口服谷氨酰胺对2型糖尿病患者血浆胰高血糖素样肽-1分泌的影响

Effect of oral glutamine on the secretion of plasma GLP-1 in patients with type 2 diabetes

目的:观察口服谷氨酰胺对2型糖尿病患者血浆胰高血糖素样肽-1(GLP-1)分泌的影响。方法:收集10例糖耐量异常者、10例病程<1年的2型糖尿病患者、10例病程≥1年而<5年的2型糖尿病患者、10例病程≥5而<10年的2型糖尿病患者、10例病程≥10年的2型糖尿病患者以及10例非肥胖健康个体作为研究对象。间隔1个月先后口服75 g葡萄糖及30 g谷氨酰胺,在服药前(0 min)及口服药物后30、60、90和120 min分别留血,检测血浆GLP-1、胰岛素以及血糖水平的变化。结果:口服75 g葡萄糖后,健康人及不同病程2型糖尿病患者的血浆GLP-1水平均升高,健康人的GLP-1分泌高峰在30 min(6.167 ng·ml-1),糖耐量异常者、病程<1年、病程≥1年而<5年、病程≥5年而<10年的2型糖尿病患者GLP-1的分泌高峰也在30 min(分别为4.195、3.706、3.794、3.000 ng·ml-1),病程≥10年的2型糖尿病患者GLP-1的分泌高峰在60 min(3.923 ng·ml-1)。口服30 g谷氨酰胺后,所有的受试者的血浆GLP-1的水平也均升高,健康人、糖耐量异常者以及病程<1年的2型糖尿病患者的GLP-1分泌高峰均在30 min(分别为5.488、3.719、3.718 ng·ml-1),病程≥1年而<5年、病程≥5年而<10年以及病程≥10年的2型糖尿病患者GLP-1分泌高峰在60 min(分别为3.667、2.399、2.368 ng·ml-1)。结论:不同病程的2型糖尿病患者存在不同程度的GLP-1分泌缺陷,口服葡萄糖刺激的GLP-1分泌峰值随糖尿病病程的增加呈下降趋势。口服30 g谷氨酰胺可以促进不同病程的2型糖尿病患者血浆GLP-1的分泌,并且不会影响2型糖尿病患者的血糖水平。谷氨酰胺通过促进2型糖尿病患者GLP-1的分泌,可能可以在2型糖尿病患者的血糖控制中发挥作用。

Objective： To observe the effect of oral glutamine on the secretion of plasma GLP-1 in patients with type 2 diabetes（ T2DM）. Methods： 10 cases of patients with impaired glucose tolerance（ IGT）,10 cases of patients with T2DM（ disease course 1 year）,10 cases of patients with T2DM（ 1 year≤disease course 5 years）,10 cases of T2DM（ 5 years≤disease course 10 years） and 10 cases of T2DM（ disease course ≥10 years） were recruited and 10 cases of non-obese healthy individuals were selected as the control group. Oral glucose（ 75 g） and glutamine（ 30 g） were administered on 2 separated days with one month interval,and the plasma GLP-1,GIP,insulin,glucagon and glucose levels were measured at baseline（ 0 min） and 30 min,60 min,90 min and 120 min after oral drugs. Results： After oral 75 g glucose,the plasma GLP-1 levels were increased in healthy people and patients with different course of T2 DM,the GLP-1 secretion peak was at 30 min（ 6. 167 ng · ml^-1） in healthy controls,which was also at 30 min（ 4. 195 ng·ml^-1,3. 706 ng·ml^-1,3. 794 ng·ml^-1,3. 000 ng·ml^-1） in patients with IGT,T2DM（ disease course 1 year）,10 cases of patients with T2DM（ 1 year ≤ disease course 5 years）,10 cases of T2DM（ 5 years≤disease course 10 years）,and at 60 min（ 3. 923 ng ·ml^-1） in T2 DM patients（ disease course≥10 years）. After oral 30 g glutamine,all the subjects＇ s plasma GLP-1 levels were also elevated,the GLP-1 secretion peak were all at 30 min of healthy controls,IGT patients and T2 DM patients（ disease course 1 year）（ 5. 488 ng·ml^-1,3. 719 ng·ml^-1,3. 718 ng·ml^-1）,while the GLP-1 secretion peak were all at 60 min of T2 DM patients（ 1 year≤disease course 5 years,5 years≤disease course 10 years,disease course≥10 years）（ 3. 667 ng·ml^-1,2. 399 ng·ml^-1,2. 368 ng·ml^-1）. Conclusion： Compared with healthy controls,IGT patients and T2 DM patients have different degrees of incretin secretion defect. After oral glucose,the GLP-1secretion peak level shows a descending trend accompany with diabetes＇ s duration increase. Oral 30 g glutamine can also stimulate GLP-1＇s secretion in different courses of type 2 diabetic patients. Glutamin may play a role in blood glucose control in patients with type 2 diabetes.