RESUMO
Induction of eomesodermin-positive CD4+ T cells (Eomes+ T helper [Th] cells) has recently been correlated with the transition from an acute stage to a later stage of experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis. Moreover, these cells' pathogenic role has been experimentally proven in EAE. While exploring how the pathogenic Eomes+ Th cells are generated during the course of EAE, we unexpectedly found that B cells and MHC class II+ myeloid cells isolated from the late EAE lesions strikingly up-regulated the expression of prolactin (PRL). We demonstrate that such PRL-producing cells have a unique potential to induce Eomes+ Th cells from naïve T cells ex vivo, and that anti-MHC class II antibody could block this process. Furthermore, PRL levels in the cerebrospinal fluid were significantly increased in the late phase of EAE, and blocking the production of PRL by bromocriptine or Zbtb20-specific siRNA significantly reduced the numbers of Eomes+ Th cells in the central nervous system (CNS) and ameliorated clinical signs in the later phase of EAE. The PRL dependency of Eomes+ Th cells was confirmed in a series of in vitro and ex vivo experiments. Collectively, these results indicate that extrapituitary PRL plays a crucial role in the CNS inflammation mediated by pathogenic Eomes+ Th cells. Cellular interactions involving PRL-producing immune cells could be considered as a therapeutic target for the prevention of chronic neuroinflammation.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Sistema Nervoso Central/imunologia , Inflamação/imunologia , Prolactina/imunologia , Proteínas com Domínio T/imunologia , Animais , Linfócitos B/imunologia , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/imunologia , Células Mieloides/imunologiaRESUMO
Previous studies have established the antitumor activity of curcumin, a major component of turmeric. Increasing evidence indicates that curcumin induces autophagy, the activation of mitogen-activated protein kinase (MAPK) intracellular signaling pathways, and reactive oxygen species (ROS)-mediated cell death. The c-Jun NH2-terminal kinase (JNK)-associated leucine zipper protein (JLP), a scaffold protein for MAPK signaling pathways, has been identified as a candidate biomarker for cancer. In this study, we explored the role of JLP in curcumin-induced cancer cell death. We found that JLP knockdown (KD) increases cell death and intracellular ROS levels. Furthermore, JLP KD impaired lysosomal accumulation around perinuclear regions, which led to the inhibition of autophagosome-lysosome fusion, and attenuated p38 MAPK activation in curcumin-treated cells. The decreases in cell viability and p38 MAPK activation were reversed by expressing wild-type JLP but not a JLP mutant lacking the p38 MAPK-binding domain. In addition, the inactivation of a key gene involved in autophagy increased sensitivity to curcumin-induced cell death. Together, these results suggest that JLP mediates the induction of autophagy by regulating lysosome positioning and p38 MAPK signaling, indicating an overall protective role in curcumin-induced ROS-mediated cancer cell death.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/farmacologia , Curcumina/farmacologia , Neoplasias/tratamento farmacológico , Autofagia/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
Acquired drug resistance is a major problem in chemotherapy, and understanding of the mechanism, by which naïve cells defend themselves from drugs when the cells exposed to the drugs for the first time, may provide a solution of the problem. Gefitinib is an epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor, and used as an anticancer drug; however, gefitinib treatment may sometimes lead cancer cells gradually into a gefitinib-tolerance. Here we describe that human adenocarcinoma PC-9 cells even under the presence of gefitinib were able to survive by activating another signaling pathway involving fibroblast growth factor receptor (FGFR) and its signaling molecule, FGF2; and further suggest that the FGF2 for initiating the pathway might be supplied from neighboring cells which were killed by gefitinib, i.e., the survival might be founded on neighbors' sacrifice in an early stage of gefitinib treatment. Our findings suggested that whether cells had a chance to encounter to survival factors such as FGF2 soon after gefitinib treatment might be an important crossroads for the cells for survival and for gaining a gefitinib tolerance.
Assuntos
Adenocarcinoma/patologia , Morte Celular , Quinazolinas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Gefitinibe , Perfilação da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais , Resultado do TratamentoRESUMO
Dysregulation of cell proliferation and the cell cycle are associated with various diseases, such as cancer. Cyclin-dependent kinases (CDKs) play central roles in cell proliferation and the cell cycle. Ubiquitin C-terminal hydrolase L1 (UCH-L1) is expressed in a restricted range of tissues, including the brain and numerous types of cancer. However, the molecular functions of UCH-L1 remain elusive. In this study, we found that UCH-L1 physically interacts with CDK1, CDK4, and CDK5, enhancing their kinase activity. Using several mutants of UCH-L1, we showed that this enhancement is dependent upon interaction levels between UCH-L1 and CDKs but is independent of the known ubiquitin-related functions of UCH-L1. Gain- and loss-of-function studies revealed that UCH-L1 enhances proliferation of multiple cell types, including human cancer cells. Inhibition of the interaction between UCH-L1 and cell cycle-associated CDK resulted in the abolishment of UCH-L1-induced enhancement of cell proliferation. RNA interference of UCH-L1 reduced the growth of human xenograft tumors in mice. We concluded that UCH-L1 is a novel regulator of the kinase activities of CDKs. We believe that our findings from this study will significantly contribute to our understanding of cell cycle-associated diseases.
Assuntos
Proteína Quinase CDC2/metabolismo , Proliferação de Células , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 5 Dependente de Ciclina/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/enzimologia , Ubiquitina Tiolesterase/metabolismo , Animais , Proteína Quinase CDC2/genética , Células COS , Chlorocebus aethiops , Quinase 4 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/genética , Células HeLa , Humanos , Camundongos , Mutação , Células NIH 3T3 , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Neoplasias/genética , Neoplasias/patologia , Transplante Heterólogo , Ubiquitina Tiolesterase/genéticaRESUMO
Allele-specific silencing by RNA interference (ASP-RNAi) is an atypical RNAi that is capable of discriminating target alleles from non-target alleles, and may be therapeutically useful for specific inhibition of disease-causing alleles without affecting their corresponding normal alleles. However, it is difficult to design and select small interfering RNA (siRNAs) that confer ASP-RNAi. A major problem is that there are few appropriate measures in determining optimal allele-specific siRNAs. Here we show two novel formulas for calculating a new measure of allele-discrimination, named "ASP-score". The formulas and ASP-score allow for an unbiased determination of optimal siRNAs, and may contribute to characterizing such allele-specific siRNAs.
Assuntos
Alelos , Inativação Gênica/fisiologia , Interferência de RNA/fisiologia , RNA Interferente Pequeno/genética , Sequência de Bases , Engenharia Genética/métodos , Células HeLa , Humanos , Luciferases , Modelos Genéticos , Dados de Sequência MolecularRESUMO
Fibrodysplasia ossificans progressiva (FOP) is a rare congenital disorder characterized by progressive ossification of soft tissues. FOP is caused by mutations in activin receptor-like kinase 2 (ALK2) that cause its constitutive activation and result in dysregulation of BMP signaling. Here, we show that generation of induced pluripotent stem cells (iPSCs) from FOP-derived skin fibroblasts is repressed because of incomplete reprogramming and inhibition of iPSC maintenance. This repression was mostly overcome by specific suppression of ALK2 expression and treatment with an ALK2 inhibitor, indicating that the inhibition of iPSC generation and maintenance observed in FOP-derived skin fibroblasts results from constitutive activation of ALK2. Using this system, we identified an ALK2 inhibitor as a potential candidate for future drug development. This study highlights the potential of the inhibited production and maintenance of iPSCs seen in diseases as a useful phenotype not only for studying the molecular mechanisms underlying iPS reprogramming but also for identifying drug candidates for future therapies.
Assuntos
Receptores de Ativinas Tipo I/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Miosite Ossificante/patologia , Receptores de Ativinas Tipo I/antagonistas & inibidores , Receptores de Ativinas Tipo I/metabolismo , Animais , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Técnicas de Cocultura , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/fisiologia , Camundongos , Mutação de Sentido Incorreto , Miosite Ossificante/genética , Fenótipo , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais , Pele/patologia , TranscriptomaRESUMO
Bone morphogenetic proteins (BMPs) inhibit myogenesis and induce osteoblastic differentiation in myoblasts. They also induce the transcription of several common genes, such as Id1, Id2 and Id3, in various cell types. We have reported that a GC-rich element in the Id1 gene functions as a BMP-responsive element (BRE) that is regulated by Smads. In this study, we analyzed and identified BREs in the 5'-flanking regions of the mouse Id2 and Id3 genes. The core GGCGCC sequence was conserved among the BREs in the Id1, Id2 and Id3 genes and was essential for the response to BMP signaling via Smads. We found a novel BRE on mouse chromosome 13 at position 47,723,740-47,723,768 by searching for conserved sequences containing the Id1 BRE. This potential BRE was found in the 5'-flanking region of a novel gene that produces a non-coding transcript, termed BMP-inducible transcript-1 (BIT-1), and this element regulated the expression of this gene in response to BMP signaling. We found that BIT-1 is expressed in BMP target tissues such as the testis, brain, kidney and cartilage. These findings suggest that the transcriptional induction of the Ids, BIT-1 and additional novel genes containing the conserved BRE sequence may play an important role in the regulation of the differentiation and/or function of target cells in response to BMPs.
Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas Inibidoras de Diferenciação/biossíntese , Proteínas Musculares/metabolismo , Mioblastos/metabolismo , RNA não Traduzido/metabolismo , Elementos de Resposta/fisiologia , Transdução de Sinais/fisiologia , Animais , Proteínas Morfogenéticas Ósseas/genética , Linhagem Celular , Cromossomos de Mamíferos/genética , Cromossomos de Mamíferos/metabolismo , Camundongos , Proteínas Musculares/genética , Especificidade de Órgãos , RNA não Traduzido/genéticaRESUMO
Nucleotide variations, including SNPs, in the coding regions of disease genes are important targets for RNAi treatment, which is a promising medical treatment for intractable diseases such as triplet repeat diseases. However, the identification of such nucleotide variations and the design of siRNAs conferring disease allele-specific RNAi are quite difficult. In this study we developed a pull-down method to rapidly identify coding SNP (cSNP) haplotypes of triple repeat, disease-causing alleles, and we demonstrated disease allele-specific RNAi that targeted cSNP sites in mutant Huntingtin alleles, each of which possessed a different cSNP haplotype. Therefore, the methods presented here allow for allele-specific RNAi knockdown against disease-causing alleles by using siRNAs specific to disease-linked cSNP haplotypes, and advanced progress toward tailor-made RNAi treatments for triplet repeat diseases.
Assuntos
Alelos , Técnicas de Silenciamento de Genes , Predisposição Genética para Doença , Interferência de RNA , Repetições de Trinucleotídeos , Células HEK293 , Haplótipos , Células HeLa , Humanos , Proteína Huntingtina , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , RNA Interferente Pequeno/genéticaRESUMO
The ubiquitin-proteasome system (UPS) is a proteolytic pathway that is essential for life maintenance and vital functions, and its disruption causes serious impairments, e.g., disease development. Thus, the UPS is properly regulated. Here we show novel UPS-related factors: the fragile X mental retardation 1 (FMR1) and Fmr1 autosomal homolog 1 (FXR1) proteins and discs large MAGUK scaffold protein 4 (Dlg4) mRNA, which are associated with Fragile X syndrome, are involved in UPS activity. Fmr1-, Fxr1- and Dlg4-knockdown and Fmr1- and Fxr1-knockdown resulted in increased ubiquitination and proteasome activity, respectively. FXR1 protein was further confirmed to be associated with proteasomes, and Dlg4 mRNA itself was found to be involved in the UPS. Knockdown of these genes also affected neurite outgrowth. These findings provide new insights into the regulatory mechanism of the UPS and into the interpretation of the pathogenesis of diseases in which these genes are involved as UPS-related factors.
Assuntos
Síndrome do Cromossomo X Frágil , Humanos , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/metabolismo , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo , Proteínas de Ligação a RNA/genética , Proteína 4 Homóloga a Disks-Large/metabolismoRESUMO
In addition to disease-associated microglia (DAM), microglia with MHC-II and/or IFN-I signatures may form additional pathogenic subsets that are relevant to neurodegeneration. However, the significance of such MHC-II and IFN-I signatures remains elusive. We demonstrate here that these microglial subsets play intrinsic roles in orchestrating neurotoxic properties of neurotoxic Eomes+ Th cells under the neurodegeneration-associated phase of experimental autoimmune encephalomyelitis (EAE) that corresponds to progressive multiple sclerosis (MS). Microglia acquire IFN-signature after sensing ectopically expressed long interspersed nuclear element-1 (L1) gene. Furthermore, ORF1, an L1-encoded protein aberrantly expressed in the diseased central nervous system (CNS), stimulated Eomes+ Th cells after Trem2-dependent ingestion and presentation in MHC-II context by microglia. Interestingly, administration of an L1 inhibitor significantly ameliorated neurodegenerative symptoms of EAE concomitant with reduced accumulation of Eomes+ Th cells in the CNS. Collectively, our data highlight a critical contribution of new microglia subsets as a neuroinflammatory hub in immune-mediated neurodegeneration.
Assuntos
Encefalomielite Autoimune Experimental , Microglia , Animais , Microglia/metabolismo , Encefalomielite Autoimune Experimental/patologia , Sistema Nervoso Central/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismoRESUMO
Small RNAs derived from repetitive sequences appear to play essential roles in mammalian gametogenesis and early development. In this study we focused on the short interspersed nucleotide element B1 (SINE/B1) small RNAs, which were zygotically expressed in pre-implantation mouse embryos; and we investigated whether the SINE/B1 small RNAs played an active role in gene silencing during early mouse development. The results indicated that the level of silencing activity involving the SINE/B1 small RNAs as mediators was significantly reduced in Dicer-knockdown mouse embryos. In addition, when the SINE/B1 small RNAs were mapped to a full-length SINE/B1 sequence, phase-distribution of the small RNAs appeared, suggesting possible enzymatic involvement. Therefore, our present study suggested that the zygotically expressed SINE/B1 small RNAs in pre-implantation mouse embryos contain active small RNAs, which were presumably processed by Dicer and involved in gene silencing.
Assuntos
Blastocisto/metabolismo , Desenvolvimento Embrionário/genética , Gametogênese/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Pequeno RNA não Traduzido/metabolismo , Animais , Blastocisto/fisiologia , RNA Helicases DEAD-box/genética , Eletroporação , Técnicas de Silenciamento de Genes , Sequenciamento de Nucleotídeos em Larga Escala , Camundongos , Anotação de Sequência Molecular , Oligonucleotídeos/genética , Pequeno RNA não Traduzido/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonuclease III/genética , Elementos Nucleotídeos Curtos e Dispersos/genéticaRESUMO
Recent studies showed that small interfering RNAs (siRNAs) and Piwi-interacting RNA (piRNA) in mammalian germ cells play important roles in retrotransposon silencing and gametogenesis. However, subsequent contribution of those small RNAs to early mammalian development remains poorly understood. We investigated the expression profiles of small RNAs in mouse metaphase II oocytes, 8-16-cell stage embryos, blastocysts and the pluripotent inner cell mass (ICM) using high-throughput pyrosequencing. Here, we show that during pre-implantation development a major small RNA class changes from retrotransposon-derived small RNAs containing siRNAs and piRNAs to zygotically synthesized microRNAs (miRNAs). Some siRNAs and piRNAs are transiently upregulated and directed against specific retrotransposon classes. We also identified miRNAs expression profiles characteristic of the ICM and trophectoderm (TE) cells. Taken together, our current study reveals a major reprogramming of functional small RNAs during early mouse development from oocyte to blastocyst.
Assuntos
Blastocisto/metabolismo , Desenvolvimento Embrionário/genética , MicroRNAs/metabolismo , RNA Interferente Pequeno/metabolismo , Animais , Massa Celular Interna do Blastocisto/metabolismo , Células Cultivadas , RNA Helicases DEAD-box/antagonistas & inibidores , Endorribonucleases/antagonistas & inibidores , Feminino , Camundongos , Camundongos Endogâmicos ICR , Oócitos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Retroelementos , Ribonuclease IIIRESUMO
Neurodegeneration is a process involving both cell autonomous and non-cell autonomous neuron loss, followed by a collapse of neural networks, but its pathogenesis is poorly understood. We have previously demonstrated that Eomes-positive helper T (Eomes + Th) cells recognizing LINE-1(L1)-derived prototypic antigen ORF1 mediate neurotoxicity associated with the neurodegenerative pathology of experimental autoimmune encephalomyelitis (EAE). Here, we show that Eomes + Th cells accumulate in the CNS of mouse models of authentic neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) and Alzheimer's disease (AD), and secrete the neurotoxic granzyme B after encounter with ORF1 antigen. Multimodal derepression of neuronal L1 transcription is observed in EAE and ALS/AD models during neurodegeneration in active and cell cycle-mediated manner, respectively. These data suggest that the adventitious concurrence of immune-mediated neurodegenerative traits by Eomes + Th cells and ectopic expression of L1-derived antigen(s) in the inflamed CNS may materialize a communal and previously unappreciated pathogenesis of neurodegeneration.
RESUMO
BACKGROUND: Cachexia is a life-threatening condition observed in several pathologies, such as cancer or chronic diseases. Interleukin 10 (Il10) gene transfer is known to improve cachexia by downregulating Il6. Here, we used an IL10-knockout mouse model to simulate cachexia and investigate the effects of eggshell membrane (ESM), a resistant protein, on general pre-cachexia symptoms, which is particularly important for the development of cachexia therapeutics. METHODS: Five-week-old male C57BL6/J mice were fed an AIN-93G powdered diet (WT), and 5-week-old male B6.129P2-Il10 < tm1Cgn>/J (IL10-/- ) mice were fed either the AIN-93G diet (KO) or an 8% ESM-containing diet (KOE) for 28 weeks. The tissue weight and levels of anaemia-, blood glucose-, lipid metabolism-, and muscular and colonic inflammation-related biochemical markers were measured. Transcriptomic analysis on liver and colon mucus and proteomic analysis on skeletal muscle were performed. Ingenuity Pathway Analysis was used to identify molecular pathways and networks. Caecal short-chain fatty acids (SCFAs) were identified using HPLC, and caecal bacteria DNA were subjected to metagenomic analysis. Flow cytometry analysis was performed to measure the CD4+ IL17+ T cells in mesenteric lymph nodes. RESULTS: The body weight, weight of gastrocnemius muscle and fat tissues, colon weight/length ratio, plasma HDL and NEFA, muscular PECAM-1 levels (P < 0.01), plasma glucose and colonic mucosal myeloperoxidase activity (P < 0.05) and T helper (Th) 17 cell abundance (P = 0.071) were improved in KOE mice over KO mice. Proteomic analysis indicated the protective role of ESM in muscle weakness and maintenance of muscle formation (>1.5-fold). Transcriptomic analysis revealed that ESM supplementation suppressed the LPS/IL1-mediated inhibition of RXR function pathway in the liver and downregulated the colonic mucosal expression of chemokines and Th cell differentiation-related markers (P < 0.01) by suppressing the upstream BATF pathway. Analysis of the intestinal microenvironment revealed that ESM supplementation ameliorated the microbial alpha diversity and the abundance of microbiota associated with the degree of inflammation (P < 0.05) and increased the level of total organic acids, particularly of SCFAs such as butyrate (2.3-fold), which could inhibit Th1 and Th17 production. CONCLUSIONS: ESM supplementation ameliorated the chief symptoms of cachexia, including anorexia, lean fat tissue mass, skeletal muscle wasting and reduced physical function. ESM also improved colon and skeletal muscle inflammation, lipid metabolism and microbial dysbiosis. These results along with the suppressed differentiation of Th cells could be associated with the beneficial intestinal microenvironment and, subsequently, attenuation of pre-cachexia. Our findings provide insights into the potential of ESM in complementary interventions for pre-cachexia prevention.
Assuntos
Caquexia , Casca de Ovo , Microbioma Gastrointestinal , Linfócitos T Auxiliares-Indutores , Animais , Caquexia/prevenção & controle , Diferenciação Celular , Dieta , Inflamação , Interleucina-10 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteômica , Linfócitos T Auxiliares-Indutores/citologiaRESUMO
ARX (the aristaless-related homeobox gene) is a transcription factor that participates in the development of GABAergic and cholinergic neurons in the forebrain. Many ARX mutations have been identified in X-linked lissencephaly and mental retardation with epilepsy, and thus ARX is considered to be a causal gene for the two syndromes although the neurobiological functions of each mutation remain unclear. We attempted to elucidate the causal relationships between individual ARX mutations and disease phenotypes by generating a series of mutant mice. We generated three types of mice with knocked-in ARX mutations associated with X-linked lissencephaly (P353R) and mental retardation [P353L and 333ins(GCG)7]. Mice with the P355R mutation (equivalent to the human 353 position) that died after birth were significantly different in Arx transcript/protein amounts, GABAergic and cholinergic neuronal development, brain morphology and lifespan from mice with P355L and 330ins(GCG)7 but considerably similar to Arx-deficient mice with truncated ARX mutation in lissencephaly. Mice with the 330ins(GCG)7 mutation showed severe seizures and impaired learning performance, whereas mice with the P355L mutation exhibited mild seizures and only slightly impaired learning performance. Both types of mutant mice exhibited the mutation-specific lesser presence of GABAergic and cholinergic neurons in the striatum, medial septum and ventral forebrain nuclei when compared with wild-type mice. Present findings that reveal a causal relationship between ARX mutations and the pleiotropic phenotype in mice, suggest that the ARX-related syndrome, including lissencephaly or mental retardation, is caused by only the concerned ARX mutations without the involvement of other genetic factors.
Assuntos
Epilepsia/genética , Proteínas de Homeodomínio/genética , Deficiência Intelectual/genética , Lisencefalia/genética , Mutação , Fatores de Transcrição/genética , Animais , Modelos Animais de Doenças , Proteína Duplacortina , Epilepsia/metabolismo , Feminino , Proteínas de Homeodomínio/metabolismo , Humanos , Deficiência Intelectual/metabolismo , Lisencefalia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Fatores de Transcrição/metabolismoRESUMO
Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) mediated by Th17 and Th1 cells. DNA microarray analysis previously showed that NR4A2, an orphan nuclear receptor, is strongly up-regulated in the peripheral blood T cells of MS. Here, we report that NR4A2 plays a pivotal role for mediating cytokine production from pathogenic T cells. In experimental autoimmune encephalomyelitis (EAE), an animal model of MS, NR4A2, was selectively up-regulated in the T cells isolated from the CNS. Strikingly, a forced expression of NR4A2 augmented promoter activities of IL-17 and IFN-gamma genes, leading to an excessive production of these cytokines. Conversely, treatment with siRNA for NR4A2, resulted in a significant reduction in the production of IL-17 and IFN-gamma. Furthermore, treatment with NR4A2 siRNA reduced the ability of encephalitogenic T cells to transfer EAE in recipient mice. Thus, NR4A2 is an essential transcription factor for triggering the inflammatory cascade of MS/EAE and may serve as a therapeutic target.
Assuntos
Citocinas/biossíntese , Proteínas de Ligação a DNA/metabolismo , Encefalomielite Autoimune Experimental/imunologia , Esclerose Múltipla/imunologia , Linfócitos T/imunologia , Fatores de Transcrição/metabolismo , Animais , Encéfalo/imunologia , Citocinas/genética , Proteínas de Ligação a DNA/genética , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/terapia , Feminino , Inativação Gênica , Interferon gama/biossíntese , Interferon gama/genética , Interleucina-17/biossíntese , Interleucina-17/genética , Camundongos , Esclerose Múltipla/genética , Esclerose Múltipla/terapia , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares , RNA Interferente Pequeno/genética , Retroviridae/genética , Fatores de Transcrição/genética , Transdução Genética , Regulação para CimaRESUMO
Multiple sclerosis (MS) is an autoimmune neurodegenerative disease of the central nervous system (CNS) characterized by multiple demyelinating lesions in the spinal cord and brain. Neuronal disruption caused by myelin loss or demyelination, which may accompany axonal changes, leads to multiple neurological symptoms. They may transiently appear for weeks during periods of disease worsening (relapse) in relapsing-remitting form of MS (RRMS). Although a number of genetic, metabolic and environmental factors influencing the development of MS have been identified, the precise mechanisms involved in the CNS tissue damage in MS are still poorly understood. Recent studies have revealed a significant role of circulating extracellular vesicles (EVs) in many diseases. EVs are known to serve as a cellular communication tool between two cell types either in close proximity or in different parts of the body. During the recent development in understanding of the pathogenesis of MS, studies have revealed the possible role of EVs in MS. Furthermore, circulating EVs can be used as a biomarker for monitoring disease progression and activity of MS, and they can also be therapeutic reagents or targets of therapy. In this review we overview and discuss in detail about generation of EVs and their diversified roles in MS.
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Parabiosis experiments suggest that molecular factors related to rejuvenation and aging circulate in the blood. Here, we show that miR-199-3p, which circulates in the blood as a cell-free miRNA, is significantly decreased in the blood of aged mice compared to young mice; and miR-199-3p has the ability to enhance myogenic differentiation and muscle regeneration. Administration of miR-199 mimics, which supply miR-199-3p, to aged mice resulted in muscle fiber hypertrophy and delayed loss of muscle strength. Systemic administration of miR-199 mimics to mdx mice, a well-known animal model of Duchenne muscular dystrophy (DMD), markedly improved the muscle strength of mice. Taken together, cell-free miR-199-3p in the blood may have an anti-aging effect such as a hypertrophic effect in aged muscle fibers and could have potential as a novel RNA therapeutic for DMD as well as age-related diseases. The findings provide us with new insights into blood-circulating miRNAs as age-related molecules.
Assuntos
Envelhecimento/fisiologia , MicroRNAs/metabolismo , Músculo Esquelético/fisiopatologia , Distrofia Muscular de Duchenne/genética , Regeneração/fisiologia , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Distrofia Muscular de Duchenne/fisiopatologia , Regeneração/genéticaRESUMO
Curcumin, a major component of turmeric, is known to exhibit multiple biological functions including antitumor activity. We previously reported that the mitogen-activated protein kinase (MAPK) scaffold protein c-Jun NH2-terminal kinase (JNK)-associated leucine zipper protein (JLP) reduces curcumin-induced cell death by modulating p38 MAPK and autophagy through the regulation of lysosome positioning. In this study, we investigated the role of JNK/stress-activated protein kinase-associated protein 1 (JSAP1), a JLP family member, in curcumin-induced stress, and found that JSAP1 also attenuates curcumin-induced cell death. However, JSAP1 knockout showed no or little effect on the activation of JNK and p38 MAPKs in response to curcumin. In addition, small molecule inhibitors of JNK and p38 MAPKs did not increase curcumin-induced cell death. Furthermore, JSAP1 depletion did not impair lysosome positioning and autophagosome-lysosome fusion. Instead, we noticed substantial autolysosome accumulation accompanied by an inefficient autophagic flux in JSAP1 knockout cells. Taken together, these results indicate that JSAP1 is involved in curcumin-induced cell death differently from JLP, and may suggest that JSAP1 plays a role in autophagosome degradation and its dysfunction results in enhanced cell death. The findings of this study may contribute to the development of novel therapeutic approaches using curcumin for cancer.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/farmacologia , Antineoplásicos/farmacologia , Curcumina/farmacologia , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Proteínas do Tecido Nervoso/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/efeitos adversos , Autofagia/efeitos dos fármacos , Autofagia/genética , Técnicas de Cultura de Células , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Curcumina/efeitos adversos , Desenvolvimento de Medicamentos/métodos , Humanos , Zíper de Leucina/genética , Lisossomos/efeitos dos fármacos , Lisossomos/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias/tratamento farmacológico , Proteínas do Tecido Nervoso/metabolismo , Substâncias Protetoras , Espécies Reativas de Oxigênio/metabolismoRESUMO
SCOPE: We previously demonstrated that protein restriction in utero induced salt-sensitive hypertension and changed renal levels of angiotensin type 2 receptor (AT2R) in Stroke-Prone Spontaneously Hypertensive Rat (SHRSP). Here, we investigated if this characteristic alteration of AT2R is related to AT2R DNA methylation profiles. METHODS AND RESULTS: First, we examined the relation between AT2R DNA methylation and its promoter activity in vitro. Luciferase assays revealed a negative correlation between these two variables. Next, we fed SHRSP dams and grand-dams a control 20% casein diet or a 9% casein diet during pregnancy. Adult offspring and grand-offspring were supplied either water or 1% saline solution for 2 weeks. Renal AT2R promoter DNA near the TATA-box was hypomethylated, mRNA expression was suppressed, and protein expression tended to be higher, in adult offspring of mothers fed a low casein diet. Moreover, adult grand-offspring exhibited high blood pressure after salt loading, along with suppressed transcription of AT2R mRNA and elevated translated protein. CONCLUSIONS: Under a fetal environment of protein restriction, the increase in protein expression due to hypomethylation of the AT2R promoter region occurs as a response to increased salt sensitivity, and controlling this mechanism may be important for the prevention of hypertension.