天津医药
天津醫藥
천진의약
TIANJIN MEDICAL JOURNAL
2014年
5期
447-450
,共4页
郭东%张闽红%肖清萍%刘建文
郭東%張閩紅%肖清萍%劉建文
곽동%장민홍%초청평%류건문
心肌梗死%成纤维细胞%细胞增殖%细胞分化%Smad7蛋白质%α平滑肌肌动蛋白%心脏重塑%micro RNA-21
心肌梗死%成纖維細胞%細胞增殖%細胞分化%Smad7蛋白質%α平滑肌肌動蛋白%心髒重塑%micro RNA-21
심기경사%성섬유세포%세포증식%세포분화%Smad7단백질%α평활기기동단백%심장중소%micro RNA-21
myocardial infarction%fibroblasts%cell proliferation%cell differentiation%Smad7 protein%α-SMA%cardiac remodeling%microRNA-21
目的：探讨小鼠心肌梗死模型中microRNA-21（miR-21）对心脏成纤维细胞增殖和分化的影响。方法利用左前降支结扎法构建小鼠心肌梗死模型（心肌梗死组），以心电图及病理改变作为建模成功的观察指标。采用荧光定量PCR检测各组心肌组织miR-21的表达。利用miR-21的模拟物（miR-21 mimic）转染小鼠成纤维细胞（miR-21 mimic组），使其在细胞中呈过表达状态，然后标记5-乙炔基-2′脱氧尿嘧啶核苷（EdU），通过荧光显微镜观察成纤维细胞的增殖情况，蛋白质印迹法检测成纤维细胞α平滑肌肌动蛋白（α-SMA）和小鼠Smad同源物7（Smad7）的表达，并与随机对照组及空白对照组比较。结果与假手术组比较，心肌梗死组梗死交界区的miR-21的表达量明显上调[（6.043±0.231）×10-4 vs（1.620±0.451）×10-4，P<0.01]，miR-21 mimic组成纤维细胞miR-21基因表达较随机对照组和空白对照组显著上调[（4.839±0.705）×10-4 vs（1.143±0.064）×10-4 vs（1.017±0.201）×10-4，P<0.01]，miR-21 mimic组成纤维细胞EdU染色阳性率较随机对照组和空白对照组显著增加[（27.892±1.645）%vs（12.553±1.227）%vs （13.946±1.550）%，P<0.01]；同时，miR-21 mimic组成纤维细胞Smad7蛋白的表达明显下调，而α-SMA的表达显著上调。结论心肌梗死后，上调的miR-21可以通过调节转化生长因子（TGF）-β信号通路中Smad7的表达促进成纤维细胞的增殖和分化，进而调节心梗后的心脏重塑。
目的：探討小鼠心肌梗死模型中microRNA-21（miR-21）對心髒成纖維細胞增殖和分化的影響。方法利用左前降支結扎法構建小鼠心肌梗死模型（心肌梗死組），以心電圖及病理改變作為建模成功的觀察指標。採用熒光定量PCR檢測各組心肌組織miR-21的錶達。利用miR-21的模擬物（miR-21 mimic）轉染小鼠成纖維細胞（miR-21 mimic組），使其在細胞中呈過錶達狀態，然後標記5-乙炔基-2′脫氧尿嘧啶覈苷（EdU），通過熒光顯微鏡觀察成纖維細胞的增殖情況，蛋白質印跡法檢測成纖維細胞α平滑肌肌動蛋白（α-SMA）和小鼠Smad同源物7（Smad7）的錶達，併與隨機對照組及空白對照組比較。結果與假手術組比較，心肌梗死組梗死交界區的miR-21的錶達量明顯上調[（6.043±0.231）×10-4 vs（1.620±0.451）×10-4，P<0.01]，miR-21 mimic組成纖維細胞miR-21基因錶達較隨機對照組和空白對照組顯著上調[（4.839±0.705）×10-4 vs（1.143±0.064）×10-4 vs（1.017±0.201）×10-4，P<0.01]，miR-21 mimic組成纖維細胞EdU染色暘性率較隨機對照組和空白對照組顯著增加[（27.892±1.645）%vs（12.553±1.227）%vs （13.946±1.550）%，P<0.01]；同時，miR-21 mimic組成纖維細胞Smad7蛋白的錶達明顯下調，而α-SMA的錶達顯著上調。結論心肌梗死後，上調的miR-21可以通過調節轉化生長因子（TGF）-β信號通路中Smad7的錶達促進成纖維細胞的增殖和分化，進而調節心梗後的心髒重塑。
목적：탐토소서심기경사모형중microRNA-21（miR-21）대심장성섬유세포증식화분화적영향。방법이용좌전강지결찰법구건소서심기경사모형（심기경사조），이심전도급병리개변작위건모성공적관찰지표。채용형광정량PCR검측각조심기조직miR-21적표체。이용miR-21적모의물（miR-21 mimic）전염소서성섬유세포（miR-21 mimic조），사기재세포중정과표체상태，연후표기5-을결기-2′탈양뇨밀정핵감（EdU），통과형광현미경관찰성섬유세포적증식정황，단백질인적법검측성섬유세포α평활기기동단백（α-SMA）화소서Smad동원물7（Smad7）적표체，병여수궤대조조급공백대조조비교。결과여가수술조비교，심기경사조경사교계구적miR-21적표체량명현상조[（6.043±0.231）×10-4 vs（1.620±0.451）×10-4，P<0.01]，miR-21 mimic조성섬유세포miR-21기인표체교수궤대조조화공백대조조현저상조[（4.839±0.705）×10-4 vs（1.143±0.064）×10-4 vs（1.017±0.201）×10-4，P<0.01]，miR-21 mimic조성섬유세포EdU염색양성솔교수궤대조조화공백대조조현저증가[（27.892±1.645）%vs（12.553±1.227）%vs （13.946±1.550）%，P<0.01]；동시，miR-21 mimic조성섬유세포Smad7단백적표체명현하조，이α-SMA적표체현저상조。결론심기경사후，상조적miR-21가이통과조절전화생장인자（TGF）-β신호통로중Smad7적표체촉진성섬유세포적증식화분화，진이조절심경후적심장중소。
Objective To investigate the role of microRNA-21(miR-21) on cardiac fibroblast proliferation and dif-ferentiation in the mouse model of myocardial infarction. Methods The mouse model of myocardial infarction (MI) was es-tablished by ligation of the left coronary artery in male C57BL/6 mice(MI group). The echocardiographic assessment and his-tological evaluation were performed after ligation. The expression levels of miR-21 were measured by quantitative real-time PCR in the various myocardial tissues. The cardiac fibroblasts transfected with miR-21 mimic were over-expressed miR-21. The proliferation was assessed by immunostaining for 5-ethynyl-2’-deoxyuridine (EdU). Western blot assay was used to detect the expression ofα-SMA and Smad7 in the cardiac fibroblasts,and compared with control group and blank group. Results The expression of miR-21 was significantly increased in border area in MI group than that of sham group [(6.043 ± 0.231)×10-4 vs(1.620±0.451)×10-4,P<0.01]. There was a higher expression of miR-21 in miR-21 mimic group than that of control group and blank group [(4.839±0.705)×10-4 vs(1.143±0.064)×10-4 vs(1.017±0.201)×10-4,P<0.01]. The EdU positive rate was significantly higher in miR-21 mimic group than that of control group and blank group[(27.892±1.645)%vs(12.553 ± 1.227)% vs(13.946 ± 1.550)%,P<0.01]. The expression of α-SMA was significantly increased in miR-21 mimic group, while the expression of Smad7, a target gene of miR-21, was significantly decreased. Conclusion The over-expression of miR-21 in cardiac fibroblasts disrupts TGF-βsignaling pathway by reducing the expression of Smad7, which promotes the proliferation and differentiation of cardiac fibroblast, and finally regulates cardiac remodeling after myocardial infarction.
