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1.
Public Health Nurs ; 41(2): 318-324, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38246855

RESUMEN

Vaccination is vital in combating infectious diseases, including COVID-19. Nevertheless, vaccine hesitancy poses a substantial obstacle to achieving high vaccination rates. This study investigated the determinants of vaccine hesitancy using behavioral change theories and proposes a comprehensive conceptual framework to address this challenge.The paper conducted a review of several behavior change theories relevant to understanding vaccine hesitancy. The health belief model (HBM) highlighted the importance of individuals' perceptions of the effectiveness of health behaviors and their perceived susceptibility to illness. The social cognitive model (SCT) underscored the role of personal experiences, environmental factors, and social support in shaping health behaviors. The theory of reasoned action and planned behavior (TRA) suggested that attitudes and subjective norms are crucial in determining behavioral intentions. The transtheoretical model (TTM) outlined stages of behavior change, while the socio-ecological model (SEM) considered factors at individual, relationship, community, and societal levels. Comprehending vaccine hesitancy is essential for developing effective strategies to promote vaccine acceptance. This study, which examined vaccine hesitancy through various behavior change theories, sought to shed light on the factors influencing vaccine hesitancy among Filipinos. The resulting conceptual framework offers guidance for future interventions aimed at addressing vaccine hesitancy and ultimately improving vaccination rates.


Asunto(s)
COVID-19 , Vacilación a la Vacunación , Humanos , Conductas Relacionadas con la Salud , Modelo de Creencias sobre la Salud , Intención , Vacunación
2.
Nat Rev Neurosci ; 19(2): 95-105, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29321684

RESUMEN

Obesity represents the single most important risk factor for early disability and death in developed societies, and the incidence of obesity remains at staggering levels. CNS systems that modulate energy intake and expenditure in response to changes in body energy stores serve to maintain constant body adiposity; the adipocyte-derived hormone leptin and its receptor (LEPR) represent crucial regulators of these systems. As in the case of insulin resistance, a variety of mechanisms (including feedback inhibition, inflammation, gliosis and endoplasmic reticulum stress) have been proposed to interfere with leptin action and impede the systems that control body energy homeostasis to promote or maintain obesity, although the relative importance and contribution of each of these remain unclear. However, LEPR signalling may be increased (rather than impaired) in common obesity, suggesting that any obesity-associated defects in leptin action must result from lesions somewhere other than the initial LEPR signal. It is also possible that increased LEPR signalling could mediate some of the obesity-associated changes in hypothalamic function.


Asunto(s)
Peso Corporal/fisiología , Homeostasis/fisiología , Leptina/metabolismo , Obesidad/metabolismo , Receptores de Leptina/metabolismo , Animales , Metabolismo Energético/fisiología , Humanos , Transducción de Señal/fisiología
4.
Ther Drug Monit ; 40(4): 394-400, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29750738

RESUMEN

BACKGROUND: Inpatient tacrolimus therapeutic drug monitoring (TDM) lacks standardized guidelines. In this study, the authors analyzed variability in the preanalytical phase of the inpatient tacrolimus TDM process at their institution. METHODS: Patients receiving tacrolimus (twice-daily formulation) and tacrolimus laboratory analysis were included in the study. Times of tacrolimus administration and laboratory study collection were extracted, and time distribution plots for each step in the inpatient TDM process were generated. RESULTS: Trough levels were drawn appropriately in 25.9% of the cases. Timing between doses was consistent, with 91.9% of the following dose administrations occurring 12 ± 2 hours after the previous dose. Only 38.1% of the drug administrations occurred within 1 hour of laboratory study collection. Tacrolimus-related patient safety events were reported at a rate of 1.9 events per month while incorrect timing of TDM sample collection occurred approximately 200 times per month. Root cause analysis identified a TDM process marked by a lack of communication and coordination of drug administration and TDM sample collection. Extrapolating findings nationwide, we estimate $22 million in laboratory costs wasted annually. CONCLUSIONS: Based on this large single-center study, the authors concluded that the inpatient TDM process is prone to timing errors, thus is financially wasteful, and at its worst harmful to patients due to clinical decisions being made on the basis of unreliable data. Further work is needed on systems solutions to better align the laboratory study collection and drug administration processes.


Asunto(s)
Recolección de Muestras de Sangre/estadística & datos numéricos , Esquema de Medicación , Monitoreo de Drogas/estadística & datos numéricos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Tacrolimus/sangre , Costos de los Medicamentos/estadística & datos numéricos , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/sangre , Inmunosupresores/economía , Pacientes Internos , Michigan/epidemiología , Estudios Retrospectivos , Tacrolimus/efectos adversos , Tacrolimus/economía , Factores de Tiempo , Trasplantes/economía
5.
Eur J Ophthalmol ; 34(2): NP25-NP27, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37787169

RESUMEN

PURPOSE: To report a case of neovascularization against autologous grafts after simple limbal epithelial transplantation (SLET) despite successful corneal epithelialization, as well as its subsequent regression without intervention. METHODS: A case report and review of the literature. RESULTS: A 52-year-old woman underwent uncomplicated autologous SLET for asymmetric limbal stem cell deficiency (LSCD) in the left eye. One month after the surgery, the patient had successful adherence of the graft and corneal epithelialization; however, new neovascularization developed in the left eye towards the graft sites. With only a slow taper of topical prednisolone acetate and polymyxin b/trimethoprim, the neovascularization regressed to ghost vessels over the following three months with improvement of her LSCD symptoms and increased clarity of her cornea. CONCLUSION: The limbus does not enjoy relative immune privilege like other parts of the eye; therefore, autologous limbal stem cell transplantation (along with the minimal immune response generated) is valuable for restoration of the ocular surface. Here, we describe neovascularization against autologous donor grafts despite an otherwise uncomplicated surgery and expected epithelialization course. Inflammation-mediated angiogenesis likely initiated the neovascularization, suggesting that immune mediators of inflammation may be inadvertently part of the graft tissue in bilateral LSCD.


Asunto(s)
Enfermedades de la Córnea , Trasplante de Córnea , Epitelio Corneal , Quemaduras Oculares , Limbo de la Córnea , Humanos , Femenino , Persona de Mediana Edad , Enfermedades de la Córnea/cirugía , Córnea , Trasplante Autólogo , Metaplasia , Inflamación , Trasplante de Células Madre
6.
Ophthalmic Surg Lasers Imaging Retina ; 55(1): 51-54, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38189803

RESUMEN

Acute exudative polymorphous vitelliform maculopathy (AEPVM) has recently been identified as a paraneoplastic manifestation of various cancers. Yet, the first reported cases of AEPVM in the literature were reported in seemingly healthy individuals. It is not clear whether those individuals harbored unidentified mutations or occult cancers, or truly represented a separate subset of AEPVM. Here, we report two cases of mutation-negative, autoantibody-positive non-paraneoplastic AEPVM. We present multimodal ocular imaging to demonstrate the presentation of this subset of AEPVM. [Ophthalmic Surg Lasers Imaging Retina 2024;55:51-54.].


Asunto(s)
Degeneración Macular , Neoplasias , Humanos , Autoanticuerpos , Bestrofinas , Ojo
7.
Public Health Pract (Oxf) ; 7: 100476, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38463217

RESUMEN

Objective: The Business Process Outsourcing (BPO) industry in the Philippines has experienced substantial growth, making a significant contribution to the country's economy. However, concerns about work-related health and safety issues have emerged, necessitating effective workplace health promotion strategies for BPO employees. Study design: An integrative review of relevant literature was conducted to explore workplace health promotion in the BPO sector. Methods: The search included quantitative, qualitative, and mixed-method studies, pertinent laws, policies, news articles, and reports published between 2000 and 2022. The scope was intentionally broad to encompass a diverse range of relevant evidence related to workplace health in this field. Articles published both in the English and Filipino languages were considered. Results: Findings revealed that BPO workers face risks related to physical and psychological stress, sleep disturbances, and occupational diseases owing to the unique challenges inherent to the nature of their jobs. While there are existing occupational health and labor laws, compliance among BPO companies remains a problem, and only a few organizations offer comprehensive wellness programs. Building upon the available evidence, a conceptual framework was developed to provide guidance for enhancing workplace health promotion initiatives specifically designed for BPOs in the country. Conclusion: Workplace health promotion is vital to warrant the health and safety of BPO workers. This study offers evidence-based recommendations for implementing effective well-being strategies, highlighting the importance of collaboration among employers, employees, and society to prioritize employee health in the workplace.

8.
Am J Ophthalmol Case Rep ; 32: 101941, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37915729

RESUMEN

Purpose: To report a case of recurrent retinoblastoma following transpupillary thermotherapy (TTT) with development of scleral ectasia, as well as their successful treatment with intra-arterial chemotherapy. Observations: A 15-month-old girl with bilateral retinoblastoma presented with recurrent retinoblastoma and associated scleral ectasia with concern for extraocular extension after receiving multiple round of systemic chemotherapy and TTT. Given her negative systemic evaluation, decision was made to pursue intra-arterial chemotherapy. After completion of six rounds of 3-agent intra-arterial chemotherapy, the recurrent retinoblastoma had completely regressed and the scleral ectasia had improved and fibrosed. Conclusions and importance: The sclera is classically viewed as hyperthermy-resistant to TTT. Here, we describe scleral ectasia due to aggressive TTT with recurrence of the retinoblastoma. Our treatment with intra-arterial chemotherapy not only caused complete regression of the recurrent retinoblastoma, but it also contributed to the stabilization and improvement of the weakened scleral.

9.
Ophthalmol Retina ; 7(11): 948-953, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37399975

RESUMEN

OBJECTIVE: To measure the total costs and reimbursements associated with standard and complex pars plana vitrectomy using time-driven activity-based costing (TDABC). DESIGN: Economic analysis at a single academic institution. SUBJECTS: Patients who underwent standard or complex pars plana vitrectomy (PPV; Current Procedural Terminology codes 67108 and 67113) at the University of Michigan in the calendar year 2021. METHODS: Process flow mapping for standard and complex PPVs was used to determine the operative components. The internal anesthesia record system was used to calculate time estimates, and financial calculations were constructed from published literature and internal sources. A TDABC analysis was used to determine the costs of standard and complex PPVs. Average reimbursement was based on Medicare rates. MAIN OUTCOME MEASURES: The primary outcomes were the total costs for standard and complex PPVs and the resulting net margin at current Medicare reimbursement levels. The secondary outcomes were the differential in surgical times, costs, and margin for standard and complex PPV. RESULTS: Over the 2021 calendar year, a total of 270 standard and 142 complex PPVs were included in the analysis. Complex PPVs were associated with significantly increased anesthesia time (52.28 minutes; P < 0.001), operating room time (51.28 minutes; P < 0.0001), surgery time (43.64 minutes; P < 0.0001), and postoperative time (25.95 minutes; P < 0.0001). The total day-of-surgery costs were $5154.59 and $7852.38 for standard and complex PPVs, respectively. Postoperative visits incurred an additional cost of $327.84 and $353.86 for standard and complex PPV, respectively. The institution-specific facility payments were $4505.50 and $4935.14 for standard and complex PPV, respectively. Standard PPV yielded a net negative margin of -$976.93, whereas complex PPV yielded a net negative margin of -$3271.10. CONCLUSIONS: This analysis demonstrated that Medicare reimbursement is inadequate in covering the costs of PPV for retinal detachment, with a particularly large negative margin for more complex cases. These findings demonstrate that additional steps may be necessary to mitigate adverse economic incentives so that patients continue to have timely access to care to achieve optimal visual outcomes after retinal detachment. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.


Asunto(s)
Desprendimiento de Retina , Anciano , Humanos , Estados Unidos , Desprendimiento de Retina/cirugía , Desprendimiento de Retina/etiología , Vitrectomía/métodos , Curvatura de la Esclerótica/métodos , Agudeza Visual , Medicare
10.
Ophthalmic Surg Lasers Imaging Retina ; 53(11): 644-646, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36378617

RESUMEN

Perfluorocarbon liquid (PFCL) is an important adjunct in pars plana vitrectomy (PPV) for complex retinal detachment (RD). Complete removal of PFCL is critical to prevent retinal inflammation and cellular toxicity, but removal is not risk-free. We report a case of a new postoperative onset paracentral visual field defect after PPV with PFCL use for treatment of a macula-on RD. We present pre- and postoperative imaging that suggests a likely perioperative iatrogenic cause. [Ophthalmic Surg Lasers Imaging Retina 2022;53:644-646.].


Asunto(s)
Fluorocarburos , Desprendimiento de Retina , Humanos , Vitrectomía/efectos adversos , Vitrectomía/métodos , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/cirugía , Desprendimiento de Retina/etiología , Campos Visuales , Agudeza Visual , Fluorocarburos/efectos adversos , Trastornos de la Visión/cirugía , Enfermedad Iatrogénica , Estudios Retrospectivos
11.
J Biol Chem ; 285(45): 34348-54, 2010 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-20729202

RESUMEN

In the host immune system, leukocytes are often exposed to multiple inflammation inducers. NF-κB is of considerable importance in leukocyte function because of its ability to activate the transcription of many proinflammatory immediate-early genes. Tremendous efforts have been made toward understanding how NF-κB is activated by various inducers. However, most research on NF-κB regulation has been focused on understanding how NF-κB is activated by a single inducer. This is unlike the situation in the human immune system where multiple inflammation inducers, including both exogenous and endogenous mediators, are present concurrently. We now present evidence that the formylated peptide f-Met-Leu-Phe (fMLP), a bacterial chemoattractant, synergizes with TNFα to induce NF-κB activation and the resultant inflammatory response in vitro and in vivo. The mechanism of synergistic activation of NF-κB by bacterial fMLP and TNFα may be involved in the induction of RelA acetylation, which is regulated by p38 MAPK. Thus, this study provides direct evidence for the synergistic induction of NF-κB-dependent inflammatory responses by both exogenous and endogenous inducers. The ability of fMLP to synergize with TNFα and activate NF-κB represents a novel and potentially important mechanism through which bacterial fMLP not only attracts leukocytes but also directly contributes to inflammation by synergizing with the endogenous mediator TNFα.


Asunto(s)
Mediadores de Inflamación/farmacología , Leucocitos/metabolismo , N-Formilmetionina Leucil-Fenilalanina/farmacología , FN-kappa B/metabolismo , Factor de Transcripción ReIA/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Acetilación/efectos de los fármacos , Animales , Línea Celular , Sinergismo Farmacológico , Humanos , Inflamación/inmunología , Inflamación/metabolismo , Mediadores de Inflamación/agonistas , Mediadores de Inflamación/inmunología , Leucocitos/inmunología , Ratones , N-Formilmetionina Leucil-Fenilalanina/agonistas , N-Formilmetionina Leucil-Fenilalanina/inmunología , FN-kappa B/inmunología , Factor de Transcripción ReIA/inmunología , Factor de Necrosis Tumoral alfa/agonistas , Factor de Necrosis Tumoral alfa/inmunología , Proteínas Quinasas p38 Activadas por Mitógenos/inmunología
12.
J Immunol ; 182(9): 5810-5, 2009 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-19380829

RESUMEN

We have reported that the bacterial LPS induces the activation of NF-kappaB and inflammatory cytokine gene expression and that this requires the activity of small GTPase, RhoA. In this study, we show that an atypical protein kinase C isozyme, PKCzeta, associates functionally with RhoA and that PKCzeta acts as a signaling component downstream of RhoA. Stimulation of monocytes and macrophages with LPS resulted in PKCzeta activation and that inhibition of PKCzeta activity blocks both LPS-stimulated activation of NF-kappaB and IL-1beta gene expression. Our results also indicate that transforming growth factor beta-activated kinase 1 acts as a signaling component downstream of PKCzeta in cytokine gene transcription stimulated by LPS in human peripheral blood monocytes and macrophages. The specificity of this response suggests an important role for the Rho GTPase/PKCzeta/transforming growth factor beta-activated kinase 1/NF-kappaB pathway in host defense and in proinflammatory cytokine synthesis induced by bacterial LPS.


Asunto(s)
Lipopolisacáridos/fisiología , Macrófagos/metabolismo , Monocitos/metabolismo , FN-kappa B/metabolismo , Proteína Quinasa C/fisiología , Animales , Línea Celular , Activación Enzimática/inmunología , Humanos , Isoenzimas/fisiología , Macrófagos/enzimología , Ratones , Monocitos/enzimología , FN-kappa B/sangre , Proteína Quinasa C/sangre , Proteína Quinasa C/metabolismo , Transducción de Señal/inmunología
13.
J Immunol ; 182(4): 2518-24, 2009 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19201908

RESUMEN

A wide variety of stimuli have been shown to induce inflammation, but bacteria products/components are considered the major inducers during bacterial infections. We previously demonstrated that bacterial products/components such as LPS, a glycolipid component of the bacterial outer membrane, and formylated peptides (fMLP), a bacterial-derived peptide, induced proinflammatory cytokine gene expression in human peripheral blood monocytes. We now present evidence that mixtures of bacterial products/components LPS and fMLP behave synergistically in the induction of inflammation in vitro and in vivo. Furthermore, our results indicate that the TLR4 and the IKKbeta-IkappaBalpha signaling pathways are involved in the synergistic induction of inflammatory cytokines. The mechanism of synergistic activation of NF-kappaB is depended on nuclear translocation of p65 and phosphorylation of p65 at both Ser536 and Ser276 sites. These results demonstrate an important role for bacterial products/components from lysed bacteria in the pathogenesis of infectious diseases. We believe that this synergistic induction of inflammation by bacterial products LPS and fMLP represents an important pathogenic mechanism during bacterial infection, which may suggest novel therapeutic strategies or targets to minimize host injury following bacterial infection.


Asunto(s)
Inflamación/inmunología , Lipopolisacáridos/inmunología , Monocitos/inmunología , Receptores de Formil Péptido/inmunología , Transducción de Señal/inmunología , Animales , Western Blotting , Células Cultivadas , Ensayo de Cambio de Movilidad Electroforética , Ensayo de Inmunoadsorción Enzimática , Humanos , Inflamación/microbiología , Interleucina-1beta/biosíntesis , Interleucina-1beta/inmunología , Interleucina-8/inmunología , Ratones , FN-kappa B/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptor Toll-Like 4/inmunología , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/inmunología
14.
Prog Retin Eye Res ; 84: 100940, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33429059

RESUMEN

The prevalence of diabetes has been rising steadily in the past half-century, along with the burden of its associated complications, including diabetic retinopathy (DR). DR is currently the most common cause of vision loss in working-age adults in the United States. Historically, DR has been diagnosed and classified clinically based on what is visible by fundoscopy; that is vasculature alterations. However, recent technological advances have confirmed pathology of the neuroretina prior to any detectable vascular changes. These, coupled with molecular studies, and the positive impact of anti-inflammatory therapeutics in DR patients have highlighted the central involvement of the innate immune system. Reminiscent of the systemic impact of diabetes, immune dysregulation has become increasingly identified as a key element of the pathophysiology of DR by interfering with normal homeostatic systems. This review uses the growing body of literature across various model systems to demonstrate the clear involvement of all three pillars of the immune system: immune-competent cells, mediators, and the complement system. It also demonstrates how the relative contribution of each of these requires more extensive analysis, including in human tissues over the continuum of disease progression. Finally, although this review demonstrates how the complex interactions of the immune system pose many more questions than answers, the intimately connected nature of the three pillars of the immune system may also point to possible new targets to reverse or even halt reverse retinopathy.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Inmunidad Innata , Proteínas del Sistema Complemento , Retinopatía Diabética/inmunología , Humanos , Sistema Inmunológico , Estados Unidos , Trastornos de la Visión
15.
J Clin Med ; 10(6)2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33803590

RESUMEN

Diabetic retinal disease (DRD) remains the most common cause of vision loss in adults of working age. Progress on the development of new therapies for DRD has been limited by the complexity of the human eye, which constrains the utility of traditional research techniques, including animal and tissue culture models-a problem shared by those in the field of kidney disease research. By contrast, significant progress in the study of diabetic kidney disease (DKD) has resulted from the successful employment of systems biology approaches. Systems biology is widely used to comprehensively understand complex human diseases through the unbiased integration of genetic, environmental, and phenotypic aspects of the disease with the functional and structural manifestations of the disease. The application of a systems biology approach to DRD may help to clarify the molecular basis of the disease and its progression. Acquiring this type of information might enable the development of personalized treatment approaches, with the goal of discovering new therapies targeted to an individual's specific DRD pathophysiology and phenotype. Furthermore, recent efforts have revealed shared and distinct pathways and molecular targets of DRD and DKD, highlighting the complex pathophysiology of these diseases and raising the possibility of therapeutics beneficial to both organs. The objective of this review is to survey the current understanding of DRD pathophysiology and to demonstrate the investigative approaches currently applied to DKD that could promote a more thorough understanding of the structure, function, and progression of DRD.

16.
Commun Biol ; 4(1): 245, 2021 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-33627778

RESUMEN

Acquired and inherited retinal disorders are responsible for vision loss in an increasing proportion of individuals worldwide. Photoreceptor (PR) death is central to the vision loss individuals experience in these various retinal diseases. Unfortunately, there is a lack of treatment options to prevent PR loss, so an urgent unmet need exists for therapies that improve PR survival and ultimately, vision. The retina is one of the most energy demanding tissues in the body, and this is driven in large part by the metabolic needs of PRs. Recent studies suggest that disruption of nutrient availability and regulation of cell metabolism may be a unifying mechanism in PR death. Understanding retinal cell metabolism and how it is altered in disease has been identified as a priority area of research. The focus of this review is on the recent advances in the understanding of PR metabolism and how it is critical to reduction-oxidation (redox) balance, the outer retinal metabolic ecosystem, and retinal disease. The importance of these metabolic processes is just beginning to be realized and unraveling the metabolic and redox pathways integral to PR health may identify novel targets for neuroprotective strategies that prevent blindness in the heterogenous group of retinal disorders.


Asunto(s)
Reprogramación Celular , Metabolismo Energético , Células Fotorreceptoras/metabolismo , Enfermedades de la Retina/metabolismo , Trastornos de la Visión/metabolismo , Visión Ocular , Animales , Muerte Celular , Humanos , Metaboloma , Metabolómica , Células Fotorreceptoras/patología , Enfermedades de la Retina/patología , Enfermedades de la Retina/fisiopatología , Enfermedades de la Retina/terapia , Trastornos de la Visión/patología , Trastornos de la Visión/fisiopatología , Trastornos de la Visión/terapia
17.
Endocrinology ; 162(6)2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33834205

RESUMEN

The paraventricular nucleus of the hypothalamus (PVH) is a heterogeneous collection of neurons that play important roles in modulating feeding and energy expenditure. Abnormal development or ablation of the PVH results in hyperphagic obesity and defects in energy expenditure whereas selective activation of defined PVH neuronal populations can suppress feeding and may promote energy expenditure. Here, we characterize the contribution of calcitonin receptor-expressing PVH neurons (CalcRPVH) to energy balance control. We used Cre-dependent viral tools delivered stereotaxically to the PVH of CalcR2Acre mice to activate, silence, and trace CalcRPVH neurons and determine their contribution to body weight regulation. Immunohistochemistry of fluorescently-labeled CalcRPVH neurons demonstrates that CalcRPVH neurons are largely distinct from several PVH neuronal populations involved in energy homeostasis; these neurons project to regions of the hindbrain that are implicated in energy balance control, including the nucleus of the solitary tract and the parabrachial nucleus. Acute activation of CalcRPVH neurons suppresses feeding without appreciably augmenting energy expenditure, whereas their silencing leads to obesity that may be due in part due to loss of PVH melanocortin-4 receptor signaling. These data show that CalcRPVH neurons are an essential component of energy balance neurocircuitry and their function is important for body weight maintenance. A thorough understanding of the mechanisms by which CalcRPVH neurons modulate energy balance might identify novel therapeutic targets for the treatment and prevention of obesity.


Asunto(s)
Metabolismo Energético/fisiología , Núcleo Hipotalámico Paraventricular/fisiología , Receptores de Calcitonina/fisiología , Animales , Ingestión de Alimentos/fisiología , Metabolismo Energético/genética , Conducta Alimentaria/fisiología , Homeostasis/fisiología , Hipotálamo/metabolismo , Hipotálamo/fisiología , Masculino , Ratones , Ratones Transgénicos , Neuronas/metabolismo , Neuronas/fisiología , Núcleo Hipotalámico Paraventricular/metabolismo , Receptor de Melanocortina Tipo 4/genética , Receptor de Melanocortina Tipo 4/metabolismo , Receptor de Melanocortina Tipo 4/fisiología , Receptores de Calcitonina/genética , Receptores de Calcitonina/metabolismo
18.
Nat Commun ; 12(1): 5175, 2021 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-34462445

RESUMEN

Calcitonin receptor (Calcr)-expressing neurons of the nucleus tractus solitarius (NTS; CalcrNTS cells) contribute to the long-term control of food intake and body weight. Here, we show that Prlh-expressing NTS (PrlhNTS) neurons represent a subset of CalcrNTS cells and that Prlh expression in these cells restrains body weight gain in the face of high fat diet challenge in mice. To understand the relationship of PrlhNTS cells to hypothalamic feeding circuits, we determined the ability of PrlhNTS-mediated signals to overcome enforced activation of AgRP neurons. We found that PrlhNTS neuron activation and Prlh overexpression in PrlhNTS cells abrogates AgRP neuron-driven hyperphagia and ameliorates the obesity of mice deficient in melanocortin signaling or leptin. Thus, enhancing Prlh-mediated neurotransmission from the NTS dampens hypothalamically-driven hyperphagia and obesity, demonstrating that NTS-mediated signals can override the effects of orexigenic hypothalamic signals on long-term energy balance.


Asunto(s)
Obesidad/metabolismo , Hormona Liberadora de Prolactina/metabolismo , Núcleo Solitario/metabolismo , Animales , Apetito , Dieta , Ingestión de Alimentos , Metabolismo Energético , Femenino , Humanos , Hipotálamo/metabolismo , Leptina/metabolismo , Masculino , Melanocortinas/metabolismo , Ratones , Ratones Endogámicos C57BL , Neuronas/metabolismo , Obesidad/genética , Obesidad/fisiopatología , Obesidad/psicología , Hormona Liberadora de Prolactina/genética , Receptores de Calcitonina/genética , Receptores de Calcitonina/metabolismo
19.
Nat Med ; 27(6): 1088-1096, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34045736

RESUMEN

Mutations in the melanocortin 4 receptor gene (MC4R) are associated with obesity but little is known about the prevalence and impact of such mutations throughout human growth and development. We examined the MC4R coding sequence in 5,724 participants from the Avon Longitudinal Study of Parents and Children, functionally characterized all nonsynonymous MC4R variants and examined their association with anthropometric phenotypes from childhood to early adulthood. The frequency of heterozygous loss-of-function (LoF) mutations in MC4R was ~1 in 337 (0.30%), considerably higher than previous estimates. At age 18 years, mean differences in body weight, body mass index and fat mass between carriers and noncarriers of LoF mutations were 17.76 kg (95% CI 9.41, 26.10), 4.84 kg m-2 (95% CI 2.19, 7.49) and 14.78 kg (95% CI 8.56, 20.99), respectively. MC4R LoF mutations may be more common than previously reported and carriers of such variants may enter adult life with a substantial burden of excess adiposity.


Asunto(s)
Peso Corporal/genética , Predisposición Genética a la Enfermedad , Obesidad/genética , Receptor de Melanocortina Tipo 4/genética , Adolescente , Adulto , Niño , Preescolar , Heterocigoto , Humanos , Lactante , Recién Nacido , Mutación con Pérdida de Función/genética , Masculino , Obesidad/epidemiología , Obesidad/patología , Fenotipo , Reino Unido , Adulto Joven
20.
Cell Metab ; 31(2): 301-312.e5, 2020 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-31955990

RESUMEN

To understand hindbrain pathways involved in the control of food intake, we examined roles for calcitonin receptor (CALCR)-containing neurons in the NTS. Ablation of NTS Calcr abrogated the long-term suppression of food intake, but not aversive responses, by CALCR agonists. Similarly, activating CalcrNTS neurons decreased food intake and body weight but (unlike neighboring CckNTS cells) failed to promote aversion, revealing that CalcrNTS neurons mediate a non-aversive suppression of food intake. While both CalcrNTS and CckNTS neurons decreased feeding via projections to the PBN, CckNTS cells activated aversive CGRPPBN cells while CalcrNTS cells activated distinct non-CGRP PBN cells. Hence, CalcrNTS cells suppress feeding via non-aversive, non-CGRP PBN targets. Additionally, silencing CalcrNTS cells blunted food intake suppression by gut peptides and nutrients, increasing food intake and promoting obesity. Hence, CalcrNTS neurons define a hindbrain system that participates in physiological energy balance and suppresses food intake without activating aversive systems.


Asunto(s)
Ingestión de Alimentos , Metabolismo Energético , Neuronas/metabolismo , Receptores de Calcitonina/fisiología , Núcleo Solitario/metabolismo , Animales , Peso Corporal , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/citología , Núcleo Solitario/citología
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