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2.
J Physiol ; 602(19): 4729-4752, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39216087

RESUMO

Mechanical ventilation (MV) is used to support ventilation and pulmonary gas exchange in patients during critical illness and surgery. Although MV is a life-saving intervention for patients in respiratory failure, an unintended side-effect of MV is the rapid development of diaphragmatic atrophy and contractile dysfunction. This MV-induced diaphragmatic weakness is labelled as 'ventilator-induced diaphragm dysfunction' (VIDD). VIDD is an important clinical problem because diaphragmatic weakness is a risk factor for the failure to wean patients from MV. Indeed, the inability to remove patients from ventilator support results in prolonged hospitalization and increased morbidity and mortality. The pathogenesis of VIDD has been extensively investigated, revealing that increased mitochondrial production of reactive oxygen species within diaphragm muscle fibres promotes a cascade of redox-regulated signalling events leading to both accelerated proteolysis and depressed protein synthesis. Together, these events promote the rapid development of diaphragmatic atrophy and contractile dysfunction. This review highlights the MV-induced changes in the structure/function of diaphragm muscle and discusses the cell-signalling mechanisms responsible for the pathogenesis of VIDD. This report concludes with a discussion of potential therapeutic opportunities to prevent VIDD and suggestions for future research in this exciting field.


Assuntos
Diafragma , Respiração Artificial , Diafragma/fisiopatologia , Humanos , Animais , Respiração Artificial/efeitos adversos , Debilidade Muscular/fisiopatologia , Debilidade Muscular/etiologia , Debilidade Muscular/metabolismo , Atrofia Muscular/etiologia , Atrofia Muscular/fisiopatologia , Atrofia Muscular/metabolismo , Contração Muscular/fisiologia
3.
Free Radic Biol Med ; 224: 470-478, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39181477

RESUMO

Following the discovery that exercise increases the production of reactive oxygen species in contracting skeletal muscles, evidence quickly emerged that endurance exercise training increases the abundance of key antioxidant enzymes in the trained muscles. Since these early observations, knowledge about the impact that regular exercise has on skeletal muscle antioxidant capacity has increased significantly. Importantly, in recent years, our understanding of the cell signaling pathways responsible for this exercise-induced increase in antioxidant enzymes has expanded exponentially. Therefore, the goals of this review are: 1) summarize our knowledge about the influence that exercise training has on the abundance of key antioxidant enzymes in skeletal muscles; and 2) to provide a state-of-the-art review of the nuclear factor erythroid 2-related factor (Nrf2) signaling pathway that is responsible for many of the exercise-induced changes in muscle antioxidant capacity. We begin with a discussion of the sources of reactive oxygen species in contracting muscles and then examine the exercise-induced changes in the antioxidant enzymes that eliminate both superoxide radicals and hydrogen peroxide in muscle fibers. We conclude with a discussion of the advances in our understanding of the exercise-induced control of the Nrf2 signaling pathway that is responsible for the expression of numerous antioxidant proteins. In hopes of stimulating future research, we also identify gaps in our knowledge about the signaling pathways responsible for the exercise-induced increases in muscle antioxidant enzymes.

5.
Headache ; 64(8): 912-930, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-39149968

RESUMO

OBJECTIVE: To identify and disseminate research priorities for the headache field that should be areas of research focus during the next 10 years. BACKGROUND: Establishing research priorities helps focus and synergize the work of headache investigators, allowing them to reach the most important research goals more efficiently and completely. METHODS: The Headache Research Priorities organizing and executive committees and working group chairs led a multistakeholder and international group of experts to develop headache research priorities. The research priorities were developed and reviewed by clinicians, scientists, people with headache, representatives from headache organizations, health-care industry representatives, and the public. Priorities were revised and finalized after receiving feedback from members of the research priorities working groups and after a public comment period. RESULTS: Twenty-five research priorities across eight categories were identified: human models, animal models, pathophysiology, diagnosis and management, treatment, inequities and disparities, research workforce development, and quality of life. The priorities address research models and methods, development and optimization of outcome measures and endpoints, pain and non-pain symptoms of primary and secondary headaches, investigations into mechanisms underlying headache attacks and chronification of headache disorders, treatment optimization, research workforce recruitment, development, expansion, and support, and inequities and disparities in the headache field. The priorities are focused enough that they help to guide headache research and broad enough that they are widely applicable to multiple headache types and various research methods. CONCLUSIONS: These research priorities serve as guidance for headache investigators when planning their research studies and as benchmarks by which the headache field can measure its progress over time. These priorities will need updating as research goals are met and new priorities arise.


Assuntos
Pesquisa Biomédica , Cefaleia , Sociedades Médicas , Humanos , Cefaleia/terapia , Pesquisa , Estados Unidos , Objetivos , Animais
7.
Sci Rep ; 14(1): 13227, 2024 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-38851782

RESUMO

There are hundreds of genes typically overexpressed in breast cancer cells and it's often assumed that their overexpression contributes to cancer progression. However, the precise proportion of these overexpressed genes contributing to tumorigenicity remains unclear. To address this gap, we undertook a comprehensive screening of a diverse set of seventy-two genes overexpressed in breast cancer. This systematic screening evaluated their potential for inducing malignant transformation and, concurrently, assessed their impact on breast cancer cell proliferation and viability. Select genes including ALDH3B1, CEACAM5, IL8, PYGO2, and WWTR1, exhibited pronounced activity in promoting tumor formation and establishing gene dependencies critical for tumorigenicity. Subsequent investigations revealed that CEACAM5 overexpression triggered the activation of signaling pathways involving ß-catenin, Cdk4, and mTOR. Additionally, it conferred a growth advantage independent of exogenous insulin in defined medium and facilitated spheroid expansion by inducing multiple layers of epithelial cells while preserving a hollow lumen. Furthermore, the silencing of CEACAM5 expression synergized with tamoxifen-induced growth inhibition in breast cancer cells. These findings underscore the potential of screening overexpressed genes for both oncogenic drivers and tumor dependencies to expand the repertoire of therapeutic targets for breast cancer treatment.


Assuntos
Neoplasias da Mama , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Feminino , Proliferação de Células/genética , Linhagem Celular Tumoral , Transdução de Sinais , Oncogenes , beta Catenina/metabolismo , beta Catenina/genética , Tamoxifeno/farmacologia , Animais , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Transformação Celular Neoplásica/genética
8.
J Sport Health Sci ; 13(6): 780-792, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38719184

RESUMO

The discovery that contracting skeletal muscle generates reactive oxygen species (ROS) was first reported over 40 years ago. The prevailing view in the 1980s was that exercise-induced ROS production promotes oxidation of proteins and lipids resulting in muscle damage. However, a paradigm shift occurred in the 1990s as growing research revealed that ROS are signaling molecules, capable of activating transcriptional activators/coactivators and promoting exercise-induced muscle adaptation. Growing evidence supports the notion that reduction-oxidation (redox) signaling pathways play an important role in the muscle remodeling that occurs in response to endurance exercise training. This review examines the specific role that redox signaling plays in this endurance exercise-induced skeletal muscle adaptation. We begin with a discussion of the primary sites of ROS production in contracting muscle fibers followed by a summary of the antioxidant enzymes involved in the regulation of ROS levels in the cell. We then discuss which redox-sensitive signaling pathways promote endurance exercise-induced muscle adaptation and debate the strength of the evidence supporting the notion that redox signaling plays an essential role in muscle adaptation to endurance exercise training. In hopes of stimulating future research, we highlight several important unanswered questions in this field.


Assuntos
Adaptação Fisiológica , Exercício Físico , Músculo Esquelético , Oxirredução , Resistência Física , Espécies Reativas de Oxigênio , Transdução de Sinais , Espécies Reativas de Oxigênio/metabolismo , Humanos , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Adaptação Fisiológica/fisiologia , Resistência Física/fisiologia , Transdução de Sinais/fisiologia , Exercício Físico/fisiologia , Contração Muscular/fisiologia , Animais , Antioxidantes/metabolismo
9.
Cancer Discov ; 14(7): 1302-1323, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38683161

RESUMO

The tumor microenvironment (TME) profoundly influences tumorigenesis, with gene expression in the breast TME capable of predicting clinical outcomes. The TME is complex and includes distinct cancer-associated fibroblast (CAF) subtypes whose contribution to tumorigenesis remains unclear. Here, we identify a subset of myofibroblast CAFs (myCAF) that are senescent (senCAF) in mouse and human breast tumors. Utilizing the MMTV-PyMT;INK-ATTAC (INK) mouse model, we found that senCAF-secreted extracellular matrix specifically limits natural killer (NK) cell cytotoxicity to promote tumor growth. Genetic or pharmacologic senCAF elimination unleashes NK cell killing, restricting tumor growth. Finally, we show that senCAFs are present in HER2+, ER+, and triple-negative breast cancer and in ductal carcinoma in situ (DCIS) where they predict tumor recurrence. Together, these findings demonstrate that senCAFs are potently tumor promoting and raise the possibility that targeting them by senolytic therapy could restrain breast cancer development. Significance: senCAFs limit NK cell-mediated killing, thereby contributing to breast cancer progression. Thus, targeting senCAFs could be a clinically viable approach to limit tumor progression. See related article by Belle et al., p. 1324.


Assuntos
Neoplasias da Mama , Fibroblastos Associados a Câncer , Progressão da Doença , Microambiente Tumoral , Animais , Feminino , Camundongos , Humanos , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/imunologia , Microambiente Tumoral/imunologia , Células Matadoras Naturais/imunologia , Senescência Celular/imunologia
10.
Neurol Clin Pract ; 14(3): e200294, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38682006

RESUMO

Background and Objectives: This cross-sectional observational study retrospectively examined clinical data collected from adolescents and young adults (AYAs) seeking care in a specialty headache clinic. We characterized participants' headache characteristics and psychological functioning and examined the association between self-reported anxiety and depressive symptoms and headache frequency, severity, and disability. Methods: During their clinic visit, AYAs (M age = 18.36; range = 14-32, 79.5% female) completed an intake questionnaire and reported about their headache characteristics (i.e., frequency, severity, and duration of symptoms in months), mental health history (i.e., previous diagnosis of an anxiety or depressive disorder), and utilization of emergency department (ED) services for migraine. AYAs also completed psychometrically validated screening tools for anxiety and depressive symptoms (i.e., the GAD-7 and PHQ-9). We computed descriptive statistics and examined associations among scores on psychological measures and headache characteristics, including migraine-related disability. We also tested whether individuals with clinically elevated GAD-7 and PHQ-9 scores had higher levels of disability relative to those with fewer/subclinical levels of anxiety and depressive symptoms. Results: Participants (N = 283) reported more than 19 headache days per month on average, with more than 90% describing their average headache intensity as moderate or severe. Nearly half of AYAs reported severe headache-related disability. Approximately one-quarter of AYAs reported a previous diagnosis anxiety or depressive disorder diagnosis, and more than one-third scored above clinical cutoffs on the PHQ-9 and GAD-7. Higher scores on both psychological screening instruments were associated with greater headache frequency. More than 10% of patients endorsed current suicidal ideation; this was not related to headache-related disability. Participants reported a high degree of ED utilization for headache; these rates were unrelated to endorsement of psychological comorbidities. Discussion: In this sample of AYAs, headache characteristics were generally unrelated to scores on measures on psychological functioning. However, the observed rates of clinically elevated anxiety/depressive symptoms and suicidality in this sample of AYAs underscore the importance of screening for psychological comorbidities in neurology clinics that serve this age group, irrespective of self-reported disability. Results also emphasize the need to expand access to behavioral health services for AYAs with headache disorders and the importance of incorporating a biopsychosocial perspective to the transition of health care from pediatrics to adult neurology practice.

12.
Cancers (Basel) ; 16(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38473364

RESUMO

Drug resistance can evolve from a subpopulation of cancer cells that initially survive drug treatment and then gradually form a pool of drug-tolerant cells. Several studies have pinpointed the activation of a specific bypass pathway that appears to provide the critical therapeutic target for preventing drug tolerance. Here, we take a systems-biology approach, using proteomics and genomics to examine the development of drug tolerance to EGFR inhibitors in EGFR-mutant lung adenocarcinoma cells and BRAF inhibitors in BRAF-mutant melanoma cells. We found that there are numerous alternative mitogenic pathways that become activated in both cases, including YAP, STAT3, IGFR1, and phospholipase C (PLC)/protein kinase C (PKC) pathways. Our results suggest that an effective therapeutic strategy to prevent drug tolerance will need to take multiple alternative mitogenic pathways into account rather than focusing on one specific pathway.

14.
Neurol Clin Pract ; 13(5): e200188, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37840826

RESUMO

Background and Objectives: The prevalence of generalized joint hypermobility (GJH) is 5-65% in children and adolescents. The hypothesis of this study was to see whether there is an association between headache characteristics and GJH in children and adolescents with migraine. Methods: We performed a primary retrospective case-control analysis of an established database of patients with headache aged 5-17 years. Results: We included 5435 participants. Approximately 31.6% of participants (1,719/5,435) were diagnosed with GJH (Beighton score ≥ 6). Nausea (73.1% vs 67.5%, χ2 with 1 degree of freedom = 17.0, p < 0.0001), phonophobia (87.3% vs 78.8%, χ2 with 1 degree of freedom = 18.0, p < 0.0001), and the PedMIDAS score (48.2 ± 52.5, 95% CI 45.7-50.6 vs 41.6 ± 51.2, 95% CI 40.0-43.3, effect size = 0.13, p < 0.0001) were noted to be more severe in participants with GJH than those without GJH. Discussion: Youths with GJH and migraine were noted to have more severe migraine characteristics.

15.
Headache ; 63(9): 1330-1331, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37795652
16.
Nat Commun ; 14(1): 5226, 2023 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-37633924

RESUMO

Bulk analyses of pancreatic ductal adenocarcinoma (PDAC) samples are complicated by the tumor microenvironment (TME), i.e. signals from fibroblasts, endocrine, exocrine, and immune cells. Despite this, we and others have established tumor and stroma subtypes with prognostic significance. However, understanding of underlying signals driving distinct immune and stromal landscapes is still incomplete. Here we integrate 92 single cell RNA-seq samples from seven independent studies to build a reproducible PDAC atlas with a focus on tumor-TME interdependence. Patients with activated stroma are synonymous with higher myofibroblastic and immunogenic fibroblasts, and furthermore show increased M2-like macrophages and regulatory T-cells. Contrastingly, patients with 'normal' stroma show M1-like recruitment, elevated effector and exhausted T-cells. To aid interoperability of future studies, we provide a pretrained cell type classifier and an atlas of subtype-based signaling factors that we also validate in mouse data. Ultimately, this work leverages the heterogeneity among single-cell studies to create a comprehensive view of the orchestra of signaling interactions governing PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Camundongos , Microambiente Tumoral , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/genética , Fibroblastos
17.
Headache ; 63(9): 1314-1326, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37466211

RESUMO

BACKGROUND: Melatonin is effective for migraine prevention in adults. We hypothesized that melatonin would also be effective for migraine prevention in children and adolescents. METHODS: This was a randomized, double-blind trial of melatonin (3 mg or 6 mg) versus placebo for migraine prevention in 10-17 year-olds with 4-28/28 headache days at baseline. Participants were recruited from the UCSF Child & Adolescent Headache Program, UCSF child neurology clinic, and social media advertisements. Migraine diagnosis was confirmed by a headache specialist. Participants completed an 8-week single-blind placebo run-in. Those meeting randomization criteria (≥4 headache days and ≥23/28 electronic diary entries during weeks 5-8) were randomized 1:1:1 to placebo:melatonin 3 mg:melatonin 6 mg nightly for 8 weeks. The primary outcome measure was migraine days in weeks 5-8 of randomized treatment between melatonin (combined 6 mg + 3 mg) versus placebo. We aimed to enroll n = 210. RESULTS: The study closed early due to slow enrollment (n = 72). Two participants were in the single-blind phase when the study closed, therefore the meaningful n = 70. Sixteen percent (11/70) were lost to follow-up during the single-blind phase. An additional 21% (15/70) did not meet randomization criteria (<4 headache days: n = 5, <23/28 diary days: n = 7, both: n = 3). Sixty-three percent (44/70) were eligible to randomize, of whom 42 randomized (n = 14 per arm). Taking another preventive at enrollment (OR 8.3, 95% CI 1.01 to 68.9) was the only variable associated with meeting randomization criteria. Of those randomized, 91% (38/42) provided diary data in the final 4-weeks. However, given the amount of missing data, only those with ≥21/28 diary days were analyzed-7/14 (50%) in the placebo group, and 20/28 (71%) in the melatonin groups combined. Median (IQR) migraine/migrainous days in weeks 5-8 of double-blind treatment was 2 (1-7) in the placebo group versus 2 (1-12) in the melatonin groups combined; the difference in medians (95% CI for the difference) was 0 days (-9 to 3). There were no differences in adverse events between groups. CONCLUSIONS: When compared to recall at enrollment, headache days decreased across the single-blind placebo phase and the double-blind phase. There was no suggestion of superiority of melatonin; however, given the substantial portion of missing data, numerically higher in the placebo arm, and underpowering, this should not be interpreted as proof of inefficacy. Melatonin was generally well tolerated with no serious adverse events. Future migraine preventive trials in this age group may find this trial helpful for anticipating enrollment needs if using a single-blind placebo run-in. Enriching for those already on a migraine preventive may improve randomization rates in future trials, though would change the generalizability of results.


Assuntos
Melatonina , Transtornos de Enxaqueca , Adulto , Humanos , Adolescente , Criança , Melatonina/farmacologia , Melatonina/uso terapêutico , Resultado do Tratamento , Método Simples-Cego , Transtornos de Enxaqueca/prevenção & controle , Transtornos de Enxaqueca/tratamento farmacológico , Cefaleia , Método Duplo-Cego
18.
Headache ; 63(7): 942-952, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37313573

RESUMO

BACKGROUND: Youth with continuous (always present) headache are vastly understudied; much remains to be understood regarding treatment response in this population. OBJECTIVE: To describe and explore biopsychosocial factors related to initial clinical outcomes among treatment-seeking youth with continuous headache. METHODS: This retrospective cohort study extracted data of 782 pediatric patients (i.e., aged <18 years) with continuous headache from a large clinical repository. Youth in this study had experienced continuous headache for ≥1 month before presenting to a multidisciplinary headache specialty clinic appointment. Extracted data from this appointment included patients' headache history, clinical diagnoses, and headache-related disability, as well as information about biopsychosocial factors implicated in headache management and/or maintenance (e.g., healthy lifestyle habits, history of feeling anxious or depressed). Additional data regarding patient headache characteristics, disability, and lifestyle habits were extracted from a subset of 529 youth who returned to clinic 4-16 weeks after their initial follow-up visit. After characterizing initial treatment response, exploratory analyses compared youth with the best and worst treatment outcomes on several potentially influential factors. RESULTS: Approximately half of youth (280/526; 53.2%) continued to have continuous headache at follow-up, ~20% of youth (51/526) reported a significant (≥50%) reduction in headache frequency. Improvements in average headache severity (e.g., percentage with severe headaches at initial visit: 45.3% [354/771]; percentage with severe headaches at follow-up visit: 29.8% [156/524]) and headache-related disability were also observed (e.g., percentage severe disability at initial visit: 62.9% [490/779]; percentage severe disability at initial follow-up visit: 34.2% [181/529]). Individuals with the worst headache frequency and disability had a longer history of continuous headache (mean difference estimate = 5.76, p = 0.013) and worse initial disability than the best responders (χ2 [3, 264] = 23.49, p < 0.001). They were also more likely to have new daily persistent headache (χ2 [2, 264] = 12.61, p = 0.002), and were more likely to endorse feeling depressed (χ2 [1, 260] = 11.46, p < 0.001). CONCLUSION: A notable percentage of youth with continuous headache show initial improvements in headache status. Prospective, longitudinal research is needed to rigorously examine factors associated with continuous headache treatment response.


Assuntos
Transtornos de Enxaqueca , Humanos , Adolescente , Criança , Estudos Retrospectivos , Transtornos de Enxaqueca/epidemiologia , Estudos Prospectivos , Cefaleia/epidemiologia , Cefaleia/terapia , Cefaleia/diagnóstico , Resultado do Tratamento
19.
Headache ; 63(6): 805-812, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36757131

RESUMO

OBJECTIVE: To examine group differences in self-reported migraine days among youth who completed the Childhood and Adolescent Migraine Prevention (CHAMP) trial prior to its closure and explore the relationship between self-reported and "nosology-derived" (i.e., International Classification of Headache Disorders, 3rd edition [ICHD-3]) migraine days. BACKGROUND: The CHAMP trial compared amitriptyline and topiramate to placebo for migraine prevention in youth and proposed to analyze change in migraine days as a secondary outcome. There is considerable variability in the field regarding what constitutes a "migraine day," how this is determined and reported in trials, and how consistent these measures are with diagnostic nosology. METHODS: CHAMP trial completers (N = 175) were randomized to receive amitriptyline (n = 77), topiramate (n = 63), or placebo (n = 35). Participants maintained daily headache diaries where they reported each day with headache and if they considered that headache to be a migraine. For each headache day, participants completed a symptom record and reported about symptoms such as pain location(s) and presence of nausea/vomiting or photophobia and phonophobia. We examined group differences in self-reported migraine days at trial completion (summed from trial weeks 20-24) compared to baseline. We also used an algorithm to determine whether participants' symptom reports met ICHD-3 criteria for migraine without aura, and examined the association between self-reported and "nosology-derived" migraine days. RESULTS: Results showed no significant differences between groups in self-reported migraine days over the course of the trial. Self-reported and "nosology-derived" migraine days during the baseline and treatment phases were strongly associated (r's = 0.73 and 0.83, respectively; p's < 0.001). CONCLUSION: Regardless of treatment, CHAMP trial completers showed clinically important reductions in self-reported migraine days over the course of the trial (about 3.8 days less). The strong association between self-reported and "nosology-derived" migraine days suggests youth with migraine can recognize a day with migraine and reliably report their headache features and symptoms. Greater rigor and transparency in the calculation and reporting of migraine days in trials is needed.


Assuntos
Transtornos da Cefaleia , Transtornos de Enxaqueca , Humanos , Criança , Adolescente , Topiramato/uso terapêutico , Autorrelato , Amitriptilina , Frutose/uso terapêutico , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/prevenção & controle , Transtornos de Enxaqueca/diagnóstico , Avaliação de Resultados em Cuidados de Saúde , Transtornos da Cefaleia/tratamento farmacológico , Cefaleia/tratamento farmacológico , Resultado do Tratamento , Método Duplo-Cego
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