丹参酮ⅡA对泡沫细胞胆固醇平衡的影响

目的通过体外细胞实验阐明丹参酮ⅡA对泡沫细胞胆固醇平衡的影响。方法体外培养小鼠RAW264.7细胞,以氧化型低密度脂蛋白诱导为泡沫细胞模型,并用不同浓度的丹参酮ⅡA进行处理,通过油红O染色观察细胞内脂质堆积情况,酶比色法定量检测细胞内总胆固醇和胆固醇酯的变化,荧光定量PCR和WesternBlot检测细胞中CD36、三磷酸腺苷结合盒转运体A1(ABCA1)、肝脏X受体α(LXRα)、过氧化体增殖物激活型受体α(PPARα)及PPARγ的mRNA和蛋白表达。结果 0～20 mg/L的丹参酮ⅡA对泡沫细胞增殖活力无明显影响,20 mg/L丹参酮ⅡA干预后,泡沫细胞内胆固醇酯与总胆固醇的比值显著降低,细胞内脂质累积减少,并上调AB-CA1、LXRα和PPARα的mRNA和蛋白表达,但对CD36表达无明显作用。结论丹参酮ⅡA能抑制泡沫细胞的形成,其机制可能是通过诱导PPARα、LXRα和ABCA1表达,促进胆固醇的外排。     

冠心病患者巨噬细胞胆固醇流出的变化

目的研究冠心病患者血液中单核细胞分化为巨噬细胞并荷脂后胆固醇流出的影响机制。方法分离冠心病患者(试验组)和正常人群(对照组)外周静脉血中单核细胞,并用佛波酯诱导为巨噬细胞,收集分离血清,检测各项血脂指标并备用。细胞用[3H]胆固醇处理24 h使其荷脂,然后分为四组:对照组+正常血清、对照组+高脂血清、试验组+正常血清及试验组+高脂血清。分别检测ABCA1、ABCG1表达及胆固醇流出率。结果与对照组比较,试验组单核/巨噬细胞胆固醇流出能力受损,油红O染色显示细胞内脂质蓄积增加,细胞内胆固醇流出减少,但ABCA1和ABCG1的表达改变不明显。与正常血清比较,试验组及对照组中高脂血清明显影响胆固醇流出能力,细胞内脂质蓄积增加,细胞内胆固醇流出减少,但不影响ABCA1和ABCG1的表达。结论冠心病患者巨噬细胞胆固醇流出能力受损,可能与动脉粥样硬化性血管疾病的发生相关。     

小凹及小凹蛋白1：胆固醇逆向转运与炎症应答的共同分子平台

脂质紊乱和炎症反应在动脉粥样硬化的发生发展中发挥了重要的作用。其中胆固醇的逆向转运能力是决定动脉粥样硬化进程与转归的关键。大量文献及研究结果显示,小凹以及小凹蛋白1既在荷脂细胞胆固醇流出中发挥转运中心和关键分子作用,也在炎症反应中发挥介导抗炎的信号转导作用。因此,小凹以及小凹蛋白1可能是荷脂细胞胆固醇逆向转运和炎症应答的共同分子平台。     

非高密度脂蛋白胆固醇与载脂蛋白B在心血管疾病风险评估中的比较

非高密度脂蛋白胆固醇水平反映致动脉粥样硬化胆固醇总量,载脂蛋白B浓度反应致动脉粥样硬化颗粒总数。近期研究发现非高密度脂蛋白胆固醇和载脂蛋白B的心血管疾病风险预测价值优于传统指标低密度脂蛋白胆固醇。文章就这两个指标的心血管风险评估效能及临床操作性能做一综述。     

肝脏表达Niemann-Pick C1-Like 1调节肝X受体诱导的小鼠胆固醇分泌

目的:探讨小鼠肝脏过表达人NPC1L1对LXR诱导的小鼠胆固醇分泌的影响。方法:给予野生型小鼠(WT)和肝脏过表达人NPC1L1的转基因小鼠(L1Tg)胃饲LXR激动剂(T0901317)7 d后,抽提小鼠粪便总脂质并检测核心甾醇的含量,检测小鼠的血浆脂质水平,分析肝脏ABCG5和ABCG8的mRNA表达水平。结果:L1Tg小鼠与WT小鼠相比,除血浆游离胆固醇含量显著升高外,粪便核心甾醇含量及肝脏ABCG5和G8的mRNA水平差异无统计学意义;在胃饲T0901317 1 w后,WT小鼠的粪便核心甾醇含量由[(3.22±0.44)升高到(28.68±1.05)μmol.d-1.100 g-1],血浆总胆固醇、游离胆固醇、胆固醇酯和磷脂的含量均显著升高,同时肝脏的ABCG5和G8的mRNA水平也分别上调了5倍和2倍;然而,L1Tg小鼠经T0901317处理后,与T0901317处理的WT小鼠相比,粪便核心甾醇的分泌减少了56%,血浆游离胆固醇含量升高了40%,肝脏的ABCG5和G8的mRNA水平分别降低了52.4%和40.6%。结论:肝脏特异表达人NPC1L1降低了LXR诱导的小鼠粪便核心甾醇的分泌,并升高了血浆游离胆固醇水平,可能与下调LXR诱导的肝脏ABCG5和G8 mRNA表述水平有一定关系。     

结直肠癌患者血浆胆固醇水平相关研究

目的 探讨结直肠癌患者手术前后血浆胆固醇水平变化及其与结直肠癌分期的相关性.方法 术前及术后1、3、7d测定临床确诊的结直肠癌患者血浆胆固醇含量,记录相应病例的肿瘤侵润、淋巴结转移及分化情况.并取健康查体者30例做术前对照.结果 结直肠癌患者术前胆固醇水平较对照组显著降低,差异有统计学意义（P＜0.05）,且与临床病理分期有相关性.术后胆固醇水平升高,与术前比较,差异有统计学意义（P＜0.05）.结论 结直肠癌患者术前胆固醇降低,术后升高,并且与临床分期相关,分期越晚,降低越明显.     

Cholesterol Efflux Capacity In Vitro Predicts the Severity and Extent of Coronary Artery Disease in Patients with and without Type 2 Diabetes

Objective - To investigate the relation between severity and extent of coronary artery disease (CAD) and in vitro cholesterol efflux capacity. Design - This study consisted of 46 type 2 diabetic, and 42 nondiabetic men undergoing coronary angiography. Quantitative coronary angiography was used to estimate the severity, extent, and overall "atheroma burden" of CAD. The capacity of patient plasma to induce cholesterol efflux from cultured Fu5AH rat hepatoma cells was measured in vitro. Results - In the combined study population (n = 88), there was a significant inverse correlation between efflux and global atheroma burden (r = -0.23, p < 0.05). In the diabetic group, the global atheroma burden index was independently associated both with cholesterol efflux and with LpA-I levels. However, in the nondiabetic CAD group this association was lost when efflux and LpA-I levels were included in the same model. Conclusion - The present study demonstrated that efflux capacity was inversely associated with the severity and extent of CAD. In the diabetic group this association was independent of LpA-I levels, suggesting impaired antiatherogenic potential of these particles in type 2 diabetic patients.     

Inverse Association Between Birth Weight,Birth Length and Serum Total Cholesterol in Adulthood

Objectives - To investigate whether impaired fetal growth, measured by low birth weight and short birth length, is linked with raised levels of serum lipids and increased risk and mortality of coronary heart disease. Design - The association between birth length, birth weight, Ponderal Index and total serum cholesterol was examined in 545 Danish men and women aged 31 to 51 years who participated in the Ebeltoft Health Promotion Project in Denmark. Results - No associations were found in women. For men, a negative association was found between birth weight and serum total cholesterol, with a fall in mean serum total cholesterol from 6.03 mmol/l at birth weight below 3300 g to 5.64 mmol/l at birth weight above 4000. A similar association was found between birth length and serum cholesterol, with a mean value of 6.23 mmol/l at birth length below 51 cm and a mean value of 5.56 mmol/l at birth length above 54 cm. No associations were found for Ponderal Index. Between 3% and 8% of the variance in serum total cholesterol could be explained by the statistical models used in this study. Conclusion - Our findings support the hypothesis of a negative association between birth weight, birth length and elevated serum cholesterol in adult life, but only in men.     

Effects of squalene on expression of LDLR in HepG2 cells and its mechanism北大核心CSCD

Aim To investigate the effect of squalene on LDLR expression in HepG2 cells and its mechanism of down-regulated cholesterol. Methods The proliferation of HepG2 cells exposed to squalene at different concentrations was measured by MTT assay. The effect of squalene on the expression of LDLR in HepG2 cells was measured by flow cytometry and fluorescence mi-croscopy. The effect of different concentrations of squalene on the interaction between SCAP and Insig2, two key protein molecules of SREBP pathway, was assayed by FRET technology. Results MTT results showed that squalene had inhibitory effect on the proliferation of HepG2 cells in a dose-dependent manner. Flow cytometry and fluorescence microscopy results showed that squalene enhanced LDLR expression in HepG2 cells compared with the control group. The results of FRET technology revealed that compared with model control group, the YFP fluorescence value in Squalene group dramatically declined, and the YFP fluorescence value of each drug group decreased with the range of 5-25 |xmol L1 squalene concentration. Conclusions Squalene may promote the expression of LDLR in HepG2 cells through inhibiting the interaction between SCAP and Insig2 proteins in SREBP pathway, which may confirm that squalene is a potential novel drug for the down-regulation of cholesterol level. © 2018 Publication Centre of Anhui Medical University. All rights reserved.     

The role of lipids in the pathogenesis of glomerulosclerosis in the rat following subtotal nephrectomy

Abstract. Similarities between atherosclerosis and glomerulosclerosis suggest that hyperlipidaemia may contribute to glomerular injury. Dietary supplementation with 4% cholesterol +1% cholic acid was administered to rats 4 weeks after 1 1/3 nephrectomy and continued for 7 weeks. There was a significant increase in serum cholesterol (peak= 11.52 ±1.09 mmol 1^-1 vs. 4.73 ± 0.31 on control diet, < 0.001) and triglyceride concentrations (peak = 2.31 ± 0.27 mmol 1^-1 vs. 1.41 ±0.29, <0.05) and a marked increase in βmigrating lipoproteins. The severity of hypercholester-olaemia was significantly correlated with proteinuria (control diet: r = 0.600, cholesterol diet: r = 0.672, < 0.0001) as was hypertriglyceridaemia (control diet: r = 0.544, cholesterol diet: r = 0.678, <0.0001). The percentage of glomeruli containing lipid deposits was increased from 21% to 60% (<0.05). The kidney total cholesterol content was increased from 29.2 ±0.8 to 47.7 ± 3.3 μmols g^-1 dry weight (<0.0001), with esterified cholesterol increasing from 7.5 ± 0.4% to 14.5 ± 2.1% of total (<0.01). Serum cholesterol concentration was significantly correlated with both glomerular lipid deposition ( r _s= 0.7195, <0.0001) and tissue total cholesterol content ( r _s= 0.6053, <0.001). Lipid vacuolation was prominent in the paramesangium and within mesangial cells. Despite these changes hypertension, uraemia, proteinuria and glomerulosclerosis were not significantly increased on the cholesterol diet. Cholesterol deposition in the glomeruli occurs secondary to hyperlipidaemia in rats following subtotal nephrectomy but over 7 weeks no exacerbation of glomerulosclerosis is detectable.