Hepatitis C virus relies on lipoproteins for its life cycle

Hepatitis C virus(HCV) infects over 150 million people worldwide. In most cases, HCV infection becomes chronic causing liver disease ranging from fibrosis to cirrhosis and hepatocellular carcinoma. Viral persistence and pathogenesis are due to the ability of HCV to deregulate specific host processes, mainly lipid metabolism and innate immunity. In particular, HCV exploits the lipoprotein machineries for almost all steps of its life cycle. The aim of this review is to summarize current knowledge concerning the interplay between HCV and lipoprotein metabolism. We discuss the role played by members of lipoproteins in HCV entry, replication and virion production.

新型均相酶法检测sd LDL—C试剂盒的性能评价

目的 评价小而密低密度脂蛋白胆固醇（sd LDL-C）均相酶法检测试剂盒的性能.方法参照CLSI EP文件及其它文献,评估新型sd LDL-C均相酶法液态双试剂检测试剂盒的灵敏度、精密度、线性范围、抗干扰能力和携带污染率,并以密度梯度超速离心法（DUGC）为参比方法,评价新型sd LDL-C均相酶法液态试剂盒的准确度.结果均相法各项精密度及特异度良好,灵敏度可达0.048 mmol/L,低值样本和高值样本的总精密度分别为8.69%和4.64%,测定结果与DUGC法相关性良好（Y=1.065 4X-1.8354）,线性范围上限可达2.634 mmol/L,可以抵抗临床中常见的干扰现象,符合试剂说明书的参数和临床应用的要求.结论新型sd LDL-C均相酶法检测试剂盒各项性能良好,是一种可用于临床常规的快速简便sd LDL-C检测方法.

维生素 C 对 LDL 受体活性的影响

研究了维生素Ｃ（ＶＣ）对培养的人皮肤成纤维细胞低密度脂蛋白（ＬＤＬ）受体活性的影响。从ＬＤＬ受体饱和分析和Ｓｃａｔｃｈａｒｄ作图以及单点分析表明，ＶＣ可增加细胞ＬＤＬ受体量，但不影响受体对ＬＤＬ的亲和力。提示ＶＣ通过增加ＬＤＬ受体活性而促进胆固醇代谢，具有一定的抗动脉粥样硬化作用。

益经汤对去势雌性大鼠体重和TC LDL HDL影响的研究

目的:探讨益经汤对去势雌性大鼠体重和血脂的影响。方法:大鼠分为模型组和假手术组,模型组大鼠结扎切除卵巢,假手术组大鼠手术暴露卵巢但不切除。造模成功后,随机分为假手术组、模型组、益经汤高剂量组(24 g/kg)、益经汤低剂量组(12 g/kg)、西药补佳乐组(0.09 mg/kg)。假手术组和模型组灌同等体积的生理盐水,每天1次,连续给药6周后,腹主动脉采血,分离血清测定总胆固醇(TC)、低密度脂蛋白(LDL)、高密度脂蛋白(HDL)水平。实验大鼠随机分组后,称初重,手术4周后称重,采集标本前称终重。结果:模型组动物体重明显增加,与假手术组、益经汤高剂量组比较,差异有显著性(P<0.01);益经汤高剂量组在降低TC、LDL方面,与模型组相比差异有显著性(P<0.01)。结论:益经汤高低剂量组和西药补佳乐组可明显延缓去势雌性大鼠体重增长,益经汤高剂量组能够纠正去势雌性大鼠的脂代谢紊乱状态。

High-density lipoproteins:an emerging target in the prevention of cardiovascular disease

High-density lipoproteins （HDLs） have been well established to protect against the development of atherosclerotic cardiovascular disease. It has become apparent that in addition to the promotion of reverse cholesterol transport, HDLs possess a number of additional functional properties that may contribute to their beneficial influence on the arterial wall. A number of exciting therapeutic strategies have been developed that target HDL and its ability to protect against the development of atherosclerotic plaque. This paper will review how the promotion of the functional properties of HDL inhibits the formation of atherosclerotic plaque and stabilises lesions in patients with established disease.

High density lipoproteins and type 2 diabetes:Emerging concepts in their relationship

Patients with type 2 diabetes mellitus(T2DM) frequently exhibit macrovascular complications of atherosclerotic cardiovascular(CV) disease. High density lipoproteins(HDL) are protective against atherosclerosis. Low levels of HDL cholesterol(HDL-C) independently contribute to CV risk. Patients with T2 DM not only exhibit low HDL-C, but also dysfunctional HDL. Furthermore, low concentration of HDL may increase the risk for the development of T2 DM through a decreased β cell survival and secretory function. In this paper, we discuss emerging concepts in the relationship of T2 DM with HDL.

Metabolism of high density lipoproteins in liver cancer

Liver plays a vital role in the production and catabolism of plasma lipoproteins. It depends on the integrity of cellular function of liver, which ensures homeostasis of lipid and lipoprotein metabolism. When liver cancer occurs these processes are impaired and high-density lipoproteins are changed.

Potential antioxidant and cytoprotective effects of essential oil extracted from Cymbopogon citratus on OxLDL and H_(2)O_(2) LDL induced Human Peripheral Blood Mononuclear Cells(PBMC)

Cymbopogon citratus(lemon grass)is commonly used in traditional folk medicine.The essential oil extracted from C.citratus has been reported as a potential anti-oxidant and anti-inflammatory agent.This study has been designed to explore the protective effect of C.citratus(lemon grass)against modified LDL(OxLDL and H2O2 LDL)induced cytotoxicity in Peripheral Blood Mononuclear Cells(PBMC).The essential oil extracted from C.citratus(EOC)was subjected to FT-IR spectroscopic analysis for the identification of functional groups.In vitro antioxidant assays were carried out to assess the electron donating capability of EOC as compared with a known standard L-ascorbic acid.The cytoprotective effects of EOC were determined in PBMC induced with modified LDL.Spectra obtained from FT-IR analysis showed the presence of functional groups in EOC such as H-bonded,O-H stretching,N-H stretching,aldehyde-C-H stretching,aldehyde/ketone-C=O stretching,-C=C-stretching,-CH_(3) bending,-C-H in plane bending.EOC has greater antioxidant property when compared with the standard L-ascorbic acid.EOC at all test concentrations demonstrated free radical scavenging activity and cytoprotective effect when challenged against modified LDL in PBMC.The above results show EOC as a promising antioxidant and cytoprotective agent.

血府逐瘀汤对气滞血瘀型CHD血浆HCY LDL-C水平的影响

目的:探讨血府逐瘀汤对气滞血瘀型冠心病(CHD)疗效及对血浆同型半胱氨酸(HCY)、低密度脂蛋白胆固醇(LDL-C)水平的影响。方法:将86例CHD患者据病情轻重程度随机分为中西药结合组和西药组,予以相同的西药基础治疗,中西药结合组加用血府逐瘀汤治疗,并对治疗前后血浆HCY、LDL-C水平进行统计学处理。结果(:1)中西药结合组和西药组血浆HCY、LDL-C水平治疗前均无显著性差异(P>0.05),治疗后均有显著性差异(P<0.05)。且HCY、LDL-C二者治疗前后均呈显著正相关(r=0.4011,r=0.4018,P<0.01);(2)中西药结合组与西药组有效率比较有显著性差异(P<0.05)。结论(:1)气滞血瘀型CHD患者血浆HCY、LDL-C水平治疗前后均呈显著正相关,提示二者存在着相关关系。(2)血府逐瘀汤有显著抗高HCY血症、高LDL-C血症的作用。

Selective Removal of Low-Density Lipoproteins from Blood by Induced Precipitation with AAS in Vitro(Ⅰ)

1 INTRODUCTION It’s evident that high level of cholesterol in blood is associated with the formation and devel-opment of familial hypercholestrolemia(FH)and atherosclerosis(AS).In general,choles-terol in blood is mainly combined with low-density lipoproteins(LDL),very low-densitylipoproteins(VLDL)and high density lipoproteins(HDL).About 60%-80% cholesterolexists in LDL and VLDL.LDL and VLDL have been recognized as the principal

氧化修饰 LDL 对体外培养的主动脉壁内皮细胞的影响

目的探讨氧化修饰低密度脂蛋白（ｏｘｉｄａｔｉｖｅｌｙｍｏｄｉｆｉｅｄｌｏｗｄｅｎｓｉｔｙｌｉｐｏｐｒｏｔｅｉｎ，ｏｘＬＤＬ）导致动脉粥样硬化形成的途径及可能机制。方法在体外培养的小牛主动脉内皮细胞（ｂｏｖｉｎｅａｏｒｔｉｃｅｎｄｏｔｈｅｌｉａｌｃｅｌ，ＢＡＥＣ）中加入ｏｘＬＤＬ，终浓度为０．１ｍｇＰｒ／ｍｌ，培养２４ｈ后，采用细胞毒试验、流式细胞仪、丙二醛（ＭＤＡ）测定及细胞计数等方法分别对其贴壁细胞及培养液进行了检测。结果加ｏｘＬＤＬ组与对照组（未加ｏｘＬＤＬ组）相比，发现：①在相差显微镜下，ｏｘＬＤＬ组细胞形态明显拉长，发生脱落，并存在大片脱失区；②细胞毒试验发现ｏｘＬＤＬ对ＢＡＥＣ的生长增殖有明显的抑制作用；③流式细胞仪检测发现ｏｘＬＤＬ抑制ＢＡＥＣ由Ｇ１期进入ＤＮＡ合成的Ｓ期，且ｏｘＬＤＬ可诱导ＢＡＥＣ凋亡的发生；④ＭＤＡ检测发现ｏｘＬＤＬ促进ＢＡＥＣ脂质过氧化物生成；⑤加ｏｘＬＤＬ组ＢＡＥＣ粘附的ＨＬ６０细胞数明显多于对照组。结论由ｏｘＬＤＬ作用引起的内皮细胞形态损伤、增殖抑制、脂质过氧化物生成增多及单核细胞粘附性增加等改变可能是动脉粥样硬化形成的机制之一。

糖尿病患者ox LDL、Lp(a)的检测意义

目的:了解糖尿病患者血浆axLDL和血清Lp(a)的变化。方法:用ELISA双抗体夹心法检测。结果:表明糖尿病患者axLDL和Lp(a)与健康对照组比较有极显著性差异(P<0.01),糖尿病Ⅰ型与Ⅱ型比较有显著差异(P<0.05)。意义:axLDL和Lp(a)升高与糖尿病有密切关系。

Effect of low-density lipoproteins, spermatozoa concentration and glycerol on functional and motility parameters of bull spermatozoa during storage at 4℃

An extender has been developed with low-density lipoproteins （LDLs） that eliminates the microbial risks associated with the use of whole egg yolk. The objective of this study was to assess the effects of substituting egg yolk with LDLs for use as an extender in sperm preservation at 4 ℃, as well as on spermatozoa motility, plasma membrane and acrosome integrity, at two different concentrations （80×10^6 and 240× 10^6 sperm per ml） for 8 days and to evaluate glycerol toxicity in both extenders. A total of 12 ejaculates were collected from three bulls. Spermatozoa motility was examined using computer-assisted semen analysis. Plasma membrane integrity was determined using the hypo-osmotic swelling test and acrosome integrity with the fluorescein isothiocyanate-Pisum sativum agglutinin test. The semen was subsequently divided into four aliquots and diluted with Tris-egg yolk-glycerol （TEG）, Tris-egg yolk without glycerol （TE）, LDL with glycerol （LDL＋） and LDL without glycerol （LDL-）, at 80×10^6 and 240 ×10^6sperm per ml. This study showed that the LDL＋ and LDL- extenders were more effective at preserving spermatozoa motility, plasma membrane integrity and acrosome integrity than TEG and TE （P〈0.05） during 8 days of incubation. After 3 days of incubation, a toxicity of glycerol was observed in TEG, whereas no significant difference was observed between LDL＋ and LDL-. We can therefore conclude that the LDL extender can be used to refrigerate semen at 4 ~C instead of TEG and TE at 80×10^6and 240×10^6 sperm per ml for elite bulls. This finding can be used to define a policy for the storage of high-quality bull semen.

ApoB-containing lipoproteins promote infectivity of chlamydial species in human hepatoma cell line

AIM:To evaluate the direct binding of two main chlamydial biovars(C.trachomatis and C.pneumoniae) to plasma lipoproteins and its effect on chlamydial infection rate in human hepatoma cell line(HepG2 cells). METHODS:Murine plasma lipoproteins were fractionated and isolated using fast-performance liquid chromatography(FPLC),spotted on nitrocellulose membrane and incubated with chlamydial suspensions. Direct binding of chlamydial particles to lipoprotein fractions has been studied using lipopolysaccharide-specific antibodies in immuno-dot blot binding assay and immunoprecipitation analysis.Immunostaining protocol as well as flow cytometry analysis have been employed to study the infectivity rate of chlamydial species in HepG2 cells. RESULTS:Elementary bodies of both C.trachomatis and C.pneumoniae bind ApoB-containing fractions of plasma lipoproteins.That binding becomes stronger when heat-denatured FPLC fractions are used, suggesting a primary role of apolipoproteins in interaction between chlamydial particle and lipoprotein. Both chlamydial biovars efficiently propagate in human hepatoma cell line-HepG2 cells even in serum free conditions forming late-stage inclusion bodies and releasing extracellular elementary bodies.Preincubation of C.trachomatis and C.pneumoniae with native ApoB-containing lipoproteins enhances the rate of chlamydial infection in HepG2 cells.CONCLUSION:A productive infection caused by C. trachomatis and C.pneumoniae may take place in human-derived hepatocytes revealing hepatic cells as possible target in chlamydial infection.Obtained results may suggest the participation of lipoprotein receptors in the mechanism of attachment and/or entry of chlamydial particles into target cells.

EFFECTS OF MODULATED LDLs ON THE RELEASE OF ENDOTHELIN-1 AND PROSTACYCLIN BY ENDOTHELIAL CELLS IN CULTURE

Objective To study the releases of endothelin-1 and prostacyclin by endothelial cells in culture and to elucidate how these releases were influenced by smoke-treated low density lipoprotein. Methods We exposed en- dothelial cell cultures to native or oxidized low density lipoproteins,low density lipoproteins treated by dimethylsul- foxide-soluble particles from cigarette smoke or dimethylsulfoxide alones. The release of endothelin-1 was assayed by bioassay and the release of prostacyclin was assayed by radioimmunoassay. Results Low density lipoproteins treated by smoke significantly increased the release or endothelin-1 (P<0.025) and decreased the release of prostacyclin (P< 0.02) by endothelial cells in culture, contrast to native or dimethylsulfoxide-treated lipoproteins. Conclusion The main part or vasoconstrictor activity in conditioned medium from bovine aortic EC is endothelin-1.

Changes Induced by Physical Activity, Weight Loss and Calorie Restriction in Body Composition, Lipoproteins and Functional Capacity in Obese Congolese Women

Background. The effects of physical exercises combined with a low-calorie diet on weight loss, body composition, lipoproteins profile, and physical fitness had been well described. However, Central Africa’s studies investigating these kinds of diets and exercise regimens are lacking. Objective. To investigate the effects of adding 14-weeks exercises to a hypocaloric diet on changes in body composition, lipoproteins concentrations, and physical capacities in obese Congolese women. Population and Methods. In total, 34 obese women aged 30 - 39 years (mean age: 33.7 ± 2.4 years) assigned to 14-weeks training program and low energy ketogenic diet. Body composition was assessed using classic methods and impedancemetry. Fasting plasma glucose (FPG) and fasting serum insulin were assessing using enzymatic colorimetric and radioim-munoradiometric methods. HOMA-IR and lipoproteins concentrations were assessed using standardized laboratory methods. VO2peak was measured on a treadmill during a progressive exercise test. Speed, cadence and stride length were measured along the 10-m level walkway. Muscular endurance was measured using the tests of sit-up and inflections-extensions of elbows. All the variables of the study were assessed at the beginning, in the 7-weeks, and in the 14-weeks of training methods. Results. Declines in body weight (16%), percent fat (12.1%), fat weight (26.4%), abdominal fat (34.2%), and waist circumference (10.4%) were found. A significant decrease in FPG (13%), fasting serum insulin (60.9%), HOMA-IR (64.7%), total cholesterol (12.2%), LDL-cholesterol (20.3%), triglycerides (92.8%), and VLDL-triglycerides (17.5%) was shown. In contrast, significant increase in HDL-cholesterol (27.13%) was found. The peak oxygen consumption VO2peak relative to body weight improved more in the 14-weeks training program (13.4%). Obese women exhibited higher values in the 14-weeks training program for speed gait (16.5%), cadence (9.1%), and stride length (15.7%) during normal walk and rapid walk. Weight loss combined with a low-calorie diet and 14-weeks training program improved significantly muscular endurance capacities. Conclusion. Exercise added to hypocaloric diet leads to decreases in body composition, to improve in insulin sensitivity, to enhancement of VO2peak and functional fitness. This may be helpful for the treatment of the metabolic complications of abdominal obesity.

Nanotechnologies meeting natural sources:Engineered lipoproteins for precise brain disease theranostics

Biological nanotechnologies have provided considerable opportunities in the management of malignancies with delicate design and negligible toxicity,from preventive and diagnostic to therapeutic fields.Lipoproteins,because of their inherent blood-brain barrier permeability and lesion-homing capability,have been identified as promising strategies for high-performance theranostics of brain diseases.However,the application of natural lipoproteins remains limited owing to insufficient accumulation and complex purification processes,which can be critical for individual therapeutics and clinical translation.To address these issues,lipoprotein-inspired nano drug-delivery systems(nano-DDSs),which have been learned from nature,have been fabricated to achieve synergistic drug delivery involving site-specific accumulation and tractable preparation with versatile physicochemical functions.In this review,the barriers in brain disease treatment,advantages of state-of-the-art lipoprotein-inspired nano-DDSs,and bio-interactions of such nano-DDSs are highlighted.Furthermore,the characteristics and advanced applications of natural lipoproteins and tailor-made lipoprotein-inspired nano-DDSs are summarized.Specifically,the key designs and current applications of lipoprotein-inspired nano-DDSs in the field of brain disease therapy are intensively discussed.Finally,the current challenges and future perspectives in the field of lipoprotein-inspired nano-DDSs combined with other vehicles,such as exosomes,cell membranes,and bacteria,are discussed.

Effect of swirling flow on LDL and ox-LDL uptake in rabbit thoracic aorta

Object To elucidate the physiological significance of the spiral flow in the arterial system from the viewpoint of atherogenic lipid transport,an ex vivo experimental comparative

Helicobacter Pylori Infection Is Associated with Dyslipidemia and Increased Levels of Oxidized LDL in Type-2 Diabetes Mellitus

Emerging data now indicate and address the strong relationship between H. pylori infection and the incidence of Type 2 DM, a growing body of evidence suggests that the infection with H. pylori may be associated with insulin resistance, chronic inflammation, long-term diabetes complications, and cardiovascular risk factors. The present study was conducted to evaluate the relationship between the infection with Helicobacter pylori and disturbance in Lipid profile in Type 2 Diabetic patients. One hundred and five participants were enrolled, categorized into two groups of H. pylori positive cases and negative controls according to their results of H. pylori IgG antibodies. Subjects in both groups fill the structured questionnaire. Blood samples were drawn for measuring the FBS, 2hr-PP blood sugar, HbA1c, Lipid profile and oxidized LDL. The obtained results were statistically analyzed. The study methodology was approved by the Biomedical Ethics Committee in the Faculty of Medicine, Umm Al-Qura University, Makkah, KSA. 48 cases (45.7%) were diagnosed as H. pylori seropositive and 57 (54.3%) were negative. There is no significant difference in the mean age or mean BMI between the H. pylori negative and positive cases. Glycemic control was similar in the two groups. Total Cholesterol was higher in cases of positive H. pylori compared to negative controls (P < 0.001) and Triglycerides was significantly elevated too (P < 0.005). No significant difference in the levels of HDL-Cholesterol between the two groups, while the mean LDL-Cholesterol was found to be significantly increased in cases of H. pylori positive compared to negative controls (P < 0.001). Oxidized LDL levels in the positive cases was found to be increased significantly (P = 0.001) compared to negative controls. Infection with H. pylori is associated with increased levels of Total Cholesterol, Triglycerides, LDL-C and oxidized LDL in Type 2 Diabetic patients.

急性冠状动脉综合征患者血浆CXC趋化因子配体16 TC TG HDL-C LDL-C检测及相关性研究

目的:通过检测血浆中CXC趋化因子配体16 TC TG HDL-C LDL-C的含量,探讨与ACS的关系。方法:采用ELISA法定量检测血浆CXCL16含量,同时用全自动生化分析仪检测TC TG HDL-C LDL-C在血浆中的含量。结果:血清水平LDL-C在冠心病各组及胸痛对照组中差异有统计学意义,各组血浆CXC16水平差异有统计学意义。结论:我国随着生活水平的提高,在中等以上城市高脂血症和动脉粥样硬化病的发生越来越多,ACS包括不稳定性心绞痛(UAP),非ST段抬高性急性心肌梗死(NSTEMI)和ST段抬高性心肌梗死(STEMI)稳定性心绞痛(SAP),是严重威胁人类生命的重大疾病之一。高脂血症特别是高TC高LDL-C在动脉粥样硬形成中起重要作用。人CXC趋化因子配体16是属于CXC趋化因子亚家族的重要成员,它以可化溶性或跨膜表达2种形式存在,具有趋化因子、清道夫受体及黏附分子等3种分子的功能,在动脉粥样硬化的发生发展中起重要作用,因此对它们的研究及探讨对急性冠状动脉综合征的影响越来越受到人们的重视。