多不饱和脂肪酸对Δ15 Des转基因小鼠前列腺素E_(2)水平的影响

Effects of polyunsaturated fatty acids on prostaglandin E_(2)content in transgenicΔ15 Des mice

目的探讨多不饱和脂肪酸(PUFAs)对Δ15脂肪酸去饱和酶(Δ15 Des)转基因小鼠前列腺素E_(2)(PGE_(2))水平的影响。方法取C57BL/6野生型(WT)雄性小鼠和Δ15 Des转基因雄性小鼠作为对照组(n=5,WT组)和实验组(n=5,TG组),6%花生四烯酸(ARA)饲养8周,每周记录小鼠体质量变化;8周后麻醉处死2组小鼠,冰上分离小鼠肝脏、睾丸及肌肉组织,采用气相色谱(GC)检测2组小鼠各组织中脂肪酸(FAs)的组成及水平,采用酶联免疫吸附(ELISA)和实时荧光定量PCR(RT-qPCR)测定2组小鼠各组织中PGE_(2)的水平及前列腺素E合酶1(PTGES1)、前列腺素E合酶2(PTGES2)信使RNA(mRNA)的相对表达。结果第1~8周,2组小鼠体质量均在增长,2组间比较、差异无统计学意义(P>0.05);WT组小鼠各组织中PUFAs主要是欧米伽-6 PUFAs(n-6 PUFAs);与WT组相比,TG组小鼠各组织中ARA水平降低、二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)水平升高(P<0.05或P<0.01),睾丸组织中亚油酸(LA)水平升高、二十二碳四烯酸(DTA)水平降低(P<0.05);TG组小鼠睾丸、肌肉组织中PGE_(2)水平低于WT组(P<0.05或P<0.01);TG组小鼠肝脏、睾丸组织中PTGES1、PTGES2 mRNA表达低于WT组(P<0.05或P<0.01)。结论PUFAs可减少Δ15 Des转基因小鼠ARA的合成,降低与PGE_(2)相关的合成酶表达,从而调节体内PGE_(2)的水平。

Objective To investigate the effect of polyunsaturated fatty acids(PUFAs)on prostaglandin E_(2)(PGE_(2))content in transgenic mice withΔ15 fatty acid desaturase(Δ15 Des).Methods C57BL/6 wild-type(WT)male mice andΔ15 Des transgenic male mice were chosen as control group(n=5,WT group)and experimental group(n=5,TG group);6%arachidonic acid(ARA)was fed to subjects for 8 weeks,and the body weight changes of mice were recorded every week.Eight weeks later,two groups of mice were put to death under anesthesia,and their liver,testis,and muscle tissues were separated on ice.The composition and level of fatty acids(FAs)in each tissue of two groups of mice were detected by gas chromatography(GC);levels of PGE_(2),prostaglandin E synthase 1(PTGES1)and prostaglandin E synthase 2(PTGES2)messenger RNA relative expression in each tissue of two groups determined by enzyme-linked immunosorbent assay(ELISA)and quantitative real-time fluorescence PCR(RT-qPCR).Results From week 1 to week 8,the body mass of mice in both groups increased,and there was no significant difference between the two groups(P>0.05).Omega-6 PUFAs(n-6 PUFAs)are the main PUFAs in WT group.Compared with WT group,ARA levels in TG group tissues decreased,levels of eicosapentaenoic acid(EPA)and docosahexaenoic acid(DHA)increased(P<0.05 or P<0.01),levels of linoleic acid(LA)increased and docosatetraenoic acid(DTA)in testis decreased(P<0.05).PGE_(2)levels in testis and muscle tissue in TG group were lower than that of WT group(P<0.05 or P<0.01).The expression of PTGES1 and PTGES2 mRNA in liver and testis of TG group was lower than that of WT group(P<0.05 or P<0.01).Conclusion PUFAs can reduce the synthesis of ARA and the expression of PGE_(2)-related synthetase inΔ15 Des transgenic mice,thus regulating the level of PGE_(2)in vivo.