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1.
BMC Musculoskelet Disord ; 24(1): 869, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37940935

RESUMEN

BACKGROUND: The Kellgren-Lawrence (KL) grading system is the most widely used method to classify the severity of osteoarthritis (OA) of the knee. However, due to ambiguity of terminology, the KL system showed inferior inter- and intra-observer reliability. For a more reliable evaluation, we recently developed novel deep learning (DL) software known as MediAI-OA to extract each radiographic feature of knee OA and to grade OA severity based on the KL system. METHODS: This research used data from the Osteoarthritis Initiative for training and validation of MediAI-OA. 44,193 radiographs and 810 radiographs were set as the training data and used as validation data, respectively. This AI model was developed to automatically quantify the degree of joint space narrowing (JSN) of medial and lateral tibiofemoral joint, to automatically detect osteophytes in four regions (medial distal femur, lateral distal femur, medial proximal tibia and lateral proximal tibia) of the knee joint, to classify the KL grade, and present the results of these three OA features together. The model was tested by using 400 test datasets, and the results were compared to the ground truth. The accuracy of the JSN quantification and osteophyte detection was evaluated. The KL grade classification performance was evaluated by precision, recall, F1 score, accuracy, and Cohen's kappa coefficient. In addition, we defined KL grade 2 or higher as clinically significant OA, and accuracy of OA diagnosis were obtained. RESULTS: The mean squared error of JSN rate quantification was 0.067 and average osteophyte detection accuracy of the MediAI-OA was 0.84. The accuracy of KL grading was 0.83, and the kappa coefficient between the AI model and ground truth was 0.768, which demonstrated substantial consistency. The OA diagnosis accuracy of this software was 0.92. CONCLUSIONS: The novel DL software known as MediAI-OA demonstrated satisfactory performance comparable to that of experienced orthopedic surgeons and radiologists for analyzing features of knee OA, KL grading and OA diagnosis. Therefore, reliable KL grading can be performed and the burden of the radiologist can be reduced by using MediAI-OA.


Asunto(s)
Aprendizaje Profundo , Osteoartritis de la Rodilla , Osteofito , Humanos , Osteoartritis de la Rodilla/diagnóstico por imagen , Reproducibilidad de los Resultados , Programas Informáticos
2.
Eur J Radiol ; 168: 111016, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37742371

RESUMEN

PURPOSE: The morphometry of the hepatic portal vein is of clinical importance, particularly in pre-operative assessments, surgical management, and diagnoses of liver conditions. This systematic review and meta-analysis aimed to characterize the morphometry of the normal portal vein in both pediatric and adult patients. METHODS: The study, conducted using the PRISMA guidelines and registered with PROSPERO, utilized the MEDLINE, EMBASE, SCOPUS and Web of Science databases up to May 2020, and updated to May 2023. All studies reporting extractable data on diameter, length, and cross-sectional area (CSA) of the main, left, and right portal veins (PV, LPV, RPV, respectively) were included. The AQUA Tool was used to assess the quality of the included studies. Data analysis included subgroup analyses based on geographical location, sex, age, and imaging modality. RESULTS: A total of 122 studies with 11,637 subjects were eligible for inclusion. Overall, the pooled mean diameter of the PV (PVD) was 10.09 mm (95% CI: 9.56-10.62). Significant differences in diameter were found between pediatric (6.60 mm; 95% CI: 5.38-7.82) and adult (10.72 mm; 95% CI: 10.25-11.19) subjects. Additionally, there was a significantly larger PVD measurement from computed tomography (CT) than other imaging modalities: CT, 13.28 mm (95% CI: 11.71-14.84); magnetic resonance imaging (MRI), 10.50 mm (95% CI: 9.35-11.66) and ultrasound (US), 9.81 mm (95% CI: 9.47-10.16). The mean diameters of the LPV and RPV were 8.27 mm (95% CI: 6.78-9.77) and 8.33 mm (95% CI: 6.70-9.95), respectively. Mean PV length in adults is 48.63 mm (95% CI: 35.63-61.64). Mean CSA of the PV was 1.09 cm2. CONCLUSIONS: The study obtained aim to improve the understanding of portal vein anatomy, especially with relevance to surgical interventions of the liver in both pediatric and adult patients. Measurements from ultrasound imaging closely approximates the generated pooled PVD mean for pediatric and adult patients. CT imaging, however, significantly exceeded the established 13 mm threshold for adults. For pediatric patients, a threshold of 8 mm is proposed as a diagnostic upper limit for a normal PVD. Although not significant, the PVD decreased from the portal confluence towards its bifurcation.


Asunto(s)
Hepatopatías , Vena Porta , Humanos , Adulto , Niño , Vena Porta/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Imagen por Resonancia Magnética
4.
Toxicol Res ; 38(4): 577-589, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36277358

RESUMEN

Quisqualis indica L. of Combretaceae family is a traditional medicine that is widely used for various gastrointestinal discomfort including stomach pain, constipation, and digestive problem. In this study, the potential repeated dose toxicity and genotoxicity of a standardized Quisqualis indica L. extract (HU033) were determined under good laboratory practice conditions. For the repeated dose toxicity test, HU033 was orally administered to Sprague-Dawley (SD) rats at doses of 500, 1000, and 2000 mg/kg/day for 13 consecutive weeks. The genotoxicity of HU033 was determined with a standard battery of genotoxicity test, including an in vitro bacterial reverse mutation test, an in vitro chromosomal aberration test, and an in vivo micronucleus test. After 13 weeks of repeated dose of HU033 by oral administration, there was no treatment related adverse clinical sign including food consumption, organ weights, and histopathological findings or significant decrement in bodyweight. The no-observed-adverse-effect level of HU033 was higher than 2000 mg/kg in both male and female SD rats. No target organs were identified. In addition, no evidence of HU033 genotoxicity was detected based on results from the bacterial reverse mutation test, chromosomal aberration test, and micronucleus test. Based on results of this study, HU033 could be safely used in food and medical products within the tested dose range.

5.
Diabetologia ; 65(9): 1519-1533, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35616696

RESUMEN

AIMS/HYPOTHESIS: Pancreatic islets depend on cytosolic calcium (Ca2+) to trigger the secretion of glucoregulatory hormones and trigger transcriptional regulation of genes important for islet response to stimuli. To date, there has not been an attempt to profile Ca2+-regulated gene expression in all islet cell types. Our aim was to construct a large single-cell transcriptomic dataset from human islets exposed to conditions that would acutely induce or inhibit intracellular Ca2+ signalling, while preserving biological heterogeneity. METHODS: We exposed intact human islets from three donors to the following conditions: (1) 2.8 mmol/l glucose; (2) 16 mmol/l glucose and 40 mmol/l KCl to maximally stimulate Ca2+ signalling; and (3) 16 mmol/l glucose, 40 mmol/l KCl and 5 mmol/l EGTA (Ca2+ chelator) to inhibit Ca2+ signalling, for 1 h. We sequenced 68,650 cells from all islet cell types, and further subsetted the cells to form an endocrine cell-specific dataset of 59,373 cells expressing INS, GCG, SST or PPY. We compared transcriptomes across conditions to determine the differentially expressed Ca2+-regulated genes in each endocrine cell type, and in each endocrine cell subcluster of alpha and beta cells. RESULTS: Based on the number of Ca2+-regulated genes, we found that each alpha and beta cell cluster had a different magnitude of Ca2+ response. We also showed that polyhormonal clusters expressing both INS and GCG, or both INS and SST, are defined by Ca2+-regulated genes specific to each cluster. Finally, we identified the gene PCDH7 from the beta cell clusters that had the highest number of Ca2+-regulated genes, and showed that cells expressing cell surface PCDH7 protein have enhanced glucose-stimulated insulin secretory function. CONCLUSIONS/INTERPRETATION: Here we use our large-scale, multi-condition, single-cell dataset to show that human islets have cell-type-specific Ca2+-regulated gene expression profiles, some of them specific to subpopulations. In our dataset, we identify PCDH7 as a novel marker of beta cells having an increased number of Ca2+-regulated genes and enhanced insulin secretory function. DATA AVAILABILITY: A searchable and user-friendly format of the data in this study, specifically designed for rapid mining of single-cell RNA sequencing data, is available at https://lynnlab.shinyapps.io/Human_Islet_Atlas/ . The raw data files are available at NCBI Gene Expression Omnibus (GSE196715).


Asunto(s)
Células Secretoras de Insulina , Islotes Pancreáticos , Calcio/metabolismo , Glucosa/metabolismo , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo
6.
Development ; 149(1)2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-35020896

RESUMEN

In early placental development, progenitor cytotrophoblasts (CTB) differentiate along one of two cellular trajectories: the villous or extravillous pathways. CTB committed to the villous pathway fuse with neighboring CTB to form the outer multinucleated syncytiotrophoblast (SCT), whereas CTB committed to the extravillous pathway differentiate into invasive extravillous trophoblasts (EVT). Unfortunately, little is known about the processes controlling human CTB progenitor maintenance and differentiation. To address this, we established a single cell RNA sequencing (scRNA-seq) dataset from first trimester placentas to identify cell states important in trophoblast progenitor establishment, renewal and differentiation. Multiple distinct trophoblast states were identified, representing progenitor CTB, column CTB, SCT precursors and EVT. Lineage trajectory analysis identified a progenitor origin that was reproduced in human trophoblast stem cell organoids. Heightened expression of basal cell adhesion molecule (BCAM) defined this primitive state, where BCAM enrichment or gene silencing resulted in enhanced or diminished organoid growth, respectively. Together, this work describes at high-resolution trophoblast heterogeneity within the first trimester, resolves gene networks within human CTB progenitors and identifies BCAM as a primitive progenitor marker and possible regulator.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Linaje de la Célula , Sistema del Grupo Sanguíneo Lutheran/metabolismo , Trofoblastos/metabolismo , Adulto , Moléculas de Adhesión Celular/genética , Diferenciación Celular , Células Cultivadas , Femenino , Regulación del Desarrollo de la Expresión Génica , Redes Reguladoras de Genes , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/metabolismo , Humanos , Sistema del Grupo Sanguíneo Lutheran/genética , Organoides/citología , Organoides/metabolismo , Trofoblastos/citología
7.
Sci Rep ; 11(1): 18394, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34526546

RESUMEN

Although innate immunity is linked to metabolic health, the effect of leptin signaling in cells from the innate immune system on glucose homeostasis has not been thoroughly investigated. We generated two mouse models using Cre-lox methodology to determine the effect of myeloid cell-specific leptin receptor (Lepr) reconstitution and Lepr knockdown on in vivo glucose metabolism. Male mice with myeloid cell-specific Lepr reconstitution (Lyz2Cre+LeprloxTB/loxTB) had better glycemic control as they aged compared to male mice with whole-body transcriptional blockade of Lepr (Lyz2Cre-LeprloxTB/loxTB). In contrast, Lyz2Cre+LeprloxTB/loxTB females only had a trend for diminished hyperglycemia after a prolonged fast. During glucose tolerance tests, Lyz2Cre+LeprloxTB/loxTB males had a mildly improved plasma glucose profile compared to Cre- controls while Lyz2Cre+LeprloxTB/loxTB females had a similar glucose excursion to their Cre- controls. Myeloid cell-specific Lepr knockdown (Lyz2Cre+Leprflox/flox) did not significantly alter body weight, blood glucose, insulin sensitivity, or glucose tolerance in males or females. Expression of the cytokine interleukin 10 (anti-inflammatory) tended to be higher in adipose tissue of male Lyz2Cre+LeprloxTB/loxTB mice (p = 0.0774) while interleukin 6 (pro-inflammatory) was lower in male Lyz2Cre+Leprflox/flox mice (p < 0.05) vs. their respective controls. In conclusion, reconstitution of Lepr in cells of myeloid lineage has beneficial effects on glucose metabolism in male mice.


Asunto(s)
Glucosa/metabolismo , Leptina/metabolismo , Células Mieloides/metabolismo , Transducción de Señal , Animales , Biomarcadores , Glucemia/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Metabolismo Energético , Técnicas de Silenciamiento del Gen , Homeostasis , Leptina/genética , Masculino , Enfermedades Metabólicas/etiología , Enfermedades Metabólicas/metabolismo , Ratones
8.
World J Orthop ; 11(11): 492-498, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-33269215

RESUMEN

BACKGROUND: Orthopedic physicians typically apply a cast to immobilize a body part that has been injured. There have been no significant structural changes or advances in synthetic casts since the development of the modern cast. The Opencast® is a recently developed type of cast that allows ventilation and direct visual inspection of the skin to avoid cast-related complications. Although this novel cast appears to have more benefits than the conventional synthetic cast, its clinical efficacy and advantages have not been established. AIM: To investigate the clinical efficacy and advantages of the newly developed Opencast® based on patients' perspectives in those with ankle inversion injury. METHODS: A specifically designed questionnaire consisting of 19 items was used to compare patients' opinions and concerns of the Opencast® and the conventional synthetic cast. The items were focused on subjective patient satisfaction, discomfort, and adverse effects while wearing the cast. Patients with an ankle inversion injury diagnosed as a high-grade ankle sprain were enrolled. The subjects were randomized and instructed to fill the questionnaire after wearing a synthetic cast or an Opencast® for 2 wk. They were then required to fill the questionnaire again, after switching to the alternative type of cast for 2 more weeks. RESULTS: A total of 22 subjects participated in the study. The synthetic cast appeared to be more rigid and stable than the Opencast®, but there was no significant difference in the amount of pain relief. The likelihood of adverse effects when wearing the synthetic cast was significantly higher. Patient satisfaction tended to be rated higher after wearing the Opencast®. Opencast® showed more subjective vulnerability than the synthetic cast, but there was no significant difference in the redo rate. Patients were more anxious about removal of the synthetic cast than of the Opencast®. CONCLUSION: The results indicate that the Opencast® could replace the conventional synthetic cast as it offers increased patient satisfaction, which would in turn increase compliance to treatment.

9.
Orthop J Sports Med ; 8(6): 2325967120927481, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32637430

RESUMEN

BACKGROUND: Early osteoarthritis of the knee joint mostly affects the medial compartment, making osteotomy a rational approach to slow the progression of the disease. However, some patients show asymptomatic mild degeneration in the lateral or patellofemoral compartment. PURPOSE: To evaluate the effect of asymptomatic mild lateral or patellofemoral degeneration on the outcomes of medial open wedge high tibial osteotomy (OWHTO) by assessing the outcomes according to the preoperative status of the lateral or patellofemoral degenerative changes. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 114 patients (121 knees) who underwent biplanar OWHTO with second-look arthroscopic surgery and postoperative magnetic resonance imaging (MRI) were retrospectively enrolled. Patients were categorized into 4 groups according to the Osteoarthritis Research Society International (OARSI) and MRI Osteoarthritis Knee Score (MOAKS) classification systems. The International Cartilage Repair Society (ICRS) grade was used to evaluate the preoperative and postoperative cartilage status. Clinical outcomes were assessed by the American Knee Society (AKS) score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and 36-item Short Form Health Survey (SF-36). RESULTS: No degenerative changes in the lateral and patellofemoral compartments of knees (group I) were identified in 51.2% of cases (62 knees). Asymptomatic degenerative changes only in the lateral compartment (group II: OARSI grades 1-3 and MOAKS grades 1-3) were identified in 15.7% of cases (19 knees), changes only in the patellofemoral compartment (group III: OARSI grades 1-3 and MOAKS grades 1-3) were identified in 10.7% of cases (13 knees), and changes in both the lateral and the patellofemoral compartments (group IV) were identified in 22.3% of cases (27 knees). In the medial compartment, there was no significant difference in the improvement of MOAKS and ICRS grades among all groups (P = .813 and .985, respectively). In the lateral and patellofemoral compartments, there was no significant difference in the decline of MOAKS (P = .649 and .421, respectively) and ICRS grades (P = .927 and .676, respectively) among all groups. CONCLUSION: The presence of mild lateral or patellofemoral degenerative changes did not affect the MRI, arthroscopic, and clinical outcomes of OWHTO. However, long-term observations are necessary to draw definitive conclusions as to whether OWHTO can be indicated in such patients without harmful effects.

10.
PLoS One ; 14(8): e0221945, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31454402

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0220073.].

11.
PLoS One ; 14(7): e0220073, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31339908

RESUMEN

BACKGROUND: This study aimed to investigate the effects of walking speed and slope on foot pressure changes in young healthy adults. METHODS: Twenty young healthy adults (mean age 22.4 years, SD 1.2 years; 10 male and 10 female) participated in the study. Dynamic pedobarographic data during treadmill walking were obtained for combinations of three different walking speeds (3.2 km/hr, 4.3 km/hr, and 5.4 km/hr) and 5 different slopes (downhill 8 degrees, downhill 4 degrees, ground walking (0 degree), uphill 4 degrees, and uphill 8 degrees). Pedobarographic data such as the peak pressure and pressure-time integral were measured on five plantar segments: medial forefoot (MFF), lateral forefoot (LFF), medial midfoot (MMF), lateral midfoot (LMF), and heel. Maximum ankle dorsiflexion was also recorded using the Plug in Gait marker set. RESULTS: All participants maintained heel-toe gait in all walking conditions. The peak pressure on the MFF during downhill slope walking was lower than that during ground and uphill walking, whereas the peak pressure on the MFF during uphill slope walking was similar to that during ground walking at each walking speed. The peak pressures on the heel were similar for different walking slopes at each walking speed. The peak pressures on the MFF and heel increased with an increase in walking speed. The pressure-time integral of the MFF did not show significant changes at different walking speeds and slopes. The pressure-time integral of the heel increased with an increase in walking slope and decrease in walking speed. CONCLUSIONS: Different walking speeds and slopes affected the pedobarographic characteristics of young healthy adults. Downhill walking with slower speed appeared to be beneficial to reduce or optimize MFF pressures, while downhill walking at a comfortable speed would be helpful to reduce or optimize heel pressures. The findings of this study have clinical implications in recommending activities to patients with foot pressure-related symptoms and disorders.


Asunto(s)
Pie/fisiología , Velocidad al Caminar , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Presión , Adulto Joven
12.
Sci Rep ; 9(1): 3307, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30824713

RESUMEN

The relative contribution of peripheral and central leptin signalling to the regulation of metabolism and the mechanisms through which leptin affects glucose homeostasis have not been fully elucidated. We generated complementary lines of mice with either leptin receptor (Lepr) knockdown or reconstitution in adipose tissues using Cre-lox methodology. Lepr knockdown mice were modestly lighter and had lower plasma insulin concentrations following an oral glucose challenge compared to controls, despite similar insulin sensitivity. We rendered male mice diabetic using streptozotocin (STZ) and found that upon prolonged leptin therapy, Lepr knockdown mice had an accelerated decrease in blood glucose compared to controls that was associated with higher plasma concentrations of leptin and leptin receptor. Mice with transcriptional blockade of Lepr (LeprloxTB/loxTB) were obese and hyperglycemic and reconstitution of Lepr in adipose tissues of LeprloxTB/loxTB mice resulted in males reaching a higher maximal body weight. Although mice with adipose tissue Lepr reconstitution had lower blood glucose levels at several ages, their plasma insulin concentrations during an oral glucose test were elevated. Thus, attenuation or restoration of Lepr in adipocytes alters the plasma insulin profile following glucose ingestion, modifies the glucose-lowering effect of prolonged leptin therapy in insulin-deficient diabetes, and may modulate weight gain.


Asunto(s)
Tejido Adiposo/metabolismo , Diabetes Mellitus Experimental , Técnicas de Silenciamiento del Gen , Receptores de Leptina , Tejido Adiposo/patología , Animales , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Ratones , Ratones Transgénicos , Receptores de Leptina/genética , Receptores de Leptina/metabolismo
13.
Prev Nutr Food Sci ; 24(4): 492-497, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31915646

RESUMEN

Benign prostatic hyperplasia (BPH) is an age-related disease characterized by prostatic enlargement and is the most common urologic symptoms in elderly men 60 years of age and older. Previously, we documented that 70% ethanol (EtOH) seed extract of Quisqualis indica (QI) attenuates pathological condition of testosterone propionate (TP)-induced BPH rat model via modulation of proliferation and apoptosis of prostate cells. Based on this potential of QI, we produced standardized seed extract of QI (HU-033) in order to prove further mechanisms. In this study, we aimed to suggest further mechanisms underlying the relationship between BPH and HU-033. Through not only cellular and nuclear receptor functional assays, but TP-mediated BPH rat model treated with HU-033, we demonstrated that HU-033 exerted antagonist effect on α1A- and α1D-adrenergic receptors in vitro and inhibitory effect on protein expression of androgen receptor and estrogen receptor alpha in vivo. Taken together, these results suggest that HU-033 is a novel candidate for the management of BPH.

14.
Int J Mol Sci ; 19(2)2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29462880

RESUMEN

Estrogen receptor-α positive (ERα⁺) breast cancers represent 75% of all invasive breast cancer cases, while de novo or acquired resistance to ER-directed therapy is also on the rise. Numerous factors contribute to this phenomenon including the recently-reported ESR1 gene mutations such as Y537S, which amplifies co-activator interactions with ERα and promotes constitutive activation of ERα function. Herein, we propose that direct targeting of the activation function-2 (AF2) site on ERα represents a promising alternative therapeutic strategy to overcome mutation-driven resistance in breast cancer. A systematic computer-guided drug discovery approach was employed to develop a potent ERα inhibitor that was extensively evaluated by a series of experiments to confirm its AF2-specific activity. We demonstrate that the developed small-molecule inhibitor effectively prevents ERα-coactivator interactions and exhibits a strong anti-proliferative effect against tamoxifen-resistant cells, as well as downregulates ERα-dependent genes and effectively diminishes the receptor binding to chromatin. Notably, the identified lead compound successfully inhibits known constitutively-active, resistance-associated mutant forms of ERα observed in clinical settings. Overall, this study reports the development of a novel class of ERα AF2 inhibitors, which have the potential to effectively inhibit ERα activity by a unique mechanism and to circumvent the issue of mutation-driven resistance in breast cancer.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Resistencia a Antineoplásicos/genética , Receptor alfa de Estrógeno/genética , Tiofenos/administración & dosificación , Sitios de Unión/efectos de los fármacos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Cromatina/genética , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Células MCF-7 , Mutación , Unión Proteica , Tamoxifeno/administración & dosificación , Tamoxifeno/efectos adversos
15.
Cell Rep ; 22(1): 163-174, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29298418

RESUMEN

Depolarization of neuroendocrine cells results in calcium influx, which induces vesicle exocytosis and alters gene expression. These processes, along with the restoration of resting membrane potential, are energy intensive. We hypothesized that cellular mechanisms exist to maximize energy production during excitation. Here, we demonstrate that NPAS4, an immediate early basic helix-loop-helix (bHLH)-PAS transcription factor, acts to maximize energy production by suppressing hypoxia-inducible factor 1α (HIF1α). As such, knockout of Npas4 from insulin-producing ß cells results in reduced OXPHOS, loss of insulin secretion, ß cell dedifferentiation, and type 2 diabetes. NPAS4 plays a similar role in the nutrient-sensing cells of the hypothalamus. Its knockout here results in increased food intake, reduced locomotor activity, and elevated peripheral glucose production. In conclusion, NPAS4 is critical for the coordination of metabolism during the stimulation of electrically excitable cells; its loss leads to the defects in cellular metabolism that underlie the cellular dysfunction that occurs in metabolic disease.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Hipotálamo/metabolismo , Células Neuroendocrinas/metabolismo , Fosforilación Oxidativa , Oxígeno/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Hipotálamo/citología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Ratones , Ratones Transgénicos , Células Neuroendocrinas/citología
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