Mounting evidence indicates that amyloid β protein（Aβ） exerts neurotoxicity by disrupting the blood-brain barrier（BBB） in Alzheimer＇s disease. Hyperoside has neuroprotective effects both in vitro and in vivo ag...Mounting evidence indicates that amyloid β protein（Aβ） exerts neurotoxicity by disrupting the blood-brain barrier（BBB） in Alzheimer＇s disease. Hyperoside has neuroprotective effects both in vitro and in vivo against Aβ. Our previous study found that hyperoside suppressed Aβ1-42-induced leakage of the BBB, however, the mechanism remains unclear. In this study, bEnd.3 cells were pretreated with 50, 200, or 500 μM hyperoside for 2 hours, and then exposed to Aβ1-42 for 24 hours. Cell viability was determined using 3-（4,5-dimethyl-2-thiazolyl）-2,5-diphenyl-2-H-tetrazolium bromide assay. Flow cytometry and terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling assay were used to analyze cell apoptosis. Western blot assay was carried out to analyze expression levels of Bax, Bcl-2, cytochrome c, caspase-3, caspse-8, caspase-9, caspase-12, occludin, claudin-5, zonula occludens-1, matrix metalloproteinase-2（MMP-2）, and MMP-9. Exposure to Aβ1-42 alone remarkably induced bEnd.3 cell apoptosis; increased ratios of cleaved caspase-9/caspase-9, Bax/Bcl-2, cleav ed caspase-8/caspase-8, and cleaved caspase-12/caspase-12; increased expression of cytochrome c and activity of caspase-3; diminished levels of zonula occludens-1, claudin-5, and occludin; and increased levels of MMP-2 and MMP-9. However, hyperoside pretreatment reversed these changes in a dose-dependent manner. Our findings confirm that hyperoside alleviates fibrillar Aβ1-42-induced BBB disruption, thus offering a feasible therapeutic application in Alzheimer＇s disease.展开更多
Crocetin is an aglycon of carotenoid extracted by saffron stigmas (Crocus sativus L.) and known to have a potent anti-oxidative effect. Amyliod β (Aβ), hallmark of Alzheimer’s disease, is reported to have neurotoxi...Crocetin is an aglycon of carotenoid extracted by saffron stigmas (Crocus sativus L.) and known to have a potent anti-oxidative effect. Amyliod β (Aβ), hallmark of Alzheimer’s disease, is reported to have neurotoxicity partly via oxidative stress. In this study, we investigated the effect of crocetin on hippocampal HT22 cell death induced by Aβ1-42. Furthermore, to clarify the mechanism underlying the protective effects of crocetin against Aβ1-42- induced cell death, we measured reactive oxygen species (ROS) production by CM-H2DCFDA kit assay. Crocetin at 1 -10 μM protected HT22 cells against Aβ1-42-induced neuronal cell death and decreased ROS production increased by Aβ1-42. These results that crocetin has the potent neuroprotective effect against Aβ1-42-induced cytotoxicity in hippocampal cells by attenuating oxidative stress, suggest that crocetin may provide a useful therapeutic strategy against Aβ-related disorders.展开更多
目的探讨G蛋白耦联受体30(G protein coupled receptor 30,GPR30)激动剂对β淀粉样蛋白(amyloidβ-protein,Aβ)_(1-42)所致小鼠认知功能障碍的治疗作用。方法将72只ICR小鼠随机分为对照组、模型组、阳性对照组、G1低剂量组、G1中剂量组...目的探讨G蛋白耦联受体30(G protein coupled receptor 30,GPR30)激动剂对β淀粉样蛋白(amyloidβ-protein,Aβ)_(1-42)所致小鼠认知功能障碍的治疗作用。方法将72只ICR小鼠随机分为对照组、模型组、阳性对照组、G1低剂量组、G1中剂量组和G1高剂量组。采用双侧海马脑立体定位注射Aβ_(1-42)建立阿尔茨海默病认知功能障碍模型,48h后给予GPR30激动剂G1(1mg/kg、2mg/kg、4mg/kg)。进行Morris水迷宫实验、避暗实验和新物体识别实验测试小鼠的认知能力,采用蛋白质印迹法检测小鼠海马组织中Bcl-2、Bax、caspase-3、脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)、cAMP效应元件结合蛋白(cAMP response element binding protein,CREB)、p-CREB的表达水平。结果Morris水迷宫实验中,G1高剂量组小鼠的目标象限停留时间百分比和穿越平台次数显著高于模型组(P<0.05);避暗实验中,G1中、高剂量组小鼠的错误次数均显著少于模型组(P<0.05),避暗潜伏期均显著长于模型组(P<0.05);新物体识别实验中,G1中、高剂量组小鼠的识别指数均显著高于模型组(P<0.05)。G1高剂量组小鼠海马组织中的p-CREB/CREB、mBDNF/proBDNF、Bcl-2/Bax的比例显著高于模型组(P<0.05),活化的caspase-3/pro-caspase-3的比例显著低于模型组(P<0.05)。结论GPR30激动剂可通过激活CREB/BDNF通路对Aβ_(1-42)诱导的小鼠认知障碍和神经元凋亡产生保护作用。展开更多
基金financially supported by the National Natural Science Foundation of China,No.81573771the Natural Science Foundation of Jiangsu Province of China,No.BK20151599
文摘Mounting evidence indicates that amyloid β protein（Aβ） exerts neurotoxicity by disrupting the blood-brain barrier（BBB） in Alzheimer＇s disease. Hyperoside has neuroprotective effects both in vitro and in vivo against Aβ. Our previous study found that hyperoside suppressed Aβ1-42-induced leakage of the BBB, however, the mechanism remains unclear. In this study, bEnd.3 cells were pretreated with 50, 200, or 500 μM hyperoside for 2 hours, and then exposed to Aβ1-42 for 24 hours. Cell viability was determined using 3-（4,5-dimethyl-2-thiazolyl）-2,5-diphenyl-2-H-tetrazolium bromide assay. Flow cytometry and terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling assay were used to analyze cell apoptosis. Western blot assay was carried out to analyze expression levels of Bax, Bcl-2, cytochrome c, caspase-3, caspse-8, caspase-9, caspase-12, occludin, claudin-5, zonula occludens-1, matrix metalloproteinase-2（MMP-2）, and MMP-9. Exposure to Aβ1-42 alone remarkably induced bEnd.3 cell apoptosis; increased ratios of cleaved caspase-9/caspase-9, Bax/Bcl-2, cleav ed caspase-8/caspase-8, and cleaved caspase-12/caspase-12; increased expression of cytochrome c and activity of caspase-3; diminished levels of zonula occludens-1, claudin-5, and occludin; and increased levels of MMP-2 and MMP-9. However, hyperoside pretreatment reversed these changes in a dose-dependent manner. Our findings confirm that hyperoside alleviates fibrillar Aβ1-42-induced BBB disruption, thus offering a feasible therapeutic application in Alzheimer＇s disease.
文摘Crocetin is an aglycon of carotenoid extracted by saffron stigmas (Crocus sativus L.) and known to have a potent anti-oxidative effect. Amyliod β (Aβ), hallmark of Alzheimer’s disease, is reported to have neurotoxicity partly via oxidative stress. In this study, we investigated the effect of crocetin on hippocampal HT22 cell death induced by Aβ1-42. Furthermore, to clarify the mechanism underlying the protective effects of crocetin against Aβ1-42- induced cell death, we measured reactive oxygen species (ROS) production by CM-H2DCFDA kit assay. Crocetin at 1 -10 μM protected HT22 cells against Aβ1-42-induced neuronal cell death and decreased ROS production increased by Aβ1-42. These results that crocetin has the potent neuroprotective effect against Aβ1-42-induced cytotoxicity in hippocampal cells by attenuating oxidative stress, suggest that crocetin may provide a useful therapeutic strategy against Aβ-related disorders.
