Function and Significance of Very Low Density Lipoprotein Receptor Subtype Ⅱ

To explore the functions of very low density lipoprotein receptor (VLDL-R) subtype II in lipoprotein metabolism and foam cells formation, the recombinant plasmid with the two subtypes cDNA was constructed respectively, the ldl-A7 cell lines were transfected and two cell lines expressing VLDL-R were obtained: one stably expressing the VLDLR with the O-linked sugar region (type I VLDLR) and the other without the O-linked sugar region (type II VLDLR). In the study on binding of VLDLR to their nuclein labeled natural ligands (VLDL and β-VLDL), it was found that surface binding of 125I-VLDL or 125I-β-VLDL of ldl-A7 cells transfected with type I VLDLR recombinant (ldl-A7-VRI) was more higher than that of ldl-A7 cells transfected with type II VLDLR recombinant (ldl-A7-VRII). After being incubated with VLDL for different time, the contents of triglyceride and total cholesterol in cells were mensurated, and the formation of foam cells and accumulation of lipid in cells was observed by oil-red O staining. The results showed that the contents of triglyceride and total cholesterol in ldl-A7-VR I were much higher than those in ldl-A7-VR II, and ldl-A7-VR I could transform into foam cells notably. It was suggested that type I VLDLR binds with relative higher affinity to VLDL and β-VLDL, and internalizes much more lipoprotein into cells. As a result, we can conclude that type I VLDLR plays a more important role in lipoprotein metabolism and foam cells formation than type II VLDLR.

Hypercholesterolemia,low density lipoprotein receptor and proprotein convertase subtilisin/kexin-type 9

Atherosclerotic cardiovascular disease is the main cause of mortality and morbidity in the world. Plasma levels of low density lipoprotein cholesterol （LDL-C） are positively correlated with the risk of atherosclerosis. High plasma LDL concentrations in patients with hypercholesterolemia lead to build-up of LDL in the inner walls of the arteries, which becomes oxidized and promotes the formation of foam cells, consequently initiating atherosclerosis. Plasma LDL is mainly cleared through the LDL receptor （LDLR） pathway. Mutations in the LDLR cause familiar hyperch- olesterolemia and increase the risk of premature coronary heart disease. The expression of LDLR is regulated at the transcriptional level via the sterol regulatory element binding protein 2 （SREBP-2） and at the posttranslational levels mainly through proprotein convertase subtilisin/kexin-type 9 （PCSK9） and inducible degrader of the LDLR （IDOL）. In this review, we summarize the latest advances in the studies of PCSK9.

Effect of Curcumin on the Gene Expression of Low Density Lipoprotein Receptors

Objective： To investigate the molecular mechanisms and effective target ponits of lipid-lowering drug, Rhizoma Curcumae Longae, and study the effect of curcumin on the expression of low density lipoprotein （LDL） receptors in macrophages in mice. Methods. Macrophages in mice were treated with curcumin, which was purified from the ethanolly extraction of Rhizoma Curcumae Longae for 24 h. The LDL receptors expressed in the macrophages were determined by enzyme-linked immunosorbent assay （ELISA） and assay of Dil labeled LDL uptake by flow cytometer. Results： It was found for the first time that 10 μmol/L-50 μmol/L curcumin could obviously up-regulate the expression of LDL receptor in macrophages in mice, and a dose-effect relationship was demonstrated. Conclusion： One of the lipid-lowering mechanisms of traditional Chinese medicine, Rhizoma Curcumae Longae, was completed by the effect of curcumin through the up-regulation of the expression of LDL receptor.

ASSOCIATION BETWEEN LOW- DENSITY LIPOPROTEIN RECEPTOR- RELATED PROTEIN GENE, BUTYRYLCHOLINESTERASE GENE AND ALZHEIMER'S DISEASE IN CHINESE

Objective. To research the relations between low- density lipoprotein receptor- related protein gene (LRP) polymorphism, butyrylcholinesterase gene (BchE) polymorphism and Alzheimer’s disease (AD) in Chinese. Methods. The gene polymorphisms of LRP and BchE were genotyped in 38 AD cases and 40 controls with polymerase chain reaction- restriction fragment length polymorphism (PCR- RFLP) methods. AD groups were classified according to the LRP C/C genotype and compared with matched controls. Results. AD group had higher frequencies of C/C homozygote (81.6％ vs 60.0％ , P< 0.05) and of C allele (89.5％ vs 76.3％ , P< 0.05),with no significant difference between any of these LRP genotypes classified AD groups and their respective control groups. Conclusions. A positive correlation was found between LRP gene polymorphism and AD, but not between BchE gene polymorphism and AD in Chinese AD cases.

Roles of low?density lipoproteinreceptor?related protein 1 in tumors

Low-density lipoprotein receptor-related protein 1(LRP1,also known as CD91),a multifunctional endocytic and cell signaling receptor,is widely expressed on the surface of multiple cell types such as hepatocytes,fibroblasts,neurons,astrocytes,macrophages,smooth muscle cells,and malignant cells.Emerging in vitro and in vivo evidence demonstrates that LRP1 is critically involved in many processes that drive tumorigenesis and tumor progression.For example,LRP1 not only promotes tumor cell migration and invasion by regulating matrix metalloproteinase(MMP)-2and MMP-9 expression and functions but also inhibits cell apoptosis by regulating the insulin receptor,the serine/threonine protein kinase signaling pathway,and the expression of Caspase-3.LRPI-mediated phosphorylation of the extracellular signal-regulated kinase pathway and c-jun N-terminal kinase are also involved in tumor cell proliferation and invasion.In addition,LRP1 has been shown to be down-regulated by microRNA-205 and methylation of LRP1CpG islands.Furthermore,a novel fusion gene,LRP1-SNRNP25,promotes osteosarcoma cell invasion and migration.Only by understanding the mechanisms of these effects can we develop novel diagnostic and therapeutic strategies for cancers mediated by LRP1.

Association between Low-density Lipoprotein Receptor-related Protein 5 Polymorphisms and Type 2 Diabetes Mellitus in Han Chinese:a Case-control Study

Objective To investigate the association between low-density lipoprotein receptor-related protein 5 （LRPS） variants （rs12363572 and rs4930588） and type 2 diabetes mellitus （T2DM） in Han Chinese. Methods A total of 1842 T2DM cases （507 newly diagnosed cases and 1335 previously diagnosed cases） and 7777 controls were included in this case-control study. PCR-RFLP was conducted to detect the genotype of the two single nucleotide polymorphisms （SNPs）. Odds ratios （ORs） and 95% confidence intervals （95% CIs） were calculated to describe the strength of the association by logistic regression. Results In the study subjects, neither rs12363572 nor rs4930588 was significantly associated with T2DM, even after adjusting for relevant covariates. When stratified by body mass index （BMI）, the two SNPs were also not associated with T2DM. Among the 3 common haplotypes, only haplotype ~ was associated with reduced risk of T2DM （OR 0.820, 95% CI 0.732-0.919）. In addition, rs12363572 was associated with BMI （P〈0.001） and rs4930588 was associated with triglyceride levels （P=0.043） in 507 newly diagnosed T2DM cases but not in healthy controls. Conclusion No LRP5 variant was found to be associated with T2DM in Han Chinese, but haplotype TT was found to be associated with T2DM.

Investigation of the Distribution and Changes of VLDLR Subtype in Fibrotic Cardiac Muscles

Very low-density lipoprotein receptor (VLDLR) is the major receptor with which cells can uptake the triacylglycerol from blood. It is divided into two subtypes according to presence of O- linked sugar domain located in the VLDLR receptor immediately outside of the membrane. Type Ⅰ VLDLR contains the O-link domain, while type Ⅱhas no such domain. The type ⅠVLDLR are mainly found on the surface of human myocardial cells. The result of our quantitative polymerase chain reaction on the normal and fibrotic cardiac muscles showed that both subtypes and expression level of VLDLR on the myocardial cell surface did not vary significantly between the normal and the fibrotic cardiac muscles despite the presence of malfunction due to fibrosis. This finding suggests that fibrosis doesn't exert significant influence on the subtype and the expression of VLDLR on the sur- face of myocardial cells. Such inconsistence with the changes found in other fibrotic tissues is awaiting further studies.

Relationship between the low density lipoprotein receptor gene polymorphism and serum lipid levels in the Guangxi Bai Ku Yao population

Objectives Bai Ku Yao(White-trousers Yaos)is a special branch of Yao minority in China.They are now living in both Lihu and Baxu villages,Nandan County, Guangxi,China.The population size is about 30,000.The special customs and culture of Bai Ku Yao,including their special clothing,intra-ethnic marriages and alcohol intake are still completely conserved to the present day.In previous epidemiologic studies,we found that the serum lipid levels and the prevalence of hyperlipidaemia were lower in Bai Ku Yao than in Han Chinese from the same region.This ethnic difference in serum lipid profiles is still not well known.We hypothesized that there may be significant differences in some genetic polymorphismsssociation of low density lipoprotein receptor (LDL-R) genepolymorphism and several environmental factors with serum lipid levels in the Guangxi Bai Ku Yao and Han populations.Methods A total of 1024 subjects of Bai Ku Yao and 792 participants of Han Chinese were stud- ied by a stratified randomized cluster sampling.Epidemiological survey was carried out using internationally standardized methods.Information on demographics,socioeconomic status, and lifestyle factors was collected with standardized questionnaires. The height,weight,waist circumference,blood pressure, and serum total cholesterol(TC),triglyceride(TG), high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol(LDL-C),apolipoprotein(Apo) A1, and ApoB were measured.Body massindex(BMI,kg/m2) was calculated.Genotyping of the LDL-RAvaⅡwas performed by polymerse chain reaction and restriction fragment length polymorphism combined with gel electrophoresis,and then confirmed by direct sequencing.Results(l)The height,weight,serum TC,HDL-C,LDL-C,ApoAl levels and the ratio of ApoAl to ApoB were lower in Bai Ku Yao than in Han Chinese(P【0.01 for all),whereas the percentage of subjects who consumed alcohol or smoked cigarettes was higher in Bai Ku Yao than in Han Chinese(P【0.01 for each).(2) The frequency of A+ allele in Bai Ku Yao was 34.5%,and the frequencies of A-A-,A-A+ and A+A + genotypes were 42.6%,45.9%and 11.5%;respectively. The frequency of A+ allele in Han Chinese was 19.3%(P【0.001),and the frequencies of A-A-,A-A + and A+A+ genotypes were 64.9%,31.6%and 3.5%(P【0.001);respectively. The frequencies of A-A-,A-A+ and A+A+ genotypes in Bai Ku Yao were significant difference between males and females,between normal TC and high TC subgroup, and between normal LDL-C and high LDL-C subgroup (P【0.05 for all),whereas the frequencies of A- and A+ ? alleles in Han Chinese were significant difference between males and females(P【0.05).(3) Serum LDL-C levels in Bai Ku Yao were significant difference among the A-A-, A-A+ and A+A+ genotypes(P【0.05),the A+ carriers had higher serum LDL-C levels.Serum HDL-C levels in Han Chiese were significant difference among the A-A-,A-A + and A+A+ genotypes(P【0.01),the A+ carriers had higher serum HDL-C levels.(4) After adjusting other factors,the prevalence of LDL-C abnormality was still higher in Han Chiese than in Bai Ku Yao.The prevalence of TC abnormality in Han Chinese was almost twice high as in Bai Ku Yao. The age and diet were common risk factor for TC abnormality. No effect of AvaⅡgenotype or alcohol consumption on the TC abnormality was found,but the combination of geno-type and alcohol consumption can increase the prevalence of TC abnormality[Exp(B) =(1.154)].Age was negatively cor- related with TG level.Conclusions Serum TC and LDL-C levels were lower in Bai Ku Yao than in Han Chinese.There were significant differences in the AvaⅡallele and genotype frequencies between the he A+ carriers in Bai Ku Yao had higher serum LDL-C levels,whereas the A+ carriers in Han had higher serum HDL-C levels.Interactions between alcohol consumption or cigarette smoking and the LDL-R AvaⅡgenotype were also observed.The differences in the serum lipid profiles between the two ethnic groups might partly result from different genotypic frequency of LDL-R AvaⅡpolymorphism or differentgene-enviromental interactions.Bai Ku Yao and Han population,the frequency of A + allele was higher in Bai Ku Yao than in Han.T between the two ethnic groups.Therefore,the aim of the present study was to detect the

Antitumoral activity of low density lipoprotein-aclacinomycin complex in mice bearing H_(22) tumor

INTRODUCTIONCancer cells,which proliferate rapidly need largeamounts of cholesterol for new membrane synthesis,and high LDL receptor (LDLR) activity.LDL hasbeen proposed as a useful discriminatory vehicle forthe delivery of cytotoxic drugs to tumor cells.LDL presents many advantages as drug

基于ox-LDL/LOX-1信号通路探讨脂质代谢紊乱促进肺癌进展中的机制

目的基于氧化低密度脂蛋白(ox-LDL)/人凝集素样氧化低密度脂蛋白受体1(LOX-1)信号通路探讨脂质代谢紊乱促进肺癌进展的机制。方法收集81个已鉴定的具有成对相邻非癌组织(离肿瘤至少5 cm)的肺腺癌组织,使用免疫组织化学检测LOX-1表达。肺腺癌细胞系(A549、H1299细胞)中过表达LOX-1。用Transwell测定细胞侵袭能力。用不同浓度oxLDL处理细胞,并检测细胞中LOX-1表达情况。结果在包含原发性人肺癌和匹配的邻近非癌组织中,肿瘤中LOX-1染色比非癌组织样品明显增强(中值H分数99.4 vs.16.2,P<0.001)。高LOX-1表达与低生存显著相关(P<0.001)。与无淋巴结转移的患者相比,发生淋巴结转移患者的癌组织具有更高的LOX-1水平(中值H分数83.2 vs.121.1,P<0.01)。LOX-1过表达显著促进肺癌细胞的侵袭转移细胞数(P<0.01)。此外,LOX-1是ox-LDL诱导的肺癌细胞转移所必需的功能靶点。伊他替尼抑制LOX-1过表达的A549在体外的转移能力。结论LOX-1的表达随着oxLDL水平的升高而增加,并且LOX-1的表达上调促进了肺癌细胞的转移,其作用机制可能与激活Janus激酶/转录因子激活子(JAK1/STAT6)信号通路有关。

利伐沙班对氧化型低密度脂蛋白诱导的人脐静脉内皮细胞功能的影响

目的探讨利伐沙班(RIV)对氧化型低密度脂蛋白(Ox-LDL)诱导的人脐静脉内皮细胞(HUVEC)功能损伤的影响。方法根据干预措施,将实验分为空白对照组(A组,常规培养液),Ox-LDL组(B组,100μg/mL Ox-LDL的培养液),Ox-LDL+RIV125组(C1组,100μg/mL Ox-LDL和125 ng/mL RIV的培养液),Ox-LDL+RIV250组(C2组,100μg/mL Ox-LDL和250 ng/mL RIV的培养液)和Ox-LDL+RIV500组(C3组,100μg/mL Ox-LDL和500 ng/mLRIV的培养液),各组细胞均处理48 h。采用CCK-8法检测各组细胞存活率的变化,采用流式细胞术检测细胞凋亡情况,采用酶联免疫吸附试验(ELISA)检测白细胞介素1β(IL-1β)、白细胞介素6(IL-6)、肿瘤坏死因子-α(TNF-α)水平,采用免疫印迹(Western blot)法检测细胞核因子-κB(NF-κB)和尿激酶型纤溶酶原激活因子受体(uPAR)蛋白表达水平。结果与B组比较,C1组、C2组、C3组细胞存活率显著升高(P<0.05),细胞凋亡率和uPAR表达水平均显著降低(P<0.05);C3组IL-1β,TNF-α,IL-6水平和p-NF-κB p65表达水平显著降低(P<0.05)。结论RIV能显著恢复细胞活力、减少细胞凋亡和由Ox-LDL引起的炎性反应,可能通过NF-κB和uPAR的调节而发挥作用。

血清S-100B蛋白、可溶性凝集素样氧化低密度脂蛋白受体-1、胶质纤维酸性蛋白检测在新生儿缺血缺氧性脑病病情严重程度中的诊断价值

目的:探讨血清S-100B蛋白、可溶性凝集素样氧化低密度脂蛋白受体-1(sLOX-1)、胶质纤维酸性蛋白(GFAP)与新生儿缺血缺氧性脑病(HIE)病情严重程度的关系。方法:选择80例HIE患儿作为观察组,另选择90例健康新生儿作为对照组,收集所有患儿一般资料,并检测两组患儿血清S-100B蛋白、sLOX-1、GFAP水平,分析HIE患儿血清S-100B蛋白、sLOX-1、GFAP与病情严重程度的相关性及预后不良的影响因素。结果:对照组血清S-100B蛋白、sLOX-1、GFAP水平低于观察组(均P<0.05)。重度组血清S-100B蛋白、sLOX-1、GFAP水平高于中度组、轻度组和对照组(均P<0.05)。Pearson相关分析显示,疾病严重程度与HIE患儿血清S-100B蛋白、sLOX-1、GFAP水平呈正相关(均P<0.001)。随访预后良好患儿59例,预后不良21例,经多因素Logistic回归分析显示,产程异常、病情重度、S-100B蛋白、sLOX-1、GFAP为影响HIE患儿预后的危险因素(均P<0.05)。结论:HIE患儿病情严重程度和预后与血清S-100B蛋白、sLOX-1、GFAP水平有关,监测其水平变化有利于临床早期完善干预方案改善预后。

LRP5基因突变导致骨质疏松症-假性胶质瘤综合征一例报告

报告一例常染色体隐性遗传发病的骨质疏松症-假性胶质瘤综合征。先证者女性,23岁,父母非近亲结婚,出生后发现双目失明,婴儿期因发现右眼视网膜母细胞瘤行右眼球摘除术,9岁开始反复发生轻微外力骨折,诊断为成骨不全。查体发现脊柱侧凸畸形、胸廓畸形、双上肢肘外翻、四肢关节韧带松弛。双能X线吸收检测仪(dual energy X-ray absorptiometry,DXA)骨密度明显低于同龄人,腰椎1-4骨密度Z值-5,左髋骨密度Z值-1.8。X线摄片示全身骨小梁稀疏。Sanger测序显示低密度脂蛋白受体相关蛋白-5(lowdensity lipoprotein receptor-related protein 5,LRP5)基因的6号外显子和23号外显子发生复合杂合突变,导致p.Pro382Leu+p.Cys1611LeufsX33。本文通过文献复习对该病的临床表现和诊疗特点进行讨论及总结,以期帮助临床医生提高对这一疾病的认识。

血清KLK6、CCR2、ox-LDL水平与帕金森病的相关性研究

目的分析血清激肽释放酶6(KLK6)、CC趋化因子受体2(CCR2)、氧化修饰低密度脂蛋白(ox-LDL)与帕金森病的相关性。方法将2020年7月至2022年12月于该院诊治的帕金森病患者150例纳入研究作为患者组,按照Hoehn-Yahr(H-Y)分期进一步分为Ⅰ期27例、Ⅱ期42例、Ⅲ期47例、Ⅳ期34例。另外,选取同期健康体检者150例作为对照组。采用简易精神状态检查(MMSE)量表评估患者精神障碍情况。比较患者组与对照组及不同H-Y分期帕金森病患者血清KLK6、CCR2、ox-LDL水平。分析血清KLK6、CCR2、ox-LDL对帕金森病的诊断价值。分析血清KLK6、CCR2、ox-LDL与H-Y分期、MMSE评分的相关性。结果患者组血清KLK6、CCR2、ox-LDL水平高于对照组(P<0.05)。受试者工作特征(ROC)曲线分析显示,KLK6、CCR2、ox-LDL诊断帕金森病的曲线下面积(AUC)分别为0.813、0.847、0.826,最佳临界值对应的灵敏度、特异度:KLK6为66.7%、90.0%,CCR2为68.0、91.3%,ox-LDL为59.3%、100.0%。不同H-Y分期患者血清KLK6、CCR2、ox-LDL比较:Ⅰ期<Ⅱ期<Ⅲ期<Ⅳ期;MMSE评分比较:Ⅰ期>Ⅱ期>Ⅲ期>Ⅳ期;两两比较差异均有统计学意义(P<0.05)。血清KLK6、CCR2、ox-LDL水平与H-Y分期均呈正相关(r=0.559、0.716、0.722,P<0.05);血清KLK6、CCR2、ox-LDL水平与MMSE评分均呈负相关(r=-0.276、-0.448、-0.457,P<0.05)。结论血清KLK6、CCR2、ox-LDL对帕金森病患者具有一定的诊断价值,并且与帕金森病患者的病情严重程度和认知功能有关。

PCSK9转录后表达调控抑制剂的发现及活性研究

目的建立PCSK9转录后表达调控抑制剂高通量筛选模型筛选获得靶向PCSK9转录后水平的小分子抑制剂,通过其活性研究发现具有潜在降脂活性的PCSK9抑制剂。方法将PCSK9 mRNA的3'UTR区连接至荧光素酶报告基因下游以构建PCSK9转录后调控抑制剂高通量筛选模型,并对其进行优化与评价。应用该模型进行大规模筛选,进而利用荧光定量PCR、Western blot、流式细胞检测等方法对活性化合物调控PCSK9的表达及其介导的低密度脂蛋白受体(LDLR)的表达水平和低密度脂蛋白胆固醇(LDL-C)摄取作用的变化进行检测。结果利用上述模型筛选获得6个活性化合物,并对其量效关系进行分析,结果显示这些化合物均可呈剂量依赖性下调筛选模型荧光素酶活性;利用HepG2细胞对其调控PCSK9的表达水平进行检测,结果显示化合物IMB-57可显著抑制PCSK9基因mRNA水平和蛋白水平;进而对LDLR表达水平及摄取功能进行检测,结果显示IMB-57可显著增加细胞LDLR蛋白水平及其介导的细胞对LDL-C的摄取作用;初步分子机制分析结果证实IMB-57通过影响PCSK9基因mRNA的稳定性从而抑制其表达。结论活性化合物IMB-57具有显著的PCSK9抑制活性且可显著增加肝细胞LDL-C的摄取,有望发展为潜在的具有降脂活性的PCSK9小分子抑制剂,同时也证实本工作构建模型的可靠性,可用于具有全新机制的PCSK9抑制剂的发现。

绝经后2型糖尿病LRP5基因多态性与骨量异常的研究

目的分析低密度脂蛋白受体相关蛋白5(low density lipoprotein receptor related protein 5,LRP5)rs556442、rs312778位点基因多态性及突变在绝经后女性2型糖尿病(type 2 diabetes mellitus,T2DM)患者中骨量异常的意义。方法收集2021年5月至2023年5月新疆石河子地区的142例绝经后女性资料进行回顾性分析,分为正常对照组(A组,n=29)、T2DM组(B组,n=30)、骨量降低组(C组,n=28)、骨量降低+T2DM组(D组,n=55)。收集记录相关基线资料,运用全自动生化测定仪测定受试者血糖、血脂及骨代谢指标。通过双能X线骨密度仪测定骨密度(bone mineral density BMD),LRP5基因位点多态性采用飞行时间质谱法(MALDI-TOF-MS)测定,采用SNPscan技术对上述SNP位点进行基因分型。结果①四组基线资料比较,绝经年限、年龄及腰臀比(waist hip ratio,WHR)比较差异具有统计学意义(P<0.05);②与A组相比,B组的空腹血糖(FPG)、糖化血红蛋白(HbA1c)升高(P<0.05);D组的FPG、HbA1c的血清学水平升高,甘油三酯(TG)血清学水平降低(P<0.05);③rs556442位点:与A组相比,D组基因型分布(AA/AG/GG基因型)有统计学意义(P<0.05);rs312778位点组间基因型(CC/CT/TT基因型)及等位基因分布频率均无统计学意义(P>0.05);④rs556442位点:与AA基因型相比,B、C组AG/GG基因型的股骨颈BMD水平降低;D组AG/GG型的HDL血清学水平降低(P<0.05)。rs312778位点:与CC基因型相比,A组HbA1C、FPG血清学水平较CT/TT基因型低(P<0.05);D组CT/TT基因型的低密度脂蛋白(LDL)血清学水平升高(P<0.05);⑤多元线性回归分析:rs556442位点,TG增加是腰L_(1~4)BMD降低的危险因素(P<0.05);rs312778位点,体质量指数(body mass index,BMI)降低是腰L_(1~4)及股骨颈BMD降低的危险因素,TG增加是腰L_(1~4)BMD降低的危险因素(P<0.05);⑥在rs556442、rs312778位点骨量异常与基因型分布均无统计学意义(P>0.05)。结论新疆石河子地区绝经后T2DM女性患者LRP5基因rs556442、rs312778基因位点的突变可能与骨量降低有关。

Role of VLDL Receptor in the Process of Foam Cell Formation

The role of very low density lipoprotein receptor (LVLDR) in the process of foam cell formation was investigated. After the primary cultured mouse peritoneal macrophages were incubated with VLDL, β VLDL or low density lipoprotein (LDL), respectively for 24 h and 48 h, foam cells formation was identified by oil red O staining and cellular contents of triglyceride (TG) and total cholesterol (TC) were determined. The mRNA levels of LDLR, LDLR related protein (LRP) and VLDLR were detected by semi quantitative RT PCR. The results demonstrated that VLDL, β VLDL and LDL could increase the contents of TG and TC in macrophages. Cells treated with VLDL or β VLDL showed markedly increased expression of VLDLR and decreased expression of LDLR, whereas LRP was up regulated slightly. For identifying the effect of VLDL receptor on cellular lipid accumulation, ldl A7 VR cells, which expresses VLDLR and trace amount of LRP without functional LDLR, was used to incubate with lipoproteins for further examination. The results elucidated that the uptake of triglyceride rich lipoprotein mediated by VLDLR plays an important role in accumulation of lipid and the formation of foam cells.

miR-370-3p和LRP6对胎儿生长受限孕妇的临床诊断价值

目的探讨微小RNA-370-3p(miR-370-3p)和低密度脂蛋白受体相关蛋白6(LRP6)对胎儿生长受限(FGR)孕妇的临床诊断价值。方法选取2020年6月—2022年6月期间产检并确诊为FGR的孕妇96例为观察组,另选取同期产检的健康孕妇96例作为对照组,记录两组分娩孕周、1 min Apgar评分、5 min Apgar评分、新生儿体重、胎盘质量,依据美国妇产科学院(ACOG)标准将观察组划分为FGR组、严重FGR组。qRT-PCR法检测血清miR-370-3p和LRP6 mRNA表达水平;血清miR-370-3p和LRP6 mRNA水平与分娩孕周、1 min Apgar评分、5 min Apgar评分、新生儿体重、胎盘质量的相关性采用Pearson法分析;miR-370-3p和LRP6 mRNA对FGR的诊断价值采用ROC曲线评估。结果两组孕妇年龄、分娩孕周、是否初产的比例差异有统计学意义(P<0.05);观察组miR-370-3p显著高于对照组,LRP6显著低于对照组(P<0.05);严重FGR组miR-370-3p显著高于FGR组,LRP6显著低于FGR组(P<0.05);对照组与观察组新生儿体重、1 min Apgar评分、5 min Apgar评分及胎盘质量之间差异有统计学意义(P<0.05);miR-370-3p与LRP6之间呈负相关(r=-0.692,P<0.05),miR-370-3p与分娩孕周、新生儿体重、1 min Apgar评分、5 min Apgar评分、胎盘质量均呈负相关(r=-0.401、-0.382、-0.425、-0.484、-0.504,均P<0.05),LRP6与分娩孕周、新生儿体重、1 min Apgar评分、5 min Apgar评分、胎盘质量均呈正相关(r=0.306、0.412、0.512、0.612、0.419,均P<0.05);ROC曲线显示,miR-370-3p对FGR诊断的AUC为0.877(95%CI:0.821~0.919),截断值为1.40,其敏感度、特异性分别为67.71%、93.75%;LRP6对FGR诊断的AUC为0.838(95%CI:0.778~0.887),截断值为0.83,其敏感度、特异性分别为84.37%、71.87%;二者联合对FGR诊断的AUC为0.923(95%CI:0.875~0.956),明显高于二者单独诊断(Z联合vs miR-370-3P=2.811、P=0.005;Z联合vs LRP6=3.372、P=0.001),其敏感度、特异性分别为85.42%、87.50%。结论FGR患者血清miR-370-3p高表达、LRP6低表达,二者联合对FGR具有一定诊断价值。

Effect of Insulin on the Differential Expression of VLDL Receptor Isoforms of SGC7901 Cell and Its Biological Implication

This study examined the effect of insulin on the expression of very low density lipoprotein receptor (VLDLR) subtypes of SGC7901 cells and discussed its biological implication.In vitro, moderately or poorly-differentiated human gastric adenocarcinoma cell line SGC7901 was incubated with insulin for different lengths of time, and then the expression of protein and RNA level in VLDLR subtypes were detected by Western blotting and real-time PCR, respectively.The results showed that, at certain time interval, insulin could down-regulate expression of type Ⅰ VLDLR and up-regulate the expression of type Ⅱ VLDLR in SGC7901 cells, at both protein and RNA level.We are led to conclude that insulin serves as a regulator in maintaining the balance between glucose and lipid metabolism in vivo, possibly through its effect on the differential expression of VLDLR subtypes.