AIM:To investigate the role of hepatopoietin Cn(HPPCn) in apoptosis of hepatocellular carcinoma(HCC)cells and its mechanism. METHODS:Two human HCC cell lines,SMMC7721 and HepG2,were used in this study.Immunostaining, ...AIM:To investigate the role of hepatopoietin Cn(HPPCn) in apoptosis of hepatocellular carcinoma(HCC)cells and its mechanism. METHODS:Two human HCC cell lines,SMMC7721 and HepG2,were used in this study.Immunostaining, Western blotting and enzyme linked immunosorbent assay were conducted to identify the expression of HPPCn and the existence of an autocrine loop of HPPCn/ HPPCn receptor in SMMC7721 and HepG2.Apoptotic cells were detected using fluorescein isothiocyanate (FITC)-conjugated Annexin V and propidium iodide.RESULTS:The HPPCn was highly expressed in human HCC cells and secreted into culture medium(CM). FITC-labeled recombinant human protein(rhHPPCn) could specifically bind to its receptor on HepaG2 cells. Treatment with 400 ng/mL rhHPPCn dramatically increased the viability of HCC-derived cells from 48.1% and 36.9%to 85.6%and 88.4%,respectively(P< 0.05).HPPCn silenced by small-interfering RNA reduced the expression and secretion of HPPCn and increased the apoptosis induced by trichostatin A.Additionally, HPPCn could up-regulate the expression of myeloid cell leukemia-1(Mcl-1)in HCC cells via mitogen-activated protein kinase(MAPK)and sphingosine kinase-1. CONCLUSION:HPPCn is a novel hepatic growth factor that can be secreted to CM and suppresses apoptosis of HCC cells by up-regulating Mcl-1 expression.展开更多
In vertebrates, early brain development takes place at the expanded anterior end of the neural tube, which is filled with embryonic cerebrospinal fluid (E-CSF). We have recently identified a transient blood–CSF barri...In vertebrates, early brain development takes place at the expanded anterior end of the neural tube, which is filled with embryonic cerebrospinal fluid (E-CSF). We have recently identified a transient blood–CSF barrier that forms between embryonic days E3 and E4 in chick embryos and that is responsible for the transport of proteins and control of E-CSF homeostasis, including osmolarity. Here we examined the presence of glucose transporter GLUT-1 as well the presence of caveolae-structural protein Caveolin1 (CAV-1) in the embryonic blood-CSF barrier which may be involved in the transport of glucose and of proteins, water and ions respectively across the neuroectoderm. In this paper we demonstrate the presence of GLUT-1 and CAV-1 in endothelial cells of blood vessels as well as in adjacent neuroectodermal cells, located in the embryonic blood–CSF barrier. In blood vessels, these proteins were detected as early as E4 in chick embryos and E12.7 in rat embryos, i.e. the point at which the embryonic blood–CSF barrier acquires this function. In the neuroectoderm of the embryonic blood-CSF barrier, GLUT-1 was also detected at E4 and E12.7 respectively, and CAV-1 was detected shortly thereafter in both experimental models. These experiments contribute to delineating the extent to which the blood–CSF embryonic barrier controls E-CSF composition and homeostasis during early stages of brain development in avians and mammals. Our results suggest the regulation of glucose transport to the E-CSF by means of GLUT-1 and also suggest a mechanism by which proteins are transported via transcellular routes across the neuroectoderm, thus reinforcing the crucial role of E-CSF in brain development.展开更多
Adult T-cell leukemia( ATL) is a mature T-cell malignancy caused by human T-cell leukemia virus type I infection, and 10%-25% of patients show central nervous system( CNS) involvement. CNS involvement significantly re...Adult T-cell leukemia( ATL) is a mature T-cell malignancy caused by human T-cell leukemia virus type I infection, and 10%-25% of patients show central nervous system( CNS) involvement. CNS involvement significantly reduces survival and there are no effective treatments for CNS involvement. Therefore, an appropriate animal model is required to evaluate the inhibitory effects of novel drugs on the progression of ATL with CNS involvement. Here, we established a mouse model of ATL with CNS involvement using NOD.Cg-Prkdc~ (scid) Il2 rg ^(tm1Wjl)/SzJ mice inoculated with ATL cells intramuscularly in the postauricular region, and these mice showed paraparesis. Of the 10 mice inoculated with ATL cells intramuscularly(I.M.) at 5 weeks of age, 8(80%) showed paraparesis, whereas none of the 10 mice inoculated with ATL cells subcutaneously(S.C.) showed paraparesis. In the I.M. group, PCR detected HTLV-1-specific genes in the thoracic and lumbar vertebrae; however, in the S.C. group, the vertebrae were negative for HTLV-1 genes. Histological analysis revealed a particularly high incidence of tumors, characterized by accumulation of the injected cells, in the thoracic vertebrae of mice in the I.M. group. Tumor cell infiltration was relatively high in the bone marrow. Spinal cord compression caused by invasion of the tumor mass outside the pia mater was observed in the thoracic vertebrae of the spinal cord. In conclusion, we have reported a mouse model of tumor growth with paraparesis that may be used to assess novel therapeutic agents for ATL with CNS involvement.展开更多
基金Supported by(in part)Grants From the National Natural Science Foundation of China,No.30800558 and No.30930041the Chinese Major Special Science&Technology Project for Development of Major New Drugs,No.2009ZX09103-617
文摘AIM:To investigate the role of hepatopoietin Cn(HPPCn) in apoptosis of hepatocellular carcinoma(HCC)cells and its mechanism. METHODS:Two human HCC cell lines,SMMC7721 and HepG2,were used in this study.Immunostaining, Western blotting and enzyme linked immunosorbent assay were conducted to identify the expression of HPPCn and the existence of an autocrine loop of HPPCn/ HPPCn receptor in SMMC7721 and HepG2.Apoptotic cells were detected using fluorescein isothiocyanate (FITC)-conjugated Annexin V and propidium iodide.RESULTS:The HPPCn was highly expressed in human HCC cells and secreted into culture medium(CM). FITC-labeled recombinant human protein(rhHPPCn) could specifically bind to its receptor on HepaG2 cells. Treatment with 400 ng/mL rhHPPCn dramatically increased the viability of HCC-derived cells from 48.1% and 36.9%to 85.6%and 88.4%,respectively(P< 0.05).HPPCn silenced by small-interfering RNA reduced the expression and secretion of HPPCn and increased the apoptosis induced by trichostatin A.Additionally, HPPCn could up-regulate the expression of myeloid cell leukemia-1(Mcl-1)in HCC cells via mitogen-activated protein kinase(MAPK)and sphingosine kinase-1. CONCLUSION:HPPCn is a novel hepatic growth factor that can be secreted to CM and suppresses apoptosis of HCC cells by up-regulating Mcl-1 expression.
文摘目的 :采用同位素相对标记和绝对定量(isobaric tags for relative and absolute quantitation,iTRAQi)技术分析耳蜗核(cochlear nucleus,CN)区域特异性膜蛋白。方法 :出生60 d的雄性SD大鼠分为4组,分别是CN、下丘(inferior colliculus,IC)、上橄榄核(superior oliver complex,SOC)、大脑其余部位(Rest)。提取这4个部位组织的细胞膜蛋白,再采用iTRAQi技术检测出CN区域特异性蛋白。通过Uniprot检索这些蛋白的功能和参与的生物代谢过程。结果:本实验最终得到17种CN区域特异性膜蛋白。对CN区域蛋白进行基因本体(gene ontology,GO)分析发现,这些蛋白主要参与生物调节与发育。UNIPROT检索发现3种蛋白与神经系统功能相关,即半乳糖凝集素-1(galectin-1,Gal-1)、膜联蛋白A2(annexin-A2,AXNA2)和外周蛋白(peripherin,PRPH)。Gal-1与神经生长发育相关;AXNA2参与多种生物调节过程;PRPH与神经退行性病变相关。其中,Gal-1可促进轴突生长、调节突触可塑性且具有神经保护作用;AXNA2可能参与了神经递质释放过程,且有神经营养作用;PRPH在高表达时具有神经毒性,和神经丝蛋白共同参与神经退行性病变。结论:Gal-1、ANXA2和PRPH在耳蜗核中高度表达,可能与中枢信息处理相关,这为进一步研究中枢听觉处理障碍发病机制提供了一定的理论基础。
文摘In vertebrates, early brain development takes place at the expanded anterior end of the neural tube, which is filled with embryonic cerebrospinal fluid (E-CSF). We have recently identified a transient blood–CSF barrier that forms between embryonic days E3 and E4 in chick embryos and that is responsible for the transport of proteins and control of E-CSF homeostasis, including osmolarity. Here we examined the presence of glucose transporter GLUT-1 as well the presence of caveolae-structural protein Caveolin1 (CAV-1) in the embryonic blood-CSF barrier which may be involved in the transport of glucose and of proteins, water and ions respectively across the neuroectoderm. In this paper we demonstrate the presence of GLUT-1 and CAV-1 in endothelial cells of blood vessels as well as in adjacent neuroectodermal cells, located in the embryonic blood–CSF barrier. In blood vessels, these proteins were detected as early as E4 in chick embryos and E12.7 in rat embryos, i.e. the point at which the embryonic blood–CSF barrier acquires this function. In the neuroectoderm of the embryonic blood-CSF barrier, GLUT-1 was also detected at E4 and E12.7 respectively, and CAV-1 was detected shortly thereafter in both experimental models. These experiments contribute to delineating the extent to which the blood–CSF embryonic barrier controls E-CSF composition and homeostasis during early stages of brain development in avians and mammals. Our results suggest the regulation of glucose transport to the E-CSF by means of GLUT-1 and also suggest a mechanism by which proteins are transported via transcellular routes across the neuroectoderm, thus reinforcing the crucial role of E-CSF in brain development.
基金Japan Leukemia Research FundGrant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science,Grant/Award Number:No.24500493
文摘Adult T-cell leukemia( ATL) is a mature T-cell malignancy caused by human T-cell leukemia virus type I infection, and 10%-25% of patients show central nervous system( CNS) involvement. CNS involvement significantly reduces survival and there are no effective treatments for CNS involvement. Therefore, an appropriate animal model is required to evaluate the inhibitory effects of novel drugs on the progression of ATL with CNS involvement. Here, we established a mouse model of ATL with CNS involvement using NOD.Cg-Prkdc~ (scid) Il2 rg ^(tm1Wjl)/SzJ mice inoculated with ATL cells intramuscularly in the postauricular region, and these mice showed paraparesis. Of the 10 mice inoculated with ATL cells intramuscularly(I.M.) at 5 weeks of age, 8(80%) showed paraparesis, whereas none of the 10 mice inoculated with ATL cells subcutaneously(S.C.) showed paraparesis. In the I.M. group, PCR detected HTLV-1-specific genes in the thoracic and lumbar vertebrae; however, in the S.C. group, the vertebrae were negative for HTLV-1 genes. Histological analysis revealed a particularly high incidence of tumors, characterized by accumulation of the injected cells, in the thoracic vertebrae of mice in the I.M. group. Tumor cell infiltration was relatively high in the bone marrow. Spinal cord compression caused by invasion of the tumor mass outside the pia mater was observed in the thoracic vertebrae of the spinal cord. In conclusion, we have reported a mouse model of tumor growth with paraparesis that may be used to assess novel therapeutic agents for ATL with CNS involvement.