目的观察5肽类似物165对老年性痴呆(Alzhei mer disease,AD)模型大鼠学习记忆能力及突触后致密区蛋白95(postsynaptic density95,PSD95)和骨架蛋白Shank1表达的影响。方法将45只大鼠随机分为正常对照组、模型组和5肽类似物165治疗组,模...目的观察5肽类似物165对老年性痴呆(Alzhei mer disease,AD)模型大鼠学习记忆能力及突触后致密区蛋白95(postsynaptic density95,PSD95)和骨架蛋白Shank1表达的影响。方法将45只大鼠随机分为正常对照组、模型组和5肽类似物165治疗组,模型组和治疗组大鼠按体重3mg/kg行双侧侧脑室链脲佐菌素(streptozotocin,STZ)注射,第3天重复注射建立AD模型,对照组以人工脑脊液代替STZ。术后21d治疗组按体重0.34mg/(kg.d)给予APP5肽类似物165灌胃干预,其余两组以蒸馏水代替。3周后应用Morris水迷宫、免疫组织化学和Western blotting方法检测大鼠的学习记忆能力及PSD95和Shank1的表达。结果5肽类似物165治疗组大鼠的平均游泳时间较模型组明显缩短(P<0.01),且海马PSD95和Shank1阳性神经细胞数及PSD95和Shank1蛋白表达较模型组明显增加(P<0.05)。结论5肽类似物165可显著提高大鼠学习记忆能力,增加大鼠海马PSD95和Shank1表达,表明其对突触功能和可塑性具改善作用。展开更多
Our previous study showed that when glutamate receptor （GluR）6 C terminus-containing peptide conjugated with the human immunodeficiency virus Tat protein （GluR6）-9c is delivered into hippocampal neurons in a brain...Our previous study showed that when glutamate receptor （GluR）6 C terminus-containing peptide conjugated with the human immunodeficiency virus Tat protein （GluR6）-9c is delivered into hippocampal neurons in a brain ischemic model, the activation of mixed lineage kinase 3 （MLK3） and c-Jun NH2-terminal kinase （JNK） is inhibited via GluR6-postsynaptic density protein 95 （PSD95）. In the present study, we investigated whether the recombinant adenovirus （Ad） carrying GluR6c could suppress the assembly of the GluR6-PSD95-MLK3 signaling module and decrease neuronal cell death induced by kainate in hippocampal CA1 subregion. A seizure model in Sprague-Dawley rats was induced by intraperitoneal injections of kainate. The effect of Ad- Glur6-9c on the phosphorylation of INK, MLK3 and mitogen-activated ldnase kinase 7 （MKK7） was observed with western immunoblots and immunohistochemistry. Our findings revealed that overexpression of GluR6c inhibited the interaction of GluR6 with PSD95 and prevented the kainate-induced activation of INK, MLK3 and MKK7. Furthermore, kainate-mediated neuronal cell death was significantly suppressed by GluR6c. Taken together, GluR6 may play a pivotal role in neuronal cell death.展开更多
Objective： Though sevoflurane has been widely used as an anesthetic in surgery, recent studies have shown that exposure to sevoflurane alone could lead to postoperative cognitive dysfunction （POCD）, of which the me...Objective： Though sevoflurane has been widely used as an anesthetic in surgery, recent studies have shown that exposure to sevoflurane alone could lead to postoperative cognitive dysfunction （POCD）, of which the mechanisms still remain largely unknown. The medial prefrontal cortex （mPFC） is known to be implicated in various cognitive impairments, including working memory and attentional processes. In the present study, we tried to identify dysregulated gene expression in mPFC and investigate the underlying mechanisms involved in POCD. Methods： Behavioral tests, including elevated plus-maze, O-maze, and Y-maze tests, were performed on Wistar rats exposed to sevoflurane. Whole-genome mRNA profiling of mPFC from Wistar rats after exposure to sevoflurane was carried out. Real-time polymerase chain reaction （PCR） was done to verify the differentially expressed genes. Results： Significant impairment of working memory of rats after exposure to sevoflurane was observed. A total of 119 of 7319 detected mRNAs showed significantly different expression between rats with and without sevoflurane exposure （fold change （FC）〉2.0, P〈0.05, and false discovery rate （FDR）〈0.05）, among which 74 mRNAs were down-regulated and 45 mRNAs were up-regulated. Postsynaptic density-95 （PSD95, also named DLG4） showed the most significantly de- creased expression in mPFC and further investigation indicated that PSD95 expression level was correlated with spatial working memory performance. Conclusions： Our study revealed that PSD95 might be involved in the mecha- nism of POCD, which could provide clues for preventing POCD in clinical operations.展开更多
Autism spectrum disorder（ASD） is a neurodevelopmental disorder characterized by high heritability. Recently, autism, the most profound form of ASD, has been increasingly attributed to synaptic abnormalities. Postsyn...Autism spectrum disorder（ASD） is a neurodevelopmental disorder characterized by high heritability. Recently, autism, the most profound form of ASD, has been increasingly attributed to synaptic abnormalities. Postsynaptic density 95（PSD95）, encoding PSD protein-95, was found essential for synaptic formation, maturation and plasticity at a PSD of excitatory synapse. It is possibly a crucial candidate gene for the pathogenesis of ASD. To identify the relationship between the rs13331 of PSD95 gene and ASD, we performed a case-control study in 212 patients and 636 controls in a Chinese population by using a polymerase chain reaction-restriction fragment length polymerase（PCR-RFLP） assay. The results showed that in genetic analysis of the heterozygous model, an association between the T allele of the rs13331 and ASD was found in the dominant model（OR=1.709, 95% CI 1.227–2.382, P=0.002） and the additive model（OR=1.409, 95% CI=1.104–1.800, P=0.006）. Our data indicate that the genetic mutation C〉T at the rs13331 in the PSD95 gene is strikingly associated with an increased risk of ASD.展开更多
Objective To observe the effects of PSD95 gene specific siRNAs on neuropathic pain relief, neuron viability, and postsynaptic calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) phosphorylation in vitro and in...Objective To observe the effects of PSD95 gene specific siRNAs on neuropathic pain relief, neuron viability, and postsynaptic calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) phosphorylation in vitro and in vivo. Methods Gene-specific siRNAs of rat PSD95 were synthesized chemically for transfection. Adult male Sprague-Dawley (SD) rats were randomly divided into 3 groups: nave group (n=6), sham group (n=6), and sciatic nerve chronic constriction injury (CCI) group (n=24). The CCI group was further divided into 4 groups (n=6 in each group), which were pretreated with normal saline, transfection vehicle, negative control siRNAs, and PSD95 gene specific siRNAs respectively. All the subgroups received corresponding agents intrathecally for 3 days, started one day before the CCI of sciatic nerve. Both mechanical allodynia and thermal hyperalgesia were measured on post-operative day 3 and 7. PSD95 gene silenced NG108-15 cells were further stimulated by glutamate, with the cell viability and the expression/phosphorylation of CaMKIIα measured by MTT cell proliferation assay and Western blot, respectively. Results The siRNAs decreased PSD95 mRNA level significantly both in vivo and in vitro. Neuropathic pain rats pretreated with PSD95 gene specific siRNAs exhibited significant elevation in the mechanical withdrawal threshold and paw withdrawal thermal latency, without affecting the baseline nociception. PSD95 gene silencing enhanced neuronal tolerance against the glutamate excitotoxicity, meanwhile the phosphorylation of CaMKIIα Thr286 was attenuated. Conclusion Pre-emptive administration of PSD95 gene specific siRNAs may attenuate the central sensitization CaMKIIα-related signaling cascades, leading to the relief of neuropathic pain.展开更多
The rapid actions of androgen on synaptic plasticity have been extensively studied.However,the underlying mechanisms remain controversial.In this study,we used mouse hippocampal neuron cell line HT22 cells as a cell r...The rapid actions of androgen on synaptic plasticity have been extensively studied.However,the underlying mechanisms remain controversial.In this study,we used mouse hippocampal neuron cell line HT22 cells as a cell research model to investigate whether Ca^(2+)/CaMKII mediates androgen rapid actions on synaptic plasticity,especially for synaptic protein PSD95 expression.Using calcium imaging,we verified incubation with 100 nmol/L testosterone for 20 min had the most significant effect on intracellular Ca^(2+)level.In addition,the depolarization of resting membrane potential after testosterone stimulation was observed by patch clamp.We found that the depolarization of resting membrane potential was to-40 mV.展开更多
文摘目的观察5肽类似物165对老年性痴呆(Alzhei mer disease,AD)模型大鼠学习记忆能力及突触后致密区蛋白95(postsynaptic density95,PSD95)和骨架蛋白Shank1表达的影响。方法将45只大鼠随机分为正常对照组、模型组和5肽类似物165治疗组,模型组和治疗组大鼠按体重3mg/kg行双侧侧脑室链脲佐菌素(streptozotocin,STZ)注射,第3天重复注射建立AD模型,对照组以人工脑脊液代替STZ。术后21d治疗组按体重0.34mg/(kg.d)给予APP5肽类似物165灌胃干预,其余两组以蒸馏水代替。3周后应用Morris水迷宫、免疫组织化学和Western blotting方法检测大鼠的学习记忆能力及PSD95和Shank1的表达。结果5肽类似物165治疗组大鼠的平均游泳时间较模型组明显缩短(P<0.01),且海马PSD95和Shank1阳性神经细胞数及PSD95和Shank1蛋白表达较模型组明显增加(P<0.05)。结论5肽类似物165可显著提高大鼠学习记忆能力,增加大鼠海马PSD95和Shank1表达,表明其对突触功能和可塑性具改善作用。
基金supported by the National Natural Science Foundation of China,No.30800309,81372172the Educational Science Foundation of Jiangsu Province,China,No.10KJB350005+2 种基金the Xuzhou Science Foundation in China,No.XZZD1153the President Special Grant of Xuzhou Medical College in China,No.09KJZ20a grant from the Zhenxing Project Foundation of XZMC
文摘Our previous study showed that when glutamate receptor （GluR）6 C terminus-containing peptide conjugated with the human immunodeficiency virus Tat protein （GluR6）-9c is delivered into hippocampal neurons in a brain ischemic model, the activation of mixed lineage kinase 3 （MLK3） and c-Jun NH2-terminal kinase （JNK） is inhibited via GluR6-postsynaptic density protein 95 （PSD95）. In the present study, we investigated whether the recombinant adenovirus （Ad） carrying GluR6c could suppress the assembly of the GluR6-PSD95-MLK3 signaling module and decrease neuronal cell death induced by kainate in hippocampal CA1 subregion. A seizure model in Sprague-Dawley rats was induced by intraperitoneal injections of kainate. The effect of Ad- Glur6-9c on the phosphorylation of INK, MLK3 and mitogen-activated ldnase kinase 7 （MKK7） was observed with western immunoblots and immunohistochemistry. Our findings revealed that overexpression of GluR6c inhibited the interaction of GluR6 with PSD95 and prevented the kainate-induced activation of INK, MLK3 and MKK7. Furthermore, kainate-mediated neuronal cell death was significantly suppressed by GluR6c. Taken together, GluR6 may play a pivotal role in neuronal cell death.
基金supported by the Anhui Education Department(No.KJ2015 B004by)the Bengbu Medical College(No.BYKY1424ZD),China
文摘Objective： Though sevoflurane has been widely used as an anesthetic in surgery, recent studies have shown that exposure to sevoflurane alone could lead to postoperative cognitive dysfunction （POCD）, of which the mechanisms still remain largely unknown. The medial prefrontal cortex （mPFC） is known to be implicated in various cognitive impairments, including working memory and attentional processes. In the present study, we tried to identify dysregulated gene expression in mPFC and investigate the underlying mechanisms involved in POCD. Methods： Behavioral tests, including elevated plus-maze, O-maze, and Y-maze tests, were performed on Wistar rats exposed to sevoflurane. Whole-genome mRNA profiling of mPFC from Wistar rats after exposure to sevoflurane was carried out. Real-time polymerase chain reaction （PCR） was done to verify the differentially expressed genes. Results： Significant impairment of working memory of rats after exposure to sevoflurane was observed. A total of 119 of 7319 detected mRNAs showed significantly different expression between rats with and without sevoflurane exposure （fold change （FC）〉2.0, P〈0.05, and false discovery rate （FDR）〈0.05）, among which 74 mRNAs were down-regulated and 45 mRNAs were up-regulated. Postsynaptic density-95 （PSD95, also named DLG4） showed the most significantly de- creased expression in mPFC and further investigation indicated that PSD95 expression level was correlated with spatial working memory performance. Conclusions： Our study revealed that PSD95 might be involved in the mecha- nism of POCD, which could provide clues for preventing POCD in clinical operations.
基金supported by grants from the Fundamental Research Funds for the Central Universities(HUST No.2015TS096)Hubei Province Health and Family Planning Scientific Research Project(No.WJ2015MB019)a funding program of Science and Technology Projects of Shenzhen(No.JCYJ20150403142731429)
文摘Autism spectrum disorder（ASD） is a neurodevelopmental disorder characterized by high heritability. Recently, autism, the most profound form of ASD, has been increasingly attributed to synaptic abnormalities. Postsynaptic density 95（PSD95）, encoding PSD protein-95, was found essential for synaptic formation, maturation and plasticity at a PSD of excitatory synapse. It is possibly a crucial candidate gene for the pathogenesis of ASD. To identify the relationship between the rs13331 of PSD95 gene and ASD, we performed a case-control study in 212 patients and 636 controls in a Chinese population by using a polymerase chain reaction-restriction fragment length polymerase（PCR-RFLP） assay. The results showed that in genetic analysis of the heterozygous model, an association between the T allele of the rs13331 and ASD was found in the dominant model（OR=1.709, 95% CI 1.227–2.382, P=0.002） and the additive model（OR=1.409, 95% CI=1.104–1.800, P=0.006）. Our data indicate that the genetic mutation C〉T at the rs13331 in the PSD95 gene is strikingly associated with an increased risk of ASD.
基金Supported by National Natural Science Foundation of China (30672029, 30872436)Central Committee Foundation of Health Care Program (B2009B076)
文摘Objective To observe the effects of PSD95 gene specific siRNAs on neuropathic pain relief, neuron viability, and postsynaptic calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) phosphorylation in vitro and in vivo. Methods Gene-specific siRNAs of rat PSD95 were synthesized chemically for transfection. Adult male Sprague-Dawley (SD) rats were randomly divided into 3 groups: nave group (n=6), sham group (n=6), and sciatic nerve chronic constriction injury (CCI) group (n=24). The CCI group was further divided into 4 groups (n=6 in each group), which were pretreated with normal saline, transfection vehicle, negative control siRNAs, and PSD95 gene specific siRNAs respectively. All the subgroups received corresponding agents intrathecally for 3 days, started one day before the CCI of sciatic nerve. Both mechanical allodynia and thermal hyperalgesia were measured on post-operative day 3 and 7. PSD95 gene silenced NG108-15 cells were further stimulated by glutamate, with the cell viability and the expression/phosphorylation of CaMKIIα measured by MTT cell proliferation assay and Western blot, respectively. Results The siRNAs decreased PSD95 mRNA level significantly both in vivo and in vitro. Neuropathic pain rats pretreated with PSD95 gene specific siRNAs exhibited significant elevation in the mechanical withdrawal threshold and paw withdrawal thermal latency, without affecting the baseline nociception. PSD95 gene silencing enhanced neuronal tolerance against the glutamate excitotoxicity, meanwhile the phosphorylation of CaMKIIα Thr286 was attenuated. Conclusion Pre-emptive administration of PSD95 gene specific siRNAs may attenuate the central sensitization CaMKIIα-related signaling cascades, leading to the relief of neuropathic pain.
文摘The rapid actions of androgen on synaptic plasticity have been extensively studied.However,the underlying mechanisms remain controversial.In this study,we used mouse hippocampal neuron cell line HT22 cells as a cell research model to investigate whether Ca^(2+)/CaMKII mediates androgen rapid actions on synaptic plasticity,especially for synaptic protein PSD95 expression.Using calcium imaging,we verified incubation with 100 nmol/L testosterone for 20 min had the most significant effect on intracellular Ca^(2+)level.In addition,the depolarization of resting membrane potential after testosterone stimulation was observed by patch clamp.We found that the depolarization of resting membrane potential was to-40 mV.
