内源性ω-3多不饱和脂肪酸对顺铂诱导的骨髓抑制的保护作用

Protective Effect of Endogenous ω-3 Polyunsaturated Fatty Acid Against Cisplatin-Induced Myelosuppression

目的:利用mfat-1转基因小鼠,探讨内源性ω-3多不饱和脂肪酸(PUFA)对顺铂诱导的骨髓抑制的保护作用及减少骨髓有核细胞凋亡的作用机制。方法:将实验动物分为4组,分别为野生型小鼠正常对照组、mfat-1转基因小鼠正常对照组、野生型小鼠模型组、mfat-1转基因小鼠模型组。模型组小鼠在d 0和d 7腹腔注射顺铂7.5 mg/kg构建骨髓抑制模型,正常对照组小鼠腹腔注射等量生理盐水,每天观察小鼠状态并测量体重,14 d后取外周血进行血常规分析利用气相色谱检测外周血中PUFA的含量和比例;对各组小鼠股骨中骨髓有核细胞进行计数;通过组织病理学染色观察骨髓组织病理学变化;利用流式细胞术和荧光定量PCR技术检测各组小鼠骨髓组织中有核细胞凋亡情况和凋亡相关基因表达水平的变化。结果:与野生型小鼠相比,mfat-1转基因小鼠外周血中ω-3 PUFA含量显著增加且对顺铂具有更强的耐受性;外周血象分析结果显示,内源性ω-3 PUFA可促进骨髓抑制小鼠外周血中白细胞、红细胞、血小板和血红蛋白的恢复;HE染色结果显示,内源性ω-3 PUFA显著改善顺铂诱导的骨髓组织结构损伤;流式细胞术和PCR结果显示,与野生型模型组小鼠相比,mfat-1转基因模型组小鼠骨髓有核细胞凋亡率显著降低(P<0.001),且抗凋亡基因Bcl-2 mRNA的表达显著增加(P<0.01),而促凋亡基因Bax和Bak mRNA的表达显著降低(P<0.001,P<0.05)。结论:内源性ω-3 PUFA可通过调控凋亡相关基因的表达,减少顺铂引起的骨髓有核细胞凋亡,增加外周血细胞的数量,发挥对顺铂诱导的骨髓抑制的保护作用。

Objective:To investigate the protective effect of endogenousω-3 polyunsaturated fatty acid(PUFA)against cisplatin-induced myelosuppression and the mechanism of reducing apoptosis in bone marrow nucleated cells using mfat-1 transgenic mice.Methods:The experimental animals were divided into 4 groups:wild-type mice normal control group,mfat-1 transgenic mice normal control group,wild-type mice model group and mfat-1 transgenic mice model group.The mice in the model group were injected intraperitoneally with 7.5 mg/kg cisplatin on day 0 and day 7 to construct a myelosuppression model,while the mice in the normal control group were injected intraperitoneally with an equal amount of saline,and their status was observed and their body weight was measured daily.Peripheral blood was taken after 14 day for routine blood analysis,and the content and proportion of PUFA in peripheral blood were detected using gas chromatography.Bone marrow nucleated cells in the femur of mice were counted.The histopathological changes in bone marrow were observed by histopathological staining.The apoptosis of nucleated cells and the expression level changes of apoptosis-related genes in the bone marrow of mice were detected by flow cytometry and fluorescence quantitative PCR.Results:Compared with wild-type mice,mfat-1 transgenic mice showed significantly increased levels of o-3 PUFA in peripheral blood and greater tolerance to cisplatin.Peripheral blood analysis showed that endogenousω-3 PUFA promoted the recovery of leukocytes,erythrocytes,platelets and haemoglobin in peripheral blood of myelosuppressed mice.The results of HE staining showed that endogenous ω-3 PUFA significantly im proved the structural damage of bone marrow tissue induced by cisplatin.Flow cytometry and PCR showed that,compared with wild-type mice model group,the apoptosis rate of bone marrow nucleated cells in mfat-1 transgenic mice was significantly reduced(P<0.001),and the expression of anti-apoptotic genes Bcl-2 mRNA was significantly increased(P<0.01),while the expressions of pro-apoptotic genes Bax and Bak mRNA were significantly reduced(P<0.001,P<0.05).Conclusion:Endogenousω-3 PUFA can reduce cisplatin-induced apoptosis in bone marrow nucleated cells,increase the number of peripheral blood cells and exert a protective effect against cisplatin-induced myelosuppression by regulating the expression of apoptosis-related genes.