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1.
Proc Natl Acad Sci U S A ; 113(1): 182-7, 2016 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-26677873

RESUMEN

Macroautophagy is a key stress-response pathway that can suppress or promote tumorigenesis depending on the cellular context. Notably, Kirsten rat sarcoma (KRAS)-driven tumors have been reported to rely on macroautophagy for growth and survival, suggesting a potential therapeutic approach of using autophagy inhibitors based on genetic stratification. In this study, we evaluated whether KRAS mutation status can predict the efficacy to macroautophagy inhibition. By profiling 47 cell lines with pharmacological and genetic loss-of-function tools, we were unable to confirm that KRAS-driven tumor lines require macroautophagy for growth. Deletion of autophagy-related 7 (ATG7) by genome editing completely blocked macroautophagy in several tumor lines with oncogenic mutations in KRAS but did not inhibit cell proliferation in vitro or tumorigenesis in vivo. Furthermore, ATG7 knockout did not sensitize cells to irradiation or to several anticancer agents tested. Interestingly, ATG7-deficient and -proficient cells were equally sensitive to the antiproliferative effect of chloroquine, a lysosomotropic agent often used as a pharmacological tool to evaluate the response to macroautophagy inhibition. Moreover, both cell types manifested synergistic growth inhibition when treated with chloroquine plus the tyrosine kinase inhibitors erlotinib or sunitinib, suggesting that the antiproliferative effects of chloroquine are independent of its suppressive actions on autophagy.


Asunto(s)
Antineoplásicos/farmacología , Autofagia/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Cloroquina/farmacología , Resistencia a Antineoplásicos/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Autofagia/genética , Proteína 7 Relacionada con la Autofagia , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Clorhidrato de Erlotinib/farmacología , Técnicas de Inactivación de Genes , Humanos , Indoles/farmacología , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Pirroles/farmacología , Tolerancia a Radiación/genética , Sunitinib , Enzimas Activadoras de Ubiquitina/genética
2.
Nature ; 461(7264): 614-20, 2009 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-19759537

RESUMEN

The stability of the Wnt pathway transcription factor beta-catenin is tightly regulated by the multi-subunit destruction complex. Deregulated Wnt pathway activity has been implicated in many cancers, making this pathway an attractive target for anticancer therapies. However, the development of targeted Wnt pathway inhibitors has been hampered by the limited number of pathway components that are amenable to small molecule inhibition. Here, we used a chemical genetic screen to identify a small molecule, XAV939, which selectively inhibits beta-catenin-mediated transcription. XAV939 stimulates beta-catenin degradation by stabilizing axin, the concentration-limiting component of the destruction complex. Using a quantitative chemical proteomic approach, we discovered that XAV939 stabilizes axin by inhibiting the poly-ADP-ribosylating enzymes tankyrase 1 and tankyrase 2. Both tankyrase isoforms interact with a highly conserved domain of axin and stimulate its degradation through the ubiquitin-proteasome pathway. Thus, our study provides new mechanistic insights into the regulation of axin protein homeostasis and presents new avenues for targeted Wnt pathway therapies.


Asunto(s)
Proteínas Represoras/metabolismo , Transducción de Señal/efectos de los fármacos , Tanquirasas/antagonistas & inhibidores , Proteínas Wnt/antagonistas & inhibidores , Proteína Axina , División Celular/efectos de los fármacos , Línea Celular , Línea Celular Tumoral , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Compuestos Heterocíclicos con 3 Anillos/farmacología , Humanos , Complejo de la Endopetidasa Proteasomal/metabolismo , Unión Proteica , Proteómica , Proteínas Represoras/química , Tanquirasas/metabolismo , Transcripción Genética/efectos de los fármacos , Ubiquitina/metabolismo , Ubiquitinación , Proteínas Wnt/metabolismo , beta Catenina/antagonistas & inhibidores , beta Catenina/metabolismo
3.
Food Chem ; 456: 139940, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-38870807

RESUMEN

The MobileNetV3-based improved sine-cosine algorithm (ISCA-MobileNetV3) was combined with an artificial olfactory sensor (AOS) to address the redundancy in olfactory arrays, thereby achieving low-cost and high-precision detection of mycotoxin-contaminated maize. Specifically, volatile organic compounds of maize interacted with unoptimized AOS containing eight porphyrins and eight dye-attached nanocomposites to obtain the scent fingerprints for constructing the initial data set. The optimal decision model was MobileNetV3, with more than 98.5% classification accuracy, and its output training loss would be input into the optimizer ISCA. Remarkably, the number of olfactory arrays was reduced from 16 to 6 by ISCA-MobileNetV3 with about a 1% decrease in classification accuracy. Additionally, the developed system showed that each online evaluation was less than one second on average, demonstrating outstanding real-time performance for ensuring food safety. Therefore, AOS combined with ISCA-MobileNetV3 will encourage the development of an affordable and on-site platform for maize quality detection.


Asunto(s)
Contaminación de Alimentos , Micotoxinas , Zea mays , Zea mays/química , Micotoxinas/análisis , Contaminación de Alimentos/análisis , Compuestos Orgánicos Volátiles/química , Algoritmos
4.
Transl Psychiatry ; 14(1): 23, 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38218952

RESUMEN

There is significant heterogeneity in individual responses to antipsychotic drugs, but there is no reliable predictor of antipsychotics response in first-episode psychosis. This study aimed to investigate whether psychotic symptom-related alterations in fractional anisotropy (FA) and mean diffusivity (MD) of white matter (WM) at the early stage of the disorder may aid in the individualized prediction of drug response. Sixty-eight first-episode patients underwent baseline structural MRI scans and were subsequently randomized to receive a single atypical antipsychotic throughout the first 12 weeks. Clinical symptoms were evaluated using the eight "core symptoms" selected from the Positive and Negative Syndrome Scale (PANSS-8). Follow-up assessments were conducted at the 4th, 8th, and 12th weeks by trained psychiatrists. LASSO regression model and cross-validation were conducted to examine the performance of baseline symptom-related alterations FA and MD of WM in the prediction of individualized treatment outcome. Fifty patients completed both clinical follow-up assessments by the 8th and 12th weeks. 30 patients were classified as responders, and 20 patients were classified as nonresponders. At baseline, the altered diffusion properties of fiber tracts in the anterior thalamic radiation, corticospinal tract, callosum forceps minor, longitudinal fasciculi (ILF), inferior frontal-occipital fasciculi (IFOF) and superior longitudinal fasciculus (SLF) were related to the severity of symptoms. These abnormal fiber tracts, especially the ILF, IFOF, and SLF, significantly predicted the response to antipsychotic treatment at the individual level (AUC = 0.828, P < 0.001). These findings demonstrate that early microstructural WM changes contribute to the pathophysiology of psychosis and may serve as meaningful individualized predictors of response to antipsychotics.


Asunto(s)
Antipsicóticos , Trastornos Psicóticos , Esquizofrenia , Sustancia Blanca , Humanos , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/tratamiento farmacológico , Sustancia Blanca/diagnóstico por imagen , Antipsicóticos/uso terapéutico , Imagen de Difusión Tensora , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/tratamiento farmacológico , Anisotropía , Encéfalo/diagnóstico por imagen
5.
Proc Natl Acad Sci U S A ; 107(35): 15473-8, 2010 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-20713706

RESUMEN

Disregulated Wnt/beta-catenin signaling has been linked to various human diseases, including cancers. Inhibitors of oncogenic Wnt signaling are likely to have a therapeutic effect in cancers. LRP5 and LRP6 are closely related membrane coreceptors for Wnt proteins. Using a phage-display library, we identified anti-LRP6 antibodies that either inhibit or enhance Wnt signaling. Two classes of LRP6 antagonistic antibodies were discovered: one class specifically inhibits Wnt proteins represented by Wnt1, whereas the second class specifically inhibits Wnt proteins represented by Wnt3a. Epitope-mapping experiments indicated that Wnt1 class-specific antibodies bind to the first propeller and Wnt3a class-specific antibodies bind to the third propeller of LRP6, suggesting that Wnt1- and Wnt3a-class proteins interact with distinct LRP6 propeller domains. This conclusion is further supported by the structural functional analysis of LRP5/6 and the finding that the Wnt antagonist Sclerostin interacts with the first propeller of LRP5/6 and preferentially inhibits the Wnt1-class proteins. We also show that Wnt1 or Wnt3a class-specific anti-LRP6 antibodies specifically block growth of MMTV-Wnt1 or MMTV-Wnt3 xenografts in vivo. Therapeutic application of these antibodies could be limited without knowing the type of Wnt proteins expressed in cancers. This is further complicated by our finding that bivalent LRP6 antibodies sensitize cells to the nonblocked class of Wnt proteins. The generation of a biparatopic LRP6 antibody blocks both Wnt1- and Wnt3a-mediated signaling without showing agonistic activity. Our studies provide insights into Wnt-induced LRP5/6 activation and show the potential utility of LRP6 antibodies in Wnt-driven cancer.


Asunto(s)
Anticuerpos/farmacología , Proteínas Relacionadas con Receptor de LDL/inmunología , Ligandos , Proteínas Wnt/metabolismo , Animales , Anticuerpos/inmunología , Línea Celular , Transformación Celular Viral , Femenino , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Immunoblotting , Proteínas Relacionadas con Receptor de LDL/genética , Proteínas Relacionadas con Receptor de LDL/metabolismo , Proteína-6 Relacionada a Receptor de Lipoproteína de Baja Densidad , Virus del Tumor Mamario del Ratón/genética , Ratones , Ratones Desnudos , Neoplasias Experimentales/patología , Neoplasias Experimentales/prevención & control , Unión Proteica/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Carga Tumoral/efectos de los fármacos , Proteínas Wnt/genética , Proteína Wnt1/genética , Proteína Wnt1/metabolismo , Proteína Wnt3 , Proteína Wnt3A , Ensayos Antitumor por Modelo de Xenoinjerto , beta Catenina/genética , beta Catenina/metabolismo
6.
Nat Genet ; 30(2): 185-9, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11818962

RESUMEN

Treatment with N-ethyl-N-nitrosourea (ENU) efficiently generates single-nucleotide mutations in mice. Along with the renewed interest in this approach, much attention has been given recently to large screens with broad aims; however, more finely focused studies have proven very productive as well. Here we show how mutagenesis together with genetic mapping can facilitate the rapid characterization of recessive loci required for normal embryonic development. We screened third-generation progeny of mutagenized mice at embryonic day (E) 18.5 for abnormalities of organogenesis. We ascertained 15 monogenic mutations in the 54 families that were comprehensively analyzed. We carried out the experiment as an outcross, which facilitated the genetic mapping of the mutations by haplotype analysis. We mapped seven of the mutations and identified the affected locus in two lines. Using a hierarchical approach, it is possible to maximize the efficiency of this analysis so that it can be carried out easily with modest infrastructure and resources.


Asunto(s)
Desarrollo Embrionario y Fetal/genética , Etilnitrosourea/toxicidad , Mutagénesis , Mutación , Animales , Secuencia de Bases , Mapeo Cromosómico , ADN/genética , Análisis Mutacional de ADN , Femenino , Genes Recesivos , Haplotipos , Masculino , Ratones , Ratones Endogámicos A , Ratones Endogámicos BALB C , Fenotipo , Embarazo
7.
Schizophr Bull ; 49(3): 697-705, 2023 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-37010371

RESUMEN

BACKGROUND AND HYPOTHESIS: Early prediction of treatment response to antipsychotics in schizophrenia remains a challenge in clinical practice. This study aimed to investigate if brain morphometries including gray matter volume and cortical thickness could serve as potential predictive biomarkers in first-episode schizophrenia. STUDY DESIGN: Sixty-eight drug-naïve first-episode patients underwent baseline structural MRI scans and were subsequently randomized to receive a single antipsychotic throughout the first 12 weeks. Assessments for symptoms and social functioning were conducted by eight "core symptoms" selected from the Positive and Negative Syndrome Scale (PANSS-8) and the Personal and Social performance scale (PSP) multiple times during follow-ups. Treatment outcome was evaluated as subject-specific slope coefficients for PANSS-8 and PSP scores using linear mixed model. LASSO regression model were conducted to examine the performance of baseline gray matter volume and cortical thickness in prediction of individualized treatment outcome. STUDY RESULTS: The study showed that individual brain morphometries at baseline, especially the orbitofrontal, temporal and parietal cortex, pallidum and amygdala, significantly predicted 12-week treatment outcome of PANSS-8 (r[predicted vs observed] = 0.49, P = .001) and PSP (r[predicted vs observed] = 0.40, P = .003) in first-episode schizophrenia. Moreover, the gray matter volume performed better than cortical thickness in the prediction the symptom changes (P = .034), while cortical thickness outperformed gray matter volume in the prediction of outcome of social functioning (P = .029). CONCLUSIONS: These findings provide initial evidence that brain morphometry have potential to be used as prognostic predictors for antipsychotic response in patients, encouraging the future investigation of the translational value of these measures in precision psychiatry.


Asunto(s)
Antipsicóticos , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/tratamiento farmacológico , Encéfalo/diagnóstico por imagen , Resultado del Tratamiento , Sustancia Gris/diagnóstico por imagen , Imagen por Resonancia Magnética
8.
J Med Chem ; 66(13): 9095-9119, 2023 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-37399505

RESUMEN

The allosteric inhibitor of the mechanistic target of rapamycin (mTOR) everolimus reduces seizures in tuberous sclerosis complex (TSC) patients through partial inhibition of mTOR functions. Due to its limited brain permeability, we sought to develop a catalytic mTOR inhibitor optimized for central nervous system (CNS) indications. We recently reported an mTOR inhibitor (1) that is able to block mTOR functions in the mouse brain and extend the survival of mice with neuronal-specific ablation of the Tsc1 gene. However, 1 showed the risk of genotoxicity in vitro. Through structure-activity relationship (SAR) optimization, we identified compounds 9 and 11 without genotoxicity risk. In neuronal cell-based models of mTOR hyperactivity, both corrected aberrant mTOR activity and significantly improved the survival rate of mice in the Tsc1 gene knockout model. Unfortunately, 9 and 11 showed limited oral exposures in higher species and dose-limiting toxicities in cynomolgus macaque, respectively. However, they remain optimal tools to explore mTOR hyperactivity in CNS disease models.


Asunto(s)
Inhibidores mTOR , Sirolimus , Ratones , Animales , Síndrome , Sistema Nervioso Central/metabolismo , Encéfalo/metabolismo , Serina-Treonina Quinasas TOR , Adenosina Trifosfato
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 43(2): 210-3, 225, 2012 Mar.
Artículo en Zh | MEDLINE | ID: mdl-22650033

RESUMEN

OBJECTIVE: To investigate the prevalence of four common neuropsychiatric disorders in Tibet, with an aim to providing information support to health planning. METHODS: The survey was carried out in four regions of Tibet. The sampling strategy was adapted from that of a national psychiatric epidemiological survey in China in 1982 and 1993. The Neurosis Screening Inventory, Screening Inventory for Alcohol Dependence and Related Problems, Child Intelligence Screening Inventory, and a questionnaire for the Detection of Epileptic Seizures were administered to the respondents through face to face interview. Those with a positive response and 10% of those with a negative response were further interviewed with the Structured Clinical Interview for DSM-IV Axis I Disorders (research version) (SCID-I ). Anxiety disorders and alcohol used disorders were diagnosed according to the American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders (4th edition) (DSM-IV). Hysteria and mental retardation were diagnosed according to the International Classification of Diseases, 10th edition (ICD-10), and the Chinese Classification of Mental Disorders, 3rd edition (CCMD-3). RESULTS: The point prevalence of neuroses, alcohol-related disorders, mental retardation and epilepsy was 2. 56%, 4. 06%, 0. 28% and 0. 68%, respectively. The lifetime prevalence of neuroses, alcohol-related disorders, mental retardation and epilepsy was 2. 62%, 4. 24%, 0. 28% and 0.72%, respectively. CONCLUSION: Alcohol-related disorders and neuroses are the two common mental health problems in Tibet. Mental retardation and epilepsy are the two serious neuropsychiatric disorders affecting Tibetan children and adolescence. These disorders should be identified as priorities in the reginonal health planning in Tibet.


Asunto(s)
Trastornos Relacionados con Alcohol/epidemiología , Epilepsia/epidemiología , Discapacidad Intelectual/epidemiología , Trastornos Neuróticos/epidemiología , Adolescente , Adulto , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Muestreo , Encuestas y Cuestionarios , Tibet/epidemiología , Adulto Joven
10.
J Med Chem ; 63(3): 1068-1083, 2020 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-31955578

RESUMEN

Recent clinical evaluation of everolimus for seizure reduction in patients with tuberous sclerosis complex (TSC), a disease with overactivated mechanistic target of rapamycin (mTOR) signaling, has demonstrated the therapeutic value of mTOR inhibitors for central nervous system (CNS) indications. Given that everolimus is an incomplete inhibitor of the mTOR function, we sought to develop a new mTOR inhibitor that has improved properties and is suitable for CNS disorders. Starting from an in-house purine-based compound, optimization of the physicochemical properties of a thiazolopyrimidine series led to the discovery of the small molecule 7, a potent and selective brain-penetrant ATP-competitive mTOR inhibitor. In neuronal cell-based models of mTOR hyperactivity, 7 corrected the mTOR pathway activity and the resulting neuronal overgrowth phenotype. The new mTOR inhibitor 7 showed good brain exposure and significantly improved the survival rate of mice with neuronal-specific ablation of the Tsc1 gene. These results demonstrate the potential utility of this tool compound to test therapeutic hypotheses that depend on mTOR hyperactivity in the CNS.


Asunto(s)
Inhibidores de Proteínas Quinasas/uso terapéutico , Pirimidinas/uso terapéutico , Convulsiones/tratamiento farmacológico , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Tiazoles/uso terapéutico , Animales , Anticonvulsivantes/metabolismo , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/uso terapéutico , Sitios de Unión , Encéfalo/efectos de los fármacos , Descubrimiento de Drogas , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/efectos de los fármacos , Unión Proteica , Inhibidores de Proteínas Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacocinética , Pirimidinas/metabolismo , Pirimidinas/farmacocinética , Ratas , Serina-Treonina Quinasas TOR/química , Serina-Treonina Quinasas TOR/metabolismo , Tiazoles/metabolismo , Tiazoles/farmacocinética , Proteína 1 del Complejo de la Esclerosis Tuberosa/genética
11.
Elife ; 52016 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-27351204

RESUMEN

SQSTM1 is an adaptor protein that integrates multiple cellular signaling pathways and whose expression is tightly regulated at the transcriptional and post-translational level. Here, we describe a forward genetic screening paradigm exploiting CRISPR-mediated genome editing coupled to a cell selection step by FACS to identify regulators of SQSTM1. Through systematic comparison of pooled libraries, we show that CRISPR is superior to RNAi in identifying known SQSTM1 modulators. A genome-wide CRISPR screen exposed MTOR signalling and the entire macroautophagy machinery as key regulators of SQSTM1 and identified several novel modulators including HNRNPM, SLC39A14, SRRD, PGK1 and the ufmylation cascade. We show that ufmylation regulates SQSTM1 by eliciting a cell type-specific ER stress response which induces SQSTM1 expression and results in its accumulation in the cytosol. This study validates pooled CRISPR screening as a powerful method to map the repertoire of cellular pathways that regulate the fate of an individual target protein.


Asunto(s)
Regulación de la Expresión Génica , Procesamiento Proteico-Postraduccional , Proteínas/metabolismo , Proteína Sequestosoma-1/metabolismo , Autofagia , Línea Celular , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Citometría de Flujo , Marcación de Gen , Pruebas Genéticas , Humanos , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
12.
JAMA Neurol ; 73(7): 836-845, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27159400

RESUMEN

IMPORTANCE: Focal cortical dysplasia (FCD), hemimegalencephaly, and megalencephaly constitute a spectrum of malformations of cortical development with shared neuropathologic features. These disorders are associated with significant childhood morbidity and mortality. OBJECTIVE: To identify the underlying molecular cause of FCD, hemimegalencephaly, and diffuse megalencephaly. DESIGN, SETTING, AND PARTICIPANTS: Patients with FCD, hemimegalencephaly, or megalencephaly (mean age, 11.7 years; range, 2-32 years) were recruited from Pediatric Hospital A. Meyer, the University of Hong Kong, and Seattle Children's Research Institute from June 2012 to June 2014. Whole-exome sequencing (WES) was performed on 8 children with FCD or hemimegalencephaly using standard-depth (50-60X) sequencing in peripheral samples (blood, saliva, or skin) from the affected child and their parents and deep (150-180X) sequencing in affected brain tissue. Targeted sequencing and WES were used to screen 93 children with molecularly unexplained diffuse or focal brain overgrowth. Histopathologic and functional assays of phosphatidylinositol 3-kinase-AKT (serine/threonine kinase)-mammalian target of rapamycin (mTOR) pathway activity in resected brain tissue and cultured neurons were performed to validate mutations. MAIN OUTCOMES AND MEASURES: Whole-exome sequencing and targeted sequencing identified variants associated with this spectrum of developmental brain disorders. RESULTS: Low-level mosaic mutations of MTOR were identified in brain tissue in 4 children with FCD type 2a with alternative allele fractions ranging from 0.012 to 0.086. Intermediate-level mosaic mutation of MTOR (p.Thr1977Ile) was also identified in 3 unrelated children with diffuse megalencephaly and pigmentary mosaicism in skin. Finally, a constitutional de novo mutation of MTOR (p.Glu1799Lys) was identified in 3 unrelated children with diffuse megalencephaly and intellectual disability. Molecular and functional analysis in 2 children with FCD2a from whom multiple affected brain tissue samples were available revealed a mutation gradient with an epicenter in the most epileptogenic area. When expressed in cultured neurons, all MTOR mutations identified here drive constitutive activation of mTOR complex 1 and enlarged neuronal size. CONCLUSIONS AND RELEVANCE: In this study, mutations of MTOR were associated with a spectrum of brain overgrowth phenotypes extending from FCD type 2a to diffuse megalencephaly, distinguished by different mutations and levels of mosaicism. These mutations may be sufficient to cause cellular hypertrophy in cultured neurons and may provide a demonstration of the pattern of mosaicism in brain and substantiate the link between mosaic mutations of MTOR and pigmentary mosaicism in skin.


Asunto(s)
Malformaciones del Desarrollo Cortical/genética , Megalencefalia/genética , Mosaicismo , Mutación/genética , Serina-Treonina Quinasas TOR/genética , Adolescente , Adulto , Aminoácidos/farmacología , Animales , Células Cultivadas , Corteza Cerebral/citología , Niño , Preescolar , Discapacidades del Desarrollo/diagnóstico por imagen , Discapacidades del Desarrollo/genética , Embrión de Mamíferos , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Estudios de Asociación Genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/deficiencia , Masculino , Malformaciones del Desarrollo Cortical/diagnóstico por imagen , Diana Mecanicista del Complejo 1 de la Rapamicina , Megalencefalia/diagnóstico por imagen , Complejos Multiproteicos/farmacología , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/efectos de los fármacos , Ratas , Estudios Retrospectivos , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/farmacología , Adulto Joven
13.
Neuropsychiatr Dis Treat ; 11: 1437-42, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26089673

RESUMEN

Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is a form of autoimmune encephalitis associated with antibodies against the NR1 subunits of NMDARs. Although new-onset acute prominent psychotic syndromes in patients with NMDAR encephalitis have been well documented, there is a lack of case studies on differential diagnosis and treatment of anti-NMDAR encephalitis after a long-term diagnostic history of functional psychotic disorders. The present study reports an unusual case of anti-NMDAR encephalitis. The patient had been diagnosed with schizophrenia 7 years earlier, and was currently hospitalized for acute-onset psychiatric symptoms. The diagnosis became unclear when the initial psychosis was confounded with considerations of other neurotoxicities (such as neuroleptic malignant syndrome). Finally, identification of specific immunoglobulin G NR1 autoantibodies in the cerebrospinal fluid and greater effectiveness of immunotherapy over antipsychotics alone (which has been well documented in anti-NMDAR encephalitis) indicated the diagnosis of anti-NMDAR encephalitis in this case. Based on the available evidence, however, the relationship between the newly diagnosed anti-NMDAR encephalitis and the seemingly clear, long-term history of schizophrenia in the preceding 7 years is uncertain. This case report illustrates that psychiatrists should consider anti-NMDAR encephalitis and order tests for specific immunoglobulin G NR1 autoantibodies in patients presenting with disorientation, disturbance of consciousness, cognitive deficit, dyskinesia, autonomic disturbance, or rapid deterioration, even with a seemingly clear history of a psychiatric disorder and no specific findings on routine neuroimaging, electroencephalography, or cerebrospinal fluid tests in the early stage of the illness.

14.
Nat Cell Biol ; 16(11): 1069-79, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25327288

RESUMEN

Cells rely on autophagy to clear misfolded proteins and damaged organelles to maintain cellular homeostasis. In this study we use the new autophagy inhibitor PIK-III to screen for autophagy substrates. PIK-III is a selective inhibitor of VPS34 that binds a unique hydrophobic pocket not present in related kinases such as PI(3)Kα. PIK-III acutely inhibits autophagy and de novo lipidation of LC3, and leads to the stabilization of autophagy substrates. By performing ubiquitin-affinity proteomics on PIK-III-treated cells we identified substrates including NCOA4, which accumulates in ATG7-deficient cells and co-localizes with autolysosomes. NCOA4 directly binds ferritin heavy chain-1 (FTH1) to target the iron-binding ferritin complex with a relative molecular mass of 450,000 to autolysosomes following starvation or iron depletion. Interestingly, Ncoa4(-/-) mice exhibit a profound accumulation of iron in splenic macrophages, which are critical for the reutilization of iron from engulfed red blood cells. Taken together, the results of this study provide a new mechanism for selective autophagy of ferritin and reveal a previously unappreciated role for autophagy and NCOA4 in the control of iron homeostasis in vivo.


Asunto(s)
Autofagia/fisiología , Fosfatidilinositol 3-Quinasas Clase III/antagonistas & inhibidores , Ferritinas/metabolismo , Homeostasis/fisiología , Hierro/metabolismo , Coactivadores de Receptor Nuclear/metabolismo , Animales , Autofagia/efectos de los fármacos , Células Cultivadas , Humanos , Lisosomas/metabolismo , Ratones , Fagosomas/metabolismo , Unión Proteica
15.
PLoS One ; 8(7): e68357, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23861892

RESUMEN

The accumulation of aggregated mutant huntingtin (mHtt) inclusion bodies is involved in Huntigton's disease (HD) progression. Medium sized-spiny neurons (MSNs) in the corpus striatum are highly vulnerable to mHtt aggregate accumulation and degeneration, but the mechanisms and pathways involved remain elusive. Here we have developed a new model to study MSNs degeneration in the context of HD. We produced organotypic cortico-striatal slice cultures (CStS) from HD transgenic mice mimicking specific features of HD progression. We then show that induction of autophagy using catalytic inhibitors of mTOR prevents MSNs degeneration in HD CStS. Furthermore, disrupting autophagic flux by overexpressing Atg4b in neurons and slice cultures, accelerated mHtt aggregation and neuronal death, suggesting that Atg4b-dependent autophagic flux influences HD progression. Under these circumstances induction of autophagy using catalytic inhibitors of mTOR was inefficient and did not affect mHtt aggregate accumulation and toxicity, indicating that mTOR inhibition alleviates HD progression by inducing Atg4b-dependent autophagic flux. These results establish modulators of Atg4b-dependent autophagic flux as new potential targets in the treatment of HD.


Asunto(s)
Autofagia , Cisteína Endopeptidasas/metabolismo , Progresión de la Enfermedad , Enfermedad de Huntington/metabolismo , Enfermedad de Huntington/patología , Animales , Autofagia/efectos de los fármacos , Proteínas Relacionadas con la Autofagia , Biocatálisis/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/patología , Modelos Animales de Enfermedad , Proteína Huntingtina , Enfermedad de Huntington/complicaciones , Morfolinas/farmacología , Neostriado/efectos de los fármacos , Neostriado/patología , Degeneración Nerviosa/complicaciones , Degeneración Nerviosa/patología , Proteínas del Tejido Nervioso/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Proteínas Nucleares/metabolismo , Fenotipo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/metabolismo
16.
Schizophr Res ; 134(2-3): 143-50, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22113155

RESUMEN

BACKGROUND: Previous studies have shown that patients with schizophrenia show abnormalities in brain activation when processing emotional faces. However, very few studies have examined if such abnormalities are also found in non-western patient samples and in at-risk individuals. The current study explored whether patients with schizophrenia and siblings of patients in China would show abnormal brain activation during processing of emotional faces. METHODS: Thirty-six participants (three groups of twelve each of patients with schizophrenia, nonpsychotic siblings, and healthy controls) took part in the study. They were administered a task to judge emotional valence of three types of faces (viz., happy, fearful, and neutral), during fMRI scanning. RESULTS: Results of this study demonstrated that patients with schizophrenia showed abnormalities in the social brain neural circuit during facial emotion processing, in comparison with nonpsychotic siblings and healthy controls. Patients with schizophrenia demonstrated lower activation right superior and middle frontal gyrus, left precentral gyrus, left middle temporal gyrus and left insula in comparison with healthy controls; and showed abnormal activation in bilateral inferior and middle frontal gyri, right orbital frontal gyrus, left superior and middle temporal gyrus, bilateral insula, and right superior parietal gyrus/postcentral gyrus when compared with their nonpyschotic siblings. Meanwhile, patients with schizophrenia showed greater activation in left middle frontal gyrus than healthy controls, and overactivation in bilateral middle frontal gyri, right orbital frontal gyrus and left middle temporal gyrus than their nonpsychotic siblings during processing of fearful faces. Moreover, nonpsychotic siblings seemed to share some similar dysfunctions in processing facial expressions as their psychotic probands, the two groups both showed abnormal activation in precentral and superior frontal gyri, and such abnormal activation lied between patients with schizophrenia and healthy controls. CONCLUSIONS: The current findings support the universality of emotion perception impairments in schizophrenia, and also suggest that facial emotion perception might be a potential endophenotype of schizophrenia.


Asunto(s)
Encéfalo/irrigación sanguínea , Emociones , Expresión Facial , Esquizofrenia/patología , Esquizofrenia/fisiopatología , Adulto , Amígdala del Cerebelo/irrigación sanguínea , Análisis de Varianza , Encéfalo/fisiopatología , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/métodos , Masculino , Oxígeno/sangre , Reconocimiento Visual de Modelos/fisiología , Estimulación Luminosa/métodos , Hermanos , Adulto Joven
17.
Nat Cell Biol ; 13(5): 623-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21478859

RESUMEN

The Wnt/ß-catenin signalling pathway plays essential roles in embryonic development and adult tissue homeostasis, and deregulation of this pathway has been linked to cancer. Axin is a concentration-limiting component of the ß-catenin destruction complex, and its stability is regulated by tankyrase. However, the molecular mechanism by which tankyrase-dependent poly(ADP-ribosyl)ation (PARsylation) is coupled to ubiquitylation and degradation of axin remains undefined. Here, we identify RNF146, a RING-domain E3 ubiquitin ligase, as a positive regulator of Wnt signalling. RNF146 promotes Wnt signalling by mediating tankyrase-dependent degradation of axin. Mechanistically, RNF146 directly interacts with poly(ADP-ribose) through its WWE domain, and promotes degradation of PARsylated proteins. Using proteomics approaches, we have identified BLZF1 and CASC3 as further substrates targeted by tankyrase and RNF146 for degradation. Thus, identification of RNF146 as a PARsylation-directed E3 ligase establishes a molecular paradigm that links tankyrase-dependent PARsylation to ubiquitylation. RNF146-dependent protein degradation may emerge as a major mechanism by which tankyrase exerts its function.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Poli Adenosina Difosfato Ribosa/metabolismo , Proteínas Represoras/metabolismo , Transducción de Señal , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Wnt/metabolismo , Secuencia de Aminoácidos , Animales , Proteína Axina , Humanos , Hidrólisis , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Ubiquitina-Proteína Ligasas/química
18.
J Affect Disord ; 135(1-3): 95-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21821294

RESUMEN

BACKGROUND: In European and US studies, patients with major depressive disorder (MDD) report more stressful life events (SLEs) than controls, but this relationship has rarely been studied in Chinese populations. METHODS: Sixteen lifetime SLEs were assessed at interview in two groups of Han Chinese women: 1970 clinically ascertained with recurrent MDD and 2597 matched controls. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression. RESULTS: 60% of controls and 72% of cases reported at least one lifetime SLE. Fourteen of the sixteen SLEs occurred significantly more frequently in those with MDD (median odds ratio of 1.6). The three SLEs most strongly associated with risk for MDD (OR>3.0) preceded the onset of MDD the majority of the time: rape (82%), physical abuse (100%) and serious neglect (99%). LIMITATIONS: Our results may apply to females only. SLEs were rated retrospectively and are subject to biases in recollection. We did not assess contextual information for each life event. CONCLUSIONS: More severe SLEs are more strongly associated with MDD. These results support the involvement of psychosocial adversity in the etiology of MDD in China.


Asunto(s)
Trastorno Depresivo Mayor/etnología , Trastorno Depresivo Mayor/psicología , Acontecimientos que Cambian la Vida , Adulto , Pueblo Asiatico , Estudios de Casos y Controles , China/epidemiología , Depresión , Trastorno Depresivo/etiología , Trastorno Depresivo Mayor/complicaciones , Trastorno Depresivo Mayor/epidemiología , Femenino , Humanos , Modelos Logísticos , Masculino , Trastornos Mentales/complicaciones , Persona de Mediana Edad , Oportunidad Relativa , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Mujeres
19.
Zhonghua Liu Xing Bing Xue Za Zhi ; 30(11): 1160-4, 2009 Nov.
Artículo en Zh | MEDLINE | ID: mdl-20193587

RESUMEN

OBJECTIVE: To explore the reliability and validity of the Children's Impact of Event Scale (Chinese version, CRIES-13) and to determine the value and the optimal cutoff point of the score of CRIES-13 in screening posttraumatic stress disorder (PTSD), so as to provide evidence for PTSD prevention and identify children at risk in Wenchuan earthquake areas. METHODS: A total of 253 children experienced the Wenchuan earthquake were tested through Stratified random cluster sampling. The authors examined CRIES-13's internal consistency, discriminative validity and predictive value of the cut-off. PTSD was assessed with the DSM-IV criteria. Area under the curve while sensitivity, specificity and Youden index were computed based on the receiver operating characteristic curve analysis. Optimal cutoff point was determined by the maximum of Youden index. RESULTS: 20.9% of the subjects were found to have met the DSM-IV criteria for PTSD 7 months after the Wenchuan earthquake accident. The Cronbach's coefficient of CRIES-13 was 0.903 and the mean inter-item correlation coefficients ranged from 0.283 to 0.689, the correlation coefficient of the three factors with the total scale scores ranged from 0.836 to 0.868 while the correlation coefficient among the three factors ranged from 0.568 to 0.718, PTSD cases indicated much higher scores than non-PTSD cases, the Youden index reached maximum value when the total score approached 18 in CRIES-13 with sensitivity and specificity as 81.1% and 76.5% respectively. Consistency check showed that there were no significant differences between the results of CRIES-13 score >/= 32 and clinical diagnosis (Kappa = 0.529) from the screening program. CONCLUSION: CRIES-13 appeared to be a reliable and valid measure for assessing the posttraumatic stress symptoms among children after the earthquake accident in the Wenchuan area. The CRIES-13 seemed to be a useful self-rating diagnostic instrument for survivors with PTSD symptoms as a clinical concern by using a 18 cut-off in total score. Consistency check showed that there was no significant difference between the screening result of CRIES-13 score >/= 32 and clinical diagnosis.


Asunto(s)
Desastres , Terremotos , Escalas de Valoración Psiquiátrica , Trastornos por Estrés Postraumático/diagnóstico , Adolescente , Niño , China , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Estudiantes
20.
Hum Mol Genet ; 14(5): 667-77, 2005 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-15661756

RESUMEN

We have identified waved 3 (wa3), a novel recessive mutation that causes abnormalities of the heart and skin. The cardiac defect results in a severe and rapidly progressive dilated cardiomyopathy. We identified the gene mutated in these mice, which we call NFkB interacting protein1 (Nkip1), using positional cloning. Nkip1 is expressed in skin, heart and vascular endothelium and shares homology with a small family of proteins that play a role in the regulation of transcription factors. A C-terminal fragment of this protein was previously identified as the RelA associated inhibitor (RAI). We show that the full-length protein is larger than previously described, and we confirm that it interacts with NFkB in vivo. Expression analysis of genes known to be regulated by NFkB revealed that Intercellular adhesion molecule 1 (Icam1) expression is consistently elevated in mutant mice. This result suggests that wa3 mutant mice represent a potentially important model for the analysis of the role of inflammatory processes in heart disease.


Asunto(s)
Cardiomiopatías/genética , Mutación , FN-kappa B/metabolismo , Proteínas Represoras/genética , Anomalías Cutáneas/genética , Piel/embriología , Animales , Cardiomiopatías/metabolismo , Mapeo Cromosómico , Cardiopatías Congénitas/genética , Cardiopatías Congénitas/patología , Péptidos y Proteínas de Señalización Intracelular , Ratones , Miocardio/patología , Proteínas Represoras/metabolismo , Análisis de Secuencia de ADN , Análisis de Secuencia de Proteína , Piel/patología , Anomalías Cutáneas/patología
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