RESUMO
The Cell Division Cycle and Apoptosis Regulator (CCAR) protein family members have recently emerged as regulators of alternative splicing and transcription, as well as having other key physiological functions. For example, mammalian CCAR2/DBC1 forms a complex with the zinc factor protein ZNF326 to integrate alternative splicing with RNA polymerase II transcriptional elongation in AT-rich regions of the DNA. Additionally, Caenorhabditis elegans CCAR-1, a homolog to mammalian CCAR2, facilitates the alternative splicing of the perlecan unc-52 gene. However, much about the CCAR family's role in alternative splicing is unknown. Here, we have examined the role of CCAR-1 in genome-wide alternative splicing in Caenorhabditis elegans and have identified new alternative splicing targets of CCAR-1 using RNA sequencing. Also, we found that CCAR-1 interacts with the spliceosome factors UAF-1 and UAF-2 using mass spectrometry, and that knockdown of ccar-1 affects alternative splicing patterns, motility, and proteostasis of UAF-1 mutant worms. Collectively, we demonstrate the role of CCAR-1 in regulating global alternative splicing in C. elegans and in conjunction with UAF-1.
Assuntos
Processamento Alternativo , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Proteínas de Membrana , Ribonucleoproteínas , Animais , Sequência de Bases , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Splicing de RNA , Fator de Processamento U2AF/genética , Fator de Processamento U2AF/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismoRESUMO
AIMS: Iron deficiency is common in pulmonary hypertension, but its clinical significance and optimal definition remain unclear. METHODS AND RESULTS: Phenotypic data for 1028 patients enrolled in the Redefining Pulmonary Hypertension through Pulmonary Vascular Disease Phenomics study were analyzed. Iron deficiency was defined using the conventional heart failure definition and also based upon optimal cut-points associated with impaired peak oxygen consumption (peakVO2), 6-min walk test distance, and 36-Item Short Form Survey (SF-36) scores. The relationships between iron deficiency and cardiac and pulmonary vascular function and structure and outcomes were assessed. The heart failure definition of iron deficiency endorsed by pulmonary hypertension guidelines did not identify patients with reduced peakVO2, 6-min walk test, and SF-36 (P > 0.208 for all), but defining iron deficiency as transferrin saturation (TSAT) <21% did. Compared to those with TSAT ≥21%, patients with TSAT <21% demonstrated lower peakVO2 [absolute difference: -1.89 (-2.73 to -1.04) mL/kg/min], 6-min walk test distance [absolute difference: -34 (-51 to -17) m], and SF-36 physical component score [absolute difference: -2.5 (-1.3 to -3.8)] after adjusting for age, sex, and hemoglobin (all P < 0.001). Patients with a TSAT <21% had more right ventricular remodeling on cardiac magnetic resonance but similar pulmonary vascular resistance on catheterization. Transferrin saturation <21% was also associated with increased mortality risk (hazard ratio 1.63, 95% confidence interval 1.13-2.34; P = 0.009) after adjusting for sex, age, hemoglobin, and N-terminal pro-B-type natriuretic peptide. CONCLUSION: The definition of iron deficiency in the 2022 European Society of Cardiology (ESC)/European Respiratory Society (ERS) pulmonary hypertension guidelines does not identify patients with lower exercise capacity or functional status, while a definition of TSAT <21% identifies patients with lower exercise capacity, worse functional status, right heart remodeling, and adverse clinical outcomes.
Assuntos
Anemia Ferropriva , Insuficiência Cardíaca , Hipertensão Pulmonar , Deficiências de Ferro , Humanos , Anemia Ferropriva/complicações , Hemoglobinas , TransferrinasRESUMO
It has been challenging to target mutant KRAS (mKRAS) in colorectal cancer (CRC) and other malignancies. Recent efforts have focused on developing inhibitors blocking molecules essential for KRAS activity. In this regard, SOS1 inhibition has arisen as an attractive approach for mKRAS CRC given its essential role as a guanine nucleotide exchange factor for this GTPase. Here, we demonstrated the translational value of SOS1 blockade in mKRAS CRC. We used CRC patient-derived organoids (PDOs) as preclinical models to evaluate their sensitivity to SOS1 inhibitor BI3406. A combination of in silico analyses and wet lab techniques was utilized to define potential predictive markers for SOS1 sensitivity and potential mechanisms of resistance in CRC. RNA-seq analysis of CRC PDOs revealed two groups of CRC PDOs with differential sensitivities to SOS1 inhibitor BI3406. The resistant group was enriched in gene sets involving cholesterol homeostasis, epithelial-mesenchymal transition, and TNF-α/NFκB signaling. Expression analysis identified a significant correlation between SOS1 and SOS2 mRNA levels (Spearman's ρ 0.56, p < 0.001). SOS1/2 protein expression was universally present with heterogeneous patterns in CRC cells but only minimal to none in surrounding nonmalignant cells. Only SOS1 protein expression was associated with worse survival in patients with RAS/RAF mutant CRC (p = 0.04). We also found that SOS1/SOS2 protein expression ratio >1 by immunohistochemistry (p = 0.03) instead of KRAS mutation (p = 1) was a better predictive marker to BI3406 sensitivity of CRC PDOs, concordant with the significant positive correlation between SOS1/SOS2 protein expression ratio and SOS1 dependency. Finally, we showed that GTP-bound RAS level underwent rebound even in BI3406-sensitive PDOs with no change of KRAS downstream effector genes, thus suggesting upregulation of guanine nucleotide exchange factor as potential cellular adaptation mechanisms to SOS1 inhibition. Taken together, our results show that high SOS1/SOS2 protein expression ratio predicts sensitivity to SOS1 inhibition and support further clinical development of SOS1-targeting agents in CRC.
Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais , Proteína SOS1/genética , Proteína SOS1/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Mutação , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genéticaRESUMO
OBJECTIVE: To examine the relationship between headaches, naps, and nocturnal sleep in women with chronic migraine (CM) using micro-longitudinal data from diaries and actigraphy. METHODS: 20 women with CM and 20 age and sex-matched healthy controls (HC) completed self-report questionnaires, electronic diaries, and wrist actigraphy over a 4-week period. Between-group comparisons were conducted with naps (frequency and duration) as the primary variable of interest. Within-group analyses were conducted on the CM group using hierarchical linear mixed models to examine the temporal relationships between headache severity, sleep behaviors, and sleep parameters. The primary variables of interest were naps (number and duration) and nocturnal sleep efficiency (diary and actigraphy). RESULTS: The CM group reported significantly more days with naps (25.85%) compared to the HC group (9.03%) during the study period (p = .0025). Within-group analyses in CM revealed that greater headache severity was associated with longer nap duration (p = .0037) and longer nap duration was associated with lower sleep efficiency measured using diaries (p = .0014) and actigraphy (p < .0001). CONCLUSIONS: Napping is more frequent in CM than HC and nap duration in CM is associated with headache severity and nocturnal sleep disturbance. These findings provide initial support for the hypothesis that daytime napping is a behavioral coping strategy used in CM that could contribute to insomnia.
Assuntos
Transtornos de Enxaqueca , Distúrbios do Início e da Manutenção do Sono , Humanos , Feminino , Estudos Longitudinais , Sono , Distúrbios do Início e da Manutenção do Sono/complicações , Actigrafia , Transtornos de Enxaqueca/complicações , CefaleiaRESUMO
Phospholipases A2 (PLA2s) catalyze hydrolysis of the sn-2 substituent from glycerophospholipids to yield a free fatty acid (i.e., arachidonic acid), which can be metabolized to pro- or anti-inflammatory eicosanoids. Macrophages modulate inflammatory responses and are affected by Ca2+-independent phospholipase A2 (PLA2)ß (iPLA2ß). Here, we assessed the link between iPLA2ß-derived lipids (iDLs) and macrophage polarization. Macrophages from WT and KO (iPLA2ß-/-) mice were classically M1 pro-inflammatory phenotype activated or alternatively M2 anti-inflammatory phenotype activated, and eicosanoid production was determined by ultra-performance LC ESI-MS/MS. As a genotypic control, we performed similar analyses on macrophages from RIP.iPLA2ß.Tg mice with selective iPLA2ß overexpression in ß-cells. Compared with WT, generation of select pro-inflammatory prostaglandins (PGs) was lower in iPLA2ß-/- , and that of a specialized pro-resolving lipid mediator (SPM), resolvin D2, was higher; both changes are consistent with the M2 phenotype. Conversely, macrophages from RIP.iPLA2ß.Tg mice exhibited an opposite landscape, one associated with the M1 phenotype: namely, increased production of pro-inflammatory eicosanoids (6-keto PGF1α, PGE2, leukotriene B4) and decreased ability to generate resolvin D2. These changes were not linked with secretory PLA2 or cytosolic PLA2α or with leakage of the transgene. Thus, we report previously unidentified links between select iPLA2ß-derived eicosanoids, an SPM, and macrophage polarization. Importantly, our findings reveal for the first time that ß-cell iPLA2ß-derived signaling can predispose macrophage responses. These findings suggest that iDLs play critical roles in macrophage polarization, and we posit that they could be targeted therapeutically to counter inflammation-based disorders.
Assuntos
Cálcio/metabolismo , Eicosanoides/metabolismo , Fosfolipases A2 do Grupo IV/metabolismo , Macrófagos/metabolismo , Transdução de Sinais , Animais , Fosfolipases A2 do Grupo IV/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos TransgênicosRESUMO
RATIONALE: Activity levels in patients with pulmonary arterial hypertension (PAH) have correlated with surrogate markers of disease severity. It is not known whether physical activity measures are useful in monitoring patients with PAH. OBJECTIVES: This pilot study aimed to evaluate whether change in physical activity measured by an accelerometer correlates with changes in six-minute walk distance (6MWD), echocardiographic parameters, NT-proBNP, or health-related quality-of-life measures (HRQOL). METHODS: The study design was a prospective, observational study in subjects with prevalent PAH. Subjects wore a wrist-worn accelerometer (Fitbit Charge HR®) between two outpatient visits. Daily step count and activity levels were recorded, and the change over time was correlated with changes in 6MWD, echocardiographic parameters, HRQOL, and NT-proBNP. MEASUREMENTS AND MAIN RESULTS: 30 subjects were enrolled, of which 20 patients had adequate accelerometer data to be analyzed over the study duration. The mean duration of follow-up was 136.4 ( ± 47.3) days. The change in daily step count correlated with a change in 6MWD (r 0.43, p 0.05). Changes in duration spent in moderately active (r 0.52, p 0.02), lightly active (r 0.48, p 0.05), and sedentary activity levels (r - 0.54, p 0.02) correlated with a change in HRQOL. Changes in activity levels did not correlate with echocardiographic measures or NT-pro BNP. CONCLUSIONS: Changes in daily step count and time spent at fairly active, lightly active, and sedentary activity levels correlate with changes in 6MWD, and HRQOL in subjects with PAH suggesting that accelerometry may be a useful monitoring tool.
Assuntos
Actigrafia/instrumentação , Tolerância ao Exercício , Monitores de Aptidão Física , Hipertensão Arterial Pulmonar/diagnóstico , Caminhada , Biomarcadores/sangue , Ecocardiografia , Humanos , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Projetos Piloto , Valor Preditivo dos Testes , Estudos Prospectivos , Hipertensão Arterial Pulmonar/fisiopatologia , Qualidade de Vida , Comportamento Sedentário , Inquéritos e Questionários , Fatores de Tempo , Teste de CaminhadaRESUMO
The translational regulator cytosolic polyadenylation element-binding protein 2 (CPEB2) has two isoforms, CPEB2A and CPEB2B, derived by alternative splicing of RNA into a mature form that either includes or excludes exon 4. Previously, we reported that this splicing event is highly dysregulated in aggressive forms of breast cancers, which overexpress CPEB2B. The loss of CPEB2A with a concomitant increase in CPEB2B was also required for breast cancer cells to resist cell death because of detachment (anoikis resistance) and metastasize in vivo To examine the mechanism by which CPEB2 isoforms mediate opposing effects on cancer-related phenotypes, we used next generation sequencing of triple negative breast cancer cells in which the isoforms were specifically down-regulated. Down-regulation of the CPEB2B isoform inhibited pathways driving the epithelial-to-mesenchymal transition and hypoxic response, whereas down-regulation of the CPEB2A isoform did not have this effect. Examining key nodes of these pathways showed that CPEB2B induced the expression of regulatory DNA trans-factors (e.g. HIF1α and TWIST1). Specifically, CPEB2B functioned as a translational activator of TWIST1 and HIF1α. Functional studies showed that specific down-regulation of either HIF1α or TWIST1 inhibited the ability of CPEB2B to induce the acquisition of anoikis resistance and drive metastasis. Overall, this study demonstrates that CPEB2 alternative splicing is a major regulator of key cellular pathways linked to anoikis resistance and metastasis.
Assuntos
Processamento Alternativo , Anoikis , Neoplasias da Mama/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metástase Neoplásica , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismoRESUMO
OBJECTIVE: This observational pilot study examined objective circadian phase and sleep timing in chronic migraine (CM) and healthy controls (HC) and the impact of circadian factors on migraine frequency and severity. BACKGROUND: Sleep disturbance has been identified as a risk factor in the development and maintenance of CM but the biological mechanisms linking sleep and migraine remain largely theoretical. METHODS: Twenty women with CM and 20 age-matched HC completed a protocol that included a 7 day sleep assessment at home using wrist actigraphy followed by a circadian phase assessment using salivary melatonin. We compared CM vs HC on sleep parameters and circadian factors. Subsequently, we examined associations between dim-light melatonin onset (DLMO), the midpoint of the sleep episode, and the phase angle (time from DLMO to sleep midpoint) with the number of migraine days per month and the migraine disability assessment scale (MIDAS). RESULTS: CM and HC did not differ on measures of sleep or circadian phase. Within the CM group, more frequent migraine days per month was significantly correlated with DLMO (r = .49, P = .039) and later sleep episode (r = .47, P = .037). In addition, a greater phase angle (ie, circadian misalignment) was significantly correlated with more severe migraine-related disability (r = .48, P = .042). These relationships remained significant after adjusting for total sleep time. CONCLUSIONS: This pilot study revealed that circadian misalignment and delayed sleep timing are associated with higher migraine frequency and severity, which was not better accounted for by the amount of sleep. These findings support the plausibility and need for further investigation of a circadian pathway in the development and maintenance of chronic headaches. Specifically, circadian misalignment and delayed sleep timing could serve as an exacerbating factor in chronic migraines when combined with biological predispositions or environmental factors.
Assuntos
Transtornos Cronobiológicos/fisiopatologia , Transtornos de Enxaqueca/fisiopatologia , Actigrafia , Adolescente , Adulto , Transtornos Cronobiológicos/complicações , Transtornos Cronobiológicos/metabolismo , Feminino , Humanos , Transtornos de Enxaqueca/etiologia , Transtornos de Enxaqueca/metabolismo , Projetos Piloto , Adulto JovemRESUMO
Melanoma differentiation-associated gene 7 (MDA-7/IL-24) exhibits cytotoxic effects on tumor cells while sparing untransformed cells, and Bcl-x(L) is reported to efficiently block the induction of cell death by MDA-7/IL-24. The expression of Bcl-x(L) is regulated at the level of RNA splicing via alternative 5' splice site selection within exon 2 to produce either the pro-apoptotic Bcl-x(s) or the anti-apoptotic Bcl-x(L). Our laboratory previously reported that Bcl-x RNA splicing is dysregulated in a large percentage of human non-small cell lung cancer (NSCLC) tumors. Therefore, we investigated whether the alternative RNA splicing of Bcl-x pre-mRNA was modulated by MDA-7/IL-24, which would suggest that specific NSCLC tumors are valid targets for this cytokine therapy. Adenovirus-delivered MDA-7/IL-24 (Ad.mda-7) reduced the viability of NSCLC cells of varying oncogenotypes, which was preceded by a decrease in the ratio of Bcl-x(L)/Bcl-x(s) mRNA and Bcl-x(L) protein expression. Importantly, both the expression of Bcl-x(L) and the loss of cell viability were "rescued" in Ad.mda-7-treated cells incubated with Bcl-x(s) siRNA. In addition, NSCLC cells ectopically expressing Bcl-x(s) exhibited significantly reduced Bcl-x(L) expression, which was again restored by Bcl-x(s) siRNA, suggesting the existence of a novel mechanism by which Bcl-x(s) mRNA restrains the expression of Bcl-x(L). In additional mechanistic studies, inhibition of SRC and PKCδ completely ablated the ability of MDA-7/IL-24 to reduce the Bcl-x(L)/(s) mRNA ratio and cell viability. These findings show that Bcl-x(s) expression is an important mediator of MDA-7/IL-24-induced cytotoxicity requiring the SRC/PKCδ signaling axis in NSCLC cells.
Assuntos
Processamento Alternativo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Interleucinas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteína Quinase C-delta/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Estabilidade de RNA , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Transdução de Sinais , Proteína bcl-X/metabolismo , Células A549 , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Interleucinas/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteína Quinase C-delta/genética , Proteínas Proto-Oncogênicas pp60(c-src)/genética , RNA Mensageiro/genética , RNA Neoplásico/genética , Proteína bcl-X/genéticaRESUMO
Objective: To test the feasibility, acceptability, and effects of a home-based morning versus evening bright light treatment on function and pain sensitivity in women with fibromyalgia. Design: A single blind randomized study with two treatment arms: 6 days of a 1 hour morning light treatment or 6 days of a 1 hour evening light treatment. Function, pain sensitivity, and circadian timing were assessed before and after treatment. Setting: Participants slept at home, except for two nights in Sleep Center. Participants: Ten women meeting the American College of Rheumatology's diagnostic criteria for fibromyalgia, including normal blood test results. Methods: Self-reported function was assessed with the Fibromyalgia Impact Questionnaire (FIQ). Pain sensitivity was assessed using a heat stimulus that gave measures of threshold and tolerance. Circadian timing was assessed with the dim light melatonin onset. Results: Both morning and evening light treatments led to improvements in function and pain sensitivity. However, only the morning light treatment led to a clinically meaningful improvement in function (>14% reduction from baseline FIQ) and morning light significantly increased pain threshold more than evening light ( P < 0.05). Phase advances in circadian timing were associated with an increase in pain tolerance (r = 0.67, P < 0.05). Conclusions: Bright light treatment appears to be a feasible and acceptable adjunctive treatment to women with fibromyalgia. Those who undergo morning light treatment may show improvements in function and pain sensitivity. Advances in circadian timing may be one mechanism by which morning light improves pain sensitivity. Findings can inform the design of a randomized controlled trial.
Assuntos
Fibromialgia/terapia , Fototerapia/métodos , Adulto , Ritmo Circadiano/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Limiar da Dor/fisiologia , Projetos Piloto , Método Simples-Cego , Fatores de Tempo , Adulto JovemRESUMO
BACKGROUND: The number of cardiac cycles that need to be reviewed by echocardiography before a significant intrapulmonary shunt can be excluded remains unclear. METHODS: We retrospectively identified patients with cirrhosis who underwent technetium-99 m-labeled macroaggregated albumin scanning. The kinetics of bubble appearance after the injection of agitated saline during transthoracic echocardiograms were assessed in these patients. RESULTS: For the 64 eligible patients, the mean ± SD age was 56 ± 9 years. The median (IQR) shunt fraction by radionuclide scanning was 7.7% (2.8%-19.9%). Microbubbles were seen in the left atrium (LA) and left ventricle (LV) at a median (IQR) of 4 (2-5) and 4 (2-5) beats, respectively. The number of heart cycles before microbubbles appeared in the LA or LV was inversely associated with the nuclear scanning shunt fraction (R = -0.42, P = .001, R = -0.46, P < .001, respectively). If no microbubbles were detected by heart cycle 7, the shunt fraction was uniformly less than 3%. Patients with arterial oxygen <60 mm Hg, compared to ≥60 mm Hg, had earlier appearance of microbubbles in the left heart chambers (2.6 ± 1.9 vs 4.0 ± 2.3 beats, P = .046). CONCLUSIONS: In patients with advanced cirrhosis suspected of having hepatopulmonary syndrome, a greater shunt fraction during nuclear scanning was associated with more pronounced hypoxemia and a prompt and more intense appearance of microbubbles in the left-sided heart chambers. Patients with a shunt fraction above 3% have microbubbles in the LA or LV at some point during the first seven heart cycles.
Assuntos
Meios de Contraste/farmacocinética , Ecocardiografia/métodos , Cardiopatias/diagnóstico por imagem , Aumento da Imagem/métodos , Cirrose Hepática/complicações , Microbolhas , Cloreto de Sódio/farmacocinética , Feminino , Cardiopatias/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Despite the benefits of positive airway pressure (PAP) treatment, rates of adherence to treatment are suboptimal. This proof-of-concept study assessed the feasibility, acceptability, and clinical significance of an adaptive treatment strategy to improve adherence to PAP. All participants first completed a brief educational intervention. Those who did not show at least a 25% increase in PAP use were randomized to receive a second, more intensive intervention, either motivational enhancement treatment or self-management treatment. Results suggested adequate feasibility and acceptability. In addition, participants demonstrated significant increases in objective PAP use, improvements in sleep quality, and decreases in daytime sleepiness. This study represents a first step in the development and validation of an adaptive treatment strategy to improve PAP adherence.
Assuntos
Terapia Comportamental , Pressão Positiva Contínua nas Vias Aéreas/métodos , Motivação , Cooperação do Paciente , Apneia Obstrutiva do Sono/psicologia , Apneia Obstrutiva do Sono/terapia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fases do Sono/fisiologiaRESUMO
The purpose of this study was to examine the process of care in an interdisciplinary sleep clinic for patients with obstructive sleep apnea (OSA) and comorbid insomnia. A mixed-methods approach was used to examine clinical and patient-centered measures for 34 patients who received positive-airway pressure for OSA or cognitive-behavior therapy for insomnia. The results revealed baseline-to-follow-up improvements on several self-reported sleep parameters and measures of daytime functioning. Qualitative analyses from patient interviews revealed three themes: conceptual distinctions about each sleep disorder, importance of treating both sleep disorders, and preferences with regard to the sequence of treatment. These findings indicate that patients with OSA and comorbid insomnia encounter unique challenges. A dimensional approach to assessment and treatment is proposed for future research.
Assuntos
Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/terapia , Distúrbios do Início e da Manutenção do Sono/complicações , Distúrbios do Início e da Manutenção do Sono/terapia , Terapia Cognitivo-Comportamental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SonoRESUMO
Diabetes is a consequence of reduced ß-cell function and mass, due to ß-cell apoptosis. Endoplasmic reticulum (ER) stress is induced during ß-cell apoptosis due to various stimuli, and our work indicates that group VIA phospholipase A2ß (iPLA2ß) participates in this process. Delineation of underlying mechanism(s) reveals that ER stress reduces the anti-apoptotic Bcl-x(L) protein in INS-1 cells. The Bcl-x pre-mRNA undergoes alternative pre-mRNA splicing to generate Bcl-x(L) or Bcl-x(S) mature mRNA. We show that both thapsigargin-induced and spontaneous ER stress are associated with reductions in the ratio of Bcl-x(L)/Bcl-x(S) mRNA in INS-1 and islet ß-cells. However, chemical inactivation or knockdown of iPLA2ß augments the Bcl-x(L)/Bcl-x(S) ratio. Furthermore, the ratio is lower in islets from islet-specific RIP-iPLA2ß transgenic mice, whereas islets from global iPLA2ß(-/-) mice exhibit the opposite phenotype. In view of our earlier reports that iPLA2ß induces ceramide accumulation through neutral sphingomyelinase 2 and that ceramides shift the Bcl-x 5'-splice site (5'SS) selection in favor of Bcl-x(S), we investigated the potential link between Bcl-x splicing and the iPLA2ß/ceramide axis. Exogenous C6-ceramide did not alter Bcl-x 5'SS selection in INS-1 cells, and neutral sphingomyelinase 2 inactivation only partially prevented the ER stress-induced shift in Bcl-x splicing. In contrast, 5(S)-hydroxytetraenoic acid augmented the ratio of Bcl-x(L)/Bcl-x(S) by 15.5-fold. Taken together, these data indicate that ß-cell apoptosis is, in part, attributable to the modulation of 5'SS selection in the Bcl-x pre-mRNA by bioactive lipids modulated by iPLA2ß.
Assuntos
Apoptose/fisiologia , Ceramidas/metabolismo , Fosfolipases A2 do Grupo VI/metabolismo , Células Secretoras de Insulina/metabolismo , Sítios de Splice de RNA , Splicing de RNA/fisiologia , Proteína bcl-X/metabolismo , Animais , Ceramidas/genética , Estresse do Retículo Endoplasmático/fisiologia , Fosfolipases A2 do Grupo VI/genética , Humanos , Células Secretoras de Insulina/citologia , Camundongos , Camundongos Knockout , Ratos , Esfingomielina Fosfodiesterase/genética , Esfingomielina Fosfodiesterase/metabolismo , Proteína bcl-X/genéticaRESUMO
Triple negative breast cancer (TNBC) represents an anomalous subset of breast cancer with a greatly reduced (30%) 5-year survival rate. The enhanced mortality and morbidity of TNBC arises from the high metastatic rate, which requires the acquisition of AnR, a process whereby anchorage-dependent cells become resistant to cell death induced by detachment. In this study TNBC cell lines were selected for AnR, and these cell lines demonstrated dramatic enhancement in the formation of lung metastases as compared with parental cells. Genetic analysis of the AnR subclones versus parental cells via next generation sequencing and analysis of global alternative RNA splicing identified that the mRNA splicing of cytoplasmic polyadenylation element binding 2 (CPEB2), a translational regulator, was altered in AnR TNBC cells. Specifically, increased inclusion of exon 4 into the mature mRNA to produce the CPEB2B isoform was observed in AnR cell lines. Molecular manipulations of CPEB2 splice variants demonstrated a key role for this RNA splicing event in the resistance of cells to anoikis. Specifically, down-regulation of the CPEB2B isoform using siRNA re-sensitized the AnR cell lines to detachment-induced cell death. The ectopic expression of CPEB2B in parental TNBC cell lines induced AnR and dramatically increased metastatic potential. Importantly, alterations in the alternative splicing of CPEB2 were also observed in human TNBC and additional subtypes of human breast cancer tumors linked to a high metastatic rate. Our findings demonstrate that the regulation of CPEB2 mRNA splicing is a key mechanism in AnR and a driving force in TNBC metastasis.
Assuntos
Processamento Alternativo , Anoikis/fisiologia , Metástase Neoplásica , Proteínas de Ligação a RNA/fisiologia , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
The dim light melatonin onset (DLMO) assists with the diagnosis and treatment of circadian rhythm sleep disorders. Home DLMOs are attractive for cost savings and convenience, but can be confounded by home lighting and sample timing errors. We developed a home saliva collection kit with objective measures of light exposure and sample timing. We report on our first test of the kit in a clinical population. Thirty-two participants with delayed sleep phase disorder (DSPD; 17 women, aged 18-52 years) participated in two back-to-back home and laboratory phase assessments. Most participants (66%) received at least one 30-s epoch of light >50 lux during the home phase assessments, but for only 1.5% of the time. Most participants (56%) collected every saliva sample within 5 min of the scheduled time. Eighty-three per cent of home DLMOs were not affected by light or sampling errors. The home DLMOs occurred, on average, 10.2 min before the laboratory DLMOs, and were correlated highly with the laboratory DLMOs (r = 0.93, P < 0.001). These results indicate that home saliva sampling with objective measures of light exposure and sample timing, can assist in identifying accurate home DLMOs.
Assuntos
Ritmo Circadiano/efeitos da radiação , Habitação , Luz , Iluminação , Melatonina/metabolismo , Transtornos do Sono do Ritmo Circadiano/diagnóstico , Transtornos do Sono do Ritmo Circadiano/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Iluminação/efeitos adversos , Pessoa de Meia-Idade , Saliva/metabolismo , Saliva/efeitos da radiação , Fatores de Tempo , Adulto JovemRESUMO
Caspase-9 has two splice variants, pro-apoptotic caspase-9a and anti-apoptotic caspase-9b, which are regulated by RNA trans-factors associated with exon 3 of caspase-9 pre-mRNA (C9/E3). In this study, we identified hnRNP U as an RNA trans-factor associated with C9/E3. Down-regulation of hnRNP U led to a decrease in the caspase-9a/9b mRNA ratio, demonstrating a novel enhancing function. Importantly, hnRNP U bound specifically to C9/E3 at an RNA cis-element previously reported as the binding site for the splicing repressor, hnRNP L. Phosphorylated hnRNP L interfered with hnRNP U binding to C9/E3, and our results demonstrate the importance of the phosphoinositide 3-kinase/AKT pathway in modulating the association of hnRNP U to C9/E3. Taken together, these findings show that hnRNP U competes with hnRNP L for binding to C9/E3 to enhance the inclusion of the four-exon cassette, and this splice-enhancing function is blocked by the AKT pathway via phosphorylation of hnRNP L.
Assuntos
Caspase 9/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo L/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo U/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Processamento Alternativo , Sequência de Bases , Sítios de Ligação , Caspase 9/metabolismo , Linhagem Celular Tumoral , Éxons , Ribonucleoproteínas Nucleares Heterogêneas Grupo U/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Fosforilação , Ligação Proteica , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/fisiologia , Precursores de RNA/genética , Precursores de RNA/metabolismo , Splicing de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de SinaisRESUMO
OBJECTIVE: Sleep complaints are associated with adverse health consequences. We hypothesized that non-disabled older persons with more sleep complaints have an increased risk of developing disability. METHODS: Subjects included 908 older clergy participating in the Religious Order Study without clinical dementia, history of stroke, or Parkinson disease. At baseline, participants rated their difficulty falling asleep, frequency of nocturnal awakenings, sleep efficacy, and napping frequency, from which a summary dyssomnia measure was derived. Self-report assessment of disability included instrumental activities of daily living (IADLs), basic activities of daily living (ADLs), and Rosow-Breslau mobility disability at baseline and at annual evaluations. RESULTS: Mean follow-up was 9.6 (SD: 4.2) years. At baseline, more than 60% had one or more sleep complaints. In a series of Cox proportional hazards models controlling for age, sex, and education, a one-point higher dyssomnia score at baseline was associated with about 20% increased risk of IADL disability (hazard ratio: 1.20; 95% confidence interval [CI]: 1.04-1.39; χ(2)1 = 7.62; p <0.05), about 27% increased risk of ADL disability (hazard ratio: 1.27; 95% CI: 1.10-1.47; χ(2)1 = 12.15; p <0.01), and about 27% increased risk of mobility disability (hazard ratio: 1.27; 95% CI: 1.09-1.48; χ(2)1 = 11.04; p <0.01). These associations did not vary by age, sex, or education and remained significant after controlling for potential confounders including body mass index, chronic medical conditions, and several common medications. Controlling for depressive symptoms attenuated the association between sleep complaints and incident IADL and ADL disabilities but the association between sleep complaints and incident mobility disability remained significant. CONCLUSION: Non-disabled older adults with more sleep complaints have an increased risk of developing disability.
Assuntos
Envelhecimento/psicologia , Avaliação da Deficiência , Dissonias/epidemiologia , Atividades Cotidianas , Idoso , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Modelos de Riscos Proporcionais , Autorrelato , Estados Unidos/epidemiologiaRESUMO
Pancreatic Ductal Adenocarcinoma (PDAC) remains one of the most formidable challenges in oncology, characterized by its late detection and poor prognosis. Artificial intelligence (AI) and machine learning (ML) are emerging as pivotal tools in revolutionizing PDAC care across various dimensions. Consequently, many studies have focused on using AI to improve the standard of PDAC care. This review article attempts to consolidate the literature from the past five years to identify high-impact, novel, and meaningful studies focusing on their transformative potential in PDAC management. Our analysis spans a broad spectrum of applications, including but not limited to patient risk stratification, early detection, and prediction of treatment outcomes, thereby highlighting AI's potential role in enhancing the quality and precision of PDAC care. By categorizing the literature into discrete sections reflective of a patient's journey from screening and diagnosis through treatment and survivorship, this review offers a comprehensive examination of AI-driven methodologies in addressing the multifaceted challenges of PDAC. Each study is summarized by explaining the dataset, ML model, evaluation metrics, and impact the study has on improving PDAC-related outcomes. We also discuss prevailing obstacles and limitations inherent in the application of AI within the PDAC context, offering insightful perspectives on potential future directions and innovations.
RESUMO
Background: Blood lipids are dysregulated in pulmonary hypertension (PH). Lower high-density lipoproteins cholesterol (HDL-C) and low-density lipoproteins cholesterol (LDL-C) are associated with disease severity and death in PH. Right ventricle (RV) dysfunction and failure are the major determinants of morbidity and mortality in PH. This study aims to test the hypothesis that dyslipidemia is associated with RV dysfunction in PH. Methods: We enrolled healthy control subjects (n=12) and individuals with PH (n=30) (age: 18-65 years old). Clinical characteristics, echocardiogram, 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography (PET) scan, blood lipids, including total cholesterol (TC), triglycerides (TG), lipoproteins (LDL-C and HDL-C), and N-terminal pro-B type Natriuretic Peptide (NT-proBNP) were determined. Results: Individuals with PH had lower HDL-C [PH, 41±12; control, 56±16 mg/dL, p<0.01] and higher TG to HDL-C ratio [PH, 3.6±3.1; control, 2.2±2.2, p<0.01] as compared to controls. TC, TG, and LDL-C were similar between PH and controls. Lower TC and TG were associated with worse RV function measured by RV strain (R=-0.43, p=0.02 and R=-0.37, p=0.05 respectively), RV fractional area change (R=0.51, p<0.01 and R=0.48, p<0.01 respectively), RV end-systolic area (R=-0.63, p<0.001 and R=-0.48, p<0.01 respectively), RV end-diastolic area: R=-0.58, p<0.001 and R=-0.41, p=0.03 respectively), and RV glucose uptake by PET (R=-0.46, p=0.01 and R=-0.30, p=0.10 respectively). NT-proBNP was negatively correlated with TC (R=-0.61, p=0.01) and TG (R=-0.62, p<0.02) in PH. Conclusion: These findings confirm dyslipidemia is associated with worse right ventricular function in PH.