Kozanecka Weronika, Mrówczyńska Lucyna, Pospieszny Tomasz, Jasiewicz Beata, Gierszewski Mateusz
Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland.
Department of Cell Biology, Faculty of Biology, A. Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland.
Steroids. 2015 Jun;98:92-9. doi: 10.1016/j.steroids.2015.03.003. Epub 2015 Mar 14.
New gramine connections with bile acids (lithocholic, deoxycholic, cholic) and sterols (cholesterol, cholestanol) were synthesized. The structures of products were confirmed by spectral (NMR, FT-IR) analysis, mass spectrometry (ESI-MS) as well as PM5 semiempirical methods. Unexpectedly, the products of the reaction of gramine with cholesterol and cholestanol were symmetrical compounds consisting of two molecules of sterols connected by N(CH3)2 group. All new synthesized compounds interact in vitro with the human erythrocyte membrane and alter discoid erythrocyte shape inducing stomatocytosis or echinocytosis. Increase in the incorporation of the fluorescent dye merocyanine 540 (MC540) into the erythrocyte membrane indicates that new compounds at sublytic concentrations are capable of disturbing membrane phospholipids asymmetry and loosening the molecular packing of phospholipids in the bilayer. Gramine significantly decreases the membrane partitioning properties as well as haemolytic activity of lithocholic acid in its new salt. Moreover, both deoxycholic and cholic acids completely lost their membrane perturbing activities in the gramine salts. On the other hand, the capacity of new gramine-sterols connections to alter the erythrocyte membrane structure and its permeability is much higher in comparison with sterols alone. The dual effect of gramine on the bile acid and sterols cell membrane partitioning activity observed in our study should not be neglected in vivo.
合成了新的禾草碱与胆汁酸（石胆酸、脱氧胆酸、胆酸）和甾醇（胆固醇、胆甾烷醇）的连接物。通过光谱（核磁共振、傅里叶变换红外光谱）分析、质谱（电喷雾电离质谱）以及PM5半经验方法确定了产物的结构。出乎意料的是，禾草碱与胆固醇和胆甾烷醇反应的产物是由通过N(CH3)2基团连接的两个甾醇分子组成的对称化合物。所有新合成的化合物在体外与人红细胞膜相互作用，并改变盘状红细胞的形状，诱导口形细胞增多症或棘形细胞增多症。荧光染料部花青540（MC540）掺入红细胞膜的增加表明，亚溶血浓度的新化合物能够扰乱膜磷脂的不对称性，并使双层中磷脂的分子堆积松弛。禾草碱显著降低了其新盐中石胆酸的膜分配特性以及溶血活性。此外，脱氧胆酸和胆酸在禾草碱盐中完全失去了它们的膜扰动活性。另一方面，与单独的甾醇相比，新的禾草碱-甾醇连接物改变红细胞膜结构及其通透性的能力要高得多。在我们的研究中观察到的禾草碱对胆汁酸和甾醇细胞膜分配活性的双重作用在体内不应被忽视。
