Background: Light management plays an important role in the growth and behavior of broiler chickens. Constant light in early post hatch stage has been a common practice in broiler industry for improving growth perform...Background: Light management plays an important role in the growth and behavior of broiler chickens. Constant light in early post hatch stage has been a common practice in broiler industry for improving growth performance,while whether and how constant light in early life affects the behavior of broiler chickens is rarely reported.Results: In this study, newly hatched chicks were kept in either constant(24 L:0 D, LL) or(12 L:12 D, LD) photoperiod for 7 d and then maintained in 12 L:12 D thereafter until 21 days of age. Constant light increased the average daily feed intake but not the body weight, which led to higher feed conversion ratio. Chickens in LL group exhibited fear-related behaviors, which was associated with higher corticosterone, lower melatonin and 5-HT levels. Concurrently, constant light exposure increased the mRNA expression of clock-related genes and suppressed the expression of antioxidative genes in the hippocampus. Moreover, brain derived neurotrophic factor/extracel ular signal-regulated kinase(BDNF/ERK) pathway was suppressed in the hippocampus of chickens exposed to constant light in the first week post hatching.Conclusions: These findings indicate that constant light exposure in early life suppress melatonin secretion and disrupts hippocampal expression of genes involved in circadian clock and BDNF/ERK pathway, thereby contributing to fear-related behaviors in the chicken.展开更多
Studies have shown that the natural flavonoid luteolin has neurotrophic activity. In this study, we investigated the effect of luteolin in a mouse model of Down syndrome. Ts65 Dn mice, which are frequently used as a m...Studies have shown that the natural flavonoid luteolin has neurotrophic activity. In this study, we investigated the effect of luteolin in a mouse model of Down syndrome. Ts65 Dn mice, which are frequently used as a model of Down syndrome, were intraperitoneally injected with 10 mg/kg luteolin for 4 consecutive weeks starting at 12 weeks of age. The Morris water maze test was used to evaluate learning and memory abilities, and the novel object recognition test was used to assess recognition memory. Immunohistochemistry was performed for the neural stem cell marker nestin, the astrocyte marker glial fibrillary acidic protein, the immature neuron marker DCX, the mature neuron marker NeuN, and the cell proliferation marker Ki67 in the hippocampal dentate gyrus. Nissl staining was used to observe changes in morphology and to quantify cells in the dentate gyrus. Western blot assay was used to analyze the protein levels of brain-derived neurotrophic factor(BDNF) and phospho-extracellular signal-regulated kinase 1/2(p-ERK1/2) in the hippocampus. Luteolin improved learning and memory abilities as well as novel object recognition ability, and enhanced the proliferation of neurons in the hippocampal dentate gyrus. Furthermore, luteolin increased expression of nestin and glial fibrillary acidic protein, increased the number of DCX^+ neurons in the granular layer and NeuN^+ neurons in the subgranular region of the dentate gyrus, and increased the protein levels of BDNF and p-ERK1/2 in the hippocampus. Our findings show that luteolin improves behavioral performance and promotes hippocampal neurogenesis in Ts65 Dn mice. Moreover, these effects might be associated with the activation of the BDNF/ERK1/2 pathway.展开更多
基金supported by the National Natural Science Foundation of China (31972638)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)+1 种基金the Postgraduate Research&Practice Innovation Program of Jiangsu Province (KYCX18_0716)Jiangsu Collaborative Innovation Center of Meat Production and Processing,Quality,Safety Control
文摘Background: Light management plays an important role in the growth and behavior of broiler chickens. Constant light in early post hatch stage has been a common practice in broiler industry for improving growth performance,while whether and how constant light in early life affects the behavior of broiler chickens is rarely reported.Results: In this study, newly hatched chicks were kept in either constant(24 L:0 D, LL) or(12 L:12 D, LD) photoperiod for 7 d and then maintained in 12 L:12 D thereafter until 21 days of age. Constant light increased the average daily feed intake but not the body weight, which led to higher feed conversion ratio. Chickens in LL group exhibited fear-related behaviors, which was associated with higher corticosterone, lower melatonin and 5-HT levels. Concurrently, constant light exposure increased the mRNA expression of clock-related genes and suppressed the expression of antioxidative genes in the hippocampus. Moreover, brain derived neurotrophic factor/extracel ular signal-regulated kinase(BDNF/ERK) pathway was suppressed in the hippocampus of chickens exposed to constant light in the first week post hatching.Conclusions: These findings indicate that constant light exposure in early life suppress melatonin secretion and disrupts hippocampal expression of genes involved in circadian clock and BDNF/ERK pathway, thereby contributing to fear-related behaviors in the chicken.
文摘目的:研究淫羊藿苷(ICA)对精神分裂症模型大鼠认知功能的改善作用及机制。方法:将SD大鼠分为空白对照组、模型组和ICA低、中、高剂量组(15、30、60 mg/kg),除空白对照组外,其余组大鼠均腹腔注射N-甲基-D-天冬氨酸受体拮抗剂MK-801(0.2 mg/kg)复制精神分裂症模型,每天1次,连续14天。造模成功后,ICA各剂量组大鼠灌胃相应药物,空白对照组和模型组灌胃等体积水,每天1次,连续28天。采用Morris水迷宫实验、旷场实验、强迫游泳实验和Y迷宫实验观察大鼠行为学变化;采用Nissl法染色观察大鼠海马组织病理变化;采用酶联免疫吸附法(ELISA)检测大鼠脑组织中胆碱能相关指标[乙酰胆碱(Ach)、胆碱乙酰转移酶(ChAT)、乙酰胆碱酯酶(AchE)]的水平;采用实时荧光定量聚合酶链式反应(PCR)法检测大鼠脑组织中脑源性神经营养因子(BDNF)、细胞外信号调节蛋白激酶(ERK)、环磷腺苷反应元件结合蛋白(CREB)的mRNA的表达水平;采用Western blot法检测大鼠脑组织中BDNF、ERK、CREB蛋白和凋亡相关蛋白[B淋巴细胞瘤2(Bcl-2)及其相关X蛋白(Bax)、胱天蛋白酶3(Caspase-3)]的表达或磷酸化水平。结果:与空白组比较,模型组大鼠逃避潜伏期、T1~T3时段活动路程长度、累积不动时间和脑组织中Caspase-3蛋白的表达水平均显著增加或升高(P<0.05);穿台次数、交替率、海马组织中Nissl染色阳性神经元数以及脑组织中Ach和ChAT水平、Bcl-2/Bax比值、BDNF m RNA和蛋白的表达水平、ERK和CREB mRNA的表达水平、ERK1/2和CREB磷酸化水平均显著减少或降低(P<0.05)。与模型组比较,ICA高剂量组大鼠逃避潜伏期、T1~T3段活动路程长度、累积不动时间、Nissl染色阳性神经元数、脑组织中AchE水平和Caspase-3蛋白的相对表达量均显著减少或降低(P<0.05);穿台次数、交替率,脑组织中Ach和ChAT水平、Bcl-2/Bax比值、BDNF m RNA和蛋白的表达水平、ERK和CREB mRNA的表达水平、ERK1/2和CREB的磷酸化水平均显著增加或升高(P<0.05)。ICA低、中剂量组大鼠上述部分指标较模型组显著改善(P<0.05)。结论:ICA可改善精神分裂症模型大鼠的认知功能,其作用机制可能与调节胆碱能系统、抑制神经元凋亡、促进BDNF/ERK/CREB信号通路的表达有关。
基金supported by the Project Funding for the Training of High Level Health Professionals in Changzhou of China,No.2016CZLJ013(to BY)Science and Technology Support Project of Changzhou of China,No.Social Development CE20175021(to BY)Application Basic Research Project of Changzhou of China,No.CJ20160036(to WBZ)
文摘Studies have shown that the natural flavonoid luteolin has neurotrophic activity. In this study, we investigated the effect of luteolin in a mouse model of Down syndrome. Ts65 Dn mice, which are frequently used as a model of Down syndrome, were intraperitoneally injected with 10 mg/kg luteolin for 4 consecutive weeks starting at 12 weeks of age. The Morris water maze test was used to evaluate learning and memory abilities, and the novel object recognition test was used to assess recognition memory. Immunohistochemistry was performed for the neural stem cell marker nestin, the astrocyte marker glial fibrillary acidic protein, the immature neuron marker DCX, the mature neuron marker NeuN, and the cell proliferation marker Ki67 in the hippocampal dentate gyrus. Nissl staining was used to observe changes in morphology and to quantify cells in the dentate gyrus. Western blot assay was used to analyze the protein levels of brain-derived neurotrophic factor(BDNF) and phospho-extracellular signal-regulated kinase 1/2(p-ERK1/2) in the hippocampus. Luteolin improved learning and memory abilities as well as novel object recognition ability, and enhanced the proliferation of neurons in the hippocampal dentate gyrus. Furthermore, luteolin increased expression of nestin and glial fibrillary acidic protein, increased the number of DCX^+ neurons in the granular layer and NeuN^+ neurons in the subgranular region of the dentate gyrus, and increased the protein levels of BDNF and p-ERK1/2 in the hippocampus. Our findings show that luteolin improves behavioral performance and promotes hippocampal neurogenesis in Ts65 Dn mice. Moreover, these effects might be associated with the activation of the BDNF/ERK1/2 pathway.
