The impact of apolipoprotein E(ApoE)isoforms on sporadic Alzheimer's disease has long been studied;however,the influences of apolipoprotein E gene(APOE)on healthy and pathological human brains are not fully unders...The impact of apolipoprotein E(ApoE)isoforms on sporadic Alzheimer's disease has long been studied;however,the influences of apolipoprotein E gene(APOE)on healthy and pathological human brains are not fully understood.ApoE exists as three common isoforms(ApoE2,ApoE3,and ApoE4),which differ in two amino acid residues.Traditionally,ApoE binds cholesterol and phospholipids and ApoE isoforms display diffe rent affinities for their receptors,lipids transport and distribution in the brain and periphery.The role of ApoE in the human depends on ApoE isoforms,brain regions,aging,and neural injury.APOE E4 is the strongest genetic risk factor for sporadic Alzheimer's disease,considering its role in influencing amyloid-beta metabolism.The exact mechanisms by which APOE gene variants may increase or decrease Alzheimer's disease risk are not fully understood,but APOE was also known to affect directly and indirectly tau-mediated neurodegeneration,lipids metabolism,neurovascular unit,and microglial function.Consistent with the biological function of ApoE,ApoE4 isoform significantly alte red signaling pathways associated with cholesterol homeostasis,transport,and myelination.Also,the rare protective APOE variants confirm that ApoE plays an important role in Alzheimer's disease pathogenesis.The objectives of the present mini-review were to describe classical and new roles of various ApoE isoforms in Alzheimer's disease pathophysiology beyond the deposition of amyloid-beta and to establish a functional link between APOE,brain function,and memory,from a molecular to a clinical level.APOE genotype also exerted a heterogeneous effect on clinical Alzheimer's disease phenotype and its outcomes.Not only in learning and memory but also in neuro psychiatric symptoms that occur in a premorbid condition.Cla rifying the relationships between Alzheimer's disease-related pathology with neuropsychiatric symptoms,particularly suicidal ideation in Alzheimer's disease patients,may be useful for elucidating also the underlying pathophysiological process and its prognosis.Also,the effects of anti-amyloid-beta drugs,recently approved for the treatment of Alzheimer's disease,could be influenced by the APOE genotype.展开更多
Apolipoprotein A-IMilano(ApoA-IM)has been shown to significantly reduce coronary atherosclerotic plaques.However,the preparation of cost-effective pharmaceutical formulations of ApoA-IM is limited by the high cost and...Apolipoprotein A-IMilano(ApoA-IM)has been shown to significantly reduce coronary atherosclerotic plaques.However,the preparation of cost-effective pharmaceutical formulations of ApoA-IM is limited by the high cost and difficulty of purifying the protein and producing the highly effective dimeric form.The aim of this study was to create an expression cassette that specifically drives the expression of dimeric ApoA-IM in the protein bodies of rice seeds.The ApoA-IM protein under control of the 13 kDa prolamin promoter is expressed exclusively in its dimeric form within the seeds,and immunocytochemical and immunogold analyses confirmed its expression in different caryopsis tissue such as seed coat,aleurone cell and endosperm,particularly in amyloplast and storage vacuoles.A plant-based ApoA-IM production system offered numerous advantages over current production systems,including the direct production of the most therapeutically effective dimeric ApoA-IM forms,long-term protein storage in seeds,and ease of protein production by simply growing plants.Therefore,seeds had the potential to serve as a costeffective source of therapeutic ApoA-IM.展开更多
Background: Apolipoprotein E2(ApoE2) is a pleiotropic protein that influences several aspects of cancer metabolism and development. Evading apoptosis is a vital factor for facilitating cancer cell growth. However, the...Background: Apolipoprotein E2(ApoE2) is a pleiotropic protein that influences several aspects of cancer metabolism and development. Evading apoptosis is a vital factor for facilitating cancer cell growth. However, the role and mechanism of ApoE2 in regulating cell apoptosis of pancreatic cancer remain unclear. Methods: In this study, we firstly detected the m RNA and protein expressions of ApoE2 in PANC-1 and Capan-2 cells by real-time polymerase chain reaction and Western blotting. We then performed TUNEL and flow cytometric analyses to explore the role of recombinant human ApoE2, p CMV6-ApoE2 and si ApoE2 in the apoptosis of PANC-1 and Capan-2 cells. Furthermore, we investigated the molecular mechanism through which ApoE2 affected apoptosis in PANC-1 cells using immunofluorescence, immunoprecipitation, Western blotting and co-immunoprecipitation analysis. Results: ApoE2 phosphorylated ERK1/2 and inhibited pancreatic cancer cell apoptosis. In addition, our data showed that ApoE2/ERK1/2 altered the expression and mitochondrial localization of BCL-2 via activating CREB. ApoE2/ERK1/2/CREB also increased the total BCL-2/BAX ratio, inhibited the opening of the mitochondrial permeability transition pore and the depolarization of mitochondrial transmembrane potential, blocked the leakage of cytochrome-c and the formation of the apoptosome, and consequently, suppressed mitochondrial apoptosis. Conclusions: ApoE2 regulates the mitochondrial localization and expression of BCL-2 through the activation of the ERK1/2/CREB signaling cascade to evade the mitochondrial apoptosis of pancreatic cancer cells. ApoE2 may be a distinct prognostic marker and a potential therapeutic target for pancreatic cancer.展开更多
Background:Gastric cancer(GC)is a malignancy with the worst prognosis that seriously threatens human health,especially in East Asia.Apolipoprotein C1(apoc1)belongs to the apolipoprotein family.In addition,apoc1 has be...Background:Gastric cancer(GC)is a malignancy with the worst prognosis that seriously threatens human health,especially in East Asia.Apolipoprotein C1(apoc1)belongs to the apolipoprotein family.In addition,apoc1 has been associated with various tumors.However,its role in GC remains unclear.Methods:Firstly,we quantified its expression in GC and adjacent tumor tissues,using The Cancer Genome Atlas(TCGA).Next,we assessed cell invasion and migration abilities.Finally,we revealed the role of apoc1 in the tumor microenvironment(TME),immune cell infiltration and drug sensitivity.Results:Firstly,in TCGA database,it has been shown that elevated expression of apoc1 was identified in various cancers,including GC,then we found that high expression of apoc1 was significantly correlated with poor prognosis in GC.Histologically,apoc1 expression is proportional to grade,cancer stage,and T stage.The experimental results showed that apoc1 promoted cell invasion and migration.Then GO,KEGG,and GSEA pathway analyses indicated that apoc1 may be involved in the WNT pathway and immune regulation.Furthermore,we found out the tumor-infiltrating immune cells related to apoc1 in the tumor microenvironment(TME)using TIMER.Finally,we investigated the correlation between apoc1 expression and drug sensitivity,PD-1 and CTLA-4 therapy.Conclusions:These results suggest that apoc1 participates in the evolution of GC,and may represent a potential target for detection and immunotherapy in GC.展开更多
AIM:To investigate the anti-angiogenic effect of apolipoprotein A1(apoA1)on primary human retinal vascular endothelial cells(HRECs)and explore the possible mechanism.METHODS:The primary HRECs were transfected with apo...AIM:To investigate the anti-angiogenic effect of apolipoprotein A1(apoA1)on primary human retinal vascular endothelial cells(HRECs)and explore the possible mechanism.METHODS:The primary HRECs were transfected with apoA1-GFP recombinant lentiviral and were compared with cells undergoing transfection with empty lentiviral vectors.Hypoxia chambers were used to simulate the anoxic environment of cells under pathological condition.The concentrations of secreted vascular endothelial growth factor(VEGF)and placental growth factor(PlGF)were measured by enzyme-linked immunosorbent assay(ELISA).Cell migration ability was detected by wound healing assay.The sprouting of HRECs was determined by tube formation assay.The protein levels of extracellular signal regulated kinase 1/2(ERK1/2)and phosphor ylated ERK1/2(p-ERK1/2)were measured by Western blot.RESULTS:Overexpressed apoA1 in hypoxia-induced HRECs significantly suppressed PlGF(0.67±0.10 folds,P=0.007).Overexpressed apoA1 also attenuated hypoxiainduced cell migration(0.32±0.11 folds,P<0.0001),tube formation(0.66±0.01 folds,P<0.0001)and the phosphorylation levels of ERK(0.6±0.11 folds,P=0.025).Pretreatment of mitogen-activated protein kinase kinase(MEK)inhibitor(U0126)further reduced the PlGF and angiogenesis in hypoxia-induced HRECs.CONCLUSION:ApoA 1 inhibits the angiogenesis at least in part by inactivating ERK1/2 in hypoxia-induced HRECs.Moreover,apoA1 suppresses the PlGF expression,which selectively associated with pathological angiogenesis.展开更多
At present,ischemic stroke seriously affects people's life and health,and its occurrence,development and therapeutic effect are affected by many factors.With the deep research on ischemic cerebral apoplexy disease...At present,ischemic stroke seriously affects people's life and health,and its occurrence,development and therapeutic effect are affected by many factors.With the deep research on ischemic cerebral apoplexy disease,people have a deeper understanding of its virulence genes.The apolipoprotein E genotype is the research focus recently,its genetic type is not only involved in the occurrence and development of ischemic cerebral apoplexy,but also causes different therapeatic effects.In this paper,we reviewed the relationship between apolipoprotein E gene polymorphism and lipid metabolism and atherosclerosis in ischemic stroke,as well as the differences in the therapeutic effects of thrombolysis,thrombectomy and lipid-lowering among different genotypes.展开更多
In this review, we focus on the pathway of biogenesis of HDL, the essential role of apoA-I, ATP binding cassette transporter A1(ABCA1), and lecithin: cholesterol acyltransferase(LCAT) in the formation of plasma HDL; t...In this review, we focus on the pathway of biogenesis of HDL, the essential role of apoA-I, ATP binding cassette transporter A1(ABCA1), and lecithin: cholesterol acyltransferase(LCAT) in the formation of plasma HDL; the generation of aberrant forms of HDL containing mutant apoA-I forms and the role of apoA-IV and apoE in the formation of distinct HDL subpopulations. The biogenesis of HDL requires functional interactions of the ABCA1 with apoA-I(and to a lesser extent with apoE and apoA-IV) and subsequent interactions of the nascent HDL species thus formed with LCAT. Mutations in apoA-I, ABCA1 and LCAT either prevent or impair the formation of HDL and may also affect the functionality of the HDL species formed. Emphasis is placed on three categories of apoA-I mutations. The first category describes a unique bio-engineered apoA-I mutation that disrupts interactions between apoA-I and ABCA1 and generates aberrant prep HDL subpopulations that cannot be converted efficiently to a subpopulations by LCAT. The second category describes natural and bio-engineered apoA-I mutations that generate preβ and small size a4 HDL subpopulations, and are associated with low plasma HDL levels. These phenotypes can be corrected by excess LCAT. The third category describes bio-engineered apoA-I mutations that induce hypertriglyceridemia that can be corrected by excess lipoprotein lipase and also have defective maturation of HDL.The HDL phenotypes described here may serve in the future for diagnosis, prognoses and potential treatment of abnormalities that affect the biogenesis and functionality of HDL.展开更多
BACKGROUND:Hypertriglyceridemia is an unusual cause of acute pancreatitis and sometimes considered to be an epiphenomenon.This study aimed to investigate the clinical and analytical features and the APOE genotypes in ...BACKGROUND:Hypertriglyceridemia is an unusual cause of acute pancreatitis and sometimes considered to be an epiphenomenon.This study aimed to investigate the clinical and analytical features and the APOE genotypes in patients with acute pancreatitis and severe hypertriglyceridemia.METHODS:We undertook a one-year,prospective study of patients with acute pancreatitis whose first laboratory analysis on admission to the emergency department included measurement of serum triglycerides.The APOE genotype was determined and the patients answered an established questionnaire within the first 24 hours concerning their alcohol consumption,the presence of co-morbidities and any medications being taken.The patients' progression,etiological diagnosis,hospital stay and clinical and radiological severity were all recorded.RESULTS:Hypertriglyceridemia was responsible for 7 of 133 cases of pancreatitis (5%);the remaining cases were of biliary (53%),idiopathic (26%),alcoholic (11%) or other (5%) origin.Compared with these remaining cases,the patients with hypertriglyceridemia were significantly younger,had more relapses,and more often had diabetes mellitus.They usually consumed alcohol or consumed it excessively on the days before admission.Also,the ε4 allele of the APOE gene was more common in this group (P<0.05).CONCLUSION:One of 20 episodes of acute pancreatitis is caused by hypertriglyceridemia and it is linked to genetic (ε4 allele) and comorbid factors such as diabetes and,especially,alcohol consumption.展开更多
AIM:To prospectively investigate the association between the XbaⅠpolymorphisms of apolipoprotein B (APOB)gene and gallstone formation following gastrectomy.METHODS:The study was conducted between January 2005 and Dec...AIM:To prospectively investigate the association between the XbaⅠpolymorphisms of apolipoprotein B (APOB)gene and gallstone formation following gastrectomy.METHODS:The study was conducted between January 2005 and December 2006.A total of 186 gastric cancer patients who had undergone radical gastrectomy were grouped according to XbaⅠpolymorphisms of APOB gene(X+X-group,n=24 and X-X-group,n =162)and compared.The XbaⅠpolymorphisms of APOB gene were detected by polymerase chain reaction-restriction fragment length polymorphism(PCRRFLP).RESULTS:The incidence of gallstone was significantly higher in the X + X-group than in the X-X-group[54.2% vs 9.3%,RR=5.85(2.23-15.32),P<0.001].The serum levels of total cholesterol(TC)and low-density lipoprotein(LDL)were higher in the X + X-than in the X-X-group(4.02±1.12 vs 3.48±0.88,P=0.004 before surgery and 3.88±1.09 vs 3.40±0.86,P=0.008 after surgery).LDL was 2.21±0.96 vs 1.89±0.84(P =0.042)before surgery and 2.09±0.95 vs 1.72±0.85 (P=0.029)after surgery in the two groups.No relationship was found between XbaⅠpolymorphisms and gallbladder motility.CONCLUSION:In Chinese patients after radical gastrectomy,X + allele of APOB gene is another risk factor for the development of gallstone besides the gallbladder motility disorder after surgery.展开更多
Objective We aimed to investigate the cumulative effect of high CRP level and apolipoprotein B-to-apolipoprotein A-1(ApoB/ApoA-1) ratio on the incidence of ischemic stroke(IS) or coronary heart disease(CHD) in a Mongo...Objective We aimed to investigate the cumulative effect of high CRP level and apolipoprotein B-to-apolipoprotein A-1(ApoB/ApoA-1) ratio on the incidence of ischemic stroke(IS) or coronary heart disease(CHD) in a Mongolian population in China.Methods From June 2003 to July 2012,2589 Mongolian participants were followed up for IS and CHD events based on baseline investigation.All the participants were divided into four subgroups according to C-reactive protein(CRP) level and ApoB/ApoA-1 ratio.Cox proportional hazard models were used to estimate the hazard ratios(HRs) and 95% confidence intervals(CIs) for the IS and CHD events in all the subgroups.Results The HRs(95% CI) for IS and CHD were 1.33(0.84-2.12),1.14(0.69-1.88),and 1.91(1.17-3.11) in the ‘low CRP level with high ApoB/ApoA-1',‘high CRP level with low ApoB/ApoA-1',and ‘high CRP level with high ApoB/ApoA-1' subgroups,respectively,in comparison with the ‘low CRP level with low ApoB/ApoA-1' subgroup.The risks of IS and CHD events was highest in the ‘high CRP level with high ApoB/ApoA-1' subgroup,with statistical significance.Conclusion High CRP level with high ApoB/ApoA-1 ratio was associated with the highest risks of IS and CHD in the Mongolian population.This study suggests that the combination of high CRP and ApoB/ApoA-1 ratio may improve the assessment of future risk of developing IS and CHD in the general population.展开更多
AIM:To investigate the relationship between Apolipoprotein C3(APOC3)(-455T>C) polymorphism and nonalcoholic fatty liver disease(NAFLD) in the Southern Chinese han population.METHODS:In this prospective case-control...AIM:To investigate the relationship between Apolipoprotein C3(APOC3)(-455T>C) polymorphism and nonalcoholic fatty liver disease(NAFLD) in the Southern Chinese han population.METHODS:In this prospective case-control study,we recruited 300 NAFLD patients and 300 healthy controls to a cohort representing Southern Chinese han population at The First Affiliated Hospital,Sun Yat-sen University,from January to December 2012. Polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing were used to genotype the APOC3(-455T>C) variants.RESULTS:After adjusting for age,gender,and bodymass index,TC and CC genotypes were found to increase the susceptibility to NAFLD compared to the TT genotype,with adjusted odds ratios(ORs) of 1.77(95%CI:1.16-2.72) and 2.80(95%CI:1.64-4.79),respectively. Further stratification analysis indicated that carriers of the CC genotype was more susceptible to insulin resistance(IR) than those of the TT genotype,with an OR of 3.24(95%CI:1.52-6.92). The CC genotype also was associated with a significantly higher risk of hypertension,hypertriglyceridemia,and low levels of high-density lipoprotein cholesterol(hDL)(P < 0.05). No association was found between the APOC3(-455T>C) polymorphism and obesity,impaired glucose tolerance,hyperuricemia,hypercholesterolemia,or high levels of low-density lipoprotein cholesterol(LDL)(P > 0.05).CONCLUSION:APOC3(-455T>C) genetic variation is involved in the susceptibility to developing NAFLD,IR,hypertension,hypertriglyceridemia,and low hDL in the Southern Chinese han population.展开更多
Immune-driven inflammation plays an important part inatherogenesis and is therefore believed to be key to thedevelopment of cardiovascular disease(CVD), whichis currently the leading cause of death in the Westernworld...Immune-driven inflammation plays an important part inatherogenesis and is therefore believed to be key to thedevelopment of cardiovascular disease(CVD), whichis currently the leading cause of death in the Westernworld. By fulfilling some of the Koch postulates, athero-genesis has even been proposed to be considered as anautoimmune disease, raising the hope that CVD couldbe prevented by immunomodulation. Nevertheless,the role of the immune system and autoimmune reac-tions in atherosclerosis appear to be a double edged-sword, with both pro-atherogenic and anti-atherogenicattributes. Hence, if immunomodulation is to becomea therapeutic option for atherosclerosis and CVD, it willbe crucial to correctly identify patients who might ben-efit from targeted suppression of deleterious autoim-mune responses. This could be achieved, for example, by the detection of disease-associated autoantibodies. In this work, we will review the currently available clini-cal, in vitro, and animal studies dedicated to autoan-tibodies against apolipoprotein A-1(anti-apoA-1 IgG), the major proteic fraction of high density lipoprotein. Current clinical studies indicate that high levels of anti-apoA-1 IgG are associated with a worse cardiovascular prognosis. In addition, in vitro and animal studies indi-cate a pro-inflammatory and pro-atherogenic role, sup-porting the hypothesis that these autoantibodies may play a direct causal role in CVD, and furthermore that they could potentially represent a therapeutic target for CVD in the future.展开更多
AIM To investigate the role of apolipoprotein E (apoE) polymorphism in the lithogenesis of gallstone and the hereditary pathogenesis of the disease.METHODS Polymerase chain reaction (PCR)was used to study apoE phenoty...AIM To investigate the role of apolipoprotein E (apoE) polymorphism in the lithogenesis of gallstone and the hereditary pathogenesis of the disease.METHODS Polymerase chain reaction (PCR)was used to study apoE phenotypes and allelefrequencies in patients with gallstones and control, and the fasting serum lipids of subjectswere also measured by enzymatic methods.RESULTS The levels of triglyceride (TG) andvery low density lipoprotein cholesterol (VLDLC) were much higher in Ez/, patients than that inE,/, control. E,/, patients were accompanied withremarkably low levels of high density lipoproteincholesterol (HDLC) and its subforms. But in E,/#patients there were only slight changes in levelsof VLDLC and low density lipoprotein cholesterol (LDL--C).CONCLUSION Different apoE phenotype patientswith gallstones have different cheracteristics ofdyslipidemia and the average level of serum lipids in patients with gallstones are higher thansubjects without gallstones in the same apoEgene phenotype. EZ allele is possibly one of thedangerous factors in the lithogenesis of cholecystolithiasis.展开更多
AIM: To investigate the effect of high homocysteine(Hcy) levels on apolipoprotein E(apoE) expression and the signaling pathways involved in this gene regulation.METHODS: Reverse transcriptase polymerase chain reaction...AIM: To investigate the effect of high homocysteine(Hcy) levels on apolipoprotein E(apoE) expression and the signaling pathways involved in this gene regulation.METHODS: Reverse transcriptase polymerase chain reaction(RT-PCR) and Western blot were used to assess apo E expression in cells treated with various concentrations(50-500 μmol/L) of Hcy. Calcium phosphatetransient transfections were performed in HEK-293 and RAW 264.7 cells to evaluate the effect of Hcy on apoE regulatory elements [promoter and distal multienhancer 2(ME2)]. To this aim, plasmids containing the proximal apoE promoter [(-500/+73)apoE construct] alone or in the presence of ME2 [ME2/(-500/+73)apoE construct] to drive the expression of the reporter luciferase gene were used. Co-transfection experiments were carried out to investigate the downstream effectors of Hcymediated regulation of apoE promoter by using specific inhibitors or a dominant negative form of IKβ. In other co-transfections, the luciferase reporter was under the control of synthetic promoters containing multiple specific binding sites for nuclear factor kappa B(NF-κB), activator protein-1(AP-1) or nuclear factor of activated T cells(NFAT). Chromatin immunoprecipitation(ChI P)assay was accomplished to detect the binding of NF-κB p65 subunit to the apoE promoter in HEK-293 treated with 500 μmol/L Hcy. As control, cells were incubated with similar concentration of cysteine. NF-κB p65 proteins bound to DNA were immunoprecipitated with anti-p65 antibodies and DNA was identified by PCR using primers amplifying the region-100/+4 of the apoE gene. RESULTS: RT-PCR revealed that high levels of Hcy(250-750 μmol/L) induced a 2-3 fold decrease in apoE m RNA levels in HEK-293 cells, while apo E gene expression was not significantly affected by treatment with lower concentrations of Hcy(100 μmol/L). Immunoblotting data provided additional evidence for the negative role of Hcy in apoE expression. Hcy decreased apoE promoter activity, in the presence or absence of ME2, in a dose dependent manner, in both RAW 264.7 and HEK-293 cells, as revealed by transient transfection experiments. The downstream effectors of the signaling pathways of Hcy were also investigated. The inhibitory effect of Hcy on the apo E promoter activity was counteracted by MAPK/ERK kinase 1/2(MEK1/2) inhibitor U0126, suggesting that MEK1/2 is involved in the downregulation of apoE promoter activity by Hcy. Our data demonstrated that Hcy-induced inhibition of apoE took place through activation of NF-κB. Moreover, we demonstrated that Hcy activated a synthetic promoter containing three NF-κB binding sites, but did not affect promoters containing AP-1 or NFAT binding sites. ChI P experiments revealed that NF-κB p65 subunit is recruited to the apoE promoter following Hcy treatment of cells.CONCLUSION: Hcy-induced stress negatively modulates apoE expression via MEK1/2 and NF-κB activation. The decreased apo E expression in peripheral tissues may aggravate atherosclerosis, neurodegenerative diseases and renal dysfunctions.展开更多
Intracerebral hemorrhage(ICH)is a serious clinical disease with high morbidity,whose pathogenesis might be related to apolipoprotein E(APOE)gene polymorphisms.To comprehensively evaluate the risk factors for ICH occur...Intracerebral hemorrhage(ICH)is a serious clinical disease with high morbidity,whose pathogenesis might be related to apolipoprotein E(APOE)gene polymorphisms.To comprehensively evaluate the risk factors for ICH occurrence,we performed a meta-analysis.We searched online databases to identify eligible studies based on the relationship between APOE genetic polymorphisms and ICH occurrence risk.Specific and pooled odds ratios(ORs)were calculated and by assessing small study bias,we drew the relationship between APOE polymorphisms and ICH risk.We included 15 eligible studies in our study containing a total of 1642 ICH samples and 5545 normal controls.The comparison of e4 andε3 APOE genotypes revealed that specific and pooled ORs showed a significantly increased odds ratio in ICH patients with theε4 genotype,indicating thatε4 gene is a risk factor for ICH occurrence,and the heterogeneity is acceptable.Similarly,it was found that theε2 genotype also contributed to the incidence rate of ICH.However,after the subgroup analysis by ethnicity,this APOE genetic polymorphism acted as a harmful factor only in white populations,but did not show an effect in Asian populations.It was suggested that both 82 andε4 APOE alleles were risk factors for ICH in general.They were risk factors in white populations only,neither had a detectable effect in Asian populations after subgroup analysing by ethnicity.展开更多
Background: Insulin resistance is linked to dyslipidemia, characterized by a decrease in high density lipo-proteins and an increase in low density lipoproteins. Thiazolidinediones (TZDs) are insulin-sensitizing agents...Background: Insulin resistance is linked to dyslipidemia, characterized by a decrease in high density lipo-proteins and an increase in low density lipoproteins. Thiazolidinediones (TZDs) are insulin-sensitizing agents used to improve glycemic control in patients with type 2 diabetes. Recently, the safety of certain TZD regimens has been questioned because of associated adverse effects on the plasma lipid profile. We examined the effect of a TZD, Ciglitazone, on apolipoprotein synthesis and secretion in human liver HepG2 cells. Methods and Results: The effect of Ciglitazone treatment on apolipoprotein synthesis was addressed at the level of transcription, translation and secretion. RT-PCR showed that Ciglitazone increased the transcription of apoE and apoAI but reduced the levels of apoCI and apoB mRNA. Western blot analysis showed an increase in apoAI and apoE secreted in the cell culture media, whereas the amounts of apoB100 and apoCI were reduced. To confirm that Ciglitazone regulates apolipoprotein translation, its effect on de novo protein synthesis was evaluated by metabolic labeling with [35S]-methionine/cysteine, and a similar pattern of regulation was observed. The change in apolipoprotein levels was not secondary to cholesterol biosynthesis or clearance, since Ciglita-zone did not regulate the transcription of HMGCoA reductase, or the LDL receptor. However, mRNA levels for both PPAR-γ and LXRα were induced, suggesting a role for either or both receptors in modulating the hepatic apolipoprotein profile. The involvement of these nuclear receptor transcription factors was confirmed since direct activation of these receptors by endogenous PPAR-γ ligand, 15d-prostaglandin J2, or LXRα ligand, 22(R)hydroxycholesterol, similarly upregulated apoAI and apoE, but down-regulated apoB100 protein synthesis. Conclusion: Our results suggest that Ciglita-zone treatment results in an atheroprotective lipoprotein profile in liver cells. Thus, while the adipose and muscle tissues may be primary targets in TZD-mediated glucose homeostasis, liver PPAR-γ contributes significantly to the regulation of plasma lipoprotein profile.展开更多
Background and objective Apolipoprotein E is a constituent of lipoproteins with considerable variation due to cysteine-arginine exchanges. We investigated the relationship between apo E gene polymorphism and the occur...Background and objective Apolipoprotein E is a constituent of lipoproteins with considerable variation due to cysteine-arginine exchanges. We investigated the relationship between apo E gene polymorphism and the occurrence of coronary artery disease(CAD) in the older population of northern China. Methods The distribution of the HhaI polymorphisms of the apolipoprotein E gene was determined among 55 patients with CAD (CAD group), which was compared with that of 36 elderly subjects without CAD(control group). Results Genotype distributions at both sites (apo E gene 112-bp and 158-bp sites ) were different between the CAD and control groups. The CAD group had lower apolipoprotein E'ε2'frequencies than the control group (P＜0.05). Conclusion Individuals with apolipoprotein E'ε2'are likely to have a reduced risk of developing coronary artery disease as demonstrated by elderly subjects in Northern China.展开更多
AIM:To study the association of apolipoprotein E(APOE) polymorphisms with the susceptibility ofinflammatory bowel disease(IBD) in Saudi patients.METHODS:APOE genotyping was performed to evaluate the allele and genotyp...AIM:To study the association of apolipoprotein E(APOE) polymorphisms with the susceptibility ofinflammatory bowel disease(IBD) in Saudi patients.METHODS:APOE genotyping was performed to evaluate the allele and genotype frequencies in 378 Saudi subjects including IBD patients with ulcerative colitis(n = 84) or Crohn's disease(n = 94) and matched controls(n = 200) using polymerase chain reaction and reverse-hybridization techniques.RESULTS:The frequencies of the APOE ε2 allele and ε2/ε3 and ε2/ε4 genotypes were significantly higher in IBD patients than in controls(P < 0.05),suggesting that the ε2 allele and its heterozygous genotypes may increase the susceptibility to IBD.On the contrary,the frequencies of the ε3 allele and ε3/ε3 genotype were lower in IBD patients as compared to controls,suggesting a protective effect of APOE ε3 for IBD.The prevalence of the ε4 allele was also higher in the patient group compared to controls,suggesting that the ε4 allele may also increase the risk of IBD.Our results also indicated that the APOE ε4 allele was associated with an early age of IBD onset.No effect of gender or type of IBD(familial or sporadic) on the frequency distribution of APOE alleles and genotypes was noticed in this study.CONCLUSION:APOE polymorphism is associated with risk of developing IBD and early age of onset in Saudi patients,though further studies with a large-size population are warranted.展开更多
AIM To characterize the role of apolipoprotein B100(apoB 100) in hepatitis C viral(HCV) infection. METHODS In this study, we utilize a gene editing tool, transcription activator-like effector nucleases(TALENs), to gen...AIM To characterize the role of apolipoprotein B100(apoB 100) in hepatitis C viral(HCV) infection. METHODS In this study, we utilize a gene editing tool, transcription activator-like effector nucleases(TALENs), to generate human hepatoma cells with a stable genetic deletion of APOB to assess of apoB in HCV. Using infectious cell culture-competent HCV, viral pseudoparticles, replicon models, and lipidomic analysis we determined the contribution of apoB to each step of the viral lifecycle. We further studied the effect of mipomersen, an FDAapproved antisense inhibitor of apoB 100, on HCV using in vitro cell-culture competent HCV and determined itsimpact on viral infectivity with the TCID50 method. RESULTS We found that apo B100 is indispensable for HCV infection. Using the JFH-1 fully infectious cell-culture competent virus in Huh 7 hepatoma cells with TALENmediated gene deletion of apoB(APOB KO), we found a significant reduction in HCV RNA and protein levels following infection. Pseudoparticle and replicon models demonstrated that apo B did not play a role in HCV entry or replication. However, the virus produced by APOB KO cells had significantly diminished infectivity as measured by the TCID-50 method compared to wildtype virus. Lipidomic analysis demonstrated that these virions have a fundamentally altered lipidome, with complete depletion of cholesterol esters. We further demonstrate that inhibition of apoB using mipomersen, an FDA-approved anti-sense oligonucleotide, results in a potent anti-HCV effect and significantly reduces the infectivity of the virus. CONCLUSION Apo B is required for the generation of fully infectious HCV virions, and inhibition of apo B with mipomersen blocks HCV. Targeting lipid metabolic pathways to impair viral infectivity represents a novel host targeted strategy to inhibit HCV.展开更多
This review paper focuses on the genetic contribution, in particular, the association of Apolipoprotein E gene polymorphism to lipid abnormality and subsequent acute coronary syndrome in Han Chinese of China. Many res...This review paper focuses on the genetic contribution, in particular, the association of Apolipoprotein E gene polymorphism to lipid abnormality and subsequent acute coronary syndrome in Han Chinese of China. Many researches have been published pertaining the influence of ApoE gene polymorphism on coronary artery disease, dyslipidemia and the response of statin in Han Chinese. Most of the studies in Han Chinese like other populations demonstrated that ApoE 4 allele genetically predisposes coronary artery disease, acute coronary syndrome, severity of occlusion of coronary artery and higher incidence of major adverse cardiovascular events (In Han Chinese, ApoE allele carriers demonstrated 85% increase in major adverse cardiovascular events (MACE) in six months follow up). In addition, ApoE4 allele carrier also showed both increased in LDL level and decrease response to statin therapy in dyslipidemic Han Chinese. On the other hand, ApoE2 carrier is scavenger of cholesterol and triglyceride from the blood;?thus it is cardiovascular-protective. Despite positive relationship between ApoE gene polymorphism and cardiovascular pathologies, prognostic outcome and resistance to intervention, this area of research still requires?extensive investigation in Han Chinese. Because, several other studies revealed either negative effect or showed no effect by ApoE gene polymorphism on cardiovascular disease. Some of the causes of such debatable results could be explained by factors such as diminutive frequency allele and expression of ApoE gene in coronary heart disease. This part of the research yet requires extensive study with bulkier sample size and retrospective in nature, in order to ascertain the influence of ApoE genotype on lipid, anti-hyperlipidemic agent and coronary heart disease. Such studies could assist us to confirm whether to test healthier subjects to predict genetic risk of coronary heart disease in Han Chinese population. The aim of this review paper is to critically analyze the effect of ApoE gene on the occurrence of coronary heart disease in Han Chinese.展开更多
文摘The impact of apolipoprotein E(ApoE)isoforms on sporadic Alzheimer's disease has long been studied;however,the influences of apolipoprotein E gene(APOE)on healthy and pathological human brains are not fully understood.ApoE exists as three common isoforms(ApoE2,ApoE3,and ApoE4),which differ in two amino acid residues.Traditionally,ApoE binds cholesterol and phospholipids and ApoE isoforms display diffe rent affinities for their receptors,lipids transport and distribution in the brain and periphery.The role of ApoE in the human depends on ApoE isoforms,brain regions,aging,and neural injury.APOE E4 is the strongest genetic risk factor for sporadic Alzheimer's disease,considering its role in influencing amyloid-beta metabolism.The exact mechanisms by which APOE gene variants may increase or decrease Alzheimer's disease risk are not fully understood,but APOE was also known to affect directly and indirectly tau-mediated neurodegeneration,lipids metabolism,neurovascular unit,and microglial function.Consistent with the biological function of ApoE,ApoE4 isoform significantly alte red signaling pathways associated with cholesterol homeostasis,transport,and myelination.Also,the rare protective APOE variants confirm that ApoE plays an important role in Alzheimer's disease pathogenesis.The objectives of the present mini-review were to describe classical and new roles of various ApoE isoforms in Alzheimer's disease pathophysiology beyond the deposition of amyloid-beta and to establish a functional link between APOE,brain function,and memory,from a molecular to a clinical level.APOE genotype also exerted a heterogeneous effect on clinical Alzheimer's disease phenotype and its outcomes.Not only in learning and memory but also in neuro psychiatric symptoms that occur in a premorbid condition.Cla rifying the relationships between Alzheimer's disease-related pathology with neuropsychiatric symptoms,particularly suicidal ideation in Alzheimer's disease patients,may be useful for elucidating also the underlying pathophysiological process and its prognosis.Also,the effects of anti-amyloid-beta drugs,recently approved for the treatment of Alzheimer's disease,could be influenced by the APOE genotype.
文摘Apolipoprotein A-IMilano(ApoA-IM)has been shown to significantly reduce coronary atherosclerotic plaques.However,the preparation of cost-effective pharmaceutical formulations of ApoA-IM is limited by the high cost and difficulty of purifying the protein and producing the highly effective dimeric form.The aim of this study was to create an expression cassette that specifically drives the expression of dimeric ApoA-IM in the protein bodies of rice seeds.The ApoA-IM protein under control of the 13 kDa prolamin promoter is expressed exclusively in its dimeric form within the seeds,and immunocytochemical and immunogold analyses confirmed its expression in different caryopsis tissue such as seed coat,aleurone cell and endosperm,particularly in amyloplast and storage vacuoles.A plant-based ApoA-IM production system offered numerous advantages over current production systems,including the direct production of the most therapeutically effective dimeric ApoA-IM forms,long-term protein storage in seeds,and ease of protein production by simply growing plants.Therefore,seeds had the potential to serve as a costeffective source of therapeutic ApoA-IM.
基金supported by grants from the National Natural Science Foundation of China (31370861)the Tianjin Basic Re-search Plan Project (13JCZDJC31300)。
文摘Background: Apolipoprotein E2(ApoE2) is a pleiotropic protein that influences several aspects of cancer metabolism and development. Evading apoptosis is a vital factor for facilitating cancer cell growth. However, the role and mechanism of ApoE2 in regulating cell apoptosis of pancreatic cancer remain unclear. Methods: In this study, we firstly detected the m RNA and protein expressions of ApoE2 in PANC-1 and Capan-2 cells by real-time polymerase chain reaction and Western blotting. We then performed TUNEL and flow cytometric analyses to explore the role of recombinant human ApoE2, p CMV6-ApoE2 and si ApoE2 in the apoptosis of PANC-1 and Capan-2 cells. Furthermore, we investigated the molecular mechanism through which ApoE2 affected apoptosis in PANC-1 cells using immunofluorescence, immunoprecipitation, Western blotting and co-immunoprecipitation analysis. Results: ApoE2 phosphorylated ERK1/2 and inhibited pancreatic cancer cell apoptosis. In addition, our data showed that ApoE2/ERK1/2 altered the expression and mitochondrial localization of BCL-2 via activating CREB. ApoE2/ERK1/2/CREB also increased the total BCL-2/BAX ratio, inhibited the opening of the mitochondrial permeability transition pore and the depolarization of mitochondrial transmembrane potential, blocked the leakage of cytochrome-c and the formation of the apoptosome, and consequently, suppressed mitochondrial apoptosis. Conclusions: ApoE2 regulates the mitochondrial localization and expression of BCL-2 through the activation of the ERK1/2/CREB signaling cascade to evade the mitochondrial apoptosis of pancreatic cancer cells. ApoE2 may be a distinct prognostic marker and a potential therapeutic target for pancreatic cancer.
基金financed by the National Natural Science Foundation(Grant Number 81874058 to Jianping Zhang).
文摘Background:Gastric cancer(GC)is a malignancy with the worst prognosis that seriously threatens human health,especially in East Asia.Apolipoprotein C1(apoc1)belongs to the apolipoprotein family.In addition,apoc1 has been associated with various tumors.However,its role in GC remains unclear.Methods:Firstly,we quantified its expression in GC and adjacent tumor tissues,using The Cancer Genome Atlas(TCGA).Next,we assessed cell invasion and migration abilities.Finally,we revealed the role of apoc1 in the tumor microenvironment(TME),immune cell infiltration and drug sensitivity.Results:Firstly,in TCGA database,it has been shown that elevated expression of apoc1 was identified in various cancers,including GC,then we found that high expression of apoc1 was significantly correlated with poor prognosis in GC.Histologically,apoc1 expression is proportional to grade,cancer stage,and T stage.The experimental results showed that apoc1 promoted cell invasion and migration.Then GO,KEGG,and GSEA pathway analyses indicated that apoc1 may be involved in the WNT pathway and immune regulation.Furthermore,we found out the tumor-infiltrating immune cells related to apoc1 in the tumor microenvironment(TME)using TIMER.Finally,we investigated the correlation between apoc1 expression and drug sensitivity,PD-1 and CTLA-4 therapy.Conclusions:These results suggest that apoc1 participates in the evolution of GC,and may represent a potential target for detection and immunotherapy in GC.
基金Supported by the National Natural Science Foundation of China(No.81500735,No.81970807)。
文摘AIM:To investigate the anti-angiogenic effect of apolipoprotein A1(apoA1)on primary human retinal vascular endothelial cells(HRECs)and explore the possible mechanism.METHODS:The primary HRECs were transfected with apoA1-GFP recombinant lentiviral and were compared with cells undergoing transfection with empty lentiviral vectors.Hypoxia chambers were used to simulate the anoxic environment of cells under pathological condition.The concentrations of secreted vascular endothelial growth factor(VEGF)and placental growth factor(PlGF)were measured by enzyme-linked immunosorbent assay(ELISA).Cell migration ability was detected by wound healing assay.The sprouting of HRECs was determined by tube formation assay.The protein levels of extracellular signal regulated kinase 1/2(ERK1/2)and phosphor ylated ERK1/2(p-ERK1/2)were measured by Western blot.RESULTS:Overexpressed apoA1 in hypoxia-induced HRECs significantly suppressed PlGF(0.67±0.10 folds,P=0.007).Overexpressed apoA1 also attenuated hypoxiainduced cell migration(0.32±0.11 folds,P<0.0001),tube formation(0.66±0.01 folds,P<0.0001)and the phosphorylation levels of ERK(0.6±0.11 folds,P=0.025).Pretreatment of mitogen-activated protein kinase kinase(MEK)inhibitor(U0126)further reduced the PlGF and angiogenesis in hypoxia-induced HRECs.CONCLUSION:ApoA 1 inhibits the angiogenesis at least in part by inactivating ERK1/2 in hypoxia-induced HRECs.Moreover,apoA1 suppresses the PlGF expression,which selectively associated with pathological angiogenesis.
基金Major Science and Technology Project of Hainan Province(ZDKJ202004)。
文摘At present,ischemic stroke seriously affects people's life and health,and its occurrence,development and therapeutic effect are affected by many factors.With the deep research on ischemic cerebral apoplexy disease,people have a deeper understanding of its virulence genes.The apolipoprotein E genotype is the research focus recently,its genetic type is not only involved in the occurrence and development of ischemic cerebral apoplexy,but also causes different therapeatic effects.In this paper,we reviewed the relationship between apolipoprotein E gene polymorphism and lipid metabolism and atherosclerosis in ischemic stroke,as well as the differences in the therapeutic effects of thrombolysis,thrombectomy and lipid-lowering among different genotypes.
基金supported by National Institute of Health Grant HL-48739 and HL-68216
文摘In this review, we focus on the pathway of biogenesis of HDL, the essential role of apoA-I, ATP binding cassette transporter A1(ABCA1), and lecithin: cholesterol acyltransferase(LCAT) in the formation of plasma HDL; the generation of aberrant forms of HDL containing mutant apoA-I forms and the role of apoA-IV and apoE in the formation of distinct HDL subpopulations. The biogenesis of HDL requires functional interactions of the ABCA1 with apoA-I(and to a lesser extent with apoE and apoA-IV) and subsequent interactions of the nascent HDL species thus formed with LCAT. Mutations in apoA-I, ABCA1 and LCAT either prevent or impair the formation of HDL and may also affect the functionality of the HDL species formed. Emphasis is placed on three categories of apoA-I mutations. The first category describes a unique bio-engineered apoA-I mutation that disrupts interactions between apoA-I and ABCA1 and generates aberrant prep HDL subpopulations that cannot be converted efficiently to a subpopulations by LCAT. The second category describes natural and bio-engineered apoA-I mutations that generate preβ and small size a4 HDL subpopulations, and are associated with low plasma HDL levels. These phenotypes can be corrected by excess LCAT. The third category describes bio-engineered apoA-I mutations that induce hypertriglyceridemia that can be corrected by excess lipoprotein lipase and also have defective maturation of HDL.The HDL phenotypes described here may serve in the future for diagnosis, prognoses and potential treatment of abnormalities that affect the biogenesis and functionality of HDL.
基金supported by a grant from Grupos de Investigacion y Desarrollo Tecnologico de la Junta de Andalucía(Grupo consolidado CTS-159)
文摘BACKGROUND:Hypertriglyceridemia is an unusual cause of acute pancreatitis and sometimes considered to be an epiphenomenon.This study aimed to investigate the clinical and analytical features and the APOE genotypes in patients with acute pancreatitis and severe hypertriglyceridemia.METHODS:We undertook a one-year,prospective study of patients with acute pancreatitis whose first laboratory analysis on admission to the emergency department included measurement of serum triglycerides.The APOE genotype was determined and the patients answered an established questionnaire within the first 24 hours concerning their alcohol consumption,the presence of co-morbidities and any medications being taken.The patients' progression,etiological diagnosis,hospital stay and clinical and radiological severity were all recorded.RESULTS:Hypertriglyceridemia was responsible for 7 of 133 cases of pancreatitis (5%);the remaining cases were of biliary (53%),idiopathic (26%),alcoholic (11%) or other (5%) origin.Compared with these remaining cases,the patients with hypertriglyceridemia were significantly younger,had more relapses,and more often had diabetes mellitus.They usually consumed alcohol or consumed it excessively on the days before admission.Also,the ε4 allele of the APOE gene was more common in this group (P<0.05).CONCLUSION:One of 20 episodes of acute pancreatitis is caused by hypertriglyceridemia and it is linked to genetic (ε4 allele) and comorbid factors such as diabetes and,especially,alcohol consumption.
基金Supported by Zhongshan Hospital,Fudan University,Shanghai,China
文摘AIM:To prospectively investigate the association between the XbaⅠpolymorphisms of apolipoprotein B (APOB)gene and gallstone formation following gastrectomy.METHODS:The study was conducted between January 2005 and December 2006.A total of 186 gastric cancer patients who had undergone radical gastrectomy were grouped according to XbaⅠpolymorphisms of APOB gene(X+X-group,n=24 and X-X-group,n =162)and compared.The XbaⅠpolymorphisms of APOB gene were detected by polymerase chain reaction-restriction fragment length polymorphism(PCRRFLP).RESULTS:The incidence of gallstone was significantly higher in the X + X-group than in the X-X-group[54.2% vs 9.3%,RR=5.85(2.23-15.32),P<0.001].The serum levels of total cholesterol(TC)and low-density lipoprotein(LDL)were higher in the X + X-than in the X-X-group(4.02±1.12 vs 3.48±0.88,P=0.004 before surgery and 3.88±1.09 vs 3.40±0.86,P=0.008 after surgery).LDL was 2.21±0.96 vs 1.89±0.84(P =0.042)before surgery and 2.09±0.95 vs 1.72±0.85 (P=0.029)after surgery in the two groups.No relationship was found between XbaⅠpolymorphisms and gallbladder motility.CONCLUSION:In Chinese patients after radical gastrectomy,X + allele of APOB gene is another risk factor for the development of gallstone besides the gallbladder motility disorder after surgery.
基金supported by the National Natural Science Foundation of China(grant Nos.30972531 and 81320108026)a project of the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Objective We aimed to investigate the cumulative effect of high CRP level and apolipoprotein B-to-apolipoprotein A-1(ApoB/ApoA-1) ratio on the incidence of ischemic stroke(IS) or coronary heart disease(CHD) in a Mongolian population in China.Methods From June 2003 to July 2012,2589 Mongolian participants were followed up for IS and CHD events based on baseline investigation.All the participants were divided into four subgroups according to C-reactive protein(CRP) level and ApoB/ApoA-1 ratio.Cox proportional hazard models were used to estimate the hazard ratios(HRs) and 95% confidence intervals(CIs) for the IS and CHD events in all the subgroups.Results The HRs(95% CI) for IS and CHD were 1.33(0.84-2.12),1.14(0.69-1.88),and 1.91(1.17-3.11) in the ‘low CRP level with high ApoB/ApoA-1',‘high CRP level with low ApoB/ApoA-1',and ‘high CRP level with high ApoB/ApoA-1' subgroups,respectively,in comparison with the ‘low CRP level with low ApoB/ApoA-1' subgroup.The risks of IS and CHD events was highest in the ‘high CRP level with high ApoB/ApoA-1' subgroup,with statistical significance.Conclusion High CRP level with high ApoB/ApoA-1 ratio was associated with the highest risks of IS and CHD in the Mongolian population.This study suggests that the combination of high CRP and ApoB/ApoA-1 ratio may improve the assessment of future risk of developing IS and CHD in the general population.
基金Supported by Natural Scientific Foundation of Guangdong Province,No.S2012040007685Doctoral Program Foundation of Institutions of Higher Education of China,No.20120171120090National Natural Science Foundation of China,No.81301769 and No.81170392
文摘AIM:To investigate the relationship between Apolipoprotein C3(APOC3)(-455T>C) polymorphism and nonalcoholic fatty liver disease(NAFLD) in the Southern Chinese han population.METHODS:In this prospective case-control study,we recruited 300 NAFLD patients and 300 healthy controls to a cohort representing Southern Chinese han population at The First Affiliated Hospital,Sun Yat-sen University,from January to December 2012. Polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing were used to genotype the APOC3(-455T>C) variants.RESULTS:After adjusting for age,gender,and bodymass index,TC and CC genotypes were found to increase the susceptibility to NAFLD compared to the TT genotype,with adjusted odds ratios(ORs) of 1.77(95%CI:1.16-2.72) and 2.80(95%CI:1.64-4.79),respectively. Further stratification analysis indicated that carriers of the CC genotype was more susceptible to insulin resistance(IR) than those of the TT genotype,with an OR of 3.24(95%CI:1.52-6.92). The CC genotype also was associated with a significantly higher risk of hypertension,hypertriglyceridemia,and low levels of high-density lipoprotein cholesterol(hDL)(P < 0.05). No association was found between the APOC3(-455T>C) polymorphism and obesity,impaired glucose tolerance,hyperuricemia,hypercholesterolemia,or high levels of low-density lipoprotein cholesterol(LDL)(P > 0.05).CONCLUSION:APOC3(-455T>C) genetic variation is involved in the susceptibility to developing NAFLD,IR,hypertension,hypertriglyceridemia,and low hDL in the Southern Chinese han population.
基金Supported by Swiss National Science Foundation Grants to Dr.Vuilleumier N No.310030_140736and to Dr.Montecucco F No.32003B_134963/1a grant from the Foundation"Gustave and Simone Prévot"to Dr.Montecucco F
文摘Immune-driven inflammation plays an important part inatherogenesis and is therefore believed to be key to thedevelopment of cardiovascular disease(CVD), whichis currently the leading cause of death in the Westernworld. By fulfilling some of the Koch postulates, athero-genesis has even been proposed to be considered as anautoimmune disease, raising the hope that CVD couldbe prevented by immunomodulation. Nevertheless,the role of the immune system and autoimmune reac-tions in atherosclerosis appear to be a double edged-sword, with both pro-atherogenic and anti-atherogenicattributes. Hence, if immunomodulation is to becomea therapeutic option for atherosclerosis and CVD, it willbe crucial to correctly identify patients who might ben-efit from targeted suppression of deleterious autoim-mune responses. This could be achieved, for example, by the detection of disease-associated autoantibodies. In this work, we will review the currently available clini-cal, in vitro, and animal studies dedicated to autoan-tibodies against apolipoprotein A-1(anti-apoA-1 IgG), the major proteic fraction of high density lipoprotein. Current clinical studies indicate that high levels of anti-apoA-1 IgG are associated with a worse cardiovascular prognosis. In addition, in vitro and animal studies indi-cate a pro-inflammatory and pro-atherogenic role, sup-porting the hypothesis that these autoantibodies may play a direct causal role in CVD, and furthermore that they could potentially represent a therapeutic target for CVD in the future.
基金Project supported by National Natural Science Foundation of China,No.39670709.
文摘AIM To investigate the role of apolipoprotein E (apoE) polymorphism in the lithogenesis of gallstone and the hereditary pathogenesis of the disease.METHODS Polymerase chain reaction (PCR)was used to study apoE phenotypes and allelefrequencies in patients with gallstones and control, and the fasting serum lipids of subjectswere also measured by enzymatic methods.RESULTS The levels of triglyceride (TG) andvery low density lipoprotein cholesterol (VLDLC) were much higher in Ez/, patients than that inE,/, control. E,/, patients were accompanied withremarkably low levels of high density lipoproteincholesterol (HDLC) and its subforms. But in E,/#patients there were only slight changes in levelsof VLDLC and low density lipoprotein cholesterol (LDL--C).CONCLUSION Different apoE phenotype patientswith gallstones have different cheracteristics ofdyslipidemia and the average level of serum lipids in patients with gallstones are higher thansubjects without gallstones in the same apoEgene phenotype. EZ allele is possibly one of thedangerous factors in the lithogenesis of cholecystolithiasis.
基金Supported by The grant of the Romanian National Authority for Scientific Research,National Research Council-Executive Agency for Higher Education,Research,Development and Innovation Funding,No.PN-II-ID-PCE-2011-3-0591(grant awarded to Gafencu AV)the Romanian Academy,and the strategic grant financed by the European Social Found within the Sectorial Operational Program Human Resources Development 2007-2013,No.POSDRU/159/1.5/S/133391(Fenyo IM and Trusca VG)
文摘AIM: To investigate the effect of high homocysteine(Hcy) levels on apolipoprotein E(apoE) expression and the signaling pathways involved in this gene regulation.METHODS: Reverse transcriptase polymerase chain reaction(RT-PCR) and Western blot were used to assess apo E expression in cells treated with various concentrations(50-500 μmol/L) of Hcy. Calcium phosphatetransient transfections were performed in HEK-293 and RAW 264.7 cells to evaluate the effect of Hcy on apoE regulatory elements [promoter and distal multienhancer 2(ME2)]. To this aim, plasmids containing the proximal apoE promoter [(-500/+73)apoE construct] alone or in the presence of ME2 [ME2/(-500/+73)apoE construct] to drive the expression of the reporter luciferase gene were used. Co-transfection experiments were carried out to investigate the downstream effectors of Hcymediated regulation of apoE promoter by using specific inhibitors or a dominant negative form of IKβ. In other co-transfections, the luciferase reporter was under the control of synthetic promoters containing multiple specific binding sites for nuclear factor kappa B(NF-κB), activator protein-1(AP-1) or nuclear factor of activated T cells(NFAT). Chromatin immunoprecipitation(ChI P)assay was accomplished to detect the binding of NF-κB p65 subunit to the apoE promoter in HEK-293 treated with 500 μmol/L Hcy. As control, cells were incubated with similar concentration of cysteine. NF-κB p65 proteins bound to DNA were immunoprecipitated with anti-p65 antibodies and DNA was identified by PCR using primers amplifying the region-100/+4 of the apoE gene. RESULTS: RT-PCR revealed that high levels of Hcy(250-750 μmol/L) induced a 2-3 fold decrease in apoE m RNA levels in HEK-293 cells, while apo E gene expression was not significantly affected by treatment with lower concentrations of Hcy(100 μmol/L). Immunoblotting data provided additional evidence for the negative role of Hcy in apoE expression. Hcy decreased apoE promoter activity, in the presence or absence of ME2, in a dose dependent manner, in both RAW 264.7 and HEK-293 cells, as revealed by transient transfection experiments. The downstream effectors of the signaling pathways of Hcy were also investigated. The inhibitory effect of Hcy on the apo E promoter activity was counteracted by MAPK/ERK kinase 1/2(MEK1/2) inhibitor U0126, suggesting that MEK1/2 is involved in the downregulation of apoE promoter activity by Hcy. Our data demonstrated that Hcy-induced inhibition of apoE took place through activation of NF-κB. Moreover, we demonstrated that Hcy activated a synthetic promoter containing three NF-κB binding sites, but did not affect promoters containing AP-1 or NFAT binding sites. ChI P experiments revealed that NF-κB p65 subunit is recruited to the apoE promoter following Hcy treatment of cells.CONCLUSION: Hcy-induced stress negatively modulates apoE expression via MEK1/2 and NF-κB activation. The decreased apo E expression in peripheral tissues may aggravate atherosclerosis, neurodegenerative diseases and renal dysfunctions.
基金the National Natural Science Foundation of China(No.81471201 and No.81171089).
文摘Intracerebral hemorrhage(ICH)is a serious clinical disease with high morbidity,whose pathogenesis might be related to apolipoprotein E(APOE)gene polymorphisms.To comprehensively evaluate the risk factors for ICH occurrence,we performed a meta-analysis.We searched online databases to identify eligible studies based on the relationship between APOE genetic polymorphisms and ICH occurrence risk.Specific and pooled odds ratios(ORs)were calculated and by assessing small study bias,we drew the relationship between APOE polymorphisms and ICH risk.We included 15 eligible studies in our study containing a total of 1642 ICH samples and 5545 normal controls.The comparison of e4 andε3 APOE genotypes revealed that specific and pooled ORs showed a significantly increased odds ratio in ICH patients with theε4 genotype,indicating thatε4 gene is a risk factor for ICH occurrence,and the heterogeneity is acceptable.Similarly,it was found that theε2 genotype also contributed to the incidence rate of ICH.However,after the subgroup analysis by ethnicity,this APOE genetic polymorphism acted as a harmful factor only in white populations,but did not show an effect in Asian populations.It was suggested that both 82 andε4 APOE alleles were risk factors for ICH in general.They were risk factors in white populations only,neither had a detectable effect in Asian populations after subgroup analysing by ethnicity.
文摘Background: Insulin resistance is linked to dyslipidemia, characterized by a decrease in high density lipo-proteins and an increase in low density lipoproteins. Thiazolidinediones (TZDs) are insulin-sensitizing agents used to improve glycemic control in patients with type 2 diabetes. Recently, the safety of certain TZD regimens has been questioned because of associated adverse effects on the plasma lipid profile. We examined the effect of a TZD, Ciglitazone, on apolipoprotein synthesis and secretion in human liver HepG2 cells. Methods and Results: The effect of Ciglitazone treatment on apolipoprotein synthesis was addressed at the level of transcription, translation and secretion. RT-PCR showed that Ciglitazone increased the transcription of apoE and apoAI but reduced the levels of apoCI and apoB mRNA. Western blot analysis showed an increase in apoAI and apoE secreted in the cell culture media, whereas the amounts of apoB100 and apoCI were reduced. To confirm that Ciglitazone regulates apolipoprotein translation, its effect on de novo protein synthesis was evaluated by metabolic labeling with [35S]-methionine/cysteine, and a similar pattern of regulation was observed. The change in apolipoprotein levels was not secondary to cholesterol biosynthesis or clearance, since Ciglita-zone did not regulate the transcription of HMGCoA reductase, or the LDL receptor. However, mRNA levels for both PPAR-γ and LXRα were induced, suggesting a role for either or both receptors in modulating the hepatic apolipoprotein profile. The involvement of these nuclear receptor transcription factors was confirmed since direct activation of these receptors by endogenous PPAR-γ ligand, 15d-prostaglandin J2, or LXRα ligand, 22(R)hydroxycholesterol, similarly upregulated apoAI and apoE, but down-regulated apoB100 protein synthesis. Conclusion: Our results suggest that Ciglita-zone treatment results in an atheroprotective lipoprotein profile in liver cells. Thus, while the adipose and muscle tissues may be primary targets in TZD-mediated glucose homeostasis, liver PPAR-γ contributes significantly to the regulation of plasma lipoprotein profile.
文摘Background and objective Apolipoprotein E is a constituent of lipoproteins with considerable variation due to cysteine-arginine exchanges. We investigated the relationship between apo E gene polymorphism and the occurrence of coronary artery disease(CAD) in the older population of northern China. Methods The distribution of the HhaI polymorphisms of the apolipoprotein E gene was determined among 55 patients with CAD (CAD group), which was compared with that of 36 elderly subjects without CAD(control group). Results Genotype distributions at both sites (apo E gene 112-bp and 158-bp sites ) were different between the CAD and control groups. The CAD group had lower apolipoprotein E'ε2'frequencies than the control group (P＜0.05). Conclusion Individuals with apolipoprotein E'ε2'are likely to have a reduced risk of developing coronary artery disease as demonstrated by elderly subjects in Northern China.
文摘AIM:To study the association of apolipoprotein E(APOE) polymorphisms with the susceptibility ofinflammatory bowel disease(IBD) in Saudi patients.METHODS:APOE genotyping was performed to evaluate the allele and genotype frequencies in 378 Saudi subjects including IBD patients with ulcerative colitis(n = 84) or Crohn's disease(n = 94) and matched controls(n = 200) using polymerase chain reaction and reverse-hybridization techniques.RESULTS:The frequencies of the APOE ε2 allele and ε2/ε3 and ε2/ε4 genotypes were significantly higher in IBD patients than in controls(P < 0.05),suggesting that the ε2 allele and its heterozygous genotypes may increase the susceptibility to IBD.On the contrary,the frequencies of the ε3 allele and ε3/ε3 genotype were lower in IBD patients as compared to controls,suggesting a protective effect of APOE ε3 for IBD.The prevalence of the ε4 allele was also higher in the patient group compared to controls,suggesting that the ε4 allele may also increase the risk of IBD.Our results also indicated that the APOE ε4 allele was associated with an early age of IBD onset.No effect of gender or type of IBD(familial or sporadic) on the frequency distribution of APOE alleles and genotypes was noticed in this study.CONCLUSION:APOE polymorphism is associated with risk of developing IBD and early age of onset in Saudi patients,though further studies with a large-size population are warranted.
基金Supported by the United States National Institutes of Health(NIH),No.F32-DK097855(to Schaefer EAK),No.T32-DK008191(to Motola DL),No.K08-DK088951(to Peng LF),and No.K24-DK078772(to Chung RT)
文摘AIM To characterize the role of apolipoprotein B100(apoB 100) in hepatitis C viral(HCV) infection. METHODS In this study, we utilize a gene editing tool, transcription activator-like effector nucleases(TALENs), to generate human hepatoma cells with a stable genetic deletion of APOB to assess of apoB in HCV. Using infectious cell culture-competent HCV, viral pseudoparticles, replicon models, and lipidomic analysis we determined the contribution of apoB to each step of the viral lifecycle. We further studied the effect of mipomersen, an FDAapproved antisense inhibitor of apoB 100, on HCV using in vitro cell-culture competent HCV and determined itsimpact on viral infectivity with the TCID50 method. RESULTS We found that apo B100 is indispensable for HCV infection. Using the JFH-1 fully infectious cell-culture competent virus in Huh 7 hepatoma cells with TALENmediated gene deletion of apoB(APOB KO), we found a significant reduction in HCV RNA and protein levels following infection. Pseudoparticle and replicon models demonstrated that apo B did not play a role in HCV entry or replication. However, the virus produced by APOB KO cells had significantly diminished infectivity as measured by the TCID-50 method compared to wildtype virus. Lipidomic analysis demonstrated that these virions have a fundamentally altered lipidome, with complete depletion of cholesterol esters. We further demonstrate that inhibition of apoB using mipomersen, an FDA-approved anti-sense oligonucleotide, results in a potent anti-HCV effect and significantly reduces the infectivity of the virus. CONCLUSION Apo B is required for the generation of fully infectious HCV virions, and inhibition of apo B with mipomersen blocks HCV. Targeting lipid metabolic pathways to impair viral infectivity represents a novel host targeted strategy to inhibit HCV.
文摘This review paper focuses on the genetic contribution, in particular, the association of Apolipoprotein E gene polymorphism to lipid abnormality and subsequent acute coronary syndrome in Han Chinese of China. Many researches have been published pertaining the influence of ApoE gene polymorphism on coronary artery disease, dyslipidemia and the response of statin in Han Chinese. Most of the studies in Han Chinese like other populations demonstrated that ApoE 4 allele genetically predisposes coronary artery disease, acute coronary syndrome, severity of occlusion of coronary artery and higher incidence of major adverse cardiovascular events (In Han Chinese, ApoE allele carriers demonstrated 85% increase in major adverse cardiovascular events (MACE) in six months follow up). In addition, ApoE4 allele carrier also showed both increased in LDL level and decrease response to statin therapy in dyslipidemic Han Chinese. On the other hand, ApoE2 carrier is scavenger of cholesterol and triglyceride from the blood;?thus it is cardiovascular-protective. Despite positive relationship between ApoE gene polymorphism and cardiovascular pathologies, prognostic outcome and resistance to intervention, this area of research still requires?extensive investigation in Han Chinese. Because, several other studies revealed either negative effect or showed no effect by ApoE gene polymorphism on cardiovascular disease. Some of the causes of such debatable results could be explained by factors such as diminutive frequency allele and expression of ApoE gene in coronary heart disease. This part of the research yet requires extensive study with bulkier sample size and retrospective in nature, in order to ascertain the influence of ApoE genotype on lipid, anti-hyperlipidemic agent and coronary heart disease. Such studies could assist us to confirm whether to test healthier subjects to predict genetic risk of coronary heart disease in Han Chinese population. The aim of this review paper is to critically analyze the effect of ApoE gene on the occurrence of coronary heart disease in Han Chinese.
