AMPK與eNOS基因多形性和耐力運動表現之關聯

Abstract

運動、缺氧或肌肉收縮會導致腺苷單磷酸活化蛋白激酶（AMP-activated protein kinase, AMPK）活化而調控細胞代謝途徑之運作。AMPK能透過磷酸化內皮型一氧化氮合成酶 (endothelial nitric oxide synthase, eNOS) 產生一氧化氮 (nitric oxide, NO) 並經由下游路徑刺激葡萄糖吸收。AMPK或eNOS基因變異也可能會影響能量代謝調控，但目前與運動方面的相關研究極少數。目的：探討耐力型運動員PRKAA2 (rs857155)、eNOS G894T與eNOS intron 4 a/b基因型分佈和一般民眾是否有差異。方法：採集國內103位曾獲得全國性比賽前三名之耐力型運動員（游泳、划船、自行車、足球、橄欖球、網球等種類）及200位一般民眾之血液DNA檢體，以聚合酶連鎖反應-限制片段長度多形性 (PCR-RFLP) 進行PRKAA2 (rs857155) 基因型分析；eNOS intron 4 a/b以聚合酶連鎖反應 (PCR) 進行基因型分析；eNOS G894T以引子展延法 (primer extension) 於變性高效能液相層析系統 (denaturing high performance liquid chromatography) 進行基因型分析。最後以SPSS 12.0統計套裝軟體進行χ2-test，統計顯著定為α = .05。結果：網球及划船運動員帶有PRKAA2 (rs857155) C對偶基因者顯著高於對照組。eNOS intron 4 a/b基因型及對偶基因分佈頻率在優秀耐力型運動員 (aa/ab/bb＝2.9/26.2/70.9%；a/b＝16.0/84.0%) 與對照組間 (aa/ab/bb＝1.5/15.5/83.0%；a/b＝9.3/90.8%) 有顯著差異；男性優秀耐力型運動員與對照組之eNOS intron 4 a/b基因型及對偶基因分佈頻率亦有明顯差異；自行車及划船運動員帶有eNOS intron 4 a對偶基因者顯著高於對照組。eNOS intron 4 a/b與eNOS G894T之間有連鎖不平衡存在，優秀耐力型運動員帶有a對偶基因 (aa+ab) 與T對偶基因 (GT+TT) 分佈頻率顯著高於對照組。結論：eNOS intron 4 a/b基因多形性與耐力運動表現相關聯，可能是選拔優秀耐力型運動員的候選基因。AMPK can be activated by exercise, muscle contraction and hypoxia to regulate various cellular metabolic pathways. AMPK is able to stimulate glucose uptake in skeletal muscle by phosphorylating eNOS and increase NO production. Also, genetic variants of AMPK and eNOS may affect metabolic regulation. However, there were little studies connect AMPK and eNOS to exercise performance. Purpose: To investigate the difference of PRKAA2 and eNOS gene polymorphism in elite endurance athletes and healthy control group. Methods: 103 endurance athletes (swimming, rowing, cycle, soccer, rugby, and tennis) who had won third place and above in national competitions were as the experimental group. The control group was 200 healthy people drawn from Taiwanese general population. The genotype of PRKAA2 (rs857155) was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), the genotype of eNOS intron 4 a/b was determined by polymerase chain reaction (PCR), and the genotype of eNOS G894T was determined by primer extension with denaturing high performance liquid chromatography (DHPLC). Data were analyzed with SPSS software version 12.0. χ2-test was employed to evaluate the difference (α= .05). Results: The frequency of the PRKAA2 (rs857155) C allele was significantly higher in tennis and rowing athletes as compared to the controls. The distribution of eNOS intron 4 a/b genotype and allele frequencies was significantly different between the athletes (aa/ab/bb = 2.9%/26.2%/70.9%; a/b = 16.0%/84.0%) and the controls (aa/ab/bb = 1.5%/15.5%/83.0%; a/b = 9.3%/90.8%), this phenomenon was also seen in male athletes. There was also a significant difference between the cycle athletes and the controls as well as the rowing athletes and the controls, with more tennis and rowing athletes carrying the a allele. Significant linkage disequilibrium was found between eNOS intron 4 a/b and eNOS G894T. The frequency of the a allele (aa+ab) and the T allele (GT+TT) combination was significantly higher in the athletes than in the controls. Conclusion: eNOS intron 4 a/b is associated with endurance exercise performance, and it might be a candidate gene for searching elite endurance athletes.