亲环素A在巨噬细胞荷脂过程中的影响

目的观察胆固醇转运复合物中关键蛋白亲环素A在氧化型低密度脂蛋白诱导的巨噬细胞荷脂过程中的表达变化及其与细胞内胆固醇蓄积的关系,进而分析亲环素A在巨噬源性泡沫细胞形成过程中的作用。方法采用75 mg/L氧化型低密度脂蛋白与RAW264.7细胞共同孵育,建立巨噬细胞荷脂化模型;Western-blot、免疫荧光法检测亲环素A蛋白的表达水平;高效液相色谱法检测细胞内胆固醇含量的变化。结果75 mg/L氧化型低密度脂蛋白与RAW264.7细胞共同孵育48 h后,亲环素A的蛋白表达逐渐减弱,48 h、72 h分别较未处理组下降了54.5%±6.3%、59.8%±5.9%(P<0.05)。间接免疫荧光定位检测发现氧化型低密度脂蛋白显著抑制RAW264.7细胞中亲环素A在胞膜、胞浆中的表达,且随着处理时间的延长作用更明显。细胞内胆固醇酯/总胆固醇的比值由未处理组的28.3%±1.2%上升至48 h的42.3%±5.9%(P均<0.05)。结论氧化型低密度脂蛋白诱导的RAW264.7巨噬细胞泡沫化过程中,亲环素A的表达下调与细胞胆固醇蓄积密切相关。

亲环素A在巨噬细胞荷脂过程中的表达及普罗布考干预的影响

目的观察亲环素A在氧化型低密度脂蛋白诱导的巨噬细胞荷脂过程中的表达变化及其与细胞内胆固醇蓄积的关系,进而探讨亲环素A在动脉粥样硬化形成中的作用机制。方法采用75 mg/L氧化型低密度脂蛋白与RAW264.7巨噬细胞共同孵育,建立巨噬细胞荷脂化模型,油红O染色观察细胞内脂滴的形成,高效液相色谱法检测细胞内胆固醇含量,Western-blot检测亲环素A的蛋白表达;用75 mg/L普罗布考干预对上述检测的影响。结果氧化型低密度脂蛋白与RAW264.7细胞共同孵育48 h后,油红O染色显示细胞内有大量脂滴形成,细胞内总胆固醇和游离胆固醇含量均明显增加,胆固醇酯/总胆固醇的比值为42.3%±5.9%,符合荷脂细胞特征;亲环素A的蛋白表达明显减弱。予普罗布考处理,细胞内脂滴明显减少,胆固醇酯/总胆固醇的比值降至32.9%±2.5%,亲环素A的蛋白表达增加81.3%±3.6%,较对照组差异有显著性(P均<0.05)。结论氧化型低密度脂蛋白诱导的RAW264.7巨噬细胞荷脂过程中,亲环素A表达下调,促进细胞胆固醇蓄积;普罗布考干预可上调亲环素A蛋白表达,减轻细胞内的胆固醇蓄积。

Procoagulant activity of circulating microparticles is associated with the presence of moderate calcified plaque burden detected by multislice computed tomography

Background Circulating microparticles （MPs） have been reported to be associated with coronary artery disease （CAD）. In this study, we explored the relationship between MPs procoagulant activity and characteristics of atherosclerotic plaque detected by 64-slice computed tomography angiography （CTA）. Methods In 127 consecutive patients with CAD but without acute coronary syndrome and who under went 64-slice CTA, MPs procoagulant activity in plasma Coy a thrombin generation test）, soluble form of lectin-like oxidized low-density lipoprotein receptor-1 （sLOX-1） and N（epsilon）-（carboxymethyl） lysine （CML） circulating levels （by ELISA） were measured. A quantitative volumetric analysis of the lumen and plaque burden of the vessel wall （soft and calcific components）, for the three major coronary vessels, was performed. The patients were classified in three groups according to the presence of calcium volume： non-calcified plaque （NCP） group （calcium volume （%） = 0）, moderate calcified plaque （MCP） group （0 〈 calcium volume （%） 〈 1）, and calcified plaque （CP） group （calcium volume （%） 〉 1）. Results MPs procoagulant activity and CML levels were higher in MCP group than in CP or NCP group （P = 0.009 and P = 0.027, respectively）. MPs procoagulant activity was positively associated with CML （r = 0.317, P 〈 0.0001） and sLOX-1 levels （r = 0.216, P = 0.0025）. Conclusions MPs procoagulant activity was higher in the MCP patient group and correlated positively with sLOX-1 and CML levels, suggesting that it may characterize a state of blood vulnerability that may locally precipitate plaque instability and increase the risk of subsequent major cardiovascular events.

Culture of Scenedesmus acuminatus in Corn Steep Liquor

Microalgae have been evaluated as a source of lipids for biodiesel production. They can be grown on effluent and produce biomass while removing organic and mineral components from the medium. The use of agro-industrial wastes for the production of microalgae is an alternative to reduce the costs related to the composition of the culture medium, thus reducing operational costs considerably. This work was conceived as a research about the cultivation of microalgae Scenedesmus acuminatus on the substrate composed by corn steep liquor. A central composite design （CCD） was carried to study the influence of the effluent and inoculum concentration on the chemical oxygen demand （COD） of the culture. Statistical analysis indicated that the percentage of inoculum and effluent had an influence on the COD. The cultivation, together with the coagulation procedure, was efficient for the removal of organic matter, verified through the COD reduction and changing of pH value. These two parameters reached the appropriate level according to the standard required by current legislation.