刺梨黄酮对阿霉素所致心肌细胞毒性的保护作用

目的 探讨刺梨黄酮（FRRT）对阿霉素（DOX)所致心肌细胞凋亡的影响及机制。 方法 利用1~3 d新生大鼠（每次26只）原代分离培养心肌细胞和H9C2心肌细胞系，5 μmol/L DOX孵育心肌细胞，建立心肌细胞毒性模型，并用FRRT干预，透射电子显微镜观察各组H9C2心肌细胞株超微结构。利用免疫荧光技术和Western blotting检测Bax、P53和Bcl-2蛋白的表达，并对Western blotting检测结果进行半定量分析。 结果 透射电子显微镜观察显示，DOX组细胞内呈现大量的自噬泡和脂褐素, 细胞状态差；FRRT干预后，心肌细胞未见脂褐素的结构，有少量自噬泡。免疫荧光检测显示，DOX组Bax和P53呈阳性表达，Bcl-2呈弱阳性表达；FRRT+DOX组Bax和P53表达不明显，Bcl-2呈强阳性表达。Western blotting检测结果显示，5 μmol/L DOX孵育心肌细胞18 h时，Bax蛋白表达水平达到最高，组间比较，差异有统计学意义（P<0.01）。Bax蛋白在DOX组表达增加，FRRT+DOX组表达减少，组间比较，差异具有统计学意义（P<0.05）；P53蛋白在DOX组表达增加，FRRT+DOX组表达减少，组间比较，差异无统计学意义（P>0.05）；Bcl-2蛋白在DOX组表达减少，FRRT+DOX组表达增加，组间比较，差异具有统计学意义（P<0.05，P<0.01）。 结论 FRRT通过下调DOX引起的心肌细胞凋亡作用，进而发挥对心肌细胞的保护作用。

Protective effect of flavonoids of rosa roxburghii tratt on myocardial cytotoxicity induced by doxorubicin

Objective To investigate the effect and mechanism of flavonoids of rosa roxburghii tratt(FRRT) on apoptosis in doxorubicin(DOX)-induced cardiotoxicity. Methods Myocardial cells were isolated and cultured from 26 newborn rats of 1-3 days or H9C2 myocardial cell line. The myocardial cytotoxicity model was established by incubating myocardial cells with a concentration of 5 μmol/L DOX, and FRRT group were intervened with FRRT incubation in advance. Ultrastructure of H9C2 myocardial cells were observed with transmission electron microscope. The expressions of Bax, P53 and Bcl-2 in myocardial cells were detected with Western blotting and immunofluorescence, and the results of Western blotting were analyzed with semi-quantitatively. Results Transmission electron microscopy showed that myocardial cells had a large number of autophagic vacuoles and lipofuscin, and cells were in poor condition in DOX group, the myocardial cells of the FRRT+DOX group had no structure of lipofuscin, and only a small amount of autophagic vacuoles. The results of immunofluorescence showed that the expressions of Bax and P53 were positive, and Bcl-2 was weakly positive in DOX group. The expression of Bax and P53 were not obvious, and Bcl-2 was strongly positive in FRRT+DOX group. The results of Western blotting showed that the myocardial cells were incubated with DOX for 18hours, the expression level of Bax was the highest, and the difference had statistical significance between groups (P<0.01).The expressions of Bax were increased in DOX group,and reduced in FRRT+DOX group, and the difference had statistical significance between groups (P<0.05). The expressions of P53 were increased in DOX group,and reduced in FRRT group, and the difference without statistial significance between groups(P>0.05). The expressions of Bcl-2 were reduced in DOX group, and increased in FRRT+DOX group, the difference had statistical significance between groups(P<0.05, P<0.01). Conclusion FRRT protects cardiomyocytes by down-regulating DOX-induced cardiomyocyte apoptosis.