RESUMO
Philopatric kin-based societies encourage a narrow breadth of conservative behaviours owing to individuals primarily learning from close kin, promoting behavioural homogeneity. However, weaker social ties beyond kin, and across a behaviourally diverse social landscape, could be sufficient to induce variation and a greater ecological niche breadth. We investigated a network of 457 photo-identified killer whales from Norway (548 encounters in 2008-2021) with diet data available (46 mixed-diet individuals feeding on both fish and mammals, and 411 exclusive fish-eaters) to quantify patterns of association within and between diet groups, and to identify underlying correlates. We genotyped a subset of 106 whales to assess patterns of genetic differentiation. Our results suggested kinship as main driver of social bonds within and among cohesive social units, while diet was most likely a consequence reflective of cultural diffusion, rather than a driver. Flexible associations within and between ecologically diverse social units led to a highly connected network, reducing social and genetic differentiation between diet groups. Our study points to a role of social connectivity, in combination with individual behavioural variation, in influencing population ecology in killer whales.
Assuntos
Orca , Animais , Orca/genética , Comportamento Social , Ecossistema , Comportamento Predatório , DietaRESUMO
The United States has long been the leading destination for Latin Americans seeking refuge. However, in the last 7 years, many children from Mexico and northern Central America, composed of El Salvador, Honduras, and Guatemala, have joined this migratory flow. The experience of forced migration is intense, chronic, and complex for children in their home countries, during their journey, and on arrival in the United States. Their stories can inform clinical practices, such as Psychological First Aid and Trauma-Focused Cognitive Behavioral Therapy, to promote resilience in children in vulnerable conditions.
Assuntos
Emigrantes e Imigrantes , Trauma Psicológico , Criança , Humanos , Estados Unidos , Emigrantes e Imigrantes/psicologia , Terapia Cognitivo-Comportamental , Resiliência Psicológica , Populações VulneráveisRESUMO
Neurodevelopment is a tightly coordinated process, during which the genome is exposed to spectra of endogenous agents at different stages of differentiation. Emerging evidence indicates that DNA damage is an important feature of developing brain, tightly linked to gene expression and neuronal activity. Some of the most frequent DNA damage includes changes to DNA bases, which are recognized by DNA glycosylases and repaired through base excision repair (BER) pathway. The only mammalian DNA glycosylase able to remove frequent alkylated DNA based is alkyladenine DNA glycosylase (Aag, aka Mpg). We recently demonstrated that, besides its role in DNA repair, AAG affects expression of neurodevelopmental genes in human cells. Aag was further proposed to act as reader of epigenetic marks, including 5-hydroxymethylcytosine (5hmC), in the mouse brain. Despite the potential Aag involvement in the key brain processes, the impact of Aag loss on developing brain remains unknown. Here, by using Aag knockout (Aag-/-) mice, we show that Aag absence leads to reduced DNA break levels, evident in lowered number of γH2AX foci in postnatal day 5 (P5) hippocampi. This is accompanied by changes in 5hmC signal intensity in different hippocampal regions. Transcriptome analysis of hippocampi and prefrontal cortex, at different developmental stages, indicates that lack of Aag alters gene expression, primarily of genes involved in regulation of response to stress. Across all developmental stages tested aldehyde dehydrogenase 2 (Aldh2) emerged as one of the most prominent genes deregulated in Aag-dependent manner. In line with the changes in hippocampal DNA damage levels and the gene expression, adult Aag-/- mice exhibit altered behavior, evident in decreased anxiety levels determined in the Elevated Zero Maze and increased alternations in the Elevated T Maze tests. Taken together these results suggests that Aag has functions in modulation of genome dynamics during brain development, important for animal behavior.
Assuntos
DNA Glicosilases , Humanos , Camundongos , Animais , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , DNA , Ansiedade/genética , Encéfalo/metabolismo , Expressão Gênica , Mamíferos/genéticaRESUMO
Synaptic dysfunction and altered synaptic pruning are present in people with Parkinsonian disorders. Dopamine loss and alpha-synuclein accumulation, two hallmarks of Parkinson's disease (PD) pathology, contribute to synaptic dysfunction and reduced synaptic density in PD. Atypical Parkinsonian disorders are likely to have unique spatiotemporal patterns of synaptic density, differentiating them from PD. Therefore, quantification of synaptic density has the potential to support diagnoses, monitor disease progression, and treatment efficacy. Novel radiotracers for positron emission tomography which target the presynaptic vesicle protein SV2A have been developed to quantify presynaptic density. The radiotracers have successfully investigated synaptic density in preclinical models of PD and people with Parkinsonian disorders. Therefore, this review will summarize the preclinical and clinical utilization of SV2A radiotracers in people with Parkinsonian disorders. We will evaluate how SV2A abundance is associated with other imaging modalities and the considerations for interpreting SV2A in Parkinsonian pathology.
Assuntos
Doença de Parkinson , Transtornos Parkinsonianos , Humanos , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/metabolismo , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Sinapses/metabolismo , Dopamina/metabolismo , Encéfalo/metabolismoRESUMO
Rates of youth depression and suicide are rising worldwide and represent public health crises. The present study examined the relationship between trauma history and symptoms of depression, suicidal ideation, and anxiety among suicidal and depressed youth. A diverse group of 1000 8-20-year-olds enrolled in the statewide Texas Youth Depression and Suicide Research Network (TX-YDSRN) reported their trauma history (Traumatic Events Screening Inventory for Children) and symptoms of depression (Patient Health Questionnaire for adolescents; PHQ-A), anxiety (Generalized Anxiety Disorder scale; GAD-7), and suicidality (Concise Health Risk Tracking scale; CHRT-SR). Nearly half of the sample reported exposure to multiple categories of traumatic experiences. Number of trauma exposure categories significantly predicted PHQ-A and GAD-7 scores. Exposure to interpersonal trauma and to sexual trauma were significantly associated with PHQ-A, GAD-7, and CHRT-SR scores. The number of trauma exposure categories was associated with increased levels of anxiety and depression; however, only exposure to interpersonal or sexual trauma was associated with more suicidality. Clinicians should assess trauma exposure in patients seeking psychiatric care, especially for interpersonal and sexual trauma, which may be predictive of increased risk for suicidality in depressed youth. Future work should disentangle the effects of specific trauma types from multiple trauma exposure.
Assuntos
Depressão , Suicídio , Criança , Humanos , Adolescente , Depressão/epidemiologia , Depressão/psicologia , Saúde Mental , Texas/epidemiologia , Psicometria , Suicídio/psicologia , Ideação SuicidaRESUMO
Background: Progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) are atypical parkinsonisms (APs) that are classified as tauopathies. Patients with these APs may present with similar early clinical manifestations to Parkinson's disease (PD), but they prove unresponsive to anti-parkinsonian medications. Objective: The main objective of this meta-analysis was to compare first- and second-generation tau PET tracer efficacy in patients with the APs to identify potential diagnostic biomarkers. Methods: PubMed and Web of Science were searched between January 1, 1999 and December 31, 2022. We included case-control studies that were published in English and report tau PET tracer binding as mean ± SD in at least one region of interest (ROI). Differences in tau PET binding values were meta-analyzed using random-effects meta-analytic models and subgroup analyses based on ROIs in the statistical programming language R (version 4.2.1). Results: Overall, 29 studies with 665 patients were included in the final review. [18F]PI-2620 outperformed first-generation tracers when comparing PSP-HC (g = -1.68, 95% CI: -2.05 to -1.30) and CBD-HC (g = -1.37, 95% CI: -2.25 to -0.49). When comparing PSP-PD, the first-generation tracer, [18F]AV-1451, presented with higher binding to PSP patients (g = -0.80, 95% CI: -1.24 to -0.35). Conclusions: Our results demonstrate the efficacy of [18F]PI-2620 PET in imaging AP-tau. These findings contribute towards identifying a diagnostic imaging biomarker for patients with APs. The main limitation of this study was the heterogeneity of the results. Future studies should conduct AP-PD comparisons with second-generation tracers to confirm the preliminary results found here.
RESUMO
Background: Although chronic pain and obesity are global health crises with substantial healthcare costs, little is known about the relationship between pain perception and eating behaviours. Food consumption has been reported to provide an analgesic effect by the release of neurotransmitters modulating the pain network. However, whether short-term (acute) fasting affects pain perception remains unclear. Purpose: This study aimed to investigate the effect of acute fasting on pain perception and whether attention and mood changes drove the observed changes. Patients and methods: The cold pressor test (CPT) was used to investigate the pain tolerance of 25 healthy participants in both non-fasting and 12-h fasting sessions. They were randomised to either session with a crossover to the other after at least 24â h, with the experimenter blinded to the sessions. The pain tolerance was measured using a Stroop task in both attentive and distracted states. The Profile of Mood States (POMS) questionnaire was used to capture the mood, and a 10-point hunger scale was used to measure hunger. Mixed-effects models were used to investigate the influence of fasting and distraction on pain perception, accounting for the repeated measures. Results: Fasting reduced CPT pain tolerance, with fasting participants twice as likely to withdraw their hands early (hazard ratio = 2.4, 95% CI: 1.3-4.5). Though men tolerated CPT pain longer than women, there was no evidence that men responded to fasting differently than women (p = 0.9). In addition, no evidence supporting that fasting affected attention or mood was found. Nonetheless, it increased hunger scores by 2.7 points on a 10-point scale (95% CI: 1.2-4.2) and decreased blood glucose concentration levels by 0.51â mmol/L (95% CI: 0.19-0.84). Conclusion: Acute fasting reduces pain tolerance in the healthy participants, and this effect is independent of gender and attention or mood changes.
RESUMO
Typically much smaller in number than their mainland counterparts, island populations are ideal systems to investigate genetic threats to small populations. The Svalbard reindeer (Rangifer tarandus platyrhynchus) is an endemic subspecies that colonized the Svalbard archipelago ca. 6,000-8,000 years ago and now shows numerous physiological and morphological adaptations to its arctic habitat. Here, we report a de-novo chromosome-level assembly for Svalbard reindeer and analyze 133 reindeer genomes spanning Svalbard and most of the species' Holarctic range, to examine the genomic consequences of long-term isolation and small population size in this insular subspecies. Empirical data, demographic reconstructions, and forward simulations show that long-term isolation and high inbreeding levels may have facilitated the reduction of highly deleterious-and to a lesser extent, moderately deleterious-variation. Our study indicates that long-term reduced genetic diversity did not preclude local adaptation to the High Arctic, suggesting that even severely bottlenecked populations can retain evolutionary potential.
RESUMO
Synaptic density in the central nervous system can be measured in vivo using PET with [18F]SynVesT-1. While [18F]SynVesT-1 has been proven to be a powerful radiopharmaceutical for PET imaging of neurodegenerative disorders such as Parkinson's disease (PD), its currently validated acquisition and quantification protocols are invasive and technically challenging in these populations due to the arterial sampling and relatively long scanning times. The objectives of this work were to evaluate a noninvasive (reference tissue) quantification method for [18F]SynVesT-1 in PD patients and to determine the minimum scan time necessary for accurate quantification. [18F]SynVesT-1 PET scans were acquired in 5 patients with PD and 3 healthy control subjects for 120 min with arterial blood sampling. Quantification was performed using the one-tissue compartment model (1TCM) with arterial input function, as well as with the simplified reference tissue model (SRTM) to estimate binding potential (BPND) using centrum semiovale (CS) as a reference region. The SRTM2 method was used with k2' fixed to either a sample average value (0.037 min-1) or a value estimated first through coupled fitting across regions for each participant. Direct SRTM estimation and the Logan reference region graphical method were also evaluated. There were no significant group differences in CS volume, radiotracer uptake, or efflux (ps > 0.47). Each fitting method produced BPND estimates in close agreement with those derived from the 1TCM (subject R2s > 0.98, bias < 10%), with no difference in bias between the control and PD groups. With SRTM2, BPND estimates from truncated scan data as short as 80 min produced values in excellent agreement with the data from the full 120 min scans (bias < 6%). While these are preliminary results from a small sample of patients with PD (n = 5), this work suggests that accurate synaptic density quantification may be performed without blood sampling and with scan time under 90 minutes. If further validated, these simplified procedures for [18F]SynVesT-1 PET quantification can facilitate its application as a clinical research imaging technology and allow for larger study samples and include a broader scope of patients including those with neurodegenerative diseases.
Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico por imagem , Cintilografia , Sistema Nervoso Central , Tomografia por Emissão de PósitronsRESUMO
Obsessive-compulsive disorder (OCD), anxiety disorders, and depressive disorders are highly comorbid, and each contribute to significant functional impairment for affected youth. Comorbid anxiety disorders in depressed youth have been associated with greater depressive symptom severity and impairment, but the impact of comorbid OCD in this population remains unclear. Accordingly, the present study examined the differential clinical characteristics of youth with depression and comorbid OCD relative to age/gender matched depressed youth with no such comorbidity and to those with depression and a comorbid (non-OCD) anxiety disorder. A sample of 797 youth and young adults ages 8-20 years who met diagnostic criteria for depression alone, depression with co-occurring OCD or any anxiety disorder were included in the present study. Rates of comorbid anxiety and OCD were very high (60.5% and 15.5%, respectively). Relative to youth with only depression, depressed youth with comorbid OCD or anxiety had greater severity of depression, suicidality, and overall impairment in social, physical, and emotional functioning. These results highlight the contribution of OCD or anxiety comorbidity in more complex clinical presentations for depressed youth.
RESUMO
Free-water imaging can predict and monitor dopamine system degeneration in people with Parkinson's disease. It can also enhance the sensitivity of traditional diffusion tensor imaging (DTI) metrics for indexing neurodegeneration. However, these tools are yet to be applied to investigate cholinergic system degeneration in Parkinson's disease, which involves both the pedunculopontine nucleus and cholinergic basal forebrain. Free-water imaging, free-water-corrected DTI and volumetry were used to extract structural metrics from the cholinergic basal forebrain and pedunculopontine nucleus in 99 people with Parkinson's disease and 46 age-matched controls. Cognitive ability was tracked over 4.5 years. Pearson's partial correlations revealed that free-water-corrected DTI metrics in the pedunculopontine nucleus were associated with performance on cognitive tasks that required participants to make rapid choices (behavioural flexibility). Volumetric, free-water content and DTI metrics in the cholinergic basal forebrain were elevated in a sub-group of people with Parkinson's disease with evidence of cognitive impairment, and linear mixed modelling revealed that these metrics were differently associated with current and future changes to cognition. Free water and free-water-corrected DTI can index cholinergic degeneration that could enable stratification of patients in clinical trials of cholinergic interventions for cognitive decline. In addition, degeneration of the pedunculopontine nucleus impairs behavioural flexibility in Parkinson's disease, which may explain this region's role in increased risk of falls.
Assuntos
Prosencéfalo Basal , Doença de Parkinson , Núcleo Tegmental Pedunculopontino , Humanos , Doença de Parkinson/complicações , Imagem de Tensor de Difusão , Prosencéfalo Basal/diagnóstico por imagem , Colinérgicos , Água , Neurônios ColinérgicosRESUMO
The dearth of child and adolescent mental health services (CAMHS) is a global problem. Integrating CAMHS in primary care has been offered as a solution. We sampled integrated care perspectives from colleagues around the world. Our findings include various models of integrated care namely: the stepped care model in Australia; shared care in the United Kingdom (UK) and Spain; school-based collaborative care in Qatar, Singapore and the state of Texas in the US; collaborative care in Canada, Brazil, US, and Uruguay; coordinated care in the US; and, developing collaborative care models in low-resource settings, like Kenya and Micronesia. These findings provide insights into training initiatives necessary to build CAMHS workforce capacity using integrated care models, each with the ultimate goal of improving access to care. Despite variations and progress in implementing integrated care models internationally, common challenges exist: funding within complex healthcare systems, limited training mechanisms, and geopolitical/policy issues. Supportive healthcare policy, robust training initiatives, ongoing quality improvement and measurement of outcomes across programs would provide data-driven support for the expansion of integrated care and ensure its sustainability.
Assuntos
Prestação Integrada de Cuidados de Saúde , Serviços de Saúde Mental , Adolescente , Adulto , Criança , Família , Humanos , Internacionalidade , Saúde MentalRESUMO
Striatal dopamine dysfunction is associated with the altered top-down modulation of pain processing. The dopamine D2-like receptor family is a potential substrate for such effects due to its primary expression in the striatum, but evidence for this is currently lacking. Here, we investigated the effect of pharmacologically manipulating striatal dopamine D2 receptor activity on the anticipation and perception of acute pain stimuli in humans. Participants received visual cues that induced either certain or uncertain anticipation of two pain intensity levels delivered via a CO2 laser. Rating of the pain intensity and unpleasantness was recorded. Brain activity was recorded with EEG and analysed via source localisation to investigate neural activity during the anticipation and receipt of pain. Participants completed the experiment under three conditions, control (Sodium Chloride), D2 receptor agonist (Cabergoline), and D2 receptor antagonist (Amisulpride), in a repeated-measures, triple-crossover, double-blind study. The antagonist reduced an individuals' ability to distinguish between low and high pain following uncertain anticipation. The EEG source localisation showed that the agonist and antagonist reduced neural activations in specific brain regions associated with the sensory integration of salient stimuli during the anticipation and receipt of pain. During anticipation, the agonist reduced activity in the right mid-temporal region and the right angular gyrus, whilst the antagonist reduced activity within the right postcentral, right mid-temporal, and right inferior parietal regions. In comparison to control, the antagonist reduced activity within the insula during the receipt of pain, a key structure involved in the integration of the sensory and affective aspects of pain. Pain sensitivity and unpleasantness were not changed by D2R modulation. Our results support the notion that D2 receptor neurotransmission has a role in the top-down modulation of pain.
RESUMO
ABSTRACT: The present study is aimed to identify the effect of gratitude as an adaptive regulating mechanism from suicidal ideation (SI) for veterans with mental illness (study 1) and student veterans with posttraumatic stress disorder (PTSD) symptoms (study 2) in the United States. Descriptive statistics and regression analyses were used to examine sociodemographic characteristics and relationships between gratitude and SI. Our study 1 consisted of 156 veterans with mental illness. The mean age for study 1 was 37.85. Our study 2 consisted of 232 student veterans with PTSD symptoms. The mean age for study 2 was 28.43. Higher gratitude scores in study 1 and study 2 were significantly associated with lower SI scores after adjusting for demographics and depression. This study partially supports the association between gratitude and SI in veterans with mental illness. Based on the results from this study, gratitude interventions may be effective in reducing SI when working with veterans with mental illness.
Assuntos
Emoções/fisiologia , Transtornos de Estresse Pós-Traumáticos , Estudantes , Ideação Suicida , Veteranos , Adulto , Feminino , Humanos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Resiliência Psicológica , Estados Unidos , Adulto JovemRESUMO
Runs of homozygosity (ROH) occur when offspring inherit haplotypes that are identical by descent from each parent. Length distributions of ROH are informative about population history; specifically, the probability of inbreeding mediated by mating system and/or population demography. Here, we investigated whether variation in killer whale (Orcinus orca) demographic history is reflected in genome-wide heterozygosity and ROH length distributions, using a global data set of 26 genomes representative of geographic and ecotypic variation in this species, and two F1 admixed individuals with Pacific-Atlantic parentage. We first reconstructed demographic history for each population as changes in effective population size through time using the pairwise sequential Markovian coalescent (PSMC) method. We found a subset of populations declined in effective population size during the Late Pleistocene, while others had more stable demography. Genomes inferred to have undergone ancestral declines in effective population size, were autozygous at hundreds of short ROH (<1 Mb), reflecting high background relatedness due to coalescence of haplotypes deep within the pedigree. In contrast, longer and therefore younger ROH (>1.5 Mb) were found in low latitude populations, and populations of known conservation concern. These include a Scottish killer whale, for which 37.8% of the autosomes were comprised of ROH >1.5 Mb in length. The fate of this population, in which only two adult males have been sighted in the past five years, and zero fecundity over the last two decades, may be inextricably linked to its demographic history and consequential inbreeding depression.
Assuntos
Orca , Animais , Genoma , Homozigoto , Endogamia , Masculino , Polimorfismo de Nucleotídeo Único , Densidade Demográfica , Orca/genéticaRESUMO
Cholinergic degeneration is a key feature of dementia in neurodegenerative conditions including Alzheimer's disease (AD) and Parkinson's disease (PD). Quantitative electro-encephalography (EEG) metrics are altered in both conditions from early stages, and recent research in people with Lewy body and AD dementia suggests these changes may be associated with atrophy in cholinergic basal forebrain nuclei (cBF). To determine if these relationships exist in predementia stages of neurodegenerative conditions, we studied resting-state EEG and in vivo cBF volumes in 31 people with PD (without dementia), 21 people with mild cognitive impairment (MCI), and 21 age-matched controls. People with PD showed increased power in slower frequencies and reduced alpha reactivity compared to controls. Volumes of cholinergic cell clusters corresponding to the medial septum and vertical and horizontal limb of the diagonal band, and the posterior nucleus basalis of Meynert, correlated positively with; alpha reactivity in people with PD (p< 0.01); and pre-alpha power in people with MCI (p< 0.05). These results suggest that alpha reactivity and pre-alpha power are related to changes in cBF volumes in MCI and PD without dementia.
Assuntos
Prosencéfalo Basal/patologia , Neurônios Colinérgicos/patologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Eletroencefalografia , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Idoso , Atrofia , Prosencéfalo Basal/citologia , Prosencéfalo Basal/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Doença de Parkinson/diagnósticoRESUMO
Essential E3 ubiquitin ligase HUWE1 (HECT, UBA, and WWE domain containing 1) regulates key factors, such as p53. Although mutations in HUWE1 cause heterogenous neurodevelopmental X-linked intellectual disabilities (XLIDs), the disease mechanisms common to these syndromes remain unknown. In this work, we identify p53 signaling as the central process altered in HUWE1-promoted XLID syndromes. By focusing on Juberg-Marsidi syndrome (JMS), one of the severest XLIDs, we show that increased p53 signaling results from p53 accumulation caused by HUWE1 p.G4310R destabilization. This further alters cell-cycle progression and proliferation in JMS cells. Modeling of JMS neurodevelopment reveals majorly impaired neural differentiation accompanied by increased p53 signaling. The neural differentiation defects can be successfully rescued by reducing p53 levels and restoring the expression of p53 target genes, in particular CDKN1A/p21. In summary, our findings suggest that increased p53 signaling underlies HUWE1-promoted syndromes and impairs XLID JMS neural differentiation.
Assuntos
Diferenciação Celular/genética , Deficiência Intelectual/genética , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/genética , Diferenciação Celular/fisiologia , Genes Ligados ao Cromossomo X/genética , Humanos , Mutação/genéticaRESUMO
Our group has recently shown that brain-penetrant ataxia telangiectasia-mutated (ATM) kinase inhibitors may have potential as novel therapeutics for the treatment of Huntington's disease (HD). However, the previously described pyranone-thioxanthenes (e.g., 4) failed to afford selectivity over a vacuolar protein sorting 34 (Vps34) kinase, an important kinase involved with autophagy. Given that impaired autophagy has been proposed as a pathogenic mechanism of neurodegenerative diseases such as HD, achieving selectivity over Vps34 became an important objective for our program. Here, we report the successful selectivity optimization of ATM over Vps34 by using X-ray crystal structures of a Vps34-ATM protein chimera where the Vps34 ATP-binding site was mutated to approximate that of an ATM kinase. The morpholino-pyridone and morpholino-pyrimidinone series that resulted as a consequence of this selectivity optimization process have high ATM potency and good oral bioavailability and have lower molecular weight, reduced lipophilicity, higher aqueous solubility, and greater synthetic tractability compared to the pyranone-thioxanthenes.
Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Piridonas/química , Pirimidinonas/química , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Sítios de Ligação , Encéfalo/metabolismo , Classe III de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Cristalografia por Raios X , Desenho de Fármacos , Meia-Vida , Humanos , Doença de Huntington/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Dinâmica Molecular , Morfolinos/química , Piridonas/metabolismo , Piridonas/uso terapêutico , Pirimidinonas/metabolismo , Pirimidinonas/uso terapêutico , Relação Estrutura-AtividadeRESUMO
Alkylating drugs are among the most often used chemotherapeutics. While cancer cells frequently develop resistance to alkylation treatments, detailed understanding of mechanisms that lead to the resistance is limited. Here, by using genome-wide CRISPR-Cas9 based screen, we identify transcriptional Mediator complex subunit 13 (MED13) as a novel modulator of alkylation response. The alkylation exposure causes significant MED13 downregulation, while complete loss of MED13 results in reduced apoptosis and resistance to alkylating agents. Transcriptome analysis identified cyclin D1 (CCND1) as one of the highly overexpressed genes in MED13 knock-out (KO) cells, characterized by shorter G1 phase. MED13 is able to bind to CCND1 regulatory elements thus influencing the expression. The resistance of MED13 KO cells is directly dependent on the cyclin D1 overexpression, and its down-regulation is sufficient to re-sensitize the cells to alkylating agents. We further demonstrate the therapeutic potential of MED13-mediated response, by applying combinatory treatment with CDK8/19 inhibitor Senexin A. Importantly, the treatment with Senexin A stabilizes MED13, and in combination with alkylating agents significantly reduces viability of cancer cells. In summary, our findings identify novel alkylation stress response mechanism dependent on MED13 and cyclin D1 that can serve as basis for development of innovative therapeutic strategies.
Assuntos
Antineoplásicos Alquilantes/farmacologia , Ciclina D1/genética , Complexo Mediador/fisiologia , Sistemas CRISPR-Cas , Linhagem Celular , Linhagem Celular Tumoral , Ciclina D1/metabolismo , Quinase 8 Dependente de Ciclina/antagonistas & inibidores , Quinases Ciclina-Dependentes/antagonistas & inibidores , Dano ao DNA , Resistencia a Medicamentos Antineoplásicos , Regulação da Expressão Gênica , Humanos , Complexo Mediador/metabolismo , Regulação para CimaRESUMO
Pediatric obesity and Attention Deficit Hyperactivity Disorder (ADHD) are rising health concerns in the United States, especially among Hispanic children and adolescents. Research on Hispanic children and adolescents indicates disproportionately higher prevalence rates of obesity in this community but scant data on ADHD prevalence rates. In contrast, a plethora of research studies across the general population examines the relationship between childhood obesity and ADHD. In addition, there is a lack of research that examines the role of ethnicity and sub-ethnic group correlations in ADHD, particularly in the Hispanic population. Existing studies in the general population indicate ADHD may be a risk factor for being overweight compared to normal controls. The objective of the present study is to examine the prevalence of obesity in children with ADHD compared to children in the general population in a predominately Hispanic sample on the US-Mexico border. A total of 7,270 pediatric medical records were evaluated. The retrospective analysis included Body Mass Index (BMI) and related health variables, and ethnicity and showed that children with ADHD are more likely to be underweight. In conclusion, no significant relationship existed between obesity and ADHD among Hispanic children on the US-Mexico Border, and instead we found the opposite correlation.