Publications by authors named "Yu-Tzu Shih"

Many genes with distinct molecular functions have been linked to genetically heterogeneous amyotrophic lateral sclerosis (ALS), including SuperOxide Dismutase 1 (SOD1) and Valosin-Containing Protein (VCP). SOD1 converts superoxide to oxygen and hydrogen peroxide. VCP acts as a chaperon to regulate protein degradation and synthesis and various other cellular responses.

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Heterozygous mutations in the dual-specificity tyrosine phosphorylation-regulated kinase 1a (Dyrk1a) gene define a syndromic form of autism spectrum disorder. The synaptic and circuit mechanisms mediating DYRK1A functions in social cognition are unclear. Here, we identify a social experience-sensitive mechanism in hippocampal mossy fiber-parvalbumin interneuron (PV IN) synapses by which DYRK1A recruits feedforward inhibition of CA3 and CA2 to promote social recognition.

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Unlabelled: Heterozygous mutations in the Dual specificity tyrosine-phosphorylation-regulated kinase 1a gene define a syndromic form of Autism Spectrum Disorder. The synaptic and circuit mechanisms mediating Dyrk1a functions in social cognition are unclear. Here, we identify a social experience-sensitive mechanism in hippocampal mossy fiber-parvalbumin interneuron (PV IN) synapses by which Dyrk1a recruits feedforward inhibition of CA3 and CA2 to promote social recognition.

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Experience governs neurogenesis from radial-glial neural stem cells (RGLs) in the adult hippocampus to support memory. Transcription factors (TFs) in RGLs integrate physiological signals to dictate self-renewal division mode. Whereas asymmetric RGL divisions drive neurogenesis during favorable conditions, symmetric divisions prevent premature neurogenesis while amplifying RGLs to anticipate future neurogenic demands.

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Both genetic variations and nutritional deficiency are associated with autism spectrum disorders and other neurological disorders. However, it is less clear whether or how nutritional deficiency and genetic variations influence each other under pathogenic conditions. "Valosin-containing protein" (, also known as ) is associated with multiple neurological disorders and regulates dendritic spine formation by controlling endoplasmic reticulum formation and protein synthesis efficiency.

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Neurofibromatosis type 1 (NF1) is a dominant genetic disorder manifesting, in part, as cognitive defects. Previous study indicated that neurofibromin (NF1 protein) interacts with valosin-containing protein (VCP)/P97 to control dendritic spine formation, but the mechanism is unknown. Here, using Nf1 mice and transgenic mice overexpressing wild-type Vcp/p97, we demonstrate that neurofibromin acts with VCP to control endoplasmic reticulum (ER) formation and consequent protein synthesis and regulates dendritic spine formation, thereby modulating contextual fear memory and social interaction.

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While PTEN-induced kinase 1 (PINK1) is well characterized for its role in mitochondrial homeostasis, much less is known concerning its ability to prevent synaptodendritic degeneration. Using unbiased proteomic methods, we identified valosin-containing protein (VCP) as a major PINK1-interacting protein. RNAi studies demonstrate that both VCP and its cofactor NSFL1C/p47 are necessary for the ability of PINK1 to increase dendritic complexity.

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The endoplasmic reticulum (ER) is the biggest organelle in cells and is involved in versatile cellular processes. Formation and maintenance of ER morphology are regulated by a series of proteins controlling membrane fusion and curvature. At least six different ER morphology regulators have been demonstrated to be involved in neurological disorders-including Valosin-containing protein (VCP), Atlastin-1 (ATL1), Spastin (SPAST), Reticulon 2 (RTN2), Receptor expression enhancing protein 1 (REEP1) and RAB10-suggesting a critical role of ER formation in neuronal activity and function.

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Imbalanced protein homeostasis, such as excessive protein synthesis and protein aggregation, is a pathogenic hallmark of a range of neurological disorders. Here, using expression of mutant proteins, a knockdown approach and disease mutation knockin mice, we show that VCP (valosin-containing protein), together with its cofactor P47 and the endoplasmic reticulum (ER) morphology regulator ATL1 (Atlastin-1), regulates tubular ER formation and influences the efficiency of protein synthesis to control dendritic spine formation in neurons. Strengthening the significance of protein synthesis in dendritic spinogenesis, the translation blocker cyclohexamide and the mTOR inhibitor rapamycin reduce dendritic spine density, while a leucine supplement that increases protein synthesis ameliorates the dendritic spine defects caused by Vcp and Atl1 deficiencies.

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Dendritic spines are the location of excitatory synapses in the mammalian nervous system and are neuron-specific subcellular structures essential for neural circuitry and function. Dendritic spine morphology is determined by the F-actin cytoskeleton. F-actin remodeling must coordinate with different stages of dendritic spinogenesis, starting from dendritic filopodia formation to the filopodia-spines transition and dendritic spine maturation and maintenance.

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San-Huang-Xie-Xin-Tang (SHXT), composed of Coptidis rhizoma, Scutellariae radix, and Rhei rhizoma, is a traditional Chinese medicine used for complementary and alternative therapy of cardiovascular and neurodegenerative diseases via its anti-inflammatory and antioxidative effects. The aim of this study is to investigate the protective effects of SHXT in the 1-methyl-4-phenylpyridinium (MPP(+))/1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) models of Parkinson's disease. Rat primary mesencephalic neurons and mouse Parkinson disease model were used in this study.

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Inclusion body myopathy with Paget disease of bone and frontotemporal dementia (IBMPFD) is an autosomal dominant disorder characterized by progressive myopathy that is often accompanied by bone weakening and/or frontotemporal dementia. Although it is known to be caused by mutations in the gene encoding valosin-containing protein (VCP), the underlying disease mechanism remains elusive. Like IBMPFD, neurofibromatosis type 1 (NF1) is an autosomal dominant disorder.

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Inflammation and oxidative stress play important roles in the pathogenesis of neurodegenerative disorders such as stroke, traumatic injury, Parkinson disease, and Alzheimer disease. Paeonol, a natural compound extracted from Moutan cortex, is a potent anti-inflammatory and antioxidative agent. The aim of this study was to investigate the neuroprotective mechanisms of paeonol on lipopolysaccharide (LPS)-induced inflammation in rat primary microglia and 6-hydroxydopamine-induced oxidative damage in cortical neurons.

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Dengue viruses (DENVs) generally induce apoptosis in mammalian cells but cause only minor damage in mosquito cells. To find genes involved in determining the cell fate, datasets derived from expressed sequence tags (ESTs) of C6/36 cells with and without infection were established. Of overexpressed genes found in infected dataset, chaperone proteins were validated significantly upregulated in C6/36 cells at 24 hpi.

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Background: Dengue virus, a mosquito-borne flavivirus, is the etiological agent of dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. It generally induces apoptosis in mammalian cells, but frequently results in persistent infection in mosquito cells. That mechanism remains to be explored.

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Arecoline, an areca nut alkaloid, has been noted for its potential cognition-enhancing effects in patients with Alzheimer dementia. However, it has been confirmed that areca nut use is associated with oral and pharyngeal cancers. In addition, arecoline is genotoxic and cytotoxic both in vitro and in vivo through oxidative stress-dependent mechanisms.

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Polyalthia longifolia var. pendula is used as an antipyretic agent in indigenous systems of medicine. Microglia-mediated inflammation plays an important role in the pathway leading to neuronal cell death in a number of neurodegenerative diseases.

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San-Huang-Xie-Xin-Tang (SHXT), composed of Coptidis rhizoma, Scutellariae radix and Rhei rhizoma, is a traditional Chinese herbal medicine used to treat gastritis, gastric bleeding and peptic ulcers. This study investigated the neuroprotective effects of SHXT on microglia-mediated neurotoxicity using co-cultured lipopolysaccharide (LPS)-activated microglia-like BV-2 cells with neuroblastoma SH-SY5Y cells. Effects of SHXT on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity were also examined in SH-SY5Y cells.

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Objective: To investigate the in vitro effects of H. pylori-conditioned medium (HCM) from gastric epithelial AGS cell cultures on microglia and neuronal cells.

Material: H.

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Fifty-two 2-benzoylaminobenzoate analogs were synthesized and subjected to anti-platelet aggregation assay using arachidonic acid (AA), collagen (Col), thrombin (Thr), and U46619 as inducers. The results revealed that most of 2-benzoylaminobenzoic acid derivatives showed a selectively inhibitory effect on AA-induced platelet aggregation. As a result of the 2-benzoylaminobenzoic acid derivatives (18, 44, and 46), there were no inhibitory effects on platelet aggregation induced by U46619, but these elicited an inhibitory effect on thromboxane B(2) formation at 1.

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Many herbal medicines and dietary supplements sold as aids to improve memory or treat neurodegenerative diseases or have other favorable effects on the CNS contain a catechol or similar 1,2-dihydroxy aromatic moiety in their structure. As an approach to isolate and examine the neuroprotective properties of catechols, a simple catechol 4-t-Butylcatechol (TBC) has been used as a model. In this study, we investigated the effects of TBC on lipopolysaccharide (LPS)-activated microglial-induced neurotoxicity by using the in vitro model of coculture murine microglial-like cell line HAPI with the neuronal-like human neuroblastoma cell line SH-SY5Y.

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Helicobacter pylori infection leads to gastroduodenal inflammation, peptic ulceration, gastric lymphoma and gastric cancer. Certain herbal remedies have been used to treat gastric disease. In this study, we examined the anti-inflammatory effect of San-Huang-Xie-Xin-Tang (SHXT) and its main component baicalin on Helicobacter pylori-infected human gastric epithelial AGS cell.

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Dengue (Den) viruses cause apoptosis in mammalian cells, but usually result in high progeny yields without evident damage in mosquito cells. By using subtractive hybridization, 13 potentially virus-induced genes were selected in Den-2 virus-infected Aedes albopictus C6/36 cells. Based on semi-quantitative and real-time RT-PCR, one novel gene, named C189, was significantly upregulated in infected C6/36 cells.

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