HSP110 aggravates ischemia-reperfusion injury after liver transplantation by promoting NF-κB pathway

Background:Ischemia-reperfusion injury(IRI)poses a significant challenge to liver transplantation(LT).The underlying mechanism primarily involves overactivation of the immune system.Heat shock protein 110(HSP110)functions as a molecular chaperone that helps stabilize protein structures.Methods:An IRI model was established by performing LT on Sprague-Dawley rats,and HSP110 was silenced using siRNA.Hematoxylin-eosin staining,TUNEL,immunohistochemistry,ELISA and liver enzyme analysis were performed to assess IRI following LT.Western blotting and quantitative reverse transcription-polymerase chain reaction were conducted to investigate the pertinent molecular changes.Results:Our findings revealed a significant increase in the expression of HSP110 at both the mRNA and protein levels in the rat liver following LT(P<0.05).However,when rats were injected with siRNAHSP110,IRI subsequent to LT was notably reduced(P<0.05).Additionally,the levels of liver enzymes and inflammatory chemokines in rat serum were significantly reduced(P<0.05).Silencing HSP110 with siRNA resulted in a marked decrease in M1-type polarization of Kupffer cells in the liver and downregulated the NF-κB pathway in the liver(P<0.05).Conclusions:HSP110 in the liver promotes IRI after LT in rats by activating the NF-κB pathway and inducing M1-type polarization of Kupffer cells.Targeting HSP110 to prevent IRI after LT may represent a promising new approach for the treatment of LT-associated IRI.

Calcitriol attenuates liver fibrosis through hepatitis C virus nonstructural protein 3-transactivated protein 1-mediated TGF β1/Smad3 and NF-κB signaling pathways

BACKGROUND Hepatic fibrosis is a serious condition,and the development of hepatic fibrosis can lead to a series of complications.However,the pathogenesis of hepatic fibrosis remains unclear,and effective therapy options are still lacking.Our group identified hepatitis C virus nonstructural protein 3-transactivated protein 1(NS3TP1) by suppressive subtractive hybridization and bioinformatics analysis,but its role in diseases including hepatic fibrosis remains undefined.Therefore,additional studies on the function of NS3TP1 in hepatic fibrosis are urgently needed to provide new targets for treatment.AIM To elucidate the mechanism of NS3TP1 in hepatic fibrosis and the regulatory effects of calcitriol on NS3TP1.METHODS Twenty-four male C57BL/6 mice were randomized and separated into three groups,comprising the normal,fibrosis,and calcitriol treatment groups,and liver fibrosis was modeled by carbon tetrachloride(CCl4).To evaluate the level of hepatic fibrosis in every group,serological and pathological examinations of the liver were conducted.TGF-β1 was administered to boost the in vitro cultivation of LX-2 cells.NS3TP1,α-smooth muscle actin(α-SMA),collagen I,and collagen Ⅲ in every group were examined using a Western blot and real-time quantitative polymerase chain reaction.The activity of the transforming growth factor beta 1(TGFβ1)/Smad3 and NF-κB signaling pathways in each group of cells transfected with pcDNA-NS3TP1 or siRNA-NS3TP1 was detected.The statistical analysis of the data was performed using the Student’s t test.RESULTS NS3TP1 promoted the activation,proliferation,and differentiation of hepatic stellate cells(HSCs)and enhanced hepatic fibrosis via the TGFβ1/Smad3 and NF-κB signaling pathways,as evidenced by the presence of α-SMA,collagen I,collagen Ⅲ,p-smad3,and p-p65 in LX-2 cells,which were upregulated after NS3TP1 overexpression and downregulated after NS3TP1 interference.The proliferation of HSCs was lowered after NS3TP1 interference and elevated after NS3TP1 overexpression,as shown by the luciferase assay.NS3TP1 inhibited the apoptosis of HSCs.Moreover,both Smad3 and p65 could bind to NS3TP1,and p65 increased the promoter activity of NS3TP1,while NS3TP1 increased the promoter activity of TGFβ1 receptor I,as indicated by coimmunoprecipitation and luciferase assay results.Both in vivo and in vitro,treatment with calcitriol dramatically reduced the expression of NS3TP1.Calcitriol therapy-controlled HSCs activation,proliferation,and differentiation and substantially suppressed CCl4-induced hepatic fibrosis in mice.Furthermore,calcitriol modulated the activities of the above signaling pathways via downregulation of NS3TP1.CONCLUSION Our results suggest that calcitriol may be employed as an adjuvant therapy for hepatic fibrosis and that NS3TP1 is a unique,prospective therapeutic target in hepatic fibrosis.

Donkey whey proteins ameliorate dextran sulfate sodium-induced ulcerative colitis in mice by downregulating the S100A8-TRAF6-NF-κB axis-mediated inflammatory response

Donkey milk has a variety of physiological functions, including antibacterial and anti-inflammatory. Donkey whey proteins(DWPs), as the main functional component in donkey milk, its inhibitory effect on colitis is still unclear. In this study, the inhibitory effect and potential mechanism of DWPs on dextran sulfate sodium(DSS)-induced colitis were investigated. Firstly, the DWPs and bovine milk whey proteins(BWPs)were characterized using proteomics. Then, we administered DWPs and BWPs to mice with colitis via oral gavage. The results of immunohistochemistry and flow cytometry indicated that DWPs increased T regulatory cell accumulation and increased the abundance of the cluster of differentiation 205+(CD205+)macrophages compared to those with BWPs and in model groups. In addition, DWPs exhibited a more remarkable ability to inhibit pro-inflammatory proteins(S100A8, TRAF6, and NF-κB)expression and inflammatory secretion than BWPs. In addition, DWPs significantly decreased NF-κB and CD86 levels more than BWPs or the negative control in both LPS-stimulated human peripheral blood mononuclear cells or cell lines. These findings indicate that DWPs comprise a promising anti-colitis functional food, and this work has established a foundation for future research on these compounds.

Effects of Echinacea Polysaccharide on Expression of NF-κB Protein Secreted by LPS-injured IEC-6 Cells

[ Objective ] The paper was to explore effects of Echinacea polysaccharide （EPS） on expression of NF-KB protein secreted by LPS-injured IEC-6 cells, and to provide a theoretical basis for clinical application of Echinacea purpurea against bacterial diseases and enhancement of immunity. [ Method] Nucleoprotein extracted from IEC-6 cells in normal control group, LPS group, different concentrations of EPS （50, 100,200,500 μg/mL） ＋ LPS groups were detected by SDS- PAGE electrophoresis, and the content of NF-κB protein was analyzed using western blotting method. [ Result ] The content of NF-KB protein in normal control group was the lowest, while that in LPS group was the highest. The content of NF-κB protein in EPS group gradually decreased with the increasing concentration of EPS. [ Result] The expression of NF-κB protein increased when IEC-6 cells were stimulated by LPS, and EPS could effectively inhibit increased expression of NF- κB protein. With the increasing concentration of EPS, the inhibition effect against increased expression of NF-κB protein gradually strengthened.

益气散结方对气阴两虚型食管癌化疗患者Th17/Treg免疫平衡及NF-κB蛋白含量的影响

目的:探讨益气散结方对气阴两虚型食管癌化疗患者Th17/Treg免疫平衡及NF-κB蛋白含量的影响。方法:选取2014年3月至2017年3月于山东省东营市胜利医院就诊的60例气阴两虚型食管癌患者,随机分为研究组、对照组,每组30例。对照组给予紫杉醇联合顺铂治疗,研究组在此基础上给予益气散结方治疗,比较两组治疗效果、不良反应发生率,以及治疗前后(随访18个月)Th17/Treg免疫平衡、NF-κB含量及生存质量(KPS评分),比较两组生存率。结果:两组治疗总有效率差异无统计学意义(P>0.05);与对照组相比,研究组治疗后Th17/Treg、NF-κB p50、p65蛋白含量、Ⅰ~Ⅱ级恶心、呕吐发生率降低,KPS评分升高(P<0.05);两组治疗后12、16、18个月生存率差异无统计学意义(P>0.05)。结论:益气散结方可用于气阴两虚型食管癌化疗患者治疗,调控NF-κB表达,纠正Th17/Treg免疫失衡,增强机体免疫抵抗力,降低恶心、呕吐发生率,提升生存质量。

Expression of high mobility group protein B1 in the lungs of rats with sepsis

BACKGROUND： Vibrio vulnifi cus inside the body could activate the NF-!B signaling pathwayand initiate the inflammatory cascade. The lung is one of the earliest organs affected by sepsisassociated with acute lung injury. High mobility group protein B1 （HMGB1） is an important late-actingpro-infl ammatory cytokine involving in the pathophysiology of sepsis. It is also involved in the injuryprocess in the lung, liver and intestine. There has been no report on the involvement of HMGB1 inVibrio vulnifi cus sepsis-induced lung injury.METHODS： Sixty rats were randomly divided into a normal control group （group A, n=10） anda Vibrio vulnificus sepsis group （group B, n=50）. Sepsis was induced in the rats by subcutaneousinjection of Vibrio vulnificus （concentration 6×108 cfu/mL, volume 0.1 mL/100g）） into the left lowerlimbs. The rats in group B were sacrifi ced separately 1, 6, 12, 24, and 48 hours after the infection.Their lungs were stored as specimens, lung water content was measured, and lung pathology wasobserved under a light microscope. The expressions of the HMGB1 gene and protein in the lungswere detected by RT-PCR and Western blot. Data were analyzed with one-way analysis of variance（ANOVA） and the LSD method for pair-wise comparison between the two groups. P〈0.05 wasconsidered statistically signifi cant.RESULTS： Compared to group A （0.652±0.177）, HMGB1 mRNA expression in the lungs ofgroup B was signifi cantly higher at 0 hour （1.161±0.358, P=0.013）, 24 hours （1.679±0.235, P=0.000）,and 48 hours （1.258±0.274, P=0.004） （P〈0.05）, and peaked at 24 hours. Compared to group A（0.594±0.190）, HMGB1 protein expression at 6 hours （1.408±0.567, P=0.026） after infection wassignificantly increased （P〈0. 05）, and peaked at 24 hours （2.415±1.064, P=0.000） after infection.Compared to group A （0.699±0.054）, lung water content was significantly increased at 6 hours（0.759±0.030, P=0.001）,12 hours （0.767±0.023, P=0.000）, 24 hours （0.771±0.043, P=0.000） and 48hours （0.789±0.137, P=0.000） after infection （P〈0.05）. Compared to group A, pathological changesat 12 hours in group B indicate marked pulmonary vascular congestion, interstitial edema andinfl ammatory infi ltration. Alveolar cavity collapse and boundaries of the alveolar septum could not beclearly identifi ed.CONCLUSION： Vibrio vulnifi cus sepsis can lead to injury in rat lungs, and increased HMGB1expression in lung tissue may be one of the mechanisms for injury from Vibrio vulnifi cus sepsis.

Proteomics identifies a novel role of fibrinogen-like protein 1 in Crohn’s disease

BACKGROUND Crohn’s disease(CD)is an incurable intestinal disorder with unclear etiology and pathogenesis.Currently,there is a lack of specific biomarkers and drug targets for CD in clinical practice.It is essential to identify the precise pathophysiological mechanism of CD and investigate new therapeutic targets.AIM To explore a new biomarker and therapeutic target for CD and verify its role in the CD pathological mechanism.METHODS Proteomics was performed to quantify the protein profile in the plasma of 20 CD patients and 20 matched healthy controls.Hub genes among the selected differentially expressed proteins(DEPs)were detected via the MCODE plugin in Cytoscape software.The expression level of one hub gene with an immunoregulatory role that interested us was verified in the inflamed intestinal tissues of 20 CD patients by immunohistochemical analysis.After that,the effects of the selected hub gene on the intestinal inflammation of CD were identified in a CD cell model by examining the levels of proinflammatory cytokines by enzymelinked immunosorbent assays and the expression of the NF-κB signalling pathway by quantitative real-time PCR analysis and Western blot assays.RESULTS Thirty-five DEPs were selected from 393 credible proteins identified by proteomic analysis.Among the DEPs,fibrinogen-like protein 1(FGL1),which attracted our attention due to its function in the regulation of the immune response,had 1.722-fold higher expression in the plasma of CD patients and was identified as a hub gene by MCODE.Furthermore,the expression of FGL1 in the intestinal mucosal and epithelial tissues of CD patients was also upregulated(P<0.05).In vitro,the mRNA levels of FGL1 and NF-κB;the protein expression levels of FGL1,IKKα,IKKβ,p-IKKα/β,p-IκBα,and p-p65;and the concentrations of the proinflammatory cytokines IL-1β,IL-6,IL-17,and TNF-αwere increased(P<0.05)after stimulation with lipopolysaccharide,which were reversed by knockdown of FGL1 with siRNA transfection(P<0.05).Conversely,FGL1 overexpression enhanced the abovementioned results(P<0.05).CONCLUSION FGL1 can induce intestinal inflammation by activating the canonical NF-κB signalling pathway,and it may be considered a potential biomarker and therapeutic target for CD.

EYA4通过抑制NF-κB依赖的RAP1反式激活抑制肝细胞癌的生长和侵袭

背景与目的我们之前研究表明,眼缺失蛋白同源物4(eyes absent homolog 4,EYA4)是果蝇眼部发育相关的眼缺乏蛋白家族成员之一,在肝细胞癌(hepatocellular carcinoma,HCC)标本中常发生甲基化和沉默,并与患者生存期短密切相关。本研究旨在探讨EYA4在HCC中作为肿瘤抑制因子的作用机制。方法转染EYA4表达质粒(pEYA4)构建稳定表达EYA4的人HCC细胞系Huh-7和PLC/PRF/5(PLC)。通过BALB/c裸鼠皮下注射稳定转染细胞建立异种移植肿瘤。组织标本来自75例病理诊断为HCC的患者。采用实时定量聚合酶链式反应(real-time polymerase chain reaction,real-time PCR)、蛋白质免疫印迹和免疫组织化学的方法检测EYA4在细胞系、异种移植物和临床标本中的表达;研究了稳定转染细胞系的细胞增殖、克隆形成、侵袭性和肿瘤形成。利用基因表达芯片筛选EYA4调节的基因。通过共转染EYA4和带Flag标签的RAS相关蛋白1A(RAS-related protein 1A,RAP1A)基因的表达质粒(pEYA4和Flag-RAP1A)、功能研究、染色质免疫共沉淀、免疫荧光染色和细胞泛素化分析等方法,研究了EYA4对核因子-κB(nuclear factor-κB,NF-κB)/RAS相关蛋白1(RAS-related protein 1,RAP1)信号通路的影响。结果恢复HCC细胞系中EYA4的表达可抑制细胞的增殖、抑制克隆形成、降低细胞的侵袭性和抑制异种移植肿瘤生长,在体外实验中Flag-RAP1A可逆转pEYA4的抑制作用。用肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)激活NF-κB通路可增加p65与RAP1A基因启动子的结合并上调RAP1蛋白的表达。用BAY 11-7085和p65 siRNA抑制NF-κB通路,成功阻断了TNF-α诱导的RAP1上调。EYA4拮抗了TNF-α诱导的NF-κB抑制因子α(inhibitor of NF-κBα,IκBα)的磷酸化和泛素化以及p65的核易位和反式激活,进而抑制了NF-κB的活性和RAP1的表达。用calyculin A阻断EYA4的丝氨酸/苏氨酸磷酸酶活性可显著消除其对NF-κB活性的抑制作用。此外,EYA4的表达与HCC临床标本中IκBα/RAP1活性呈负相关。结论我们的研究结果为明确EYA4是真正的肿瘤抑制因子提供了功能和机制的理论基础,该肿瘤抑制因子可抑制NF-κB/RAP1信号通路的异常激活,从而抑制HCC生长和侵袭。

IcarisideⅡ inhibits lipopolysaccharide-induced inflammation and amyloid production in astrocytes by regulating IKK/IκB/NF-κB signaling pathway

OBJECTIVE To investigate the effect of icariin Ⅱ(ICS Ⅱ) on lipopolysaccharide(LPS)-induced inflammation and amyloid production in astrocytes.METHODS The cerebral cortex of newborn SD rats was isolated in vitro,and the primary astrocytes were extracted and cultured.Astrocytes were pre-treated with ICSⅡ(5,10 and20 μmol·L^(-1)) or dexamethasone(1 μmol·L^(-1)) for1 h.Cell inflammation models were established with LPS and treated with ICS Ⅱ or dexamethasone for another 24 h.The anti-neuroinflammation and anti-amyloid effects of ICS Ⅱ in astrocytes were detected by ELISA and Western blotting respectively.RESULTS ICS Ⅱ decreased the levels of beta secretase 1(BACE1),Aβ1-40 and Aβ1-42 in astrocytes in a concentration-dependent manner.Moreover,the levels of tumor necrosis factor-alpha,interleukin-1β,reactive oxygen species,inducible nitric oxide synthase,cyclooxygenase-2 and transforming growth factor-β1 in astrocytes were significantly inhibited by ICS II(5,10 and 20 μmol·L^(-1)).In addition,ICSⅡhas a significant inhibitory effect on LPS-induced IκB-α degradation and NF-κB activation.CONCLUSION ICS Ⅱ exerts neuroprotective effects on LPS-induced inflammation in astrocytes,through regulating IKK/IκB/NF-κB signaling pathway.

Hepatitis C virus non-structural 5A protein can enhance full-length core protein-induced nuclear factor-κB activation

AIM： To study the effects of hepatitis C virus （HCV） core and non-structural 5A （NS5A） proteins on nuclear factor- k B （NF- k B） activity for understanding their biological function on chronic hepatitis caused by HCV infection. METHODS： Luciferase assay was used to measure the activity of NF-kB in three different cell lines cotransfected with a series of deletion mutants of core protein alone or together with NS5A protein using pNF- k B-Luc as a reporter plasmid. Western blot and indirect immunofluorescence assays were used to confirm the expression of proteins and to detect their subcellular localization, respectively. Furthermore, Western blot was also used to detect the expression levels of NF- k B/p65, NF- k B/p50, and inhibitor k B-a（k B-a）. RESULTS： The wild-type core protein （C191） and its mutant segments （C173 and C158） could activate NF- k B in Huh7 cells only and activation caused by （C191） could be enhanced by NS5A protein. Moreover, the full-length core protein and its different deletion mutants alone or together with NS5A protein did not enhance the expression level of NF- k B. The NF- k B activity was augmented due to the dissociation of NF-k： B-I k： B complex and the degradation of Ik B-a. CONCLUSION：NF- k B is the key transcription factor that can activate many genes that are involved in the cellular immune response and inflammation. Coexpression of the full-length core protein along with NS5A can enhance the NF- k B activation, and this activation may play a significant role in chronic liver diseases including hepatocellular carcinoma associated with HCV infection.

IKIP downregulates THBS1/FAK signaling to suppress migration and invasion by glioblastoma cells

Background:Inhibitor of NF-κB kinase-interacting protein(IKIP)is known to promote proliferation of glioblastoma(GBM)cells,but how it affects migration and invasion by those cells is unclear.Methods:We compared levels of IKIP between glioma tissues and normal brain tissue in clinical samples and public databases.We examined the effects of IKIP overexpression and knockdown on the migration and invasion of GBM using transwell and wound healing assays,and we compared the transcriptomes under these different conditions to identify the molecular mechanisms involved.Results:Based on data from our clinical samples and from public databases,IKIP was overexpressed in GBM tumors,and its expression level correlated inversely with survival.IKIP overexpression in GBM cells inhibited migration and invasion in transwell and wound healing assays,whereas IKIP knockdown exerted the opposite effects.IKIP overexpression in GBM cells that were injected into mouse brain promoted tumor growth but inhibited tumor invasion of surrounding tissue.The effects of IKIP were associated with downregulation of THBS1 mRNA and concomitant inhibition of THBS1/FAK signaling.Conclusions:IKIP inhibits THBS1/FAK signaling to suppress migration and invasion of GBM cells.

紫外线(UV-B)照射对水稻产量及稻米蛋白质含量的影响

以抗紫外线UV B的日本粳稻品种Sasanishiki为材料 ,1999年和 2 0 0 0年在大田条件下 ,探讨了不同生育时期的UV B处理对水稻产量、糙米的大小及蛋白质含量的影响。结果表明 ,营养生长期 (移栽至幼穗分化 )、生殖生长期 (幼穗分化至抽穗 )及抽穗成熟期的UV B处理对Sasanishiki的产量及其构成因素的影响不显著 ;生殖生长期 (幼穗分化至抽穗 )与抽穗成熟期的UV B处理 ,使大粒米的比例减少 ;抽穗成熟期的UV B处理 ,增加了糙米中全N和贮藏蛋白的含量 ,其中主要是谷蛋白含量的增加 ,对水溶 盐溶蛋白和醇溶蛋白则影响较小。

利用RNAi抑制B-hordein合成降低大麦籽粒蛋白质含量

【目的】通过RNAi策略抑制大麦籽粒B-hordein的表达,获得高氮肥水平下籽粒蛋白质含量降低的转基因大麦新种质,探索大麦品质改良新途径。【方法】采用同源PCR技术克隆大麦B-hordein核心保守序列,通过Gateway技术构建大麦B-hordein的RNAi植物表达载体pBract207-zz-gp4,利用农杆菌介导法转化大麦Golden Promise幼胚,获得转基因植株。通过PCR检测、Southern杂交验证RNAi构件在转基因大麦及其后代基因组的整合情况。采用半定量RT-PCR分析转基因大麦花后不同发育时期B-hordein转录表达情况。基于近红外谷物分析仪测定蛋白质含量,并进行醇溶蛋白SDS-PAGE检测,以筛选蛋白质含量降低的转基因大麦株系。开展氮肥运筹相关试验,检验RNAi效率及高氮肥水平下转基因大麦蛋白质含量变化情况。【结果】获得大麦B-hordein片段2条(Gp4和Gp5),测序结果表明该片段大小为349 bp,聚类分析表明该序列跟已知大麦醇溶蛋白基因同源性最高达92%,与该基因已登录的mRNA序列同源性高于98%,确认所得片段为大麦B醇溶蛋白基因片段。利用Gateway技术将Gp4片段正反向插入载体pBract207,反向重复序列用i18和iv2 intron连接,构建了Ubi启动子驱动的大麦B-hordein RNAi植物表达载体pBract207-zz-gp4。通过农杆菌介导转化大麦Golden Promise幼胚,结合目标基因及筛选标记基因的PCR验证,获得含有RNAi构件及筛选标记基因的转基因大麦株系11个。Southern杂交检测表明RNAi构件已经稳定整合到T2/T3转基因大麦基因组。随机选取6个T3转基因大麦株系,半定量RT-PCR结果表明花后不同发育时期转基因大麦籽粒B-hordein表达水平明显低于非转基因对照,20 d时转基因株系表达量不仅相比同期对照降低28.19%—55.19%,而且在各时期中也最低。利用随机选取的T1和T3籽粒进行蛋白质含量测定表明8个转基因大麦株系的蛋白质含量相比非转基因对照显著降低,SDS-PAGE电泳结果显示与非转基因相比,转基因各株系B-醇溶蛋白比率有不同程度降低,其中3个株系B-醇溶蛋白比率降低明显,平均减幅为49.42%。采用蛋白质含量降低的转基因大麦株系RNAi-20开展氮肥运筹试验,结果表明,高氮肥水平HN2及HN3处理,该株系蛋白质含量显著低于非转基因对照;施以等量高氮肥时,伴随氮肥后移(HN2到HN3),该株系总蛋白含量相对非转基因对照逐渐降低。SDS-PAGE电泳结果显示B醇溶蛋白含量降低,电泳带型发生变化。【结论】RNAi技术能抑制籽粒B-hordein表达,降低B-醇溶蛋白含量,高氮肥水平下能显著降低大麦蛋白质含量。

雷公藤内酯醇对Aβ1-40诱导的小胶质细胞核因子-kappa B活化的影响

阿尔茨海默病（Alzheimer disease，AD）是以进行认知障碍和记忆能力损害为主要临床表现的大脑退变性疾病，多数学者认为其病因与β-淀粉样蛋白（beta-amyloid protein，Aβ）沉积激活小胶质细胞引起的炎症反应和神经毒性作用有关，其中核因子-κB（nuclear factor-κB，NF-κB）在这一过程起关键作用。雷公藤内酯醇是雷公藤中主要有效成分之一，具有显著的抗炎免疫调节作用，可通过抑制免疫细胞中的NF-κB活性发挥其药理作用。故本实验拟用Aβ1-40诱导体外培养的原代小胶质细胞，建立AD体外细胞模型，并给予不同剂量雷公藤内酯醇进行干预，

Osteoclast fusion and regulation by RANKL-dependent and independent factors

Osteoclasts are the bone resorbing cells essential for bone remodeling.Osteoclasts are formed from hematopoietic progenitors in the monocyte/macrophage lineage.Osteoclastogenesis is composed of several steps including progenitor survival,differentiation to mononuclear pre-osteoclasts,fusion to multi-nuclear mature osteoclasts,and activation to bone resorbing osteoclasts.The regulation of osteoclastogenesis has been extensively studied,in which the receptor activator of NF-κB ligand(RANKL)-mediated signaling pathway and downstream transcription factors play essential roles.However,less is known about osteoclast fusion,which is a property of mature osteoclasts and is required for osteoclasts to resorb bone.Several proteins that affect cell fusion have been identified.Among them,dritic cell-specific transmembrane protein(DC-STAMP)is directly associated to osteoclast fusion in vivo.Cytokines and factors influence osteoclast fusion through regula-tion of DC-STAMP.Here we review the recently discovered new factors that regulate osteoclast fusion with specific focus on DC-STAMP.A better understanding of the mechanistic basis of osteoclast fusion will lead to the development of a new therapeutic strategy for bone disorders due to elevated osteoclast bone resorption.Cell-cell fusion is essential for a variety of cellular biological processes.In mammals,there is a limited number of cell types that fuse to form multinucleated cells,such as the fusion of myoblasts for the formation of skeletal muscle and the fusion of cells of the monocyte/macrophage lineage for the formation of multinucleated osteoclasts and giant cells.In most cases,cellcell fusion is beneficial for cells by enhancing function.Myoblast fusion increases myofiber size and diameter and thereby increases contractile strength.Multinucleated osteoclasts have far more bone resorbing activity than their mono-nuclear counterparts.Multinucleated giant cells are much more efficient in the removal of implanted materials and bacteria due to chronic infection than macrophages.Therefore,they are also called foreign-body giant cells.Cell fusion is a complicated process involving cell migration,chemotaxis,cell-cell recognition and attachment,as well as changes into a fusion-competent status.All of these steps are regulated by multiple factors.In this review,we will discuss osteoclast fusion and regulation.

Orientin and vitexin attenuate lipopolysaccharide-induced inflammatory responses in RAW264.7 cells:a molecular docking study,biochemical characterization,and mechanism analysis

Plant flavonoids have received considerable attention for their health benefits.However,structure-activity relationships between flavonoids such as orientin and vitexin with similar structures are rarely reported.In the present study,molecular docking study suggested that orientin and vitexin suppressed inflammatory responses through the modulation of the mitogen-activated protein kinase(MAPK)signaling pathway.Moreover,RAW264.7 cells with lipopolysaccharide-induced inflammation were used to evaluate the anti-inflammatory activities of orientin and vitexin,based on the inflammation-related cytokines production,quantitative real-time reverse transcription PCR,and western blotting analysis.As a result,orientin or vitexin attenuated inflammatory responses through modulation of the MAPK/NF-κB signaling pathway by suppressing NF-κB translocation.

PM_(2.5) obtained from urban areas in Beijing induces apoptosis by activating nuclear factor-kappa B

Background: Particulate matter(PM), which has adverse effects on citizen health, is a major air pollutant in Beijing city. PM_(2.5) is an indicator of PM in urban areas and can cause serious damage to human health. Many epidemiological studies have shown that nuclear factor-kappa B(NF-κB) is involved in PM_(2.5)-induced cell injury, but the exact mechanisms are not well understood.Methods: The cytotoxic effects of PM_(2.5) at 25–1600μg/ml for 24 h were determined by MTT assay in Chinese hamster ovary cells(CHO) cells. Flow cytometry was used to determine the apoptosis rate induced by PM_(2.5). The destabilized enhanced green fluorescent protein(d2 EGFP) green fluorescent protein reporter system was used to determine the NF-κB activity induced by PM_(2.5). The expression of pro-apoptotic Bcl-2-associated death promoter(BAD) proteins induced by PM_(2.5) was determined by Western blotting to explore the relationship between PM_(2.5) and the NF-κB signaling pathway and to determine the toxicological mechanisms of PM_(2.5).Results: PM_(2.5) collected in Beijing urban districts induces cytotoxic effects in CHO cells according to MTT assay with 72.28% cell viability rates even at 200μg/ml PM_(2.5) and flow cytometry assays with 26.97% apoptosis rates at 200μg/ml PM_(2.5). PM_(2.5) increases the activation levels of NF-κB, which have maintained for 24 h. 200μg/ml PM_(2.5) cause activation of NF-κB after exposure for 4 h, the activation peak appears after 13.5 h with a peak value of 25.41%. The average percentage of NF-κB activation in whole 24 h is up to 12.90% by 200μg/ml PM_(2.5). In addition, PM_(2.5) decreases the expression level of the pro-apoptotic protein BAD in a concentration-dependent manner.Conclusion: PM_(2.5) induces NF-κB activation, which persists for 24 h. The expression of pro-apoptotic protein BAD decreased with increased concentrations of PM_(2.5). These findings suggest that PM_(2.5) plays a major role in apoptosis by activating the NF-κB signaling pathway and reducing BAD protein expression.

SIGNAL MECHANISM OF INHIBITION OF BIFIDOBACTERIA ON GROWTH OF COLON CANCER

Objective: To explore the antitumor mechanisms of bifidobacteria adolescence in vivo. Methods: The content of extracellular signal regulated proteins (ERK)1/2, C-Jun N-terminal kinase (JNK), p38, c-fos and c-jun in nude mouse transplanted large bowel carcinoma was detected by using laser confocal microscopy. The expression of NF-κB was determined by immunohistochemistry. Results: After the nude mouse transplanted tumor was treated with bifidobacteria, the average fluorescent strength of ERK1/2, JNK, c-fos and c-jun was significantly lower than that in tumor control group (P<0.01). The average fluorescent strength of p38 was not obvious difference in the two groups (P>0.05). The positive cell density of NF-κB in large bowel carcinoma transplantation tumors in Bifidobacterium injection group was markedly lower than that in tumor group(P<0.01). Conclusion: bifidobacteria adolescence could markedly decrease the activity of ERK1/2 and JNK, the expression c-fos and c-jun, and the activity of NF-κB.

Albumin resuscitation protects against traumatic/hemorrhagic shock-induced lung apoptosis in rats

Objective: To determine the effects of albumin administration on lung injury and apoptosis in traumatic/hemorrhagic shock (T/HS) rats. Methods: Studies were performed on an in vivo model of spontaneously breathing rats with induced T/HS; the rats were subjected to femur fracture, ischemia for 30 min, and reperfusion for 20 min with Ringer's lactate solution (RS) or 5% (w/v) albumin (ALB), and the left lower lobes of the lungs were resected. Results: Albumin administered during reperfusion markedly attenuated injury of the lung and decreased the concentration of lactic acid and the number of in situ TdT-mediated dUTP nick-end labelling (TUNEL)-positive cells. Moreover, immunohistochemistry performed 24 h after reperfusion revealed increases in the level of nuclear factor κB (NF-κB), and phosphorylated p38 mitogen-activated protein kinase (MAPK) in the albumin-untreated group was down-regulated by albumin treatment when compared with the sham rats. Conclusion: Resuscitation with albumin attenuates tissue injury and inhibits T/HS-induced apoptosis in the lung via the p38 MAPK signal transduction pathway that functions to stimulate the activation of NF-κB.

自建Lowry法测定B型肉毒神经毒素蛋白质含量

目的:探究适宜的B型肉毒神经毒素中蛋白质含量测定方法。方法:分别应用《中国药典》四部(2020版)中蛋白质测定法项下福林酚法(药典方法)和自建的Lowry法(本方法)测定3批B型肉毒神经毒素中的蛋白质含量,比较两种方法的线性关系、精密度和准确度。结果:两种方法的线性都具有良好的相关性,药典方法和本方法线性绝对系数R2分别为0.9972和0.9987;两种方法都具有良好的精密度和重复性,但本方法的相对标准偏差更低。结论:自建的Lowry法更适合B型肉毒神经毒素中蛋白质含量的测定。