Some citrus flavonoids have been reported to possess antioxidant activities that moderate endothelial dysfunction and show protective effects on cardiovascular disease. We have investigated the protective effects of n...Some citrus flavonoids have been reported to possess antioxidant activities that moderate endothelial dysfunction and show protective effects on cardiovascular disease. We have investigated the protective effects of nobiletin (5,6,7,8,3’,4’-hexamethoxy flavone) derived from the peel of Citrus depressa Hayata (Shiikuwasha), a citrus fruit produced in Okinawa prefecture in Japan on hypertension and thrombogenicity in cerebral vessels of stroke-prone spontaneously hypertensive rats (SHRSP). Nobiletin was added to the diet of male SHRSP (7 weeks old) for 4 weeks. The age-related increase in systolic blood pressure usually observed in SHRSP was significantly suppressed in the treated animals. Thrombogenesis in pial blood vessels, determined using a He-Ne laser technique, and antioxidant activity, assessed by measuring urinary 8-hydroxy-2’-deoxyguanosine (8-OHdG), were significantly reduced after treatment. Urinary nitric oxide (NO) metabolites and acetylcholine-induced endothelial relaxation were increased after dietary intervention. These results strongly suggested that antihypertensive and antithrombotic effects of nobiletin may be related to an increase in bioavailable NO, possibly mediated by the scavenging of reactive oxygen species (ROS).展开更多
Honokiol is a protective agent for cerebral ischemia injury when administered intravenously. In the present study, we aimed to investigate the oral effect of honokiol microemulsion on cerebral isehemia-reperfusion （...Honokiol is a protective agent for cerebral ischemia injury when administered intravenously. In the present study, we aimed to investigate the oral effect of honokiol microemulsion on cerebral isehemia-reperfusion （I-R） injury in rats and stroke in SHRsp. Both tMCAO and SHRsp models in rats were used to evaluate the efficacy of the microemulsion. Rat aortic segment contraction test, primary rat aortic endothelial cells and primary brain microvascular endothelial cells （BMECs） injured by OGD-R were used to explore its potential action mechanism. Oral honokiol microemulsion significantly reduced infarct volume, neurological score and brain water content in tMCAO model, and it evidently reduced neurological score and increased the survival rate of SHRsp. Moreover, honokiol significantly inhibited aortic contraction induced by KC1 and phenylephrine, and L-NAME suppressed these inhibitory effects. On the other side, honokiol increased NO and p-eNOS levels in rat endothelial cells. In addition, it also protects BMECs against OGD-R injury and increased eNOS expression in BMECs. In conclusion, oral honokiol administration has protective effects in tMCAO and in SHRsp rats, and its action mechanism is likely to be associated with its vasodilative effect produced by eNOS activation and with its protective effect on BMECs.展开更多
目的:探讨Tempol对脑小血管病变卒中发生的影响。方法:以卒中易感型自发性高血压大鼠(SHRSP)为脑小血管病动物模型,将其随机分为对照组与Tempol处理组,每组10只。利用行为学观察评估卒中事件的发生率及大鼠的存活率,Elisa法测定额叶皮...目的:探讨Tempol对脑小血管病变卒中发生的影响。方法:以卒中易感型自发性高血压大鼠(SHRSP)为脑小血管病动物模型,将其随机分为对照组与Tempol处理组,每组10只。利用行为学观察评估卒中事件的发生率及大鼠的存活率,Elisa法测定额叶皮层丙二醛(MDA)的含量、总抗氧化能力(TAC)及超氧化物歧化酶(SOD)的活性,Evans blue染色测定血脑屏障的破坏程度,Western Blot测定紧密连接蛋白occludin、claudin-5与Zo-1的表达。结果:与对照组相比,Tempol处理组首次卒中发病时间推迟(36 d vs 20 d,P<0.05),卒中发病率下降(75%vs 100%,P<0.05),存活率提高(45%vs 25%,P<0.05)。Tempol处理组额叶皮层MDA含量(nmol/mg)降低(0.63±0.04 vs1.23±0.07,P<0.05),TAC与SOD酶活性(U/mg)增加(25.6±3.4 vs 15.6±1.2,P<0.05;7.46±0.92 vs 5.2±0.7,P<0.05)。Tempol处理组额叶皮层Evans blue含量(μg/mg)降低(3.75±0.42 vs 6.16±0.34,P<0.05),且伴有occludin、claudin-5与Zo-1蛋白表达增加。结论:Tempol可通过抑制氧化应激,减轻血脑屏障破坏,降低大鼠脑小血管病卒中发生风险。展开更多
文摘Some citrus flavonoids have been reported to possess antioxidant activities that moderate endothelial dysfunction and show protective effects on cardiovascular disease. We have investigated the protective effects of nobiletin (5,6,7,8,3’,4’-hexamethoxy flavone) derived from the peel of Citrus depressa Hayata (Shiikuwasha), a citrus fruit produced in Okinawa prefecture in Japan on hypertension and thrombogenicity in cerebral vessels of stroke-prone spontaneously hypertensive rats (SHRSP). Nobiletin was added to the diet of male SHRSP (7 weeks old) for 4 weeks. The age-related increase in systolic blood pressure usually observed in SHRSP was significantly suppressed in the treated animals. Thrombogenesis in pial blood vessels, determined using a He-Ne laser technique, and antioxidant activity, assessed by measuring urinary 8-hydroxy-2’-deoxyguanosine (8-OHdG), were significantly reduced after treatment. Urinary nitric oxide (NO) metabolites and acetylcholine-induced endothelial relaxation were increased after dietary intervention. These results strongly suggested that antihypertensive and antithrombotic effects of nobiletin may be related to an increase in bioavailable NO, possibly mediated by the scavenging of reactive oxygen species (ROS).
基金National Natural Science Foundation of China(Grant No.81503060)
文摘Honokiol is a protective agent for cerebral ischemia injury when administered intravenously. In the present study, we aimed to investigate the oral effect of honokiol microemulsion on cerebral isehemia-reperfusion （I-R） injury in rats and stroke in SHRsp. Both tMCAO and SHRsp models in rats were used to evaluate the efficacy of the microemulsion. Rat aortic segment contraction test, primary rat aortic endothelial cells and primary brain microvascular endothelial cells （BMECs） injured by OGD-R were used to explore its potential action mechanism. Oral honokiol microemulsion significantly reduced infarct volume, neurological score and brain water content in tMCAO model, and it evidently reduced neurological score and increased the survival rate of SHRsp. Moreover, honokiol significantly inhibited aortic contraction induced by KC1 and phenylephrine, and L-NAME suppressed these inhibitory effects. On the other side, honokiol increased NO and p-eNOS levels in rat endothelial cells. In addition, it also protects BMECs against OGD-R injury and increased eNOS expression in BMECs. In conclusion, oral honokiol administration has protective effects in tMCAO and in SHRsp rats, and its action mechanism is likely to be associated with its vasodilative effect produced by eNOS activation and with its protective effect on BMECs.
文摘目的:探讨Tempol对脑小血管病变卒中发生的影响。方法:以卒中易感型自发性高血压大鼠(SHRSP)为脑小血管病动物模型,将其随机分为对照组与Tempol处理组,每组10只。利用行为学观察评估卒中事件的发生率及大鼠的存活率,Elisa法测定额叶皮层丙二醛(MDA)的含量、总抗氧化能力(TAC)及超氧化物歧化酶(SOD)的活性,Evans blue染色测定血脑屏障的破坏程度,Western Blot测定紧密连接蛋白occludin、claudin-5与Zo-1的表达。结果:与对照组相比,Tempol处理组首次卒中发病时间推迟(36 d vs 20 d,P<0.05),卒中发病率下降(75%vs 100%,P<0.05),存活率提高(45%vs 25%,P<0.05)。Tempol处理组额叶皮层MDA含量(nmol/mg)降低(0.63±0.04 vs1.23±0.07,P<0.05),TAC与SOD酶活性(U/mg)增加(25.6±3.4 vs 15.6±1.2,P<0.05;7.46±0.92 vs 5.2±0.7,P<0.05)。Tempol处理组额叶皮层Evans blue含量(μg/mg)降低(3.75±0.42 vs 6.16±0.34,P<0.05),且伴有occludin、claudin-5与Zo-1蛋白表达增加。结论:Tempol可通过抑制氧化应激,减轻血脑屏障破坏,降低大鼠脑小血管病卒中发生风险。
