青龙衣中胡桃醌对S180肉瘤小鼠的抑瘤作用研究

Studies on Inhibition of Juglone in Exocarpium Juglandis Immaturum on S_(180) Sarcoma in Mice

目的研究胡桃醌的体内抗肿瘤作用,探讨其可能的作用机制。方法建立S180荷瘤小鼠肉瘤模型,考察胡桃醌的体内抑瘤活性及其对胸腺和脾脏指数的影响;HE染色,光镜观察各组小鼠肿瘤组织生长及病理变化;透射电镜观察肿瘤细胞超微结构改变;流式细胞仪检测肿瘤组织细胞的凋亡率及细胞周期的改变。结果在2,4和8μmol·kg-1·d-1剂量下,胡桃醌对S180实体瘤的抑瘤率分别为29.04%,37.33%,52.66%,瘤重与空白对照组比较均显著降低(P<0.01);胡桃醌4,8μmol·kg-1·d-1剂量组脾脏指数降低(P<0.01),各剂量组胸腺指数无明显变化(P>0.05);光镜下胡桃醌各组肿瘤组织坏死程度明显增加;电镜下观察发现,胡桃醌各组均出现核染色质凝集、边聚,凋亡小体形成等典型的细胞凋亡形态学改变;胡桃醌2,4和8μmol·kg-1·d-1剂量下,流式细胞仪检测发现凋亡峰,凋亡率分别为(5.58±0.63)%、(6.66±0.85)%和(10.27±1.05)%。细胞周期观察发现,G1期细胞百分率有所降低,而G2/M期有所增加,推测胡桃醌可将细胞阻滞于G2/M期,但还需进一步研究证实。结论胡桃醌能有效抑制小鼠S180实体肿瘤的生长,诱导肿瘤细胞凋亡及引起G2/M期阻滞可能是其主要作用途径。

OBJECTIVE To study the anti-tumor effects ofjuglone on sarcoma grafts of S180mice in vivo. METHODS The graft mouse tumor model S180 was used to investigate the effects ofjuglone from Exocarpium Juglandis Immaturum on tumor growth and the weights of immune organs. After HE staining, the growth and patho-morphologic changes of tumor cells were observed by optical microscope. The ultrastructural changes of tumor cells were observed by electron microscopy. Flow cytometry was used to observe the rate ofapoptosis and cell cycle arrest in S180 cells. RESULTS The inhibitory rate ofjuglone at the dosage of 2, 4 and 8 μmol·kg^-1·d^-1 was 29.04%, 37.33%, 52.66% respectively. Spleen index in 4, 8 μmol·kg^-1·d^-1 dosage group showed significant decrease （P〈0.01）, and ehymus index had no change. Under the optical microscope, the degree of cell necrosis ofjuglone group increased significantly compared with the control group. The typical morphological changes of apoptosis were observed, such as chromatin condensation, margination against nuclear envelope and formation of apoptotic bodies by transmission electron microscopy. The subdiploid peak was found and the apoptosis rate of juglone at the dosage of 2, 4 and 8 μmol·kg^-1·d^-1 was （5.58±0.63）%, （6.66±0.85）%, （10.27±1.05）% respectively. The percentage of cells in G1 phase of the cell cycle was decreased, whereas the amount of cells in the G2/M phase was increased. CONCLUSION Juglone inhibited the growth of sarcoma grafts of S180 mice effectively. Induction of cells apoptosis and G2/M phase cycle arrest may play an important role in the antitumor effect ofjuglone.