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1.
Proc Natl Acad Sci U S A ; 119(21): e2116311119, 2022 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-35580181

RESUMEN

Does local partisan context influence the adoption of prosocial behavior? Using a nationwide survey of 60,000 adults and geographic data on over 180 million registered voters, we investigate whether neighborhood partisan composition affects a publicly observable and politicized behavior: wearing a mask. We find that Republicans are less likely to wear masks in public as the share of Republicans in their zip codes increases. Democratic mask wearing, however, is unaffected by local partisan context. Consequently, the partisan gap in mask wearing is largest in Republican neighborhoods, and less apparent in Democratic areas. These effects are distinct from other contextual effects such as variations in neighborhood race, income, or education. In contrast, partisan context has significantly reduced influence on unobservable public health recommendations like COVID-19 vaccination and no influence on nonpoliticized behaviors like flu vaccination, suggesting that differences in mask wearing reflect the publicly observable and politicized nature of the behavior instead of underlying differences in dispositions toward medical care.


Asunto(s)
Altruismo , COVID-19 , Máscaras , Política , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Conducta de Masa , Estados Unidos , Vacunación/psicología
2.
Chaos ; 34(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38260937

RESUMEN

With the recent increase in deforestation, forest fires, and regional temperatures, the concerns around the rapid and complete collapse of the Amazon rainforest ecosystem have heightened. The thresholds of deforestation and the temperature increase required for such a catastrophic event are still uncertain. However, our analysis presented here shows that signatures of changing Amazon are already apparent in historical climate data sets. Here, we extend the methods of climate network analysis and apply them to study the temporal evolution of the connectivity between the Amazon rainforest and the global climate system. We observe that the Amazon rainforest is losing short-range connectivity and gaining more long-range connections, indicating shifts in regional-scale processes. Using embeddings inspired by manifold learning, we show that the Amazon connectivity patterns have undergone a fundamental shift in the 21st century. By investigating edge-based network metrics on similar regions to the Amazon, we see the changing properties of the Amazon are noticeable in comparison. Furthermore, we simulate diffusion and random walks on these networks and observe a faster spread of perturbations from the Amazon in recent decades. Our methodology innovations can act as a template for examining the spatiotemporal patterns of regional climate change and its impact on global climate using the toolbox of climate network analysis.

3.
J Physiol ; 601(23): 5277-5293, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37878529

RESUMEN

Our laboratory previously showed lipid hydroperoxides and oxylipin levels are elevated in response to loss of skeletal muscle innervation and are associated with muscle pathologies. To elucidate the pathological impact of lipid hydroperoxides, we overexpressed glutathione peroxidase 4 (GPx4), an enzyme that targets reduction of lipid hydroperoxides in membranes, in adult CuZn superoxide dismutase knockout (Sod1KO) mice that show accelerated muscle atrophy associated with loss of innervation. The gastrocnemius muscle from Sod1KO mice shows reduced mitochondrial respiration and elevated oxidative stress (F2 -isoprostanes and hydroperoxides) compared to wild-type (WT) mice. Overexpression of GPx4 improved mitochondrial respiration and reduced hydroperoxide generation in Sod1KO mice, but did not attenuate the muscle loss that occurs in Sod1KO mice. In contrast, contractile force generation is reduced in EDL muscle in Sod1KO mice relative to WT mice, and overexpression of GPx4 restored force generation to WT levels in Sod1KO mice. GPx4 overexpression also prevented loss of muscle contractility at the single fibre level in fast-twitch fibres from Sod1KO mice. Muscle fibres from Sod1KO mice were less sensitive to both depolarization and calcium at the single fibre level and exhibited a reduced activation by S-glutathionylation. GPx4 overexpression in Sod1KO mice rescued the deficits in both membrane excitability and calcium sensitivity of fast-twitch muscle fibres. Overexpression of GPx4 also restored the sarco/endoplasmic reticulum Ca2+ -ATPase activity in Sod1KO gastrocnemius muscles. These data suggest that GPx4 plays an important role in preserving excitation-contraction coupling function and Ca2+ homeostasis, and in maintaining muscle and mitochondrial function in oxidative stress-induced sarcopenia. KEY POINTS: Knockout of CuZn superoxide dismutase (Sod1KO) induces elevated oxidative stress with accelerated muscle atrophy and weakness. Glutathione peroxidase 4 (GPx4) plays a fundamental role in the reduction of lipid hydroperoxides in membranes, and overexpression of GPx4 improves mitochondrial respiration and reduces hydroperoxide generation in Sod1KO mice. Muscle contractile function deficits in Sod1KO mice are alleviated by the overexpression of GPx4. GPx4 overexpression in Sod1KO mice rescues the impaired muscle membrane excitability of fast-twitch muscle fibres and improves their calcium sensitivity. Sarco/endoplasmic reticulum Ca2+ -ATPase activity in Sod1KO muscles is decreased, and it is restored by the overexpression of GPx4. Our results confirm that GPx4 plays an important role in preserving excitation-contraction coupling function and Ca2+ homeostasis, and maintaining muscle and mitochondrial function in oxidative stress-induced sarcopenia.


Asunto(s)
Sarcopenia , Animales , Ratones , Adenosina Trifosfatasas/genética , Calcio , Glutatión , Glutatión Peroxidasa/genética , Peróxido de Hidrógeno , Lípidos , Ratones Noqueados , Músculo Esquelético/fisiología , Fenotipo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/genética , Superóxido Dismutasa , Superóxido Dismutasa-1/genética
4.
Annu Rev Pharmacol Toxicol ; 60: 311-331, 2020 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-31283429

RESUMEN

Pharmacogenetics is a key component of precision medicine. Genetic variation in drug metabolism enzymes can lead to variable exposure to drugs and metabolites, potentially leading to inefficacy and drug toxicity. Although the evidence for pharmacogenetic associations in children is not as extensive as for adults, there are several drugs across diverse therapeutic areas with robust pediatric data indicating important, and relatively common, drug-gene interactions. Guidelines to assist gene-based dose optimization are available for codeine, thiopurine drugs, selective serotonin reuptake inhibitors, atomoxetine, tacrolimus, and voriconazole. For each of these drugs, there is an opportunity to clinically implement precision medicine approaches with children for whom genetic test results are known or are obtained at the time of prescribing. For many more drugs that are commonly used in pediatric patients, additional investigation is needed to determine the genetic factors influencing appropriate dose.


Asunto(s)
Preparaciones Farmacéuticas/administración & dosificación , Farmacogenética/métodos , Medicina de Precisión/métodos , Niño , Relación Dosis-Respuesta a Droga , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/prevención & control , Humanos , Preparaciones Farmacéuticas/metabolismo
5.
Cell Biochem Funct ; 41(4): 478-489, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37150891

RESUMEN

Cachexia is characterized by losses in lean body mass and its progression results in worsened quality of life and exacerbated outcomes in cancer patients. However, the role and impact of fibrosis during the early stages and development of cachexia in under-investigated. The purpose of this study was to determine if fibrosis occurs during cachexia development, and to evaluate this in both sexes. Female and male C57BL6/J mice were injected with phosphate-buffered saline or Lewis Lung Carcinoma (LLC) at 8-week of age, and tumors were allowed to develop for 1, 2, 3, or 4 weeks. 3wk and 4wk female tumor-bearing mice displayed a dichotomy in tumor growth and were reassigned to high tumor (HT) and low tumor (LT) groups. In vitro analyses were also performed on cocultured C2C12 and 3T3 cells exposed to LLC conditioned media. Immunohistochemistry and quantitative polymerase chain reaction (qPCR) analysis were used to investigate fibrosis and fibrosis-related signaling in skeletal muscle. Collagen deposition in skeletal muscle was increased in the 1wk, LT, and HT groups in female mice. However, collagen deposition was only increased in the 4wk group in male mice. In general, female mice displayed earlier alterations in extracellular matrix (ECM)-related genes beginning at 1wk post-LLC injection. Whereas this was not seen in males. While overall tumor burden is tightly correlated to cachexia development in both sexes, fibrotic development is not. Male mice did not exhibit early-stage alterations in ECM-related genes contrary to what was noted in female mice.


Asunto(s)
Caquexia , Carcinoma Pulmonar de Lewis , Masculino , Femenino , Animales , Ratones , Caquexia/etiología , Caquexia/patología , Calidad de Vida , Músculo Esquelético/patología , Carcinoma Pulmonar de Lewis/complicaciones , Carcinoma Pulmonar de Lewis/patología , Ratones Endogámicos C57BL
6.
Proc Natl Acad Sci U S A ; 116(24): 11590-11595, 2019 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-31138695

RESUMEN

Exposure to fine particulate matter (PM) during pregnancy is associated with high risks of birth defects/fatality and adverse long-term postnatal health. However, limited mechanistic data are available to assess the detailed impacts of prenatal PM exposure. Here we evaluate fine PM exposure during pregnancy on prenatal/postnatal organogenesis in offspring and in predisposing metabolic syndrome for adult life. Between days 0 and 18 of gestation, two groups of adult female rats (n = 10 for each) were placed in a dual-exposure chamber device, one with clean ambient air (∼3 µg·m-3) and the other with ambient air in the presence of 100 to 200 µg·m-3 of ultrafine aerosols of ammonium sulfate. At birth (postnatal day 0, PND0), four males and four females were selected randomly from each litter to be nursed by dams, whereas tissues were collected from the remaining pups. At PND21, tissues were collected from two males and two females, whereas the remaining pups were fed either a high- or low-fat diet until PND105, when tissues were obtained for biochemical and physiological analyses. Maternal exposure to fine PM increased stillbirths; reduced gestation length and birth weight; increased concentrations of glucose and free fatty acids in plasma; enhanced lipid accumulation in the liver; and decreased endothelium-dependent relaxation of aorta. This lead to altered organogenesis and predisposed progeny to long-term metabolic defects in an age-, organ-, and sex-specific manner. Our results highlight the necessity to develop therapeutic strategies to remedy adverse health effects of maternal PM exposure on conceptus/postnatal growth and development.


Asunto(s)
Exposición Materna/efectos adversos , Síndrome Metabólico/inducido químicamente , Organogénesis/efectos de los fármacos , Material Particulado/efectos adversos , Efectos Tardíos de la Exposición Prenatal/patología , Contaminación del Aire/efectos adversos , Animales , Peso al Nacer/efectos de los fármacos , Susceptibilidad a Enfermedades/sangre , Susceptibilidad a Enfermedades/metabolismo , Susceptibilidad a Enfermedades/patología , Exposición a Riesgos Ambientales/efectos adversos , Ácidos Grasos/sangre , Femenino , Glucosa/metabolismo , Masculino , Síndrome Metabólico/sangre , Síndrome Metabólico/metabolismo , Síndrome Metabólico/patología , Organogénesis/fisiología , Embarazo , Efectos Tardíos de la Exposición Prenatal/sangre , Efectos Tardíos de la Exposición Prenatal/metabolismo , Ratas , Ratas Sprague-Dawley
7.
Int J Mol Sci ; 21(21)2020 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-33105841

RESUMEN

It is established that cancer cachexia causes limb muscle atrophy and is strongly associated with morbidity and mortality; less is known about how the development of cachexia impacts the diaphragm. The purpose of this study was to investigate cellular signaling mechanisms related to mitochondrial function, reactive oxygen species (ROS) production, and protein synthesis during the development of cancer cachexia. C57BL/J6 mice developed Lewis Lung Carcinoma for either 0 weeks (Control), 1 week, 2 weeks, 3 weeks, or 4 weeks. At designated time points, diaphragms were harvested and analyzed. Mitochondrial respiratory control ratio was ~50% lower in experimental groups, which was significant by 2 weeks of cancer development, with no difference in mitochondrial content markers COXIV or VDAC. Compared to the controls, ROS was 4-fold elevated in 2-week animals but then was not different at later time points. Only one antioxidant protein, GPX3, was altered by cancer development (~70% lower in experimental groups). Protein synthesis, measured by a fractional synthesis rate, appeared to become progressively lower with the cancer duration, but the mean difference was not significant. The development and progression of cancer cachexia induces marked alterations to mitochondrial function and ROS production in the diaphragm and may contribute to increased cachexia-associated morbidity and mortality.


Asunto(s)
Caquexia/metabolismo , Carcinoma Pulmonar de Lewis/metabolismo , Diafragma/fisiopatología , Mitocondrias Musculares/metabolismo , Animales , Antioxidantes/metabolismo , Caquexia/etiología , Carcinoma Pulmonar de Lewis/fisiopatología , Diafragma/metabolismo , Proteína Forkhead Box O3/metabolismo , Glutatión Peroxidasa/metabolismo , Masculino , Ratones Endogámicos C57BL , Proteínas Musculares/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal
8.
Physiol Genomics ; 50(12): 1071-1082, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30289747

RESUMEN

Cancer-cachexia (CC) is a wasting condition directly responsible for 20-40% of cancer-related deaths. The mechanisms controlling development of CC-induced muscle wasting are not fully elucidated. Most investigations focus on the postcachectic state and do not examine progression of the condition. We recently demonstrated mitochondrial degenerations precede muscle wasting in time course progression of CC. However, the extent of muscle perturbations before wasting in CC is unknown. Therefore, we performed global gene expression analysis in CC-induced muscle wasting to enhance understanding of intramuscular perturbations across the development of CC. Lewis lung carcinoma (LLC) was injected into the hind-flank of C57BL6/J mice at 8 wk of age with tumor allowed to develop for 1, 2, 3, or 4 wk and compared with PBS-injected control. Muscle wasting was evident at 4 wk LLC. RNA sequencing of gastrocnemius muscle samples showed widespread alterations in LLC compared with PBS animals with largest differences seen in 4 wk LLC, suggesting extensive transcriptomic alterations concurrent to muscle wasting. Commonly altered pathways included: mitochondrial dysfunction and protein ubiquitination, along with other less studied processes in this condition regulating transcription/translation and cytoskeletal structure. Current findings present novel evidence of transcriptomic shifts and altered cellular pathways in CC-induced muscle wasting.


Asunto(s)
Caquexia/genética , Fibras Musculares Esqueléticas/patología , Atrofia Muscular/genética , Transcriptoma/genética , Animales , Caquexia/patología , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/patología , Progresión de la Enfermedad , Perfilación de la Expresión Génica/métodos , Ratones , Ratones Endogámicos C57BL , Mitocondrias/genética , Mitocondrias/patología , Atrofia Muscular/patología
9.
Am J Physiol Regul Integr Comp Physiol ; 315(4): R595-R608, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29949410

RESUMEN

Long-acting glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) agonists (GLP-1RA), such as exendin-4 (Ex4), promote weight loss. On the basis of a newly discovered interaction between GLP-1 and oleoylethanolamide (OEA), we tested whether OEA enhances GLP-1RA-mediated anorectic signaling and weight loss. We analyzed the effect of GLP-1+OEA and Ex4+OEA on canonical GLP-1R signaling and other proteins/pathways that contribute to the hypophagic action of GLP-1RA (AMPK, Akt, mTOR, and glycolysis). We demonstrate that OEA enhances canonical GLP-1R signaling when combined with GLP-1 but not with Ex4. GLP-1 and Ex4 promote phosphorylation of mTOR pathway components, but OEA does not enhance this effect. OEA synergistically enhanced GLP-1- and Ex4-stimulated glycolysis but did not augment the hypophagic action of GLP-1 or Ex4 in lean or diet-induced obese (DIO) mice. However, the combination of Ex4+OEA promoted greater weight loss in DIO mice than Ex4 or OEA alone during a 7-day treatment. This was due in part to transient hypophagia and increased energy expenditure, phenotypes also observed in Ex4-treated DIO mice. Thus, OEA augments specific GLP-1RA-stimulated signaling but appears to work in parallel with Ex4 to promote weight loss in DIO mice. Elucidating cooperative mechanisms underlying Ex4+OEA-mediated weight loss could, therefore, be leveraged toward more effective obesity therapies.


Asunto(s)
Fármacos Antiobesidad/farmacología , Endocannabinoides/farmacología , Exenatida/farmacología , Receptor del Péptido 1 Similar al Glucagón/agonistas , Incretinas/farmacología , Obesidad/tratamiento farmacológico , Ácidos Oléicos/farmacología , Pérdida de Peso/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Células CHO , Cricetulus , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Quimioterapia Combinada , Conducta Alimentaria/efectos de los fármacos , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Glucólisis/efectos de los fármacos , Masculino , Ratones Endogámicos C57BL , Obesidad/metabolismo , Obesidad/fisiopatología , Obesidad/psicología , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo
10.
Physiol Genomics ; 49(5): 253-260, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28341621

RESUMEN

Muscle atrophy is a hallmark of cancer cachexia resulting in impaired function and quality of life and cachexia is the immediate cause of death for 20-40% of cancer patients. Multiple microRNAs (miRNAs) have been identified as being involved in muscle development and atrophy; however, less is known specifically on miRNAs in cancer cachexia. The purpose of this investigation was to examine the miRNA profile of skeletal muscle atrophy induced by cancer cachexia to uncover potential miRNAs involved with this catabolic condition. Phosphate-buffered saline (PBS) or Lewis lung carcinoma cells (LLC) were injected into C57BL/6J mice at 8 wk of age. LLC animals were allowed to develop tumors for 4 wk to induce cachexia. Tibialis anterior muscles were extracted and processed to isolate small RNAs, which were used for miRNA sequencing. Sequencing results were assembled with mature miRNAs, and functions of miRNAs were analyzed by Ingenuity Pathway Analysis. LLC animals developed tumors that contributed to significantly smaller tibialis anterior muscles (18.5%) and muscle cross-sectional area (40%) compared with PBS. We found 371 miRNAs to be present in the muscle above background levels. Of these, nine miRNAs were found to be differentially expressed. Significantly altered groups of miRNAs were categorized into primary functionalities including cancer, cell-to-cell signaling, and cellular development among others. Gene network analysis predicted specific alterations of factors contributing to muscle size including Akt, FOXO3, and others. These results create a foundation for future research into the sufficiency of targeting these genes to attenuate muscle loss in cancer cachexia.


Asunto(s)
Caquexia/genética , MicroARNs/genética , Músculo Esquelético/patología , Atrofia Muscular/genética , Neoplasias Experimentales/genética , Animales , Caquexia/complicaciones , Caquexia/fisiopatología , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Ratones Endogámicos C57BL , Atrofia Muscular/etiología , Atrofia Muscular/patología , Neoplasias Experimentales/complicaciones
11.
Am J Physiol Endocrinol Metab ; 313(6): E651-E662, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-28811293

RESUMEN

Pharmacological activation of the glucagon-like peptide-1 receptor (GLP-1R) in the ventromedial hypothalamus (VMH) reduces food intake. Here, we assessed whether suppression of food intake by GLP-1R agonists (GLP-1RA) in this region is dependent on AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR). We found that pharmacological inhibition of glycolysis, and thus activation of AMPK, in the VMH attenuates the anorectic effect of the GLP-1R agonist exendin-4 (Ex4), indicating that glucose metabolism and inhibition of AMPK are both required for this effect. Furthermore, we found that Ex4-mediated anorexia in the VMH involved mTOR but not acetyl-CoA carboxylase, two downstream targets of AMPK. We support this by showing that Ex4 activates mTOR signaling in the VMH and Chinese hamster ovary (CHO)-K1 cells. In contrast to the clear acute pharmacological impact of the these receptors on food intake, knockdown of the VMH Glp1r conferred no changes in energy balance in either chow- or high-fat-diet-fed mice, and the acute anorectic and glucose tolerance effects of peripherally dosed GLP-1RA were preserved. These results show that the VMH GLP-1R regulates food intake by engaging key nutrient sensors but is dispensable for the effects of GLP-1RA on nutrient homeostasis.


Asunto(s)
Ingestión de Alimentos/fisiología , Alimentos , Receptor del Péptido 1 Similar al Glucagón/fisiología , Sensación/fisiología , Núcleo Hipotalámico Ventromedial/fisiología , Acetil-CoA Carboxilasa/metabolismo , Adenilato Quinasa/metabolismo , Animales , Composición Corporal/efectos de los fármacos , Células CHO , Cricetulus , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Exenatida , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Glucólisis/efectos de los fármacos , Homeostasis/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Péptidos/farmacología , Sensación/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Ponzoñas/farmacología , Núcleo Hipotalámico Ventromedial/metabolismo
12.
Exp Physiol ; 102(9): 1194-1207, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28639297

RESUMEN

NEW FINDINGS: What is the central question of this study? What are the individual and combined effects of muscle-specific peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) overexpression and physical activity during high-fat feeding on glucose and exercise tolerance? What is the main finding and its importance? Our main finding is that muscle-specific PGC-1α overexpression provides no protection against lipid-overload pathologies nor does it enhance exercise adaptations. Instead, physical activity, regardless of PGC-1α content, protects against high-fat diet-induced detriments. Activation of muscle autophagy was correlated with exercise protection, suggesting that autophagy might be a mediating factor for exercise-induced protection from lipid overload. The prevalence of glucose intolerance is alarmingly high. Efforts to promote mitochondrial biogenesis through peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) to mitigate glucose intolerance have been controversial. However, physical activity remains a primary means to alleviate the condition. The aim of this study was to determine the combined effects of muscle-specific overexpression of PGC-1α and physical activity on glucose handling during diet-induced obesity. Wild-type (WT, ∼20) and PGC-1α muscle transgenic (MCK-PGC-1α, ∼20) mice were given a Western diet (WD) at 8 weeks age and allowed to consume food ab libitum throughout the study. At 12 weeks of age, all animals were divided into sedentary (SED) or voluntary wheel running (VWR) interventions. At 7, 11 and 15 weeks of age, animals underwent glucose tolerance tests (GTT) and graded exercise tests (GXT). At 16 weeks of age, tissues were collected. At 11 weeks, the MCK-PGC-1α animals had 50% greater glucose tolerance integrated area under the curve compared with WT. However, at 15 weeks, SED animals also had greater GTT integrated area under the curve compared with VWR, regardless of genotype; furthermore, SED animals demonstrated reduced exercise capacity compared with earlier time points, which was not seen in VWR animals. Voluntary distance run per day was correlated with GTT in VWR-WT, but not VWR-MCK-PGC-1α mice. Voluntary wheel running and genotype independently resulted in a greater LC3II/LC3I ratio, suggesting enhanced autophagosome formation, which was correlated with exercise-induced improvements in GTT. In conclusion, artificially increasing mitochondrial content does not protect from lipid-induced pathologies nor does it augment exercise adaptations. Physical activity ameliorates the effects of lipid overload-induced glucose intolerance, an effect that appears to be related to enhanced activation of autophagy.


Asunto(s)
Autofagia/fisiología , Glucosa/metabolismo , Obesidad/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Condicionamiento Físico Animal/fisiología , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mitocondrias/metabolismo , Actividad Motora/fisiología , Músculo Esquelético/metabolismo
13.
Exerc Sport Sci Rev ; 45(4): 217-222, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28704221

RESUMEN

Dopaminergic signaling differences in the nucleus accumbens (NAcc) seemingly predispose rats to adopt different physical activity behaviors. Physical activity behavior also may be regulated through peripheral mechanisms (i.e., muscle and fat derived as well as hormonal signals). We hypothesize that physical activity behavior is regulated by the convergence of central and peripheral mechanisms onto the NAcc.


Asunto(s)
Neuronas Dopaminérgicas/fisiología , Actividad Motora , Núcleo Accumbens/fisiología , Animales , Conducta Animal , Ratas , Transducción de Señal
14.
BMC Psychiatry ; 17(1): 238, 2017 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-28673279

RESUMEN

BACKGROUND: Given the complex nature of symptom presentation and medication regimens, psychiatric clinics may benefit from additional tools to personalize treatments. Utilizing pharmacogenetic information may be helpful in assessing unique responses to therapy. We report herein a case of wearing-off phenomena during treatment with aripiprazole long-acting injectable (LAI) and a proof of concept strategy of how pharmacogenetic information may be used to assess possible genetic factors and also hypothesize potential mechanisms for further study. CASE PRESENTATION: A 51-year-old African American male with schizoaffective disorder was referred to a psychiatric clinic for medication management. After unsuccessful trials of multiple antipsychotics, oral aripiprazole was initiated (up to 30 mg/day) and transitioned to aripiprazole LAI with symptom improvement. At a high dose of aripiprazole LAI (400 mg Q3wks), the patient experienced breakthrough symptoms approximately 3 days prior to his next injection. Various considerations were examined to explain his atypical dose requirements, including but not limited to pharmacogenetic influences. Pharmacogenetic testing ruled out genetic influences on drug metabolism but noted a -141C Del variant in the dopamine-D2 receptor (DRD2) gene associated in prior studies of poor-response to antipsychotics. At this time, a new formulation, aripiprazole lauroxil, was explored due to its availability in higher dose options. Transition to the new formulation (882 mg Q4wks) greatly improved and stabilized the patient's symptoms with no breakthrough psychosis. Comparable daily dose equivalents were achieved with two different formulations due to the Q3wks vs Q4wks dosing strategies, although the two agents have some differences in pharmacokinetic profiles. CONCLUSIONS: We report a case of a patient experiencing wearing-off symptoms with aripiprazole LAI who benefited from switching to aripiprazole lauroxil. Pharmacogenetic testing revealed normal activity for relevant metabolism pathways but a DRD2 -141C variant that may influence brain D2 expression and antipsychotic responsiveness. The clinical utility of DRD2 information and what to do with genotyping results has not been previously addressed, despite availability on clinical test panels. Our case report suggests further investigations of altered dosing strategies and receptor genotype sensitivities to pharmacokinetic factors may be helpful in understanding symptom re-emergence observed in some patients taking LAI antipsychotics.


Asunto(s)
Antipsicóticos/administración & dosificación , Aripiprazol/administración & dosificación , Trastornos Psicóticos/tratamiento farmacológico , Esquizofrenia/tratamiento farmacológico , Preparaciones de Acción Retardada , Esquema de Medicación , Humanos , Inyecciones , Masculino , Persona de Mediana Edad , Farmacogenética
15.
J Cell Biochem ; 117(8): 1775-87, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26683117

RESUMEN

Insulin resistant diabetes, currently at epidemic levels in developed countries, begins in the skeletal muscle and is linked to altered protein turnover. microRNAs downregulate targeted mRNA translation decreasing the amount of translated protein, thereby regulating many cellular processes. Regulation of miRNAs and their function in skeletal muscle insulin resistance is largely unexplored. The purpose of this study was to identify the effects of insulin resistance on contents of skeletal muscle miRNAs with potential functions in protein turnover. We examined miRs -1, -16, -23, -27, -133a, -133b, and -206 in muscles of Zucker rats. miR-1 was 5- to 10-fold greater in obesity, whereas miRs-16 and -133b were repressed ∼50% in obese compared to lean rats, with no other alterations in miRNA contents. miR-16 correlated to protein synthesis in lean, but not obese rats. miR-16 reduction by lipid overload was verified in-vivo by diet-induced obesity and in-vitro using a diacylglycerol analog. A role for miR-16 in protein turnover of skeletal myocytes was established using transient overexpression and anti-miR inhibition. miR-16 overexpression resulted in lower protein synthesis (puromycin incorporation, ∼25-50%), mTOR (∼25%), and p70S6K1 (∼40%) in starved and insulin stimulated myoblasts. Conversely, anti-miR-16 increased basal protein synthesis (puromycin incorporation, ∼75%), mTOR (∼100%), and p70S6K1 (∼100%). Autophagy was enhanced by miR-16 overexpression (∼50% less BCL-2, ∼100% greater LC3II/I, ∼50% less p62) and impaired with miR-16 inhibition (∼45% greater BCL-2, ∼25% less total LC3, ∼50% greater p62). This study demonstrates reduced miR-16 during insulin resistance and establishes miR-16 control of protein accretion in skeletal muscle. J. Cell. Biochem. 117: 1775-1787, 2016. © 2015 Wiley Periodicals, Inc.


Asunto(s)
Autofagia , Resistencia a la Insulina , MicroARNs/metabolismo , Proteínas Musculares/metabolismo , Mioblastos Esqueléticos/metabolismo , Obesidad/metabolismo , Animales , MicroARNs/genética , Proteínas Musculares/genética , Obesidad/genética , Ratas , Ratas Zucker
16.
Cult Health Sex ; 17(10): 1155-73, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26043841

RESUMEN

In order to examine whether pornography consumption is associated with risky sexual behaviour among emerging adults, we examined two large samples of those who reported hooking up in the past 12 months (combined n =  1216). Pornography use was associated with a higher likelihood of having a penetrative hookup; a higher incidence of intoxication during hookups for men (but a lower incidence of intoxication during hookups for women); increasing levels of intoxication during hookups for men but decreasing levels of intoxication for women; and a higher likelihood of being in the riskiest category of having a penetrative hookup, without a condom, while intoxicated. For each of these outcomes, our point estimates for Study 2 fell within the 95% confidence intervals from Study 1. Controlling for trait self-control, binge drinking frequency, broader problematic patterns of alcohol use, openness to experience, and attitudes toward casual sex did not change the pattern of results. Implications for interventions to reduce sexual risk are discussed.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Coito/psicología , Condones/estadística & datos numéricos , Literatura Erótica/psicología , Asunción de Riesgos , Estudiantes/psicología , Sexo Inseguro/psicología , Consumo de Bebidas Alcohólicas/epidemiología , Femenino , Humanos , Masculino , Autoimagen , Factores Sexuales , Parejas Sexuales , Estudiantes/estadística & datos numéricos , Sexo Inseguro/estadística & datos numéricos , Erosión del Cuello del Útero , Adulto Joven
17.
J Physiol ; 592(10): 2119-35, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24665095

RESUMEN

We compared the nucleus accumbens (NAc) transcriptomes of generation 8 (G8), 34-day-old rats selectively bred for low (LVR) versus high voluntary running (HVR) behaviours in rats that never ran (LVR(non-run) and HVR(non-run)), as well as in rats after 6 days of voluntary wheel running (LVR(run) and HVR(run)). In addition, the NAc transcriptome of wild-type Wistar rats was compared. The purpose of this transcriptomics approach was to generate testable hypotheses as to possible NAc features that may be contributing to running motivation differences between lines. Ingenuity Pathway Analysis and Gene Ontology analyses suggested that 'cell cycle'-related transcripts and the running-induced plasticity of dopamine-related transcripts were lower in LVR versus HVR rats. From these data, a hypothesis was generated that LVR rats might have less NAc neuron maturation than HVR rats. Follow-up immunohistochemistry in G9-10 LVR(non-run) rats suggested that the LVR line inherently possessed fewer mature medium spiny (Darpp-32-positive) neurons (P < 0.001) and fewer immature (Dcx-positive) neurons (P < 0.001) than their G9-10 HVR counterparts. However, voluntary running wheel access in our G9-10 LVRs uniquely increased their Darpp-32-positive and Dcx-positive neuron densities. In summary, NAc cellularity differences and/or the lack of running-induced plasticity in dopamine signalling-related transcripts may contribute to low voluntary running motivation in LVR rats.


Asunto(s)
Conducta Animal/fisiología , Actividad Motora/fisiología , Proteínas del Tejido Nervioso/metabolismo , Neuronas/fisiología , Núcleo Accumbens/fisiología , Carrera/fisiología , Volición/fisiología , Animales , Proteína Doblecortina , Femenino , Regulación del Desarrollo de la Expresión Génica/fisiología , Humanos , Plasticidad Neuronal/fisiología , Neuronas/citología , Núcleo Accumbens/citología , Ratas , Ratas Endogámicas
19.
Cureus ; 16(1): e52220, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38348013

RESUMEN

Thrombocytopenia, a condition characterized by low platelet counts, can arise from various causes, including autoimmune diseases. Immune thrombocytopenia (ITP), a diagnosis made by excluding other possible causes, is categorized as primary or secondary, with primary ITP being idiopathic and secondary ITP associated with infections or autoimmune conditions. This study highlights a unique instance of severe thrombocytopenia triggered by Helicobacter pylori infection.

20.
Clin Pharmacol Ther ; 115(5): 1033-1043, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38117180

RESUMEN

Atomoxetine (ATX) is a non-stimulant used to treat attention-deficit/hyperactivity disorder (ADHD) and systemic exposure is highly variable due to polymorphic cytochrome P450 2D6 (CYP2D6) activity. The objective of this study was to characterize the time course of ATX and metabolites (4-hydroxyatomoxetine (4-OH); N-desmethylatomoxetine (NDA); and 2-carboxymethylatomoxetine (2-COOH)) exposure following oral ATX dosing in children with ADHD to support individualized dosing. A nonlinear mixed-effect modeling approach was used to analyze ATX, 4-OH, and NDA plasma and urine, and 2-COOH urine profiles obtained over 24-72 hours from children with ADHD (n = 23) following a single oral ATX dose. Demographics and CYP2D6 activity score (AS) were evaluated as covariates. Simulations were performed to explore the ATX dosing in subjects with various CYP2D6 AS. A simultaneous pharmacokinetic modeling approach was used in which a model for ATX, 4-OH, and NDA in plasma and urine, and 2-COOH in urine was developed. Plasma ATX, 4-OH, and NDA were modeled using two-compartment models with first-order elimination. CYP2D6 AS was a significant determinant of ATX apparent oral clearance (CL/F), fraction metabolized to 4-OH, and systemic exposure of NDA. CL/F of ATX varied almost 7-fold across the CYP2D6 AS groups: AS 2: 20.02 L/hour; AS 1: 19.00 L/hour; AS 0.5: 7.47 L/hour; and AS 0: 3.10 L/hour. The developed model closely captures observed ATX, 4-OH, and NDA plasma and urine, and 2-COOH urine profiles. Application of the model shows the potential for AS-based dosing recommendations for improved individualized dosing.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Propilaminas , Niño , Adolescente , Humanos , Clorhidrato de Atomoxetina/uso terapéutico , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Citocromo P-450 CYP2D6 , Éteres Fenílicos/uso terapéutico , Inhibidores de Captación Adrenérgica
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