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|本期目录/Table of Contents|

缺氧前、后处理1-磷酸鞘氨醇对心肌细胞缺氧/复氧损伤拮抗作用的差异及相关机制

《心脏杂志》[ISSN:1009-7236/CN:61-1268/R]

期数:
2014年第1期
页码:
6-9020
栏目:
基础研究
出版日期:
2013-12-02

文章信息/Info

Title:
Difference and mechanism of S1P-mediated protection against hypoxia/reoxygenation induced cardiomyocyte injury between pre- and post-hypoxia treatment
作者:
张富洋; 周 芬; 闫文俊; 王 瀚; 陶 凌
(第四军医大学西京医院心血管内科，陕西 西安 710032)
Author(s):
ZHANG Fu-yang;  ZHOU Fen;  YAN Wen-jun;  WANG Han;  TAO Ling
(Department of Cardiology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi, China)
关键词:
1-磷酸鞘氨醇; 心肌细胞; 缺氧/复氧损伤; S1P裂解酶; 乳鼠
Keywords:
sphingosine-1-phosphate;  neonatal rat ventricular myocytes;  hypoxia/reoxygenation injury;  S1P lyase;  suckling rat
分类号:
Q54
DOI:
-
文献标识码:
A
摘要:
目的:探讨1-磷酸鞘氨醇（S1P）缺氧前、后处理对心肌细胞缺氧/复氧(H/R)损伤拮抗作用的差异及相关机制。方法:分离SD乳鼠（1~2 d龄）心肌细胞进行体外培养。对培养的心肌细胞进行H/R处理以模拟心脏缺血/再灌注（ischemia/reperfusion，I/R）损伤。将培养的心肌细胞随机分为对照组、H/R组、H/R+S1P缺氧前处理（H/R+pre-S1P）组及H/R+S1P缺氧后处理（H/R+post-S1P）组，采用四甲基偶氮唑蓝（methyl thiazolyl tetrazolium，MTT）比色法检测心肌细胞的活力，乳酸脱氢酶（lactate dehydrogenase，LDH）检测试剂盒检测培养基中LDH的水平，caspase-3活性检测试剂盒检测心肌细胞中caspase-3的活性，Western blot检测ATP激活的蛋白激酶(AMPK)、激活的苏氨酸激酶(Akt)、细胞外信号调节激酶1/2(ERK1/2)蛋白磷酸化水平及S1P裂解酶-1（S1P lyase 1，SPL1）蛋白表达的水平。结果:与对照组相比，H/R组心肌细胞活力显著降低（P<0.01），培养基中LDH的浓度和细胞中caspase-3的活性显著增高（P<0.01）。S1P缺氧前处理可明显增加H/R处理后心肌细胞的活力（P<0.01），减少LDH释放和caspase-3的活性（P<0.01）；而H/R+post-S1P组的各项指标与H/R组比较均无明显差异。Western blot检测发现，S1P缺氧前处理可明显增高心肌细胞中AMPK、Akt和ERk1/2磷酸化的水平（P<0.05），而S1P缺氧后处理未激活AMPK、Akt和ERK1/2生存信号。Western blot检测发现，缺氧处理组心肌细胞中SPL1表达的水平较对照组显著升高(P<0.01)。结论:缺氧前用S1P处理可激活AMPK、Akt、ERK1/2生存信号，显著减少心肌细胞凋亡，增加细胞的存活率，减轻心肌细胞H/R损伤；而S1P缺氧后处理不能发挥以上保护作用，其机制可能是缺氧处理导致心肌细胞SPL1的表达上调，通过降解S1P而减弱了其介导的抗心肌细胞H/R损伤的作用。
Abstract:
AIM:To investigate the difference of sphingosine-1-phosphate (S1P)-mediated protection against hypoxia/reoxygenation (H/R) induced cardiomyocyte injury between pre- and post-hypoxia treatment and the mechanism(s) involved. METHODS: Neonatal rat ventricular myocytes (NRVMs) were isolated from 1- to 2-day-old Sprague Dawley (SD) rats and were subjected to 9 h of hypoxia followed by 3 h of reoxygenation. After pre- or post-hypoxia treatment with 1 μmol/L S1P, cell viability was detected by MTT assay. LDH release and caspase-3 activity were detected by assay kits. AMPK, Akt and ERK1/2 phosphorylation levels and S1P lyase 1(SPL1) expression levels were analyzed by Western blot. RESULTS: In cultured NRVMs, pre-hypoxia treatment with 1 μmol/L S1P increased AMPK, Akt and ERK1/2 phosphorylation levels (all P<0.05) increased cell viability and reduced LDH release and caspase-3 activity after H/R (all P<0.01). However, post-hypoxia treatment with 1 μmol/L S1P failed to upregulate AMPK, Akt and ERK1/2 phosphorylation levels and lost its cardioprotective effects compared with those in H/R group. SPL1 expression level in NRVMs increased after hypoxia treatment (P<0.01). CONCLUSION: Pre-hypoxia treatment with S1P, but not post-hypoxia treatment, exerts strong protective effects against H/R injury in NRVMs by decreasing apoptosis. Pre-hypoxia treatment with S1P activates AMPK, Akt and ERK1/2 survival signaling pathway, whereas post-hypoxia treatment with S1P fails to achieve these effects. The mechanisms may be that hypoxia-induced SPL1 upregulation dismisses the protective role of S1P against H/R induced cardiomyocyte injury.

参考文献/References

[1]Louis MB,Priya W.Unresolved issues in myocardial reperfusion injury[J].Cardiovasc Pathol,2010,19(1):29-35.
[2]Michael M,Kuzhuvelil BH,Sheldon M,et al.Sphingosine-1-phosphate signaling and its role in disease[J].Trends Cell Biol,2012,22(1):50-60.
[3]Julie DS,Timothy H.Point-counterpoint of sphingosine-1-phosphate metabolism[J].Cir Res,2004,94(6):724-734.
[4]Ludovic G,Melanie P,Megan P,et al.A novel role for mitochondrial sphingosine-1-phosphate produced by sphingosine kinase-2 in PTP-mediated cell survival during cardioprotection[J].Basic Res Cardiol,2011,106(6):1341-1353.
[5]Graeme IL,Mark AF.Adiponectin sphings into action[J].Nat Med,2011,17(1):37-38.
[6]Takao K,Hideaki T,Koichi S,et al.Mechanism and role of high density lipoprotein-induced activation of AMP-activated protein kinase in endothelial cells[J].J Biol Chem,2010,285(7):4387-4397.
[7]Andrea H,Florence B,Nataliya K,et al.A prokaryotic S1P lyase degrades extracellular S1P in vitro and in vivo:implication for treating hyperproliferative disorders[J].PLoS ONE,2011,6(8):e22436.
[8]Padmavathi B,Norman H, Guanying W,et al.S1P lyase:a novel therapeutic target for ischemia-reperfusion injury of the heart[J].Am J Physiol Heart Circ Physiol,2011,300(5):H1753-H1761.
[9]Noureddine N,Olivier D,Soumeya B,et al.Evidence for a role of sphingosine-1 phosphate in cardiovascular remodelling in Fabry disease[J].Eur Heart J,2010,31(1):67-76.
[10]Noriko K,Sei-Ichiro O,Shin-Ichiro T,et al.S1P3-mediated cardiac fibrosis in sphingosine kinase-1 transgenic mice involves reactive oxygen species[J].Cardiovasc Res, 2010,85(3):484-493.

备注/Memo

备注/Memo:
收稿日期：2013-05-24.通讯作者：陶凌，主任医师，主要从事糖尿病心肌损伤临床和基础研究 Email：lingtao2006@gmail.com 作者简介：张富洋，本科生 Email：plazhangfuyang@163.com
更新日期/Last Update: 2014-01-20