microRNA-31在β-氨基丙腈诱导的主动脉瘤/夹层小鼠主动脉中的表达

Expression of MicroRNA-31 in the Aorta Tissues of β-Aminopropionitrile Monofumarate-Induced Aortic Aneurysm and Dissection Mice

目的研究发现,microRNA-31(miR-31)可能在血管紧张素Ⅱ(AngⅡ)诱导的主动脉瘤/夹层小鼠的发病中起重要作用。本文探究了β-氨基丙腈(β-aminopropionitrile monofumarate,BAPN)诱导的主动脉瘤/夹层小鼠中miR-31的表达水平。方法选取3周龄的C57BL/6野生型雄性小鼠(n=40),随机分为BAPN组(n=20)和对照组(n=20),BAPN组小鼠饮用0.4%浓度BAPN的饮用水,对照组小鼠饮用普通饮用水,实验周期为28天。造模结束后测量小鼠的主动脉直径和血压,统计小鼠生存率和主动脉瘤/夹层发生率。分离两组小鼠主动脉组织并提取总RNA,应用加尾法、茎环法逆转录和实时定量PCR对比分析两组小鼠主动脉组织miR-31的表达水平。结果存活曲线显示BAPN组小鼠生存率显著降低(45%∶100%,P<0.01)。BAPN组小鼠主动脉瘤/夹层的发生率为75%,主动脉瘤/夹层破裂死亡率为55%。与对照组相比,BAPN组小鼠升主动脉最大直径[(1.86±0.51)mm比(1.18±0.11)mm,P<0.01]和主动脉弓最大直径[(1.95±0.50)mm比(1.16±0.17)mm,P<0.01)]显著大于对照组;两组之间收缩压[(101.20±5.26)mm Hg比(100.60±7.56)mmHg,P=0.891)]和舒张压[(59.40±9.94)mmHg比(62.00±5.76)mmHg,P=0.600)]差异无统计学意义。使用加尾法逆转录和实时定量PCR检测BAPN诱导的小鼠主动脉瘤/夹层主动脉组织中miR-31的表达水平,主动脉瘤/夹层主动脉组织中miR-31的表达水平对比对照组有升高趋势,但差异无统计学意义(1.11±1.41比1.00±1.26,P=0.686)。扩大样本量,使用茎环法逆转录和实时定量PCR检测小鼠主动脉组织miR-31的表达水平,BAPN诱导的主动脉瘤/夹层小鼠主动脉组织中miR-31表达水平对比对照组有升高趋势,但差异依旧无统计学意义(1.73±1.69比1.00±2.65,P=0.328)。结论BAPN诱导的主动脉瘤/夹层小鼠对比对照组小鼠主动脉组织中miR-31的表达水平有升高趋势,但无显著差异。基于miR-31在AngⅡ诱导产生的小鼠主动脉瘤/夹层中可能起到的重要作用,需要扩大样本量进一步探讨BAPN诱导对比AngⅡ诱导产生的小鼠主动脉瘤/夹层组织中miR-31表达水平的差异及意义。

Objective It has been reported that microRNA-31(miR-31)may play an important role in angiotensinⅡ(AngⅡ)-induced aortic aneurysm/dissection mice.The present study was aimed to explore the expression level of miR-31 in the aortic tissues ofβ-aminopropionitrile monofumarate(BAPN)-induced aortic aneurysm/dissection mice.Methods Three-week-old C57 BL/6 wild-type male mice(n=40)were randomly divided into BAPN group(n=20)and control group(n=20).The BAPN group mice were given the drinking water containing 0.4%BAPN while the control group mice were given the ordinary drinking water for 28 days.The aortic diameters and blood pressures of mice were measured after model construction.The survival rates and incidences of aortic aneurysm/dissection were counted.The aortic tissues of mice were separated,and total RNA was extracted.Poly(T)adaptor and stem-loop real-time quantitative PCR were used to detect the miR-31 expression level in aortic tissues between the BAPN-induced aortic aneurysm/dissection mice and the control group.Results The survival curve showed that the survival rate of mice in the BAPN group was significantly decreased(45%vs 100%,P<0.01).In the BAPN group,the incidences of aortic aneurysm/dissection and aortic aneurysm/dissection rupture were 75%and 55%respectively.The maximal aortic diameters of ascending aorta[(1.86±0.51)mm vs(1.18±0.11)mm,P<0.01]and aortic arch[(1.95±0.50)mm vs(1.16±0.17)mm,P<0.01]of the BAPN group were larger than the control group.No statistical difference was observed between the BAPN group and the control group in systolic blood pressure[(101.20±5.26)mmHg vs(100.60±7.56)mmHg,P=0.891]and diastolic blood pressure[(59.40±9.94)mmHg vs(62.00±5.76)mmHg,P=0.600].Compared with the control group,the expression level of miR-31 in aortic tissues of BAPN-induced aortic aneurysm/dissection mice had an increasing trend with no statistical difference detected by poly(T)adaptor real-time quantitative PCR(1.11±1.41 vs 1.00±1.26,P=0.686)and stem-loop real-time quantitative PCR(1.73±1.69 vs 1.00±2.65,P=0.328).Conclusion The expression level of miR-31 in aortic tissues of BAPN-induced aortic aneurysm/dissection mice had an increasing trend with no statistical difference compared with the control group.Based on the possible important role of miR-31 in aortic aneurysm/dissection mice induced by AngⅡ,the expression level of miR-31 in aortic tissues of BAPN-induced and AngⅡ-induced aortic aneurysm/dissection mice needs to be compared and explored using a larger sample size.