对氧磷酯酶1基因多态性与Ⅱ型糖尿病合并冠心病

对氧磷酯酶(PON)是一种钙离子依赖性芳香酯酶，通过apoA Ⅱ紧密结合于HDL颗粒上，水解脂质过氧化物，防止LDL、HDL和DNA被氧化修饰，破坏ox—LDL中的溶血磷脂，具有心血管保护作用。PON基因是一个由PONl、PON2、PON3基因组成的多基因家族，研究表明PONl基因多态性Ⅱ型糖尿病合并大血管并发症的独立危险因素，分别是启动子区多态性、55位Met／Leu多态性(等位基因M/L)、192位Gln／Arg多态性(等位基因A／B)。     

屏氧酶1与ATP结合盒转运子A1基因多态性的相互作用对血脂的影响

目的探讨屏氧酶1(paranoxonase 1, PON1)基因多态性与ATP结合盒转运子A1基因(ATP-binding cassette transporter 1, ABCA1)多态性对血脂水平的相互作用.方法 1019例受试者,其中680例脑卒中患者及339名正常对照组人群.采用聚合酶链反应-限制性片段长度多态性方法测定 PON1 A/B192和 ABCA1 R219K基因多态性.结果 PON1 A/B192各基因型之间血脂水平差异无统计学意义(P>0.05).在 ABCA1的RR、RK和KK 3种基因型中,HDL-C水平依次明显上升(P<0.05);TG水平依次呈下降趋势,相互之间差异无统计学意义.PON1基因型影响 ABCA1基因型与血脂的关系,AA型/RR型和BB型/KK型的HDL-C[(1.41±0.40)mmol/L,(1.41±0.39)mmol/L]高于BB型/RR型[(1.28±0.36)mmol/L],差异有统计学意义(P<0.05).结论 PON1基因型与ABCA1基因型的相互作用影响血脂水平.     

Ⅱ型对氧磷酯酶基因311Cys/Ser多态性与2型糖尿病合并冠心病关系的研究

目的:探讨型对氧磷酯酶(PON2)基因311Cys/Ser遗传多态性与2型糖尿病合并冠心病的关系。方法:应用PCR-RFLP技术,对75例老年2型糖尿病患者,其中39例2型糖尿病者合并冠心病者,36例糖尿病对照者,和38例健康对照者,检测PON2-311Cys/Ser基因多态性,等位基因以C/S表示。结果:2型糖尿病合并冠心病组与健康对照组比较,各基因型分布有显著差异(P<0.05)。S等位基因在2型糖尿病合并冠心病组明显增高;S等位基因是2型糖尿病并发冠心病的危险因素(OR=2.09,95%CI:1.04-4.22,P<0.05)。结论:PON2基因311Cys/Ser遗传多态性与中国北方地区2型糖尿病并发冠心病发病具有相关性。该酶切位点多态性具有明显的种族差异。     

对氧磷酯酶1基因多态性与Ⅱ型糖尿病合并冠心病

对氧磷酯酶 (PON)是一种钙离子依赖性芳香酯酶 ,通过 apo A I紧密结合于 HDL 颗粒上 ,水解脂质过氧化物 ,防止L DL、HDL 和 DNA被氧化修饰 ,破坏 ox- L DL 中的溶血磷脂 ,具有心血管保护作用。PON基因是一个由 PON1、PON2、PON3基因组成的多基因家族 ,研究表明 PON1基因多态性是 型糖尿病合并大血管并发症的独立危险因素 ,分别是启动子区多态性、5 5位 Met/ L eu多态性 (等位基因 M/ L)、192位 Gln/ Arg多态性 (等位基因 A/ B)。     

细胞间黏附分子-1基因K469E多态性与广西壮族人群缺血性脑卒中的遗传易感性

目的探讨细胞间黏附分子-1(intercellular adhesion molecule-1, ICAM-1)基因多态性与广西地区壮族人群缺血性脑卒中(ischemic stroke,IS)的关系.方法采用聚合酶链反应-限制性片段长度多态性和DNA序列测定法检测205例IS及210名对照者 ICAM-1基因第6外显子K469E多态性,同时采用酶联免疫吸附试验检测IS和对照者血清ICAM-1水平. 结果 IS组ICAM-1血清水平显著高于对照组(P<0.01), ICAM-1基因K469E基因型频率和等位基因频率在IS组和对照组比较差异有统计学意义(P<0.05),等位基因频率的相对风险分析发现,E等位基因携带者患IS的风险是K等位基因的1.424倍(OR=1.424,95%CI1.071～1.894),携带E等位基因的IS患者ICAM-1血清水平显著高于不携带者[(501.24±139.56)ng/ml vs(475.17±118.35)ng/ml, P<0.01]. 结论 ICAM-1基因K469E多态性与IS的发病具有相关性,E等位基因可能是广西地区壮族人群IS发病的遗传易感基因,携带E等位基因的个体可能通过促进 ICAM-1的高度表达进而增加IS的发病风险.     

武汉汉族新生儿中肺表面活性物质蛋白D基因多态性及其与支气管肺发育不良相关性分析

目的: 研究武汉汉族新生儿中肺表面活性物质蛋白D(SP-D)基因多态性及其与支气管肺发育不良(BPD)易感性的相关关系。方法: 采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)对218例武汉汉族新生儿SP-D相关位点进行基因型检测,同时进行基因测序验证结果。结果: SP-D Met11Thr三种基因型TT、TC、CC频率分别为10.5%、49.1%、40.4%,等位基因T和C频率分别为35.1%和64.9%。SP-D Ala160Thr三种基因型GG、GA、AA频率分别为54.6%、39.4%、6.0%,等位基因G和A频率分别为74.3%和25.7%。与对照组比,SP-D Met11Thr和SP-D Ala160Thr基因多态性与BPD发生率无明显关联(P>0.05)。结论: SP-D Met11Thr和SP-D Ala160Thr基因型和等位基因频率存在种族差异性;SP-D Met11Thr和SP-D Ala160Thr基因多态性与BPD发生率无明显关联。     

ZNF230基因突变筛查及其与无精症的相关性分析

目的探讨 ZNF230基因与无精症的关系.方法应用变性高效液相色谱(denaturing high performance liquid chromatography,DHPLC) 对99例无精症患者与115名健康对照者基因组DNA中 ZNF230基因全部6个外显子进行突变筛查. 结果检测到 ZNF230基因第6外显子A316G碱基转换;无精症组与健康对照组之间等位基因频率和基因型频率均差异存在统计学意义(分别为P<0.01和P<0.05);无精症组内GG和GA基因型亚组血清卵泡刺激素水平明显高于AA基因型亚组(P<0.05). 结论 ZNF230基因不但可能和无精症相关,而且可能与血清FSH水平有一定相关性.     

凝血因子(ⅩⅢ)Val34Leu基因多态性与冠心病关系的研究

目的 :研究FVal34Leu基因多态性在汉族人群中的分布情况 ,并探讨其与冠心病及心肌梗死的关系。方法 :应用聚合酶链反应 -单链构像多态性技术检测 398例汉族人 (冠心病组 195例 ,对照组 2 0 3例 )的F基因Val34Leu突变基因型。结果 :Val/Val基因型和Val/Leu基因型频率分别为 95 2 %和 4 8% ,未发现Leu/Leu基因型 ,Leu等位基因频率为 2 4 %。冠心病组和对照组间基因型和等位基因频率无显著差异 (P >0 0 5 )。非心肌梗死组Val/Leu基因型和Leu等位基因分布频率显著高于心肌梗死组 (P <0 0 5 )。结论 :中国汉族人群中存在FVal34Leu基因多态性     

囊泡相关膜蛋白8基因多态性与冠状动脉粥样硬化性心脏病的相关性研究

目的 研究囊泡相关膜蛋白8(synaptobrevins/vesicle-associated membrane proteins 8,VAMP8)基因rs1010多态性在中国汉族人群中的分布及与冠状动脉粥样硬化性心脏病(简称冠心病)的相关性.方法 采用聚合酶链反应-限制性片段长度多态性技术,对汉族185例冠心病患者及149名正常人VAMP8 rs1010基因多态性,基因型及等位基因频率分布进行研究.结果 研究人群中存在VAMP8 rs1010基因多态性,基因型符合Hardy-Weinberg平衡,冠心病患者A等位基因频率显著高于对照组(67.3%VS 53.0%,P<0.05).Logistic回归分析得出:VAMP8基因(AA+AG)基因型是冠心病的独立危险因素,(AA+AG)基因型比GG基因型的比数比为1.969,95%可信区间为1.032～3.755.结论 VAMP8 rs1010基因多态性与冠心病有关,A等位基因可能是汉族人群冠心病的遗传危险因素.     

Ⅰ型二乙基对硝基苯磷酸酯酶基因多态性与冠心病

Ⅰ型二乙基对硝基苯磷酸酯酶(paraoxonase1,PON1)是一种广泛存在于人体血液中的多态性蛋白酶,它的两个遗传多态性位点55Leu→Met和192Gln→Arg均与冠心病发生之间存在某种相关性。由于PON1在血液中主要是与高密度脂蛋白相结合,而高密度脂蛋白缺乏被认为是粥样硬化发生的一个重要因素,且PON1能破坏氧化型低密度脂蛋白,对抗脂质过氧化,尤其是通过运用基因敲除术对小鼠实验动物模型的研究,已较肯定地证实PON1基因是冠心病发生的候选基因。     

Genetics of paraoxonase

Danish family material comprising 1664 unrelated individuals (parents) and 3169 children, as well as 699 grandparents of the same families, were examined for paraoxonase activity. A micro-autoanalyser method, comprising a primary testing in tris buffer at pH 7-5 and, in the case of primarily intermediate individuals, a secondary testing at pH 10, was applied. This gave a better discrimination than testing only at pH 7.5, because individuals around the low mode of the primary activity distribution had their pH optimum at pH 10, while the optimum of individuals around the high was at pH 8.5. By this combined testing all individuals could be unequivocally classified as 'low' or 'high', and the family material was compatible with the low phenotype representing homozygosity for an autosomal recessive gene with a frequency P_low= 0–726. Out of 5532 individuals, 5 showed an almost complete lack of paraoxonase activity.     

Serum paraoxonase 1 activity and oxidant/antioxidant status in Saudi women with polycystic ovary syndrome

Oxidative stress is considered to be implicated in the pathophysiology of polycystic ovary syndrome (PCOS). This study was designed to evaluate the paraoxonase 1 (PON1) activity and oxidant/antioxidant status in Saudi women with PCOS and its contribution to the risk of atherosclerosis.Lipid profile, hormonal parameters, serum PON1 activity and oxidant (malondialdehyde)/antioxidant (total antioxidant capacity (TAC) levels were analyzed in 35 patients with PCOS and 30 healthy controls using a spectrophotometric method; correlation analysis was made between these variables. Insulin resistance was calculated by homeostasis model assessment (HOMA-IR).Women with PCOS had significantly higher fasting insulin, HOMA-IR and LH levels than controls. Lipid profiles and free androgen index (FAI) were significantly higher in women with PCOS when compared with controls. Serum PON1 activity was lower in the PCOS group (161.2 ± 6.1 U/l vs. 217.6 ± 9.3 U/l, p < 0.001) compared with controls, whereas malondialdehyde levels were higher in the PCOS group (4.26 ± 0.18 nmol/ml vs. 1.37 ± 0.12 nmol/ml, p < 0.001) compared with controls. Total antioxidant capacity was lower in the PCOS group (0.88 ± 0.10 mmol Trolox/l vs. 1.63 ± 0.17 mmol Trolox/l, p < 0.001) compared with controls. In PCOS group, serum PON1 was positively correlated with HDL-C (r = 0.425, p < 0.05) and TAC (r = 0.582, p < 0.01) but inversely correlated with HOMA-R (r = ?0.54, p < 0.01), testosterone (r = ?0.672, p < 0.01), FAI (r = ?0.546, p < 0.01) and malondialdehyde (r = ?0.610, p < 0.01).In conclusion, our data indicate that PON1 activity and antioxidant status were significantly decreased in Saudi women with PCOS. Lower serum PON1 activity might contribute to the increased susceptibility for the development of atherosclerosis risk in Saudi women with PCOS. Therefore, measurement of serum PON1 activity may be of value in assessment of women at higher risk for development of atherosclerosis risk in PCOS. However, further studies with larger sample size are needed to verify these results, and to assess the efficacy of antioxidant therapy on these patients.     

Immobilization of paraoxonase onto chitosan and its characterization

Paraoxonase was covalently immobilized onto a glutaraldehyde containing amino group functionalized chitosan surface by chemical immobilization at pH 8.0. The amount of covalently bound hPON1 was found to be 32 mg/10 chitosan beads. The properties of immobilized enzyme were investigated and compared to those of free enzyme. The effects of various parameters such as pH, temperature, heat, and storage stability on immobilized enzyme were investigated. Kinetic parameters of the immobilized enzyme were also evaluated. Thermal and storage stability experiments were carried out. It was observed that the immobilized enzyme had longer storage stability and retained 50 % of its initial activity during 26 days.     

Linkage between the loci for cystic fibrosis and paraoxonase

In a material of 22 Danish, 26 Canadian, 10 Australian, 5 English and 5 American families with at least 2 children affected with cystic fibrosis (CF) a combined positive LOD score of 3.46 was found for the relationship cystic fibrosis-paraoxonase (PON) at recombination fraction theta = 0.07 in males and theta = 0.13 in females. Assuming a three allele model for PON the LOD score was 4.50 at the same recombination fractions. This confirms our earlier finding of an indication of CF-PON synteny.     

人芳香二烷基磷酸酯酶基因丛基因多态性快速分析法

目的建立一种人芳香二烷基磷酸酯酶（PON）基因丛等位基因快速分型法。方法在Multiplex-PCR-RELP基础上，通过引物设计错配，在一体系中同时扩增分别含PON1-192、PON1-55和PON2-31l位密码子的DNA片段，当等位基因为PON1-192R／PON1-55L／PON2-31lS时，PCR扩增产物中均被引入唯一的限制性内切酶HinfⅠ的识别位点G^＋ANTC。PCR扩增产物经酶消化，聚丙烯酰胺凝胶电泳后，相互分开的不同组合的片段，确认为不同的基因型组合，同时对3个位点进行基因分型。结果在检测的80例健康个体中，等位基因频率为PON1-192：Q46．9％．R53．1％：PON1-55：L95．6％，M4．4％；PON2-31l：S78．8％，C21．2％。结论此方法快速分析3个位点的基因多态性，省时省力、节约经费，便于3个位点之间的连锁分析，具有推广价值。     

Decreased paraoxonase activity in critically ill patients with sepsis

Paraoxonase 1 is believed to play a role in preventing lipid oxidation and, thus, limiting production of proinflammatory mediators. Systemic inflammatory response in sepsis increases oxidative stress and decreases high-density lipoprotein (HDL) concentrations. The objective of this study was to investigate serum paraoxonase 1 activities in critically ill patients with sepsis and after recovery. Serum paraoxonase 1 arylesterase/paraoxonase activities, concentration of total cholesterol, HDL cholesterol (HDL-C) and serum C-reactive protein (CRP) in septic patients of a medical intensive care unit (n = 30) and age/sex-matched outpatient controls without sepsis (n = 30) were analyzed. Paired convalescent samples were also taken 1 week after recovery (n = 11). In septic patients, both arylesterase (88.3 ± 36.5 vs. 162.1 ± 44.8 kU/l, P < 0.001) and paraoxonase (75.2 ± 50.0 vs. 125.2 ± 69.4 U/l, P < 0.01) paraoxonase 1 activities decreased as compared to controls. Both activities normalized after recovery. Negative correlation was found between CRP and both arylesterase (r = −0.676, P < 0.001) and paraoxonase (r = −0.401, P < 0.01) as well as positive correlation between HDL-C and both arylesterase (r = 0.585, P < 0.001) and paraoxonase (r = 0.405, P < 0.01) paraoxonase 1 activities. The decreased activity of paraoxonase 1 in negative correlation with CRP offers a potentially useful marker of sepsis progress and recovery in critically ill patients.     

Relationship between paraoxonase and homocysteine: crossroads of oxidative diseases

Homocysteine (Hcy) is an accepted independent risk factor for several major pathologies including cardiovascular disease, birth defects, osteoporosis, Alzheimer''s disease, and renal failure. Interestingly, many of the pathologies associated with homocysteine are also linked to oxidative stress. The enzyme paraoxonase (PON1) – so named because of its ability to hydrolyse the toxic metabolite of parathion, paraoxon – was also shown early after its identification to manifest arylesterase activity. Although the preferred endogenous substrate of PON1 remains unknown, lactones comprise one possible candidate class. Homocysteine-thiolactone can be disposed of by enzymatic hydrolysis by the serum Hcy-thiolactonase/paraoxonase carried on high-density lipoprotein (HDL). In this review, Hcy and the PON1 enzyme family were scrutinized from different points of view in the literature and the recent articles on these subjects were examined to determine whether these two molecular groups are related to each other like a coin with two different sides, so close and yet so different and so opposite.     

Time-dependent modulation of rat serum paraoxonase 1 activity by fasting

High-density lipoprotein-associated paraoxonase 1 (PON1) protects the endothelium from the pro-oxidant activity of oxidised low-density lipoprotein. Whereas fasting has been related to increased oxidative stress, intermittent fasting and caloric restriction are associated to increased resistance to oxidative injury. Taking into consideration that serum PON1 activity is modulated by a restriction of caloric intake and because there is no evidence regarding PON1 response to total food deprivation, we investigated whether PON1 activity is involved in the response aimed to counteract the greater oxidative stress associated to fasting and whether serum PON1 activity is altered by the length of food deprivation. Male Wistar rats were randomly divided into five groups: fed and 6-, 12-, 24- or 48-h fasted rats. Serum PON1 activity increases within the first hours of fasting, representing a prompt adaptation designed to attenuate blood lipid peroxidation that cannot be sustained when fasting is prolonged. This PON1 response to early fasting could be part of the mechanisms triggered by periodically repeated short periods of food deprivation—intermittent fasting—which result in increased resistance to stress by stimulating antioxidant defences.     

Serum paraoxonase and arylesterase activities in patients with pulmonary tuberculosis

Background: The aim of the present study was to determine serum paraoxonase and arylesterase activities in tuberculosis, nontuberculosis pulmonary disease and healthy subjects. Materials and methods: In this case-control study we determined the serum paraoxonase and arylesterase activities in 36 patients with pulmonary tuberculosis, 38 nontuberculosis pulmonary disease and 49 healthy controls. Results: The results showed that serum paraoxonase (PON) activity was significantly lower in patients with pulmonary tuberculosis (61.10 ± 51.62 IU/L) than healthy controls (98.79 ± 68.79 IU/L) (p < 0.05). In addition we found that the level of PON activity was significantly lower in patients with nontuberculosis pulmonary disease (67.49 ± 47.88 IU/L) than normal individuals (p < 0.05). There was no significant differences regarding PON activity between patients with pulmonary tuberculosis and nontuberculosis pulmonary disease (p > 0.05). The arylesterase activity was significantly lower in patients with pulmonary tuberculosis than nontuberculosis pulmonary disease and normal subjects (p < 0.05). Discussion: The lower paraoxonase and aryesterase activities in pulmonary tuberculosis patients compared to healthy subjects might be due to imbalance of oxidant/antioxidant systems in pulmonary tuberculosis patients which needs more clarification.