ObjectiveTo explore the differential expression of Sirtuin1 (SIRT1) in type A aortic dissection at diverse ages.MethodsThe expression of SIRT1 and monocyte chemoattractant protein-1 (MCP-1) in aortic tissue of the patients with type A aortic dissection (an aortic dissection group) and coronary heart disease (a control group) from 2019 to 2020 in the First Hospital of China Medical University was analyzed. In each group, the patients were divided into 3 subgroups according to the age (a younger subgroup, <45 years; a middle age subgroup, 45-60 years; an elderly subgroup, >60 years). The quantitative real-time PCR, Western blotting and immunochemical stainning were used to detect the mRNA or protein expression of SIRT1 and MCP-1. ResultsA total of 60 patients were included in each group, including 79 males and 41 females. There were 20 patients in the yonger, middle age and elderly subgroups for the two groups, respectively. Compared with the control group, the expression of SIRT1 mRNA decreased in the aortic dissection group (the younger subgroup: 4.54±1.52 vs. 8.78±2.57; the middle age group: 2.70±1.50 vs. 5.74±1.07; the elderly group: 1.41±1.33 vs. 3.09±1.14, P<0.001). Meanwhile, SIRT1 mRNA in the aortic dissection group declined with age (P<0.01). Compared with the control group, SIRT1 protein expression decreased significantly in the aortic dissection group (the younger group: 0.64±0.18 vs. 1.18±0.47; the middle age group: 0.43±0.26 vs. 0.69±0.32; the elderly group: 0.31±0.24 vs. 0.45±0.29, P<0.01). The Western blotting results showed that the expression of SIRT1 protein in the aortic dissection group decreased with age (P<0.01). The MCP-1 protein expression of younger and middle age patients in the aortic dissection group was increased compared with that in the control group (the younger group: 0.65±0.27 vs. 0.38±0.22; the middle age group: 1.08±0.30 vs. 0.46±0.36, P<0.001). MCP-1 expression increased with age (P<0.01). The result of immunohistochemical staining for SIRT1 protein was similar to that of Western blotting.ConclusionThe expression of SIRT1 decreases in patients with aortic dissection disease, and declines with age. SIRT1 may play an important role in the treatment and screening of type A aortic dissection.
Objective To investigate whether the agonist of delta opoid receptor D-Ala(2),D-Leu(5) enkephalin (DADLE) has the effect of decreasing myocardial injury during ischemia-reperfusion of adult rabbits’ myocardium，so that a new mehanism and way to myocardial protection could be found. Methods Langendorff model was used during the experiment. Thirty rabbits were divided into three groups randomly (each group 10 rabbits). Control group: St.Thomas Ⅱ cardioplegic solution was used; group 1: St.Thomas Ⅱ cardioplegic solution and DADLE (1mg/kg) were used; group 2: St.Thomas Ⅱ cardioplegic solution and naloxone(3mg/kg) were used to induce the hearts to arrest respectively. After arrest the hearts were reperfused respectively. Data of left ventricle development pressure(LVDP) was recorded before and after ischemia. Biochemical indicators of myocardium, lactate dehydrogenase(LDH) were detected before and after ischemia. Some myocardial tissues were used to explore the changes of the tissue of ultrastructure with electron microscope，when the experiment was over. Still some myocardial tissues were to be detected by flow cytometer to evaluate the apoptosis of the myocardium. Results The LDH and LVDP showed significant difference among three groups after ischemia(Plt;0.05); LVDP in group 1 was higher than those in group 2 and control group(69.8±5.8 mmHg vs. 23.4±3.9 mmHg; 69.8±5.8 mmHg vs. 37.9±4.7 mmHg; Plt;0.05), the LDH in group 1 was lower than those in group 2 and control group(1 272.6±59.1 U/L vs. 2 764.4±27.7 U/L, 1 272.6±59.1 U/L vs. 1 884.4±37.5 U/L; Plt;0.05). The apoptosis rate in group 1 was lower than those in group 2 and control group. As could be shown from the ultrastructure: mitochondria structure was nearly normal in group 1; mitochondria structure was injuried severely in group 2; there was a minor injury in control group. Conclusion Agonist of δ opoid receptor DADLE in cardioplegic solution could induce hibernation, which has myocardial protection effect during ischemia-reperfusion injury.