【摘要】 目的:探讨血浆脂蛋白上鞘氨醇-1-磷酸(S1P)和磷脂转运蛋白(PLTP)的相互作用及机制。方法:检测雄性10周龄PLTP转基因(PLTP-Tg)及野生型(WT)小鼠血浆S1P和脂蛋白上S1P含量,转运实验检测PLTP对S1P的转运作用,免疫印迹检测S1P载体载脂蛋白M(apoM)含量。结果:PLTP-Tg小鼠血浆S1P含量较WT小鼠下降21.1%(P<0.01),高密度脂蛋白(HDL)组分上S1P含量下降约35.1%,而低密度脂蛋白(LDL)组分上S1P比例则增加了127.4%。转运实验表明,在37℃时D-Hanks缓冲液中PLTP能够促进S1P从红细胞转运至重组脂质体。PLTP-Tg小鼠血浆中apoM含量与WT小鼠比较无变化。结论:生理水平PLTP对保持HDL上S1P含量有重要意义,过表达PLTP可显著降低HDL上S1P,同时升高LDL上S1P,其机制可能与PLTP介导S1P转运有关。更多还原

【Abstract】 AIM: To investigate the interaction and the mechanism of sphingosine-1-phosphate( S1P) and phospholipid transfer protein( PLTP) in lipoprotein. METHODS: The S1 P content in the plasma and lipoprotein from 10-week-old PLTP transgenic( PLTP-Tg) mice and wild-type( WT) mice( n = 8 each) was assayed. The transport of S1 P by PLTP was determined by S1 P transfer assay. The content of specific S1 P carrier,apolipoprotein M,was detected by Western blotting. RESULTS: Plasma S1 P contents were decreased by 21. 1% in PLTP-Tg mice compared with WT mice. S1 P content in high-density lipoprotein( HDL) fraction( HDL-S1P) from PLTP-Tg mice was decreased by 35. 1% compared with WT mice,whereas the S1 P in low-density lipoprotein( LDL) fraction( LDL-S1P) was increased by 127. 4%. The results of S1 P transfer assay indicated that PLTP facilitated S1 P transport from erythrocyte to recombinant liposome at 37 ℃ in D-Hanks buffer solution. The plasma content of apolipoprotein M was not changed in PLTP-Tg mice compared with WT mice. CONCLUSION: PLTP is a key factor to maintain plasma HDL-S1 P under physical condition. Overexpression of PLTP decreases the HDL-S1 P but increases LDL-S1 P. The mechanism might be related to the capability of PLTP on transferring S1 P from erythrocyte to lipoprotein.更多还原