ABSTRACT
The complete transformation from narrow peak emission of Eu3+ to broadband emission of Eu2+ was first realized in La1-xSr2+xAl1-xSixO5:Eu series solutions relying on crystal field engineering and adjustment of synthesis parameters. The original red phosphor La0.97Sr2AlO5:0.03Eu3+peaks at 703 nm originated from 5D0 â7F4 transition of Eu3+ under 395 nm excitation. As the x value regularly increased, Sr2SiO4-type green phosphor La0.17Sr2.8Al0.2Si0.8O5:0.03Eu2+ was synthesized at x = 0.8, which can be efficiently excited by UV/blue light chips. Moreover, when x > 0.975, Sr3SiO5:Eu2+ type broadband orange phosphor Sr2.945Al0.025Si0.975O5:0.03Eu2+ with excellent thermal stability (91.3% peak intensity at 150 °C) was obtained. Variations in the crystal structure, phase, and luminescence properties were studied in detail. We hope this work can provide a reference that solid solution between distinct but structurally related systems is a strategy to explore the possible phosphors for phosphor-converted light-emitting diodes.
ABSTRACT
CSTB has been reported to be associated with the pathogenesis of many malignant tumors, especially hepatocellular carcinoma (HCC). However, how the expression of this gene is regulated is largely unknown. We initially cloned and analyzed the promoter region of the CSTB gene by luciferase assay and the Sp3 binding site (CCCCGCCCCGCG) was found in it. The results of electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) experiments verified that the transcription factor, Sp3 could bind to the " CCCCGCCCCGCG â³ site of the CSTB gene promoter. We showed that the overexpression of Sp3 significantly increased the endogenous mRNA and protein expression levels of CSTB, whereas knockdown of Sp3 decreased the mRNA and protein expression levels according to quantitative real-time PCR (qRTâPCR) and western blotting. In conclusion, CSTB gene expression is closely regulated by transcription factor Sp3, which may be a potential mechanism for the dysregulation of CSTB expression in HCC.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Transcriptional Activation , Carcinoma, Hepatocellular/genetics , Sp3 Transcription Factor/genetics , Liver Neoplasms/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Gene Expression , Sp1 Transcription Factor/genetics , Sp1 Transcription Factor/metabolismABSTRACT
Generalized pustular psoriasis (GPP) is an autoinflammatory skin disease whose pathogenesis has not yet been fully elucidated. Alpha-1-antichymotrypsin(ACT) is a protein encoded by the SERPINA3 gene and an inhibitor of cathepsin G. One study of a European sample suggested that the loss of ACT function caused by SERPINA3 mutation is implicated in GPP. However, the role of SERPINA3 in the pathogenesis of GPP in other ethnic populations is unclear. To explore this, seventy children with GPP were performed next-generation sequencing to identify rare variants in the SERPINA3 gene. Bioinformatic analysis and functional tests were used to determine the effects of the variants, and a comprehensive analysis was performed to determine the pathogenicity of the variants and whether they are associated with GPP. One rare deletion and three rare missense variants were identified in the SERPINA3 gene in GPP. The deletion variant c.1246_1247del was found to result in a mutant protein with an extension of 10 amino acids and a C-terminal of 20 amino acids that was completely different from the wild-type. This mutant was found to impede secretion of ACT, thus failing to function as an inhibitor of cathepsin G. Two missense variants were found to reduce the ability of ACT to inhibit cathepsin G enzymatic activity. The association analysis suggested that the deletion variant is associated with GPP. This study identified four rare novel mutations of SERPINA3 and demonstrated that three of these mutations result in loss of function, contributing to the pathogenesis of pediatric-onset GPP in the Asian population.
Subject(s)
Psoriasis , Serpins , Skin Diseases , Child , Humans , Interleukins/genetics , Interleukins/metabolism , Cathepsin G/genetics , Psoriasis/drug therapy , Psoriasis/genetics , Mutation , Serpins/geneticsABSTRACT
BACKGROUND: Astrocytes are essential for synaptic transmission, and their dysfunction can result in neuropsychiatric disorders such as anxiety and depression. Many studies have shown that global knockout of Melatonin receptor 2 (Mtnr1b) is associated with the development of various mental disorders. AIM: This study aimed to investigate the effects of astrocyte ablation of Mtnr1b on cognitive function and anxiety-like behavior in mice, as well as the potential biological mechanisms. METHODS: A conditional Cre-loxP system allowing deletion of Mtnr1b from astrocytes was developed to investigate the specific role Mtnr1b. Control and Mtnr1b cKOðºððð mice were selected for cognitive function behavioral testing (Morris water maze test, novel object recognition test) and emotion-related behavioral testing (open field, elevated plus maze). After testing, brain tissue was collected and examined by immunofluorescence for the expression of neuronal nuclei (NeuN), glutamate decarboxylase 67 (GAD67), and vesicular glutamate transporter 1 (vGluT1). RNA-seq was performed on hippocampal tissue from control and Mtnr1b cKOðºððð mice to identify differentially expressed genes. Additional confirmation of differential gene expression was performed using real-time quantitative polymerase chain reaction (qRT-PCR). RESULTS: Mtnr1b cKOðºððð mice were not significantly different from control mice in the Morris water maze and novel object recognition tests. Results from the open field and elevated plus maze tests showed that Mtnr1b cKOðºððð mice exhibited significantly more anxiety-like behavior than did controls. Immunofluorescence revealed that the number of mature neurons did not differ significantly between Mtnr1b cKOðºððð mice and controls. The expression of GAD67 in the hippocampal CA1 and CA3 areas of Mtnr1b cKOðºððð mice was significantly lower than in the control group, but no significant difference was detected for vGluT1 expression. RNA-seq and qRT-PCR results showed that Mtnr1b knockout in astrocytes led to a decrease in the levels of gamma-aminobutyric acid sub-type A (GABAA) receptors and Kir2.2. CONCLUSIONS: The astrocyte-specific knockout in Mtnr1b cKOðºððð mice results in anxiety-like behavior, which is caused by down-regulation of gamma-aminobutyric acid-ergic (GABAergic) synaptic function.
Subject(s)
Astrocytes , Mental Disorders , Receptor, Melatonin, MT2 , Animals , Male , Mice , Anxiety , Astrocytes/metabolism , gamma-Aminobutyric Acid/metabolism , Mental Disorders/metabolism , Neurons/metabolism , Receptor, Melatonin, MT2/geneticsABSTRACT
MMP13 (matrix metallopeptidase 13) plays a key role in bone metabolism and cancer development, but has no known functions in Alzheimer's disease. In this study, we used high-throughput small molecule screening in SH-SY5Y cells that stably expressed a luciferase reporter gene driven by the BACE1 (ß-site amyloid precursor protein cleaving enzyme 1) promoter, which included a portion of the 5' untranslated region (5'UTR). We identified that CL82198, a selective inhibitor of MMP13, decreased BACE1 protein levels in cultured neuronal cells. This effect was dependent on PI3K (phosphatidylinositide 3-kinase) signalling, and was unrelated to BACE1 gene transcription and protein degradation. Further, we found that eukaryotic translation initiation factor 4B (eIF4B) played a key role, as the mutation of eIF4B at serine 422 (S422R) or deletion of the BACE1 5'UTR attenuated MMP13-mediated BACE1 regulation. In APPswe/PS1E9 mice, an animal model of Alzheimer's disease, hippocampal Mmp13 knockdown or intraperitoneal CL82198 administration reduced BACE1 protein levels and the related amyloid-ß precursor protein processing, amyloid-ß load and eIF4B phosphorylation, whereas spatial and associative learning and memory performances were improved. Collectively, MMP13 inhibition/CL82198 treatment exhibited therapeutic potential for Alzheimer's disease, via the translational regulation of BACE1.
Subject(s)
Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/metabolism , Aspartic Acid Endopeptidases/metabolism , Benzofurans/therapeutic use , Cognitive Dysfunction/drug therapy , Matrix Metalloproteinase 13/metabolism , Matrix Metalloproteinase Inhibitors/therapeutic use , Morpholines/therapeutic use , Alzheimer Disease/genetics , Amyloid beta-Protein Precursor/genetics , Animals , Cells, Cultured , Eukaryotic Initiation Factors/genetics , Gene Knockdown Techniques , Hippocampus/metabolism , Humans , Mice , Mice, Transgenic , Mutation , Oligopeptides/genetics , Phosphatidylinositol 3-Kinases/metabolism , RatsSubject(s)
Genetic Association Studies , Genetic Predisposition to Disease , Interleukins/genetics , Mutation , Psoriasis/diagnosis , Psoriasis/genetics , Age of Onset , Alleles , Biopsy , Child , DNA Mutational Analysis , Female , Genetic Association Studies/methods , Genotype , Humans , Interleukins/chemistry , Interleukins/metabolism , Phenotype , Proteolysis , Psoriasis/therapy , Skin/pathology , Symptom AssessmentABSTRACT
Neurexins are neuron-specific synaptic proteins, and abnormal structure of Neurexin1ß is closely associated with autism. To characterize the minimal promoter of autism-associated NRXN1ß gene and identify functional elements regulating its transcription, luciferase reporter plasmids containing different regulatory regions upstream of NRXN1ß gene were constructed. After transfecting HEK293 cells with these plasmids, the minimal promoter region of NRXN1ß gene was determined by detecting the transcriptional activity of luciferase reporter genes while the corresponding functional elements that significantly enhance or inhibit the activity of reporter genes were further screened out. To identify cis-acting elements, continuous nucleotide mutation within the functional regions and adjacent DNA sequences were generated using site-directed mutagenesis techniques and then transcriptional regulatory elements in corresponding regions were analyzed using transcription factor binding prediction tool. Our results showed for the first time that the minimal promoter region of human NRXN1ß gene is located between positions -88 and +156 (-88/+156); two regions -88/-73 and +156/+149 enhance while the region +229/+419 inhibits promoter activity. The region -84/-63 significantly enhances promoter activity as cis-acting elements, suggesting the presence of DBP and ABF1 transcription factor binding sites in this region.
Subject(s)
Autistic Disorder/genetics , Cell Adhesion Molecules, Neuronal/genetics , Nerve Tissue Proteins/genetics , Promoter Regions, Genetic , Animals , Calcium-Binding Proteins , Humans , Neural Cell Adhesion MoleculesABSTRACT
Hepatocellular carcinoma (HCC) is a significant contributor to global cancer-related deaths, leading to high mortality rates. However, the pathogenesis of HCC remains unclear. In this research, by the bioinformatics data analysis, we found that elevated CSTB expression correlated with advanced disease and predicted diminished overall survival (OS) in HCC patients. We subsequently verified the oncogenic role of CSTB as well as the potential underlying mechanisms in HCC through a series of in vitro experiments, such as CCK-8 assays, cloning assays, flow cytometry, Transwell assays, and western blotting. Our findings illustrated that the silencing of CSTB effectively suppressed cellular proliferation by inducing cell cycle arrest in the G2 phase and impaired HCC cell invasion and migration by stimulating epithelial-mesenchymal transition (EMT). Additionally, we analyzed the pathways enriched in HCC using RNA sequencing and found that the ERK/AKT/mTOR signaling pathway was related to increased CSTB expression in HCC. Finally, we confirmed the tumorigenic role of CSTB via in vivo experiments. Thus, our findings revealed that silencing CSTB inhibited the HCC progression via the ERK/AKT/mTOR signaling pathway, highlighting new perspectives for investigating the mechanisms of HCC.
ABSTRACT
SIL1, an endoplasmic reticulum (ER)-resident protein, is reported to play a protective role in Alzheimer's disease (AD). However, the effect of SIL1 on amyloid precursor protein (APP) processing remains unclear. In this study, the role of SIL1 in APP processing was explored both in vitro and in vivo. In the in vitro experiment, SIL1 was either overexpressed or knocked down in cells stably expressing the human Swedish mutant APP695. In the in vivo experiment, AAV-SIL1-EGFP or AAV-EGFP was microinjected into APP23/PS45 mice and their wild-type littermates. Western blotting (WB), immunohistochemistry, RNA sequencing (RNA-seq), and behavioral experiments were performed to evaluate the relevant parameters. Results indicated that SIL1 expression decreased in APP23/PS45 mice. Overexpression of SIL1 significantly decreased the protein levels of APP, presenilin-1 (PS1), and C-terminal fragments (CTFs) of APP in vivo and in vitro. Conversely, knockdown of SIL1 increased the protein levels of APP, ß-site APP cleavage enzyme 1 (BACE1), PS1, and CTFs, as well as APP mRNA expression in 2EB2 cells. Furthermore, SIL1 overexpression reduced the number of senile plaques in APP23/PS45 mice. Importantly, Y-maze and Morris Water maze tests demonstrated that SIL1 overexpression improved cognitive impairment in APP23/PS45 mice. These findings indicate that SIL1 improves cognitive impairment in APP23/PS45 mice by inhibiting APP amyloidogenic processing and suggest that SIL1 is a potential therapeutic target for AD by modulating APP processing.
Subject(s)
Amyloid beta-Protein Precursor , Cognitive Dysfunction , Mice, Transgenic , Animals , Amyloid beta-Protein Precursor/metabolism , Amyloid beta-Protein Precursor/genetics , Mice , Cognitive Dysfunction/metabolism , Cognitive Dysfunction/genetics , Amyloid beta-Peptides/metabolism , Presenilin-1/genetics , Presenilin-1/metabolism , Gene Expression Regulation , Alzheimer Disease/metabolism , Alzheimer Disease/genetics , HumansABSTRACT
Amyloid ß protein (Aß) is a critical factor in the pathogenesis of Alzheimer's disease (AD). Aß induces apoptosis, and gasdermin-E (GSDME) expression can switch apoptosis to pyroptosis. In this study, we demonstrated that GSDME was highly expressed in the hippocampus of APP23/PS45 mouse models compared to that in age-matched wild-type mice. Aß treatment induced pyroptosis by active caspase-3/GSDME in SH-SY5Y cells. Furthermore, the knockdown of GSDME improved the cognitive impairments of APP23/PS45 mice by alleviating inflammatory response. Our findings reveal that GSDME, as a modulator of Aß and pyroptosis, plays a potential role in Alzheimer's disease pathogenesis and shows that GSDME is a therapeutic target for AD.
Subject(s)
Alzheimer Disease , Neuroblastoma , Humans , Mice , Animals , Pyroptosis/physiology , Gasdermins , Amyloid beta-Peptides/metabolism , Caspase 3/metabolismABSTRACT
BACKGROUND: Alpha-lipoic acid (ALA) has a neuroprotective effect on neurodegenerative diseases. In the clinic, ALA can improve cognitive impairments in patients with Alzheimer's disease (AD) and other dementias. Animal studies have confirmed the anti-amyloidosis effect of ALA, but its underlying mechanism remains unclear. In particular, the role of ALA in amyloid-ß precursor protein (APP) metabolism has not been fully elucidated. OBJECTIVE: To investigate whether ALA can reduce the amyloidogenic effect of APP in a transgenic mouse model of AD, and to study the mechanism underlying this effect. METHODS: ALA was infused into 2-month-old APP23/PS45 transgenic mice for 4 consecutive months and their cognitive function and AD-like pathology were then evaluated. An ALA drug concentration gradient was applied to 20E2 cells in vitro to evaluate its effect on the expression of APP proteolytic enzymes and metabolites. The mechanism by which ALA affects APP processing was studied using GI254023X, an inhibitor of A Disintegrin and Metalloproteinase 10 (ADAM10), as well as the mitochondrial toxic drug carbonyl cyanide m-chlorophenylhydrazone (CCCP). RESULTS: Administration of ALA ameliorated amyloid plaque neuropathology in the brain tissue of APP23/PS45 mice and reduced learning and memory impairment. ALA also increased the expression of ADAM10 in 20E2 cells and the non-amyloidogenic processing of APP to produce the 83 amino acid C-terminal fragment (C83). In addition to activating autophagy, ALA also significantly promoted mitophagy. BNIP3L-knockdown reduced the mat/pro ratio of ADAM10. By using CCCP, ALA was found to regulate BNIP3L-mediated mitophagy, thereby promoting the α-cleavage of APP. CONCLUSIONS: The enhanced α-secretase cleavage of APP by ADAM10 is the primary mechanism through which ALA ameliorates the cognitive deficits in APP23/PS45 transgenic mice. BNIP3L-mediated mitophagy contributes to the anti-amyloid properties of ALA by facilitating the maturation of ADAM10. This study provides novel experimental evidence for the treatment of AD with ALA.
Subject(s)
ADAM10 Protein , Amyloid Precursor Protein Secretases , Amyloid beta-Protein Precursor , Cognitive Dysfunction , Mice, Transgenic , Mitophagy , Thioctic Acid , Animals , Thioctic Acid/pharmacology , Mitophagy/drug effects , ADAM10 Protein/metabolism , Mice , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Cognitive Dysfunction/drug therapy , Cognitive Dysfunction/metabolism , Amyloid Precursor Protein Secretases/metabolism , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Alzheimer Disease/genetics , Disease Models, Animal , Membrane Proteins/metabolism , Membrane Proteins/genetics , Neuroprotective Agents/pharmacology , Mice, Inbred C57BL , MaleABSTRACT
AIMS: Islet cell autoantigen 1 (ICA1) is involved in autoimmune diseases and may affect synaptic plasticity as a neurotransmitter. Databases related to Alzheimer's disease (AD) have shown decreased ICA1 expression in patients with AD. However, the role of ICA1 in AD remains unclear. Here, we report that ICA1 expression is decreased in the brains of patients with AD and an AD mouse model. RESULTS: The ICA1 increased the expression of amyloid precursor protein (APP), disintegrin and metalloprotease 10 (ADAM10), and disintegrin and metalloprotease 17 (ADAM17), but did not affect protein half-life or mRNA levels. Transcriptome sequencing analysis showed that ICA1 regulates the G protein-coupled receptor signaling pathway. The overexpression of ICA1 increased PKCα protein levels and phosphorylation. CONCLUSION: Our results demonstrated that ICA1 shifts APP processing to non-amyloid pathways by regulating the PICK1-PKCα signaling pathway. Thus, this study suggests that ICA1 is a novel target for the treatment of AD.
Subject(s)
Alzheimer Disease , Amyloid beta-Protein Precursor , Protein Kinase C-alpha , Signal Transduction , Amyloid beta-Protein Precursor/metabolism , Amyloid beta-Protein Precursor/genetics , Animals , Protein Kinase C-alpha/metabolism , Protein Kinase C-alpha/genetics , Signal Transduction/physiology , Humans , Alzheimer Disease/metabolism , Alzheimer Disease/genetics , Mice , Carrier Proteins/metabolism , Carrier Proteins/genetics , Nuclear Proteins/metabolism , Nuclear Proteins/genetics , Male , Mice, Transgenic , Female , Mice, Inbred C57BL , Amyloid Precursor Protein Secretases/metabolism , Amyloid Precursor Protein Secretases/genetics , Brain/metabolism , Cell Cycle ProteinsABSTRACT
BACKGROUND: Down syndrome (DS) is caused by an extra copy of all or part of chromosome 21. The patients with DS develop typical Alzheimer's disease (AD) neuropathology, indicating the role of genes on human chromosome 21 (HSA21) in the pathogenesis of AD. Purkinje cell protein 4 (PCP4), also known as brain-specific protein 19, is a critical gene located on HSA21. However, the role of PCP4 in DS and AD pathogenesis is not clear. OBJECTIVE: To explore the role of PCP4 in amyloid-ß protein precursor (AßPP) processing in AD. METHODS: In this study, we investigated the role of PCP4 in AD progression in vitro and in vivo. In vitro experiments, we overexpressed PCP4 in human Swedish mutant AßPP stable expression or neural cell lines. In vitro experiments, APP23/PS45 double transgenic mice were selected and treated with AAV-PCP4. Multiple topics were detected by western blot, RT-PCR, immunohistochemical and behavioral test. RESULTS: We found that PCP4 expression was altered in AD. PCP4 was overexpressed in APP23/PS45 transgenic mice and PCP4 affected the processing of AßPP. The production of amyloid-ß protein (Aß) was also promoted by PCP4. The upregulation of endogenous AßPP expression and the downregulation of ADAM10 were due to the transcriptional regulation of PCP4. In addition, PCP4 increased Aß deposition and neural plaque formation in the brain, and exuberated learning and memory impairment in transgenic AD model mice. CONCLUSION: Our finding reveals that PCP4 contributes to the pathogenesis of AD by affecting AßPP processing and suggests PCP4 as a novel therapeutic target for AD by targeting Aß pathology.
Subject(s)
Alzheimer Disease , Down Syndrome , Humans , Mice , Animals , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Alzheimer Disease/pathology , Amyloid beta-Peptides/metabolism , Mice, Transgenic , Brain/pathology , Down Syndrome/metabolism , Disease Models, Animal , Amyloid Precursor Protein Secretases/metabolism , Nerve Tissue Proteins/metabolismABSTRACT
Individuals with Down syndrome (DS) will inevitably develop Alzheimer disease (AD) neuropathology sometime after middle age, which may be attributable to genes triplicated in individuals with DS. The characteristics of AD neuropathology include neuritic plaques, neurofibrillary tangles, and neuronal loss in various brain regions. The mechanism underlying neurodegeneration in AD and DS remains elusive. Regulator of calcineurin 1 (RCAN1) has been implicated in the pathogenesis of DS. Our data show that RCAN1 expression is elevated in the cortex of DS and AD patients. RCAN1 expression can be activated by the stress hormone dexamethasone. A functional glucocorticoid response element was identified in the RCAN1 isoform 1 (RCAN1-1) promoter region, which is able to mediate the up-regulation of RCAN1 expression. Here we show that overexpression of RCAN1-1 in primary neurons activates caspase-9 and caspase-3 and subsequently induces neuronal apoptosis. Furthermore, we found that the neurotoxicity of RCAN1-1 is inhibited by knock-out of caspase-3 in caspase-3(-/-) neurons. Our study provides a novel mechanism by which RCAN1 functions as a mediator of stress- and Aß-induced neuronal death, and overexpression of RCAN1 due to an extra copy of the RCAN1 gene on chromosome 21 contributes to AD pathogenesis in DS.
Subject(s)
Alzheimer Disease/metabolism , Apoptosis , Caspase 3/metabolism , Down Syndrome/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Muscle Proteins/metabolism , Nerve Tissue Proteins/metabolism , Neurons/metabolism , Alzheimer Disease/etiology , Alzheimer Disease/genetics , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Animals , Caspase 3/genetics , Cerebral Cortex/metabolism , Chromosomes, Human, Pair 21/genetics , Chromosomes, Human, Pair 21/metabolism , DNA-Binding Proteins , Down Syndrome/complications , Down Syndrome/genetics , Enzyme Activation/genetics , Gene Expression Regulation/genetics , Gene Knockdown Techniques , HEK293 Cells , Humans , Intracellular Signaling Peptides and Proteins/genetics , Muscle Proteins/genetics , Nerve Tissue Proteins/genetics , Promoter Regions, Genetic/genetics , Protein Isoforms/genetics , Protein Isoforms/metabolism , Rats , Rats, WistarABSTRACT
Parkinson's disease (PD) is the second most common neurodegenerative disorders with a variable combination of motor and non-motor symptoms. Mutations in several genes including ATP13A2 (PARK9) are reported to be associated with PD. The underlying mechanism of PD is not well defined, however, both genetic and environmental causes contribute to it. ATP13A2 gene locates in chromosome 1 and contains 29 exons encoding for a protein of 1180 amino acids with 10 transmembrane domains. Abnormal gene expression has been implicated in neurodegenerative disorders. The transcriptional regulation of the ATP13A2 gene is unknown. In this report, we cloned and functionally characterized the human ATP13A2 gene promoter. We showed that the promoter region of the human ATP13A2 gene contains hypoxia response elements which can bind to transcription factor hypoxia-inducible factor 1α (HIF-1α). Hypoxia up-regulated ATP13A2 transcription via HIF-1α in HEK293 and dopaminergic MN9D cells. Our study indicates that hypoxia signaling plays a very important role in the regulation of human ATP13A2 gene expression. Further study is needed to determine the role of hypoxia in the pathogenesis of PD and its interaction with other PD causative genes, which will provide insights to the role of hypoxia and dysregulation of gene expression in Parkinson's disease.
Subject(s)
Gene Expression Regulation/physiology , Hypoxia, Brain/genetics , Hypoxia, Brain/metabolism , Parkinson Disease/genetics , Proton-Translocating ATPases/genetics , Animals , Base Sequence , Cell Line, Tumor , Chromatin Immunoprecipitation , Cloning, Molecular , DNA Primers , DNA, Complementary/biosynthesis , DNA, Complementary/genetics , HEK293 Cells , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/physiology , Mice , Molecular Sequence Data , Parkinson Disease/metabolism , Plasmids/genetics , Promoter Regions, Genetic/genetics , Real-Time Polymerase Chain ReactionABSTRACT
Elevated levels of ß-site APP cleaving enzyme 1 (BACE1) were found in the brain of some sporadic Alzheimer's disease (AD) patients; however, the underlying mechanism is unknown. BACE1 cleaves ß-amyloid precursor protein (APP) to generate amyloid ß protein (Aß), a central component of neuritic plaques in AD brains. Nuclear factor-kappa B (NF-κB) signalling plays an important role in gene regulation and is implicated in inflammation, oxidative stress and apoptosis. In this report we found that both BACE1 and NF-κB p65 levels were significantly increased in the brains of AD patients. Two functional NF-κB-binding elements were identified in the human BACE1 promoter region. We found that NF-κB p65 expression resulted in increased BACE1 promoter activity and BACE1 transcription, while disruption of NF-κB p65 decreased BACE1 gene expression in p65 knockout (RelA-knockout) cells. In addition, NF-κB p65 expression leads to up-regulated ß-secretase cleavage and Aß production, while non-steroidal anti-inflammatory drugs (NSAIDs) inhibited BACE1 transcriptional activation induced by strong NF-κB activator tumour necrosis factor-alpha (TNF-α). Taken together, our results clearly demonstrate that NF-κB signalling facilitates BACE1 gene expression and APP processing, and increased BACE1 expression mediated by NF-κB signalling in the brain could be one of the novel molecular mechanisms underlying the development of AD in some sporadic cases. Furthermore, NSAIDs could block the inflammation-induced BACE1 transcription and Aß production. Our study suggests that inhibition of NF-κB-mediated BACE1 expression may be a valuable drug target for AD therapy.
Subject(s)
Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/metabolism , Aspartic Acid Endopeptidases/metabolism , Brain/metabolism , Transcription Factor RelA/metabolism , Aged , Aged, 80 and over , Amyloid Precursor Protein Secretases/genetics , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/metabolism , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Aspartic Acid Endopeptidases/genetics , Humans , Promoter Regions, Genetic , Signal Transduction/drug effects , Transcription, Genetic/drug effects , Tumor Necrosis Factor-alpha/metabolism , Up-RegulationABSTRACT
Pituitary tumor-transforming gene 1 protein (PTTG)-interacting protein, also known as PTTG-binding factor (PBF), is encoded by a proto-oncogene PTTG1IP. PBF has been identified through its interaction with PTTG. Similar to PTTG, PBF has been implicated in the etiology of several tumors, including pituitary, thyroid, and breast cancer. PBF can induce the translocation of PTTG into the nucleus, and then lead to tumorigenesis. Studies have shown that PBF plays a vital and complex role in increasing tumor development. However, the transcriptional regulation of PTTG1IP gene remains undefined. In this study, we have cloned a 467-bp fragment of the 5' flanking region of the human PTTG1IP gene and identified the region (-212 to +7 bp) necessary for PTTG1IP gene promoter activity by luciferase assay. Electrophoretic mobility shift assay revealed PTTG1IP gene promoter containing Sp4 response elements. Overexpression of Sp4 increased PTTG1IP gene transcription and expression in HeLa cells. Our study demonstrates that Sp4 regulates PTTG1IP gene transcription and expression.
Subject(s)
Gene Expression Regulation , Intracellular Signaling Peptides and Proteins , Sp4 Transcription Factor , Humans , HeLa Cells , Intracellular Signaling Peptides and Proteins/genetics , Promoter Regions, Genetic/genetics , Transcription, Genetic , Sp4 Transcription Factor/geneticsABSTRACT
BACKGROUND: Chronic alcohol consumption can alter the structure of the central nervous system and disrupt cognitive function. Alcoholics are more likely to develop neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). However, the role of alcohol in promoting neurotoxicity and neurodegeneration remains unclear. OBJECTIVE: In this study, we aimed at estimating the effects of chronic binge alcohol exposure on brain transcriptome and behavior changes in a chronic "Drinking in the Dark" (DID) mouse model. METHODS: The adult C57BL/6J male mice were exposed to alcohol for 4 weeks. RNA-seq was applied to assess the effects of chronic alcohol exposure on transcriptome in brain. The open field test and novel object recognition test were used to assess the changes of anxiety level, locomotive function, and short-term memory induced by alcohol. RNA-seq analysis revealed that chronic alcohol exposure caused significant change in the brain transcriptome, especially in prefrontal cortex. RESULTS: The gene dysregulation caused by chronic alcohol exposure includes pathways related to mitochondrial energy metabolism (such as oxidative phosphorylation) and multiple neurodegenerative diseases (such as AD and PD). Furthermore, the pathway and network analyses suggest that the genes involved in mitochondrial energy metabolism, ubiquitin-proteasome system, Wnt signaling pathway, and microtubules may attribute to the neurotoxicity and neurodegeneration caused by chronic alcohol consumption. Additionally, locomotive function was also significantly impaired. CONCLUSION: This work provides gene transcriptional profile data for future research on alcohol-induced neurodegenerative diseases, especially AD and PD.
Subject(s)
Alzheimer Disease , Parkinson Disease , Alzheimer Disease/metabolism , Animals , Brain , Ethanol/metabolism , Ethanol/toxicity , Gene Expression , Humans , Male , Mice , Mice, Inbred C57BL , Parkinson Disease/metabolism , Prefrontal Cortex/metabolismABSTRACT
Neuroinflammation is a leading cause of secondary neuronal injury in neonatal hypoxic-ischemic encephalopathy (HIE). Regulation of neuroinflammation may be beneficial for treatment of HIE and its secondary complications. Gallic acid (GA) has been shown to have anti-inflammatory and antioxidant effects. In this report we found that oxygen-glucose deprivation and/reoxygenation (OGD/R)-induced cell death, and the generation of excessive reactive oxygen species (ROS) and inflammatory cytokines by microglia were inhibited by GA treatment. Furthermore, GA treatment reduced neuroinflammation and neuronal loss, and alleviated motor and cognitive impairments in rats with hypoxic-ischemic brain damage (HIBD). Together, our results reveal that GA is an effective regulator of neuroinflammation and has potential as a pharmaceutical intervention for HIE therapy.
ABSTRACT
BACKGROUND: Interleukin-10 (IL-10) is a classic anti-inflammatory cytokine that exerts its effects via the receptor complexes IL-10RA and IL-10RB. Loss of IL-10RB results in many diseases. Moreover, IL-10RB is closely associated with neuronal survival and synaptic formation. However, the regulation of IL-10RB gene expression remains elusive. OBJECTIVE: To investigate whether the expression of IL-10RB gene is increased in brain of Alzheimer's disease (AD) and its transcriptional regulation. METHODS: We examined the gene expression of AD patient brain from public database and detected the protein expression of AD model mouse brain by western blot. We constructed a variety of reporter gene plasmids with different lengths or mutation sites, tested the promoter activity and defined the functional region of the promoter with the luciferase reporter assay. The protein-DNA binding between transcription factors and the promoter was analyzed using chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA). RESULTS: We found that the IL-10RB is elevated in the brain of AD patient and AD model mice. The minimal promoter of the IL-10RB gene is located in the -90 to +51 bp region (relative to the transcriptional start site) and is sufficient for high-level expression of the IL-10RB gene. Transcription factors Sp8 and Sp9 bind to the IL-10RB promoter in vitro. The overexpression or knockdown of Sp8 and Sp9 affected the IL-10RB promoter activity and its gene expression. CONCLUSION: Our study functionally characterized the promoter of the IL-10RB gene and demonstrated that Sp8 and Sp9 regulated its expression.