载脂蛋白M与高密度脂蛋白代谢及动脉粥样硬化

栽脂蛋白(apo)M是一种新近发现的载脂蛋白,蛋白结构属于Lipocalin超家族成员,它含有一个特征性的疏水结合盒,成熟的apoM保留了具有"疏水锚"作用的信号肽,apoM很可能通过此信号肽锚着在高密度脂蛋白(HDL)磷脂单层.动物实验发现apoM的缺失会导致血浆前β-高密度脂蛋白的消失和异常犬的HDL颗粒的出现.在低密度脂蛋白受体缺陷小鼠,腺病毒致肝脏apoM的过度表达可使动脉粥样硬化病变明显减少.现有研究表明apoM可调节HDL代谢,并具有抗动脉粥样硬化的作用.     

粒细胞集落刺激因子对急性高原MODS心肌保护作用的研究

目的探讨粒细胞集落刺激因子(G-CSF)对高原急性多脏器功能不全综合征(M ODS)大鼠心肌的保护作用。方法在马汉山梯度(海拔3 900 m)建立20只大鼠M ODS模型,观察组(10只)造模前皮下注射G-CSF 10μg/(kg.d),连用5 d;对照组不用药。造模后24 h处死两组大鼠,取心肌标本,测定心肌梗死面积、左心室收缩及舒张期功能、心肌线粒体三磷酸腺苷(ATP)含量及F as mRNA、caspase-3的表达。结果观察组较对照组心肌收缩及舒张期功能增高明显,心肌ATP含量增加,心肌细胞凋亡数量减少,心肌中F as mRNA、caspase-3表达下降,心肌梗死面积缩小。结论G-CSF可提高高海拔地区M ODS大鼠心功能,其机制可能为动员骨髓基质干细胞修复坏死的心肌组织。     

粒细胞集落刺激因子与葛根素治疗急性脑梗死的临床对照研究

目的比较粒细胞集落刺激因子(G-CSF) 与葛根素对急性脑梗死治疗的有效性和安全性,并分析其不同作用机制.方法 63例急性脑梗死病人随机分为3组,分别给予常规西药(对照组)21例、常规西药加用G-CSF(G-CSF组) 21例和常规西药加葛根素(葛根素组)21例,观察治疗前及治疗后14 d时神经功能缺损程度,并随访3个月时临床神经功能及日常生活活动能力.结果 63例均完成了3个月的观察.治疗后14 d时神经功能缺损评分G-CSF组较对照组疗效比较无统计学意义,而葛根素组较对照组疗效间比较有统计学意义,治疗后3个月时神经功能缺损评分G-CSF组和葛根素组较对照组疗效比较均有统计学意义,而G-CSF组和葛根素组疗效比较亦有统计学意义.G-CSF组和葛根素组未出现严重不良反应.结论 G-CSF及葛根素对治疗急性脑梗死安全有效,治疗机制虽有所不同,但G-CSF显示了更好的远期治疗效果.     

辛伐他汀减轻载脂蛋白E~(-/-)小鼠氧化应激及小窝蛋白1的表达

背景氧化应激损伤内皮是动脉粥样硬化的始动因素,他汀对于动脉粥样硬化的干预主要集中在粥样硬化斑块形成之后,而对于粥样硬化斑块形成之前的研究较少。目的观察辛伐他汀对载脂蛋白(apo)E~(-/-)小鼠氧化应激及主动脉内皮小窝蛋白l的影响,探讨辛伐他汀在动脉粥样硬化一级预防中保护内皮功能的机制。方法24只6周龄雄性 apoE~(-/-)小鼠,随机等分为两组:对照组、辛伐他汀[5 mg/(kg·d)]治疗组,4周后处死动物。常规生物化学法测定血总胆固醇(TC)、超氧化物歧化酶活性(SOD)、丙二醛(MDA)和血清一氧化氮(N0)含量。采用苏木素伊红(HE)染色法观察小鼠主动脉内皮组织,免疫组织化学法分析小鼠主动脉内皮的小窝蛋白1的表达。结果两组间血脂水平无显著性差异。辛伐他汀治疗组主动脉内皮组织的损伤减轻(损伤阳性率33.3%比对照组:75%,P<0.05)。治疗4周后,辛伐他汀治疗组 SOD[(135.3±5.5)U/L 比对照组:(97.2±7.6)U/L,P<0.01)和 NO[(28.4±4.1)μmol/L 比对照组:(12.3±2.1)μmol/L,P<0.01]均明显升高,MDA 显著减低[(10.5±...     

辛伐他汀减轻载脂蛋白E-/-小鼠氧化应激及小窝蛋白1的表达

背景 氧化应激损伤内皮是动脉粥样硬化的始动因素.他汀对于动脉粥样硬化的干预主要集中在粥样硬化斑块形成之后,而对于粥样硬化斑块形成之前的研究较少.目的 观察辛伐他汀对载脂蛋白(apo)E-/-小鼠氧化应激及主动脉内皮小窝蛋白1的影响,探讨辛伐他汀在动脉粥样硬化一级预防中保护内皮功能的机制.方法 24只6周龄雄性apoE-/-小鼠.随机等分为两组:对照组、辛伐他汀[5 mg/(kg·d)]治疗组,4周后处死动物.常规生物化学法测定血总胆固醇(TC)、超氧化物歧化酶活性(SOD)、丙二醛(MDA)和血清一氧化氮(NO)含量.采用苏木素伊红(HE)染色法观察小鼠主动脉内皮组织,免疫组织化学法分析小鼠主动脉内皮的小窝蛋白1的表达.结果 两组间血脂水平无显著性差异.辛伐他汀治疗组主动脉内皮组织的损伤减轻(损伤阳性率33.3%比对照组:75%,P<0.05).治疗4周后,辛伐他汀治疗组SOD[(135.35±5.5)U/L比对照组:(97.2±7.6)U/L,P<0.01)和NO[(28.4±4.1)μmol/L比对照组:(12.3±2.1)μmol/L,P<0.01]均明显升高,MDA显著减低[(10.5±0.5)nmol/L比对照组:(17.3±1.0)nmol/L,P<0.01].辛伐他汀治疗组主动脉内皮上小窝蛋白1的表达(表达阳性率41.67%比对照组:83.33%,P<0.05)明显降低.结论 辛伐他汀在不影响血脂水平情况下,抑制主动脉内皮的小窝蛋白l的表达,减轻apoE-/-小鼠氧化应激,增加NO水平,起到改善内皮功能、抗动脉粥样硬化作用,在动脉粥样硬化的一级预防中可能发挥重要作用.     

Apolipoprotein E phenotypes in familial hypercholesterolaemia: importance for expression of disease and response to therapy

Abstract. To study the possible importance of variation at the apolipoprotein (apo) E gene locus for the clinical expression of heterozygous familial hypercholesterolaemia (FH), we determined apo E phenotype and serum lipoprotein pattern in 120 patients with FH. The allele frequency of the patients studies were: ε2 0.033, ε3 0.733, and ε4 0.233. There was no influence of apo E phenotype on the serum concentrations of total, VLDL, LDL or HDL cholesterol, triglycerides, or of apo AI, B or (a). Serum concentrations of apo E were significantly higher in patients with the apo E 3/3 phenotype compared to those with apo E 4/3 or 4/4, and the highest concentrations were found in patients carrying the ε2-allele. The cholesterol-lowering response to therapy with cholestyramine or pravastatin was not related to apo E phenotype. It is concluded that variation at the apo E gene locus is not of major importance for the expression of heterozygous FH.     

Cytokine Combination Therapy with Erythropoietin and Granulocyte Colony Stimulating Factor in a Porcine Model of Acute Myocardial Infarction

Purpose

Erythropoietin (EPO) and granulocyte colony stimulating factor (GCSF) have generated interest as novel therapies after myocardial infarction (MI), but the effect of combination therapy has not been studied in the large animal model. We investigated the impact of prolonged combination therapy with EPO and GCSF on cardiac function, infarct size, and vascular density after MI in a porcine model.

Methods

MI was induced in pigs by a 90 min balloon occlusion of the left anterior descending coronary artery. 16 animals were treated with EPO+GCSF, or saline (control group). Cardiac function was assessed by echocardiography and pressure-volume measurements at baseline, 1 and 6 weeks post-MI. Histopathology was performed 6 weeks post-MI.

Results

At week 6, EPO+GCSF therapy stabilized left ventricular ejection fraction, (41?±?1% vs. 33?±?1%, p?<?0.01) and improved diastolic function compared to the control group. Histopathology revealed increased areas of viable myocardium and vascular density in the EPO+GCSF therapy, compared to the control. Despite these encouraging results, in a historical analysis comparing combination therapy with monotherapy with EPO or GCSF, there were no significant additive benefits in the LVEF and volumes overtime using the combination therapy.

Conclusion

Our findings indicate that EPO+GCSF combination therapy promotes stabilization of cardiac function after acute MI. However, combination therapy does not seem to be superior to monotherapy with either EPO or GCSF.     

Inhibition of S1P Receptor 2 Attenuates Endothelial Dysfunction and Inhibits Atherogenesis in Apolipoprotein E-Deficient Mice

Aim: The bioactive lipid, sphingosine-1-phosphate (S1P), has various roles in the physiology and pathophysiology of many diseases. There are five S1P receptors; however, the role of each S1P receptor in atherogenesis is still obscure. Here we investigated the contribution of S1P receptor 2 (S1P2) to atherogenesis by using a specific S1P2 antagonist, ONO-5430514, in apolipoprotein E-deficient ( Apoe ^−/− ) mice. Methods: Apoe ^−/− mice fed with a western-type diet (WTD) received ONO-5430514 (30 mg/kg/day) or vehicle. To examine the effect on atherogenesis, Sudan IV staining, histological analysis, qPCR, and vascular reactivity assay was performed. Human umbilical vein endothelial cells (HUVEC) were used for in vitro experiments. Results: WTD-fed Apoe ^−/− mice had significantly higher S1P2 expression in the aorta compared with wild-type mice. S1P2 antagonist treatment for 20 weeks reduced atherosclerotic lesion development ( p ＜0.05). S1P2 antagonist treatment for 8 weeks ameliorated endothelial dysfunction ( p ＜0.05) accompanied with significant reduction of lipid deposition, macrophage accumulation, and inflammatory molecule expression in the aorta compared with vehicle. S1P2 antagonist attenuated the phosphorylation of JNK in the abdominal aorta compared with vehicle ( p ＜0.05). In HUVEC, S1P promoted inflammatory molecule expression such as MCP-1 and VCAM-1 ( p ＜0.001), which was attenuated by S1P2 antagonist or a JNK inhibitor ( p ＜0.01). S1P2 antagonist also inhibited S1P-induced JNK phosphorylation in HUVEC ( p ＜0.05). Conclusions: Our results suggested that an S1P2 antagonist attenuates endothelial dysfunction and prevents atherogenesis. S1P2, which promotes inflammatory activation of endothelial cells, might be a therapeutic target for atherosclerosis.     

甜菜碱对载脂蛋白E~(-/-)小鼠动脉粥样硬化发生过程中铜锌超氧化物岐化酶基因甲基化及表达的影响

目的 检测栽脂蛋白E-/-小鼠动脉粥样硬化发生过程中肝脏铜锌超氧化物岐化酶基因启动子区CpG岛甲基化及其表达状态,探讨甜菜碱对动脉粥样硬化的作用及其可能的机刺.方法 将正常的C57BL/6J小鼠作为正常对照组,同品系载脂蛋白E-/-小鼠分为模型组、1%、2%和4%甜菜碱组.用油红O染色法检测小鼠主动脉窦脂质斑块面积,应用甲基化特异性聚合酶链反应检测肝脏钢锌超氧化物岐化酶基因甲基化,荧光定量逆转录聚合酶链反应检测铜锌超氧化物岐化酶mRNA表达,免疫组织化学检测其蛋白表达.结果 饲养至14周,2%和4%甜菜碱组小鼠主动脉窦脂质斑块面积明显少于模型组(P<0.05);各组铜锌超氧化物岐化酶基因CpG岛甲基化状态差异无显著性(P>0.05);各时间段正常对照组铜锌超氧化物岐化酶mBNA表达均高于模型组,7周时1%甜菜碱组mRNA表达高于2%和4%甜菜碱组,14周时1%甜菜碱组mRNA表达高于模型组和2%甜菜碱组;各时间段正常对照组铜锌超氧化物歧化酶蛋白表迭均高于模型组、1%、2%和4%甜菜碱组(P<0.05),但模型组、1%、2%和4%甜菜碱组间无显著性差异.结论 铜锌超氧化物岐化酶基因可能没有参与动脉粥样硬化过程中DNA甲基化的异常改变,补充甜菜碱可以增加肝脏铜锌超氧化物岐化酶mBNA表达,改善载脂蛋白E>-/-小鼠的脂质沉积,减少主动脉窦粥样斑块面积.     

Egr-1 is a Major Vascular Pathogenic Transcription Factor in Atherosclerosis and Restenosis

Reviews in Endocrine and Metabolic Disorders -     

载脂蛋白E基因敲除小鼠动脉粥样硬化斑块中血小板因子4和Toll样受体2的表达

目的观察高脂饲养的载脂蛋白E基因敲除小鼠动脉粥样硬化斑块表达Toll样受体2和血小板因子4的情况,探讨血小板因子4对内皮细胞Toll样受体2表达的影响。方法高脂饲料喂养载脂蛋白E基因敲除小鼠12周,建立动脉粥样硬化模型。安乐死处死动物,原位灌流固定,取主动脉于10%中性缓冲福尔马林中固定,石蜡包埋连续切片,HE染色观察动脉粥样硬化斑块形态,免疫组织化学检测斑块中Toll样受体2和血小板因子4的表达。结果载脂蛋白E基因敲除小鼠血脂水平明显增高,主动脉HE染色可见态动脉粥样硬化病变。在载脂蛋白E基因敲除小鼠主动脉富含脂质斑块中Toll样受体2表达上调,其中血管内皮细胞、巨噬细胞表达Toll样受体2明显增多。载脂蛋白E基因敲除小鼠主动脉斑块中也发现有血小板因子4表达,主要在内皮细胞和动脉粥样硬化斑块肩部。结论1.载脂蛋白E基因敲除小鼠粥样斑块中Toll样受体2表达上调,并且Toll样受体2主要表达在粥样斑块的内皮细胞和巨噬细胞上。2.载脂蛋白E基因敲除小鼠动脉粥样硬化斑块中可见血小板因子4表达。     

Distribution of Apolipoprotein E Isoforms between Very Low and High Density Lipoproteins of Normal Subjects and Hyperlipidemic Patients with Special Reference to Type III Hyperlipidemia

ABSTRACT Serum very low (VLDL) and high density lipoproteins (HDL) from 17 hyperlipidemic patients and 10 normal subjects have been isolated by preparative ultracentrifugation, and the electrophoretic patterns of apolipoprotein E (apo E) isoforms in the lipoproteins have been examined by isoelectric focusing. Type III hyperlipidemia (dyslipoproteinemia) has been suggested to be a disease caused by an abnormal mutant of the apo E-3 isoform. In accordance with this, all patients with type III hyperlipidemia in the present study showed lack of apo E-3 in VLDL. However, all these patients demonstrated a protein zone corresponding to apo E-3 in their HDL fraction. Patients with other types of hyperlipidemia or normal subjects who showed an apo E-4 variant in VLDL had an HDL that lacked apo E-4. The results support the hypothesis that type III hyperlipidemia is due to an abnormal composition of the VLDL particles rather than a result of an abnormal mutant of apo E-3.     

高密度脂蛋白结构、代谢和功能研究新进展

高密度脂蛋白(HDL)主要由载脂蛋白A1(ApoA1)、脂质以及相关的调节因子组成,其结构及功能异常与心血管疾病的发生、发展密切相关。HDL主要通过胆固醇逆向转运途径将血管内皮下巨噬细胞内胆固醇运送至肝脏并排出,调节体内的脂质平衡。研究发现,心血管疾病患者体内HDL的结构及代谢方式发生变化,包括ApoA1的异常修饰、血清淀粉样蛋白A取代ApoA1、HDL运载的miRNA含量变化。本文就HDL的结构、代谢和功能进行综述,为脂质代谢相关疾病的诊断和治疗提供新的思路。     

Granulocyte-Colony Stimulating Factor Administration Ameliorates Liver Regeneration in Animal Model of Fulminant Hepatic Failure and Encephalopathy

It has previously been shown that recombinant granulocyte-colony stimulating factor (rG-CSF) accelerates and enhances hepatocyte proliferation in partially hepatectomized rats. In the present study, we examined the effect of rG-CSF administration on liver injury, regeneration, and survival outcome in an experimental rat model of fulminant hepatic failure (FHF) and encephalopathy induced by repeated injections of thioacetamide (TAA). FHF was induced in adult male Wistar rats by three consecutive intraperitoneal injections of TAA, at intervals of 24 hr. The animals were also injected with either saline or rG-CSF. Serum biochemical parameters and blood ammonia levels, liver histology, stage of hepatic encephalopathy, and survival were statistically significantly improved in TAA-intoxicated and rG-CSF-treated rats compared to TAA-intoxicated and saline-treated ones. Furthermore, rG-CSF not only ameliorated the histologically evident liver injury in a statistically significant manner but also enhanced the proliferative capacity of the hepatocytes. Our data confirm the beneficial effect of rG-CSF administration in this animal model of FHF and encephalopathy, supporting evidence for a possible use of rG-CSF as supportive therapy in the management of FHF.     

Apolipoprotein B/A-I and total cholesterol/high-density lipoprotein cholesterol ratios both predict cardiovascular events in the general population independently of nonlipid risk factors, albuminuria and C-reactive protein

Kappelle PJWH, Gansevoort RT, Hillege JL, Wolffenbuttel BHR, Dullaart RPF on behalf of the PREVEND study group (University Medical Center Groningen and University of Groningen, Groningen, The Netherlands). Apolipoprotein B/A‐I and total cholesterol/high‐density lipoprotein cholesterol ratios both predict cardiovascular events in the general population independently of nonlipid risk factors, albuminuria and C‐reactive protein. J Intern Med 2011; 269 : 232–242. Abstract. Background. The total cholesterol/high‐density lipoprotein cholesterol (TC/HDL‐C) and apolipoprotein (apo) B/A‐I ratios predict major adverse cardiovascular events (MACEs). The extent to which these associations are modified by high‐sensitivity C‐reactive protein (hs‐CRP) and albuminuria is largely unknown. We compared the strength of these ratios with first MACE in the general population and determined whether these associations remain when taking account of these risk markers. Subjects and methods. A prospective case–cohort study was performed among 6948 subjects (PREVEND cohort) without previous cardiovascular disease and who did not use lipid‐lowering drugs initially. Fasting serum TC, low‐density lipoprotein cholesterol (LDL‐C), HDL‐C, non‐HDL‐C, apoB, apoA‐I, triglycerides, hs‐CRP and albuminuria were measured at baseline. The composite endpoint was incident MACE. Results. A total of 362 first cardiovascular events occurred during 7.9 years of follow‐up. All pro‐ and anti‐atherogenic measures of lipoproteins and apos predicted MACEs in age‐ and sex‐adjusted Cox proportional hazard analyses (P = 0.018 to P < 0.001). The age‐ and sex‐adjusted hazard ratio (HR) was 1.37 [95% confidence interval (CI), 1.26–1.48] for the apoB/apoA‐I ratio and 1.24 (95% CI, 1.18–1.29) for the TC/HDL‐C ratio (both P < 0.001). These relationships were essentially unaltered after additional adjustment for triglyceride levels. Pair‐wise comparison revealed that these ratios were of similar importance in age‐ and sex‐adjusted analysis (P = 0.397). The HRs of apoB/apoA‐I (P < 0.001) and TC/HDL‐C (P < 0.001) for risk of MACEs were only marginally attenuated by additional controlling for traditional risk factors (hypertension, diabetes, obesity and smoking), hs‐CRP and albuminuria. Conclusions. First MACE is associated with both the fasting serum apoB/apoA‐I ratio and the TC/HDL‐C ratio in the general population, independently of triglycerides, hs‐CRP and albuminuria.     

载脂蛋白E基因敲除小鼠动脉粥样硬化早期血管外膜血管细胞黏附分子1和细胞间黏附分子1的表达

目的探讨血管外膜血管细胞黏附分子1和细胞间黏附分子1在动脉粥样硬化病灶形成及发展中的作用。方法 6周龄载脂蛋白E基因敲除小鼠和野生型C57BL/6小鼠,高脂饮食喂养2、4和8周,选取升主动脉制备连续切片,部分切片行Movat染色,观察组织形态学变化并测量外膜厚度的变化;部分切片用免疫组织化学法观察不同阶段血管外膜及内膜血管细胞黏附分子1和细胞间黏附分子1表达的动态变化。结果 6周龄载脂蛋白E基因敲除小鼠和各个时间点的C57BL/6小鼠均未观察到内膜损伤的任何迹象,主动脉外膜厚度亦无显著变化,外膜均无血管细胞黏附分子1的表达;高脂喂养2周后,载脂蛋白E基因敲除小鼠血管外膜厚度增加,但在内膜仍无肉眼可见病灶,此时外膜血管细胞黏附分子1呈现弱阳性表达;高脂喂养4周和8周后,载脂蛋白E基因敲除小鼠血管外膜厚度逐渐增加,内膜出现泡沫细胞,纤维斑块,外膜及内膜损伤处血管细胞黏附分子1表达增强。载脂蛋白E基因敲除小鼠随着高脂喂养时间延长,主动脉外膜及内膜细胞间黏附分子1的表达也增加,但C57BL/6小鼠血管外膜细胞间黏附分子1表达量少且稳定,各时间点之间无明显差异。结论载脂蛋白E基因敲除小鼠随着高脂喂养时间延长血管外膜血管细胞黏附分子1和细胞间黏附分子1的表达增加。     

成纤维细胞生长因子与单核-巨噬细胞集落刺激因子融合蛋白在大肠杆菌中的表达

为获得防治动脉粥样硬化和再狭窄的新型基因产品，应用基因工程技术将碱性成纤维细胞生长因子和单核─巨噬细胞集落刺激因子基因克隆到pGEM－3Zf（＋）载体的EcoRI和BamHI位点上，重组成融合基因，亚克隆到pBV220表达载体上，并在大肠杆菌DHα中进行表达，然后用十二烷基磺酸钠─聚丙烯酸胺凝胶电泳和Westernblot进行分析。结果发现，融合蛋白可获得表达，且具有成纤维细胞生长因子与单核─巨噬细胞集落刺激因子的免疫学活性。这为进一步研究该融合蛋白的功能及防治动脉粥样硬化和动脉再狭窄提供一种新的基因产品。     

成纤维细胞生长因子与单核-巨噬细胞集落刺激因子融合蛋白在大肠杆菌中的表达

为获得防治动粥样硬化和再狭窄的新型基因产品，应用基因工程技术将碱性成纤维细胞生长因子和单核－巨噬细胞落刺激因子基因克隆到ｐＧＥＭ－３Ｚｆ（＋）载体的ＥｃｏＲＩ和ＢａｍＨＩ位点上，重组成融合基因，亚克隆到ｐＢＶ２２０表达载体上，并在大肠杆菌ＤＨ中进行表达，然后用十二烷基磺酸钠－聚丙烯酰胺凝胶电泳和Ｗｅｓｔｅｒｎｂｌｏｔ进行分析，结果发现：融合蛋白可获得表达，且具有成纤维细胞生长因子与单核－巨噬细胞凝