Shiraz University of Medical Science, Shiraz, Iran.
DANA Brain Health Institute, Irainian Neuroscience Society-Fars Chapter, Shiraz, Iran.
Exp Physiol. 2022 Aug;107(8):813-824. doi: 10.1113/EP089371. Epub 2022 Jul 5.
What is the central question of this study? Exercise training increases adropin and nitrite/nitrate (NOx) plasma levels in middle-aged and older healthy people. We hypothesized that high-intensity interval training may improve blood pressure and flow-mediated dilatation through the effects of adropin and NOx in patients of this age with type 2 diabetes. What is the main finding and its importance? High-intensity interval training may be more effective than moderate-intensity continuous training in improving endothelial function, blood pressure and flow-mediated dilatation through its effects on adropin and NOx in patients with type 2 diabetes.
Adropin is a newly identified bioactive protein that is important in energy hemostasis and vascular endothelial function. Lower levels of adropin in patients with type 2 diabetes are related to coronary atherosclerosis, characterized by impaired flow-mediated dilatation (FMD). The purpose of the present study was to investigate FMD and plasma levels of adropin and nitrite/nitrate (NOx) in patients with type 2 diabetes at baseline and follow-up after 12 weeks of high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT). Sixty-six persons with type 2 diabetes were divided into HIIT, MICT, and control groups. The HIIT group intervention was 12 intervals (1.5 min) at 85-90% maximal heart rate (HR ) separated by 2 min at 55-60% HR in three sessions per week for 12 weeks. MICT training consisted of 42 min of cycling at 70% HR . Before and after the intervention, FMD was recorded with high-resolution Doppler ultrasound. Plasma levels of adropin and NOx were measured by enzyme-linked immunosorbent assay. After training FMD was significantly higher in the MICT and HIIT groups compared to the control group (P < 0.05). Plasma levels of adropin and NOx were higher in both exercise groups, but the increase was greater in the HIIT group (P < 0.01). Peak oxygen consumption was increased after exercise training in both groups compared to the control group (P < 0.01). Percentage FMD showed a positive correlation with plasma levels of adropin and NOx (both P < 0.01), and a negative correlation with diastolic blood pressure (r = -0.530, P = 0.035) and systolic blood pressure (r = -0.606, P = 0.013) in the HIIT group. The results indicate that HIIT improved FMD whilst increasing adropin, NOx and peak oxygen consumption. Increased plasma levels of adropin may contribute, in part, to blood pressure reduction by increasing nitric oxide production.
本研究的核心问题是什么？运动训练可增加中年和老年健康人群的血清中瓜氨酸、硝酸盐/亚硝酸盐（NOx）水平。我们假设高强度间歇训练（HIIT）可能通过瓜氨酸和 NOx 的作用改善 2 型糖尿病患者的血压和血流介导的扩张功能。主要发现及其重要性是什么？与中等强度持续训练（MICT）相比，HIIT 可能通过对瓜氨酸和 NOx 的作用更有效地改善 2 型糖尿病患者的内皮功能、血压和血流介导的扩张功能。
瓜氨酸是一种新发现的生物活性蛋白，对能量稳态和血管内皮功能很重要。2 型糖尿病患者瓜氨酸水平较低与冠状动脉粥样硬化有关，其特征为血流介导的扩张功能（FMD）受损。本研究旨在观察 12 周 HIIT 或 MICT 后 2 型糖尿病患者 FMD 及血清瓜氨酸、硝酸盐/亚硝酸盐（NOx）水平的变化。66 例 2 型糖尿病患者分为 HIIT 组、MICT 组和对照组。HIIT 组干预措施为每周 3 次，每次 12 个 1.5min 的间隔，间隔期内以 85-90%最大心率（HR）运动，以 55-60% HR 休息 2min；MICT 组以 70% HR 踏车运动 42min。干预前后应用高分辨率超声多普勒记录 FMD。采用酶联免疫吸附法检测血清瓜氨酸和 NOx 水平。与对照组相比，MICT 组和 HIIT 组 FMD 明显升高（P<0.05）。两组瓜氨酸和 NOx 水平均升高，但 HIIT 组升高更显著（P<0.01）。与对照组相比，两组运动训练后峰值摄氧量均升高（P<0.01）。HIIT 组 FMD 与血清瓜氨酸和 NOx 呈正相关（均 P<0.01），与舒张压（r=-0.530，P=0.035）和收缩压（r=-0.606，P=0.013）呈负相关。结果表明，HIIT 可改善 FMD，同时增加瓜氨酸、NOx 和峰值摄氧量。血清瓜氨酸水平升高可能部分通过增加一氧化氮的产生来降低血压。
