黄芩苷PEG-PCL纳米胶束的体外评价、细胞内分布及抗心肌细胞凋亡的研究

Study on in Vitro Evaluation,Intracellular Distribution and Anti-apoptosis of Baicalin PEG-PCL Nanomicelle

目的评价黄芩苷PEG-PCL纳米胶束的细胞内分布及抗心肌细胞凋亡作用。方法采用薄膜水化法制备黄芩苷PEG-PCL纳米胶束,以香豆素-6作为荧光探针,评价PEG-PCL纳米胶束在细胞内的摄取及细胞内分布;采用10μmol·L^-1异丙肾上腺素诱导H9c2心肌细胞凋亡进行造模,将等剂量黄芩苷和黄芩苷PEG-PCL纳米胶束在造模前预处理1h,测定细胞凋亡相关的caspase 3活性、ROS水平,Bcl-2和Bax蛋白的表达水平。结果黄芩苷PEG-PCL纳米胶束具有粒径小,释药缓慢等优良特点;荧光试验表明,PEG-PCL纳米胶束能促进药物的细胞摄取,还能将药物聚集在线粒体部位,细胞凋亡试验结果表明,黄芩苷PEG-PCL能显著降低凋亡相关的caspase 3活性、ROS水平,降低促凋亡Bax的表达,明显提高抗凋亡Bcl-2的表达,这些结果均与等剂量的黄芩苷存在显著性差异。结论黄芩苷PEG-PCL纳米胶束能促进黄芩苷被心肌细胞摄取,有助于将药物聚集在线粒体部位,从而很大程度上提高药物抗心肌细胞凋亡作用。

OBJECTIVE To evaluate the intracellular distribution and anti-cardiomyocyte apoptosis effect of baicalin PEG-PCL nanomicelle.METHODS Baicalin PEG-PCL nanomicelle were prepared by membrane hydration method.Coumarin-6 was used as a fluorescent probe to evaluate the uptake and intracellular distribution of PEG-PCL nanomicelle.Modeling of H9c2 cardiomyocyte apoptosis induced by 10 mmol·L^-1 isoproterenol was performed.The isodose baicalin and baicalin PEG-PCL nanomicelle were pretreated for 1 h before modeling,and the apoptosis-related caspase 3 activity,ROS levels and expression levels of Bcl-2 and Bax proteins were determined.RESULTS Baicalin PEG-PCL nanomicelle had excellent characteristics such as small particle size and slow release rate.Fluorescence tests showed that PEG-PCL nanomicelle can promote the cell uptake of drugs,and can also accumulate drugs in the mitochondria.The results of death test showed that baicalin PEG-PCL nanomicelle can significantly reduce apoptosis-related caspase 3 activity,ROS levels,reduce the expression of pro-apoptotic Bax,and significantly increase the expression of anti-apoptotic Bcl-2.There was a significant difference compared with the baicalin.CONCLUSION Baicalin PEG-PCL nanomicelle can promote the uptake of baicalin by cardiomyocytes and help to accumulate drugs in the mitochondria,thus greatly improving the anti-cardiomyocyte apoptosis effect.