摘要：
Background and aims: Proprotein convertase subtilisin/kexin 9 (PCSK9) has emerged as a popular target in the development of new cholesterol-lowering drugs and therapeutic interventions for atherosclerosis. PCSK9 could accelerate atherosclerosis through mechanisms beyond the degradation of the hepatic lowdensity lipoprotein receptor. Several clinical studies suggested that PCSK9 is involved in atherosclerotic inflammation. Accordingly, this study aimed to explore the role of PCSK9 in vascular inflammation that promotes atherosclerotic progression. Methods: We examined whether PCSK9 silencing via transduction with the lentivirus-mediated PCSK9 shRNA (LV-PCSK9 shRNA) vector affects the formation of vascular lesions in hyperlipidemia-induced atherosclerosis in apolipoprotein E knockout (apoE KO) mice. In vitro, the effects of PCSK9 on oxLDLinduced macrophages inflammation were investigate using LV-PCSK9 and LV-PCSK9 shRNA for PCSK9 overexpression and PCSK9 silencing. Results: Immunohistochemical analysis showed that PCSK9 expression increased within atherosclerotic plaques in apoE KO mice. These in vivo results showed that the LV-PCSK9 shRNA group of mice developed less aortic atherosclerotic plaques compared with the control group. These lesions also had the reduced number of macrophages and decreased expression of vascular inflammation regulators, such as tumor necrosis factor-alpha, interleukin 1 beta, monocyte chemoattractant protein-1, toll-like receptor 4 and nuclear factor kappa B (NF-kappa B). We further showed that PCSK9 overexpression in macrophages in vitro increased the secretion of oxLDL-induced proinflammatory cytokines. PCSK9 overexpression upregulated TLR4 expression and increased p-I kappa B alpha levels, IkB alpha degradation, and NF-kappa B nuclear translocation in macrophages, but PCSK9 knockdown had the opposite effects in oxLDL-treated macrophages. Conclusions: PCSK9 gene interference could suppress atherosclerosis directly through decreasing vascular inflammation and inhibiting the TLR4/NF-kappa B signaling pathway without affecting plasma cholesterol level in high-fat diet-fed apoE KO mice. PCSK9 may be an inflammatory mediator in the pathogenesis of atherosclerosis. (C) 2017 Elsevier B.V. All rights reserved.
摘要：
Background: AT-rich interactive domain 1A gene (ARID1A) had been reported to act as a tumor suppressor in gastric cancer (GC), and reduced expression of ARID1A is significantly correlated with lymphatic invasion and lymph node metastasis. However, its diagnostic value in GC remains unknown. The aim of this study was to detect the expression of serum ARID1A and investigate its diagnostic value in GC. Methods: ARID1A mRNA and protein expression were assessed in 120 GC serum samples and 70 healthy control samples by quantitative real-time polymerase chain reaction (qRT-PCR) and ELISA, respectively. And the association between ARID1A expression and clinicopathologic parameters was evaluated by Chi-square test. To detect the diagnostic value of serum ARID1A, receiver operating characteristic (ROC) curve were established. Results: The expression of ARID1A was down-regulated in GC serum compared to that in healthy controls both at mRNA and protein level (P < 0.001), and its low expression was closely related to tumor size, tumor grade, depth of invasion and lymph node metastasis. Besides, ARID1A expression in serum were significantly correlated with the expression of CA19-9 (P=-0.612, P < 0.001) and CEA (P=-0.635, P < 0.001) in GC. ROC curve showed the AUC of ARID1A for the diagnosis of GC was 0.846 which was higher than that of CA19-9 (0.626) and carcinoembryonic antigen (CEA) (0.706). Conclusions: ARID1A expression decreases in serum of GC patients, and it can be a useful marker for the diagnosis of GC to distinguish GC patients from noncancerous cohorts.
摘要：
Objective: This paper aims at measurement enhanced effect of oxidized lipoprotien(a) [ox Lp(a)] on permeability of monolayer endothelial cells and relationship with reactive oxygen species(ROS) generation and desmogleins(DSGs) expression.Methods and Results: Transendothelial permeability was assayed by transwell and reactive oxygen species(ROS) was determined by DCFH-DA staining. RT-PCR was carried out to determine DSGl and DSC2 expression in m RNA, respectively.Transendothelial permeability was enhanced by ox LP(a) dose and time dependently. The most marked effect appeared at a concentration of 100 mg/L, Transendothelial permeability reached the maximum value after 2 h of FITC-dextran addition, and then gradually decreased after 4 h. ox Lp(a) induces the generation of cellular reactive oxygen species(ROS), and this effect could be inhibited by superoxide dismutase(SOD).Incubation of HUVECs with ox Lp(a) resulted in a dose and time-dependent down-regulation of DSGl and DSC2 expression at transcriptional level. Conclusion:Permeability of monolayer endothelial cells was enhanced by ox Lp(a) which is related to up-regulating ROS formation and down-regulating desmogleins expression.
摘要：
Low shear stress plays a crucial role in the initiation and progression of atherosclerotic lesions. However, the detailed mechanisms of these processes remain unclear. In this study, the effect of low shear stress on endothelial cell autophagy and its potential mechanism were investigated. Results showed autophagy dysfunction and ten-eleven translocation 2 (TET2) protein downregulation during atherosclerotic lesion progression. Autophagic markers BECLIN 1 and LC3II/LC3I under low shear stress (5 dyne/cm(2)) obviously decreased compared with those under physiological shear stress (15 dyne/cm(2)), whereas autophagic substrate p62 increased. TET2 expression was also downregulated under low shear stress. Endothelial cell autophagy was improved with TET2 overexpression but was impaired by TET2 siRNA treatment. Moreover, TET2 overexpression upregulated the expression of endothelial cell nitric oxide synthase (eNOS) and downregulated the expression of endothelin-1 (ET-1). TET2 siRNA further attenuated eNOS expression and stimulated ET-1 expression. Overall, the results showed that low shear stress downregulated endothelial cell autophagy by impaired TET2 expression, which might contribute to the atherogenic process.
关键词：
Human umbilical cord-derived late endothelial progenitor cells (HUCB-late EPCs);Recombinant adeno-associated virus (rAAV);Transduction efficiency
摘要：
To evaluate the transduction efficiency of human umbilical cord-derived, late endothelial progenitor cells late (HUCB-late EPCs) with nine recombinant adeno-associated virus (rAAV) serotypes and the ability of proliferation and migration of the cells after transduction. rAAV2 and rAAV6 showed a greater ability than other serotypes to transduce late EPCs (P < 0.05). After transduction, cell proliferation ability weakened (P < 0.05), but the ability of migration to stromal cell-derived factor (SDF-1) unchanged. There is an advantage of choosing the optimal rAAV serotype as a gene vector to alter the biologic characteristics of late EPCs.
摘要：
Tet methylcytosine dioxygenase 2 (TET2) mediates the conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). The loss of TET2 is associated with advanced atherosclerotic lesions. Our previous study showed that TET2 improves endothelial cell function by enhancing endothelial cell autophagy. Accordingly, this study determined the role of TET2 in atherosclerosis and potential mechanisms. In ApoE-/- mice fed high-fat diet, TET2 overexpression markedly decreased atherosclerotic lesions with uniformly increased level of 5hmC and decreased level of 5mC in genomic DNA. TET2 overexpression also promoted autophagy and downregulated inflammation factors, such as vascular cell adhesion molecule 1, intercellular adhesion molecule 1, monocyte chemotactic protein 1, and interleukin-1. Consistently, TET2 knockdown with small hairpin RNA (shRNA) in ApoE-/- mice decreased 5hmC and increased 5mC levels in atherosclerotic lesions. Meanwhile, autophagy was inhibited and atherosclerotic lesions progressed with an unstable lesion phenotype characterized by large lipid core, macrophage accumulation, and upregulated inflammation factor expression. Experiments with the cultured endothelial cells revealed that oxidized low-density lipoprotein (ox-LDL) inhibited endothelial cell autophagy. TET2 shRNA strengthened impaired autophagy and autophagic flux in the ox-LDL-treated endothelial cells. TET2 overexpression reversed these effects by decreasing the methylation level of the Beclin 1 promoter, which contributed to the downregulation of inflammation factors. Overall, we identified that TET2 was downregulated during the pathogenesis of atherosclerosis. The downregulation of TET2 promotes the methylation of the Beclin 1 promoter, leading to endothelial cell autophagy, impaired autophagic flux, and inflammatory factor upregulation. Upregulation of TET2 may be a novel therapeutic strategy for treating atherosclerosis.
通讯机构：
[Wang, Zuo] U;Univ South China, Inst Cardiovasc Res, Key Lab Atherosclerol Hunan Prov, Hengyang 421001, Hunan, Peoples R China.
关键词：
Arteriosclerosis;Autophagy;Oxidised lipoprotein(a);Oxygen species
摘要：
Oxidised lipoprotein(a) [oxLp(a)] is considered as a more potent arteriosclerotic factor than native Lp(a). However, the molecular mechanisms underlying this potency remain unclear. Reactive oxygen species (ROS) possibly act as intracellular second messengers that participate in autophagy stimulation. In this study, the effect of oxLp(a) on endothelial cell autophagy was determined. The mechanism and effect of autophagy on endothelial cells were also investigated. Results showed that oxLp(a) could induce autophagy depending on the generation of cellular ROS. Superoxide dismutase, an antioxidant, could inhibit oxLp(a)-induced autophagy in human umbilical vascular endothelial cells. Furthermore, poly(adenosine diphosphate-ribose) polymerase-1 (PARP-1)-liver kinase B1 (LKB1)-adenosine monophosphate-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR) and LKB1-AMPK-mTOR pathways are involved in oxLp(a)-induced autophagy. These pathways are also dependent on ROS. Thus, oxLp(a) induced autophagy via LKB1-AMPK-mTOR and PAPR-1-LKB1-AMPK-mTOR pathways, which are dependent on ROS generation. (C) 2015 Elsevier Ireland Ltd. All rights reserved.
期刊：
MOLECULAR MEDICINE REPORTS,2015年12(3):3599-3606 ISSN：1791-2997
通讯作者：
Yuan, Zhonghua
作者机构：
[Meng, Lei; Tang, Chaoke; Yin, Weidong; Qiao, Yuncheng; Yi, Guanghui; Guo, Dongming; Wang, Zuo; Yuan, Zhonghua] Univ South China, Inst Cardiovasc Dis, Key Lab Arteriosclerol Hunan, Hengyang 421001, Hunan, Peoples R China.;[Qiao, Yuncheng] Pingyu Renmin Hosp, Dept Cardiovasc Med, Pingyu 463400, Henan, Peoples R China.;[Liu, Qingnan] Yiyang Med Coll, Dept Basic Nursing, Yiyang 413000, Hunan, Peoples R China.;[Liu, Xiaohui] Soochow Univ, Cyrus Tang Hematol Ctr Res Partnership, Jiangsu Inst Hematol, Affiliated Hosp 1, Suzhou 215400, Jiangsu, Peoples R China.;[Tian, Guoping] Univ South China, Dept Cardiovasc Med, Affiliated Hosp 2, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Yuan, Zhonghua] U;Univ South China, Inst Cardiovasc Dis, Key Lab Arteriosclerol Hunan, 28 West Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.
关键词：
small interfering RNA;adipophilin;acyl-coenzyme A;cholesterol acyltransferse 1;retrovirus;lipid
摘要：
Oxidized low-density lipoprotein (ox-LDL) can increase the expression of adipophilin and the accumulation of intracellular lipid droplets. However, the detailed mechanisms remain to be fully elucidated. The present study aimed to investigate the mechanism underlying the effect of ox-LDL on the expression of adipophilin and the accumulation of intracellular cholesterol esters. The results revealed that ox-LDL increased the activation of protein kinase C alpha (PKC alpha), expression of adipophilin and acyl-coenzymeA: cholesterol acyltransferse 1 (ACAT1) and increased accumulation of intracellular cholesterol esters. In addition, PKCa siRNA abrogated ox-LDL-induced adipophilin, expression of ATAC1 and accumulation of cholesterol esters. Furthermore, ox-LDL increased the accumulation of intracellular cholesterol esters and expression of ACAT1, and this effect were reversed by transfection with adipophilin siRNA. Taken together, these results demonstrated that ox-LDL induces the accumulation of cholesterol esters, which is mediated by the PKC alpha-adipophilin-ACAT1 pathway.
