中山大学学报（医学科学版）
中山大學學報（醫學科學版）
중산대학학보（의학과학판）
JOURNAL OF SUN YAT-SEN UNIVERSITY(MEDICAL SCIENCES)
2010年
2期
190-194
,共5页
陈保林%蒙荣森%马跃东%熊肇军%张成喜%陈广琴%刘晨%董吁钢
陳保林%矇榮森%馬躍東%熊肇軍%張成喜%陳廣琴%劉晨%董籲鋼
진보림%몽영삼%마약동%웅조군%장성희%진엄금%류신%동우강
心肌%蛋白水解%AMPK%FOXO3a%MAFbx
心肌%蛋白水解%AMPK%FOXO3a%MAFbx
심기%단백수해%AMPK%FOXO3a%MAFbx
myocardium%proteolysis%AMPK%FOXO3a%MAFbx
[目的]研究5-氨基-4甲酰胺咪唑核糖核苷酸(AICAR)对心肌细胞转录因子FOXO3a的活性以及泛素连接酶MAFbx蛋白表达的影响,探讨AMP激活的蛋白激酶(AMPK)在心肌细胞蛋白质降解中所起的作用.[方法]用不同浓度AICAR干预培养的新生大鼠心肌细胞6 h,观察AICAR对心肌细胞AMPK的激活作用.再将培养的心肌细胞分成3组:对照组,AICAR组,AICAR+Compound C组.用Western blot检测AMPK激活对心肌细胞FOXO3a转录因子活性,以及MAFbx蛋白表达的影响.[结果]①与对照组比较,0.25mmol/L与0.5mmol/LAICAR处理6 h后心肌细胞AMPK活性升高(P＜0.05),而1.0 mmol/L与2.0 mmol/L AICAR组AMPK活性增加更明显(P＜0.01).②与对照组比较,AICAR激活AMPK后显著增加FOXO3a转录活性(P＜0.01),促进MAFbx蛋白表达(P＜0.01),而特异性的AMPK抑制剂Compound C则明显抑制了该作用.[结论]AMPK可能通过激活心肌细胞FOXO3a的转录活性,上调MAFbx蛋白表达,参与心肌细胞蛋白质降解的调控.
[目的]研究5-氨基-4甲酰胺咪唑覈糖覈苷痠(AICAR)對心肌細胞轉錄因子FOXO3a的活性以及汎素連接酶MAFbx蛋白錶達的影響,探討AMP激活的蛋白激酶(AMPK)在心肌細胞蛋白質降解中所起的作用.[方法]用不同濃度AICAR榦預培養的新生大鼠心肌細胞6 h,觀察AICAR對心肌細胞AMPK的激活作用.再將培養的心肌細胞分成3組:對照組,AICAR組,AICAR+Compound C組.用Western blot檢測AMPK激活對心肌細胞FOXO3a轉錄因子活性,以及MAFbx蛋白錶達的影響.[結果]①與對照組比較,0.25mmol/L與0.5mmol/LAICAR處理6 h後心肌細胞AMPK活性升高(P＜0.05),而1.0 mmol/L與2.0 mmol/L AICAR組AMPK活性增加更明顯(P＜0.01).②與對照組比較,AICAR激活AMPK後顯著增加FOXO3a轉錄活性(P＜0.01),促進MAFbx蛋白錶達(P＜0.01),而特異性的AMPK抑製劑Compound C則明顯抑製瞭該作用.[結論]AMPK可能通過激活心肌細胞FOXO3a的轉錄活性,上調MAFbx蛋白錶達,參與心肌細胞蛋白質降解的調控.
[목적]연구5-안기-4갑선알미서핵당핵감산(AICAR)대심기세포전록인자FOXO3a적활성이급범소련접매MAFbx단백표체적영향,탐토AMP격활적단백격매(AMPK)재심기세포단백질강해중소기적작용.[방법]용불동농도AICAR간예배양적신생대서심기세포6 h,관찰AICAR대심기세포AMPK적격활작용.재장배양적심기세포분성3조:대조조,AICAR조,AICAR+Compound C조.용Western blot검측AMPK격활대심기세포FOXO3a전록인자활성,이급MAFbx단백표체적영향.[결과]①여대조조비교,0.25mmol/L여0.5mmol/LAICAR처리6 h후심기세포AMPK활성승고(P＜0.05),이1.0 mmol/L여2.0 mmol/L AICAR조AMPK활성증가경명현(P＜0.01).②여대조조비교,AICAR격활AMPK후현저증가FOXO3a전록활성(P＜0.01),촉진MAFbx단백표체(P＜0.01),이특이성적AMPK억제제Compound C칙명현억제료해작용.[결론]AMPK가능통과격활심기세포FOXO3a적전록활성,상조MAFbx단백표체,삼여심기세포단백질강해적조공.
[Objective]This study was designed to investigate the effects of 5-aminoimidasole-4-carboxamide ribonucleoside (AICAR)on activity of transcription factor Forkhead O 3a(FOXO3a)and expression of ubiquitin ligase muscle atrophy F-box (MAFbx),and to explore the role of adenosine monophosphate-activated protein kinase(AMPK)on proteolysis pathways in eardiomyocytes.[Methods]The effect of AICAR on activation of AMPK was observed.Cultured neonatal rat cardiomyocytes was treated with AICAR in different concentration.Cultured cardiomyocytes were then divided into three groups:control group,AICAR group,AICAR+Compound C group.Effects of AMPK activation on phosphorylation of FOXO3a and expression of MAFbx in cardiomyocytes were detected using Western blot.[Results]①Compared with control group,activity of AMPK in cultured cardiomyocytes was increased after treatment with 0.25 mmol/L or 0.5 mmol/L AICAR for 6 h(P＜0.05),and the activity of AMPK was further enhanced after treatment with 1.0 mmol/L or 2.0 mmol/L AICAR for 6 h(P＜0.01).②Activation of AMPK by AICAR significantly increased the transcriptional activity of FOXO3a(P＜0.01),and enhanced MAFbx protein expression in cardiomyocytes when comparing with control group(P＜0.01),however,specific AMPK antagonist Compound C markedly reversed these effects induced by AICAR.[Conclusion]AMPK may regulate cardiomyocytes proteolysis by activation of FOXO3a transcription factor,and up-regulation of MAFbx protein expression.
