Effects of Post-Training Blockade of GABA_BReceptor on Memory of Food Location and Expression of Synapsin I in the Hippocampus of Pigeons (<i>Columba livia</i>)

This study investigated effects of post-training treatment with phaclofen, GABAB receptor antagonist, on the memory of food location and on the expression of Synapsin I in the hippocampus of pigeons. Pigeons were trained in food location (7 sessions) and underwent post-training treatment with phaclofen (0.3 mg/kg, i.p.;PHAC), saline (SAL) or non-treated (NTR). Testing for memory persistence occurred 7 days after the last training session (PHACR, SALR and NTRR Groups). Pigeons treated with phaclofen had lower latency and higher correct choice values than saline and non-treated controls (p < 0.05). Analysis of hippocampus tissue indicated that Synapsin I-positive cell counts were higher in pigeons treated with phaclofen than in saline and non-treated controls (p < 0.05). Data indicated enhancement of consolidation and persistence of food location memory, and up-regulation of Synapsin I expression in the hippocampus of pigeons, which were related with post-training blockade of GABAB receptors.

Changes in the levels of CAM kinase II and synapsin I caused by oxidative stress in the rat brain, and its prevention by vitamin E

To define whether oxidative stress and aging induce abnormal dissociation of neurotransmitter-enclosing synaptic vesicles in rat brain nerve terminals, we assessed the activation of Ca+/calmodulin dependent protein kinase II (CAM kinase II) and changes in the levels of synapsin I, which is a synaptic vesicle-associated protein involved in the modulation of neurotransmitter release. Assessment of young rats subjected to hyperoxia-induced oxidative stress and normal aged rats revealed that synaptic CAM kinase II in the rat brain was markedly activated through oxidative stress and aging. In accordance with the activation of CAM kinase II, the levels of phosphorylated synapsin I increased significantly in nerve terminals. Furthermore, it was found that vitamin E prevents these oxidative stress-induced abnormal processes in rat nerve terminals. These results suggest that oxidative stress and aging facilitate the mobilization of neurotransmitter-enclosing synaptic vesicles from the reserve pool in the nerve terminal, thereby inducing abnormal accumulation of synaptic vesicles in the synapse, and that vitamin E inhibits this process in the brain through its antioxidative action.

synapsinⅠ参与(-)黄皮酰胺增强齿状回突触传递功能

目的观察synapsin Ⅰ在（-）黄皮酰胺促进大鼠海马齿状回突触传递功能中的作用。方法用电生理方法观察（-）黄皮酰胺对基础突触传递功能的影响；采用Western blot方法及共聚焦显微镜检测了（-）黄皮酰胺对synapsin Ⅰ磷酸化的时间、浓度依赖关系，以及确定促进synapsin Ⅰ激活的上游蛋白激酶。结果在整体动物中，（-）黄皮酰胺可明显增加海马齿状回群峰电位，并且脑室给药5min即可促进海马synapsin Ⅰ磷酸化增强，15min时皮层synapsin Ⅰ磷酸化增强最明显。0．1、1、10mμol·L^-1（-）黄皮酰胺可浓度依赖性促进PC12细胞中synapsin Ⅰ激活，且10mμol·L^-1（-）黄皮酰胺在1～2min均可激活突触体和PCI2细胞中synapsin Ⅰ。PKA抑制剂H89可抑制（-）黄皮酰胺对synapsin Ⅰ的磷酸化。结论（-）黄皮酰胺通过PKA促进synapsin Ⅰ磷酸化而增强基础突触传递活动。

Xuefu Zhuyu decoction improves neurological dysfunction by increasing synapsin expression after traumatic brain injury

Xuefu Zhuyu decoction has been used for treating traumatic brain injury and improving post-traumatic dysfunction, but its mechanism of action needs further investigation. This study established rat models of traumatic brain injury by controlled cortical impact. Rat models were intragastrically administered 9 and 18 g/kg Xuefu Zhuyu decoction once a day for 14 or 21 days. Changes in neurological function were assessed by modified neurological severity scores and the Morris water maze. Immunohistochemistry, western blot assay, and re- verse-transcription polymerase chain reaction were used to analyze synapsin protein and mRNA expression at the injury site of rats. Our results showed that Xuefu Zhuyu decoction visibly improved neurological function of rats with traumatic brain injury. These changes were accompanied by increased expression of synaptophysin, synapsin I, and postsynaptic density protein-95 protein and mRNA in a dose-de- pendent manner. These findings indicate that Xuefu Zhuyu decoction increases synapsin expression and improves neurological deficits alder traumatic brain injury.

Effects of brain-derived neurotrophic factor on synapsin expression in rat spinal cord anterior horn neurons cultured in vitro

Brain-derived neurotrophic factor （BDNF） promotes synaptic formation and functional maturation by upregulating synapsin expression in cortical and hippocampal neurons. However, it remains controversial whether BDNF affects synapsin expression in spinal cord anterior horn neurons. Wistar rat spinal cord anterior horn neurons were cultured in serum-supplemented medium containing BDNF, BDNF antibody, and Hank＇s solution for 3 days, and then synapsin I and synaptophysin protein and mRNA expression was detected. Under serum-supplemented conditions the number of surviving neurons in the spinal cord anterior horn was similar among BDNF, anti-BDNF, and control groups （P 〉 0.05）. Synapsin I and synaptophysin protein and mRNA expressions were increased in BDNF-treated neurons, but decreased in BDNF antibody-treated neurons （P 〈 0.01）. These results indicated that BDNF significantly promotes synapsin I and synaptophysin expression in in vitro-cultured rat spinal cord anterior horn neurons.

突触蛋白Synapsin在氧糖剥夺模型中的表达及意义

目的探讨Synapsin蛋白在氧糖剥夺模型中的表达变化及意义。方法 PC12细胞进行氧糖剥夺处理,建立缺血性脑损伤模型,Western blot方法检测氧糖剥夺模型细胞中Synapsin蛋白的表达。结果应用终浓度50ng/ml NGF的DMEM完全培养基培养PC12细胞,对PC12细胞进行氧糖剥夺处理,与对照组相比,氧糖剥夺(OGD)时间越长,Synapsin蛋白表达水平越低,蛋白表达的条带越淡。结论 Synapsin蛋白对PC12细胞的突出增长有促增殖作用,随氧糖剥夺时间的延长,神经细胞的神经元特性、突触功能逐渐减低。

Synapsin Polymorphisms Could Be Correlated with Stroop Simple Reaction Time Scores

Objective: The aim of this study was to research the relationship between Attention Deficit Hyperactivity Disorder (ADHD) and the synapsin III -196G>A and -631C>G polymorphisms and study their impact on neurocognition and behavior in Turkish children and adolescents. Methods: A total of 201 ADHD-diagnosed children and 100 control subjects aged between 8 and 15 years were recruited, and genetic material was obtained from saliva. In the diagnostic assessments, the KSADS- PL semi-structured interview was applied. Children with any comorbid psychiatric diagnosis (with the exclusion of oppositional defiant disorder (ODD)), medical conditions, prior psychotropic drug use history or IQ score below 80 were excluded. For the behavioral and ADHD symptom assessments, the Turgay DSM-IV Disruptive Behaviors Rating Scale, Teacher Report Form (TRF) and Child Behavior Checklist (CBCL) were completed by the parents and teachers. Neurocognitive profiles were evaluated with the CNS-Vital Signs computerized neurocognitive test battery. Results: No significant difference in ADHD prevalence was observed between subjects with the synapsin III gene -196G>A polymorphism and -631C>G polymorphisms. These polymorphisms were also not associated with subtypes of ADHD. We found a relationship between both polymorphisms and Stroop simple reaction time. Conclusion: Synapsin’s effect could be limited during childhood, but synapsin polymorphisms could be associated with Stroop simple reaction time.

EPO对Alzheimer样大鼠记忆能力及海马synapsin1蛋白表达的影响

目的探讨促红细胞生成素(EPO)对Alzheimer样大鼠记忆能力和海马synapsin 1蛋白表达的影响及作用机制。方法 48只雄性Wistar大鼠随机分为正常对照组、生理盐水(NS)组、模型组、EPO治疗组,每组12只。其中NS组双侧海马注射NS各5μl;模型组和EPO治疗组双侧海马注射凝聚态Aβ各5μl。EPO治疗组从造模当天按5000 IU/kg腹腔注射EPO,隔天一次。术后第10天Y迷宫法检测各组大鼠空间定向学习和记忆能力,透射电镜观察海马线粒体和突触结构的改变,使用Western blot技术检测各组大鼠synapsin 1蛋白水平。结果 (1)与NS组比较,模型组学习记忆能力显著下降(P<0.05);与模型组比较,EPO治疗组Y迷宫作业尝试次数减少,错误反应次数减少,全天总反应时间缩短,差异有统计学意义(P<0.05)。(2)透射电镜结果显示,正常对照组和NS组神经细胞结构完整,线粒体膜、脊完整,神经轴突和神经突触结构完整;EPO治疗组大鼠海马线粒体和神经突触基本正常;模型组大鼠海马线粒体结构破坏,线粒体肿胀,脊断裂,神经突触密度降低,突触膜增厚,突触间隙不清,突触小泡数量减少。(3)与模型组相比,EPO治疗组大鼠海马synapsin 1蛋白表达增强,差异均有统计学意义(P<0.05)。结论 EPO可以显著改善AD样大鼠的空间记忆能力,减轻Aβ对大鼠海马超微结构的破坏,其机制可能与提高synapsin1蛋白表达有关。

Effect of intravenous transplantation of bone marrow mesenchymal stem cells on neurotransmitters and synapsins in rats with spinal cord injury

Bone marrow mesenchymal stem cells were isolated, purified and cultured in vitro by Percoll density gradient centrifugation combined with the cell adherence method. Passages 3 5 bone marrow mesenchymal stem cells were transplanted into rats with traumatic spinal cord injury via the caudal vein. Basso-Beattie-Bresnahan scores indicate that neurological function of experimental rats was significantly improved over transplantation time （1-5 weeks）. Expressions of choline acetyltransferase, glutamic acid decarboxytase and synapsins in the damaged spinal cord of rats was significantly increased after transplantation, determined by immunofluorescence staining and laser confocal scanning microscopy. Bone marrow mesenchymal stem cells that had migrated into the damaged area of rats in the experimental group began to express choline acetyltransferase, glutamic acid decarboxylase and synapsins, 3 weeks after transplantation. The Basso-Beattie- Bresnahan scores positively correlated with expression of choline acetyltransferase and synapsins. Experimental findings indicate that intravenously transplanted bone marrow mesenchymal stem cells traverse into the damaged spinal cord of rats, promote expression of choline acetyltransferase, glutamic acid decarboxylase and synapsins, and improve nerve function in rats with spinal cord injury.

miR-142通过FMRP介导上调APP/PS1小鼠海马神经元PSD95和Synapsin I表达改善学习记忆能力

目的探讨miR-142通过FMRP介导调控APP/PS1小鼠海马神经元内PSD95和Synapsin I的表达及对学习记忆能力的影响。方法将10月龄APP/PS1小鼠随机分成AD组、sh-miR-NC组、sh-miR组,同月龄的C57BL/6小鼠作为Control组,利用Morris水迷宫行为学实验检测小鼠的学习记忆能力,用Western blot和免疫荧光方法检测FMRP、PSD95和Synapsin I在各组小鼠海马神经元中的表达情况。结果APP/PS1小鼠学习记忆能力明显下降;沉默miR-142明显改善APP/PS1小鼠的学习记忆能力,使APP/PS1小鼠海马神经元低表达的FMRP、PSD95和Synapisin I等蛋白逆转上调。结论miR-142通过结合FMRP上调APP/PS1小鼠海马神经元内PSD95和Synapsin I的表达水平,改善学习记忆能力。

Role of presynaptic phosphoprotein synapsin Ⅱ in schizophrenia

Synapsin Ⅱ is a member of the neuronal phosphoprotein family. These phosphoproteins are evolutionarily conserved across many organisms and are important in a variety of synaptic functions, including synaptogenesis and the regulation of neurotransmitter release. A number of genome-wide scans, meta-analyses, and genetic susceptibility studies have implicated the synapsin II gene(3p25) in the etiology of schizophrenia(SZ) and other psychiatric disorders. Further studies have found a reduction of synapsin II m RNA and protein in the prefrontal cortex in post-mortem samples from schizophrenic patients. Disruptions in the expression of this gene may cause synaptic dysfunction, which can result in neurotransmitter imbalances, likely contributing to the pathogenesis of SZ. SZ is a costly, debilitating psychiatric illness affecting approximately 1.1% of the world's population, amounting to 51 million people today. The disorder is characterized by positive(hallucinations, paranoia), negative(social withdrawal, lack of motivation), and cognitive(memory impairments, attention deficits) symptoms. This review provides a comprehensive summary of the structure, function, and involvement of the synapsin family, specifically synapsin II, in the pathophysiology of SZ and possible target for therapeutic intervention/implications.

Research progress of the synapsin 2 gene polymorphism in the pathogenesis of schizophrenia

Schizophrenia(SCZ)is the most common serious mental illness with a high disability rate and heavy social and family burdens.At present,there is no clear etiology and pathogenesis of schizophrenia.Studies have shown that the occurrence of schizophrenia may be related to the abnormality of the hypothalamic-pituitary-adrenal(HPA)axis.The LIM-homeobox gene 3(LHXS)and early growth response 1(EGR1)can affect pituitary function.Because the synapsin 2(SYN2)gene polymorphism regulates the activity of LHX3 and EGR1,it may cause the occurrence of schizophrenia.This article will review the possible involvement of SYN2 gene polymorphism in the pathogenesis of schizophrenia via regulating the activity of LHX3 and EGR1,then to afiect the HPA axis.

Acrylamide-induced Subacute Neurotoxic Effects on the Cerebral Cortex and Cerebellum at the Synapse Level in Rats

Objective To investigate acrylamide （ACR）-induced subacute neurotoxic effects on the central nervous system （CNS） at the synapse level in rats. Methods Thirty-six Sprague Dawley （SD） rats were randomized into three groups, （1） a 30 mg/kg ACR-treated group, （2） a 50 mg/kg ACR-treated group, and （3） a normal saline （NS）-treated control group. Body weight and neurological changes were recorded each day. At the end of the test, cerebral cortex and cerebellum tissues were harvested and viewed using light and electron microscopy. Additionally, the expression of Synapsin I and P-Synapsin I in the cerebral cortex and cerebellum were investigated. Results The 50 mg/kg ACR-treated rats showed a significant reduction in body weight compared with untreated individuals （P 〈 0.05）. Rats exposed to ACR showed a significant increase in gait scores compared with the NS control group （P 〈 0.05）. Histological examination indicated neuronal structural damage in the 50 mg/kg ACR treatment group. The active zone distance （AZD） and the nearest neighbor distance （NND） of synaptic vesicles in the cerebral cortex and cerebellum were increased in both the 30 mg/kg and 50 mg/kg ACR treatment groups. The ratio of the distribution of synaptic vesicles in the readily releasable pool （RRP） was decreased. Furthermore, the expression levels of Synapsin I and P-Synapsin I in the cerebral cortex and cerebellum were decreased in both the 30 mg/kg and 50 mg/kg ACR treatment groups. Conclusion Subacute ACR exposure contributes to neuropathy in the rat CNS. Functional damage of synaptic proteins and vesicles may be a mechanism of ACR neurotoxicity.

补肾活血中药对糖尿病大鼠视路SynⅠ和Nissl小体的影响

目的观察实验性糖尿病大鼠视路神经元组织形态学的病理改变,并探讨补肾活血中药复方防治实验性糖尿病大鼠视路损害的作用机理。方法选用SD大鼠,采用链脲佐菌素(streptozotocin,STZ)建立实验性糖尿病模型。实验大鼠随机分为7组:正常对照组、阴性对照组(模型组)、阳性对照Ⅰ组、阳性对照Ⅱ组、中药低、中、高剂量组。以Nissl染色法和免疫组织化学方法染色显示视网膜、外侧膝状体(external genic-ulate body,EGB)、视皮质(visual cortex,VC)中Nissl小体、突触素I(synapsin I,Syn I)的表达,应用Mias-2000图形分析系统对其进行测定和分析。结果与正常对照组相比,阴性对照组大鼠视路三级神经元的Syn I的表达强度和Nissl小体的含量均明显降低(P<0.05或P<0.01);与阴性对照组相比,中药治疗组大鼠视网膜、外侧膝状体及视皮质的Syn I表达强度和Nissl小体的含量均明显增高,其中中药高剂量组最为明显(P<0.05或P<0.01)。结论实验性糖尿病大鼠在高血糖状态持续6个月后,其视路神经元发生不同程度的退行性改变;补肾活血中药能在一定程度上恢复糖尿病大鼠视觉通路神经细胞突触的密度和分布(轴突再生),并改善其神经递质释放调节功能,从而减轻实验性糖尿病大鼠视路神经元病理损害。

Sim2基因对PC12细胞分化的影响

以pcDNA3-mSim2真核表达载体稳定转染PC12细胞,探讨位于Down综合征关键位点的Sim2基因对PC12细胞分化的影响及其机制。以倒置相差显微镜观察PC12细胞神经突起的变化;以RT-PCR方法检测神经元分化相关基因GAP43和SynapsinⅠmRNA表达水平的变化;流式细胞仪检测GAP43蛋白的表达。RT-PCR结果显示,pcDNA3-mSim2转染后,mSim2 mRNA表达明显上调;与对照组相比,转染mSim2的PC12细胞突起数量显著减少,长度明显变短;GAP43和SynapsinⅠmRNA表达水平明显降低(P<0.05);流式细胞仪检测发现,转染mSim2的PC12细胞GAP43蛋白表达水平显著降低(P<0.05)。提示Sim2基因可通过影响神经元的分化参与Down综合征的发生。

Beta 2-adrenergic receptor activation enhances neurogenesis in Alzheimer's disease mice

Impaired hippocampal neurogenesis is one of the early pathological features of Alzheimer＇s disease. Enhancing adult hippocampal neuro- genesis has been pursued as a potential therapeutic strategy for Alzheimer＇s disease. Recent studies have demonstrated that environmental novelty activates β2-adrenergic signaling and prevents the memory impairment induced by amyloid-β oligomers. Here, we hypothesized that β2-adrenoceptor activation would enhance neurogenesis and ameliorate memory deficits in Alzheimer＇s disease. To test this hypothe- sis, we investigated the effects and mechanisms of action of β2-adrenoceptor activation on neurogenesis and memory in amyloid precursor protein/presenilin 1 （APP/PS1） mice using the agonist clenbuterol （intraperitoneal injection, 2 mg/kg）. We found that β2-adrenoceptor ac- tivation enhanced hippocampal neurogenesis, ameliorated memory deficits, and increased dendritic branching and the density of dendritic spines, lhese effects were associated with the upregulation of postsynaptic density 95, synapsin 1 and synaptophysin in APP/PS1 mice. Furthermore, β2-adrenoceptor activation decreased cerebral amyloid plaques by decreasing APP phosphorylation at Thr668. These findings suggest that β2-adrenoceptor activation enhances neurogenesis and ameliorates memory deficits in APP/PS 1 mice.

The effects of Xingnao Jieyu capsules on post-stroke depression are similar to those of fluoxetine

The Xingnao Jieyu capsule has been shown to effectively relieve neurologic impairments and les- sen depression. It remains poorly understood whether this capsule can be used to treat post-stroke depression. Thus, in the present study, we established a rat model of post-stroke depression using left middle cerebral artery occlusions in combination of chronic unpredictable stress and solitary housing during development. Experimental rats received intragastric perfusion with 0.82, 0.41, and 0.20 g/kg Xingnao Jieyu capsules separately dissolved in 2 mL distilled water. Fluoxetine served as a positive control. The treatment was conducted over 28 days. Sugar water consumption test, open-field test, real-time fluorescent quantitative PCR and immunohistochemical staining results demonstrated that intragastric perfusion with various doses of Xingnao Jieyu capsules increased sugar water consumption, voluntary behaviors and synaptotagmin mRNA and protein expression in rats with post-stroke depression. These therapeutic effects were similar to those of fluoxetine. These results indicate that Xingnao Jieyu capsules upregulate synaptotagmin expression in hip pocampi of rats with post-stroke depression, and exert antidepressant effects.

Paired associated magnetic stimulation promotes neural repair in the rat middle cerebral artery occlusion model of stroke

Paired associative stimulation has been used in stroke patients as an innovative recovery treatment.However,the mechanisms underlying the therapeutic effectiveness of paired associative stimulation on neurological function remain unclear.In this study,rats were randomly divided into middle cerebral occlusion model(MCAO)and paired associated magnetic stimulation(PAMS)groups.The MCAO rat model was produced by middle cerebral artery embolization.The PAMS group received PAMS on days 3 to 20 post MCAO.The MCAO group received sham stimulation,three times every week.Within 18 days after ischemia,rats were subjected to behavioral experiments—the foot-fault test,the balance beam walking test,and the ladder walking test.Balance ability was improved on days 15 and 17,and the footfault rate was less in their affected limb on day 15 in the PAMS group compared with the MCAO group.Western blot assay showed that the expression levels of brain derived neurotrophic factor,glutamate receptor 2/3,postsynaptic density protein 95 and synapsin-1 were significantly increased in the PAMS group compared with the MCAO group in the ipsilateral sensorimotor cortex on day 21.Resting-state functional magnetic resonance imaging revealed that regional brain activities in the sensorimotor cortex were increased in the ipsilateral hemisphere,but decreased in the contralateral hemisphere on day 20.By finite element simulation,the electric field distribution showed a higher intensity,of approximately 0.4 A/m^2,in the ischemic cortex compared with the contralateral cortex in the template.Together,our findings show that PAMS upregulates neuroplasticity-related proteins,increases regional brain activity,and promotes functional recovery in the affected sensorimotor cortex in the rat MCAO model.The experiments were approved by the Institutional Animal Care and Use Committee of Fudan University,China(approval No.201802173 S)on March 3,2018.

Blocking beta 2-adrenergic receptor inhibits dendrite ramification in a mouse model of Alzheimer's disease

Dendrite ramification affects synaptic strength and plays a crucial role in memory. Previous studies revealed a correlation between beta 2-adrenergic receptor dysfunction and Alzheimer＇s disease （AD）, although the mechanism involved is still poorly understood. The current study investigated the potential effect of the selective β2-adrenergic receptor antagonist, ICI 118551 （ICI）, on Aβ deposits and AD-related cognitive impairment. Morris water maze test results demonstrated that the performance of AD-transgenic （TG） mice treated with ICI （AD-TG/ICI） was significantly poorer compared with NaCl-treated AD-TG mice （AD-TG/NaCl）, suggesting that β2-adrenergic receptor blockage by ICI might reduce the learning and memory abilities of mice. Golgi staining and immunohistochemical staining revealed that blockage of the β2-adrenergic receptor by ICI treatment decreased the number of dendritic branches, and ICI treatment in AD-TG mice decreased the expression of hippocampal synaptophysin and synapsin 1. Western blot assay results showed that the blockage of β2-adrener- gic receptor increased amyloid-β accumulation by downregulating hippocampal a-secretase activity and increasing the phosphorylation of amyloid precursor protein. These findings suggest that blocking the β2-adrenergic receptor inhibits dendrite ramification of hippocampal neurons in a mouse model of AD.