👤 Mingyue Yin

To clarify the differential expression of the genes related to the lipid metabolism in the early stage of atherosclerosis in the young LDLR-/- mice of different ages. A RT-PCR assay was used to analyse the gene expression patterns in the livers of LDLR-/- mice and wild type (WT) mice from 14 to 90 days. The characteristics of early lipid deposition in intima were evaluated using biochemical and pathological techniques. In LDLR-/- mice, when compared to WT mice, the mRNA level of the apolipoprotein A IV (apoA IV), fatty acid translocase (Fat/CD36) and carnitine palmitoyl transferase I (CPT I) changed prominently at the age of 14-days (P < 0.05). At 30 days, the mRNA level of apolipoprotein A I (apoA I) was up regulated, but apolipoprotein F (apoF), CD36 and CPT I were down regulated (P < 0.05). At 60 days, the mRNA levels of apoA I, CPT I and liver X receptor alpha (LXRalpha) were up regulated, but apoA IV was down regulated (P < 0.05). At 90 days, the level of the apoA I was higher, but the expression of the apoA IV, apoF and acyl-coenzymeA oxidase 1 (ACOX1) were down regulated (P < 0.05), whereas the expression of apolipoprotein A V (apoA V), apolipoprotein E (apoE), peroxidase proliferator-activated receptor alpha (PPARalpha) and angiopoietin-like protein 3 (angptl 3) had no significant changes (P > 0.05). The serum levels of TC (P < 0.05), TG (P < 0.05) and LDLC (P < 0.05) in LDLR-/- mice were significantly higher than those in wild type mice with the same age. The mRNA levels of the apoA I, apoA IV, apoF, FAT/CD36, CPT I, ACOX1 and LXRalpha of the LDLR-/- mice were significantly changed compared to the WT mice. The genes may be of some relevance to the complicated lipid metabolism network, and have effect in the early stage of atherogenesis. Show less

The work was aimed to investigate the differential expressions of lipid metabolism related genes in the early stage of atherosclerosis in the young apolipoprotein E deficient (apoE(-/-)) mice at different ages with normal chow diet. The genotypes of mice were identified by using multiplex polymerase chain reaction (multi-PCR) analysis. The semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and real-time quantitative RT-PCR were used to analyze the expressions of lipid metabolism related genes in the liver of apoE(-/-) and age-matched wild type (WT) mice of 14-day old, 1-month old, 2-month old, 3-month old. The serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) contents were assayed using COD-PAP and GPO-PAP methods. The serum apolipoprotein B100 (apoB100) content was quantitated by immune turbidimetry. The hearts were perfusion-fixed in 4% formaldehyde, infiltrated with 30% gum sucrose for 24 h at 4 °C, and embedded in OCT compound. The aortic sinus tissues were serially sectioned at -15 °C, stained with Sudan IV, and counterstained with light green. The results were shown as follows. Compared with that in WT mice, the mRNA levels of apoA I and apoA IV in apoE(-/-) mice aged from 14-day old to 3-month old changed prominently (P<0.05), with apoA I up-regulated and apoA IV down-regulated. At the age of 1 month, the expression of apoB100 in apoE(-/-) mice was higher than that in WT mice (P<0.05). The expression of apoA V was up-regulated (P<0.05) and there was obvious lipid deposition in the aortic intima in apoE(-/-) mice at the age of 2 months. The expressions of fatty acid translocase (Fat/CD36) and angiopoietin-like protein 3 (Angptl 3) in apoE(-/-) mice were higher than those in WT mice at the age of 3 months (P<0.05), while the expressions of peroxisome proliferator-activated receptor α (PPARα), liver X receptor α (LXRα), carnitine palmitoyl transferase I (CPT I) and acyl coenzyme A oxidase 1 (ACOX1) showed no significant changes. The serum TC, TG, LDL-C and HDL-C contents in apoE(-/-) mice aged from 14-day old to 3-month old were higher than those in age-matched WT mice. apoE(-/-) mice showed a marked increase in serum apoB100 content, consistent with the trend of serum LDL-C content and apoB100 mRNA content in the liver. The results suggest that the mRNA expressions of apoA I, apoA IV, apoA V, apoB100 and Angptl 3 in apoE(-/-) mice change significantly compared with those in WT mice, and these genes might be relevant to the complicated lipid metabolism network, and involved in the early stage of atherogenesis. Show less

To explore the relationship between the expression characteristics of lipid metabolism-related genes in the liver and early atherosclerotic lesions in apolipoprotein E and low density lipoprotein receptor gene double knockout (apoE(-/-)/LDLR(-/-)) mice. RT-PCR was used to detect the differential expression of lipid metabolism-related genes in the liver of apoE(-/-)/LDLR(-/-) and wild type (WT) mice. Serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) level as well as aortic morphology were also analyzed. Among the 11 lipid metabolism-related genes, apolipoprotein B100 (apoB100) mRNA levels were significantly higher in apoE(-/-)/LDLR(-/-)mice compared with WT mice. At 14 days, 1, 2 and 3 months of age, the level of mRNA expression were 1.55, 1.47, 1.50 and 2.42 folds of those of the age matched WT mice respectively. The fatty acid transporter (FAT/CD36) mRNA expression levels were higher in 14-day and 3-month old mice at 1.30 and 1.35 folds of those of the age matched WT mice, respectively. Apolipoprotein A IV (apoA IV) and Apolipoprotein AV (apoAV) mRNA levels were significantly down-regulated (0.89 fold decrease in 14-day, and 0.90 folds decrease in 3-month, respectively). The mRNA expression levels of apolipoprotein AI (apo AI), apolipoprotein F (apo F), peroxidase proliferator-activated receptor alpha (PPAR-alpha), liver X receptor alpha (LXRalpha), angiopoietin-like protein 3 (ANGPTL3), acyl-coenzymeA oxidase 1 (ACOX1) and carnitine palmitoyl transferase 1 (CPT1) had no significant changes. Serum TC, TG and LDL-C were higher than those of age matched WT mice at 7, 2 and 30 folds, respectively. Furthermore, apoE(-/-)/LDLR(-/-) mice demonstrated typical early atherosclerotic lesions at sinus and root regions of aorta in an age dependent manner. Alterations of the expression of lipid metabolism-related genes in liver play important roles in the development of AS in the apoE(-/-)/LDLR(-/-) mice at early ages. Show less

To investigate the association between the -1131T/C and 56C/G polymorphism in the APOA5 gene as well as the -482C/T in the APOC3 gene and susceptibility to coronary artery disease (CAD) in a Chinese Han population. Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and polyacrylamide gel electrophoresis (PAGE) methods, we analyzed the genotypes in 312 CAD patients diagnosed by angiography and 317 healthy controls. The levels of serum lipid profiles were also studied by biochemical methods. The frequency of the APOA5 -1131 C allele in CAD patients was significantly higher than that of the control group (39.9% vs. 33.3%, P = 0.02). Compared with the wild type TT, CC homozygotes had a significantly increased CAD risk (OR = 1.93 and OR = 1.80 using unadjusted and adjusted logistic regression models, respectively). This association still existed after adjustment for the APOC3-482 variant. The APOA5-1131C allele also showed a correlation with increasing plasma TG levels (P < 0.01). The APOA5-1131T/C polymorphism but not APOC3-482C/T might contribute to an increased risk of CAD among Chinese accompanied by an elevation of serum TG levels; this effect was found to be independent of the APOC3-482C/T variant. Show less

The disorder of triglyceride (TG) metabolism leading to hypertriglyceridemia is an independent risk factor for coronary artery disease (CAD). Variants in the newly identified apolipoprotein APOA5 gene were found to be strongly associated with elevated TG levels in different racial groups. In this study, we investigated the phenotypic effects of two polymorphisms (APOA5-1131T>C and APOC3-482C>T) on susceptibility to CAD in 312 Chinese CAD patients diagnosed by angiography. The frequency of the APOA5-1131C allele in these patients was significantly higher than that of the control group (39.9 vs. 33.3%, P=0.02). Compared with the wild type TT, CC homozygotes had a significantly increased CAD risk (OR=1.93 and OR=1.80 using unadjusted and adjusted logistic regression models, respectively). This association still existed after adjustment for the APOC3-482 variant. The APOA5-1131C allele also showed a correlation with increasing plasma TG levels (P<0.001). These data suggest that the APOA5-1131T>C polymorphism might contribute to an increased risk of CAD among Chinese as a result of its effect on TG metabolism; this effect was found to be independent of the APOC3-482C>T variant. Show less