胰岛素样生长因子1调节胃平滑肌细胞表达干细胞因子的ERKMAPK通路  

Insulin-like growth factor 1 regulates expression of stem cell factor through ERKMAPK signaling pathway in gastric smooth muscle cell

作　　者：宁月季[1] 张蔚[1] 成家飞[1] 李学良[1] 王美峰[1] 林琳[1] 

机构地区：[1]南京医科大学第一附属医院消化科,210029

出　　处：《中华医学杂志》2010年第34期2402-2406,共5页National Medical Journal of China

基　　金：国家重点基础研究发展“973”计划（2006CB503908）;江苏省自然科学基金（BK2008466）

摘　　要：目的 探讨胰岛素样生长因子1（IGF-1）调节胃平滑肌细胞（SMC）表达干细胞因子（SCF）的信号传导途径.方法 培养SD大鼠胃SMC,α-肌动蛋白免疫荧光鉴定,Western印迹、反转录-聚合酶链反应（RT-PCR）检测胃SMC表达SCF的变化情况：（1）IGF-1作用后;（2）IGF-1受体（IGF-1Rα）抗体阻断IGF-1R后;（3）PD-98059、LY-294002分别抑制丝裂原激活蛋白激酶的激酶（MEK）、磷脂酰激醇3激酶（PI3K）后.结果 在无血清培养条件下,SCF在大鼠胃SMC中少量表达,低剂量IGF-1（5和10μg/L）对SCF表达均无影响（均P〉0.05）;中、高剂量IGF-1（50、100、150 μg/L）诱导分别使SCF蛋白表达上调达2.79、5.51及5.35倍,mRNA表达上调达1.81、2.54及2.38倍（均P〈0.05）;且促进SCF合成的最高峰在第16小时（蛋白表达上调达2.36倍,mRNA表达上调达5.51倍,均P〈0.05）.IGF-1Rot抗体可抑制SCF合成,抑制作用呈浓度依赖性（均P〈0.05）.分别用PD-98059、LY-294002预处理SMC、再用IGF-1诱导,PD-98059能部分阻断SCF的表达（蛋白抑制率为23%,mRNA抑制率为48%,均P〈0.05）、LY-294002对SCF的表达无影响（P〉0.05）.结论 IGF-1可通过IGF-1R以时间和剂量依赖性方式诱导胃SMC产生SCF,且IGF-1诱导SCF的表达可能依赖于ERKMAPK信号传导通路.Objective To explore the effect and the intracellular signal transduction pathway of insulin-like growth factor 1 （IGF-1） on the expression of stem cell factor （SCF） in gastric smooth muscle cells （SMC）.Methods Gastric SMC from SD rats were cultured by enzymolysis and identified by α-actin immunofluorescence methods.Western blot and quantitative reverse transcription-polymerase chain reaction were used to examine the expression of SCF in gastric SMC：（1） The level of SCF after gastric SMC were cultured with IGF-1.（2） The level of SCF after IGF-1 receptor （IGF-1 Rα） monoclonal antibody were added.（3） Another SMC were pretreated with specific mitogen-activated protein kinase （MEK） inhibitor PD-98059 and phosphatidylinositol 3-kinase （PI 3-kinase） inhibitor LY-294002,and investigate expression of SCF in gastric SMC.Results A very low level of SCF was expressed in gastric SMC cultured in bovine serum free medium.A low concentration of IGF-1 （5 and 10 μg/L） had no effect on the expression of SCF （both P 〉 0.05）,but the expressions of SCF mRNA and protein increased in IGF-1 at a higher concentration （50,100 and 150 μg/L） （2.79,5.51 and 5.35-fold in protein respectively,1.81,2.54 and 2.38-fold in mRNA respectively,all P 〈 0.05）,and IGF-1 in 100 μg/L may be the effective final concentration （all P 〈 0.05）.The peak of SCF increment was at the 16th hour with IGF-1 （2.36-fold in protein,5.51-fold in mRNA,all P 〈0.05）.The expression of SCF could be inhibited by IGF-1 receptor monoclonal antibody in a dose-dependent manner （all P 〈 0.05）.The IGF-1-induced SCF expression was reduced significantly by a pretreatment of PD-98059 （23% in protein and 48% in mRNA,P 〈0.05）.And LY-294002 had no effect on the expression of SCF （P 〉 0.05）.Conclusion The SCF expression in gastric SMC is stimulated by IGF-1 in both dose-and time-dependent manners through IGF-1R in which ERKMAPK signal transduction may play an important role.

关 键 词：胰岛素样生长因子Ⅰ 干细胞因子 肌细胞 平滑肌 信号传导 

分 类 号：R587.2[医药卫生—内分泌] R573[医药卫生—内科学]