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1.
Toxicol Res (Camb) ; 9(5): 622-631, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33178422

RESUMO

Diethylhexyl phthalate (DEHP) is known as a persistent environmental pollutant. However, the possible effects of DEHP on human neural tube defects (NTDs) remain elusive. We set out to investigate the exposure of DEHP in human and explore the association of DEHP and NTDs. The level of DEHP in maternal urine was measured and analyzed by GC-MS. To further validate the results in human NTDs, chick embryos were used as animal models. Viability, reactive oxygen species (ROS) level, oxidative stress indicators and apoptosis were detected in DEHP-treated chick embryos. Our research revealed that the detection ratio of positive DEHP and its metabolites in maternal urine were observed dramatically higher in NTDs population than that in normal controls (P < 0.01, P < 0.05, respectively). Moreover, DEHP treatment (10-6 M) led to developmental toxicity in chick embryos via accelerating oxidative stress response and cell apoptosis, and changing the level of oxidative stress-related indicators. Moreover, high dose choline (100 µg/µl) could partially restrain the toxicity effects induced by DEHP. Our data collectively imply that the incidence of NTDs may closely associate with DEHP exposure, which disturbs the development of neural tubes by enhancing oxidative stress.

2.
Toxicol Res (Camb) ; 9(3): 222-229, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32670553

RESUMO

Benzyl butyl phthalate (BBP) is a persistent environmental pollutant. BBP exposure and the possible effects on human neural tube defects (NTDs) remain elusive. In this study, we found that the detection ratio of positive BBP and its metabolites in maternal urine was obviously higher in NTDs' population than that in normal controls by GC-MS (P < 0.01, P < 0.05, respectively). Animal experiments showed that BBP treatment induced developmental toxicity in chick embryo by enhancing the levels of oxidative stress and cell apoptosis (P < 0.01). More interestingly, the supplement of high-dose choline (CHO, 10 5  µg/mL) could partially restore the teratogenic effects of BBP by inhibiting the occurrence of oxidative stress. Our data collectively suggest that BBP exposure may disturb neural tube development by strengthening oxidative stress. CHO can partially restore the toxicity effects of BBP. This study may provide new insight for NTD prevention.

3.
BMC Med Genet ; 20(1): 182, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727123

RESUMO

BACKGROUND: Majeed syndrome is a rare, autosomal recessive autoinflammatory disorder first described in 1989. The syndrome starts during infancy with recurrent relapses of osteomyelitis typically associated with fever, congenital dyserythropoietic anemia (CDA), and often neutrophilic dermatosis. Mutations in the LPIN2 gene located on the short arm of chromosome 18 have been identified as being responsible for Majeed syndrome. CASE PRESENTATION: We report an 8-month-old boy, who presented with recurrent fever, mild to moderate anemia, and severe neutropenia. Erythrocyte sedimentation rate and C-reactive protein were elevated. Molecular testing identified a paternal splicing donor site variant c.2327 + 1G > C and a maternal frameshift variant c.1691_1694delGAGA (Arg564Lysfs*3) in LPIN2. CONCLUSIONS: Only a few cases with LPIN2 mutation have been reported, mainly in the Middle East with homozygous variants. Our patient exhibited a mild clinical phenotype and severe neutropenia, different from previous reports.


Assuntos
Anemia Diseritropoética Congênita/genética , Febre/complicações , Síndromes de Imunodeficiência/genética , Mutação , Neutropenia/complicações , Proteínas Nucleares/genética , Osteomielite/genética , Anemia Diseritropoética Congênita/complicações , Feminino , Humanos , Síndromes de Imunodeficiência/complicações , Lactente , Masculino , Osteomielite/complicações , Linhagem , Recidiva , Índice de Gravidade de Doença
4.
Autophagy ; 12(7): 1168-79, 2016 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-27171858

RESUMO

Searching for new regulators of autophagy involved in selective dopaminergic (DA) neuron loss is a hallmark in the pathogenesis of Parkinson disease (PD). We here report that an endoplasmic reticulum (ER)-associated transmembrane protein SLC35D3 is selectively expressed in subsets of midbrain DA neurons in about 10% TH (tyrosine hydroxylase)-positive neurons in the substantia nigra pars compacta (SNc) and in about 22% TH-positive neurons in the ventral tegmental area (VTA). Loss of SLC35D3 in ros (roswell mutant) mice showed a reduction of 11.9% DA neurons in the SNc and 15.5% DA neuron loss in the VTA with impaired autophagy. We determined that SLC35D3 enhanced the formation of the BECN1-ATG14-PIK3C3 complex to induce autophagy. These results suggest that SLC35D3 is a new regulator of tissue-specific autophagy and plays an important role in the increased autophagic activity required for the survival of subsets of DA neurons.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Autofagia/fisiologia , Proteína Beclina-1/metabolismo , Neurônios Dopaminérgicos/metabolismo , Mesencéfalo/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Classe III de Fosfatidilinositol 3-Quinases , Dopamina/metabolismo , Camundongos Knockout , Degeneração Neural/patologia , Tirosina 3-Mono-Oxigenase/metabolismo , Área Tegmentar Ventral/metabolismo
5.
PLoS Genet ; 10(2): e1004124, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24550737

RESUMO

Obesity is one of the largest health problems facing the world today. Although twin and family studies suggest about two-thirds of obesity is caused by genetic factors, only a small fraction of this variance has been unraveled. There are still large numbers of genes to be identified that cause variations in body fatness and the associated diseases encompassed in the metabolic syndrome (MetS). A locus near a sequence tagged site (STS) marker D6S1009 has been linked to obesity or body mass index (BMI). However, its genetic entity is unknown. D6S1009 is located in the intergenic region between SLC35D3 and NHEG1. Here we report that the ros mutant mice harboring a recessive mutation in the Slc35d3 gene show obesity and MetS and reduced membrane dopamine receptor D1 (D1R) with impaired dopamine signaling in striatal neurons. SLC35D3 is localized to both endoplasmic reticulum (ER) and early endosomes and interacts with D1R. In ros striatal D1 neurons, lack of SLC35D3 causes the accumulation of D1R on the ER to impair its ER exit. The MetS phenotype is reversible by the administration of D1R agonist to the ros mutant. In addition, we identified two mutations in the SLC35D3 gene in patients with MetS, which alter the subcellular localization of SLC35D3. Our results suggest that the SLC35D3 gene, close to the D6S1009 locus, is a candidate gene for MetS, which is involved in metabolic control in the central nervous system by regulating dopamine signaling.


Assuntos
Dopamina/genética , Síndrome Metabólica/genética , Proteínas de Transporte de Monossacarídeos/genética , Obesidade/genética , Animais , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Dopamina/metabolismo , Feminino , Humanos , Masculino , Síndrome Metabólica/metabolismo , Síndrome Metabólica/patologia , Camundongos , Proteínas de Transporte de Monossacarídeos/metabolismo , Mutação , Neurônios/metabolismo , Neurônios/patologia , Obesidade/metabolismo , Obesidade/patologia , Receptores de Dopamina D1/genética , Receptores de Dopamina D1/metabolismo , Transdução de Sinais , Córtex Visual/metabolismo , Córtex Visual/patologia
6.
J Cell Physiol ; 228(4): 753-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22949295

RESUMO

Mono (2-ethylhexyl) phthalate (MEHP), an environmental contaminant, is known to cause many serious diseases, especially in reproductive system. However, little is known about the effect of MEHP on preimplantation embryo development. In this study, we found that the development of mouse 2-cell embryo was blocked by 10(-3) M MEHP. A significant increase in the level of reactive oxygen species (ROS) was observed in arrested 2-cell embryo following 10(-3) M MEHP treatment for 24 h. However, antioxidants, catalase (CAT), and superoxide dismutase (SOD), reduced intracellular ROS and protected MEHP-exposed embryos from death but failed to return the arrested embryos. Further experiments demonstrated that the level of apoptosis was not altered in live arrested 2-cell embryo and increased in dead arrested 2-cell embryo after MEHP treatment, which implied that ROS and apoptosis were not related with 2-cell block. During analysis of the indicators of embryonic genome activation (EGA) initiation (Hsc70, MuERV-L, Hsp70.1, eIF-1A, and Zscan4) and maternal-effect genes (OCT4 and SOX2), we found that MEHP treatment could significantly decline Hsc70, MuERV-L mRNA level and SOX2 protein level, and markedly enhance Hsp70.1, eIF-1A, Zscan4 mRNA level, and OCT4 protein level at 2-cell to 4-cell stage. Supplementation of CAT and SOD did not reverse the expression tendency of EGA related genes. Collectively, this study demonstrates for the first time that MEHP-induced 2-cell block is mediated by the failure of EGA onset and maternal-effect genes, not oxidative stress and apoptosis.


Assuntos
Dietilexilftalato/análogos & derivados , Desenvolvimento Embrionário/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/genética , Catalase/genética , Catalase/metabolismo , Dietilexilftalato/farmacologia , Desenvolvimento Embrionário/genética , Fator de Iniciação 1 em Eucariotos/genética , Fator de Iniciação 1 em Eucariotos/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Proteínas de Choque Térmico HSC70/genética , Proteínas de Choque Térmico HSC70/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Oxirredução/efeitos dos fármacos , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
7.
Reprod Fertil Dev ; 25(8): 1174-84, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23231764

RESUMO

Dibutyl phthalate (DBP), a widely used phthalate, is known to cause many serious diseases, especially in the reproductive system. However, little is known about the effects of its metabolite, mono-n-butyl phthalate (MBP), on preimplantation embryo development. In the present study, we found that treatment of embryos with 10⁻³ M MBP impaired developmental competency, whereas exposure to 10⁻4 M MBP delayed the progression of preimplantation embryos to the blastocyst stage. Furthermore, reactive oxygen species (ROS) levels in embryos were significantly increased following treatment with 10⁻³ M MBP. In addition, 10⁻³ M MBP increased apoptosis via the release of cytochrome c, whereas immunofluorescent analysis revealed that exposure of preimplantation embryos to MBP concentration-dependently (10⁻5, 10⁻4 and 10⁻³ M) decreased DNA methylation. Together, the results indicate a possible relationship between MBP exposure and developmental failure in preimplantation embryos.


Assuntos
Apoptose/efeitos dos fármacos , Blastocisto/efeitos dos fármacos , Ectogênese/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Ácidos Ftálicos/toxicidade , Solventes/toxicidade , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Blastômeros/citologia , Blastômeros/efeitos dos fármacos , Blastômeros/metabolismo , Fase de Clivagem do Zigoto/citologia , Fase de Clivagem do Zigoto/efeitos dos fármacos , Fase de Clivagem do Zigoto/metabolismo , Metilação de DNA/efeitos dos fármacos , Técnicas de Cultura Embrionária , Feminino , Fertilização In Vitro , Masculino , Camundongos Endogâmicos ICR , Mórula/citologia , Mórula/efeitos dos fármacos , Mórula/metabolismo , Concentração Osmolar , Plastificantes/toxicidade , Espécies Reativas de Oxigênio/metabolismo
8.
PLoS One ; 7(10): e46173, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23071542

RESUMO

BACKGROUND: MicroRNA-101 (miR-101) expression is negatively associated with tumor growth and blood vessel formation in several solid epithelial cancers. However, the role of miR-101 in human breast cancer remains elusive. RESULTS: MiR-101 was significantly decreased in different subtypes of human breast cancer tissues compared with that in adjacent normal breast tissues (P<0.01). Up-regulation of miR-101 inhibited cell proliferation, migration and invasion, and promoted cell apoptosis in ER alpha-positive and ER alpha-negative breast cancer cells and normal breast cells. Down-regulation of miR-101 displayed opposite effects on cell growth and metastasis. Further investigation revealed a significant inverse correlation between the expression of miR-101 and Stathmin1 (Stmn1), and miR-101 could bind to the 3'-untranslated region (UTR) of Stmn1 to inhibit Stmn1 translation. The inhibition of cell growth and metastasis induced by up-regulation of miR-101 was partially restored by overexpression of Stmn1. Knockdown of Stmn1 attenuates the down-regulation of miR-101-mediated enhancement of cell growth and metastasis. More importantly, in vivo analysis found that Stmn1 mRNA and protein level in different subtypes of human breast cancer tissues, contrary to the down-regulation of miR-101, were significantly elevated. CONCLUSIONS: This study demonstrates that down-regulation of miR-101 in different subtypes of human breast cancer tissues is linked to the increase of cellular proliferation and invasiveness via targeting Stmn1, which highlights novel regulatory mechanism in breast cancer and may provide valuable clues for the future clinical diagnosis of breast cancer.


Assuntos
Neoplasias da Mama/fisiopatologia , Transformação Celular Neoplásica , MicroRNAs/fisiologia , Estatmina/genética , Apoptose , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Divisão Celular , Regulação para Baixo , Feminino , Humanos , Metástase Neoplásica , Regulação para Cima
9.
Cell Physiol Biochem ; 30(2): 382-94, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22739433

RESUMO

BACKGROUND/AIM: The environmental obesogen hypothesis proposes that exposure to endocrine disruptors during developmental "window" contributes to adipogenesis and the development of obesity. Implication of environmental endocrine disruptor such as 4Nonylphenol (4-NP) on adipose tissue development has been poorly investigated. METHODS: 3T3-L1 preadipocytes were incubated with different doses of 4-NP. Six-week-old C57BL/6J male mice received an intraperitoneal injection of vehicle, troglitazone or 4-NP (0.5 mg/kg). Gene expression of adipogenic regulators was analyzed. Pregnant mice were dosed by gavage with vehicle or 4-NP (0.05, 0.25 or 0.5 mg/kg) from day 12 of gestation until day 7 of lactation. The body weight, liver weight, fat mass, and serum lipids and glucose levels were measured in offspring at postnatal day 60. RESULTS: Low concentration of 4-NP induced adipocyte differentiation, glycerol-3-phosphate dehydrogenase activity, and expression of peroxisome proliferator-acivated receptor γ as well as its target genes required for adipogenesis. 4-NP perturbed key regulators of adipogenesis and lipogenic pathway in vivo. Perinatal exposure to 4-NP increased body weight, fat mass, and serum total cholesterol and glucose levels in offspring. CONCLUSIONS: 4-NP may be expected to increase the incidence of obesity and can act as a potential chemical stressor for obesity and obesity-related disorders.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Obesidade/induzido quimicamente , Fenóis/toxicidade , Células 3T3-L1 , Adipogenia/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Glicemia/análise , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Feminino , Glicerolfosfato Desidrogenase/metabolismo , Incidência , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , PPAR gama/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal
10.
Toxicol Appl Pharmacol ; 263(1): 102-10, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22710028

RESUMO

Epidemiology studies indicate that exposure to endocrine disruptors during developmental "window" contributes to adipogenesis and the development of obesity. Implication of endocrine disruptor such as diethylstilbestrol (DES) on adipose tissue development has been poorly investigated. Here we evaluated the effects of DES on adipocyte differentiation in vitro and in vivo, and explored potential mechanism involved in its action. DES induced 3T3-L1 preadipocyte differentiation in a dose-dependent manner, and activated the expression of estrogen receptor (ER) and peroxisome proliferator-acivated receptor (PPAR) γ as well as its target genes required for adipogenesis in vitro. ER mediated the enhancement of DES-induced PPARγ activity. Moreover, DES perturbed key regulators of adipogenesis and lipogenic pathway in vivo. In utero exposure to low dose of DES significantly increased body weight, liver weight and fat mass in female offspring at postnatal day (PND) 60. In addition, serum triglyceride and glucose levels were also significantly elevated. These results suggest that perinatal exposure to DES may be expected to increase the incidence of obesity in a sex-dependent manner and can act as a potential chemical stressor for obesity and obesity-related disorders.


Assuntos
Adipócitos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Dietilestilbestrol/farmacologia , Estrogênios não Esteroides/farmacologia , Obesidade/induzido quimicamente , Células 3T3-L1/efeitos dos fármacos , Animais , Western Blotting , Feminino , Glicerolfosfato Desidrogenase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real
11.
Cell Physiol Biochem ; 29(3-4): 381-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22508046

RESUMO

MiR-206 was involved in a series of cellular activities, such as the growth and development of skeletal muscle and the tumorigenesis. MiR-206 was characterized previously as a differentially expressed gene in sodium arsenite (SA)-induced neural tube defects (NTDs) in chick embryos via miRNA microarray analysis. However, the role of miR-206 in the pathological process of nerve cells remained elusive. In this study we found differential expression of miR-206 in SA-treated chick embryos by Northern blot analysis. Ectopic expression of miR-206 inhibited cell proliferation, and promoted cell apoptosis in U343 and SK-N-SH cell by using MTT, Edu Apollo assay and Flow cytometry analysis. Further investigation revealed that miR-206 can interact with 3'-untranslated region (UTR) of Otx2. MiR-206 mimics down-regulated the endogeneous Otx2 expression, whereas the miR-206 inhibitor obviously up-regulated the expression of Otx2. These findings indicate that overexpression of miR-206 promotes cell apoptosis and low expression of miR-206 inhibits cell apoptosis. Otx2 may play an important role in the process of miR-206-mediated cell apoptosis.


Assuntos
Apoptose , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Fatores de Transcrição Otx/metabolismo , Regiões 3' não Traduzidas , Animais , Arsenitos/farmacologia , Sítios de Ligação , Northern Blotting , Linhagem Celular Tumoral , Sobrevivência Celular , Embrião de Galinha , Citometria de Fluxo , Imunofluorescência , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Humanos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Defeitos do Tubo Neural/induzido quimicamente , Defeitos do Tubo Neural/metabolismo , Defeitos do Tubo Neural/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fatores de Transcrição Otx/genética , Plasmídeos/genética , Plasmídeos/metabolismo , Compostos de Sódio/farmacologia , Transfecção
12.
RNA Biol ; 8(5): 861-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21788734

RESUMO

Although there are plenty of evidence that single-nucleotide polymorphisms (SNPs) that fall within coding sequences of genes are involved in recurrent pregnancy loss (RPL), it is still unknown whether the polymorphisms in microRNAs (miRNAs) are related with RPL. In this study, we established this kind of association by confirming significant differences in genotype distribution of rs41275794 (P= 0.0005) and rs12976445 (P= 0.001) within the pri-miR-125a in 217 Han Chinese patients of RPL compared with 431 controls. Based on this observation, two-locus haplotypes were constructed and the A-T haplotype was found to be associated with an increased risk of RPL (OR=2.84, 95%C.I. 1.98-4.07, P=0.0000000057). Further analysis showed that the levels of pre- and mature- miR-125a were down-regulated in the cells transfected with the A-T haplotype, which was consistent with in vivo detection that the level of mature miR-125a was lower in 30 pregnant women with A-T haplotype than that with G-C haplotype. During in vitro RNA processing assays, we found a similar decrease in the amount of pre-miR-125a and decline in binding capacity of nuclear factors to pri-miR-125a with A-T haplotype. More importantly, the reduction in miR-125a, as a consequence of A-T haplotype, further led to less efficient inhibition of target genes, LIFR and ERBB2, which play important roles in the embryo implantation and decidualization. Thus, our data collectively suggest that two common polymorphisms in pre-miR-125a might contribute to the genetic predisposition to RPL by disrupting the production of miR-125a, which consequently interfered in the expression and function of target genes of miR-125a.


Assuntos
Aborto Habitual/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Aborto Habitual/etnologia , Grupo com Ancestrais do Continente Asiático , Estudos de Casos e Controles , China , Implantação do Embrião/genética , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos , Humanos , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/genética , MicroRNAs/biossíntese , Gravidez , Receptor ErbB-2/genética
13.
Schizophr Res ; 106(2-3): 218-28, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18774265

RESUMO

Schizophrenia (SCZ) is a complex trait with a high heritability. The DTNBP1 gene (encoding dysbindin) is one of the leading susceptible genes of SCZ. This risk gene has been reported to be associated with clinical symptoms such as negative symptoms and cognitive deficits. Although reduction of dysbindin expression in schizophrenic brain tissue has been reported, how this contributes to its symptomatology remains uncertain. The sandy (sdy) mouse, which harbors a spontaneously occurring deletion in the Dtnbp1 gene and expresses no dysbindin protein, provides a unique tool to study the role of dysbindin in SCZ. Our recent findings reveal that the sdy mice exhibit specific defects of neurosecretion and synaptic morphology in hippocampal neurons. We here further described that sdy manifested schizophrenia-like behaviors such as social withdrawal and cognitive deficits. In sdy hippocampus, the steady-state level of snapin (a SNAP25-binding protein and a synaptic priming regulator) was reduced due to loss of dysbindin. We further characterized that a 30-residue peptide in dysbindin (90-119 amino acids) mediated the interaction with snapin. Our results suggest that the destabilization of snapin in sdy mice may lead to abnormal neurotransmission and therefore abnormal behaviors. This further defines the sdy mutant as a potential model in schizophrenia research.


Assuntos
Proteínas de Transporte/fisiologia , Esquizofrenia/fisiopatologia , Proteínas de Transporte Vesicular/genética , Animais , Comportamento Animal/fisiologia , Proteínas de Transporte/genética , Transtornos Cognitivos/genética , Transtornos Cognitivos/fisiopatologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Disbindina , Proteínas Associadas à Distrofina , Hipocampo/fisiopatologia , Humanos , Immunoblotting , Masculino , Memória/fisiologia , Camundongos , Camundongos Endogâmicos DBA , Camundongos Mutantes , Proteínas de Transporte Vesicular/fisiologia
14.
J Cell Biol ; 181(5): 791-801, 2008 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-18504299

RESUMO

Schizophrenia is one of the most debilitating neuropsychiatric disorders, affecting 0.5-1.0% of the population worldwide. Its pathology, attributed to defects in synaptic transmission, remains elusive. The dystrobrevin-binding protein 1 (DTNBP1) gene, which encodes a coiled-coil protein, dysbindin, is a major susceptibility gene for schizophrenia. Our previous results have demonstrated that the sandy (sdy) mouse harbors a spontaneously occurring deletion in the DTNBP1 gene and expresses no dysbindin protein (Li, W., Q. Zhang, N. Oiso, E.K. Novak, R. Gautam, E.P. O'Brien, C.L. Tinsley, D.J. Blake, R.A. Spritz, N.G. Copeland, et al. 2003. Nat. Genet. 35:84-89). Here, using amperometry, whole-cell patch clamping, and electron microscopy techniques, we discovered specific defects in neurosecretion and vesicular morphology in neuroendocrine cells and hippocampal synapses at the single vesicle level in sdy mice. These defects include larger vesicle size, slower quantal vesicle release, lower release probability, and smaller total population of the readily releasable vesicle pool. These findings suggest that dysbindin functions to regulate exocytosis and vesicle biogenesis in endocrine cells and neurons. Our work also suggests a possible mechanism in the pathogenesis of schizophrenia at the synaptic level.


Assuntos
Proteínas de Transporte/fisiologia , Esquizofrenia/genética , Animais , Proteínas de Transporte/metabolismo , Células Cromafins/metabolismo , Modelos Animais de Doenças , Disbindina , Proteínas Associadas à Distrofina , Eletroquímica/métodos , Deleção de Genes , Cinética , Camundongos , Camundongos Mutantes , Neurônios/metabolismo , Neurotransmissores/metabolismo , Técnicas de Patch-Clamp , Probabilidade , Sinapses/metabolismo
15.
Biochem Biophys Res Commun ; 370(4): 584-8, 2008 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-18395005

RESUMO

System X(c)(-) is an anionic amino acid transport system highly specific for cystine and glutamate. The underlying mechanism of cell death of cultured cells from the subtle gray (sut) mouse which contains an xCT null mutation remains elucidated. Our results show that the death of sut cells is likely caused by apoptosis mediated by c-Jun N-terminal kinase (JNK). The JNK activation triggers both a caspase-dependent (caspases-9 and -3) and an ER stress-mediated (eIF2 and CHOP) pathway to induce apoptosis. These findings suggest the possible pathways involved in the cell death of xCT-deficient cells.


Assuntos
Sistema y+ de Transporte de Aminoácidos/genética , Apoptose/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Melanócitos/fisiologia , Animais , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Retículo Endoplasmático/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Melanócitos/metabolismo , Camundongos , Camundongos Mutantes , Fator de Transcrição CHOP/metabolismo
16.
Biotechnol Lett ; 27(23-24): 1929-34, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16328992

RESUMO

An insect excitatory toxin from Buthus martensii Karsch (BmK IT) was cloned into the expression vector, pTWIN1, and expressed into Escherichia coli BL21 (DE3) host cells. The soluble fusion expression of CBD-intein-BmK IT was obtained. The recombinant BmK IT was purified by two anion-exchange chromatography columns and one gel chromatography column. Bioassays were carried out to verify the toxicity of this recombinant toxin. At the end of a 96 h experimental period, 83% of cotton bollworm larvae were killed with an LT(50) value of 58-62 h. Furthermore, the average weight of larvae fed on BmK IT-containing media was approx 4% of that of the control groups. The results indicate that the expressed and purified recombinant BmK IT has biological activity.


Assuntos
Neurotoxinas/isolamento & purificação , Venenos de Escorpião/química , Animais , Western Blotting , Cromatografia em Gel , Cromatografia por Troca Iônica , Escherichia coli/genética , Escherichia coli/metabolismo , Inteínas/genética , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Lepidópteros/efeitos dos fármacos , Lepidópteros/crescimento & desenvolvimento , Neurotoxinas/genética , Neurotoxinas/farmacologia , Plasmídeos/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Venenos de Escorpião/biossíntese , Venenos de Escorpião/isolamento & purificação , Venenos de Escorpião/farmacologia , Transformação Genética
17.
Biotechnol Lett ; 27(2): 97-102, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15703871

RESUMO

The chitinase gene of Manduca sexta was cloned into the expression vector, pET-28a, and expressed in Escherichia coli BL21 (DE3) host cells. The protein product was expressed in inclusion bodies. After denaturation and renaturation procedures using a Ni2+-NTA affinity chromatography column, soluble chitinase was obtained. The authenticity of the renatured protein was confirmed by Western blotting. Polyclonal antibodies to the purified protein were raised in rabbits. The antibody reacted specifically with the expressed chitinase and was used to quantify its presence in transgenic cotton being developed to resist attack by various insects.


Assuntos
Anticorpos/imunologia , Quitinases/análise , Quitinases/imunologia , Gossypium/genética , Manduca/enzimologia , Plantas Geneticamente Modificadas/genética , Animais , Especificidade de Anticorpos , Western Blotting , Quitinases/genética , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática/métodos , Gossypium/enzimologia , Desnaturação Proteica , Dobramento de Proteína , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
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