Wo Yan-bo, Zhu Dan-yan, Hu Ying, Wang Zhi-Qiang, Liu Jian, Lou Yi-Jia
Institute of Pharmacology & Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.
J Cell Biochem. 2008 Apr 1;103(5):1536-50. doi: 10.1002/jcb.21541.
The significant promoting effects of some prenylflavonoids on cardiac differentiation of mouse embryonic stem (ES) cells via reactive oxygen species (ROS) signaling pathway were investigated. The most effective differentiation was facilitated by icariin (ICA), followed by icaritin (ICT), while desmethylicaritin (DICT) displayed the weakest but still significant inducible effect. Contrarily, DICT demonstrated the strongest anti-oxidative activity while ICA displayed only little in vitro, which was well matched with the hydroxyl (OH) numbers and the positions in the molecular structures. Therefore, ROS signaling cascades were assumed to be involved in prenylflavonoids induced cardiomyogenesis. Treatment with ICA, intracellular ROS in embryoid bodies was rapidly elevated, which was abolished by the NADPH-oxidase inhibitor apocynin; elimination of intracellular ROS by vitamin E or pyrrolidine dithiocarbamate (PDTC) inhibited ICA induced cardiomyogenesis; ROS-sensitive extracellular-regulated kinase 1, 2 (ERK1, 2) and p38 activation were further observed, the cardiomyogenesis was significantly inhibited in the presence of ERK1, 2 or p38 inhibitor U0126 or SB203580, indicating the roles of NADPH-ROS-MAPKs signaling cascades in prenylflavonoids induced cardiac differentiation. There was no difference in Nox4 NADPH oxidase expression between ICA and ICT treatments, however, ROS concentration in EBs after ICT administration was lower than that after ICA treatment, followed by less activation of ERK1, 2, and p38. These results revealed that the significant promoting effects of prenylflavonoids on cardiac differentiation was at least partly via ROS signaling cascades, and the facilitating abilities preferentially based on the nature of prenylflavonoids themselves, but anti-oxidative activity determined by the OH numbers and the positions in the structures do influence the cardiomyogenesis in vitro.
研究了一些异戊烯基黄酮类化合物通过活性氧（ROS）信号通路对小鼠胚胎干细胞（ES）心脏分化的显著促进作用。淫羊藿苷（ICA）促进分化的效果最为显著，其次是淫羊藿次苷（ICT），而去甲基淫羊藿次苷（DICT）的诱导作用最弱，但仍具有显著效果。相反，DICT表现出最强的抗氧化活性，而ICA在体外仅表现出微弱的抗氧化活性，这与分子结构中的羟基（OH）数量和位置相匹配。因此，推测ROS信号级联参与了异戊烯基黄酮类化合物诱导的心肌生成。用ICA处理后，胚状体中的细胞内ROS迅速升高，这被NADPH氧化酶抑制剂夹竹桃麻素消除；维生素E或吡咯烷二硫代氨基甲酸盐（PDTC）消除细胞内ROS抑制了ICA诱导的心肌生成；进一步观察到ROS敏感的细胞外调节激酶1、2（ERK1、2）和p38激活，在存在ERK1、2或p38抑制剂U0126或SB203580的情况下，心肌生成显著受到抑制，表明NADPH-ROS-MAPKs信号级联在异戊烯基黄酮类化合物诱导的心脏分化中起作用。ICA和ICT处理之间Nox4 NADPH氧化酶表达没有差异，然而，ICT给药后EBs中的ROS浓度低于ICA处理后，随后ERK1、2和p38的激活较少。这些结果表明，异戊烯基黄酮类化合物对心脏分化的显著促进作用至少部分是通过ROS信号级联实现的，促进能力优先基于异戊烯基黄酮类化合物本身的性质，但由结构中的OH数量和位置决定的抗氧化活性确实会影响体外心肌生成。
