塞来昔布联合齐留通对ApoE^(-/-)小鼠动脉粥样硬化的影响

Effects of celecoxib combined with zileuton on atherosclerosis in ApoE^(-/-) mice

目的:探讨环加氧酶-2(COX-2)抑制剂塞来昔布联合5-脂加氧酶(5-LO)抑制剂齐留通对ApoE^(-/-)小鼠动脉粥样硬化(AS)病变的影响及机制。方法:雄性ApoE^(-/-)小鼠随机分成AS模型组、塞来昔布组(80 mg/kg/d)及塞来昔布联合齐留通(400 mg/kg/d)组(高脂饲料喂养),野生型雄性C57BL/6J小鼠为正常对照组(普通饲料喂养),每组12只。每日灌胃给药18周后,取血测定血脂水平,小动物B超下测量主动脉弓斑块面积比(%)、主动脉全长油红O染色测量阳性斑块面积比(%)及主动脉根部切片苏木精-伊红(HE)染色测量斑块面积比(%)和内中膜厚度(IMT)并观察AS病理形态学改变,ELISA测定主动脉匀浆花生四烯酸(AA)代谢产物前列腺素E2(PGE2)和白三烯(LTs)[包括白三烯B4(LTB4)和半胱氨酰白三烯(CysLTs)]含量。结果:与正常对照组比较,AS模型组小鼠血清总胆固醇(TC)、低密度脂蛋白(LDL-C)和高密度脂蛋白(HDL-C)水平明显升高(P<0.05或P<0.01),但总甘油三酯(TG)水平无明显改变(P>0.05);塞来昔布组及塞来昔布联合齐留通组血脂各指标与AS模型组比较,差异无统计学意义(P>0.05)。小动物B超、主动脉全长油红O染色及主动脉根部切片HE染色病理学观察及定量检测结果均表明AS模型组小鼠形成了明显的主动脉AS病变,塞来昔布加重AS病变,塞来昔布联合齐留通减轻塞来昔布加重的AS病变(均P<0.05或P<0.01)。AS模型组小鼠主动脉匀浆PGE2、LTB4和CysLTs含量均较正常对照组显著升高(P<0.01);与AS模型组相比,塞来昔布组小鼠主动脉匀浆PGE2含量显著降低,而LTB4和CysLTs含量则显著升高(P<0.01);与塞来昔布组相比,塞来昔布联合齐留通组主动脉匀浆PGE2含量无明显改变(P>0.05),但LTB4和CysLTs含量明显降低(P<0.01)。结论:塞来昔布上调LTs加重ApoE^(-/-)小鼠AS病变的作用可被5-LO抑制剂齐留通逆转。

Objective:To investigate the effect of cyclooxygenase-2(COX-2)inhibitor celecoxib combined with 5-lipoxygenase(5-LO)inhibitor zileuton on atherosclerosis(AS)in ApoE^(-/-) mice and its mechanism.Methods:The male ApoE^(-/-) mice fed high fat diet were randomly divided into AS model group,celecoxib group and celecoxib combined with zileuton group,and the malewild-type C57BL/6J mice fed normal diet were used as the control group(n=12 per group).The mice of celecoxib group and celecoxib combined with zileuton group were orally administrated celecoxib(80mg/kg/d)alone or combined with zileuton(400mg/kg/d)each day for 18 weeks.After that,the serum lipid levelswere measured,furthermore,the aortic arch plaque area ratio(%)under type B ultrasound,the positive plaque area ratio(%)of red O oil stained full-length aorta,the plaque area ratio(%)and intima-media thickness(IMT)value of the HE stained aortic root sections as well asthe aortic pathomorphologic changes were detected.In addition,the levels of arachidonic acid(AA)metabolitesprostaglandin E2(PGE2)and leukotriene(LTs)[including leukotriene B4(LTB4)and CysLTs]in aortic tissue were determined.Results:Compared with the control group,AS significantly increased the serum levels of total cholesterol(TC),low density lipoprotein(LDL-C)and high-density lipoprotein(HDL-C)(P<0.05 or P<0.01)but had no effect on total triglycercide(TG)(P>0.05);compared with theAS model group,celecoxib alone or combined with zileuton did not affect the serum hyperlipid emia(P>0.05).The results of aortic pathomorphologic changes and the AS quantified measured values of type B ultrasound,full-length aortaoil red O staining and aortic root sections HE stainingall showed that the mice in AS model group had significant aortic AS lesions,which were aggravated by celecoxiband alleviated by celecoxib combined with ziliuton(P<0.05 or P<0.01).The aortic contents of PGE2,LTB4 and CysLTs in AS model group were all significantly higher than those in the control group(P<0.01);compared with AS model group,celecoxib significantly decreased the PGE2 level but markedly increased the levels of LTB4 and CysLTs(P<0.01);compared with celecoxib group,celecoxib combined with zileuton did not change the PGE2 level(P>0.05)but depress the levels of LTB4 and CysLTs(P<0.01).Conclusion:Celecoxib aggravates AS by up-regulating LTsin ApoE^(-/-) mice,which can be reversed by 5-LO inhibitor zileuton.