Lignan Glycosides from Gentianella acuta (Michx.) Hulten. and Their Protective Effects Against H2O2-Induced Apoptosis in H9c2 Cardiomyoblasts

Two new lignan glycosides named acutosides A (1) and B (2) have been isolated from the whole plant of Gentianella acute (Michx) Hulten. and their structures were determined as (-)-(7R,8S,7'E)-4-hydroxy-3,3'dimethoxy-7,4'-epoxy-8,5'-neolign-7'-ene-9,9'-diol 9'-ethyl ether-4-O-β-D-glucopyranoside and (-)-(7R,8S,7'E)4-hydroxy-3,3'-dimethoxy-7,4'-epoxy-8,5'-neolign-7'-ene-9,9'-diol 9-ethyl ether-9'-O-β-D-glucopyranoside by means of 1D-, 2D-NMR, HR-ESI-MS, CD techniques and chemical reactions. Along with the above two new compounds we have obtained six known ones: (7R,8S)-dehydrodiconiferyl alcohol-4,9'-di-O-β-Dglucopyranoside (3), alaschanisoside A (4), citrusin A (5), 8,4',9'-trihydroxy-3,3'-dimethoxy-9,7'-epoxylignan 4O-β-D-glucopyranoside (6), leptolepisol D (7) and acanthoside D (8). The cardioprotective effects of compounds 1-8 were evaluated by measuring the viability of the compounds 1-8 pretreated H9c2 cardiomyoblasts after exposure to H2O2-induced apoptosis, the results showed that compounds 1, 3, 6 and 8 which could increase cell viability >15% at 200 μM had remarkably protective influence against H2O2-induced apoptosis. All the compounds were tested for cytotoxicity against two human tumor cell lines: gastric cancer SGC-7901 and breast cancer MCF-7. But they were inactive (IC50>40 μM).