SMS高表达对细胞内和培养基中SM水平的影响

Influences of SMS Overexpression on Cellular and Medium SM Levels

为了研究神经鞘磷脂合成酶(SMS)活性与神经鞘磷脂(SM)代谢之间的关系,用SMS的同功酶(SMS1和SMS2)的表达载体(pCMV.sport 6-SMS1和pcDNA3.1-SMS2),瞬时转染HEK293细胞,通过薄层层析法测定神经鞘磷脂合成酶活性来检测SMS的表达水平,同时测定细胞和培养基中的SM浓度.结果显示,用pCMV.sport 6-SMS1转染细胞后与对照组相比,SMS表达水平提高65%,细胞内和培养基中的SM水平显著性升高(58%和46%,p<0.01);转染pCDNA3.1-SMS2后与对照组相比,SMS表达水平提高13%,细胞内和培养基中的SM水平显著性升高(33%和29%,p<0.05).实验结果表明,SM水平可被SMS1和SMS2调节.由于SM是冠心病和动脉粥样硬化的独立危险因子,因此本文研究结果有可能为冠心病和动脉粥样硬化的治疗提供新的靶点.

In order to study the relationship between sphingomyelin synthase （SMS） activity and sphingomyelin（SM） metabolism, we transfected HEK293 cells with SMS1 or SMS2, two isoforms and SMS, expression vector. The expression levels of SMS were monitored by SMS activity assay, and cellular and medium SM levels were determined by an established method. The results show that SMS1 overexpression significantly increased SMS activity （65%）, cellular and medium SM levels （58% and 46%, p 〈 0. 01, respectively） in comparison with control cells. Whereas, SMS2 overexpression also significantly increased SMS activity（ 13% ） and SM levels in the cells（33%, p 〈0.05） or in the medium（29%, p 〈0.05） in comparison with controls. The results show that SM levels can be regulated by SMS1 or SMS2, suggesting that the monitoring SMS activity could be an alternative approach to treat atherosclerosis.