[Analysis of the FABP2 gene Ala54Thr polymorphism in non-obese and obese Chinese].

OBJECTIVE: To investigate the fatty acid-binding protein 2 gene (FABP2) Ala54Thr polymorphism and its relationship to obesity in Chinese population. METHODS: Three hundred and ninety three subjects (272 non-obese and 121 obese individuals) from a population of Chinese Han nationality in Chengdu area were studied using PCR-restriction fragment length polymorphisms (PCR-RFLPs). Serum lipids were measured by enzymatic kits and apolipoproteins A I, A II, B100, C II, CIII and E were measured by the RID kits. RESULTS: The frequencies of Ala and Thr allele at Ala54Thr site in obese and non-obese groups were 71.5%, 28.5%, and 71.1%, 28.9%, respectively. No significant difference in the allele frequencies between the two groups was observed (P > 0.05). In the obese group, subjects with Thr allele (AlaThr +ThrThr genotype carriers)had higher serum triglyceride (TG) concentrations than those with genotype AlaAla (P < 0.05). Similar results were observed in obese male subgroup, when male and female subgroups were further separated. In addition, obese males with AlaThr had lower HDL-C levels than those with genotype AlaAla. No significant difference of lipid and apolipoprotein levels was observed in obese females or non-obese group. CONCLUSION: The Ala54Thr polymorphism in the FABP2 gene was not associated with obesity in Chinese Han population of Chengdu area. However, it may be associated with serum TG, HDL-C levels, with some gender-specific effect, in this population.

[Antioxidants inhibit the oxidative modification of high density lipoproteins].

OBJECTIVE: To study the role and mechanism of antioxidants on inhibiting oxidative modification of high density lipoproteins (HDL). METHODS: Freshly prepared human plasma HDL was treated by incubation with copper ion, hyperchlorite or arterial wall cells. Compared to control, the test groups were treated with addition of different concentration of butylhydroxytoluene (BHT), vitamin C and vitamin E. Then, the relative electrophoretic mobility (REM), thiobarbituric acid-reactive substances (TBARS), ratio of lysolecithin to lecithin (LPC/PC), and lipoprotein moieties were investigated. RESULTS: BHT, vitamin C and vitamin E can significantly inhibit the increasing REM, TBARS, LPC/PC ratio and lipoprotein variation that induced by copper ion and hyperchlorite and arterial wall cells. But these antioxidants act on different manner. CONCLUSION: BHT, vitamin C and vitamin E can inhibit the oxidative modification of HDL and hence could be potential nutrients to prevent atherosclerosis.

[Analysis of -3826A/G polymorphism in the promoter of the uncoupling protein-1 gene in Chinese non-obese and obese populations].

OBJECTIVE: To investigate the -3826A/G polymorphism in the promoter of the uncoupling protein-1 (UCP1) gene and its relations to obesity in Chinese population. METHODS: Three hundred and eighty-four subjects (257 non-obese and 127 obese individuals) from a population of Chinese Han nationality in Chengdu area were studied using polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLPs). Serum lipids were measured by enzymatic kits and apolipoproteins A I, A II, B100, C II, C III and E were measured by the RID kits. RESULTS: The frequencies of A and G alleles at -3826A/G site in obese and non-obese groups were 0.508 and 0.492, and 0.467 and 0.533, respectively. It showed no significant difference in allele frequencies between non-obese and obese groups (P > 0.05). In the obese group, subjects with genotype GG had higher serum apo B100 concentrations, and those with genotype AG had higher apo C II and apo C III levels, than those with genotype AA, respectively (P < 0.05). In non-obese male subgroup, subjects with genotype GG had lower serum HDL-C and apo A I levels than those with genotype AA, respectively (P < 0.05), whereas those with genotype AG had lower apo A II levels than those with genotype AA. In addition, in obese males with genotype GG had elevated apo B100 levels compared with those with genotype AA, whereas in obese females with genotype GG had decreased apo AI levels and genotype AG had increased apo C II and apo C III levels compared with those with genotype AG and AA, respectively (P < 0.05). CONCLUSION: -3826A/G polymorphism in the promoter of the uncoupling protein-1 gene was not associated with obesity in Chinese Han population of Chengdu area. It may be associated with serum HDL-C, apo A I and apo B100 levels in non-obese and/or obese subjects of certain genders.

Identification of a novel gene, MSAG, regulated by high levels of glucose and insulin.

Identification and characterization of novel genes involved in derangement of metabolisms of glucose and triglycerides are important in understanding the development of metabolic syndrome (MS) and atherosclerosis. Model rats with certain phenotypes of MS were fed a high-carbohydrate diet. The rat hepatic subtracted cDNA libraries were constructed and screened. A novel cDNA of full length was identified by screening of a human hepatic cDNA library with a mixture of probes of the differentially expressed fragments from the rat hepatic subtracted cDNA libraries. The corresponding gene of the cDNA was temporarily named metabolic syndrome-associated gene (MSAG). The predicted protein encoded by MSAG contains 110 amino acids and has a theoretical molecular weight of 11667.04 and an isoelectric point of 4.91. Compared with the housekeeping gene of beta-actin, MSAG had low transcription activity. However, the mRNA level of MSAG in HepG2 cells, a human hepatoma cell line, was significantly increased by glucose and decreased by insulin concentrations higher than physiological levels. These results suggest that MSAG may be involved in the metabolism and/or its regulation of glucose, the functioning of insulin under non-physiological conditions, and further in the development of metabolic syndrome.

[Polymorphism in beta2 adrenergic receptor gene in Chinese population with obesity].

OBJECTIVE: To investigate the variation of beta2 adrenergic receptor (beta2 AR) gene and its association with obesity in Chinese population. METHODS: The allele of beta2 AR gene at Arg16Gly and Gln27Glu sites were analysed with polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) in 396 people with Han nationality in Chengdu, among whom 126 had obesity. RESULTS: The allele frequencies of Arg and Gly at Arg16Gly site were 0.571 and 0.429 for the obese people, and 0.559 and 0.441 for the non-obese people, respectively. The allele frequencies of Gln and Glu at Gln27Glu site were 0.920 and 0.080 for the obese people, and 0.916 and 0.084 for the non-obese people, respectively. No significant differences were found in the genotype frequencies of the two sites between non-obese and obese people. The non-obese females and obese males with genotype Arg/Arg at Arg16Gly site had elevated serum TC and LDL-C levels compared with those who carried Arg/Gly or Gly/Gly (P < 0.05). The apoB100 levels increased in the non-obese females with genotype Arg/Arg and decreased in the obese females with Arg/Gly (P < 0.05 ). The apoA I and apoA II levels decreased in the obese and non-obese males with Arg/Arg (P < 0.05). CONCLUSION: The polymorphism in beta2AR gene at Arg16Gly and Gln27Glu is not associated with obesity in Chinese Han population. But they may have certain degree of gender-specific impact on serum TC, LDL-C and apolipoprotein levels.

[The -384A >C polymorphism of endothelial lipase gene promoter region in Chinese healthy normolipidemic and endogenous hypertriglyceridemic subjects].

OBJECTIVE: To investigate the effects of the -384A>C polymorphism in the promoter region of endothelial lipase (EL) gene on serum lipid and apolipoprotein levels in healthy normolipidemic (HTG) and endogenous hypertriglyceridemic (HTG) subjects. METHODS: Two hundred and fourteen healthy normolipidemic and 103 endogenous hypertriglyceridemic subjects from a population of Chinese Han nationality in Chengdu area were studied using restriction fragment length polymorphism (RFLPs). Serum lipids were measured by enzymatic kits and apolipoproteins AI, AII, B100, CII, CIII and E were measured by the radial immunadiffussion kits. RESULTS: The frequency of the C allele at the -384A>C site in EL gene in the population (0.178) was higher than that of Japanese population (0.119) and Japanese Americans (0.115) (P < 0.01 and P < 0.01), respectively. No significant difference between normolipidemic and HTG groups was found in both allele and genotype frequencies. In normal group, subjects of the C allele carriers (A/C and C/C genotype carriers) had a higher serum mean concentration of TC, LDL-C and nHDL-C when compared with those of genotype AA (5.23 +/- 0.74 mmol/L vs 4.93 +/- 0.74 mmol/L, P=0.025; 3.27 +/- 0.74 mmol/L vs 2.98 +/- 0.80 mmol/L, P=0.038; 3.81 +/- 0.73 mmol/L vs 3.49 +/- 0.85 mmol/L, P=0.031, respectively). Similar result was only observed in female subgroup when male and female subgroups were further separated. No significant changes of lipid and lipoprotein levels were observed in the polymorphism in HTG group. CONCLUSION: These results suggest that the -384A>C polymorphism in the promoter region of the endothelial lipase gene is associated with serum TC, LDL-C, and nHDL-C levels in healthy Chinese subjects in Chengdu area, but not associated with the lipid levels in the endogenous hypertriglyceridmic group.

Distribution and effect of apo A-IV genotype on plasma lipid and apolipoprotein levels in a Chinese population.

OBJECTIVES: Hypertriglyceridaemia has been recognized as an independent risk factor for the development of coronary heart disease. Apolipoprotein A-IV (apo A-IV) plays an important role in the metabolism of TG-rich lipoproteins and HDL. However, the role of the polymorphism of the apo A-IV gene in hyperlipidaemia remains to be fully determined. The impact of the genetic variant in the apolipoprotein A-IV gene on lipid risk factor profiles for coronary heart disease was examined in Chinese patients with type-IV hyperlipoproteinaemia (HTG) and in healthy control individuals. METHODS: We genotyped five polymorphisms in the apo A-IV gene (codon 9, codon 347, codon 360, 3'end VNTR and Msp I sites) by direct sequencing or RFLP analysis in a Chinese population. RESULTS: The genotype frequencies in our results were significantly different from those reported in Caucasians. The polymorphic sites of codon 347 and codon 360, that have been widely studied in Western populations, were not observed in our population. The frequency of the G allele at codon 9 in HTG subjects was higher than that in healthy controls (P < 0.05). Serum apolipoprotein A-I (apo A-I), triglyceride (TG) and low-density lipoprotein cholesterol (LDLC) levels were affected by genotypes of codon 9, Msp I and VNTR polymorphisms, respectively, with some sex-specific effects in the control or HTG group. CONCLUSION: These results suggest that codon 9, Msp I and VNTR polymorphisms in the apo A-IV gene are associated with type-IV hyperlipoproteinaemia in a Chinese population.

[Analysis of beta2-adrenergic receptor gene (beta2AR) Arg16Gly polymorphism in patients with endogenous hypertriglyceridemia in Chinese population].

OBJECTIVE: To investigate the Arg16Gly polymorphism of beta2-adrenergic receptor (beta2AR) gene and its association with endogenous hypertriglyceridemia (HTG) in Chinese population. METHODS: Three hundred and forty one subjects including 100 HTG patients and 241 healthy controls from a population of Chinese Han nationality in Chengdu area were studied using polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLPs). RESULTS: The frequencies of Gly allele at the Arg16Gly locus in combined group was 0.446, and were 0.427 and 0.490 in normal and HTG group, respectively. No significant difference was found in both allele and genotype frequencies between normal control and HTG group. The frequency of Gly allele at the Arg16Gly locus in beta2-adrenergic receptor gene in the population (0.446) was similar to that of Japanese (0.505), higher than that of American white(0.248), and lower than that of Polish population (0.633). In normal controls, subjects with genotype Arg/Arg had a higher concentration of serum TG and apoB100, and lower apoAII levels, when compared with those with genotypes Arg/Gly or Gly/Gly, respectively (vs. Arg/Gly for TG, vs. Gly/Gly for apoB100 and apoAII, respectively, P<0.05). In HTG group, subjects with genotype Arg/Arg had higher serum TC and low-density lipoprotein cholesterol levels when compared with those with Gly/Gly genotype (5.36+/-0.74 mmol/L vs. 4.77+/-1.07 mmol/L,P<0.05;3.03+/-0.70 mmol/L vs. 2.38+/-1.10 mmol/L,P<0.05). CONCLUSION: These results suggest that the Arg16Gly polymorphism in beta2-adrenergic receptor gene are not only associated with serum TG,apoB100 and apoAII levels in the healthy Chinese subjects in Chengdu area, but also with serum TC and low-density lipoprotein cholesterol levels in subjects with endogenous hypertriglyceridemia. The Arg16Gly polymorphism in beta2-adrenergic receptor gene may be associated with TG and/or cholesterol metabolism in Chinese Han population.

[Association of apolipoprotein A5 gene -1131T/C polymorphism with serum lipids and carotid intima-media thickness in patients with type 2 diabetes mellitus].

OBJECTIVE: To investigate the relationship between apolipoprotein A5 gene -1131T/C polymorphism and serum lipids levels and carotid intima-media thickness in patients with type 2 diabetes mellitus in a Chinese population in Chengdu. METHODS: The genotype and allele frequencies of apolipoprotein A5-1131T/C polymorphism were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and polyacrylamide electrophoresis (PAGE) methods. The serum lipids were measured with enzymatic kits in 154 type 2 diabetic patients and 206 normal people (control). The carotid intima-media thickness (IMT) of 116 type 2 diabetic patients was measured by B-mode ultrasonography. RESULTS: The allele frequencies of T, C in the diabetic patients were 0.721, 0.279, respectively, which were not significantly different from those of the normal controls (0. 760, 0. 240). Compared with the wild type TT, CC homozygote increased the risk of type 2 diabetes significantly (OR=2.432, 95% CI: 1.081-5.473). In the patients with type 2 diabetes, the serum triglyceride (TG) level and TG/HDL-C ratio were greater in those with TC and CC genotypes than those with TT genotype subjects (P<0.05). The normal people with TC genotype also had greater triglyceride levels and TG/HDL-C ratio than those with TT genotype. The diabetic patients with CC genotype had greater carotid IMT than those with TT genotype (P=0.08). CONCLUSION: The -1131T/C polymorphism in the apolipoprotein A5 gene may have an impact on serum triglyceride levels and TG/HDL-C ratio. People with homozygote CC have increased risk of type 2 diabetes. But more evidence is needed to prove its association with carotid IMT in patients with type 2 diabetes.

[Inhibitory effect of quercetin, rutin and puerarin on LDL oxidation induced by Cu2+].

OBJECTIVE: To evaluate the inhibitory effect of quercetin, rutin and puerarin on the LDL oxidation induced by Cu2+ and to investigate their action on the prevention and treatment of atherosclerosis. METHOD: The serum LDL was isolated by the one step density gradient ultracentrifugation. The LDL oxidation was induced by Cu2+ in vitro for different time periods. Quercetin, rutin and puerarin at 5 micromol x L(-1) were added respectively, as the experimental groups, 3 hours before oxidation. The oxidation of LDL in experimental and control groups was identified by measuring A234, REM, TBARS and protein carbonyls content, and the values were compared between the two groups. RESULT: (1) The values of A234, REM, TBARS and protein carbonyls formation increased gradually during LDL oxidation induced by Cu2+ in vitro. (2) During LDL oxidation induced by Cu2+ in vitro and incubation with each of quercetin, rutin and puerarin, the kinetic changes of A234, REM, TBARS and protein carbonyls formation showed lag phases of 2-6 h, 2 h and 2 h respectively, and the corresponding values for each of the agents treated group were reduced by 27.7%-49.6%, 24.1%-38.6%, 19.8%-34.3% and 36.4%-56.8%; 12.8%-39.3%, 15.7%-32.0%, 19.0%-28.1% and 12.8%-50.3%; and 3.3%-19.2%, 7.0%-22.5%, 19.5%-22.8% and 8.6%-47.0%, respectively. CONCLUSION: These results suggest that quercetin, rutin and puerarin can substantially inhibit LDL oxidation, and quercetin has antioxidation ability stronger than rutin and puerarin.

[Inhibitory effect of isorhamnetin and hesperidin on the oxidation of high-density lipoproteins (HDL) induced by Cu2+].

OBJECTIVE: To test the inhibitory effect of isorhamnetin and hesperidin on the HDL oxidation induced by Cu2+. METHODS: The serum HDL was isolated by the one step density gradient ultracentrifugation. The HDL oxidation was induced by Cu2+ in vitro for different length of periods. Isorhamnetin and hesperidin at 5 micromol/L, respectively, were added 3 h before the copper oxidation. The oxidation of HDL was measured by the levels of absorbance at 234 nm (A234), relative electrophoretic mobility (REM), thiobarbituric acid reactive substances (TBARS) and protein carbonyls content. RESULTS: (1) A234, REM, TBARS and protein carbonyls formation increased gradually after 2, 4, 6, 8, 12 and 24 h of HDL oxidation induced by CU2+ without treatment with isorhamnetin or hesperidin. (2) With the treatment of isorhamnetin or hesperidin, the kinetic changes of A234, REM, TBARS and protein carbonyls formation delayed 2-6 h and 2-4 h, respectively. Compared with the controls, the A234, REM, TBARS and protein carbonyls formation were reduced by 16.3%-46.9% (P < 0.001), 0.6%-25.2% (P < 0.05), 9.2%-28.4% (P < 0.01) and 11.6%-45.2% (P < 0.001) by isorhamnetin and by 1.5%-30.0%, 1.4%-13.3%, 6.6%-18.8% (P < 0.05) and 14.4%-62.0% (P < 0.001) by hesperidin, respectively. CONCLUSION: Both isorhamnetin and hesperidin inhibit the oxidation of HDL, but isorhamnetin functions stronger.

[Inhibitory effect of Isorhamnetin and Hesperidin on LDL oxidation induced by Cu2+].

OBJECTIVE: To evaluate the inhibitory effect of Isorhamnetin and Hesperidin on the LDL oxidation induced by Cu2+. METHODS: The serum LDL was isolated by the one step density gradient ultracentrifugation. The LDL oxidation was induced by Cu2+ in vitro for different time periods. Isorhamnetin and Hesperidin at 5 micromol/L were added respectively, as the experimental groups, 3 hours before oxidation. The oxidation of LDL in experimental and control groups was identified by measuring A234 , REM, TBARS and protein carbonyls content. RESULTS: The values of A234, REM, TBARS and protein carbonyls formation increased gradually during LDL oxidation induced by Cu2+ in vitro. During LDL oxidation induced by Cu2+ in vitro and incubation with each of Isorhamnetin and Hesperidin, the kinetic changes of A234 , REM, TBARS and protein carbonyls formation showed lag phases of 2-4 h and 2 h respectively, and the corresponding values for each of the agents treated group were reduced by 23.5%-40.4%, 20.5%-37.7%, 18.6-30.3% and 20.1%-52.4% (P < 0.001); and 11.1%-21.2%, 9.2%-28.3%, 13.7%-21.3% and 5.0%-43.8% respectively (P < 0.001, P < 0.01, P < 0.001 and P < 0.05). CONCLUSION: It suggests that Isorhamnetin and Hesperidin can substantially inhibit LDL oxidation, and Isorhamnetin has antioxidation ability stronger than Hesperidin.

[Association between cholesterol 7alpha-hydroxylase -204A/C gene polymorphism and endogenous hypertriglyceridemia in Chinese].

OBJECTIVE: To investigate the cholesterol 7alpha-hydroxylase gene -204A/C polymorphism and its relationship with serum lipids and apolipoproteins (apo) levels in patients with endogenous hypertriglyceridemia (HTG) in Chinese population in Chengdu area. METHODS: The genotype and allele frequencies of cholesterol 7alpha-hydroxylase gene -204A/C polymorphism were analyzed by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Serum lipids were measured by enzymatic kits and apolipoproteins AI, AII, B100, CII, CIII and E were measured by the RID kits in 132 HTG patients and 212 control subjects. RESULTS: Allele frequencies of A and C were 0.602 and 0.398 in HTG group and 0.601 and 0.399 in control group, respectively. There was no significant difference of allele and genotypes frequencies between HTG and control groups (P> 0.05). In HTG group, carriers with the genotypes CC and AC were associated with significantly higher concentrations of triglycerides and apoCIII compared with those with genotype AA (P< 0.05). In the control group, carriers with the genotypes CC and AC were associated with significantly lower serum high density lipoprotein cholesterol (HDL-C) level compared with those with genotype AA (P< 0.05). In the male control group, carriers with the genotypes CC and AC had elevated levels of serum triglycerides than those with genotype AA (P< 0.05). CONCLUSION: These results suggest that -204A/C polymorphism in the CYP7A1 gene does not relate with HTG but may has an effect on serum triglyceride and apoCIII levels in patients with endogenous HTG, the serum HDL-C level in control subjects and the serum TG level in male control subjects.

[Purification of human VLDL apolipoproteins by middle pressure liquid chromatography].

OBJECTIVE: To purify human VLDL apolipoproteins by middle-pressure liquid chromatography. METHODS: Human VLDLs were isolated by one step density ultracentrifugation. Delipided human VLDL was separated by Sephacryl S-200 molecular sieve chromatography. ApoE was purified by heparin Sepharose CL-6B affinity chromatography. ApoC I ,C II and C III were purified from apoC. fraction by DEAE-Sephacel ion exchange chromatography: RESULTS: Purified apoE, apoC I, apoC II and apoC III were obtained. SDS-PAGE and immunodiffusion tests indicated the isolated proteins were pure. CONCLUSION: We have established a purification procedure for human VLDL apolipoproteins with highly efficiency and simplicity by MPLC.

[Analysis of ATP binding cassette A1 gene R219K polymorphism in patients with endogenous hypertriglyceridemia in Chinese population].

OBJECTIVE: To investigate the variations of ATP binding cassette A1 (ABCA1) gene and its relation to endogenous hypertriglyceridemia (HTG) in Chinese population. METHODS: A total of three hundred and nine subjects (one hundred and nine endogenous hypertriglyceridemics and 200 healthy controls) from a population of Chinese Han nationality in Chengdu area were studied using restriction fragment length polymorphism (RFLP) amplified by polymerase chain reaction (PCR). RESULTS: The frequency of K allele at R219K site 0.472 and 0.436 in normal and HTG group, respectively. No significant difference between normal control and HTG group was found in both allele and genotype frequencies. In both normal and HTG groups, subjects with genotype KK had a higher serum mean concentration of high density lipoprotein-cholesterol (HDL-C) when compared with those with genotype RR, respectively (1.48+/-0.45 mmol/L vs 1.27+/-0.29 mmol/L, P<0.05; 1.07+/-0.30 mmol/L vs 0.87+/-0.19 mmol/L, P<0.05). In normal group, subjects with genotype RK had a lower triglyceride (TG) level compared with those with genotype RR (1.22+/-0.37 mmol/L vs 1.41+/-0.84 mmol/L, P<0.05). In addition, the subjects carrying K allele in HTG group had a decreased total cholesterol (TC)/HDL-C ratio compared with those with genotype RR (KK vs RK vs RR: 4.82+/-1.28 vs 5.42+/-1.62 vs 6.33+/-1.70, P<0.05). CONCLUSION: These results suggest that R219K polymorphism in ABCA1 gene is not only associated with serum HDL-C and TG levels in healthy Chinese subjects in Chengdu area, but also with HDL-C level and TC/HDL-C ratio in subjects with endogenous HTG.

[Analysis of cholesterol ester transfer protein gene Taq IB and -629 C/A polymorphisms in patients with endogenous hypertriglyceridemia in Chinese population].

OBJECTIVE: To investigate the variations of cholesterol ester transfer protein (CETP) gene and its relation to endogenous hypertriglyceridemia (HTG) in Chinese population. METHODS: One hundred and thirty-five endogenous hypertriglyceridemics and 214 healthy subjects from a population of Chinese Han nationality in Chengdu area were studied using restriction fragment length polymorphism (RFLPs) amplified by polymerase chain reaction (PCR). The polymorphic sites studied included Taq IB and -629 C/A polymorphism in CETP gene. RESULTS: The frequencies of B(2) allele at Taq IB site in normal group and HTG group were 0.418 and 0.382, respectively. The frequencies of A allele at -629 C/A site in the two groups were 0.479 and 0.489, respectively. No significant difference between normal control and HTG groups were found in both allele frequency of the two polymorphism. Linkage disequilibrium was observed between Taq IB and -629 C/A polymorphic sites (D'=0.881). In the normal control group, subjects with genotype B(2)B(2) of Taq IB site had a higher serum mean concentration of HDL-C and lower LDL-C when compared with that of genotype B(1)B(1) and B(1)B(2), respectively (both P< 0.05), while those with genotype CC of -629 C/A site had a lower LDL-C level and higher Apo A II level when compared with that of genotype AC (P< 0.01 and P< 0.05, respectively). The changes of the lipid and lipoprotein levels were only observed in normal male subjects when male and female groups were further separated. No significant changes of lipid and lipoprotein levels were observed in both polymorphism in HTG group. Combined genotype analysis of the two sites, subjects with genotype B(2)B(2)CC in normal controls had higher HDL-C levels but lower serum triglyceride (TG) when compared with B(1)B(1)CC. CONCLUSION: These results suggest that Taq IB and -629 C/A polymorphisms in CETP gene are associated with healthy control subjects to some extent in Chinese population, but not with endogenous hypertriglyleridemia in the population group.

Plasma very-low-density lipoprotein, low-density lipoprotein, and high-density lipoprotein oxidative modification induces procoagulant profiles in endogenous hypertriglyceridemia.

This study was to investigate whether oxidatively modified lipoproteins were associated with changes of pro- and anticoagulant profiles in hypertriglyceridemic subjects. Plasma VLDL, LDL, and HDL were isolated with the one-step density gradient ultracentrifugation method. The oxidation of the lipoproteins was identified. Prothrombin time (PT) and activated partial thrombplastin time (APTT), tissue plasminogen activator and plasminogen activator inhibitor-1, and platelet aggregation rate were determined with a reaction system consisting of mixed fresh normal plasma, in endogenous hypertriglyceridemic (HTG) patients, in in vitro modified lipoproteins from a normolipidemic donor, and in experimental rats. The results indicated that oxVLDL, oxLDL, and oxHDL occurred in the plasma of HTG patients. Compared with the control group, PT and APTT, incubated with plasma VLDL, LDL, or HDL from HTG patients, respectively, were significantly reduced, while platelet maximal aggregation rates were significantly higher (P < 0.05-0.01). Similar procoagulant profiles were observed in in vitro modified lipoprotein components and in rats with intrinsic hypertriglyceridemia as well. These results support our previous finding that LDL, VLDL, and HDL were all oxidatively modified in vivo in the subjects with HTG, and suggest that procoagulation state may result from the abnormal plasma lipoprotein oxidative modification in vivo.

[Construction and preliminary screening of a forward-subtracted cDNA library for differentially expressed genes in rat liver of prothrombotic state].

OBJECTIVE: To construct and preliminarily screen the forward-subtracted cDNA library of differentially expressed genes in rat liver of prothrombotic state (PTS). METHODS: The forward-subtracted cDNA library for differentially expressed genes in rat liver of PTS was constructed by suppression subtractive hybridization using cDNAs synthesized from mRNA of PTS rat as Tester and cDNAs from mRNA of control rat as Driver. The products from the last PCR amplification of suppression subtractive hybridization were inserted into a T/A plasmid vectors to transform the Escherichia coli JM109 cells. To produce the library, the transformed cells were incubated at 37 C overnight on a LB agar plate containing ampicillin (50 microg/ml), IPTG and X-gal. Forward-subtracted cDNA probes and reverse-subtracted cDNA probes were prepared by nested PCR amplification, which were labeled with HRP. Positive clones were selected by differential screening in which forward-subtracted and reverse-subtracted cDNA probes were separately hybridized with the membranes slot-blotted by plasmid DNAs amplified and isolated from the library. Inserts in the positive clones were submitted to DNA sequencing. Nucleic acid sequence homology search was performed against the GenBank DNA database (non-redundant, and non-mouse and non-human EST entries) using the Standard nucleotide-nucleotide BLAST [blastn] program via a network connection to the National Center for Biotechnology information. RESULTS: The forward-subtracted cDNA library for differentially expressed genes in rat liver of PTS was successfully constructed. Two differentially expressed cDNA fragments were found after preliminary screening. CONCLUSION: The forward-subtracted cDNA library for differentially expressed genes in rat liver of PTS was successfully constructed in the present study.

[The effect of high density lipoprotein and oxidized high density lipoprotein on some secretive functions of endothelial cells].

OBJECTIVE: To investigate the effect of high density lipoprotein and oxidized high density lipoprotein on the synthesis of NO, the activity of NOS, and the secretion of tPA and PAI-1 by cultured human umbilical vein endothelial cells (HUVEC). METHODS: With the 0. 01 mol/L PBS and N-HDL of 50 mg/L as control, OX-HDL of 5 mg/L,10 mg/L, 50 mg/L were co-incubated with HUVEC for 24 h in vitro. The levels of NO, the activity of NOS, and the levels of tPA and PAI-1 in the medium were detected after the incubation. RESULTS: Compared with the 0.01 mol/L PBS control, the synthesis of NO(P < 0.05) and the activity of NOS (P < 0.01) were significantly increased in the N-HDL group, but the change of tPA and PAI-1 displayed no statistical significance (both P > 0.05). In the OX-HDL group, the synthesis of NO and the activity of NOS were significantly decreased in a dose-dependent way; the PAI-1 activity(P < 0.05) was increased, but the secretion of tPA (P > 0.05) was not affected. CONCLUSION: N-HDL significantly increased the synthesis of NO and the activity of NOS secreted by HUVEC, but it had no influence on the generation of tPA and PAI-1. On the contrary, OX-HDL significantly decreased the synthesis of NO and the activity of NOS; it significantly increased PAI-1 activity, but had no effect on the secretion of tPA.