Retinoic acid inducible gene-I,more than a virus sensor

Retinoic acid inducible gene-I(RIG-I)is a caspase recruitment domain(CARD)containing protein that acts as an intracellular RNA receptor and senses virus infection.After binding to double stranded RNA(dsRNA)or 5′-triphosphate single stranded RNA(ssRNA),RIG-I transforms into an open conformation,translocates onto mitochondria,and interacts with the downstream adaptor mitochondrial antiviral signaling(MAVS)to induce the production of type Ⅰ interferon and inflammatory factors via IRF3/7 and NF-κB pathways,respectively.Recently,accumulating evidence suggests that RIG-I could function in non-viral systems and participate in a series of biological events,such as inflammation and inflammation related diseases,cell proliferation,apoptosis and even senescence.Here we review recent advances in antiviral study of RIG-I as well as the functions of RIG-I in other fields.

Molecular Cloning,Characterization and Expression Analysis of Woodchuck Retinoic Acid-Inducible GeneⅠ

Cytosolic retinoic acid-inducible gene I（RIG-I） is an important innate immune RNA sensor and can induce antiviral cytokines, e.g., interferon-β（IFN-β）. Innate immune response to hepatitis B virus（HBV） plays a pivotal role in viral clearance and persistence. However, knowledge of the role that RIG-I plays in HBV infection is limited. The woodchuck is a valuable model for studying HBV infection. To characterize the molecular basis of woodchuck RIG-I（w RIG-I）, we analyzed the complete coding sequences（CDSs） of w RIG-I, containing 2778 base pairs that encode 925 amino acids. The deduced w RIG-I protein was 106.847 k D with a theoretical isoelectric point（p I） of 6.07, and contained three important functional structures [caspase activation and recruitment domains（CARDs）, DEx D/H-box helicases, and a repressor domain（RD）]. In woodchuck fibroblastoma cell line（WH12/6）, w RIG-I-targeted small interfering RNA（si RNA） down-regulated RIG-I and its downstrean effector–IFN-β transcripts under RIG-I＇ ligand, 5＇-ppp double stranded RNA（ds RNA） stimulation. We also measured m RNA levels of w RIG-I in different tissues from healthy woodchucks and in the livers from woodchuck hepatitis virus（WHV）-infected woodchucks. The basal expression levels of w RIG-I were abundant in the kidney and liver. Importantly, w RIG-I was significantly up-regulated in acutely infected woodchuck livers, suggesting that RIG-I might be involved in WHV infection. These results may characterize RIG-I in the woodchuck model, providing a strong basis for further study on RIG-I-mediated innate immunity in HBV infection.

Retinoic acid metabolic change in retina and choroid of the guinea pig with lens-induced myopia

AIM: To investigate the role of retinoic add (RA) and retinaldehyde dehydrogenase-2 (RALDH(2)) of retina and choroid in the guinea pig lens-induced myopic eyes. METHODS: Totally 45 guinea pigs, at age of three weeks, were randomly assigned into three groups: the normal control, the lens-induced group and the recovering group. Out of focus was induced by the -6.00D concave lens on the left eye, and lasted for 15 days. All animals underwent biometric measurement (corneal radius of curvature, refraction and axial length). Subsequently, RA content in the retina and RPE/choriod complex was detected by reversed-phase high-performance liquid chromatography. RALDH(2) protein in the retina and RPE/choriod complex was evaluated by the immunohistochemical staining and Western blotting. RESULTS: After wearing -6.00D lens for 15 days, axial length of the lens-induced eye extends and myopia was formed, with RA contents increasing in both the neural retina and RPE/choroid complex. Comparing with the lens-induced group, myopic degree significantly relieved, and its RA contents in both the neural retina and RPE/choroid complex decreased in the recovering group. In the normal control, RALDH(2) protein was expressed positively in the retinal nerve fiber layer (RNFL), inner plexiform layer (IPL) and lateral border of outer nuclear layer (ONL). Retinal RALDH(2) protein increased in the lens-induced group, and was also positive in the outer plexiform layer (OPL). In the recovering group, retinal RALDH(2) protein attenuated the expression in the OPL turns to negative. RALDH(2) protein was not expressed in the choroid of any group. CONCLUSION: RA of retina and chorid participates in the regulation of the lens-induced myopia in guinea pigs, which may be related with retinal RALDH(2) protein.

THE DIFFERENTIATION INDUCING EFFECT OF TANSHINONE AND RETINOIC ACID ON HUMAN CERVICAL CARCINOMA CELL LINE（ME180） IN VITRO

The cervical carcinoma cell line, ME180 cells were treated with tanshinone (Tan) or retinoic acid (RA) in DMSO (final concentration 0.02%, V/V) on 4 successive days. The cells treated with the same concentration of DMSO alone served as control. Morphological studies with light and transmission electron microscopy showed that the cells treated with both Tan and RA became welldifferentiated. The cellular growth and proliferation were suppressed (as revealed by cell counting. [3H]-thymidine uptake and colony-forming assay). The number of nuclear organizer regions(AgNORs) in cells reduced and the distribution type returned nearly to normal type. The tumorigenicity in nude mice was reduced. The cell RNA dot hybridization showed that the expression of c-myc and c-Ha-ras mRNA was inhibited markedly. All above results showed that Tan and RA could reverse some malignant Phenotype and possessed differentiation inducing activity on ME180 cell line. No significant difference was observed between the cells treated with Tan and RA.

Optimal time point for the transplantation of neural stem cells induced to differentiate with retinoic acid

Previous studies have demonstrated that differentiated neural stem cells （NSCs） are more suitable for transplantation than non-differentiated NSCs. In this study, NSCs were expanded in vitro for two passages, induced with retinoic acid to differentiate, and harvested between 1 6 days later. They were subsequently cultured in artificial cerebrospinal fluid for an additional 3 days, dudng which their growth and morphology was monitored. NSCs induced for 4 days exhibited a peak rate of cells differentiating into neurons and robust growth. Our results indicate that the optimal time point for transplanting NSCs is following a 4-day period of induced differentiation.

Synergistic effects of brain-derived neurotrophic factor and retinoic acid on inducing the differentiation of bone marrow stromal cells into neuron-like cells in adult rats in vitro

BACKGROUND： Under induction of retinoic acid （RA）, bone marrow stromal cells （BMSCs） can differentiate into nerve cells or neuron-like cells, which do not survive for a long time, so those are restricted to an application. Other neurotrophic factors can also differentiate into neuronal cells through inducing BMSCs; especially, brain-derived neurotrophic factor （BDNF） can delay natural death of neurons and play a key role in survival and growth of neurons. The combination of them is beneficial for differentiation of BMSCs. OBJECTIVE： To investigate the effects of BDNF combining with RA on inducing differentiation of BMSCs to nerve cells of adult rats and compare the results between common medium group and single BDNF group. DESIGN： Randomized controlled animal study SETTING： Department of Neurology, Affiliated Hospital of Xuzhou Medical College MATERIALS： The experiment was carried out in the Clinical Neurological Laboratory of Xuzhou Medical College from September 2003 to April 2005. A total of 24 SD rats, of either gender, 2 months old, weighing 130-150 g, were provided by Experimental Animal Center of Xuzhou Medical College [certification： SYXK （su） 2002-0038]. Materials and reagents： low-glucose DMEM medium, bovine serum, BDNF, RA, trypsin, separating medium of lymphocyte, monoclonal antibody of mouse-anti-nestin, neuro-specific enolase, glial fibrillary acidic protein （GFAP） antibody, SABC kit, and diaminobenzidine （DAB） color agent. All these mentioned above were mainly provided by SIGMA Company, GIBCO Company and Boshide Company. METHODS： Bone marrow of SD rats was selected for density gradient centrifugation. BMSCs were undertaken primary culture and subculture; and then, those cells were induced respectively in various mediums in total of 3 groups, including control group （primary culture）, BDNF group （20 μg/L BDNF） and BDNF＋RA group （20 μg/L BDNF plus 20 μg/L RA）. On the 3^rd and the 7^th days after induction, BMSCs were stained immunocytochemically with nestin （sign of nerve stem cells）, neuron-specific enolase （NSE, sign of diagnosing neurons） and GFAP （diagnosing astrocyte）, and evaluated cellular property. MAIN OUTCOME MEASURES ： Induction and differentiation in vitro of BMSCs in 3 groups RESULTS： （1） Induction and differentiation of BMSCs： Seven days after induction, cells having 2 or more apophyses were observed. Soma shaped like angle or erose form, which were similar to neurons and glial cells having strong refraction. （2） Results of immunocytochemical detection： Three days after induction, rate of positive cells in BDNF＋RA group was higher than that in BDNF group and control group [（86.15±4.58）%, （65.43±4.23）%, （4.18±1.09）%, P 〈 0.01]. Seven days after induction, rate of positive cells was lower in BDNF group and BDNF＋RA group than that in both groups at 3 days after induction [（31.12±3.18）%, （29.35±2.69）%, P 〈 0.01]; however, amounts of positive cells of NSE and GFAP were higher than those at 3 days after induction （P 〈 0.01）; meanwhile, the amount in BDNF＋RA group was remarkably higher than that in BDNF group （P 〈 0.01）. CONCLUSION： Combination of BDNF and RA can cooperate differentiation of BMSCs into neurons and astrocyte, and the effect is superior to single usage of BDNF.

THE STUDY ON POST-REMISSION THERAPIES IN PATIENTS WITH APL AFTER COMPLETE REMISSION INDUCED BY ALL-TRANS RETINOIC ACID

As to determine the effect of post-remission therapy in prolonging survival and duration of remission after complete remission, 50 patients with APL In complete remission Induced by retinolc acid (RA) were divided into three groups randomly: (A) 30 cases, treated by alternate chemotherapy with RA; (B) 10 cases, with RA alone; (C) 10 cases, only with chemotherapy.The survival curves showed mat Group A had the survival time more than 1 year In 87. 4 %, more than 2 year in 80.7%. 26/30 cases were survival and still in remission, the survival curve tend to be a plateau at 16 months. In Group B more than 1 year in 45. 7%. In Group C, more than 1 year In 50%. (Keplan-Meler x2 = 8. 93 P <0. 01).This result showed that the alternate chemotherapy with RA for post- Induction remission therapy could be useful to Improve long-term survivors and to prolong the duration of remission.

EXPERIMENTAL STUDY OF THE DIFFERENTIATION HPV16 SUBGENES-IMMORTALIZED HUMAN ENDOCERVICAL CELLS INDUCED BY ALL-TRANS-RETINOIC ACID

Objective： To investigate the differentiation-inducing effects of all-trans-retinoic （ATRA） to HPV16 subgenesimmortalized human l：ndocervical cells （H8 cell） in vitro. Methods： HPV16 subgenes-immortalized human endocervical cells （H8 cells） were cultured in vitro. After treated with ATRA, the proliferation of immortalized human endocervical cells was measured by MTT assay; morphological changes were observed using M and TEM; cell cycle was analyzed by FCM; expression of Ki67 was tested using immunocytochemistry and the activity of telomerase was tested using PCR-ELISA. Results： ATRA could inhibit proliferation of H8 cells significantly and induce their morphodifferentiation. According to FCM, H8 cells accumulated in G1 phase and expression of Ki67 and activity of telomerase reduced significantly after treatment with ATRA. Conclusion： ATRA could induce the differentiation of H8 cell line obviously, which might be achieved by inhibiting proliferation, blocking cell cycle, and reducing activity of telomerase.

Andrographolide as An Anti-H1N1 Drug and the Mechanism Related to Retinoic Acid-Inducible Gene-I-Like Receptors Signaling Pathway

Objective： To observe the anti-virus effects of andrographolide （AD） on the retinoic acid-inducible gene-I （RIG-I）-Iike receptors （RLRs） signaling pathway when immunological cells were infected with HIN1. Methods： Leukomonocyte was obtained from umbilical cord blood by Ficoll density gradient centrifugation, and immunological cells were harvested after cytokines stimulation. Virus infected cell model was established by H1N1 co-cultured with normal human bronchial epithelial cell line （16HBE）. The optimal concentration of AD was defined by methyl-thiazolyl-tetrazolium （MTT） assay. After the virus infected cell model was established, AD was added into the medium as a treatment intervention. After 24-h co-culture, cell supernatant was collected for interferon gamma （IFN- ~, ） and interleukin-4 （IL-4） enzyme-linked immunosorbent assay （ELISA） detection while immunological cells for real-time polymerase chain reaction （RT-PCR）. Results： The optimal concentration of AD for anti-virus effect was 250 μg/mL. IL-4 and IFN-γ in the supernatant and mRNA levels in RLRs pathway increased when cells was infected by virus, RIG-I, IFN-13 promoter stimulator-1 （IPS-1）, interferon regulatory factor （IRF）-7, IRF-3 and nuclear transcription factor K B （NF- K B） mRNA levels increased significantly （P〈0.05）. When AD was added into co-culture medium, the levels of IL-4 and IFN-γ were lower than those in the non-interference groups and the mRNA expression levels decreased, RIG-I, IPS-1, IRF-7, IRF-3 and NF- K B decreased significantly in each group with significant statistic differences （P〈0.05）. Conclusions： The RLRs mediated viral recognition provided a potential molecular target for acute viral infections and andrographolide could ameliorate H1N1 virus-induced cell mortality. And the antiviral effects might be related to its inhibition of viral-induced activation of the RLRs signaling pathway.

参附注射液对失血性休克大鼠肺损伤的影响

目的观察参附注射液对大鼠失血性休克(HS)致肺损伤的影响并探讨潜在机制。方法选择SPF级健康雄性SD大鼠36只,16~17周龄,体重400~600 g。采用随机数字表法将大鼠分为三组:假手术组(SH组)、失血性休克组(HS组)和参附注射液组(SF组),每组12只。SH组麻醉后仅分离出右股静脉和股动脉,不行动静脉置管,HS组和SF组制备HS大鼠模型。HS组经静脉导管进行液体复苏,复苏液为所失自体血加1.5倍失血量的复方氯化钠注射液与生理盐水10 ml/kg,SF组复苏液为所失自体血加1.5倍失血量的复方氯化钠注射液与参附注射液10 ml/kg,灌注时间约60 min。于术后24、48 h随机处死6只大鼠,取肺组织检测湿重与干重比(W/D),采用ELISA法检测白细胞介素-6(IL-6)、IL-17、IL-10、转化生长因子-β(TGF-β)浓度,采用PCR法检测肺组织视黄酸相关孤核受体γt(RORγt)、叉头翼状螺旋转录因子3(Foxp3)、缺氧诱导因子1α(HIF-1α)mRNA表达量,采用Western blot法检测RORγt、Foxp3、HIF-1α、水通道蛋白1(AQP1)和AQP5蛋白含量,肺组织行HE染色后在光镜下观察病理学改变并行肺损伤评分。结果与术后24 h比较,术后48 h SF组肺组织W/D、IL-6和IL-17浓度、RORγt和HIF-1αmRNA表达量及蛋白含量、肺损伤评分均明显降低(P<0.05),IL-10和TGF-β浓度、Foxp3 mRNA表达量及蛋白含量、AQP1蛋白含量均明显升高(P<0.05)。与SH组比较,术后24、48 h HS组和SF组W/D、IL-6、IL-17、IL-10和TGF-β浓度、RORγt、Foxp3和HIF-1αmRNA表达量及蛋白含量、肺损伤评分均明显升高(P<0.05),AQP1、AQP5蛋白含量明显降低(P<0.05),光镜下可见肺泡结构破坏,肺泡间质充满大量水肿液,其间浸润着大量炎性细胞。与HS组比较,术后24、48 h SF组W/D、IL-6和IL-17浓度、RORγt和HIF-1αmRNA表达量及蛋白含量、肺损伤评分明显降低(P<0.05),IL-10和TGF-β浓度、Foxp3 mRNA表达量及蛋白含量、AQP1和AQP5蛋白含量均明显升高(P<0.05),光镜下可见肺泡结构紊乱改善,水肿程度减轻,炎性细胞数量减少。结论参附注射液可调节促炎因子IL-6、IL-17与抗炎因子IL-10、TGF-β平衡,升高肺组织AQP1、AQP5蛋白含量,降低肺组织W/D和肺损伤评分,减轻HS大鼠肺损伤,机制可能与调节HIF-1α-RORγt/Foxp3平衡有关。

Generation of male germ cells from induced pluripotent stem cells （iPS cells）： an in vitro and in vivo study

Recent studies have reported that induced pluripotent stem （iPS） cells from mice and humans can differentiate into primordial germ cells. However, whether iPS cells are capable of producing male germ cells is not known. The objective of this study was to investigate the differentiation potential of mouse iPS cells into spermatogonial stem cells and late-stage male germ cells. We used an approach that combines in vitrodifferentiation and in vivotransplantation. Embryoid bodies （EBs） were obtained from iPS cells using leukaemia inhibitor factor （LIF）-free medium. Quantitative PCR revealed a decrease in Oct4 expression and an increase in StraSand Vasa mRNA in the EBs derived from iPS cells, iPS cell-derived EBs were induced by retinoic acid to differentiate into spermatogonial stem cells （SSCs）, as evidenced by their expression of VASA, as well as CDH1 and GFRal, which are markers of SSCs. Furthermore, these germ cells derived from iPS cells were transplanted into recipient testes of mice that had been pre-treated with busulfan. Notably, iPS cell-derived SSCs were able to differentiate into male germ cells ranging from spermatogonia to round spermatids, as shown by VASA and SCP3 expression. This study demonstrates that iPS cells have the potential to differentiate into late-stage male germ cells. The derivation of male germ cells from iPS cells has potential applications in the treatment of male infertility and provides a model for uncovering the molecular mechanisms underlying male germ cell development.

(-)-Epigallocatechin-3-gallate enhances poly I:C-induced interferon-λ1 production and inhibits hepatitis C virus replication in hepatocytes

AIM To investigate the effect of(-)-epigallocatechin-3-gallate(EGCG) on polyinosinic-polycytidylic acid(poly I:C)-triggered intracellular innate immunity against hepatitis C virus(HCV) in hepatocytes. METHODS A cell culture model of HCV infection was generated by infecting a hepatoma cell line, Huh7, with HCV JFH-1 strain(JFH-1-Huh7). Poly I:C with a high molecular weight and EGCG were used to stimulate the JFH-1-Huh7 cells. Real-time reverse transcription-polymerase chain reaction was used to detect the expression levels of intracellular m RNAs and of intracellular and extracellular HCV RNA. Enzyme-linked immunosorbent assay was used to evaluate the interferon(IFN)-λ1 protein level in the cell culture supernatant. Immunostaining was used to examine HCV core protein expression in Huh7 cells.RESULTS Our recent study showed that HCV replication could impair poly I:C-triggered intracellular innate immune responses in hepatocytes. In the current study, we showed that EGCG treatment significantly increased the poly I:C-induced expression of Toll-like receptor 3(TLR3), retinoic acid-inducible gene I, and IFN-λ1 in JFH-1-Huh7 cells. In addition, supplementation with EGCG increased the poly I:C-mediated antiviral activity in JFH-1-Huh7 cells at the intracellular and extracellular HCV RNA and protein levels. Further investigation of the mechanisms showed that EGCG treatment significantly enhanced the poly I:C-induced expression of IFN-regulatory factor 9 and several antiviral IFNstimulated genes, including ISG15, ISG56, myxovirus resistance A, and 2'-5'-oligoadenylate synthetase 1, which encode the key antiviral elements in the IFN signaling pathway. CONCLUSION Our observations provide experimental evidence that EGCG has the ability to enhance poly I:C-induced intracellular antiviral innate immunity against HCV replication in hepatocytes.

EXPERIMENTAL STUDY ON DIMETHYLSULFOXIDEINDUCED DIFFERENTIATION OF HUMAN ESOPHAGEALEPITHELIAL CARCINOMA CELLS

Objective The treatment of solid tumors by means of differentiation induction has not yet beengained such broken - through success as all-trans retinoic acid (ATRA) in acute promyelocytic leukemia (APL).To explore more effective inducers for solid tumor therapy, dimethyl sulfoxide (DMSO) is considered as acandidate. Methods In the present study, DMSO was used as inducer to human esophageal cancer cell lines invitro, in compared with classical inducer ATRA, in terms of morphology, cell cycle, growth inhibition, cytokeratin4 expression, gap junction-mediated dye transfer and tumorigenecity in nude mice. Results DMSO as well asATRA induced differentiation of human esophageal carcinoma cells. However, DMSO was confirmed to be moreeffective for induced differentiation of esophageal carcinoma cells than ATRA. Conclusion The results suggestedthat DMSO might have a good prospect in the treatment of solid tumors.

全反式维A酸可促进肿瘤相关诱导配体对多种胰腺癌细胞的凋亡作用

目的:观察全反式维A酸(all-trans retinoic acid,ATRA)是否能促进肿瘤坏死因子相关凋亡诱导配体(tumor necrosis factor related apoptosis induced ligand,TRAIL)对多种胰腺癌细胞的凋亡作用。方法:将携带TRAIL基因的pCA13质粒分别转染SW1990、Patu8988和Bx-PC3等3种胰腺癌细胞,转染24 h后加入ATRA或等体积溶剂。四甲基偶氮唑盐(methyl thiazolyl tetrazolium,MTT)法测定细胞活性,流式细胞仪检测细胞的凋亡率和TRAIL受体R1、R2的表达,末端脱氧核苷酸转移酶(terminal deoxynucleotidyl transferase,TdT)介导的dUTP末端标记法(TdT mediated dUTP nick end labeling,TUNEL)和Hoechst双染色法、透射电镜观察细胞凋亡。结果:转染pCA13/TRAIL质粒后再加入ATRA,细胞生长活性与未加ATRA组相比抑制显著(P<0.05)。流式细胞仪检测发现加入ATRA较未加药组明显促进细胞凋亡(P<0.05)。TUNEL和Hoechst双染色法后透射电镜可观察到细胞凋亡表现。但检测TRAIL-R1、TRAIL-R2的表达发现加入ATRA与未加药组差异无统计学意义(P>0.05)。结论:ATRA可促进TRAIL对多种胰腺癌细胞的凋亡作用,其机制与TRAIL-R1、TRAIL-R2的上调无关。

猪肠道组织RIG-I的表达及其在猪传染性胃肠炎病毒致病机制中作用的初步研究

为探究天然免疫分子维甲酸诱导基因Ⅰ(RIG-I)在猪肠道组织中的表达情况,评价其在猪传染性胃肠炎病毒(TGEV)致病机制中的作用。本研究经原核表达重组RIG-I蛋白(rRIG-1)并采用SDS-PAGE切胶纯化该蛋白,将其免疫大白兔制备兔RIG-I多克隆抗体,采用间接ELISA检测抗体效价。结果显示获得了效价可达1∶64000的兔RIG-I多克隆抗体。利用该抗体经western blot检测SPF猪各肠道组织中RIG-I的表达。结果显示,制备的多克隆抗体可与猪各肠道中的RIG-I反应,且RIG-I在SPF猪空肠中的表达量最高。利用该抗体经western blot检测TGEV感染的ST细胞及猪空肠中RIG-I的表达水平。结果显示,TGEV感染后ST细胞中RIG-I的表达水平极显著高于空白对照细胞(P<0.01);与正常SPF猪空肠相比,TGEV感染的SPF猪空肠组织中RIG-I蛋白的表达水平明显提高。表明TGEV感染后能够刺激细胞内源性及感染猪肠道组织中RIG-I蛋白的表达水平。将本研究构建的重组质粒pCAGGS-RIG-I-flag和RIG-I干扰RNA(siRIG-I)分别转染ST细胞,采用western blot鉴定RIG-I的过表达和敲低效果后,再利用TGEV感染,24 h后采用qPCR检测RIG-I对上述ST细胞中IFN-β转录水平的影响;收集细胞上清,采用TCID50方法测定病毒滴度。qPCR及病毒滴度的测定结果显示,与转染空载体的对照组相比,RIG-I过表达的ST细胞中IFN-β的转录水平极显著升高(P<0.001),且细胞上清中的病毒滴度下降约75%;与转染NCsiRNA的对照组相比,敲低RIG-I的ST细胞中IFN-β的转录水平极显著下降(P<0.001),且细胞上清中的病毒滴度升高约4.8倍。表明,TGEV感染细胞中的RIG-I能够促进细胞中IFN-β的转录,提高宿主细胞的抗病毒免疫反应,从而抑制病毒的复制。本研究结果证实RIG-I在介导TGEV诱导宿主细胞产生IFN的过程中发挥重要作用,该结果为深入探究TGEV的致病机制奠定了实验基础。

蓝光对豚鼠离焦性近视进展的抑制作用及其视锥细胞密度变化机制

目的观察蓝光干预对光学离焦性近视豚鼠屈光发育的影响及其作用机制。方法选取普通级2周龄三色豚鼠48只,采用抛硬币法随机分成蓝光组和白光组,每组各24只。所有豚鼠右眼佩戴-5.00 D镜片建立光学离焦模型,为实验眼;左眼为自身对照,不予遮盖。实验前及实验开始后8周,采用带状光检影镜测量豚鼠屈光度,A型超声测量前房深度、晶状体厚度及眼轴长度,角膜曲率计测量角膜曲率半径。实验开始后8周,采用过量麻醉法处死豚鼠,取右眼眼球并分离视网膜,采用视网膜铺片免疫荧光染色观察豚鼠视网膜S及M视锥细胞密度;采用高效液相色谱分析法检测视网膜视黄酸表达;采用实时荧光定量PCR检测视网膜视黄酸受体(RAR-β)和巩膜中基质金属蛋白酶2(MMP-2)、组织金属蛋白酶抑制剂2(TIMP-2)及Ⅰ型胶原的表达;采用苏木精-伊红染色观察巩膜厚度变化。结果实验开始后8周,蓝光组实验眼较白光组实验眼出现(0.63±0.12)D相对远视,眼轴增长延缓(0.08±0.00)mm;蓝光组对照眼较白光组对照眼出现(0.42±0.09)D相对远视,眼轴增长延缓(0.08±0.00)mm;蓝光组实验眼较蓝光组对照眼近视加深(1.52±0.09)D,眼轴增长(0.06±0.00)mm;白光组实验眼较白光组对照眼近视加深(1.66±0.07)D,眼轴增长(0.13±0.00)mm,差异均有统计学意义(均P<0.05)。蓝光组豚鼠视网膜背侧和腹侧M视锥细胞密度小于白光组,背侧和腹侧S视锥细胞密度大于白光组,差异均有统计学意义(t=32.33、52.23、42.09、25.02,均P<0.05)。蓝光干预后近视延缓与腹侧S视锥细胞密度增加呈强正相关(r=0.95,P<0.01)。蓝光组视黄酸含量、RAR-β和MMP-2相对表达量较白光组减少,TIMP-2和Ⅰ型胶原相对表达量较白光组增加,差异均有统计学意义(t=18.73、7.45、3.72、6.19、9.03,均P<0.05)。蓝光组巩膜厚度为(125.0±7.8)μm,较白光组的(102.0±6.3)μm明显增厚,差异有统计学意义(t=26.93,P<0.05)。结论蓝光可抑制豚鼠离焦性近视进展;豚鼠屈光度的改变可能通过视网膜视锥细胞密度变化影响视网膜视黄酸及巩膜胶原的表达来实现。

宽体金线蛭提取物对HEK293细胞维甲酸诱导基因蛋白样受体(RLRs)通路的影响

维甲酸诱导基因蛋白样受体(RLRs)信号通路是机体重要的抗病毒作用途径。宽体金线蛭体内含有抗凝血的活性物质,主要用于治疗血栓等疾病,但对于该信号通路的影响尚无任何报道。本试验目的是采用聚肌苷酸聚胞苷酸(Poly I∶C)建立HEK293细胞RLRs信号通路激活模型,在此基础上揭示宽体金线蛭提取物(LE)对HEK293细胞RLRs信号通路的影响。试验首先转染3个不同质量浓度(1、2、4μg·mL^(-1))的Poly I∶C至HEK293细胞,并分别处理12 h、24 h和48 h,以维甲酸诱导基因I(RIG-I)的蛋白表达水平和mRNA转录水平为RLRs通路激活的指标。RLRs信号通路激活之后,采用LE对HEK293细胞进行处理,共设置4组,每组3个重复,分别为:对照组、2μg·mL^(-1) Poly I∶C转染组、2μg·mL^(-1) Poly I∶C转染且添加150μg·mL^(-1)的水蛭提取物、2μg·mL^(-1) Poly I∶C转染且添加300μg·mL^(-1)的水蛭提取物。处理时长分别为24 h和48 h。试验结果表明,转染3个剂量的Poly I∶C在3个处理时长均引起细胞活力降低,2μg·mL^(-1)和4μg·mL^(-1) Poly I∶C转染HEK293细胞12 h、24 h和48 h均显著提高了RIG-I蛋白的表达量,4μg·mL^(-1)的Poly I∶C转染组RIG-I mRNA转录水平在24 h和48 h显著提高。选择Poly I∶C质量浓度2μg·mL^(-1),处理24 h和48 h作为后续试验激活RLRs的处理条件。质量浓度为150μg·mL^(-1) LE可以显著抑制Poly I∶C介导的细胞活力降低;300μg·mL^(-1)的LE显著降低了RIG-I的蛋白水平;150μg·mL^(-1)和300μg·mL^(-1) LE处理24 h和48 h后均显著抑制了β干扰素的mRNA转录和生成。据此得出如下结论:Poly I∶C转染HEK293细胞成功地激活了RLRs信号通路,宽体金线蛭提取物具有促进HEK293细胞活力和抑制β干扰素生成的作用。

RIG-I/NF-κB信号通路在老龄小鼠围术期神经认知障碍中的作用

目的探讨RIG-I/NF-κB信号通路在老龄小鼠围术期神经认知障碍(perioperative neurocognitive disorders,PND)发生中的作用。方法健康雄性15月龄野生型C57BL/6J小鼠36只,随机分为空白组(C组)、假手术组(Sham组)、PND组和RIG-I^(-/-)+PND组,每组9只。PND组和RIG-I^(-/-)+PND组通过胫骨骨折髓内钉内固定手术构建老龄小鼠术后认知功能障碍模型,RIG-I^(-/-)+PND组海马注射RIG-I-siRNA干扰海马RIG-I的表达。C组不做任何处理,Sham组仅麻醉后切开小腿皮肤,不做胫骨骨折处理。术后第1、3、7天分别通过Morris水迷宫行为学实验评估各组的学习记忆能力、采用RT-qPCR法检测海马组织中RIG-I基因表达,Western blot检测RIG-I和NF-κB(p65)蛋白含量,ELISA法测定海马组织中促炎因子白细胞介素1β(interleukin 1β,IL-1β)、白细胞介素6(interleukin 6,IL-6)及肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平。结果与Sham组相比,PND组小鼠在水迷宫训练潜伏期延长(P<0.001),目标象限停留时间与穿越平台次数均减少(P均<0.05)。而RIG-I^(-/-)+PND组小鼠与PND小鼠相比,潜伏期缩短(P<0.001),目标象限停留时间和穿越平台次数均增加(P均<0.05)。相比PND小鼠,RIG-I^(-/-)+PND组小鼠RIG-I基因表达受到抑制(P<0.001)、RIG-I/NF-κB信号通路中RIG-I和NF-κB p65蛋白表达均减少(P均<0.05)、海马中促炎因子IL-6、TNF-α和IL-1β浓度均降低(P均<0.05)。结论在老龄小鼠中,RIG-I基因沉默可以通过抑制RIG-I/NF-κB信号通路激活,降低神经炎症水平,从而改善手术麻醉引起的神经认知功能障碍。

上调RAI2表达抑制人子宫内膜癌细胞系HEC-1-A和KLE迁移与侵袭

目的检测上调维甲酸诱导基因2(retinoic acid-induced 2,RAI2)表达对子宫内膜癌细胞系迁移、侵袭能力的影响。方法选取子宫内膜癌细胞系HEC-1-A和KLE为研究对象,划痕实验、Transwell小室实验检测细胞迁移、侵袭能力。免疫荧光实验、Western blot检测RAI2、E-cadherin、vimentin的蛋白表达。结果子宫内膜癌细胞系HEC-1-A和KLE中RAI2表达水平上调后,LV-RAI2组子宫内膜癌细胞迁移与侵袭能力减弱(P<0.05),RAI2、E-cadherin表达水平升高,vimentin表达水平降低(P<0.05)。结论上调RAI2表达可能通过上皮间质转化调控抑制子宫内膜癌细胞迁移与侵袭能力。

维甲酸诱导蛋白在消化系统恶性肿瘤中的研究进展

2020年全球癌症统计报告显示,消化系统恶性肿瘤发病率与死亡率均较高,但消化系统恶性肿瘤发生发展机制仍然未明确。维甲酸诱导蛋白(Retinoic acid-induced protein, RAI)是一类由维甲酸诱导的蛋白,与消化系统恶性肿瘤的增殖、侵袭、迁移关系密切,RAI系列蛋白在消化系统肿瘤中的表达水平与临床预后相关,过表达或敲低RAI蛋白可以影响消化系统恶性肿瘤对于靶向药物治疗的敏感性,RAI蛋白可能是消化系统肿瘤发生发展密切相关的特异性靶蛋白。本文就RAI蛋白在消化系统恶性肿瘤发生发展中的作用及相关机制等进行综述,为疾病早期诊断、治疗及预后评估提供一定的参考。