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Glaucoma, a blinding neurodegenerative disease, whose risk factors include elevated intraocular pressure (IOP), age, and genetics, is characterized by accelerated and progressive retinal ganglion cell (RGC) death. Despite decades of research, the mechanism of RGC death in glaucoma is still unknown. Here, we demonstrate that the genetic effect of the SIX6 risk variant (rs33912345, His141Asn) is enhanced by another major POAG risk gene, p16INK4a (cyclin-dependent kinase inhibitor 2A, isoform INK4a). We further show that the upregulation of homozygous SIX6 risk alleles (CC) leads to an increase in p16INK4a expression, with subsequent cellular senescence, as evidenced in a mouse model of elevated IOP and in human POAG eyes. Our data indicate that SIX6 and/or IOP promotes POAG by directly increasing p16INK4a expression, leading to RGC senescence in adult human retinas. Our study provides important insights linking genetic susceptibility to the underlying mechanism of RGC death and provides a unified theory of glaucoma pathogenesis.
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Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Glaucoma de Ángulo Abierto/metabolismo , Proteínas de Homeodominio/fisiología , Células Ganglionares de la Retina/fisiología , Transactivadores/fisiología , Secuencia de Aminoácidos , Animales , Estudios de Casos y Controles , Muerte Celular , Línea Celular , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Glaucoma de Ángulo Abierto/genética , Glaucoma de Ángulo Abierto/patología , Humanos , Ratones Endogámicos C57BL , Ratones Noqueados , Datos de Secuencia Molecular , Mutación Missense , Regulación hacia ArribaRESUMEN
In vitro and animal model studies are of great interest for selecting new phytochemicals, including polyphenols with antioxidative properties, as candidates for antidiabetic drugs. This review provides evidence from a critical literature data analysis on the effects of plant extract supplementation in diabetes mellitus management. We considered and meta-analyzed the efficacy of oral supplementation of plant extracts in animal model studies and examined physiological and oxidative stress parameters. Finally, 23 articles were included in the meta-analysis, revealing three plants with experimentally confirmed in vivo and in vitro antidiabetic properties: Gymnema montanum, Momordica charantia and Moringa oleifera. The following parameter changes resulted from an investigation of the supplementation: reduced oxidative stress, decreased insulin resistance, increased insulin release, reduced adiposity, and a modulatory effect on glycolysis and gluconeogenesis, as well as attenuation of diabetes-associated weight loss, reduced fasting blood glucose and lowered oxidative status. A comparison of Gymnema montanum versus Glybenclamide revealed the superiority of extracts over drug administration in some aspects. Although the analyzed extracts are promising candidates for antidiabetic treatment, there is much inconsistent data in the literature. Therefore, ultimate references for using these compounds in the prevention of diabetes are currently not applicable.
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The repair and regeneration of tissues using endogenous stem cells represents an ultimate goal in regenerative medicine. To our knowledge, human lens regeneration has not yet been demonstrated. Currently, the only treatment for cataracts, the leading cause of blindness worldwide, is to extract the cataractous lens and implant an artificial intraocular lens. However, this procedure poses notable risks of complications. Here we isolate lens epithelial stem/progenitor cells (LECs) in mammals and show that Pax6 and Bmi1 are required for LEC renewal. We design a surgical method of cataract removal that preserves endogenous LECs and achieves functional lens regeneration in rabbits and macaques, as well as in human infants with cataracts. Our method differs conceptually from current practice, as it preserves endogenous LECs and their natural environment maximally, and regenerates lenses with visual function. Our approach demonstrates a novel treatment strategy for cataracts and provides a new paradigm for tissue regeneration using endogenous stem cells.
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Catarata/terapia , Cristalino/citología , Cristalino/fisiología , Recuperación de la Función , Regeneración/fisiología , Células Madre/citología , Visión Ocular/fisiología , Animales , Catarata/congénito , Catarata/patología , Catarata/fisiopatología , Extracción de Catarata , Células Epiteliales/citología , Células Epiteliales/metabolismo , Proteínas del Ojo/metabolismo , Proteínas de Homeodominio/metabolismo , Homeostasis , Humanos , Macaca , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box/metabolismo , Complejo Represivo Polycomb 1/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras/metabolismo , Células Madre/metabolismoRESUMEN
The ability to identify a specific cancer using minimally invasive biopsy holds great promise for improving the diagnosis, treatment selection, and prediction of prognosis in cancer. Using whole-genome methylation data from The Cancer Genome Atlas (TCGA) and machine learning methods, we evaluated the utility of DNA methylation for differentiating tumor tissue and normal tissue for four common cancers (breast, colon, liver, and lung). We identified cancer markers in a training cohort of 1,619 tumor samples and 173 matched adjacent normal tissue samples. We replicated our findings in a separate TCGA cohort of 791 tumor samples and 93 matched adjacent normal tissue samples, as well as an independent Chinese cohort of 394 tumor samples and 324 matched adjacent normal tissue samples. The DNA methylation analysis could predict cancer versus normal tissue with more than 95% accuracy in these three cohorts, demonstrating accuracy comparable to typical diagnostic methods. This analysis also correctly identified 29 of 30 colorectal cancer metastases to the liver and 32 of 34 colorectal cancer metastases to the lung. We also found that methylation patterns can predict prognosis and survival. We correlated differential methylation of CpG sites predictive of cancer with expression of associated genes known to be important in cancer biology, showing decreased expression with increased methylation, as expected. We verified gene expression profiles in a mouse model of hepatocellular carcinoma. Taken together, these findings demonstrate the utility of methylation biomarkers for the molecular characterization of cancer, with implications for diagnosis and prognosis.
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Metilación de ADN , Neoplasias/diagnóstico , Neoplasias/genética , Alelos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Estudios de Casos y Controles , Estudios de Cohortes , Neoplasias del Colon/diagnóstico , Neoplasias del Colon/genética , Islas de CpG , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Masculino , Metástasis de la Neoplasia , Neoplasias/mortalidad , Pronóstico , Riesgo , Factores de TiempoRESUMEN
Loss of tumor suppressor adenomatous polyposis coli (APC) activates ß-catenin to initiate colorectal tumorigenesis. However, ß-catenin (CTNNB1) activating mutations rarely occur in human colorectal cancer (CRC). We found that APC loss also results in up-regulation of IL-6 signal transducer (IL-6ST/gp130), thereby activating Src family kinases (SFKs), YAP, and STAT3, which are simultaneously up-regulated in the majority of human CRC. Although, initial YAP activation, which stimulates IL6ST gene transcription, may be caused by reduced serine phosphorylation, sustained YAP activation depends on tyrosine phosphorylation by SFKs, whose inhibition, along with STAT3-activating JAK kinases, causes regression of established colorectal tumors. These results explain why APC loss is a more potent initiating event than the mere activation of CTNNB1.
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Proteína de la Poliposis Adenomatosa del Colon/metabolismo , Neoplasias Colorrectales/metabolismo , Receptor gp130 de Citocinas/metabolismo , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Proteína de la Poliposis Adenomatosa del Colon/genética , Adulto , Anciano , Animales , Carcinogénesis/genética , Carcinogénesis/metabolismo , Proteínas de Ciclo Celular , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Receptor gp130 de Citocinas/genética , Femenino , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Persona de Mediana Edad , Mutación , beta Catenina/genética , beta Catenina/metabolismoRESUMEN
The macula and fovea located at the optical centre of the retina make primate visual perception unique among mammals. Our current understanding of retina ontogenesis is primarily based on animal models having no macula and no fovea. However, the pigeon retina and the human macula share a number of structural and functional properties that justify introducing the former as a new model system for retina development. Comparative transcriptome analysis of pigeon and chicken retinas at different embryonic stages reveals that the genetic programmes underlying cell differentiation are postponed in the pigeon until the end of the period of cell proliferation. We show that the late onset of neurogenesis has a profound effect on the developmental patterning of the pigeon retina, which is at odds with the current models of retina development. The uncoupling of tissue growth and neurogenesis is shown to result from the fact that the pigeon retinal epithelium is inhibitory to cell differentiation. The sum of these developmental features allows the pigeon to build a retina that displays the structural and functional traits typical of primate macula and fovea.
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Columbidae/embriología , Neurogénesis/fisiología , Retina/embriología , Células Ganglionares de la Retina/citología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Proliferación Celular , Embrión de Pollo , Perfilación de la Expresión Génica , Retina/citología , Retina/fisiología , Visión Ocular/fisiología , Agudeza Visual/fisiologíaRESUMEN
AIMS: Atrial fibrillation (AF) is a risk factor for dementia among ischaemic stroke patients in whom the AF was known before the stroke (KAF). Atrial fibrillation detected after stroke (AFDAS) has a different profile compared to KAF, including less frequent cardiovascular comorbidities and lower CHA2-DS2-VASC scores. Currently, it is unknown if AFDAS is also associated with increased dementia risk. We assessed the association between AFDAS and the incident risk of dementia. We also evaluated whether the use of oral anticoagulants (OAC) was associated with lower dementia risk among AFDAS patients. METHODS AND RESULTS: In this cohort study, we classified 9791 first-ever ischaemic stroke patients from the Ontario Stroke Registry into four groups: (i) No AF, (ii) KAF, (iii) Inpatient AFDAS (diagnosed during admission), and (iv) Outpatient AFDAS (diagnosed after discharge). We used multivariable Cox proportional models to estimate hazard ratios (HR) for the association between AFDAS and incident dementia risk. Dementia was determined through administrative datasets based on previously validated algorithms. In adjusted analyses, the dementia risk was higher for inpatient AFDAS [HR 1.78, 95% confidence interval (CI) 1.51-2.10] and outpatient AFDAS (HR 1.74, 95% CI 1.47-2.05) relative to no AF. Oral anticoagulants use was associated with lower dementia risk among patients with inpatient AFDAS (HR 0.58, 95% CI 0.43-0.79) and outpatient AFDAS (HR 0.60, 95% CI 0.43-0.83). CONCLUSION: Atrial fibrillation detected after stroke was independently associated with higher risk of dementia relative to no AF. Among patients with AFDAS, the use of OACs was associated with lower dementia risk.
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Fibrilación Atrial/epidemiología , Demencia/epidemiología , Accidente Cerebrovascular Isquémico/epidemiología , Anciano , Anciano de 80 o más Años , Atención Ambulatoria , Anticoagulantes/uso terapéutico , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/tratamiento farmacológico , Estudios de Cohortes , Femenino , Accidente Cerebrovascular Hemorrágico/epidemiología , Hospitalización , Humanos , Incidencia , Masculino , Mortalidad , Ontario/epidemiología , Modelos de Riesgos Proporcionales , Factores Protectores , Recurrencia , Factores de Riesgo , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Enfermedades no DiagnosticadasRESUMEN
As a key component of the vertebrate neuroendocrine system, the pituitary gland relies on the progressive and coordinated development of distinct hormone-producing cell types and an invading vascular network. The molecular mechanisms that drive formation of the pituitary vasculature, which is necessary for regulated synthesis and secretion of hormones that maintain homeostasis, metabolism, and endocrine function, remain poorly understood. Here, we report that expression of integrin ß1 in embryonic pituitary epithelial cells is required for angiogenesis in the developing mouse pituitary gland. Deletion of pituitary epithelial integrin ß1 before the onset of angiogenesis resulted in failure of invading endothelial cells to recruit pericytes efficiently, whereas deletion later in embryogenesis led to decreased vascular density and lumen formation. In both cases, lack of epithelial integrin ß1 was associated with a complete absence of vasculature in the pituitary gland at birth. Within pituitary epithelial cells, integrin ß1 directs a large transcriptional program that includes components of the extracellular matrix and associated signaling factors that are linked to the observed non-cell-autonomous effects on angiogenesis. We conclude that epithelial integrin ß1 functions as a critical and canonical regulator of developmental angiogenesis in the pituitary gland, thus providing insight into the long-standing systems biology conundrum of how vascular invasion is coordinated with tissue development.
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Desarrollo Embrionario , Células Epiteliales/metabolismo , Integrina beta1/metabolismo , Neovascularización Fisiológica , Hipófisis/citología , Hipófisis/embriología , Animales , Animales Recién Nacidos , Recuento de Células , Diferenciación Celular , Desarrollo Embrionario/genética , Células Endoteliales/citología , Células Endoteliales/metabolismo , Matriz Extracelular/metabolismo , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica , Marcación de Gen , Integrasas/metabolismo , Ratones , Neovascularización Fisiológica/genética , Factores de Transcripción Paired Box/metabolismo , Pericitos/citología , Pericitos/metabolismo , Fenotipo , Hipófisis/metabolismo , Análisis de Secuencia de ARN , Factores de Tiempo , Factor C de Crecimiento Endotelial Vascular/metabolismoRESUMEN
De Dreu and Gross (D&G) seem to have disregarded some relevant experimental literature on games of conflict, most notably variations on "matching pennies" games. While in such games, "attacker" and "defender" are typically not explicitly labelled, players' differentiated roles yield naturally to such notions. These studies partly validate some of D&G's findings and interpretations.
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Conflicto PsicológicoRESUMEN
An effective blood-based method for the diagnosis and prognosis of hepatocellular carcinoma (HCC) has not yet been developed. Circulating tumour DNA (ctDNA) carrying cancer-specific genetic and epigenetic aberrations may enable a noninvasive 'liquid biopsy' for diagnosis and monitoring of cancer. Here, we identified an HCC-specific methylation marker panel by comparing HCC tissue and normal blood leukocytes and showed that methylation profiles of HCC tumour DNA and matched plasma ctDNA are highly correlated. Using cfDNA samples from a large cohort of 1,098 HCC patients and 835 normal controls, we constructed a diagnostic prediction model that showed high diagnostic specificity and sensitivity (P < 0.001) and was highly correlated with tumour burden, treatment response, and stage. Additionally, we constructed a prognostic prediction model that effectively predicted prognosis and survival (P < 0.001). Together, these findings demonstrate in a large clinical cohort the utility of ctDNA methylation markers in the diagnosis, surveillance, and prognosis of HCC.
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Biomarcadores de Tumor , Carcinoma Hepatocelular , ADN Tumoral Circulante , Metilación de ADN , Neoplasias Hepáticas , Modelos Biológicos , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , ADN Tumoral Circulante/sangre , ADN Tumoral Circulante/genética , Femenino , Humanos , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Masculino , PronósticoRESUMEN
Noninvasive prenatal testing (NIPT) using sequencing of fetal cell-free DNA from maternal plasma has enabled accurate prenatal diagnosis of aneuploidy and become increasingly accepted in clinical practice. We investigated whether NIPT using semiconductor sequencing platform (SSP) could reliably detect subchromosomal deletions/duplications in women carrying high-risk fetuses. We first showed that increasing concentration of abnormal DNA and sequencing depth improved detection. Subsequently, we analyzed plasma from 1,456 pregnant women to develop a method for estimating fetal DNA concentration based on the size distribution of DNA fragments. Finally, we collected plasma from 1,476 pregnant women with fetal structural abnormalities detected on ultrasound who also underwent an invasive diagnostic procedure. We used SSP of maternal plasma DNA to detect subchromosomal abnormalities and validated our results with array comparative genomic hybridization (aCGH). With 3.5 million reads, SSP detected 56 of 78 (71.8%) subchromosomal abnormalities detected by aCGH. With increased sequencing depth up to 10 million reads and restriction of the size of abnormalities to more than 1 Mb, sensitivity improved to 69 of 73 (94.5%). Of 55 false-positive samples, 35 were caused by deletions/duplications present in maternal DNA, indicating the necessity of a validation test to exclude maternal karyotype abnormalities. This study shows that detection of fetal subchromosomal abnormalities is a viable extension of NIPT based on SSP. Although we focused on the application of cell-free DNA sequencing for NIPT, we believe that this method has broader applications for genetic diagnosis, such as analysis of circulating tumor DNA for detection of cancer.
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Aberraciones Cromosómicas/embriología , ADN/sangre , Feto/anomalías , Diagnóstico Prenatal/métodos , Semiconductores , Análisis de Secuencia de ADN/métodos , Sistema Libre de Células , Deleción Cromosómica , Duplicación Cromosómica , Hibridación Genómica Comparativa , Femenino , Humanos , Peso Molecular , EmbarazoRESUMEN
PAX6 is a master regulatory gene involved in neuronal cell fate specification. It also plays a critical role in early eye field and subsequent limbal stem cell (LSC) determination during eye development. Defects in Pax6 cause aniridia and LSC deficiency in humans and the Sey (Small eye) phenotype in mice (Massé, K., Bhamra, S., Eason, R., Dale, N., and Jones, E. A. (2007) Nature 449, 1058-1062). However, how PAX6 specifies LSC and corneal fates during eye development is not well understood. Here, we show that PAX6 is expressed in the primitive eye cup and later in corneal tissue progenitors in early embryonic development. In contrast, p63 expression commences after that of PAX6 in ocular adnexal and skin tissue progenitors and later in LSCs. Using an in vitro feeder-free culture system, we show that PAX6 knockdown in LSCs led to up-regulation of skin epidermis-specific keratins concomitant with differentiation to a skin fate. Using gene expression analysis, we identified the involvement of Notch, Wnt, and TGF-ß signaling pathways in LSC fate determination. Thus, loss of PAX6 converts LSCs to epidermal stem cells, as demonstrated by a switch in the keratin gene expression profile and by the appearance of congenital dermoid tissue.
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Linaje de la Célula/fisiología , Proteínas del Ojo/fisiología , Proteínas de Homeodominio/fisiología , Sistema Límbico/citología , Factores de Transcripción Paired Box/fisiología , Proteínas Represoras/fisiología , Células Madre/citología , Animales , Córnea/embriología , Proteínas del Ojo/genética , Perfilación de la Expresión Génica , Proteínas de Homeodominio/genética , Humanos , Sistema Límbico/metabolismo , Proteínas de la Membrana/genética , Ratones , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box/genética , Proteínas Represoras/genética , Transducción de Señal , Células Madre/metabolismoRESUMEN
Maternal alcohol consumption during gestation can cause serious injury to the fetus, and may result in a range of physiological and behavioral impairments, including increased seizure susceptibility, that are collectively termed fetal alcohol spectrum disorder (FASD). The cellular mechanisms underlying increased seizure susceptibility in FASD are not well understood, but could involve altered excitatory coupling of neuronal populations mediated by gap junction proteins. We utilized a mouse model of the prenatal alcohol exposure (PAE) to study the expression pattern of connexin (Cx) major components of gap junctions, and pannexin proteins, which form membrane channels, in the brain of 2-3weeks old PAE and control postnatal offspring. PAE during the first trimester-equivalent period of pregnancy in mice resulted in significant up-regulation of Cx30 mRNA and Cx30 total protein in the hippocampus of PAE animals compared to age-matched controls. Surface level expression of both dimeric and monomeric Cx30 were also found to be significantly up-regulated in both hippocampus and cerebral cortex of PAE animals compared to age-matched controls. On the membrane surface, the fast migrating form of Cx43 was found to be up-regulated in the hippocampus of PAE mice. However, we did not see any up-regulation of the phosphorylated forms of Cx43 on the membrane surface. These results indicate that the expression and processing of astrocytic connexins (Cx30, Cx43) are up-regulated in the brain of PAE offspring, and these changes could play a role in the cerebral hyperexcitability observed in these animals.
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Alcoholes/farmacología , Astrocitos/efectos de los fármacos , Conexina 43/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Animales , Astrocitos/metabolismo , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Conexina 30/genética , Conexina 30/metabolismo , Conexina 43/genética , Modelos Animales de Enfermedad , Femenino , Uniones Comunicantes/efectos de los fármacos , Uniones Comunicantes/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Ratones Endogámicos C57BL , Neuronas/efectos de los fármacos , Neuronas/metabolismo , EmbarazoRESUMEN
BACKGROUND: Mean platelet volume (MPV) is a simple and reliable indicator of platelet size that correlates with platelet activation and their ability to aggregate. We studied the predictive value of MPV in patients with non-ST-segment elevation myocardial infarction (NSTEMI) treated with percutaneous coronary intervention (PCI). METHODS: We analyzed the consecutive records of 1001 patients who were hospitalized due to NSTEMI at our center. The primary end point was a composite end point that included the rates of all-cause death, non-fatal myocardial infarction, and acute coronary syndrome (ACS) driven revascularization at 12 months. The enrolled patients were stratified according to the quartile of the MPV level at admission. RESULTS: Along with the increasing quartile of MPV, the 12-month composite end point increased significantly (p = 0.010), and this association remained significant after the risk-adjusted analyses (per 1 fL higher MPV; adjusted hazard ratio [HR] 1.13; 95% confidence interval [CI] 1.02-1.27; p = 0.026). In the multivariate analysis, the MPV was also an independent factor of all-cause mortality (per 1 fL increase; adjusted HR 1.34; 95% CI 1.12-1.61; p = 0.0014) and death or non-fatal myocardial infarction (per 1 fL increase; adjusted HR 1.16; 95% CI 1.03-1.31; p = 0.017). CONCLUSION: In patients with NSTEMI treated with PCI, a high MPV value was associated with a significantly increased incidence of long-term adverse events, particularly for all-cause mortality.
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Volúmen Plaquetario Medio , Infarto del Miocardio sin Elevación del ST/sangre , Infarto del Miocardio sin Elevación del ST/terapia , Intervención Coronaria Percutánea , Síndrome Coronario Agudo , Anciano , Anciano de 80 o más Años , Biomarcadores , Plaquetas , Causas de Muerte , Comorbilidad , Angiografía Coronaria , Femenino , Mortalidad Hospitalaria , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Infarto del Miocardio , Infarto del Miocardio sin Elevación del ST/diagnóstico , Infarto del Miocardio sin Elevación del ST/mortalidad , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Riesgo , Resultado del TratamientoRESUMEN
Enhanced motivation to take drugs is a central characteristic of addiction, yet the neural underpinning of this maladaptive behavior is still largely unknown. Here, we report a D1-like dopamine receptor (DRD1)-mediated long-term potentiation of GABAA-IPSCs (D1-LTPGABA) in the oval bed nucleus of the stria terminalis that was positively correlated with motivation to self-administer cocaine in rats. Likewise, in vivo intra-oval bed nucleus of the stria terminalis DRD1 pharmacological blockade reduced lever pressing for cocaine more effectively in rats showing enhanced motivation toward cocaine. D1-LTPGABA resulted from enhanced function and expression of G-protein-independent DRD1 coupled to c-Src tyrosine kinases and required local release of neurotensin. There was no D1-LTPGABA in rats that self-administered sucrose, in those with limited cocaine self-administration experience, or in those that received cocaine passively (yoked). Therefore, our study reveals a novel neurophysiological mechanism contributing to individual motivation to self-administer cocaine, a critical psychobiological element of compulsive drug use and addiction.
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Cocaína/administración & dosificación , Inhibidores de Captación de Dopamina/administración & dosificación , Potenciación a Largo Plazo/fisiología , Motivación/fisiología , Receptores de Dopamina D1/metabolismo , Sinapsis/fisiología , Ácido gamma-Aminobutírico/metabolismo , Animales , Dopamina/metabolismo , Potenciales Postsinápticos Inhibidores/efectos de los fármacos , Potenciales Postsinápticos Inhibidores/fisiología , Potenciación a Largo Plazo/efectos de los fármacos , Masculino , Motivación/efectos de los fármacos , Neurotensina/metabolismo , Ratas , Ratas Long-Evans , Refuerzo en Psicología , Autoadministración , Núcleos Septales/efectos de los fármacos , Núcleos Septales/fisiología , Sinapsis/efectos de los fármacosRESUMEN
Suicide is a significant public health concern globally, with its varying rates influenced by numerous factors, including seasonal changes. Online search behaviors, particularly searches related to suicide and mental health, have been proposed as real-time indicators of suicidal ideation in populations. In this study, a cross-sectional time series analysis was conducted, utilizing data on suicide attempts from the Polish Police Headquarters and online search behavior from Google Trends over a decade. Suicide attempt data were analyzed alongside the frequency of Google searches for suicide-related keywords derived from the Polish Corpus of Suicide Notes. A total of 66 keywords were selected for analysis to identify seasonal trends and patterns in search behavior. The study employed linear regression, Seasonal Mann-Kendall tests, and TBATS models to analyze the data. Suicide rates show seasonal patterns, peaking in warmer months. However, keyword searches did not strongly correlate with peak suicide months. This study enhances our understanding of suicide-related search trends and their potential connection to suicide rates. It suggests avenues for more effective prevention efforts and the potential for future algorithms to predict suicide rates and identify at-risk groups.
RESUMEN
Precise spatio-temporal expression of genes in organogenesis is regulated by the coordinated interplay of DNA elements such as promoter and enhancers present in the regulatory region of a given locus. POU1F1 transcription factor plays a crucial role in the development of somatotrophs, lactotrophs and thyrotrophs in the anterior pituitary gland, and in maintaining high expression of growth hormone, prolactin and TSH. In mouse, expression of POU1F1 is controlled by a region fenced by two CTCF sites, containing 5 upstream enhancer elements, designated E-A (5' to 3'). Elements C, B and A correspond to elements shown previously to play a role in pituitary development and hormonal expression; functional roles for elements E and D have not been reported. We performed comparative sequence analysis of this regulatory region and discovered that three elements, B, C and E, are present in all vertebrate groups except Agnatha. One very long (>2 kb) element (A) is unique to mammals suggesting a specific change in regulation of the gene in this group. Using DNA accessibility assay (ATAC-seq) we showed that conserved elements in anterior pituitary of four non-mammals are open, suggesting functionality as regulatory elements. We showed that, in many non-mammalian vertebrates, an additional upstream exon closely follows element E, leading to alternatively spliced transcripts. Here, element E functions as an alternative promoter, but in mammals this feature is lost, suggesting conversion of alternative promoter to enhancer. Our work shows that regulation of POU1F1 changed markedly during the course of vertebrate evolution, use of a low number of enhancer elements combined with alternative promoters in non-mammalian vertebrates being replaced by use of a unique combination of regulatory units in mammals. Most importantly, our work suggests that evolutionary conversion of alternate promoter to enhancer could be one of the evolutionary mechanisms of enhancer birth.
RESUMEN
Mms2 is a ubiquitin E2-variant protein with a very well-documented function in the tolerance pathway that protects both human and yeast cells from the lethal and mutagenic effects of DNA damage. Interestingly, a high expression level of human MMS2 is associated with poor survival prognosis in different cancer diseases. Here we have analyzed the physiological effects of Mms2 overproduction in yeast cells. We show that an increased level of this protein causes a spontaneous mutator effect independent of Ubc13, a cognate partner of Mms2 in the PCNA-polyubiquitinating complex responsible for the template switch. Instead, this new promutagenic role of Mms2 requires Ubc4 (E2) and two ubiquitin ligases of HECT and RING families, Rsp5 and Not4, respectively. We have established that the promutagenic activity of Mms2 is dependent on the activities of error-prone DNA polymerase ζ and Rev1. Additionally, it requires the ubiquitination of K164 in PCNA which facilitates recruitment of these translesion polymerases to the replication complex. Importantly, we have established also that the cellular abundance of Mms2 influences the cellular level of Pol3, the catalytic subunit of replicative DNA polymerase δ. Lack of Mms2 increases the Pol3 abundance, whereas in response to Mms2 overproduction the Pol3 level decreases. We hypothesize that increased levels of spontaneous mutagenesis may result from the Mms2-induced reduction in Pol3 accumulation leading to increased participation of error-prone polymerase ζ in the replication complex.
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Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/metabolismo , Replicación del ADN , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Mutagénesis , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo , Daño del ADN , Ubiquitinas/genética , Ubiquitinas/metabolismo , Ubiquitinas/farmacología , ADN Polimerasa III/genéticaRESUMEN
Diabetes mellitus is a chronic metabolic disorder characterized by hyperglycaemia and oxidative stress. Oxidative stress plays a crucial role in the development and progression of diabetes and its complications. Nutritional antioxidants derived from dietary sources have gained significant attention due to their potential to improve antidiabetic therapy. This review will delve into the world of polyphenols, investigating their origins in plants, metabolism in the human body, and relevance to the antioxidant mechanism in the context of improving antidiabetic therapy by attenuating oxidative stress, improving insulin sensitivity, and preserving ß-cell function. The potential mechanisms of, clinical evidence for, and future perspectives on nutritional antioxidants as adjuvant therapy in diabetes management are discussed.