肿瘤坏死因子α-308基因多态性与血液透析患者内瘘血栓形成的关系

Association between gene polymorphisms of tumor necrosis factor α-308 and thrombosis in internal arteriovenous fistula in patients with maintenance hemodialysis

目的探讨肿瘤坏死因子α(TNF-α)-308多态性与血液透析患者动静脉内瘘狭窄的易感性和血栓形成的关系。方法选取因动静脉内瘘血栓形成而住院治疗的100例透析患者为血栓组,100例内瘘狭窄患者为狭窄组,同期行动静脉内瘘成形术且未发生内瘘狭窄形成透析患者100例为对照组,应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)对TNF-α-308进行基因分型,同时测定三组患者的TNF-α和血栓前状态分子标志物水平。结果血栓组的低密度脂蛋白胆固醇(LDL-C)、TNF-α、血管性血友病因子(v WF)、血小板α颗粒膜蛋白-140(GMP-140)、纤维蛋白原(FIB)、D-二聚体(D-D)水平均明显高于狭窄组与对照组(t分别=2.39、11.22、6.06、4.24、10.65、7.71;2.68、12.22、7.13、5.94、13.55、10.37,P均<0.05),收缩压均明显低于狭窄组与对照组(t分别=2.46、3.30,P均<0.05),低分子肝素使用率明显低于对照组(χ~2=20.49,P<0.05)。经Pearson相关分析,血栓组TNF-α水平与v WF、GMP-140、FIB、D-D水平均呈明显正相关(r分别=0.73、0.64、0.78、0.66,P均<0.05)。进一步对TNF-α-308位点基因多态性分析发现,狭窄组与对照组的TNF-α-308位点GG、GA、AA基因型频率和G、A等位基因频率差异均无统计学意义(χ~2=0.31、0.37,P均>0.05),血栓组基因型、等位基因频率与狭窄组、对照组比较,差异均有统计学意义(χ~2=10.56、13.00、7.46、9.17,P均<0.05)。血栓组GG、GA基因型TNF-α、v WF、GMP-140、FIB、D-D水平均分别高于狭窄组、对照组GG、GA基因型,差异均有统计学意义(t分别=7.93、2.78、2.28、6.84、5.56、8.01、5.78、2.77、10.30、3.79、8.39、3.56、3.49、9.36、8.40、9.10、7.00、3.78、10.47、4.62,P均<0.05),血栓组AA基因型TNF-α、FIB、D-D水平均高于狭窄组、对照组(t分别=3.64、3.13、2.48、3.47、4.18、2.34,P均<0.05),狭窄组GA基因型FIB水平高于对照组(t=2.16,P<0.05),且内瘘血栓组TNF-α-308的GA+AA基因型比值比(OR)为4.00(95%CI:1.08~14.79);A等位基因OR为2.63(95%CI:1.54~4.51)。结论 TNF-α在内瘘血栓的发生、发展中起着重要作用;TNF-α-308位点GG、GA、AA基因型和G、A等位基因不是血液透析患者动静脉内瘘狭窄的易感因素;血液透析TNF-α-308GA、AA基因型携带者存在TNF-α表达明显增加和凝血、纤溶异常,呈较高的血栓前状态,较GG基因型患者更容易形成内瘘血栓。

Objective To investigate the association between the gene polymorphism-308 of tumor necrosis factor alpha（TNF-α）and the susceptibility to patients with fistula stenosis and thrombosis. Methods Totally 100 cases of thrombosis patients who hospitalized because of arteriovenous internal fistula thrombosis were selected as thrombosis group,100 cases of fistula stenosis patients enrolled as stenosis group,and 100 cases of thrombosis patients who underwent the arteriovenous internal fistula thrombosis surgery but did not occur the fistula stenosis were enrolled as the control group. The genotyping of TNF-α-308 were detected by PCR-RFLP,the level of TNF-α and the molecular markers of prethrombotic state were measured in all patients. Results The levels of low density lipid-cholesterol（ LDL-C）, TNF-α, von Willebrand factor（v WF）,platelet alpha granule membrane protein（GMP-140）,fibrinogen（FIB）and D-dimer（D-D）of patients with thrombosis group were significantly higher than those of stenosis group and control group（t=2.39,11.22,6.06,4.24,10.65,7.71,2.68,12.22,7.13,5.94,13.55,10.37,P〈0.05）.The systolic blood pressure was significantly lower than that of the stenosis group and the control group（t =2.46,3.30,P〈0.05）,and the utilization rate of low molecular weight heparin was lower than that of the control group（χ~2=20.49,P〈0.05）. The pearson analysis showed that the level of TNF-α in thrombosis group was positively related with v WF,GP-140,FIB and D-D（r=0.73,0.64,0.78,0.66,P〈0.05）. There were no significant differences in genotype frequency of GG,GA,AA and allele gene frequency of G,A between the stenosis group and control group（χ~2=0.31,0.37,P〉0.05）. However,the frequencies of these genotypes and alleles in patients with fistula thrombosis were significantly different with those in the fistula stenosis group and control group（χ~2=10.56,13.00,7.46,9.17,P〈0.05）.The TNF-α,v WF,GMP-140,FIB,and D-D levels of GG and GA genotype in thrombus group were significantly higher than those of GG,GA genotype in stenosis group and control group（t =7.93,2.78,2.28,6.84,5.56,8.01,5.78,2.77,10.30, 3. 79, 8. 39, 3. 56, 3. 49, 9.36,8.40,9.10,7.00,3.78,10.47,4.62,P〈0.05）. The TNF-α,FIB,D-D levels of AA genotype in thrombosis group were higher than those in the stenosis group and the control group（t=3.64,3.13,2.48,3.47,4.18,2.34,P 〈0.05）. The FIB level of GA genotype in stenosis group was higher than the control group（t=2.16,P〈0.05）. In the fistula thrombosis group,the odds ratio of GA＋AA genotype was 4.00（95% CI：1.08~14.79）; the odds ratio of A allele was 2.63（95% CI：1.54~4.51）. Conclusion TNF-α plays an important role in the development of fistula thrombosis. But TNF-α-308 G/A polymorphism is not associated with arteriovenous fistula stenosis in patients with hemodialysis. The GA and AA genotype of TNF-a-308 carrier has higher TNF-αexpression and abnormal coagulation and fibrinolysis,which are more likely to form a fistula thrombosis compared with the GG genotype carrier.