hours surrounding the ischemic sites. Inflammatory cells appeared at 24 hours, reached a peak at 48 hours, and gradually diminished. A small amount of glial cell proliferation and neuronal degeneration were observed in the hippocampus at 72 hours following infarction. Microglial proliferation and aggregation were detected at 7 days after infarction. Expression of nuclear factor- kB, interleukin-6, tumor necrosis factor-α, and complement 3 was significantly less in the high-dose, moderate-dose, and low-dose Naoxintong groups, compared to the sham operation group （P 〈 0.05）. Expression of the above-mentioned inflammatory cytokines was lower in rat brain tissues of the high-dose Naoxintong group, compared to the low-dose Naoxintong group （P 〈 0.05）. CONCLUSION： High-dose Naoxintong and moderate-dose Naoxintong significantly alleviated rat brain edema and decreased expression of nuclear factor-kB, interleukin-6, tumor necrosis factor-α, and complement 3 in brain tissues. The protective effect of high-dose Naoxintong was most significant.

(Z)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione protects rats from carbon tetrachloride-induced liver injury and fibrogenesis

AIM： To evaluate the hepatoprotective roles of （Z）- 5-（4-methoxybenzylidene）thiazolidine-2,4-dione （SKLB010） against carbon tetrachloride （CCI4）-induced acute and chronic liver injury and its underlying mecha- nisms of action.

Zinc-deficient diet aggravates ventilation-induced lung injury in rats

We investigated the effects of zinc deficiency on acute lung injury （ALI） induced by mechanical ventilation. Male Sprague-Dawley rats were fed with a zinc-deficient or zinc-proficient diet for 4 weeks, and then received mechanical ventilation at normal frequency and pressure for 30 min. Total protein, cell count, the number of poly- morphonuclear neutrophil （PMN） in the bronchoalveolar lavage （BAL）, and vascular endothelial growth factor （VEGF） expression in the lung were determined. Activation of nuclear factor-t^B （NF-~cB） was detected by exam- ining the phosphorylation of NF-kB （pNF-kB p65） and the expression of inhibitor of NF-kB （pI-kBa）. Compared to the controls, total cell count and the number of PMNs were significantly increased to 160% and 140%, respec- tively, in zinc-deficient rats treated with ventilation. Activation of NF-kB was significantly increased and VEGF was also increased to three-folds. Zinc deficiency aggravated the inflammatory response in rats and was associated with the overexpression of VEGF in response to mechanical ventilation. Zinc supplementation may be beneficial to zinc-deficient patients during mechanical ventilation.

The clinical significance of CD97, NF-kB and COX-2 ingastric MALT lymphomas

Background and Objectives: Increased expression of the CD97, nuclear factor-kB (NF-kB) and cyclooxygenase-2 (COX-2) has been found to play an important role in development of many cancers, including gastric neoplasm. However, the expression and biological behavior of CD97, NF-kB and COX-2 in gastric MALT (mucosa-associated lymphoid tissue) lymphoma has not been well investigated. Methods: The expressions of CD97, COX-2 and NF-kB in 47 cases of gastric MALT lymphoma were detected immunohistochemically, and the relevance between their expressions and the biological behavior was analyzed retrospectively. Results: 1) The expressions of CD97, NF-kB and COX-2 were 87.2%, 36.2% and 48.9%, respectively;2) The difference of CD97 expression between depth of invasion limited in mucosa and submucosa and beyond muscularis propria was significant (100.0% vs. 71.4%, P < 0.01). Moreover, the expression of nuclear CD97 between stage IIE, III, IV and stage I patients showed significant difference (96.4% vs. 73.7%, P < 0.05);3) The expression of NF-kB was significantly correlated with tumor size, depth of invasion and stage;4) The expression of COX-2 was significantly correlated with Helicobacter pylori infection, clinical stage, depth of invasion and tumor size (P < 0.05). Conclusions: Expressions of CD97, NF-κB and COX-2 were correlated with tumor invasion and metastasis in gastric MALT lymphoma.

PI3-K/PKB/NF-κB and p42/44 MAPK pathway mediates inhibition of lipoxin A_4 on CTGF-induced production of RANTES in mesangial cells

In order to investigate the regulatory role of connective tissue growth factor （CTGF） on production of RANTES （regulated on activation, normal T cell expressed and secreted） in rat glomerular mesangial cells, and the modulatory effect of lipoxin A4 （ LXA4 ） on action of CTGF, and to explore the mechanisms of action of CTGF and LXA4, cultured rat mesangial cells were treated with CTGF, with or without preincubation with LXA4. Expression of mRNA was analyzed by RT-PCR. Protein of RANTES in the supematants was determined by ELISA. Monocyte transmigration was assessed by in vitro chemotaxis assay. Expression of p42/44 mitogen-activated protein kinase （MAPK）, phosphoinositide 3-kinase （ PI3- K） and protein kinase B （PKB） was assessed by Western blotting. DNA-binding activity of nuclear factor-roB （NF-kB） was determined by electrophoretic mobility shift assay （EMSA）. To observe whether transfection of LXA4 receptor homologue gene （LRHg） into mesangial cells intensified these modulatory effects of LXA4, mesangial cells were transfected with pcDNA3.1/LRHG vector. The results showed that CTGF enhanced the mRNA expression and protein release of RANTES, and the expression of phospho （P）-p42/44 MAPK, P-PI3-K, P-PKB and NF-kB. P-p42/44 MAPK blockade inhibited the CTgF-induced expression of P-p42/44 MAPK and partially decreased the level of RANTES in supematants. P- PI3-K blockade downregulated the CTGF-stimulated expression of P-PI3-K, P-PKB and NF-kB, and partially decreased the release of RANTES. NF-kB blockade abrogated the CTGF-activated NF-kB and partially decreased the secretion of RANTES. LXA4 dose-dependently inhibited the CTGF-stimulated above action. Transfection of LRHG into mesangial cells intensified these inhibitory effects of LXA4 on CTGFinduced release of RANTES and expression of the P-p42/44 MAPK. In conclusion, LXA4 inhibits CTGFinduced production of RANTES via PI3-K/PKB/NF-kB and p42/44 MAPK-dependent signal pathway, which is mediated by LRHG in rat mesangial cells.

Requirement for endogenous heat shock factor 1 in inducible nitric oxide synthase induction in murine microglia

Aim Inducible nitric oxide synthase （iNOS） makes a great contribution to host defense and inflamma-tion. In many settings, lipopolysaccharide （LPS） induces iNOS expression through activation of the inhibitor of KB- α （IKB-α） -nuclear factor-KB （NF-KB） cascade, whereas interferon-γ （IFN-γ） acts through Janus kinase （ JAK）- signal transducer and activator of transcription 1 （ STAT1 ） signals. Heat shock factor 1 （ HSF1 ）, a major regulator of heat shock protein transcription, has been shown to regulate the production of pro-inflammatory cytokines such as tumor necrosis factor-α（TNF-α） and interleukin-6 （IL-6）. But it remains obscure whether and how HSF1 affects iNOS induction. Methods Western blot was used to measure the protein expression. The mRNA level was meas- ured by real time-PCR. Silence of HSF1 was achieved by small interfering RNA. Nitric oxide （NO） content and NF-KB binding activity were assayed by commercial kits. Chromatin immunoprecipitation （CHIP） was used to measure the binding activity of NF-KB and STAT1 to iNOS promoters. Results HSF1 inhibition or knockdown pre- vented the LPS- and/or IFN-γ-stimulated iNOS protein expression in cultured microglia. HSF1 inhibition blocked iNOS mRNA transcription. These inhibitory effects of HSF1 inhibition on iNOS expression were confirmed in brain tissues from endotoxemic mice. Further analysis showed that HSF1 inhibition had no effect on IKB-α degradation and NF-KB or STAT1 phosphorylation in LPS/IFN-γ-stimulated cells. The nuclear transport of active NF-KB or STAT1 was also not affected by HSF1 inhibition. But HSF1 inhibition reduced the binding of NF-KB and STAT1 to their DNA elements. In addition, HSF1 inhibition reduced NF-KB and STAT1 bindings to iNOS promoter inside the LPS/IFN-γ-stimulated cells. Conclusions This preventing effect of HSF1 inhibition on iNOS mRNA transcription presents the necessary role of HSF1 in iNOS induction.

The Protective Role of Succinic Acid on the NF kB Signaling Pathway of Mouse Fibroblast Cells under the Influence of Chromium Oxide and Sodium Arsenite

Antioxidant and anti-inflammatory therapy approaches have been in the focus of attention in the treatment of different cancer diseases where oxidative stress has been implicated. Succinic acid has been previously reported to possess radical scavenger, iron chelating and anti-inflammatory properties in the mouse fibroblast. The purpose of this study was to investigate potential therapeutic effects of succinic acid and possible signal pathway involved in the mouse fibroblast. We demonstrated highly potent antioxidant-radical scavenging activities of succinic acid.

磷酸化核转录因子-κB在骨癌痛大鼠脊髓背角的表达变化

目的观察骨癌痛大鼠脊髓水平磷酸化核转录因子-κB（phospho-nuclear factor—κB，p-NF-κB）的表达位置及表达变化。方法雌性未交配Sprague-Dawley（SD）大鼠48只，体重160g-200g，采用随机数字表法将其随机分为两组：假手术组（S组）、骨癌痛（bonecan cerpain，BCP）组（BP组），每组24只。选用von Frey纤维丝检测各组大鼠造模前及造模后3、7、14、21d机械缩足阈值（mechanical withdrawal threshold，MWT），评价疼痛行为学变化。采用免疫荧光法检测S组和BP组术前1d及术后7、14、21d大鼠脊髓L4-6节段背角Ⅰ、Ⅱ板层p-NF-κB阳性细胞数的变化。免疫荧光双标法检测脊髓L4-6节段背角Ⅰ、Ⅱ板层p-NF-κB与神经元标志物神经元特异核蛋白（neuronal nuclei，NeuN）、小胶质细胞标志物离子钙接头蛋白分子-1（ionized calcium bindingad aptormolecule-1，Iba-1）、星形胶质细胞标志物胶质纤维酸性蛋白（glia fibrillary acidic protein，GFAP）共表达情况。结果各组肿瘤细胞接种前MWT比较差异无统计学意义（P〉0．05）；与S组比较，BP组肿瘤细胞接种后第7天MWT[（3．57±1．29）g]、第14天MWT[（1．66±0．39）g]、第21天MWT[（1．40±0．16）g]降低（P〈0．05）；S组各时间点MWT差异无统计学意义（P〉0．05）。与S组比较，BP组大鼠术后7d脊髓L4-6节段背角Ⅰ、Ⅱ板层p-NF-κB表达水平升高，随时间延长逐渐升高（P〈0．05）。p-NF-κB几乎都与GFAP共表达，而很少与NeuN、Iba-1共表达。结论BCP大鼠脊髓背角水平星形胶质细胞内p-NF-κB参与介导BCP大鼠机械痛敏。

Mannan-binding lectin directly interacts with Toll-like receptor 4 and suppresses lipopolysaccharide-induced inflammatory cytokine secretion from THP-1 cells

Mannan-binding lectin(MBL)plays a key role in the lectin pathway of complement activation and can influence cytokine expression.Toll-like receptor 4(TLR4)is expressed extensively and has been demonstrated to be involved in lipopolysaccharide(LPS)-induced signaling.We first sought to determine whether MBL exposure could modulate LPS-induced inflammatory cytokine secretion and nuclear factor-kB(NF-kB)activity by using the monocytoid cell line THP-1.We then investigated the possible mechanisms underlying any observed regulatory effect.Using ELISA and reverse transcriptase polymerase chain reaction(RT-PCR)analysis,we found that at both the protein andmRNAlevels,treatment withMBLsuppresses LPS-induced tumor-necrosis factor(TNF)-a and IL-12 production in THP-1 cells.An electrophoretic mobility shift assay and western blot analysis revealed that MBL treatment can inhibit LPS-induced NF-kB DNA binding and translocation in THP-1 cells.While the binding of MBL to THP-1 cells was evident at physiological calcium concentrations,this binding occurred optimally in response to supraphysiological calcium concentrations.This binding can be partly inhibited by treatment with either a soluble form of recombinant TLR4 extracellular domain or anti-TLR4 monoclonal antibody(HTA125).Activation of THP-1 cells by LPS treatment resulted in increased MBL binding.We also observed that MBL could directly bind to the extracellular domain of TLR4 in a dose-dependent manner,and this interaction could attenuate the binding of LPS to cell surfaces.Taken together,these data suggest that MBL may affect cytokine expression through modulation of LPS-/TLR-signaling pathways.These findings suggest that MBL may play an important role in both immune regulation and the signaling pathways involved in cytokine networks.

The regulating role of mutant IKBα in expression of TIMP-2 and MMP-9 in human glioblastoma multiform

Background Our previous studies demonstrated that mutant IKBα （IKBαM） inhibited the occurrence, growth and angiogenesis of human glioblastoma multiform （GBM）. However, the specific mechanism by which IKBaM regulates protein-degrading enzymes secreted from GBM to inhibit invasion and metastasis has remained unclear. The aim of the present study was to investigate the regulatory role and significance of IKBαM genes in the expression of tissue inhibitor of metalloproteinase （TIMP）-2 and matrix metalloproteinase （MMP）-9 in human GBM. Methods We established the following four GBM cell lines stably expressing IKBaM by plasmid construction, gene transfection and screening for IKBαM protein expression： mutant IKBa-transfected cells （G36A-M）, wild-type IKBa-transfected cells （G36A-W）, empty plasmid transfected cells （G36A-P） and untransfected cells （G36A）. The TIMP-2 and MMP-9 expression was detected by RT-PCR and Western blotting. Tumor cells were then implanted subcutaneously into nude mice to establish an animal model of ectopic tumor growth, and TIMP-2 and MMP-9 expression was determined by immunohistochemical methods. Results The results showed that there was a significant increase in TIMP-2 expression and a significant decrease in MMP-9 expression in the G36A-M group at both the RNA and protein levels compared with the G36A-W group, G36A-P group and G36A group. Similar results were observed in the immunohistochemical staining analysis of tumor tissues. In the G36A-M group, TIMP-2 expression was significantly higher while MMP-9 expression was significantly lower than in the other three groups. Conclusions Our findings indicate that IKBaM inhibits the activation of NF-KB. It significantly up-regulates TIMP-2 expression in human malignant glioma cells and down-regulates the expression of MMP-9. Thus, IKBαM maintains the integrity of the extracellular matrix and further inhibits the growth and metastasis of tumor tissues. Chin Med J 2009; 122（2）：205-211

Effects of Andrographolide on the Activation of Mitogen Activated Protein Kinases and Nuclear Factor-κ B in Mouse Peritoneal Macrophage-derived Foam Cells

Objective： To observe the effect of andrographolide on the activation of mitogen-activated protein kinases （MAPKs） and expression of nuclear factor- kB （NF-kB） in macrophage foam cells. Methods： The mouse peritoneal macrophages were cultured in the media in the presence of oxidized low-density lipoprotein （ox-LDL）, ox-LDL＋andrographolide, or neither （control）. The phosphorylation of MAPK molecules （p38MAPK, JNK, ERK1/2） and the expressions of NK- kB p65 were examined by Western blot. Results： As compared with cells in the control group, the expressions of phospho-p38 and NF- kB p65 were increased in the cells cultured with either ox-LDL or ox-LDL＋andrographolide （P〈0.01）, but attenuated significantly in the presence of ox-LDL＋ andrographolide when compared with ox-LDL （P〈0.05）. The phospho-JNK increased in the presence of either ox-LDL or ox-LDL＋andrographolide when compared with control cells （P〈0.01）, but no significant difference existed between ox-LDL and ox-LDL＋andrographolide （P〉0.05）. The expression of phospho-ERK1/2 was increased in the presence of ox-LDL compared with the control cells （P〈0.01）, but no significant differences existed between the cells cultured in the presence of ox-LDL＋andrographolide and the control medium （P〉0.05）. Conclusions： Andrographolide could inhibit the activation of ERK1/2, p38MAPK and NK-kB induced by ox-LDL in macrophage foam cells, which might be one of its mechanisms in preventing atherosclerosis.

Metformin ameliorates insulin resistance in L6 rat skeletal muscle cells through upregulation of SIRT3

Background SIRT3 is an important regulator in cell metabolism, and recent studies have shown that it may be involved in the pharmacological effects of metformin. However, the molecular mechanisms underlying this process are unclear. Methods The effects of SIRT3 on the regulation of oxidative stress and insulin resistance in skeletal muscle were evaluated in vitro. Differentiated L6 skeletal muscle cells were treated with 750 pmol/L palmitic acid to induce insulin resistance. SIRT3 was knocked down and overexpressed in L6 cells. SIRT3, nuclear factor kappa-light-chain-enhancer of activated B cells （NF-KB） p65, c-Jun N-terminal kinase 1 （JNK1）, and superoxide dismutase 2 （SOD2） were evaluated by Western blotting. Results Over expression of SIRT3 increased glucose uptake and decreased ROS production in L6-1R cells as well as in L6 cells. Knock-down of SIRT3 induced increased production of ROS while decreased glucose uptake in both L6 and L6- IR cells, and these effects were reversed by N-acetyI-L-cysteine （NAC）. Metformin increased the expression of SIRT3 （1.5- fold） and SOD2 （2-fold） while down regulating NF-KB p65 （1.5-fold） and JNK1 （1.5-fold）. Knockdown of SIRT3 （P〈0.05） reversed the metformin-induced decreases in NF-KB p65 and JNK1 and the metformin-induced increase in SOD2 （P〈0.05）. Conclusions Upregulated SIRT3 is involved in the pharmacological mechanism by which metformin promotes glucose uptake. Additionally, SIRT3 may function as an important regulator of oxidative stress and a new alternative approach for targeting insulin resistance-related diseases.