BAFF调节免疫性血小板减少症模型小鼠的Th17/Treg平衡的研究

目的:探讨B细胞激活因子(BAFF)对免疫性血小板减少症模型小鼠体内辅助性T细胞17(Th17)/调节性T细胞(Treg)平衡的调节作用和潜在机制。方法:制备豚鼠抗小鼠血小板抗血清(GP-APS),并将150只无特定病原级别的成年雄性BALB/c小鼠(7~8周龄)随机分为5组,每组30只。分别为对照组(空白对照)和ITP组(GP-APS诱导),ITP+rhBAFF组(ITP组联合静脉注射50μg/kg/50μL重组人BAFF蛋白),并在ITP+rhBAFF组处理的基础上分别联合Notch1的抑制剂(DAPT)或PI3K/Akt的抑制剂Polygalacin D(PGD),设立ITP+rhBAFF+DAPT组和ITP+rhBAFF+PGD组,除对照组和ITP组外,均为静脉注射给药,DAPT注射剂量100μg/kg;PGD注射剂量25μg/kg,静脉注射总体积均为50μL,每日1次。1周后取小鼠1mL外周血并分离血清和单个核细胞。用免疫荧光化学检测单个核细胞中BAFF和Notch1的定位。对外周血中的血小板进行计数。酶联免疫吸附法(ELSIA)检测小鼠外周血血清BAFF的水平。Western blot检测小鼠外周血单个核细胞中PI3K、AKT、Notch1、p-Akt(Thr308)、p-Akt(Ser473)的蛋白表达。流式细胞术检测单个核细胞中Th17/Treg的比例变化。结果:ITP小鼠外周血单个核细胞的BAFF与Notch1共定位在细胞膜。与对照组比较,ITP组BAFF、Notch1、p-Akt(Thr308)、p-Akt(Ser473)的表达增加,血小板数目和Treg比例减少,Th17比例增加(P<0.05)。与ITP组比较,ITP+rhBAFF组BAFF、Notch1、p-Akt(Thr308)、p-Akt(Ser473)的表达增加,血小板数目和Treg比例减少,Th17比例增加(P<0.05)。与ITP+rhBAFF组比较,ITP+rhBAFF+DAPT组BAFF、Notch1、p-Akt(Thr308)、p-Akt(Ser473)的表达降低,血小板数目和Treg比例增加,Th17比例降低(P<0.05)。与ITP+rhBAFF组比较,ITP+rhBAFF+PGD组BAFF、Notch1、p-Akt(Thr308)、p-Akt(Ser473)的表达降低,血小板数目和Treg比例增加,Th17比例降低(P<0.05)。结论:BAFF通过激活Notch1/PI3K/Akt信号通路促进免疫性血小板减少症模型小鼠体内Th17比例增加及Treg比例减少。

Hepatocellular carcinoma mouse models:Hepatitis B virusassociatedhepatocarcinogenesis and haploinsufficienttumor suppressor genes

The multifactorial and multistage pathogenesis of hepatocellular carcinoma(HCC)has fascinated a wide spectrum of scientists for decades.While a number of major risk factors have been identified,their mechanistic roles in hepatocarcinogenesis still need to be elucidated.Many tumor suppressor genes(TSGs)have been identified as being involved in HCC.These TSGs can be classified into two groups depending on the situation with respect to allelic mutation/loss in the tumors:the recessive TSGs with two required mutated alleles and the haploinsufficient TSGs with one required mutated allele.Hepatitis B virus(HBV)is one of the most important risk factors associated with HCC.Although mice cannot be infected with HBV due to the narrow host range of HBV and the lack of a proper receptor,one advantage of mouse models for HBV/HCC research is the numerous and powerfulgenetic tools that help investigate the phenotypic effects of viral proteins and allow the dissection of the dose-dependent action of TSGs.Here,we mainly focus on the application of mouse models in relation to HBV-associated HCC and on TSGs that act either in a recessive or in a haploinsufficient manner.Discoveries obtained using mouse models will have a great impact on HCC translational medicine.

Application of hepatitis B virus replication mouse model

AIM:To evaluate the value of the hepatitis B virus(HBV) replication mouse model with regard to several aspects of the study of HBV biology.METHODS:To evaluate the HBV replication mouse model in detecting the efficacy of anti-HBV agents,the interferon inducer polyinosinic-polytidylin acid(polyIC) and nucleotide analogues adefovir and entecavir were administered to mice injected with wild type pHBV4.1,and the inhibiting effect of these agents on HBV DNA replication was evaluated.To identify the model's value in a replication ability study of HBV drug-resistant mutants and a HBx-minus mutant,telbivudine resistance mutants(rtM204I,ayw subtype),adefovir resistance mutants(rtA181V + rtN236T,ayw subtype) and HBxminus mutants were injected respectively,and their corresponding HBV DNA replication intermediates in mouse liver were assessed.RESULTS:Compared with the wild type HBV replication mouse model without antiviral agent treatment,the HBV DNA replication intermediates of the polyICtreated group were decreased 1-fold;while in the entecavir-and adefovir-treated groups,the levels of HBV DNA replication intermediates were inhibited 13.6-fold and 1.4-fold,respectively.For the mouse models injected with telbivudine resistance mutant,adefovir resistance mutant and HBx-minus mutant,HBV DNA replication intermediates could still be detected,but the levels of HBV DNA replication intermediates of these mutants decreased 4.5-fold,5.6-fold and 2.9-fold respectively,compared with the mouse model with wild type HBV plasmid.CONCLUSION:The HBV replication mouse model we established was a useful and convenient tool to detect the efficacy of antiviral agents and to study the replication ability of HBV mutants in vivo.

TLR4-HMGB1-, MyD88- and TRIF-dependent signaling in mouse intestinal ischemia/reperfusion injury

AIM: To characterize high-mobility group protein 1-toll-like receptor 4(HMGB1-TLR4) and downstream signaling pathways in intestinal ischemia/reperfusion(I/R) injury.METHODS: Forty specific-pathogen-free male C57BL/6 mice were randomly divided into five groups(n = 8 per group): sham, control, anti-HMGB1, anti-myeloid differentiation gene 88(My D88), and anti-translocatingchain-associating membrane protein(TRIF) antibody groups. Vehicle with the control Ig G antibody, antiHMGB1, anti-My D88, or anti-TRIF antibodies(all 1 mg/kg, 0.025%) were injected via the caudal vein 30 min prior to ischemia. After anesthetization, the abdominal wall was opened and the superior mesenteric artery was exposed, followed by 60 min mesenteric ischemia and then 60 min reperfusion. For the sham group, the abdominal wall was opened for 120 min without I/R. Levels of serum nuclear factor(NF)-κB p65, interleukin(IL)-6, and tumor necrosis factor(TNF)-α were measured, along with myeloperoxidase activity in the lung and liver. Inaddition,morphologic changes that occurred in the lung and intestinal tissues were evaluated. Levels of m RNA transcripts encoding HMGB1 and NF-κB were measured by real-time quantitative PCR, and levels of HMGB1 and NF-κB protein were measured by Western blot. Results were analyzed using one-way analysis of variance.RESULTS: Blocking HMGB 1, MyD 8 8, and TRIF expression by injecting anti-HMGB1, anti-My D88, or anti-TRIF antibodies prior to ischemia reduced the levels of inflammatory cytokines in serum; NF-κB p65: 104.64 ± 11.89, 228.53 ± 24.85, 145.00 ± 33.63, 191.12 ± 13.22, and 183.73 ± 10.81(P < 0.05); IL-6: 50.02 ± 6.33, 104.91 ± 31.18, 62.28 ± 6.73, 85.90 ± 17.37, and 78.14 ± 7.38(P < 0.05); TNF-α, 43.79 ± 4.18, 70.81 ± 6.97, 52.76 ± 5.71, 63.19 ± 5.47, and 59.70 ± 4.63(P < 0.05) for the sham, control, anti-HMGB1, anti-My D88, and anti-TRIF groups, respectively(all in pg/m L).Antibodies also alleviated tissue injury in the lung and small intestine compared with the control group in the mouse intestinal I/R model. The administration of antiHMGB1, anti-My D88, and anti-TRIF antibodies markedly reduced damage caused by I/R, for which anti-HMGB1 antibody had the most obvious effect.CONCLUSION: HMGB1 and its downstream signaling pathway play important roles in the mouse intestinal I/R injury, and the effect of the TRIF-dependent pathway is slightly greater.

Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

Osteogenesis imperfecta（OI） comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI,many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B（ACVR2B） in a mouse model of type Ⅲ OI（oim）. Treatment of 12-week-old oim mice with ACVR2 B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy,wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system.

Expression of hepatitis B virus 1.3-fold genome plasmid in an SV40 T-antigen-immortalized mouse hepatic cell line

AIM:To investigate the expression of the hepatitis B virus(HBV)1.3-fold genome plasmid(pHBV1.3)in an immortalized mouse hepatic cell line induced by SV40T-antigen(SV40T)expression.METHODS:Mouse hepatic cells were isolated from mouse liver tissue fragments from 3-5 d old Kunming mice by the direct collagenase digestion method and cultured in vitro.The pRSV-T plasmid was transfected into mouse hepatic cells to establish an SV40LT-immortalized mouse hepatic cell line.The SV40LT-immortalized mouse hepatic cells were identified and transfected with the pHBV1.3 plasmid.The levels of hepatitis B surface antigen(HBsAg)and hepatitis B e antigen(HBeAg)in the supernatant were determined by an electrochemiluminescence immunoassay at 24,48,72 and 96 h after transfection.The expressions of HBsAg and hepatitis B c antigen(HBcAg)in the cells were investigated by indirect immunofluorescence analysis.The presence of HBV DNA replication intermediates in the transfected cells and viral particles in the supernatant of the transfected cell cultures was monitored using the Southern hybridization assay and transmission electronic microscopy,respectively.RESULTS:The pRSV-T plasmid was used to immortalize mouse hepatocytes and an SV40LT-immortalized mouse hepatic cell line was successfully established.SV40LT-immortalized mouse hepatic cells have the same morphology and growth characteristics as primary mouse hepatic cells can be subcultured and produce albumin and cytokeratin-18 in vitro.Immortalized mouse hepatic cells did not show the characteristics of tumor cells,as alpha-fetoprotein levels were comparable(0.58±0.37 vs 0.61±0.31,P=0.37).SV40LTimmortalized mouse hepatic cells were then transfected with the pHBV1.3 plasmid,and it was found that the HBV genome replicated in SV40LT-immortalized mouse hepatic cells.The levels of HBsAg and HBeAg continuously increased in the supernatant after the transfection of pHBV1.3,and began to decrease 72 h after transfection.The expressions of HBsAg and HBcAg were observed in the pHBV1.3-transfected cells.HBV DNA replication intermediates were also observed at72 h after transfection,including relaxed circular DNA,double-stranded DNA and single-stranded DNA.Furthermore,a few 42 nm Dane particles,as well as many22 nm subviral particles with a spherical or filamentous shape,were detected in the supernatant.CONCLUSION:SV40T expression can immortalize mouse hepatic cells,and the pHBV1.3-transfected SV40T-immortalized mouse hepatic cell line can be a new in vitro cell model.

Contributions of transgenic mouse studies on the research of hepatitis B virus and hepatitis C virus-induced hepatocarcinogenesis

Transgenic mouse technology has enabled the investigation of the pathogenic effects, including those on development, immunological reactions and carcinogenesis, of viral genes directly in living organism in a real-time manner. Although viral hepatocarcinogenesis comprises multiple sequences of pathological events, that is, chronic necroinflammation and the subsequent regeneration of hepatocytes that induces the accumulation of genetic alterations and hepatocellular carcinoma(HCC), the direct action of viral proteins also play significant roles. The pathogenesis of hepatitis B virus X and hepatitis C virus(HCV) core genes has been extensively studied by virtue of their functions as a transactivator and a steatosis inducer, respectively. In particular, the mechanism of steatosis in HCV infection and its possible association with HCC has been well studied using HCV core gene transgenic mouse models. Although transgenic mouse models have remarkable advantages, they are intrinsically accompanied by some drawbacks when used to study human diseases. Therefore, the results obtained from transgenic mouse studies should be carefully interpreted in the context of whether or not they are well associated with human pathogenesis.

Establishment and Application of Hepatitis B Virus Persistent Replication Model in IFNAR^(-/-) Mouse

Summary： The type I interferon and IFNAR play an important role in hepatitis B virus （HBV） infection and anti-HBV therapy. However, its mechanism of action is still poorly understood. To gain more in- sights into the role of type I interferon and type I interferon receptor （IFNAR） in HBV infection, we established an HBV persistent replication IFNAR knockout （IFNAR-/-） mouse model and preliminarily applied this model. At first, the progeny of IFNAR-/- mouse was reproduced. Then hydrodynamic injec- tion with pAAV/HBV1.2 plasmid was conducted to establish the persistent HBV replication IFNAR-/- mouse model. At last, we applied this model to evaluate the effect of nucleoside analogues entecavir （ETV） on HBV replication. It was found that there was no difference in the serum HBsAg and HBeAg levels and HBcAg expression in the liver tissue between the ETV treated groups and normal saline （NS） treated group, but the serum HBV DNA levels were significantly suppressed 10, 25, 40 and 55 days af- ter the ETV treatment [P=0.035, P=0.00, P=0.149 and P=-0.084, IFNAR knockout （KO） control group vs. C57BL/6 ETV groups, respectively; P=0.081, P=0.001, P=0.243 and P=-0.147, IFNAR KO control group vs. IFNAR KO ETV groups, respectively]. Interestingly, there was no difference in serum HBV DNA levels between the ETV treated IFNAR/- and C57BL/6 mice. This result suggests that HBV sup- pression during ETV treatments doesn＇t depend on type Ⅰinterferon and IFNAR. Collectively, persis- tent HBV replication IFNAR/ mouse model that we established is a useful and convenient tool to detect the function of the type Ⅰ interferon and IFNAR in HBV infection and anti-HBV treatments.

Nuclear Factor kappa B p65 Expression in Mouse Cochlea

Nuclear factor kappa B(NF-κB) is one of the best-characterized transcription factors playing important roles in many cellular responses to a large variety of stimuli,including inflammatory cytokines, phorbol esters, growth factors, and bacterial and viral products. The aim of this study is to demonstrate NF-κB expression in the mouse cochlea and its enhancement in response to lipopolysaccharides(LPS) and kanamycin(KA) treatment. Methods KA treatment consisted of subcutaneous KA injections at 700 mg/kg twice a day with an eight-hour interval between the two injections for 3 or 7 days. For animals in the LPS treatment group, a single dose of 0.3 mg LPS dissolved in 0.2 ml sterile saline were injected into both bullae through the tympanic membrane and kept there for 3 hours. Animals in the control group received subcutaneous saline injection for 7 days. Following immmunohistochemichal processing with rabbit polyclonal anti-NF-κB p65 antibodies, cryosections of the cochlea were examined for expression of NF-κB p65 in various structures in the cochlea. Results NF-κB p65 expression, identified by presence of brown reaction products characteristic of DAB immunohistochemistry, was visible in the spiral ligament, spiral prominence, tectorial membrane(TM), spiral ganglion and nerve fibers. Relatively weak NF-κB p65 expression was also visualized in the organ of Corti. Within the organ of Corti, the inner hair cells(IHC), outer hair cells(OHC), inner pillar cells(IP), outer pillar cells (OP), Deiter’s cells(DC), and Boettcher’s cells exhibited stronger staining than the inner sulcus cells, Hensen’s cells(HC) and Claudius’cells. No NF-κB p65 expression was seen in the nucleus of the IHC and OHC. NF-κB p65 expression was increased in animals exposed to LPS or KA, demonstrating significant differences in the staining between control animals and LPS/KA-treated animals. NF-κB p65 expression was not significantly different between LPS treated and KA treated animals or between 3 and 7 days in KA-treated animals. Conclusion LPS and KA exposure increases expression of NF-κB p65 in the mouse cochlea.

原代Ph^(+)骨髓细胞的获取及小鼠Ph^(+)B-ALL模型的建立

目的:制备小鼠费城染色体阳性(Ph^(+))原代细胞并构建B淋巴细胞白血病(B-ALL)小鼠模型。方法:利用逆转录病毒将带有BCR-ABL P210融合基因的质粒转入C57BL/6J小鼠骨髓细胞中,输注给9 Gy总致死剂量60Coγ射线照射的同系小鼠后建立第一代Ph^(+)骨髓细胞的小鼠模型,然后获取发病小鼠脾脏和骨髓的原代细胞冻存。C57BL/6J小鼠经亚致死剂量照射后,接受第一代Ph^(+)细胞进行体内传代,顺序传代获得第三、四代Ph^(+)细胞及小鼠B-ALL模型。分别应用流式细胞术、H&E染色、外周血涂片等对建模小鼠进行免疫表型分析及病变检测。结果:输注含有P210-NGFR逆转录病毒的骨髓细胞后,小鼠出现体重明显下降、双下肢瘫痪、弓背等症状。发病小鼠的外周血涂片中可观察到原始和幼稚淋巴细胞。H&E染色结果显示,发病小鼠肝脏小叶中央静脉周围以及肝脏边缘有明显的白血病细胞浸润。流式细胞术检测结果显示,发病小鼠脾脏中CD19+NGFR+细胞随传代增加百分率逐渐升高,G1、G2和G3分别为19.0%、47.3%和61.0%。免疫表型分析结果表明,Ph^(+)细胞在B淋巴细胞中稳定传代,且随着传代增多Ph^(+)B淋巴细胞占比显著提高。结论:本研究成功制备小鼠Ph^(+)原代细胞,并顺利完成体内传代及B-ALL小鼠模型构建。

One extraction tool for in vitro-in vivo extrapolation?SPME-based metabolomics of in vitro 2D,3D,and in vivo mouse melanoma models

Solid phase microextraction(SPME)in combination with high-resolution mass spectrometry was employed for the determination of metabolomic profile of mouse melanoma growth within in vitro 2D,in vitro 3D,and in vivo models.Such multi-model approach had never been investigated before.Due to the low-invasiveness of SPME,it was possible to perform time-course analysis,which allowed building time profile of biochemical reactions in the studied material.Such approach does not require the multiplication of samples as subsequent analyses are performed from the very same cell culture or from the same individual.SPME already reduces the number of animals required for experiment;therefore,it is with good concordance with the 3Rs rule(replacement,reduction,and refinement).Among tested models,the largest number of compounds was found within the in vitro 2D cell culture model,while in vivo and in vitro 3D models had the lowest number of detected compounds.These results may be connected with a higher metabolic rate,as well as lower integrity of the in vitro 2D model compared to the in vitro 3D model resulting in a lower number of compounds released into medium in the latter model.In terms of in vitro-in vivo extrapolation,the in vitro 2D model performed more similar to in vivo model compared to in vitro 3D model;however,it might have been due to the fact that only compounds secreted to medium were investigated.Thus,in further experiments to obtain full metabolome information,the intraspheroidal assessment or spheroid dissociation would be necessary.

<i>In-Vitro</i>Effect of Sex Steroids on Mouse Melanoma (B16F10) Cell Growth

A battery of sex steroids were used to check their effect on mouse melanoma (B16F10) cell growth in-vitro. Progesterone and its synthetic receptor antagonist RU-486 showed maximum inhibition on in-vitro melanoma cell growth [1]. Further research work showed that the inhibition by progesterone was not a toxic, spurious or non-specific effect on mouse melanoma cell growth and the inhibition by progesterone was not mediated through progesterone receptor.

Molecular docking of DS-3032B,a mouse double minute 2 enzyme antagonist with potential for oncology treatment development

BACKGROUND It is known that p53 suppression is an important marker of poor prognosis of cancers,especially in solid tumors of the breast,lung,stomach,and esophagus;liposarcomas,glioblastomas,and leukemias.Because p53 has mouse double minute 2(MDM2)as its primary negative regulator,this molecular docking study seeks to answer the following hypotheses:Is the interaction between DS-3032B and MDM2 stable enough for this drug to be considered as a promising neoplastic inhibitor?AIM To analyze,in silico,the chemical bonds between the antagonist DS-3032B and its binding site in MDM2.METHODS For molecular docking simulations,the file containing structures of MDM2(receptor)and the drug DS-3032B(ligand)were selected.The three-dimensional structure of MDM2 was obtained from Protein Data Bank,and the one for DS-3032B was obtained from PubChem database.The location and dimensions of the Grid box was determined using AutoDock Tools software.In this case,the dimensions of the Grid encompassed the entire receptor.The ligand DS-3032B interacts with the MDM2 receptor in a physiological environment with pH 7.4;thus,to simulate more reliably,its interaction was made with the calculation for the prediction of its protonation state using the MarvinSketch®software.Both ligands,with and without the protonation,were prepared for molecular docking using the AutoDock Tools software.This software detects the torsion points of the drug and calculates the angle of the torsions.Molecular docking simulations were performed using the tools of the AutoDock platform connected to the Vina software.The analyses of the amino acid residues involved in the interactions between the receptor and the ligand as well as the twists of the ligand,atoms involved in the interactions,and type,strength,and length of the interactions were performed using the PyMol software(pymol.org/2)and Discovery Studio from BIOVIA®.RESULTS The global alignment indicated crystal structure 5SWK was more suitable for docking simulations by presenting the p53 binding site.The three-dimensional structure 5SWK for MDM2 was selected from Protein Data Bank and the three-dimensional structure of DS-3032B was selected from PubChem(Compound CID:73297272;Milademetan).After molecular docking simulations,the most stable conformer was selected for both protonated and non-protonated DS-3032B.The interaction between MDM2 and DS-3032B occurs with high affinity;no significant difference was observed in the affinity energies between the MDM2/pronated DS-3032B(-9.9 kcal/mol)and MDM2/non-protonated DS-3032B conformers(-10.0 kcal/mol).Sixteen amino acid residues of MDM2 are involved in chemical bonds with the protonated DS-3032B;these 16 residues of MDM2 belong to the p53 biding site region and provide high affinity to interaction and stability to drugprotein complex.CONCLUSION Molecular docking indicated that DS-3032B antagonist binds to the same region of the p53 binding site in the MDM2 with high affinity and stability,and this suggests therapeutic efficiency.

Inhibitory Effect of Cigarette Smoke Extract on Experimental Lung Metastasis of Mouse Melanoma by Suppressing Tumor Invasion

We investigated the effect of a nicotine-and tar-free cigarette smoke extract (CSE) using an experimental metastasis mouse model which was intravenously injected with B16-BL6 mouse melanoma cells. Three-hour pretreatment of cells with various concentrations of CSE (0, 0.1, 0.3, and 1%) dose-dependently reduced the number of lung metastatic nodules 14 days after tumor injection. To elucidate the mechanism of this anti-metastatic effect of CSE, we examined the invasion and migration activities of B16-BL6 cells pretreated with CSE for three hours in vitro. CSE significantly reduced the invasion of cells at 1% and the migration at 0.3% and 1%. Under the same pretreatment conditions, CSE had no effect on the proliferation of cells. These findings suggest that CSE contains some ingredients that suppress hematogenic lung metastasis via inhibition of the invasion and migration activities of mouse melanoma cells.

丹酚酸B通过线粒体凋亡途径干预动脉粥样硬化的作用机制研究

目的探讨丹酚酸B通过线粒体凋亡途径干预动脉粥样硬化(Atherosclerosis,AS)的作用机制。方法将小鼠单核巨噬细胞RAW264.7培养后分为空白组,细胞色素C(Cytochrome C,cytC)组,丹酚酸B低、中、高浓度组。各组干预时间均为24h。用噻唑蓝(MTT)实验检测细胞存活率,并用流式细胞仪检测细胞凋亡率。采用蛋白免疫印迹(Western Blotting)法分别检测cytC的释放和B淋巴细胞瘤-2基因(B-cell lymphoma-2,Bcl-2)、半胱天冬氨酸蛋白酶-3(Cysteinyl aspartate specific proteinase-3,Caspase-3)、半胱天冬氨酸蛋白酶-9(Cysteinyl aspartate specific proteinase-9,Caspase-9)和Bcl-2相关X蛋白质(Bcl-2-associated X protein,Bax)蛋白表达水平。结果与空白组比较,cyt C组细胞活性降低(P<0.05),细胞平均凋亡率较高(P<0.05);cyt C组中促凋亡蛋白cyt C、Bax、Caspase-3及Caspase-9的表达均升高(P<0.05),抑凋亡蛋白Bcl-2的表达下降(P<0.05)。与cytC组比较,丹酚酸B低、中浓度组细胞活性均上升(P<0.01,P<0.05),各组促凋亡蛋白cytC、Bax、Caspase-3及Caspase-9表达均下降(P<0.01,P<0.05),丹酚酸B中、低浓度组细胞中抑凋亡蛋白Bcl-2的表达升高(P<0.01)。丹酚酸B中、高浓度组与空白组细胞平均凋亡率比较,差异有显著统计学意义(P<0.01)。结论丹酚酸B通过降低cytC、Bax、Caspase-3、Caspase-9蛋白表达抑制cytC诱导的RAW264.7细胞凋亡,发挥在AS发展进程中改善粥样斑块沉积的作用,可能与抑制线粒体凋亡途径相关。

Effects of p75 neurotrophin receptor knockout on axonal regeneration in a mouse model of facial nerve injury

BACKGROUND： Previous studies have shown that p75 neurotrophin receptor plays an important role in peripheral nerve injury. However, the role of p75 neurotrophin receptor in the regeneration of peripheral nerves remains poorly understood. OBJECTIVE： To study the effect of p75 neurotrophin receptor on facial nerve regeneration. DESIGN, TIME AND SETTING： A randomized controlled experiment was performed in the Regeneration Laboratory of Flinders University, Australia and the Biomedical Laboratory of Dentistry School, Shandong University from March 2005 to February 2006. MATERIALS： Cholera toxin B subunit, fast blue, and biotin rabbit-anti goat IgG were provided by Sigma, USA; goat-anti choleratoxin B subunit ant/body was provided by List Biologicals, USA. METHODS： In p75 neurotrophin receptor knockout and wild type 129/sv mice, the facial nerves on one side were crushed. At days 2 and 4 following injury, regenerating motor neurons in the facial nuclei were labeled by fast blue, and the regenerating axon was labeled by the anterograde tracer choleratoxin B subunit. MAIN OUTCOME MEASURES： Axonal regenerative velocity and number were detected by immunohistochemical staining of choleratoxin B subunit, growth-associated protein, protein gene product 9.5, and calcitonin-gene-related peptide; survival of motor neurons in the facial nuclei was detected by retrograde fast blue. RESULTS： Axonal growth in the facial nerve of p75 neurotrophin receptor knockout mice was significantly less than in wild type mice. At day 7 after injury, the number of regenerating motor neurons in p75 neurotrophin receptor knockout mice remained significantly less than in wild type mice （P 〈 0.05）. The number of positively stained fibers for growth-associated protein-43, protein gene product 9.5, and calcitonin-gene-related peptide in p75 neurotrophin receptor knockout mice was significantly less than in wild type mice （P 〈 0.01）. CONCLUSION： p75 neurotrophin receptor promoted axonal regeneration and enhanced the survival rate of motor neurons following facial nerve injury.

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.

Anti-Melanogenesis Activity of Supercritical Carbon Dioxide Extract from Perilla frutescens Seeds

Perilla frutescens seed (PFS) oil is reported to inhibit skin photoaging;however, its effect on melanogenesis has not yet been investigated. Herein, we tested the anti-melanogenesis activity of an oil-based extract from PFS with supercritical carbon dioxide (scCO2). In a cell culture system, B16 mouse melanoma cells were treated with the PFS scCO2 extract and other samples. The PFS scCO2 extract decreased melanin production by approximately 90% in B16 mouse melanoma cells without cytotoxicity at 100 μg/mL. This effect was greater than that of the well-known melanogenesis inhibitor, kojic acid. Although a hexane-extracted PFS oil and a squeezed PFS oil also decreased melanin production in the B16 cells, the inhibitory effect of the PFS scCO2 extract was higher than both of these. Chemical analysis of the PFS scCO2 extract and squeezed PFS oil showed that almost 90% of the components of both oils were α-linolenic acid, linoleic acid, and oleic acid. Furthermore, the ratio of those three fatty acids across both samples was almost the same. When the three fatty acids were mixed in the same ratio as in the PFS scCO2 extract, the IC50 of the mixture for melanin production in B16 melanoma cells was identical to that of the PFS scCO2 extract. However, the IC50 of the squeezed PFS oil was approximately 6.6 times higher than that of the mixture. Although those fatty acids are the main inhibitory ingredients against melanin production in all of the extracts, some factor(s) in the squeezed PFS reduce their affinity with the cells. These results indicated that the PFS scCO2 extract could be a superior melanogenesis inhibitor. Although its main ingredients are probably the same as those of the squeezed PFS oil, it is necessary to extract with scCO2 for stronger anti-melanogenesis activity.