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OBJECTIVE: Accessible treatment options for avoidant/restrictive food intake disorder (ARFID) in children are limited. The current study sought to assess acceptability, feasibility, and preliminary efficacy of a brief, virtual intervention for ARFID in children ("ARFID-PTP"). METHOD: Families of children ages 5-12 with ARFID (n = 30) were randomized to immediate or waitlist treatment groups, with both groups ultimately receiving ARFID-PTP. ARFID-PTP consists of two, 2-h individual treatment sessions with an optional booster session at 4-week follow-up. Families completed acceptability and feasibility measures at end-of-treatment, as well as preliminary efficacy measures at 4-week, 3-month, and 6-month follow-up. RESULTS: Of 30 families who completed an intake session, 27 (90%) completed treatment. Families rated acceptability as high (MCEQ-C = 7.75). Treatment was feasible by participant retention. Exposure adherence was lower than expected, and booster session requests were higher than expected, indicating that achieving feasibility across measures may require treatment modifications. Regarding preliminary efficacy, children in the immediate treatment group had a decrease in ARFID symptoms compared to those on the waitlist. Overall, at 6-month follow-up linear mixed models showed participants had significantly reduced ARFID symptoms by presentation (p < 0.05) and in follow-up completers, children incorporated eight new foods on average. DISCUSSION: ARFID-PTP is acceptable and preliminarily efficacious. The protocol may benefit from modifications to increase feasibility; however, booster session content and treatment outcomes suggest a priori feasibility markers may not accurately capture the utility of ARFID-PTP. Further work should continue to examine the efficacy ARFID-PTP, particularly in diverse samples where treatment accessibility is urgently needed. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04913194.
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Cognitive and behavioral inflexibility are transdiagnostic maintaining mechanisms of varied psychopathologies, including eating disorders (ED). The Eating Disorder Flexibility Index (EDFLIX) is the only psychometrically validated self-report measure of general and ED-specific flexibility in the published literature. The EDFLIX was originally developed in Scandinavian adult clinical and healthy control samples but is increasingly used in its English version in other populations, including adolescent and nonclinical samples, raising questions about its validity and reliability in diverse groups. This study examined the factor structure of the previously published English EDFLIX in undergraduates (n = 578, 57.6 % female, 50.2 % White). Parallel and exploratory factor analysis suggested the EDFLIX may comprise two or three underlying factors. However, follow-up confirmatory factor analyses from nonclinical student and clinical ED-diagnosed (n = 69, 87.0 % female, 91.3 % White) samples did not support either model. Further, EDFLIX scores did not correlate with established neuropsychological measures of cognitive flexibility typically used in prior research on flexibility in EDs. Findings suggest the EDFLIX has poor psychometric properties in certain groups and may not capture underlying aspects of flexibility as previously proposed. Future research should explore alternative versions of the EDFLIX along with its psychometric properties across various samples.
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Transtornos da Alimentação e da Ingestão de Alimentos , Adulto , Humanos , Feminino , Adolescente , Masculino , Inquéritos e Questionários , Reprodutibilidade dos Testes , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Autorrelato , PsicometriaRESUMO
Research surrounding tumor boards has focused on patient outcomes and care coordination. Little is known about the patient experience with tumor boards. This survey examined aspects of the patient experience for patients presented at our multidisciplinary endocrine tumor board (ETB). A 15-item survey was distributed via the online patient portal to patients over the age of 18 whose case had been discussed at our ETB over an 18-month period. Descriptive statistics were reported, and a Fisher's exact test was used to examine relationships between variables. A total of 47 patients completed the survey (46%). A majority (72%) report their provider explained what the ETB is, and 77% report being informed their case would be discussed. Most patients were satisfied their case was being discussed (72%). A number of patients did report moderate or severe anxiety knowing their case was being discussed (15%). Sixty-four percent of patients report the ETB recommendations were clearly explained; however, satisfaction with the recommendations was slightly lower (53%). Despite the somewhat low satisfaction with the recommendations, 75% of patients felt more confident in their treatment plan knowing their case was discussed. Finally, if given the chance, 66% responded that they would have been interested in participating in their own ETB discussion. This study provides some insight into the patient experience surrounding tumor board discussions. Overall, patients are satisfied when their case is discussed at ETB. Patients can also experience anxiety about these discussions, and many patients desire to be present for their own discussions.
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Agouti-related peptide (AgRP/Agrp) within the hypothalamic arcuate nucleus (ARC) contributes to the control of energy balance, and dysregulated Agrp may contribute to metabolic adaptation during prolonged obesity. In mice, three isoforms of Agrp are encoded via distinct first exons. Agrp-A (ENSMUST00000005849.11) contributed 95% of total Agrp in mouse ARC, whereas Agrp-B (ENSMUST00000194654.2) dominated in placenta (73%). Conditional deletion of Klf4 from Agrp-expressing cells (Klf4Agrp-KO mice) reduced Agrp mRNA and increased energy expenditure but had no effects on food intake or the relative abundance of Agrp isoforms in the ARC. Chronic high-fat diet feeding masked these effects of Klf4 deletion, highlighting the context-dependent contribution of KLF4 to Agrp control. In the GT1-7 mouse hypothalamic cell culture model, which expresses all three isoforms of Agrp (including Agrp-C, ENSMUST00000194091.6), inhibition of extracellular signal-regulated kinase (ERK) simultaneously increased KLF4 binding to the Agrp promoter and stimulated Agrp expression. In addition, siRNA-mediated knockdown of Klf4 reduced expression of Agrp. We conclude that the expression of individual isoforms of Agrp in the mouse is dependent upon cell type and that KLF4 directly promotes the transcription of Agrp via a mechanism that is superseded during obesity.NEW & NOTEWORTHY In mice, three distinct isoforms of Agouti-related peptide are encoded via distinct first exons. In the arcuate nucleus of the hypothalamus, Krüppel-like factor 4 stimulates transcription of the dominant isoform in lean mice, but this mechanism is altered during diet-induced obesity.
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Proteína Relacionada com Agouti , Fator 4 Semelhante a Kruppel , Neurônios , Animais , Camundongos , Proteína Relacionada com Agouti/genética , Proteína Relacionada com Agouti/metabolismo , Hipotálamo/metabolismo , Neurônios/metabolismo , Obesidade/genética , Obesidade/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismoRESUMO
Syncytiotrophoblast stress is theorized to drive development of preeclampsia, but its molecular causes and consequences remain largely undefined. Multiple hormones implicated in preeclampsia signal via the Gαq cascade, leading to the hypothesis that excess Gαq signaling within the syncytiotrophoblast may contribute. First, we present data supporting increased Gαq signaling and antioxidant responses within villous and syncytiotrophoblast samples of human preeclamptic placenta. Second, Gαq was activated in mouse placenta using Cre-lox and DREADD methodologies. Syncytiotrophoblast-restricted Gαq activation caused hypertension, kidney damage, proteinuria, elevated circulating proinflammatory factors, decreased placental vascularization, diminished spiral artery diameter, and augmented responses to mitochondrial-derived superoxide. Administration of the mitochondrial-targeted antioxidant Mitoquinone attenuated maternal proteinuria, lowered circulating inflammatory and anti-angiogenic mediators, and maintained placental vascularization. These data demonstrate a causal relationship between syncytiotrophoblast stress and the development of preeclampsia and identify elevated Gαq signaling and mitochondrial reactive oxygen species as a cause of this stress.
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Pré-Eclâmpsia , Animais , Camundongos , Gravidez , Feminino , Humanos , Trofoblastos , Placenta , Antioxidantes/farmacologia , Proteínas de Ligação ao GTP , ProteinúriaRESUMO
The role of anti-Müllerian hormone (AMH), a potential marker of the hypothalamic-pituitary-ovarian axis, is not well established in adolescent females. Most studies use secondary sexual characteristics or chronological age as predictors for AMH. Skeletal maturity, an indicator of bone development, has not been examined to predict AMH. This study sought to examine patterns of change in AMH in relation to skeletal maturity. Demographics, anthropometry, hand-wrist radiographs, and cardiometabolic risk factors from 88 females (212 observations), between the ages of 8 to 18 years from the Fels Longitudinal Study were used in this study. AMH was analyzed using ELISA from stored frozen serum samples. Generalized linear mixed effect modeling was used. In the stepwise regression models, log-transformed AMH (AMHlog) was regressed on relative skeletal age as the skeletal maturity indicator (calculated as chronological age minus skeletal age) and adjusted for chronological age, adiposity, and cardiometabolic risk factors. Skeletal maturity significantly predicted lower AMHlog (ß= -0.073, SE=0.032, p=0.023). Glucose was significantly associated with decreases in AMHlog (ß= -0.008, SE=0.004, p=0.044). Chronological age modeled as a cubic function was not significant. AMH and skeletal maturity may provide correlated information on growth and pubertal status in adolescent females.
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Resting metabolic rate (RMR) adaptation occurs during obesity and is hypothesized to contribute to failed weight management. Angiotensin II (Ang-II) type 1 (AT1A) receptors in Agouti-related peptide (AgRP) neurons contribute to the integrative control of RMR, and deletion of AT1A from AgRP neurons causes RMR adaptation. Extracellular patch-clamp recordings identify distinct cellular responses of individual AgRP neurons from lean mice to Ang-II: no response, inhibition via AT1A and Gαi, or stimulation via Ang-II type 2 (AT2) receptors and Gαq. Following diet-induced obesity, a subset of Ang-II/AT1A-inhibited AgRP neurons undergo a spontaneous G-protein "signal switch," whereby AT1A stop inhibiting the cell via Gαi and instead begin stimulating the cell via Gαq. DREADD-mediated activation of Gαi, but not Gαq, in AT1A-expressing AgRP cells stimulates RMR in lean and obese mice. Thus, loss of AT1A-Gαi coupling within the AT1A-expressing AgRP neuron subtype represents a molecular mechanism contributing to RMR adaptation.
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Neurônios , Obesidade , Receptor Tipo 1 de Angiotensina , Animais , Camundongos , Proteína Relacionada com Agouti/metabolismo , Angiotensina II/metabolismo , Neurônios/metabolismo , Obesidade/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismoRESUMO
OBJECTIVE: Anorexia nervosa (AN) is associated with significant individual mental and physical suffering and public health burden and fewer than half of patients recover fully with current treatments. Comorbid exercise dependence (ExD) is common in AN and associated with significantly worse symptom severity and treatment outcomes. Research points to cognitive inflexibility as a prominent executive function inefficiency and transdiagnostic etiologic and maintaining mechanism linking AN and ExD. This study will evaluate the initial efficacy of adjunctive Cognitive Remediation Therapy (CRT), which has been shown to produce cognitive improvements in adults with AN, in targeting cognitive inflexibility in individuals with comorbid AN and ExD. As an exploratory aim, this study also addresses the current lack of quick and cost-effective assessments of cognitive flexibility by establishing the utility of two proposed biomarkers, heart rate variability and salivary oxytocin. METHOD: We will conduct a single-group, within-subjects trial of an established CRT protocol delivered remotely as an adjunct to inpatient or intensive outpatient treatment as usual (TAU) to adult patients (n = 42) with comorbid AN and ExD. Assessments, including self-report, neuropsychological, and biomarker measurements, will occur at three time points. RESULTS: We expect CRT to increase cognitive flexibility transdiagnostically and consequently, along with TAU, positively impact AN and ExD compulsivity and symptom severity, including weight gain. DISCUSSION: Findings will inform the development of more effective integrative interventions for AN and ExD targeting shared mechanisms and facilitate the routine assessment of cognitive flexibility as a transdiagnostic risk and maintaining factor across psychopathologies in clinical and research settings. PUBLIC SIGNIFICANCE: Patients with anorexia nervosa often engage in excessive exercise, leading to harmful outcomes, including increased suicidal behavior. This study examines the preliminary efficacy of an intervention that fosters flexible and holistic thinking in patients with problematic eating and exercise to, along with routine treatment, decrease harmful exercise symptoms. This study also examines new biological markers of the inflexible thinking style thought to be characteristic of anorexia nervosa and exercise dependence.
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Anorexia Nervosa , Terapia Cognitivo-Comportamental , Remediação Cognitiva , Adulto , Humanos , Terapia Cognitivo-Comportamental/métodos , Anorexia Nervosa/complicações , Anorexia Nervosa/terapia , Anorexia Nervosa/psicologia , Resultado do Tratamento , CogniçãoRESUMO
Canine cognitive dysfunction (CCD) syndrome is a well-recognized naturally occurring disease in aged dogs, with a remarkably similar disease course, both in its clinical presentation and neuropathological changes, as humans with Alzheimer's disease (AD). Similar to human AD patients this naturally occurring disease is found in the aging canine population however, there is little understanding of how the canine brain ages pathologically. It is well known that in neurodegenerative diseases, there is an increase in inflamed glial cells as well as an accumulation of hyperphosphorylation of tau (P-tau) and amyloid beta (Aß1-42). These pathologies increase neurotoxic signaling and eventual neuronal loss. We assessed these brain pathologies in aged canines and found an increase in the number of glial cells, both astrocytes and microglia, and the activation of astrocytes indicative of neuroinflammation. A rise in the aggregated protein Aß1-42 and hyperphosphorylated tau, at Threonine 181 and 217, in the cortical brain regions of aging canines. We then asked if any of these aged canines had CCD utilizing the only current diagnostic, owner questionnaires, verifying positive or severe CCD had pathologies of gliosis and accumulation of Aß1-42 like their aged, matched controls. However uniquely the CCD dogs had P-tau at T217. Therefore, this phosphorylation site of tau at threonine 217 may be a predictor for CCD.
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A common preclinical model of hypertension characterized by low circulating renin is the "deoxycorticosterone acetate (DOCA)-salt" model, which influences blood pressure and metabolism through mechanisms involving the angiotensin II type 1 receptor (AT1R) in the brain. More specifically, AT1R within Agouti-related peptide (AgRP) neurons of the arcuate nucleus of the hypothalamus (ARC) has been implicated in selected effects of DOCA-salt. In addition, microglia have been implicated in the cerebrovascular effects of DOCA-salt and angiotensin II. To characterize DOCA-salt effects upon the transcriptomes of individual cell types within the ARC, we used single-nucleus RNA sequencing (snRNAseq) to examine this region from male C57BL/6J mice that underwent sham or DOCA-salt treatment. Thirty-two unique primary cell type clusters were identified. Sub-clustering of neuropeptide-related clusters resulted in identification of three distinct AgRP subclusters. DOCA-salt treatment caused subtype-specific changes in gene expression patterns associated with AT1R and G protein signaling, neurotransmitter uptake, synapse functions, and hormone secretion. In addition, two primary cell type clusters were identified as resting versus activated microglia, and multiple distinct subtypes of activated microglia were suggested by sub-cluster analysis. While DOCA-salt had no overall effect on total microglial density within the ARC, DOCA-salt appeared to cause a redistribution of the relative abundance of activated microglia subtypes. These data provide novel insights into cell-specific molecular changes occurring within the ARC during DOCA-salt treatment, and prompt increased investigation of the physiological and pathophysiological significance of distinct subtypes of neuronal and glial cell types.
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Cancer cells exhibit elevated lipid synthesis. In breast and other cancer types, genes involved in lipid production are highly upregulated, but the mechanisms that control their expression remain poorly understood. Using integrated transcriptomic, lipidomic, and molecular studies, here we report that DAXX is a regulator of oncogenic lipogenesis. DAXX depletion attenuates, while its overexpression enhances, lipogenic gene expression, lipogenesis, and tumor growth. Mechanistically, DAXX interacts with SREBP1 and SREBP2 and activates SREBP-mediated transcription. DAXX associates with lipogenic gene promoters through SREBPs. Underscoring the critical roles for the DAXX-SREBP interaction for lipogenesis, SREBP2 knockdown attenuates tumor growth in cells with DAXX overexpression, and DAXX mutants unable to bind SREBP1/2 have weakened activity in promoting lipogenesis and tumor growth. Remarkably, a DAXX mutant deficient of SUMO-binding fails to activate SREBP1/2 and lipogenesis due to impaired SREBP binding and chromatin recruitment and is defective of stimulating tumorigenesis. Hence, DAXX's SUMO-binding activity is critical to oncogenic lipogenesis. Notably, a peptide corresponding to DAXX's C-terminal SUMO-interacting motif (SIM2) is cell-membrane permeable, disrupts the DAXX-SREBP1/2 interactions, and inhibits lipogenesis and tumor growth. These results establish DAXX as a regulator of lipogenesis and a potential therapeutic target for cancer therapy.
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Lipogênese , Neoplasias , Carcinogênese/genética , Transformação Celular Neoplásica , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Lipídeos , Lipogênese/genética , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , CamundongosRESUMO
OBJECTIVE: Disgust is an established mechanism driving restrictive eating behavior. Avoidant/restrictive food intake disorder (ARFID) is a restrictive eating disorder diagnosis characterized by extremely selective eating with three hypothesized presentations. It has been suggested that disgust is significantly associated with ARFID; however, there is limited empirical research to support this hypothesis. This study explores relationships between food-specific disgust, ARFID symptoms, and ARFID presentations. METHOD: Undergraduate students (n = 443, Mage = 19.14 years [SD = 1.25], 50.1% female, 52.7% White) completed a validated measure of food-specific disgust and an established self-report screening tool for the likely presence of ARFID and hypothesized ARFID presentations. RESULTS: Sixty-nine (14.5%) participants screened positively for the likely presence of ARFID. Food disgust did not differ between those who did and did not screen positively for ARFID (p > .05). Within the subsample of those screening positive for ARFID, disgust was not related to any of the three hypothesized presentations of ARFID (all p > .05). DISCUSSION: Our results did not show a significant association between disgust and positive ARFID screen or any of the hypothesized ARFID presentations. Importantly, these negative findings were obtained using validated screening tools for ARFID. Future research should seek to replicate these findings in clinical samples to further inform treatment. PUBLIC SIGNIFICANCE: Avoidant/restrictive food intake disorder (ARFID) is associated with significant medical and psychosocial complications, but the mechanism involved in its development and maintenance remain poorly understood. Findings from this study of college students screening positively for ARFID suggests that food disgust in not a key driver of ARFID symptoms. Exposure-based approaches, which are generally not thought to be effective in targeting disgust, may thus be appropriate in the treatment of ARFID.
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Transtorno Alimentar Restritivo Evitativo , Asco , Transtornos da Alimentação e da Ingestão de Alimentos , Humanos , Feminino , Adulto Jovem , Adulto , Masculino , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Autorrelato , Ingestão de Alimentos , Estudos RetrospectivosRESUMO
Strong ethnic identity is recognized as a protective factor against body image concern and eating pathology in Black women as they tend to hold cultural values in line with an acceptance of a variety of body shapes and sizes. Reinforcement of these cultural ideals may occur via same-race peer relationships. The current study examined the mediating role of same-race versus other-race peers in the relationship between ethnic identity and body appreciation in Black women. Participants were 139 Black undergraduate women (Mage = 18.94 years, MBMI = 25.33) who completed validated measures of ethnic identity and body appreciation and reported on the ethnic makeup of their friends. We conducted mediation analysis examining the role of same-race peers on the relationship between ethnic identity and body appreciation. Same-race peers mediated the relationship between ethnic identity and body appreciation, where having a greater percentage of friends increased both ethnic identity and body appreciation in Black women. The influence of same-race peers should be considered in the development of culturally informed prevention and intervention efforts for eating pathology in Black women.
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Histone 3 lysine27-to-methionine (H3-K27M) mutations most frequently occur in diffuse midline gliomas (DMGs) of the childhood pons but are also increasingly recognized in adults. Their potential heterogeneity at different ages and midline locations is vastly understudied. Here, through dissecting the single-cell transcriptomic, epigenomic and spatial architectures of a comprehensive cohort of patient H3-K27M DMGs, we delineate how age and anatomical location shape glioma cell-intrinsic and -extrinsic features in light of the shared driver mutation. We show that stem-like oligodendroglial precursor-like cells, present across all clinico-anatomical groups, display varying levels of maturation dependent on location. We reveal a previously underappreciated relationship between mesenchymal cancer cell states and age, linked to age-dependent differences in the immune microenvironment. Further, we resolve the spatial organization of H3-K27M DMG cell populations and identify a mitotic oligodendroglial-lineage niche. Collectively, our study provides a powerful framework for rational modeling and therapeutic interventions.
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Glioma , Humanos , Criança , Glioma/genética , Histonas/genética , Metionina , Mutação , Racemetionina , Microambiente Tumoral/genéticaRESUMO
Early into the COVID-19 pandemic, Miller & Blumstein (2020) outlined a theoretical research program (TRP) oriented around themes of contagion control and containment, legal amnesty, system leniency, nonenforcement, and tele-justice. Here, two and a half years later, these lingering themes are revisited to advocate for empirical research informing criminal justice system reform. The pandemic created rare natural experiment research conditions that enable unique and potentially valuable insights on necessitated innovations that may indicate future justice practices and policies. Given the sweeping effects of the shutdown, examples are numerous ranging from staffing analyses to estimate agencies' personnel needs to ensure that basic public safety functions can be met after early retirements and resignations from virus risk and anti-police sentiment, the use of virtual communication in various legal proceedings at arrest, incarceration, and release junctures, and, especially, the risks versus benefits of early release. In addition to better identifying who should be jailed pre-trial, prioritization of calls for service, triaging of court cases, and hygiene and sanitation issues within facilities are other important examples central to a COVID and crime TRP. Attending research could demonstrate the utility of normative operations and identify shortfalls to be addressed during anomic conditions prior to another shutdown or similar event and present, through comparison of innovative and traditional derived outcomes, system reform and improvement opportunities. By seizing upon rare data made possible by natural experimental COVID generated conditions, researchers can meaningfully investigate the ongoing applicability of justice system adaptations mandated by the pandemic in terms of effectiveness and efficiency toward the interrelated goals of evidence-based practice discovery and justice reform.
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Diffuse midline gliomas are uniformly fatal pediatric central nervous system cancers that are refractory to standard-of-care therapeutic modalities. The primary genetic drivers are a set of recurrent amino acid substitutions in genes encoding histone H3 (H3K27M), which are currently undruggable. These H3K27M oncohistones perturb normal chromatin architecture, resulting in an aberrant epigenetic landscape. To interrogate for epigenetic dependencies, we performed a CRISPR screen and show that patient-derived H3K27M-glioma neurospheres are dependent on core components of the mammalian BAF (SWI/SNF) chromatin remodeling complex. The BAF complex maintains glioma stem cells in a cycling, oligodendrocyte precursor cell-like state, in which genetic perturbation of the BAF catalytic subunit SMARCA4 (BRG1), as well as pharmacologic suppression, opposes proliferation, promotes progression of differentiation along the astrocytic lineage, and improves overall survival of patient-derived xenograft models. In summary, we demonstrate that therapeutic inhibition of the BAF complex has translational potential for children with H3K27M gliomas. SIGNIFICANCE: Epigenetic dysregulation is at the core of H3K27M-glioma tumorigenesis. Here, we identify the BRG1-BAF complex as a critical regulator of enhancer and transcription factor landscapes, which maintain H3K27M glioma in their progenitor state, precluding glial differentiation, and establish pharmacologic targeting of the BAF complex as a novel treatment strategy for pediatric H3K27M glioma. See related commentary by Beytagh and Weiss, p. 2730. See related article by Mo et al., p. 2906.
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Epigenoma , Glioma , Animais , Humanos , Mutação , Glioma/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células-Tronco Neoplásicas/metabolismo , Mamíferos/genética , Mamíferos/metabolismo , DNA Helicases/genética , Proteínas Nucleares/genéticaRESUMO
BACKGROUND: RGS (regulator of G protein signaling) family members catalyze the termination of G protein signaling cascades. Single nucleotide polymorphisms in the RGS2 gene in humans have been linked to hypertension, preeclampsia, and anxiety disorders. Mice deficient for Rgs2 (Rgs2Null) exhibit hypertension, anxiety, and altered adipose development and function. METHODS: To study cell-specific functions of RGS2, a novel gene-targeted mouse harboring a conditional allele for the Rgs2 gene (Rgs2Flox) was developed. These mice were bred with mice expressing Cre-recombinase via the Agouti-related peptide locus (Agrp-Cre) to cause deletion of Rgs2 from all cells expressing Agrp (Rgs2Agrp-KO), or a novel transgenic mouse expressing Cre-recombinase via the ANG (angiotensin) type 1A receptor (Agtr1a/ AT1A) promoter encoded in a bacterial artificial chromosome (BAC-AT1A-Cre) to delete Rgs2 in all Agtr1a-expressing cells (Rgs2AT1A-KO). RESULTS: Whereas Rgs2Flox, Rgs2Agrp-KO, and BAC-AT1A-Cre mice exhibited normal growth and survival, Rgs2AT1A-KO exhibited pre-weaning lethality. Relative to littermates, Rgs2Agrp-KO exhibited reduced fat gains when maintained on a high fat diet, associated with increased energy expenditure. Similarly, surviving adult Rgs2AT1A-KO mice also exhibited increased energy expenditure. Surprisingly, given the hypertensive phenotype previously reported for Rgs2Null mice and evidence supporting a role for RGS2 in terminating AT1A signaling in various cell types, Rgs2AT1A-KO mice exhibited normal blood pressure, ingestive behaviors, and renal functions, both before and after chronic infusion of ANG (490 ng/kg/min, sc). CONCLUSIONS: These results demonstrate the development of a novel mouse with conditional expression of Rgs2 and illustrate the role of Rgs2 within selected cell types for cardiometabolic control.
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Hipertensão , Proteínas RGS , Animais , Camundongos , Proteína Relacionada com Agouti , Hipertensão/genética , Camundongos Knockout , Camundongos Transgênicos , Receptor Tipo 1 de Angiotensina/genética , Recombinases , Proteínas RGS/genéticaRESUMO
BACKGROUND: GPCRs (G protein-coupled receptors) are implicated in blood pressure (BP) and fluid intake regulation. There is a developing concept that these effects are mediated by both canonical G protein signaling and noncanonical ß-arrestin mediated signaling, but the contributions of each remain largely unexplored. Here, we hypothesized that ß-arrestin contributes to fluid homeostasis and blood pressure (BP) regulation in deoxycorticosterone acetate (DOCA) salt hypertension, a prototypical model of salt-sensitive hypertension. METHODS: Global ß-arrestin1 (Arrb1) and ß-arrestin2 (Arrb2) knockout mice were employed to evaluate drinking behavior, and BP was evaluated in Arrb2-knockout mice. Age- and sex-matched C57BL/6 mice served as controls. We measured intake of water and different sodium chloride solutions and BP employing a 2-bottle choice paradigm with and without DOCA. RESULTS: Without DOCA (baseline), Arrb2-knockout mice exhibited a significant elevation in saline intake with no change in water intake. With DOCA treatment, Arrb2-knockout mice exhibited a significant increase in both saline and water intake. Although Arrb2-knockout mice exhibited hypernatremia at baseline conditions, we did not find significant changes in total body sodium stores or sodium palatability. In a separate cohort, BP was measured via telemetry in Arrb2-knockout and C57BL/6 mice with and without DOCA. Arrb2-knockout did not exhibit significant differences in BP before DOCA treatment when provided water alone, or when provided a choice of water and saline. However, Arrb2-knockout exhibited an increased pressor response to DOCA-salt. CONCLUSIONS: These findings suggest that in salt-sensitive hypertension, ARRB2, but not ARRB1 (ß-arrestin 1), might counterbalance the canonical signaling of GPCRs.
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Acetato de Desoxicorticosterona , Hipertensão , Animais , Camundongos , Pressão Sanguínea/fisiologia , beta-Arrestina 2/genética , Camundongos Endogâmicos C57BL , Hipertensão/genética , Cloreto de Sódio na Dieta/farmacologia , Cloreto de Sódio/farmacologia , Sódio , beta-Arrestinas , Camundongos Knockout , Homeostase , Água , DesoxicorticosteronaRESUMO
Inheritance of the SLICK1 allele of the prolactin receptor gene improves thermotolerance of lactating Holstein cows under humid heat stress conditions. The aim of this study was to investigate whether pre- and postweaning Holstein heifers carrying the SLICK1 allele would show physiological responses indicative of higher tolerance to heat stress in high- and low-humidity climates. A total of 101 heifer calves of two age groups heterozygous for the SLICK1 allele and 103 wild-type half-siblings were evaluated during July 2020 in 3 dairy farms in central California and 2 in south Florida. Dry bulb temperature and relative humidity data were recorded during evaluation and used to calculate the temperature-humidity index (THI). Physiological measurements were obtained between 1600 and 1900 h in California, and 1200 and 1400 h in Florida and included rectal temperature, respiration rate, skin temperature, and sweating rate. Data were analyzed via Generalized Linear Mixed Models including the main effects of genotype, state, group, sire, farm within state, and interactions, with THI included as a covariate. The correlations between THI and dependent variables were analyzed via linear regression. The average 24-h THI was higher in Florida compared with California (90 vs. 72, respectively); the main driver of the higher THI in Florida was the high relative humidity (average 85.6% in Florida vs. 36.7% in California). In Florida, the rectal temperature of slick calves was 0.4°C lower than non-slick calves (39.5 ± 0.1 vs 39.9 ± 0.1°C); no differences were detected between slick and non-slick calves in California. Regardless of genotype, heifer calves in Florida had higher respiration rate, higher rectal and skin temperatures, and lower sweating rate than in California. This study is the first to evaluate physiological responses of calves carrying the SLICK1 allele under heat stress conditions in different climates. Our findings demonstrate that the presence of this allele is associated with lower rectal temperatures in pre- and post-weaning Holstein females. According to the physiological parameters evaluated, calves raised in Florida appeared to be under more severe heat stress; in those conditions, the SLICK1 allele was advantageous to confer thermotolerance as evidenced by lower rectal temperature in slick animals.
Assuntos
Doenças dos Bovinos , Transtornos de Estresse por Calor , Bovinos , Animais , Feminino , Lactação/fisiologia , Fazendas , Alelos , Receptores da Prolactina , Florida , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico , Umidade , Temperatura Alta , CaliforniaRESUMO
STUDY QUESTION: Is reproductive aging in granulosa cells associated with markers of ovarian reserve? SUMMARY ANSWER: Age acceleration was associated with anti-Mullerian hormone (AMH) levels, antral follicle count (AFC), oocyte yield and maturity, and the number of successfully fertilized embryos. WHAT IS KNOWN ALREADY: The rate of reproductive aging varies among women of the same age. DNA methylation can be used to predict epigenetic age in a variety of tissues. STUDY DESIGN, SIZE, DURATION: This was a cross-sectional study of 70 women at the time of oocyte retrieval. PARTICIPANTS/MATERIALS, SETTING, METHODS: The 70 participants were recruited for this study at an academic medical center and they provided follicular fluid samples at the time of oocyte retrieval. Granulosa cells were isolated and assessed on the MethylationEPIC array. Linear regression was used to evaluate the associations between DNA methylation-based age predictions from granulosa cells and chronological age. Age acceleration was calculated as the residual of regressing DNA methylation-based age on chronological age. Linear regressions were used to determine the associations between age acceleration and markers of ovarian reserve and IVF cycle outcomes. MAIN RESULTS AND THE ROLE OF CHANCE: Participants were a mean of 36.7 ± 3.9 years old. In regards to race, 54% were white, 19% were African American and 27% were of another background. Age acceleration was normally distributed and not associated with chronological age. Age acceleration was negatively associated with AMH levels (t = -3.1, P = 0.003) and AFC (t = -4.0, P = 0.0001), such that women with a higher age acceleration had a lower ovarian reserve. Age acceleration was also negatively correlated with the total number of oocytes retrieved (t = -3.9, P = 0.0002), the number of mature oocytes (t = -3.8, P = 0.0003) and the number of fertilized oocytes or two-pronuclear oocytes (t = -2.8, P = 0.008) in the main analysis. LIMITATIONS, REASONS FOR CAUTION: This study used pooled follicular fluid, which does not allow for the investigation of individual follicles. Infertility patients may also be different from the general population, but, as we used granulosa cells, the participants had to be from an IVF population. WIDER IMPLICATIONS OF THE FINDINGS: This study demonstrated that epigenetic age and age acceleration can be calculated from granulosa cells collected at the time of oocyte retrieval. GrimAge most strongly predicted chronological age, and GrimAge acceleration was associated with baseline and cycle characteristics as well as cycle outcomes, which indicates its potential clinical relevance in evaluating both oocyte quantity and quality. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Institutes of Health (UL1TR002378) and the Building Interdisciplinary Research Careers in Women's Health Program (K12HD085850) to A.K.K. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The funding source had no role in any aspect of this study. J.B.S. serves as Vice Chair for the American Society for Reproductive Medicine Education Committee, is a Medical Committee Advisor for the Jewish Fertility Foundation and works with Jscreen. J.B.S. has received funding from Georgia Clinical Translational Research Alliance. H.S.H., J.B.S. and A.K.S. have received NIH funding for other projects. A.K.K., S.A.G., S.G., Q.S.K., L.J.M. and W.S. have no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.