Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Fam Pract ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39026426

RESUMO

BACKGROUND: While nearly 50% of adult women report at least one episode of urinary incontinence (UI), most never receive treatment. OBJECTIVE: To better integrate primary and specialty UI care, we conducted (i) an environmental scan to assess the availability of key pathway resources in primary care, (ii) interviews with primary care providers to understand barriers to care, and (iii) a pilot UI care pathway intervention. METHODS: Environmental scan: Clinic managers from all primary care clinics within a Midwestern healthcare system were invited to participate in an interview covering the availability of clinic resources. Provider interviews: Primary care providers were invited to participate in an interview covering current practices and perceived barriers to UI care. Pilot UI care pathway: Patients who screened positive for UI were provided resources for first-line behavioral management. Pilot patients completed questionnaires at baseline, 8 weeks, and 6 months. RESULTS: While many clinics had point-of-care urinalysis (17/21, 81%), most did not have a working bladder ultrasound (14/21, 67%) or on-site pelvic floor physical therapy (18/21, 86%). Providers (n = 5) described barriers to completing almost every step of diagnosis and treatment for UI. The most persistent barrier was lack of time. Patients (n = 15) reported several self-treatment strategies including avoiding bladder irritants (7/15, 47%) and performing Kegel exercises (4/15, 27%). Five patients (33%) requested follow-up care. At 6 months, patients reported small improvements in UI symptoms. CONCLUSION: Promising results from a novel UI care pathway pilot indicate that streamlining UI care may assist primary care providers in the first-line treatment of UI.


Although the majority of women will experience urine leakage at some point during their lives, most will never receive treatment. To better understand this discrepancy, we embarked on a multimodal investigation into the barriers to care and trialed a new treatment pathway in the primary care setting within a large academic medical system in the Midwest. Speaking with the clinic managers from 21 primary care clinics, we determined that many clinics lacked the tools to perform the steps outlined in the professional society guidelines for urinary incontinence diagnosis. Additionally, there was limited access to pelvic floor physical therapy, a proven treatment strategy. Interviews with five primary care providers revealed barriers, most notably lack of time during clinic visits, to almost every step of diagnosis and treatment. Finally, we trialed a care pathway for primary care providers to make it easier to provide patients with self-management education or to refer them to specialist care. Fifteen patients participated in a pilot study, about half reported trying self-management, and about 1/3 requested follow-up care. Streamlining urinary incontinence care at the primary care level may alleviate some of the barriers to patients receiving care.

2.
J Biol Chem ; 298(3): 101590, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35033535

RESUMO

Ribosomal RNAs (rRNAs) have long been known to carry chemical modifications, including 2'O-methylation, pseudouridylation, N6-methyladenosine (m6A), and N6,6-dimethyladenosine. While the functions of many of these modifications are unclear, some are highly conserved and occur in regions of the ribosome critical for mRNA decoding. Both 28S rRNA and 18S rRNA carry single m6A sites, and while the methyltransferase ZCCHC4 has been identified as the enzyme responsible for the 28S rRNA m6A modification, the methyltransferase responsible for the 18S rRNA m6A modification has remained unclear. Here, we show that the METTL5-TRMT112 methyltransferase complex installs the m6A modification at position 1832 of human 18S rRNA. Our work supports findings that TRMT112 is required for METTL5 stability and reveals that human METTL5 mutations associated with microcephaly and intellectual disability disrupt this interaction. We show that loss of METTL5 in human cancer cell lines and in mice regulates gene expression at the translational level; additionally, Mettl5 knockout mice display reduced body size and evidence of metabolic defects. While recent work has focused heavily on m6A modifications in mRNA and their roles in mRNA processing and translation, we demonstrate here that deorphanizing putative methyltransferase enzymes can reveal previously unappreciated regulatory roles for m6A in noncoding RNAs.


Assuntos
Metiltransferases , RNA Mensageiro , RNA Ribossômico 18S , Adenosina/análogos & derivados , Animais , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Ribossômico 18S/genética , RNA Ribossômico 18S/metabolismo , RNA Ribossômico 28S/metabolismo
3.
Exerc Sport Sci Rev ; 50(3): 137-144, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35522248

RESUMO

Aging induces physiological and molecular changes in the heart that increase the risk for heart disease. Several of these changes are targetable by exercise. We hypothesize that the mechanisms by which exercise improves cardiac function in the aged heart differ from those in the young exercised heart.


Assuntos
Miocárdio , Remodelação Ventricular , Idoso , Envelhecimento/fisiologia , Coração , Humanos , Remodelação Ventricular/fisiologia
4.
Development ; 145(6)2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29490985

RESUMO

The molecular clock plays key roles in daily physiological functions, development and cancer. Period 2 (PER2) is a repressive element, which inhibits transcription activated by positive clock elements, resulting in diurnal cycling of genes. However, there are gaps in our understanding of the role of the clock in normal development outside of its time-keeping function. Here, we show that PER2 has a noncircadian function that is crucial to mammalian mammary gland development. Virgin Per2-deficient mice, Per2-/- , have underdeveloped glands, containing fewer bifurcations and terminal ducts than glands of wild-type mice. Using a transplantation model, we show that these changes are intrinsic to the gland and further identify changes in cell fate commitment. Per2-/- mouse mammary glands have a dual luminal/basal phenotypic character in cells of the ductal epithelium. We identified colocalization of E-cadherin and keratin 14 in luminal cells. Similar results were demonstrated using MCF10A and shPER2 MCF10A human cell lines. Collectively this study reveals a crucial noncircadian function of PER2 in mammalian mammary gland development, validates the Per2-/- model, and describes a potential role for PER2 in breast cancer.


Assuntos
Glândulas Mamárias Animais/crescimento & desenvolvimento , Proteínas Circadianas Period/metabolismo , Animais , Ritmo Circadiano/genética , Células Epiteliais/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Glândulas Mamárias Animais/metabolismo , Camundongos , Organogênese , Reação em Cadeia da Polimerase em Tempo Real
5.
J Circadian Rhythms ; 18: 7, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33384723

RESUMO

Critical biological processes are under control of the circadian clock. Disruption of this clock, e.g. during aging, results in increased risk for development of chronic disease. Exercise is a protective intervention that elicits changes in both age and circadian pathologies, yet its role in regulating circadian gene expression in peripheral tissues is unknown. We hypothesized that voluntary wheel running would restore disrupted circadian rhythm in aged mice. We analyzed wheel running patterns and expression of circadian regulators in male and female C57Bl/6J mice in adult (~4 months) and old (~18 months) ages. As expected, young female mice ran further than male mice, and old mice ran significantly less than young mice. Older mice of both sexes had a delayed start time in activity which likely points to a disrupted diurnal running pattern and circadian disruption. Voluntary wheel running rescued some circadian dysfunction in older females. This effect was not present in older males, and whether this was due to low wheel running distance or circadian output is not clear and warrants a future study. Overall, we show that voluntary wheel running can rescue some circadian dysfunction in older female but not male mice; and these changes are tissue dependent. While voluntary running was not sufficient to fully rescue age-related changes in circadian rhythm, ongoing studies will determine if forced exercise (e.g. treadmill) and/or chrono-timed exercise can improve age-related cardiovascular, skeletal muscle, and circadian dysfunction.

6.
Medicina (Kaunas) ; 56(9)2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32899136

RESUMO

Background and Objective: Skeletal muscle is critical for overall health and predicts quality of life in several chronic diseases, thus quantification of muscle mass and composition is necessary to understand how interventions promote changes in muscle quality. The purpose of this investigation was to quantify changes in muscle mass and composition in two distinct pre-clinical models of changes in muscle quality using a clinical dual X-ray absorptiometry (DEXA), validated for use in mice. Materials and Methods: Adult C57Bl6 male mice were given running wheels (RUN; muscle hypertrophy) or placed in hypobaric hypoxia (HH; muscle atrophy) for four weeks. Animals received weekly DEXA and terminal collection of muscle hind limb complex (HLC) and quadriceps weights and signaling for molecular regulators of muscle mass and composition. Results: HH decreased total HLC muscle mass with no changes in muscle composition. RUN induced loss of fat mass in both the quadriceps and HLC. Molecular mediators of atrophy were upregulated in HH while stimulators of muscle growth were higher in RUN. These changes in muscle mass and composition were quantified by a clinical DEXA, which we described and validated for use in pre-clinical models. Conclusions: RUN improves muscle composition while HH promotes muscle atrophy, though changes in composition in hypoxia remain unclear. Use of the widely available clinical DEXA for use in mice enhances translational research capacity to understand the mechanisms by which atrophy and hypertrophy promote skeletal muscle and overall health.


Assuntos
Composição Corporal , Qualidade de Vida , Absorciometria de Fóton , Animais , Hipóxia , Masculino , Camundongos , Músculo Esquelético/diagnóstico por imagem
7.
Am J Physiol Renal Physiol ; 317(5): F1087-F1093, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31461350

RESUMO

The mammalian circadian clock governs physiological, endocrine, and metabolic responses coordinated in a 24-h rhythmic pattern by the suprachiasmatic nucleus (SCN) of the anterior hypothalamus. The SCN also dictates circadian rhythms in peripheral tissues like the kidney. The kidney has several important physiological functions, including removing waste and filtering the blood and regulating fluid volume, blood osmolarity, blood pressure, and Ca2+ metabolism, all of which are under tight control of the molecular/circadian clock. Normal aging has a profound influence on renal function, central and peripheral circadian rhythms, and the sleep-wake cycle. Disrupted circadian rhythms in the kidney as a result of increased age likely contribute to adverse health outcomes such as nocturia, hypertension, and increased risk for stroke, cardiovascular disease, and end organ failure. Regular physical activity improves circadian misalignment in both young and old mammals, although the precise mechanisms for this protection remain poorly described. Recent advances in the heart and skeletal muscle literature suggest that regular endurance exercise entrains peripheral clocks, and we propose that similar beneficial adaptations occur in the kidney through regulation of renal blood flow and fluid balance.


Assuntos
Relógios Biológicos/fisiologia , Exercício Físico/fisiologia , Rim/fisiologia , Adaptação Fisiológica , Humanos , Músculo Esquelético/fisiologia , Equilíbrio Hidroeletrolítico
8.
Mol Pharmacol ; 91(3): 178-188, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28007926

RESUMO

The circadian clock plays a role in many biologic processes, yet very little is known about its role in metabolism of drugs and carcinogens. The purpose of this study was to define the impact of circadian rhythms on benzo-a-pyrene (BaP) metabolism in the mouse mammary gland and develop a circadian in vitro model for investigating changes in BaP metabolism resulting from cross-talk between the molecular clock and aryl hydrocarbon receptor. Female 129sv mice (12 weeks old) received a single gavage dose of 50 mg/kg BaP at either noon or midnight, and mammary tissues were isolated 4 or 24 hours later. BaP-induced Cyp1a1 and Cyp1b1 mRNA levels were higher 4 hours after dosing at noon than at 4 hours after dosing at midnight, and this corresponded with parallel changes in Per gene expression. In our in vitro model, we dosed MCF10A mammary cells at different times after serum shock to study how time of day shifts drug metabolism in cells. Analysis of CYP1A1 and CYP1B1 gene expression showed the maximum enzyme-induced metabolism response 12 and 20 hours after shock, as determined by ethoxyresorufin-O-deethylase activity, metabolism of BaP, and formation of DNA-BaP adducts. The pattern of PER-, BMAL-, and aryl hydrocarbon receptor-induced P450 gene expression and BaP metabolism was similar to BaP-induced Cyp1A1 and Cyp1B1 and molecular clock gene expression in mouse mammary glands. These studies indicate time-of-day exposure influences BaP metabolism in mouse mammary glands and describe an in vitro model that can be used to investigate the circadian influence on the metabolism of carcinogens.


Assuntos
Benzo(a)pireno/metabolismo , Mama/citologia , Ritmo Circadiano , Adutos de DNA/metabolismo , Glândulas Mamárias Animais/citologia , Animais , Biomarcadores/metabolismo , Mama/metabolismo , Proteínas CLOCK/genética , Proteínas CLOCK/metabolismo , Linhagem Celular , Ritmo Circadiano/genética , Citocromo P-450 CYP1A1/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Camundongos , Modelos Biológicos
9.
Artigo em Inglês | MEDLINE | ID: mdl-38954604

RESUMO

IMPORTANCE: Guideline-recommended medications for overactive bladder and urge urinary incontinence (OAB/UUI) are effective but have high costs and side effects. Little is known about patient concerns regarding these medications when prescribed by their primary care providers (PCPs). OBJECTIVE: The aim of the study was to describe PCP-patient interactions when prescribing medications for OAB/UUI, specifically clinical concerns, cost and authorization issues, and mode of communication for these interactions. STUDY DESIGN: Using electronic health records, we identified a retrospective cohort of women aged 18-89 years who were prescribed a medication for OAB/UUI during a primary care office visit from 2017 to 2018. We examined the electronic health record from initial prescription through 15 subsequent months for documentation of prior authorization requests and patient concerns about cost, side effects, or ineffectiveness. The association of patient demographics, comorbidity, and medication class with these concerns was examined with logistic regression models. RESULTS: Overall, 46.2% of patients (n = 123) had 1 or more OAB/UUI medication concerns, and 52 reported outside an office visit. Only higher comorbidity was associated with reduced concern of any type. Although the overall percent age of patients reporting concerns was similar by medication type, the patterns of concern type varied. Compared with those taking short-acting antimuscarinics, patients taking long-acting antimuscarinics other than oxybutynin were less likely to have side effect concerns (adjusted odds ratio 0.35, 95% CI 0.16-0.78) and more likely to have cost concerns (adjusted odds ratio 5.10, 95% CI 1.53-17.03). CONCLUSIONS: Patient concerns regarding OAB/UUI medications were common in primary care practices and frequently reported outside of office visits. However, the patterns of concerns (cost vs side effects) varied between medication classes.

10.
bioRxiv ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38854016

RESUMO

A better understanding of nicotine neurobiology is needed to reduce or prevent chronic addiction, ameliorate the detrimental effects of nicotine withdrawal, and increase successful cessation of use. Nicotine binds and activates two astrocyte-expressed nicotinic acetylcholine receptors (nAChRs), α4ß2 and α7. We recently found that Protein kinase B-ß (Pkb-ß or Akt2) expression is restricted to astrocytes in mice and humans. To determine if AKT2 plays a role in astrocytic nicotinic responses, we generated astrocyte-specific Akt2 conditional knockout (cKO) and full Akt2 KO mice for in vivo and in vitro experiments. For in vivo studies, we examined mice exposed to chronic nicotine for two weeks in drinking water (200 µg/mL) and following acute nicotine challenge (0.09, 0.2 mg/kg) after 24 hrs. Our in vitro studies used cultured mouse astrocytes to measure nicotine-dependent astrocytic responses. We validated our approaches using lipopolysaccharide (LPS) exposure inducing astrogliosis. Sholl analysis was used to measure glial fibrillary acidic protein responses in astrocytes. Our data show that wild-type (WT) mice exhibit increased astrocyte morphological complexity during acute nicotine exposure, with decreasing complexity during chronic nicotine use, whereas Akt2 cKO mice showed increased astrocyte morphology complexity. In culture, we found that 100µM nicotine was sufficient for morphological changes and blocking α7 or α4ß2 nAChRs prevented observed morphologic changes. Finally, we performed conditioned place preference (CPP) in Akt2 cKO mice and found that astrocytic AKT2 deficiency reduced nicotine preference compared to controls. These findings show the importance of nAChRs and Akt2 signaling in the astrocytic response to nicotine.

11.
JTO Clin Res Rep ; 5(2): 100637, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38361741

RESUMO

Introduction: Acquired MET gene amplification, MET exon 14 skip mutations, or MET fusions can emerge as resistance mechanisms to tyrosine kinase inhibitors (TKIs) in patients with lung cancer. The efficacy and safety of combining MET TKIs (such as crizotinib, capmatinib, or tepotinib) with parent TKIs to target acquired MET resistance are not well characterized. Methods: Multi-institutional retrospective chart review identified 83 patients with metastatic oncogene-driven NSCLC that were separated into the following two pairwise matched cohorts: (1) MET cohort (n = 41)-patients with acquired MET resistance continuing their parent TKI with a MET TKI added or (2) Chemotherapy cohort (n = 42)-patients without any actionable resistance continuing their parent TKI with a platinum-pemetrexed added. Clinicopathologic features, radiographic response (by means of Response Evaluation Criteria in Solid Tumors version 1.1), survival outcomes, adverse events (AEs) (by means of Common Terminology Criteria for Adverse Events version 5.0), and genomic data were collected. Survival outcomes were assessed using Kaplan-Meier methods. Multivariate modeling adjusted for lines of therapy, brain metastases, TP53 mutations, and oligometastatic disease. Results: Within the MET cohort, median age was 56 years (range: 36-83 y). Most patients were never smokers (28 of 41, 68.3%). Baseline brain metastases were common (21 of 41, 51%). The most common oncogenes in the MET cohort were EGFR (30 of 41, 73.2%), ALK (seven of 41, 17.1%), and ROS1 (two of 41, 4.9%). Co-occurring TP53 mutations (32 of 41, 78%) were frequent. Acquired MET alterations included MET gene amplification (37 of 41, 90%), MET exon 14 mutations (two of 41, 5%), and MET gene fusions (two of 41, 5%). After multivariate adjustment, the objective response rate (ORR) was higher in the MET cohort versus the chemotherapy cohort (ORR: 69.2% versus 20%, p < 0.001). Within the MET cohort, MET gene copy number (≥10 versus 6-10) did not affect radiographic response (54.5% versus 68.4%, p = 0.698). There was no difference in ORR on the basis of MET TKI used (F [2, 36] = 0.021, p = 0.978). There was no difference in progression-free survival (5 versus 6 mo; hazard ratio = 0.64; 95% confidence interval: 0.34-1.23, p = 0.18) or overall survival (13 versus 11 mo; hazard ratio = 0.75; 95% confidence interval: 0.42-1.35, p = 0.34) between the MET and chemotherapy cohorts. In the MET cohort, dose reductions for MET TKI-related toxicities were common (17 of 41, 41.4%) but less frequent for parent TKIs (two of 41, 5%). Grade 3 AEs were not significant between crizotinib, capmatinib, and tepotinib (p = 0.3). The discontinuation rate of MET TKIs was 17% with no significant differences between MET TKIs (p = 0.315). Among pre- and post-treatment biopsies (n = 17) in the MET cohort, the most common next-generation sequencing findings were loss of MET gene amplification (15 of 17, 88.2%), MET on-target mutations (seven of 17, 41.2%), new Ras-Raf-MAPK alterations (three of 17, 17.6%), and EGFR gene amplification (two of 17, 11.7%). Conclusions: The efficacy and safety of combining MET TKIs (crizotinib, capmatinib, or tepotinib) with parent TKIs for acquired MET resistance are efficacious. Radiographic response and AEs did not differ significantly on the basis of the underlying MET TKI used. Loss of MET gene amplification, development of MET on-target mutations, Ras-Raf-MAPK alterations, and EGFR gene amplification were molecular patterns found on progression with dual parent and MET TKI combinations.

12.
Nutrients ; 15(13)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37447184

RESUMO

Diet influences critical periods of growth, including gestation and early development. We hypothesized that a maternal/early life diet reflecting unprocessed dietary components would positively affect offspring metabolic and anthropometric parameters. Using 9 C57BL-6 dams, we simulated exposure to a Western diet, a high-fiber unprocessed diet (HFUD), or a control diet. The dams consumed their respective diets (Western [n = 3], HFUD [n = 3], and control [n = 3]) through 3 weeks of pregnancy and 3 weeks of weaning; their offspring consumed the diet of their mother for 4.5 weeks post weaning. Measurements included dual X-ray absorptiometry (DEXA) scans, feed consumption, body weight, blood glucose, and insulin and glycated hemoglobin (HbA1c) in the offspring. Statistical analyses included one-way ANOVA with Tukey's post hoc analysis. The offspring DEXA measures at 5 and 7.5 weeks post parturition revealed higher lean body mass development in the HFUD and control diet offspring compared to the Western diet offspring. An analysis indicated that blood glucose (p = 0.001) and HbA1c concentrations (p = 0.002) were lower among the HFUD offspring compared to the Western and control offspring. The results demonstrate that diet during gestation and early life consistent with traditional diet patterns may influence hyperglycemia and adiposity in offspring.


Assuntos
Dieta Ocidental , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Feminino , Camundongos , Animais , Humanos , Dieta Ocidental/efeitos adversos , Glicemia/metabolismo , Hemoglobinas Glicadas , Camundongos Endogâmicos C57BL , Peso Corporal , Dieta , Avaliação de Resultados em Cuidados de Saúde , Dieta Hiperlipídica , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Fenômenos Fisiológicos da Nutrição Materna
13.
J Biol Rhythms ; 38(3): 290-304, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36802963

RESUMO

Circadian misalignment occurs with age, jet lag, and shift work, leading to maladaptive health outcomes including cardiovascular diseases. Despite the strong link between circadian disruption and heart disease, the cardiac circadian clock is poorly understood, prohibiting identification of therapies to restore the broken clock. Exercise is the most cardioprotective intervention identified to date and has been suggested to reset the circadian clock in other peripheral tissues. Here, we tested the hypothesis that conditional deletion of core circadian gene Bmal1 would disrupt cardiac circadian rhythm and function and that this disruption would be ameliorated by exercise. To test this hypothesis, we generated a transgenic mouse with spatial and temporal deletion of Bmal1 only in adult cardiac myocytes (Bmal1 cardiac knockout [cKO]). Bmal1 cKO mice demonstrated cardiac hypertrophy and fibrosis concomitant with impaired systolic function. This pathological cardiac remodeling was not rescued by wheel running. While the molecular mechanisms responsible for the profound cardiac remodeling are unclear, it does not appear to involve activation of the mammalian target of rapamycin (mTOR) signaling or changes in metabolic gene expression. Interestingly, cardiac deletion of Bmal1 disrupted systemic rhythms as evidenced by changes in the onset and phasing of activity in relationship to the light/dark cycle and by decreased periodogram power as measured by core temperature, suggesting cardiac clocks can regulate systemic circadian output. Together, we suggest a critical role for cardiac Bmal1 in regulating both cardiac and systemic circadian rhythm and function. Ongoing experiments will determine how disruption of the circadian clock causes cardiac remodeling in an effort to identify therapeutics to attenuate the maladaptive outcomes of a broken cardiac circadian clock.


Assuntos
Relógios Circadianos , Cardiopatias , Camundongos , Animais , Ritmo Circadiano/genética , Atividade Motora/fisiologia , Relógios Circadianos/genética , Camundongos Transgênicos , Camundongos Knockout , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Mamíferos/metabolismo
14.
J Appl Physiol (1985) ; 135(3): 572-583, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37439235

RESUMO

Cardiovascular disease is an enormous public health problem, particularly in older populations. Exercise is the most potent cardioprotective intervention identified to date, with exercise in the juvenile period potentially imparting greater protection, given the plasticity of the developing heart. To test the hypothesis that voluntary wheel running early in life would be cardioprotective later in life when risk for disease is high, we provided male and female juvenile (3 wk old) mice access to a running wheel for 2 wk. Mice then returned to a home cage to age to adulthood (4-6 mo) before exposure to isoproterenol (ISO) to induce cardiac stress. Cardiac function and remodeling were compared with sedentary control mice, sedentary mice exposed to ISO, and mice that exercised in adulthood immediately before ISO. Early in life activity protected against ISO-induced stress as evidenced by attenuated cardiac mass, myocyte size, and fibrosis compared with sedentary mice exposed to ISO. ISO-induced changes in cardiac function were ameliorated in male mice that engaged in wheel running, with ejection fraction and fractional shortening reversed to control values. Adrenergic receptor expression was downregulated in juvenile male runners. This suppression persisted in adulthood following ISO, providing a putative mechanism by which exercise in the young male heart provides resilience to cardiac stress later in life. Together, we show that activity early in life induces persistent cardiac changes that attenuate ISO-induced stress in adulthood. Identification of the mechanisms by which early in life exercise is protective will yield valuable insights into how exercise is medicine across the life course.NEW & NOTEWORTHY Voluntary wheel running activity early in life induces persistent changes in the heart that attenuate isoproterenol-induced hypertrophy and fibrosis in adulthood. Though the mechanisms of this protection remain incompletely understood, activity-induced downregulation of adrenergic receptor expression early in life may contribute to later protection against adrenergic stress. Together these data suggest that efforts to maintain an active lifestyle early in life may have long-lasting cardioprotective benefits.


Assuntos
Cardiopatias , Atividade Motora , Masculino , Feminino , Camundongos , Animais , Isoproterenol/farmacologia , Atividade Motora/fisiologia , Cardiopatias/metabolismo , Receptores Adrenérgicos/metabolismo , Fibrose , Exercício Físico , Miócitos Cardíacos/metabolismo
15.
Aerosp Med Hum Perform ; 94(12): 887-893, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38176033

RESUMO

INTRODUCTION: High-altitude [>2400 m (7874 ft)] acclimatization has been well studied with physiological adaptations like reductions in body weight and exercise capacity. However, despite the significance of moderate altitude [MA, 1524-2438 m (5000-8000 ft)], acclimatization at this elevation is not well described. We aimed to investigate differences in mice reared at MA compared to sea level (SL). We hypothesized that MA mice would be smaller and leaner and voluntarily run less than SL mice.METHODS: C57BL/6 mice reared for at least three generations in Laramie, WY [2194 m (7198 ft), MA], were compared to C57BL/6J mice from Bar Harbor, ME [20 m (66 ft), SL]. We quantified body composition and exercise outputs as well as cardiopulmonary morphometrics. Subsets of MA and SL mice were analyzed to determine differences in neuronal activation after exercise.RESULTS: When body weight was normalized to tibia length, SL animals weighed 1.30 g ⋅ mm-1 while MA mice weighed 1.13 g · mm-1. Total fat % and trunk fat % were higher in MA mice with values of 41% and 39%, respectively, compared to SL mice with values of 28% and 26%, respectively. However, no differences were noted in leg fat %. MA animals had higher heart mass (119 mg) and lower lung mass (160 mg) compared to SL mice heart mass (100 mg) and lung mass (177 mg). MA mice engaged in about 40% less voluntary wheel-running activity than SL animals.DISCUSSION: Physiological differences are apparent between MA and SL mice, prompting a need to further understand larger scale implications of residence at moderate altitude.O'Connor AE, Hatzenbiler DM, Flom LT, Bobadilla A-C, Bruns DR, Schmitt EE. Physiological and morphometric differences in resident moderate-altitude vs. sea-level mice. Aerosp Med Hum Perform. 2023; 94(12):887-893.


Assuntos
Doença da Altitude , Altitude , Animais , Camundongos , Camundongos Endogâmicos C57BL , Aclimatação/fisiologia , Peso Corporal
16.
Artigo em Inglês | MEDLINE | ID: mdl-37881958

RESUMO

IMPORTANCE: Although behavioral modifications, medications, and other interventions can improve urinary incontinence (UI), many women never receive them. OBJECTIVES: To better characterize UI treatment patterns in primary care, we examined prescriptions and referrals to pelvic floor physical therapy (PFPT) and specialist physicians within a large Midwestern academic health system. STUDY DESIGN: Electronic health records were queried to identify a cohort of adult female patients receiving a new UI diagnosis during outpatient primary care visits from 2016 to 2020. Urinary incontinence referrals and referral completion were examined for the overall cohort, and medication prescriptions were examined for women with urgency or mixed UI. Logistic regression was used to assess the association of prescriptions and/or referrals with patient demographics, comorbidities, and UI diagnosis dates. RESULTS: In the year after primary care UI diagnosis, 37.2% of patients in the overall cohort (n = 4,382) received guideline-concordant care. This included 20.6% of women who were referred for further management: 17.7% to urology/urogynecology and 3.2% to PFPT. Most women who were referred attended an initial appointment. Among those with urgency (n = 2,398) or mixed UI (n = 552), 17.1% were prescribed medication. Women with stress (odds ratio [OR], 3.10; 95% CI, 2.53-3.79) and mixed UI (OR, 6.17; 95% CI, 4.03-9.66) were more likely to be referred for further management, and women diagnosed during the COVID-19 pandemic were less likely to be referred for further care (OR, 0.39; 95% CI, 0.29, 0.48). CONCLUSION: Only slightly above 1 in 3 women with a new diagnosis of UI in primary care received guideline-based medications or referrals within 1 year, suggesting missed opportunities for timely care.

17.
Int J Sports Physiol Perform ; 17(8): 1170-1178, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35537708

RESUMO

PURPOSE: To investigate the relationship between pacing strategy and performance during uphill and downhill running-specifically, what distribution of energy corresponds to faster race finish times between and among participants. METHODS: Eighteen years of race data from a 10.2-mile running race with an uphill first half and a downhill second half were analyzed to identify relationships between pacing and performance. A pacing coefficient (PC), equal to a participant's ascent time divided by finishing time (FT), was used to define each participant's pacing strategy. The American College of Sports Medicine metabolic running equation was used to estimate energy expenditure during the ascent, descent, and total race. Statistical analyses compared participants' PC to their FT and finishing place within their age and gender category. Additionally, FT and finishing place were compared between groups of participants who exhibited similar pacing strategies. RESULTS: PCs were positively associated with faster FTs (r2 = .120, P < .001) and better finishing positions (r2 = .104, P < .001). PCs above .600 were associated with the fastest average FTs and best average finishing position within age and gender categories (all P ≤ .047). CONCLUSIONS: Participants performed the best when energy expenditure increased no more than 10.4% during the uphill portion compared to their overall average. It is not possible to state that overly aggressive uphill efforts resulted in premature fatigue and thus slower decent times and worse race performance. However, participants should still avoid overly aggressive uphill pacing, as performance was associated with larger PCs.


Assuntos
Corrida , Metabolismo Energético , Fadiga , Humanos
18.
High Alt Med Biol ; 23(3): 215-222, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35653735

RESUMO

Fullerton, Zackery S., Benjamin D. McNair, Nicholas A. Marcello, Emily E. Schmitt, and Danielle R. Bruns. Exposure to high altitude promotes loss of muscle mass that is not rescued by metformin. High Alt Med Biol. 23:215-222, 2022. Background: Exposure to high altitude (HA) causes muscle atrophy. Few therapeutic interventions attenuate muscle atrophy; however, the diabetic drug, metformin (Met), has been suggested as a potential therapeutic to preserve muscle mass with aging and obesity-related atrophy. The purpose of the present study was to test the hypothesis that HA would induce muscle atrophy that could be attenuated by Met. Methods: C57Bl6 male and female mice were exposed to simulated HA (∼5,200 m) for 4 weeks, while control (Con) mice remained at resident altitude (∼2,180 m). Met was administered in drinking water at 200 mg/(kg·day). We assessed muscle mass, myocyte cell size, muscle and body composition, and expression of molecular mediators of atrophy. Results: Mice exposed to HA were leaner and had a smaller hind limb complex (HLC) mass than Con mice. Loss of HLC mass and myocyte size were not attenuated by Met. Molecular markers for muscle atrophy were activated at HA in a sex-dependent manner. While the atrophic regulator, atrogin, was unchanged at HA or with Met, myostatin expression was upregulated at HA. In female mice, Met further stimulated myostatin expression. Conclusions: Although HA exposure resulted in loss of muscle mass, particularly in male mice, Met did not attenuate muscle atrophy. Identification of other interventions to preserve muscle mass during ascent to HA is warranted.


Assuntos
Metformina , Miostatina , Altitude , Animais , Feminino , Masculino , Metformina/metabolismo , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Músculos/metabolismo , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Miostatina/metabolismo
19.
Physiol Rep ; 9(13): e14940, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34245129

RESUMO

Risk for heart disease increases with advanced age and differs between sexes, with females generally protected from heart disease until menopause. Despite these epidemiological observations, the molecular mechanisms that underlie sex-specific differences in cardiac function have not been fully described. We used high throughput transcriptomics in juvenile (5 weeks), adult (4-6 months), and aged (18 months) male and female mice to understand how cardiac gene expression changes across the life course and by sex. While male gene expression profiles differed between juvenile-adult and juvenile-aged (254 and 518 genes, respectively), we found no significant differences in adult-aged gene expression. Females had distinct gene expression changes across the life course with 1835 genes in juvenile-adult and 1328 in adult-aged. Analysis of differentially expressed genes (DEGs) suggests that juvenile to adulthood genes were clustered in cell cycle and development-related pathways in contrast to adulthood-aged which were characterized by immune-and inflammation-related pathways. Analysis of sex differences within each age suggests that juvenile and aged cardiac transcriptomes are different between males and females, with significantly fewer DEGs identified in adult males and females. Interestingly, the male-female differences in early age were distinct from those in advanced age. These findings are in contrast to expected sex differences historically attributed to estrogen and could not be explained by estrogen-direct mechanisms alone as evidenced by juvenile sexual immaturity and reproductive incompetence in the aged mice. Together, distinct trajectories in cardiac transcriptomic profiles highlight fundamental sex differences across the life course and demonstrate the need for the consideration of age and sex as biological variables in heart disease.


Assuntos
Perfilação da Expressão Gênica , Expressão Gênica , Miocárdio/metabolismo , Fatores Etários , Envelhecimento/fisiologia , Animais , Feminino , Expressão Gênica/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteômica , Análise de Sequência de RNA , Fatores Sexuais
20.
Geroscience ; 43(4): 1799-1813, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33651247

RESUMO

The aging heart is well-characterized by a diminished responsiveness to adrenergic activation. However, the precise mechanisms by which age and sex impact adrenergic-mediated cardiac function remain poorly described. In the current investigation, we compared the cardiac response to adrenergic stress to gain mechanistic understanding of how the response to an adrenergic challenge differs by sex and age. Juvenile (4 weeks), adult (4-6 months), and aged (18-20 months) male and female mice were treated with the ß-agonist isoproterenol (ISO) for 1 week. ISO-induced morphometric changes were age- and sex-dependent as juvenile and adult mice of both sexes had higher left ventricle weights while aged mice did not increase cardiac mass. Adults increased myocyte cell size and deposited fibrotic matrix in response to ISO, while juvenile and aged animals did not show evidence of hypertrophy or fibrosis. Juvenile females and adults underwent expected changes in systolic function with higher heart rate, ejection fraction, and fractional shortening. However, cardiac function in aged animals was not altered in response to ISO. Transcriptomic analysis identified significant differences in gene expression by age and sex, with few overlapping genes and pathways between groups. Fibrotic and adrenergic signaling pathways were upregulated in adult hearts. Juvenile hearts upregulated genes in the adrenergic pathway with few changes in fibrosis, while aged mice robustly upregulated fibrotic gene expression without changes in adrenergic genes. We suggest that the response to adrenergic stress significantly differs across the lifespan and by sex. Mechanistic definition of these age-related pathways by sex is critical for future research aimed at treating age-related cardiac adrenergic desensitization.


Assuntos
Agonistas Adrenérgicos beta , Miócitos Cardíacos , Adrenérgicos , Agonistas Adrenérgicos beta/farmacologia , Animais , Feminino , Isoproterenol/farmacologia , Longevidade , Masculino , Camundongos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA