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It is well known that the neuropeptide Y (NPY)/agouti-related peptide (AgRP) neurons increase appetite and decrease thermogenesis. Previous studies demonstrated that optogenetic and/or chemogenetic manipulations of NPY/AgRP neuronal activity alter food intake and/or energy expenditure (EE). However, little is known about intrinsic molecules regulating NPY/AgRP neuronal excitability to affect long-term metabolic function. Here, we found that the G protein-gated inwardly rectifying K+ (GIRK) channels are key to stabilize NPY/AgRP neurons and that NPY/AgRP neuron-selective deletion of the GIRK2 subunit results in a persistently increased excitability of the NPY/AgRP neurons. Interestingly, increased body weight and adiposity observed in the NPY/AgRP neuron-selective GIRK2 knockout mice were due to decreased sympathetic activity and EE, while food intake remained unchanged. The conditional knockout mice also showed compromised adaptation to coldness. In summary, our study identified GIRK2 as a key determinant of NPY/AgRP neuronal excitability and driver of EE in physiological and stress conditions.
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Adiposidade , Proteína Relacionada com Agouti , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G , Obesidade , Animais , Camundongos , Proteína Relacionada com Agouti/genética , Peso Corporal , Camundongos Knockout , Neurônios , Peptídeos , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genéticaRESUMO
OBJECTIVE: Low-level somatic mosaicism in the brain has been shown to be a major genetic cause of intractable focal epilepsy. However, how a relatively few mutation-carrying neurons are able to induce epileptogenesis at the local network level remains poorly understood. METHODS: To probe the origin of epileptogenesis, we measured the excitability of neurons with MTOR mutation and nearby nonmutated neurons recorded by whole-cell patch-clamp and array-based electrodes comparing the topographic distribution of mutation. Computational simulation is used to understand neural network-level changes based on electrophysiological properties. To examine the underlying mechanism, we measured inhibitory and excitatory synaptic inputs in mutated neurons and nearby neurons by electrophysiological and histological methods using the mouse model and postoperative human brain tissue for cortical dysplasia. To explain non-cell-autonomous hyperexcitability, an inhibitor of adenosine kinase was injected into mice to enhance adenosine signaling and to mitigate hyperactivity of nearby nonmutated neurons. RESULTS: We generated mice with a low-level somatic mutation in MTOR presenting spontaneous seizures. The seizure-triggering hyperexcitability originated from nonmutated neurons near mutation-carrying neurons, which proved to be less excitable than nonmutated neurons. Interestingly, the net balance between excitatory and inhibitory synaptic inputs onto mutated neurons remained unchanged. Additionally, we found that inhibition of adenosine kinase, which affects adenosine metabolism and neuronal excitability, reduced the hyperexcitability of nonmutated neurons. INTERPRETATION: This study shows that neurons carrying somatic mutations in MTOR lead to focal epileptogenesis via non-cell-autonomous hyperexcitability of nearby nonmutated neurons. ANN NEUROL 2021;90:285-299.
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Epilepsias Parciais/genética , Epilepsias Parciais/fisiopatologia , Malformações do Desenvolvimento Cortical/genética , Malformações do Desenvolvimento Cortical/fisiopatologia , Serina-Treonina Quinases TOR/genética , Adolescente , Animais , Criança , Pré-Escolar , Eletroencefalografia/métodos , Epilepsias Parciais/diagnóstico por imagem , Feminino , Humanos , Masculino , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , GravidezRESUMO
It is well known that melanocortin-4 receptors (MC4Rs) and central melanocortin pathways regulate food intake, energy expenditure, and glucose homeostasis. Importantly, MC4R deficiency is the most common monogenic cause of human obesity. Interestingly, MC4Rs expressed by distinct central nuclei are responsible for the different physiological function of MC4R stimulation. In addition, MC4Rs activate multiple intracellular and/or synaptic signaling molecules for the regulation of neuronal circuits. Therefore, MC4Rs and the downstream signal molecules are plausible targets for development of novel therapeutics against obesity and obesity-related metabolic disorders. In this review, we discuss recent findings on the neuronal circuits and signaling molecules that are responsible for MC4R control energy balance and autonomic function. Further, we review status of MC4R agonists as novel therapeutics for obesity syndrome. We believe that comprehensive understanding of signaling molecules involved in MC4R control of neuronal circuits will help to design MC4R agonists as safe and effective anti-obesity drugs.
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Neurônios/fisiologia , Obesidade/tratamento farmacológico , Receptor Tipo 4 de Melanocortina/fisiologia , Animais , Humanos , Ligantes , Obesidade/fisiopatologia , Receptor Tipo 4 de Melanocortina/agonistas , Transmissão Sináptica , SíndromeRESUMO
Thyroid cancer is a common endocrine malignancy with increasing incidence globally. Although most cases can be treated effectively, some cases are more aggressive and have a higher risk of mortality. Inhibiting RET and BRAF kinases has emerged as a potential therapeutic strategy for the treatment of thyroid cancer, particularly in cases of advanced or aggressive disease. However, the development of resistance mechanisms may limit the efficacy of these kinase inhibitors. Therefore, developing precise strategies to target thyroid cancer cell metabolism and overcome resistance is a critical area of research for advancing thyroid cancer treatment. In the field of cancer therapeutics, researchers have explored combinatorial strategies involving dual metabolic inhibition and metabolic inhibitors in combination with targeted therapy, chemotherapy, and immunotherapy to overcome the challenge of metabolic plasticity. This review highlights the need for new therapeutic approaches for thyroid cancer and discusses promising metabolic inhibitors targeting thyroid cancer. It also discusses the challenges posed by metabolic plasticity in the development of effective strategies for targeting cancer cell metabolism and explores the potential advantages of combined metabolic targeting.
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Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Reprogramação Celular , Terapia de Alvo Molecular , Reprogramação MetabólicaRESUMO
Mitochondrial stress and the dysregulated mitochondrial unfolded protein response (UPRmt) are linked to various diseases, including metabolic disorders, neurodegenerative diseases, and cancer. Mitokines, signaling molecules released by mitochondrial stress response and UPRmt, are crucial mediators of inter-organ communication and influence systemic metabolic and physiological processes. In this review, we provide a comprehensive overview of mitokines, including their regulation by exercise and lifestyle interventions and their implications for various diseases. The endocrine actions of mitokines related to mitochondrial stress and adaptations are highlighted, specifically the broad functions of fibroblast growth factor 21 and growth differentiation factor 15, as well as their specific actions in regulating inter-tissue communication and metabolic homeostasis. Finally, we discuss the potential of physiological and genetic interventions to reduce the hazards associated with dysregulated mitokine signaling and preserve an equilibrium in mitochondrial stress-induced responses. This review provides valuable insights into the mechanisms underlying mitochondrial regulation of health and disease by exploring mitokine interactions and their regulation, which will facilitate the development of targeted therapies and personalized interventions to improve health outcomes and quality of life.
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Doenças Metabólicas , Qualidade de Vida , Humanos , Mitocôndrias/metabolismo , Doenças Metabólicas/terapia , Doenças Metabólicas/metabolismo , Transdução de SinaisRESUMO
BACKGRUOUND: Aging leads to sarcopenia, which is characterized by reduced muscle mass and strength. Many factors, including altered muscle protein turnover, diminished neuromuscular function, hormonal changes, systemic inflammation, and the structure and composition of muscle fibers, play a crucial role in age-related muscle decline. This study explored differences in muscle fiber types contributing to overall muscle function decline in aging, focusing on individuals with hip fractures from falls. METHODS: A pilot study at Chungnam National University Hospital collected muscle biopsies from hip fracture patients aged 20 to 80 undergoing surgical treatment. Muscle biopsies from the vastus lateralis and gluteus maximus were obtained during hip arthroplasty or internal fixation. Handgrip strength, calf and thigh circumference, and bone mineral density were evaluated in individuals with hip fractures from falls. We analyzed the relationships between each clinical characteristic and muscle fiber type. RESULTS: In total, 26 participants (mean age 67.9 years, 69.2% male) were included in this study. The prevalence of sarcopenia was 53.8%, and that of femoral and lumbar osteoporosis was 19.2% and 11.5%, respectively. Vastus lateralis analysis revealed an age-related decrease in type IIx fibers, a higher proportion of type IIa fibers in women, and an association between handgrip strength and type IIx fibers in men. The gluteus maximus showed no significant correlations with clinical parameters. CONCLUSION: This study identified complex associations between age, sex, handgrip strength, and muscle fiber composition in hip fracture patients, offering insights crucial for targeted interventions combating age-related muscle decline and improving musculoskeletal health.
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Fraturas do Quadril , Músculo Quadríceps , Sarcopenia , Humanos , Masculino , Feminino , Idoso , Fraturas do Quadril/patologia , Sarcopenia/patologia , Músculo Quadríceps/patologia , Pessoa de Meia-Idade , Projetos Piloto , Idoso de 80 Anos ou mais , Força da Mão , Adulto , Densidade Óssea , Fibras Musculares Esqueléticas/patologia , Fibras Musculares Esqueléticas/metabolismo , Adulto Jovem , Envelhecimento/fisiologia , Envelhecimento/patologia , Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Rápida/metabolismoRESUMO
Objectives: Chronic low-grade inflammation is widely recognized as a pathophysiological defect contributing to ß-cell failure in type 2 diabetes mellitus (T2DM). Statin therapy is known to ameliorate CD8+ T cell senescence, a mediator of chronic inflammation. However, the additional immunomodulatory roles of ezetimibe are not fully understood. Therefore, we investigated the effect of statin or statin/ezetimibe combination treatment on T cell senescence markers. Methods: In this two-group parallel and randomized controlled trial, we enrolled 149 patients with T2DM whose low-density lipoprotein cholesterol (LDL-C) was 100 mg/dL or higher. Patients were randomly assigned to either the rosuvastatin group (N=74) or the rosuvastatin/ezetimibe group (N=75). The immunophenotype of peripheral blood mononuclear cells and metabolic profiles were analyzed using samples from baseline and post-12 weeks of medication. Results: The fractions of CD8+CD57+ (senescent CD8+ T cells) and CD4+FoxP3+ (Treg) significantly decreased after intervention in the rosuvastatin/ezetimibe group (-4.5 ± 14.1% and -1.2 ± 2.3%, respectively), while these fractions showed minimal change in the rosuvastatin group (2.8 ± 9.4% and 1.4 ± 1.5%, respectively). The degree of LDL-C reduction was correlated with an improvement in HbA1c (R=0.193, p=0.021). Changes in the CD8+CD57+ fraction positively correlated with patient age (R=0.538, p=0.026). Notably, the fraction change in senescent CD8+ T cells showed no significant relationship with changes in either HbA1c (p=0.314) or LDL-C (p=0.592). Finally, the ratio of naïve to memory CD8+ T cells increased in the rosuvastatin/ezetimibe group (p=0.011), but not in the rosuvastatin group (p=0.339). Conclusions: We observed a reduction in senescent CD8+ T cells and an increase in the ratio of naive to memory CD8+ T cells with rosuvastatin/ezetimibe treatment. Our results demonstrate the immunomodulatory roles of ezetimibe in combination with statins, independent of improvements in lipid or HbA1c levels.
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Anticolesterolemiantes , Azetidinas , Diabetes Mellitus Tipo 2 , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Humanos , Rosuvastatina Cálcica/uso terapêutico , Ezetimiba/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , LDL-Colesterol , Anticolesterolemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Leucócitos Mononucleares , Hipercolesterolemia/tratamento farmacológico , Azetidinas/uso terapêutico , Fluorbenzenos/uso terapêutico , Pirimidinas , Sulfonamidas/uso terapêutico , Quimioterapia Combinada , Resultado do Tratamento , Inflamação/tratamento farmacológico , Linfócitos TRESUMO
The SUVmax is a measure of FDG uptake and is related with tumor aggressiveness in thyroid cancer, however, its association with molecular pathways is unclear. Here, we investigated the relationship between SUVmax and gene expression profiles in 80 papillary thyroid cancer (PTC) patients. We conducted an analysis of DEGs and enriched pathways in relation to SUVmax and tumor size. SUVmax showed a positive correlation with tumor size and correlated with glucose metabolic process. The genes that indicate thyroid differentiation, such as SLC5A5 and TPO, were negatively correlated with SUVmax. Unsupervised analysis revealed that SUVmax positively correlated with DNA replication(r = 0.29, p = 0.009), pyrimidine metabolism(r = 0.50, p < 0.0001) and purine metabolism (r = 0.42, p = 0.0001). Based on subgroups analysis, we identified that PSG5, TFF3, SOX2, SL5A5, SLC5A7, HOXD10, FER1L6, and IFNA1 genes were found to be significantly associated with tumor aggressiveness. Both high SUVmax PTMC and macro-PTC are enriched in pathways of DNA replication and cell cycle, however, gene sets for purine metabolic pathways are enriched only in high SUVmax macro-PTC but not in high SUVmax PTMC. Our findings demonstrate the molecular characteristics of high SUVmax tumor and metabolism involved in tumor growth in differentiated thyroid cancer.
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Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Transcriptoma , Humanos , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/metabolismo , Feminino , Masculino , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo , Pessoa de Meia-Idade , Adulto , Fluordesoxiglucose F18 , Regulação Neoplásica da Expressão Gênica , Idoso , Perfilação da Expressão Gênica , Carga Tumoral/genéticaRESUMO
Objective: Active surveillance (AS) is generally accepted as an alternative to immediate surgery for papillary thyroid carcinoma (PTC) measuring ≤1.0 cm (cT1a) without risk factors. This study investigated the clinicopathologic characteristics of PTCs measuring ≤2.0 cm without cervical lymph node metastasis (cT1N0) by tumor size group to assess the feasibility of AS for PTCs between 1.0 cm and 1.5 cm (cT1b≤1.5). Design: This study enrolled clinically T1N0 patients with preoperative ultrasonography information (n= 935) from a cohort of 1259 patients who underwent lobectomy and were finally diagnosed with PTC from June 2020 to March 2022. Results: The cT1b≤1.5 group (n = 171; 18.3 %) exhibited more lymphatic invasion and occult central lymph node (LN) metastasis with a higher metastatic LN ratio than the cT1a group (n = 719; 76.9 %). However, among patients aged 55 years or older, there were no significant differences in occult central LN metastasis and metastatic LN ratio between the cT1a, cT1b≤1.5, and cT1b>1.5 groups. Multivariate regression analyses revealed that occult central LN metastasis was associated with age, sex, tumor size, extrathyroidal extension, and lymphatic invasion in patients under 55, while in those aged 55 or older, it was associated only with age and lymphatic invasion. Conclusion: For PTC patients aged 55 years or older with cT1b≤1.5, AS could be a viable option due to the absence of a significant relationship between tumor size and occult central LN.
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Carcinoma Papilar , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Estudos de Viabilidade , Conduta Expectante , Carcinoma Papilar/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , UltrassonografiaRESUMO
Muscle wasting in end-stage renal disease (ESRD) is an escalating issue due to the increasing global prevalence of ESRD and its significant clinical impact, including a close association with elevated mortality risk. The phenomenon of muscle wasting in ESRD, which exceeds the rate of muscle loss observed in the normal aging process, arises from multifactorial processes. This review paper aims to provide a comprehensive understanding of muscle wasting in ESRD, covering its epidemiology, underlying molecular mechanisms, and current and emerging therapeutic interventions. It delves into the assessment techniques for muscle mass and function, before exploring the intricate metabolic and molecular pathways that lead to muscle atrophy in ESRD patients. We further discuss various strategies to mitigate muscle wasting, including nutritional, pharmacological, exercise, and physical modalities intervention. This review seeks to provide a solid foundation for future research in this area, fostering a deeper understanding of muscle wasting in ESRD, and paving the way for the development of novel strategies to improve patient outcomes. [BMB Reports 2023; 56(8): 426-438].
Assuntos
Falência Renal Crônica , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/metabolismo , Falência Renal Crônica/terapia , Atrofia Muscular , Exercício Físico , Músculos/metabolismoRESUMO
The spinal cord is a part of the central nervous system located within the spinal canal of the vertebrae. Here, we present a protocol to prepare mouse spinal cord sections for patch-clamp and histology experiments. We describe steps for isolating spinal cord from the spinal canal and obtaining acute slices for patch-clamp experiments. For histology experiments, we detail fixing spinal cord for cryosectioning and imaging. This protocol provides procedures to assess neuronal activity and protein expression of sympathetic preganglionic neurons. For complete details on the use and execution of this protocol, please refer to Ju et al.1.
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Background: Sarcopenia, which is strongly associated with mortality and quality of life, occurs in up to 40% of hemodialysis patients. Here, we investigated the preventive effects of leucine-enriched amino acid supplementation and resistance exercise in non-sarcopenic hemodialysis patients, and characterized the biochemical and immunophenotypic profiles of those who benefited from the intervention. Methods: Twenty-two patients on maintenance hemodialysis at our hospital were enrolled in this single center, prospective, single-arm pilot trial. For the first 12 weeks, the subjects were administered a total of 6 g of leucine per day. Three grams were supplied via capsules, and the remaining three grams were provided via beverages containing macro- and micro- nutrients, such as 10 µg of vitamin D and 290 mg of calcium. The supplements were not provided for the next 12 weeks. Muscle mass, grip strength, and physical performance were measured using the bioimpedance analyzer (BIA), handgrip strength (HGS), and short physical performance battery (SPPB) protocols, respectively, at baseline, 12 weeks, and 24 weeks. In addition, serum biochemistry, immunophenotype of peripheral blood mononuclear cells, and nutritional status was assessed at the three time points. Those who showed 5% or more improvement in parameters were defined as responders, otherwise, as non-responders (ClinicalTrials.gov identification number: NCT04927208). Results: Twenty-one out of twenty-two patients (95.4%) showed improvement in at least one or more parameters among muscle mass, grip strength, and physical performance. After 12 weeks of intervention, skeletal muscle index was increased in 14 patients (63.6%), and grip strength was improved in 7 patients (31.8%). Baseline grip strength lower than 35.0 kg was the strongest predictor of improvement in grip strength (AUC 0.933 from ROC curve). Grip strength showed a significant increase in females than males (7.6 ± 8.2 vs. -1.6 ± 7.2%, p = 0.03), in age over 60 than under 60 (5.3 ± 6.2 vs. -1.4 ± 9.1%, p = 0.04), and in higher (≥95%) than lower (<95%) exercise compliance (6.8 ± 7.7 vs. -3.2 ± 6.4%, p = 0.004). In SPPB study, gait speed and sit-to-stand time was improved in 13 patients (59.1%) and 14 patients (63.6%), respectively. Baseline hemoglobin lower than 10.5 g/dl and hematocrit lower than 30.8% were predictor of improvement in the sit-to-stand time (AUC 0.862 and 0.848, respectively). Serum biochemistry results showed that, compared to non-responders, responders in muscle mass had lower baseline monocyte fraction (8.4 ± 1.9 vs. 6.9 ± 1.1%, p = 0.03), and responders in grip strength had lower baseline total protein (6.7 ± 0.4 vs. 6.4 ± 0.3 g/dL, p = 0.04). Immunophenotypic analysis found that the intervention tended to increase the naïve/memory CD8+ T cell ratio (from 1.2 ± 0.8 to 1.4 ± 1.1, p = 0.07). Conclusion: Leucine-enriched amino acid supplementation and resistance exercise induced significant improvement in muscle mass, strength, and physical function in subpopulation of the non-sarcopenic hemodialysis patients. Those who benefited from the intervention were old-age females with lower baseline grip strength or lower hemoglobin or hematocrit, and who have good exercise compliance. Therefore, we propose that the intervention will help to prevent sarcopenia in selected patients on maintenance hemodialysis.
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BACKGROUND: A decade ago, systemic inflammation became widely recognized as an etiology of type 2 diabetes mellitus (T2DM) and complications thereof. Senescent CD8â +â T cells of T2DM patients exhibit increased secretion of pro-inflammatory cytokines and enhanced expression of cytotoxic molecules, contributing to systemic inflammation. Recently, many anti-inflammatory roles played by statins and ezetimibe (cholesterol-lowering drugs) have been reported. We will explore the effects of statin/ezetimibe therapy on CD8â +â T cell senescence in patients with T2DM and hypercholesterolemia. METHODS: This 2-group, parallel, randomized, controlled clinical trial will recruit 108 subjects with T2DM and low-density lipoprotein-cholesterol (LDL-C) levelsâ ≥100 mg/dL and randomly assign them to rosuvastatin/ezetimibe and rosuvastatin groups at a 1:1 ratio. Blood samples will be drawn at baseline and after 12 weeks of medication. The primary outcomes will be the LDL-C-lowering effects after 12 weeks. The secondary outcomes will be changes in the senescent (CD28â -â CD57+) CD8â +â T cell proportions; the levels of circulating pro-inflammatory cytokines, cytotoxic molecules, interleukin-1, transforming growth factor-ß, fasting glucose, and HbA1c; and biochemical indices of kidney, liver, and muscle function. Symptoms and signs of predictable adverse events (myopathy and hepatitis) will be routinely monitored. DISCUSSION: We will evaluate the effects of statin/ezetimibe on CD8â +â T cell senescence. Statin/ezetimibe may exert a beneficial immunomodulatory effect.
Assuntos
Diabetes Mellitus Tipo 2 , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Humanos , Ezetimiba/uso terapêutico , Rosuvastatina Cálcica/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , LDL-Colesterol , Linfócitos T CD8-Positivos , Citocinas , Inflamação , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Cancer therapies targeting genetic alterations are a topic of great interest in the field of thyroid cancer, which frequently harbors mutations in the RAS, RAF, and RET genes. Unfortunately, U.S. Food and Drug Administration-approved BRAF inhibitors have relatively low therapeutic efficacy against BRAF-mutant thyroid cancer; in addition, the cancer often acquires drug resistance, which prevents effective treatment. Recent advances in genomics and transcriptomics are leading to a more complete picture of the range of mutations, both driver and messenger, present in thyroid cancer. Furthermore, our understanding of cancer suggests that oncogenic mutations drive tumorigenesis and induce rewiring of cancer cell metabolism, which promotes survival of mutated cells. Synthetic lethality (SL) is a method of neutralizing mutated genes that were previously considered untargetable by traditional genotype-targeted treatments. Because these metabolic events are specific to cancer cells, we have the opportunity to develop new therapies that target tumor cells specifically without affecting healthy tissue. Here, we describe developments in metabolism-based cancer therapy, focusing on the concept of metabolic SL in thyroid cancer. Finally, we discuss the essential implications of metabolic reprogramming and its role in the future direction of SL for thyroid cancer.
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Mutações Sintéticas Letais , Neoplasias da Glândula Tireoide , Humanos , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Estados UnidosRESUMO
Melanocortin-4 receptors (MC4Rs) expressed by the central nervous system are essential regulators of energy homeostasis, and Mc4r mutation is the most common cause of human monogenic obesity. Notably, patients with obesity carrying Mc4r mutations are protected against obesity-induced hypertension, and MC4R agonists elevate blood pressure (BP). Although increased sympathetic tone by MC4Rs is suggested to underlie this phenotype, the detailed mechanisms remain unclear. Here, we investigate how MC4Rs regulate the sympathetic preganglionic neurons and find that MC4Rs activate these neurons via the protein kinase A-dependent activation of the transient receptor potential vanilloid 1 (TRPV1) channel. Importantly, we demonstrate that the inhibition of TRPV1 prevents MC4R-induced elevation of BP but does not affect MC4R-induced anorexia. We further show that TRPV1 is responsible for MC4R-dependent activation of the sympathetic preganglionic neurons by high-fat diet. Together, our results provide insight into how MC4Rs regulate sympathetic function.
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Obesidade , Receptor Tipo 4 de Melanocortina , Humanos , Pressão Sanguínea/fisiologia , Receptor Tipo 4 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/metabolismo , Obesidade/metabolismo , Neurônios/metabolismo , Dieta Hiperlipídica , Melanocortinas/metabolismo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismoRESUMO
BACKGRUOUND: An excess of thyroid hormones in Graves' disease (GD) has profound effects on systemic energy metabolism that are currently partially understood. In this study, we aimed to provide a comprehensive understanding of the metabolite changes that occur when patients with GD transition from hyperthyroidism to euthyroidism with methimazole treatment. METHODS: Eighteen patients (mean age, 38.6±14.7 years; 66.7% female) with newly diagnosed or relapsed GD attending the endocrinology outpatient clinics in a single institution were recruited between January 2019 and July 2020. All subjects were treated with methimazole to achieve euthyroidism. We explored metabolomics by performing liquid chromatography-mass spectrometry analysis of plasma samples of these patients and then performed multivariate statistical analysis of the metabolomics data. RESULTS: Two hundred metabolites were measured before and after 12 weeks of methimazole treatment in patients with GD. The levels of 61 metabolites, including palmitic acid (C16:0) and oleic acid (C18:1), were elevated in methimazole-naïve patients with GD, and these levels were decreased by methimazole treatment. The levels of another 15 metabolites, including glycine and creatinine, were increased after recovery of euthyroidism upon methimazole treatment in patients with GD. Pathway analysis of metabolomics data showed that hyperthyroidism was closely related to aminoacyl-transfer ribonucleic acid biosynthesis and branched-chain amino acid biosynthesis pathways. CONCLUSION: In this study, significant variations of plasma metabolomic patterns that occur during the transition from hyperthyroidism to euthyroidism were detected in patients with GD via untargeted metabolomics analysis.
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Doença de Graves , Hipertireoidismo , Humanos , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Masculino , Metimazol/uso terapêutico , Antitireóideos/uso terapêutico , Hipertireoidismo/tratamento farmacológico , Doença de Graves/tratamento farmacológico , Hormônios TireóideosRESUMO
OBJECTIVE: This study aimed to determine whether completion thyroidectomy is necessary based on long-term follow-up oncological results according to various clinical and pathological characteristics of patients with papillary thyroid carcinoma (PTC) who underwent lobectomy. MATERIALS AND METHODS: We enrolled 1815 patients with PTC who underwent thyroid lobectomy from January 2003 to December 2014. Various clinical and pathological characteristics were reviewed retrospectively, and clinicopathologic characteristics and recurrence rates were analyzed. RESULTS: Eighty-two (4.5%) patients showed locoregional recurrence during the average 10.2-year follow-up period. There was no significant difference in tumor size, multifocality, lymphovascular invasion (LVI), microscopic or strap muscle-extrathyroidal extension, and central neck lymph node (LN) micrometastasis between the recurrence and non-recurrence groups. The gross strap muscle-extrathyroidal extension group was associated with older age (p < 0.001), larger tumor size (p < 0.001), more capsular invasion (p < 0.001), and more LVI (p < 0.001) than the negative extrathyroidal extension group; there was no significant difference in recurrence between the groups (p = 0.096). Patients with five or more central LN micrometastases were associated with younger age (p = 0.006), larger tumor size (p = 0.04), and presence of LVI (p = 0.033) than patients with less than five central LN metastases; there was no significant difference in recurrence between the groups (p = 0.867). All patients with recurrence were cured through reoperation after recurrence was confirmed. CONCLUSION: After thyroid lobectomy, PTC patients with multifocality, LVI, extrathyroidal extension to the strap muscles, or five or more central LN micrometastases may not require immediate completion thyroidectomy.
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Carcinoma Papilar , Neoplasias da Glândula Tireoide , Carcinoma Papilar/patologia , Carcinoma Papilar/cirurgia , Humanos , Linfonodos/patologia , Linfonodos/cirurgia , Músculos/patologia , Micrometástase de Neoplasia , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodosRESUMO
Isolated hypogonadotropic hypogonadism (IHH) is known to decrease bone mineral density due to deficiency of sex steroid hormone. Graves' disease is also an important cause of secondary osteoporosis. However, IHH does not preclude the development of primary hyperthyroidism caused by Graves' disease, leading to more severe osteoporosis rapidly. Here, we describe the first case of 35-year-old Asian female patient with IHH accompanied by Graves' disease and osteoporosis-induced multiple fractures. Endocrine laboratory findings revealed preserved anterior pituitary functions except for secretion of gonadotropins and showed primary hyperthyroidism with positive autoantibodies. Sella magnetic resonance imaging showed slightly small sized pituitary gland without mass lesion. Dual energy X-ray absorptiometry revealed severe osteoporosis in lumbar spine and femur neck of the patient. Plain film radiography of the pelvis and shoulder revealed a displaced and nondisplaced fracture, respectively. After surgical fixation with screws for the femoral fracture, the patient was treated with antithyroid medication, calcium, and vitamin D until now and has been recovering fairly well. We report a patient of IHH with Graves' disease and multiple fractures that is a first case in Korea.