During the development of diet-induced obesity,the change of energy matebolism is closely related to the function of the circadian clock in mammals.Luteolin(LU),one of the most common natural flavonoids riched in many...During the development of diet-induced obesity,the change of energy matebolism is closely related to the function of the circadian clock in mammals.Luteolin(LU),one of the most common natural flavonoids riched in many edible plants,can ameliorate obesity by activating adipose tissue browning,but its effect on circadian clock in this process remains poorly understood.Here we found that dietary LU improved circadian misalignment of energy expenditure in high-fat diet(HFD)-fed wild-type(WT)mice.Moreover,dietary LU efficiently elevated uncoupling protein 1 levels in adipose tissue during the dark period,which was similar to the LU-increased hepatic PER2 expressions.Hepatic peroxisome proliferators-activated receptorsα(PPARα)/recombinant retinoid X receptorα(RXRα)/fibroblast growth factor 21(FGF21)pathway was rhythmically elevated by dietary LU in HFD-fed WT mice,whereas the promotion was inhibited in Per2^(-/-)mice.Meanwhile,Per2 deletion abolished the effects of dietary LU on adipose tissue browning in HFD-fed mice.Further,LU treatment directly activated PPARα/RXRα/FGF21 signaling in primary cultured hepatocytes from WT mice rather than Per2^(-/-)mice.Taken together,the deletion of the core clock component Per2 impedes LUinduced adipose tissue browning through weakening PPARα/RXRα/FGF21 pathway in mice,providing a new insight into the interplay of energy metabolism and circadian clock for the anti-obesity activity of LU.展开更多
目的探讨钟基因Per2和钟控基因血管内皮生长因子(VEGF)、Ki67、c-Myc和P53在颊黏膜癌变不同阶段的昼夜节律变化规律以及与癌变发生发展的关系。方法 90只叙利亚金黄地鼠置于12 h光照和12 h黑暗交替环境中饲养,用二甲基苯并蒽(DMBA)涂抹...目的探讨钟基因Per2和钟控基因血管内皮生长因子(VEGF)、Ki67、c-Myc和P53在颊黏膜癌变不同阶段的昼夜节律变化规律以及与癌变发生发展的关系。方法 90只叙利亚金黄地鼠置于12 h光照和12 h黑暗交替环境中饲养,用二甲基苯并蒽(DMBA)涂抹颊黏膜建立金黄地鼠颊癌模型,分别在DMBA涂抹前,涂抹6周和14周后的24 h内的6个不同时间点处死动物,获取正常颊黏膜、癌前病变和癌症3个不同阶段昼夜6个不同时间的组织。经病理学检查确认后,采用实时荧光定量聚合酶链反应检测各时间点Per2、VEGF、Ki67、c-Myc和P53 m RNA的相对表达量,并行余弦分析,以中值、振幅和峰值位相时为指标反映各基因表达的昼夜节律特征。结果 Per2、VEGF、P53和c-Myc m RNA在癌变3个阶段的表达均具有昼夜节律性(P<0.05),而Ki67 m RNA仅在正常黏膜和癌前病变阶段的表达具有昼夜节律性(P<0.05)。Per2和P53 m RNA表达的中值随着癌症的发展而降低(P<0.05),VEGF、c-Myc和Ki67 m RNA表达的中值随着癌症的发展而上升(P<0.05);P53 m RNA的振幅随着癌症的发展而降低(P<0.05),Per2、VEGF、Ki67和c-Myc m RNA的振幅在癌前病变和癌症阶段均高于正常组(P<0.05);在癌前病变阶段,Per2、VEGF和c-Myc m RNA的峰值位相时较正常组提前,而Ki67和P53 m RNA的峰值位相时较正常组滞后。结论随着癌症的发生和发展,钟基因Per2和肿瘤相关钟控基因VEGF、Ki67、c-Myc、P53表达的昼夜节律特征发生明显改变。展开更多
文摘During the development of diet-induced obesity,the change of energy matebolism is closely related to the function of the circadian clock in mammals.Luteolin(LU),one of the most common natural flavonoids riched in many edible plants,can ameliorate obesity by activating adipose tissue browning,but its effect on circadian clock in this process remains poorly understood.Here we found that dietary LU improved circadian misalignment of energy expenditure in high-fat diet(HFD)-fed wild-type(WT)mice.Moreover,dietary LU efficiently elevated uncoupling protein 1 levels in adipose tissue during the dark period,which was similar to the LU-increased hepatic PER2 expressions.Hepatic peroxisome proliferators-activated receptorsα(PPARα)/recombinant retinoid X receptorα(RXRα)/fibroblast growth factor 21(FGF21)pathway was rhythmically elevated by dietary LU in HFD-fed WT mice,whereas the promotion was inhibited in Per2^(-/-)mice.Meanwhile,Per2 deletion abolished the effects of dietary LU on adipose tissue browning in HFD-fed mice.Further,LU treatment directly activated PPARα/RXRα/FGF21 signaling in primary cultured hepatocytes from WT mice rather than Per2^(-/-)mice.Taken together,the deletion of the core clock component Per2 impedes LUinduced adipose tissue browning through weakening PPARα/RXRα/FGF21 pathway in mice,providing a new insight into the interplay of energy metabolism and circadian clock for the anti-obesity activity of LU.
文摘目的探讨钟基因Per2和钟控基因血管内皮生长因子(VEGF)、Ki67、c-Myc和P53在颊黏膜癌变不同阶段的昼夜节律变化规律以及与癌变发生发展的关系。方法 90只叙利亚金黄地鼠置于12 h光照和12 h黑暗交替环境中饲养,用二甲基苯并蒽(DMBA)涂抹颊黏膜建立金黄地鼠颊癌模型,分别在DMBA涂抹前,涂抹6周和14周后的24 h内的6个不同时间点处死动物,获取正常颊黏膜、癌前病变和癌症3个不同阶段昼夜6个不同时间的组织。经病理学检查确认后,采用实时荧光定量聚合酶链反应检测各时间点Per2、VEGF、Ki67、c-Myc和P53 m RNA的相对表达量,并行余弦分析,以中值、振幅和峰值位相时为指标反映各基因表达的昼夜节律特征。结果 Per2、VEGF、P53和c-Myc m RNA在癌变3个阶段的表达均具有昼夜节律性(P<0.05),而Ki67 m RNA仅在正常黏膜和癌前病变阶段的表达具有昼夜节律性(P<0.05)。Per2和P53 m RNA表达的中值随着癌症的发展而降低(P<0.05),VEGF、c-Myc和Ki67 m RNA表达的中值随着癌症的发展而上升(P<0.05);P53 m RNA的振幅随着癌症的发展而降低(P<0.05),Per2、VEGF、Ki67和c-Myc m RNA的振幅在癌前病变和癌症阶段均高于正常组(P<0.05);在癌前病变阶段,Per2、VEGF和c-Myc m RNA的峰值位相时较正常组提前,而Ki67和P53 m RNA的峰值位相时较正常组滞后。结论随着癌症的发生和发展,钟基因Per2和肿瘤相关钟控基因VEGF、Ki67、c-Myc、P53表达的昼夜节律特征发生明显改变。