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1.
Pharmacol Rev ; 75(6): 1140-1166, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37328294

RESUMO

Pharmacological agents used to treat or manage diseases can modify the level of heat strain experienced by chronically ill and elderly patients via different mechanistic pathways. Human thermoregulation is a crucial homeostatic process that maintains body temperature within a narrow range during heat stress through dry (i.e., increasing skin blood flow) and evaporative (i.e., sweating) heat loss, as well as active inhibition of thermogenesis, which is crucial to avoid overheating. Medications can independently and synergistically interact with aging and chronic disease to alter homeostatic responses to rising body temperature during heat stress. This review focuses on the physiologic changes, with specific emphasis on thermolytic processes, associated with medication use during heat stress. The review begins by providing readers with a background of the global chronic disease burden. Human thermoregulation and aging effects are then summarized to give an understanding of the unique physiologic changes faced by older adults. The effects of common chronic diseases on temperature regulation are outlined in the main sections. Physiologic impacts of common medications used to treat these diseases are reviewed in detail, with emphasis on the mechanisms by which these medications alter thermolysis during heat stress. The review concludes by providing perspectives on the need to understand the effects of medication use in hot environments, as well as a summary table of all clinical considerations and research needs of the medications included in this review. SIGNIFICANCE STATEMENT: Long-term medications modulate thermoregulatory function, resulting in excess physiological strain and predisposing patients to adverse health outcomes during prolonged exposures to extreme heat during rest and physical work (e.g., exercise). Understanding the medication-specific mechanisms of altered thermoregulation has importance in both clinical and research settings, paving the way for work toward refining current medication prescription recommendations and formulating mitigation strategies for adverse drug effects in the heat in chronically ill patients.


Assuntos
Aquecimento Global , Temperatura Alta , Humanos , Idoso , Regulação da Temperatura Corporal/fisiologia , Temperatura Corporal/fisiologia , Doença Crônica
2.
Arterioscler Thromb Vasc Biol ; 43(3): 427-442, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36700429

RESUMO

BACKGROUND: Considerable evidence links dietary salt intake with the development of hypertension, left ventricular hypertrophy, and increased risk of stroke and coronary heart disease. Despite extensive epidemiological and basic science interrogation of the relationship between high salt (HS) intake and blood pressure, it remains unclear how HS impacts endothelial cell (EC) and vascular structure in vivo. This study aims to elucidate HS-induced vascular pathology using a differential systemic decellularization in vivo approach. METHODS: We performed systematic molecular characterization of the endothelial glycocalyx and EC proteomes in mice with HS (8%) diet-induced hypertension versus healthy control animals. Isolation of eGC and EC compartments was achieved using differential systemic decellularization in vivo methodology. Altered protein expression in hypertensive compared to normal mice was characterized by liquid chromatography tandem mass spectrometry. Proteomic results were validated using functional assays, microscopic imaging, and histopathologic evaluation. RESULTS: Proteomic analysis revealed a significant downregulation of eGC and associated proteins in HS diet-induced hypertensive mice (among 1696 proteins identified in this group, 723 were markedly decreased in abundance, while only 168 were increased in abundance. Bioinformatic analysis indicated substantial derangement of the eGC layer, which was subsequently confirmed by fluorescent and electron microscopy assessment of vessel damage ex vivo. In the EC fraction, HS-induced hypertension significantly altered protein mediators of contractility, metabolism, mechanotransduction, renal function, and the coagulation cascade. In particular, we observed dysregulation of integrin subunits α2, α2b, and α5, which was associated with arterial wall inflammation and substantial infiltration of CD68+ monocyte-macrophages. Consequently, HS-induced hypertensive mice also displayed reduced vascular integrity of multiple organs including lungs, kidneys, and heart. CONCLUSIONS: These findings provide novel molecular insight into HS-induced structural changes in eGC and EC composition that may increase cardiovascular risk and potentially guide the development of new diagnostics and therapeutic interventions.


Assuntos
Hipertensão , Cloreto de Sódio na Dieta , Camundongos , Animais , Cloreto de Sódio na Dieta/efeitos adversos , Proteômica , Mecanotransdução Celular , Pressão Sanguínea/fisiologia
3.
Acta Biotheor ; 72(3): 10, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39207534

RESUMO

In clinical endocrinology, it is often assumed that the results of thyroid hormone function tests (TFTs) before total thyroidectomy are considered euthyroid when the circulating concentrations of thyrotropin [TSH] and free thyroxine [FT4] are within the normal reference ranges. Postoperative thyroid replacement therapy with levothyroxine. The aim of L-T4 is to reproduce the preoperative euthyroid condition. Currently, intra-individual changes in the euthyroid set point before and after total thyroidectomy are only partly understood. After total thyroidectomy, a greater postoperative [FT4] than preoperative [FT4] for equivalent euthyroid [TSH] was found, with differences ranging from 3 to 8 pmol/L. This unexplained difference can be explained by the use of a mathematical model of the hypothalamus-pituitary-thyroid (HPT) axis set point theory. In this article, the postoperative HPT euthyroid set point was calculated using a dataset of total thyroidectomized patients with at least three distinguishable postoperative TFTs. The postoperative [TSH] set point was used as a homeostatic reference for the comparison of preoperative TFTs. The preoperative [FT4] value was equal to the postoperative [FT4] value in 50% of the patients, divided by a factor of ~ 1.25 (within +/- 10%). The factor of 1.25 stems from the lack of postoperative use of thyroidal triiodothyronine (T3). Furthermore, approximately 25% of the patients presented a greater preoperative [FT4] difference than postoperative [FT4]/1.25 combined with a normal [TSH] difference. Based on these observations, the effect of T3 on the value of the [FT4] set point was analyzed and explained from a control theory perspective.


Assuntos
Glândula Tireoide , Tireoidectomia , Tiroxina , Tri-Iodotironina , Humanos , Tiroxina/sangue , Tri-Iodotironina/sangue , Glândula Tireoide/cirurgia , Glândula Tireoide/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Tireotropina/sangue , Sistema Hipotálamo-Hipofisário/metabolismo , Testes de Função Tireóidea/métodos , Adulto , Hipófise/metabolismo , Hipófise/cirurgia , Idoso , Hipotálamo/metabolismo
4.
Am J Physiol Endocrinol Metab ; 320(1): E139-E150, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33236920

RESUMO

The current COVID-19 pandemic is probably the worst the world has ever faced since the start of the new millennium. Although the respiratory system is the most prominent target of SARS-CoV-2 (the contagion of COVID-19), extrapulmonary involvement are emerging as important contributors of its morbidity and lethality. This article summarizes the impact of SARS-CoV and SARS-CoV-2 on the endocrine system to facilitate our understanding of the nature of coronavirus-associated endocrinopathy. Although new data are rapidly accumulating on this novel infection, many of the endocrine manifestations of COVID-19 remain incompletely elucidated. We, hereby, summarize various endocrine dysfunctions including coronavirus-induced new onset diabetes mellitus, hypocortisolism, thyroid hormone, and reproductive system aberrations so that clinicians armed with such insights can potentially benefit patients with COVID-19 at the bedside.


Assuntos
COVID-19/complicações , Doenças do Sistema Endócrino/virologia , Enzima de Conversão de Angiotensina 2 , Humanos , Neuropilina-1 , Pandemias , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , SARS-CoV-2 , Serina Endopeptidases , Síndrome Respiratória Aguda Grave
5.
Small ; 16(31): e2002872, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32603020

RESUMO

Obesity is a serious epidemic health problem that can cause many other diseases including type 2 diabetes and cardiovascular diseases. Current approaches to combat obesity suffer from low effectiveness and adverse side effects. Here, a new self-administrable and minimally invasive transdermal drug delivery strategy for home-based long-term treatment of obesity and other diseases is developed. Specifically, ultrathin, core-shelled, and lance-shaped polymeric drug reservoirs (micro-lances [MLs]) are readily fabricated by a thermal pressing molding method and totally implanted into subcutaneous fat by lancing through the skin. Using a diet-induced obese mouse model, it is shown that the development of obesity and associated metabolic disorders is effectively inhibited by applying therapeutic core-shelled MLs once every 2 weeks. The outstanding therapeutic effects are attributable to highly localized and biphasic drug release, as well as combination therapy based on browning transformation of white fat and enhanced insulin sensitivity.


Assuntos
Diabetes Mellitus Tipo 2 , Preparações Farmacêuticas , Animais , Camundongos , Obesidade , Gordura Subcutânea
6.
Magn Reson Med ; 84(1): 384-395, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31799761

RESUMO

PURPOSE: The vascular blood flow in brown adipose tissue (BAT) is important for handling triglyceride clearance, increased blood flow and oxygenation. We used dynamic contrast-enhanced (DCE)-MRI and fat fraction (FF) imaging for investigating vascular perfusion kinetics in brown and beige adipose tissues with cold exposure or treatment with ß3-adrenergic agonist. METHODS: FF imaging and DCE-MRI using gadolinium-diethylenetriaminepentaacetic acid were performed in interscapular BAT (iBAT) and beige tissues using male Wister rats (n = 38). Imaging was performed at thermoneutral condition and with either cold exposure, treatment with pharmacological agent CL-316,243, or saline. DCE-MRI and FF data were co-registered to enhance the understanding of metabolic activity. RESULTS: Uptake of contrast agent in activated iBAT and beige tissues were significantly (P < .05) higher than nonactivated iBAT. The Ktrans and kep increased significantly in iBAT and beige tissues after treatment with either cold exposure or ß3-adrenergic agonist. The FF decreased in activated iBAT and beige tissues. The Ktrans and FF from iBAT and beige tissues were inversely correlated (r = 0.97; r = 0.94). Significant increase in vascular endothelial growth factor expression and Ktrans in activated iBAT and beige tissues were in agreement with the increased vasculature and vascular perfusion kinetics. The iBAT and beige tissues were validated by measuring molecular markers. CONCLUSION: Increased Ktrans and decreased FF in iBAT and beige tissues were in agreement with the vascular perfusion kinetics facilitating the clearance of free fatty acids. The methodology can be extended for the screening of browning agents.


Assuntos
Tecido Adiposo Bege , Tecido Adiposo Branco , Tecido Adiposo Marrom/diagnóstico por imagem , Animais , Imageamento por Ressonância Magnética , Masculino , Ratos , Fator A de Crescimento do Endotélio Vascular
7.
Int J Mol Sci ; 21(5)2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32143325

RESUMO

Daily activities expose muscles to innumerable impacts, causing accumulated tissue damage and inflammation that impairs muscle recovery and function, yet the mechanism modulating the inflammatory response in muscles remains unclear. Our study suggests that Forkhead box A2 (FoxA2), a pioneer transcription factor, has a predominant role in the inflammatory response during skeletal muscle injury. FoxA2 expression in skeletal muscle is upregulated by fatty acids and peroxisome proliferator-activated receptors (PPARs) but is refractory to insulin and glucocorticoids. Using PPARß/δ agonist GW501516 upregulates FoxA2, which in turn, attenuates the production of proinflammatory cytokines and reduces the infiltration of CD45+ immune cells in two mouse models of muscle inflammation, systemic LPS and intramuscular injection of carrageenan, which mimic localized exercise-induced inflammation. This reduced local inflammatory response limits tissue damage and restores muscle tetanic contraction. In line with these results, a deficiency in either PPARß/δ or FoxA2 diminishes the action of the PPARß/δ agonist GW501516 to suppress an aggravated inflammatory response. Our study suggests that FoxA2 in skeletal muscle helps maintain homeostasis, acting as a gatekeeper to maintain key inflammation parameters at the desired level upon injury. Therefore, it is conceivable that certain myositis disorders or other forms of painful musculoskeletal diseases may benefit from approaches that increase FoxA2 activity in skeletal muscle.


Assuntos
Fator 3-beta Nuclear de Hepatócito/metabolismo , Músculo Esquelético/metabolismo , Mioblastos/metabolismo , PPAR delta/agonistas , PPAR beta/agonistas , Animais , Citocinas/metabolismo , Regulação da Expressão Gênica , Glucocorticoides/metabolismo , Células HEK293 , Homeostase , Humanos , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Tiazóis/farmacologia , Ativação Transcricional , Regulação para Cima
8.
Biochem Biophys Res Commun ; 516(1): 144-148, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31200959

RESUMO

Abnormal adhesion of red blood cells (RBC) to the endothelium has been linked to the pathophysiology of several diseases associated with vascular disorders. Various biochemical changes on the outer membrane of RBC, as well as plasma protein levels, have been identified as possibly playing key roles, but the detailed interplay between plasma factors and cellular factors often remains unclear. In this work, we identified an alternative pathway by demonstrating that non-adsorbing macromolecules can also have a marked impact on the adhesion efficiency of RBC from patients with type 2 Diabetes (T2DM) to endothelial cells (EC). RBC isolated from blood samples of T2DM patients were suspended in isotonic solutions of dextran in order to mimic the impact of non-adsorbing macromolecules. Static and continuous flow adhesion assays were used to determine the adhesion behavior of T2DM RBC with EC and the results compared with those of normal controls. We found that the presence of non-adsorbing molecules promotes an increase in T2DM RBC - EC adhesion and that these RBC exhibit much greater adhesion than normal red cells. Our results thus suggest that the depletion mechanism might be an alternative phenomenon through which plasma proteins could cause enhanced RBC-EC adhesion in diabetes mellitus. These findings contribute towards the comprehensive understanding of pathophysiological mechanisms of vascular complications in diabetes and other diseases with similar vascular sequelae.


Assuntos
Diabetes Mellitus Tipo 2/patologia , Células Endoteliais/patologia , Eritrócitos/patologia , Adulto , Adesão Celular , Comunicação Celular , Células Endoteliais/citologia , Eritrócitos/citologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Pessoa de Meia-Idade
9.
Eur J Nutr ; 58(1): 301-313, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29236165

RESUMO

PURPOSE: To investigate acute effects of two doses of a polyphenol-rich curry made with seven different spices and four base vegetables, eaten with white rice, on 24 h glucose response, postprandial insulinemia, triglyceridemia and 24 h urinary total polyphenol excretion (TPE). METHODS: Randomized, controlled, dose-response crossover trial in healthy, Chinese men [n = 20, mean ± standard deviation (SD) age 23.7 ± 2.30 years, BMI 23.0 ± 2.31 kg/m2] who consumed test meals matched for calories, macronutrients and total vegetables content, consisting either Dose 0 Control (D0C) or Dose 1 Curry (D1C) or Dose 2 Curry (D2C) meal. 24 h glucose concentration was measured using continuous glucose monitoring (CGM), together with postprandial plasma insulin and triglyceride for up to 7 h. Total polyphenol content (TPC) of test meals and urinary TPE were measured using the Folin-Ciocalteu assay. RESULTS: TPC for D0C, D1C and D2C were 130 ± 18, 556 ± 19.7 and 1113 ± 211.6 mg gallic acid equivalent (GAE) per portion served, respectively (p < 0.0001). Compared with D0C meal, we found significant linear dose-response reductions in the 3-h postprandial incremental AUC (iAUC) for CGM glucose of 19% and 32% during D1C and D2C meals respectively (p < 0.05) and non-significant linear dose response reductions in iAUC of insulin (p = 0.089). Notably, we found significant dose-dependent increases in postprandial triglyceride with increasing curry doses (p < 0.01). Significant increases in TPE with increasing curry doses were also observed (p < 0.01). CONCLUSION: Polyphenol-rich curry intake can improve postprandial glucose homeostasis. The longer term effects remain to be established.


Assuntos
Glicemia/metabolismo , Homeostase/efeitos dos fármacos , Polifenóis/farmacologia , Especiarias/estatística & dados numéricos , Verduras/metabolismo , Adulto , Glicemia/efeitos dos fármacos , China , Estudos Cross-Over , Relação Dose-Resposta a Droga , Humanos , Insulina/urina , Masculino , Polifenóis/metabolismo , Período Pós-Prandial , Triglicerídeos/sangue , Adulto Jovem
11.
J Theor Biol ; 419: 333-342, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28039012

RESUMO

Glucose plasma measurements for diabetes patients are generally presented as a glucose concentration-time profile with 15-60min time scale intervals. This limited resolution obscures detailed dynamic events of glucose appearance and metabolism. Measurement intervals of 15min or more could contribute to imperfections in present diabetes treatment. High resolution data from mixed meal tolerance tests (MMTT) for 24 type 1 and type 2 diabetes patients were used in our present modeling. We introduce a model based on the physiological properties of transport, storage and utilization. This logistic approach follows the principles of electrical network analysis and signal processing theory. The method mimics the physiological equivalent of the glucose homeostasis comprising the meal ingestion, absorption via the gastrointestinal tract (GIT) to the endocrine nexus between the liver, pancreatic alpha and beta cells. This model demystifies the metabolic 'black box' by enabling in silico simulations and fitting of individual responses to clinical data. Five-minute intervals MMTT data measured from diabetic subjects result in two independent model parameters that characterize the complete glucose system response at a personalized level. From the individual data measurements, we obtain a model which can be analyzed with a standard electrical network simulator for diagnostics and treatment optimization. The insulin dosing time scale can be accurately adjusted to match the individual requirements of characterized diabetic patients without the physical burden of treatment.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Insulina/administração & dosagem , Modelos Biológicos , Medicina de Precisão/métodos , Algoritmos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucose/metabolismo , Homeostase , Humanos , Hipoglicemiantes/administração & dosagem
12.
Eur J Nutr ; 56(1): 77-87, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26439722

RESUMO

PURPOSE: Milk protein ingestion reduces post-meal glycemia when consumed either before or together with carbohydrate foods. The aim of this study was to compare the effects of dairy and soy milk consumed either before (preload) or together with (co-ingestion) a carbohydrate (bread), on postprandial blood glucose, insulin and gastric emptying in healthy participants. METHODS: Twelve healthy Chinese male participants were studied on five separate occasions using a randomized crossover design. White wheat bread consumed with water was used as a reference meal. Capillary and venous bloods were sampled pretest and 3.5 h post-test meal for glucose and insulin measurement. Gastric emptying was measured using real-time ultrasonography. RESULTS: Co-ingestion of dairy milk or soy milk with bread lowered postprandial blood glucose response and glycemic index. Co-ingesting soy milk with bread increased insulin response and insulinemic index significantly compared to co-ingestion of dairy milk and preload treatments. Preloads (30 min prior to bread) significantly lowered postprandial glycemia and insulinemia compared to co-ingestion. Gastric emptying was slower after co-ingesting dairy milk with bread than after reference meal. CONCLUSIONS: Preloading either soy milk or dairy milk results in greater reduction in glycemic response compared to co-ingestion alone. This dietary practice may have therapeutic advantage in communities consuming high GI diets. Optimal glucose control may have the potential for increasing the time of transition from prediabetes to type 2 diabetes in Asian communities. CLINICAL TRIAL REGISTRATION: This trial was registered at clinicaltrials.gov as NCT 02151188.


Assuntos
Glicemia/metabolismo , Esvaziamento Gástrico , Insulina/sangue , Leite/química , Período Pós-Prandial , Leite de Soja/administração & dosagem , Adulto , Animais , Povo Asiático , Pão , Estudos Cross-Over , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/prevenção & controle , Dieta , Carboidratos da Dieta/administração & dosagem , Humanos , Masculino , Refeições , Estado Pré-Diabético/sangue , Estado Pré-Diabético/dietoterapia , Resultado do Tratamento , Adulto Jovem
13.
Int J Med Sci ; 14(7): 639-647, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28824295

RESUMO

Background: Modern medicine recognizes that salient, inherent variations between Caucasians and Asians exist. Radical changes are occurring in the health scene with increasing emphasis centered on the recognition of inter-individual variations unique to Asians that impact on medical management and outcomes. Aim: This review analyzes distinct features or outcomes in terms of epidemiology, disease thresholds, diagnostic cutoffs and treatment responses of Asian people compared with non-Asians. Methods: This review is based on a literature search via PubMed and MEDLINE for relevant articles related to the Asian phenotype and its impact on health and disease. Results: An 'Asian phenotype' could be characterized across the spectrum of biomedical disciplines and underscores the major challenges clinicians must face in their daily management of a cosmopolitan population and their extrapolation of research outcomes. Conclusion: Interventions for various ailments that have traditionally ignored population differences have now entered the age of personalized, stratified or precision medicine requiring an individualized approach being adopted as a new standard of care. Factoring in Asian phenotypes is essential for the medical research community and the development of improved clinical practice guidelines across a continuum of disciplines that will ultimately translate to better human health round the world.


Assuntos
Povo Asiático/genética , Epidemiologia Molecular , População Branca/genética , Humanos , Fenótipo , Medicina de Precisão
15.
J Biol Syst ; 25(1): 119-143, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28989211

RESUMO

The effects of a single oral dose of liothyronine (L-T3) on thyroid stimulating hormone (TSH) and other related thyroid system parameters are partly understood despite therapeutic use of this hormone over many decades. We characterize individualized responses of the hypothalamus-pituitary-thyroid (HPT) axis and its related temporal hormonal profile using an electrical network model. Based on thyroid hormone responses from blood samples using a single 50 µg oral dose of liothyronine in healthy persons with a normal operating euthyroid feedback HPT system, we derived an equivalent electrical circuit model for the system's responses. The mathematical model was tested with a circuit simulator and validated with individualized clinical data. This signal processing technique makes the evaluation of bioequivalence and bioavailability of various preparations of liothyronine at an individualized level a feasible endeavor for clinical application.

16.
J Biol Chem ; 290(23): 14679-91, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-25931124

RESUMO

Brown adipose tissue expends energy in the form of heat via the mitochondrial uncoupling protein UCP1. Recent studies showed that brown adipose tissue is present in adult humans and may be exploited for its anti-obesity and anti-diabetes actions. Apelin is an adipocyte-derived hormone that plays important roles in energy metabolism. Here, we report that apelin-APJ signaling promotes brown adipocyte differentiation by increasing the expressions of brown adipogenic and thermogenic transcriptional factors via the PI3K/Akt and AMPK signaling pathways. It is also found that apelin relieves the TNFα inhibition on brown adipogenesis. In addition, apelin increases the basal activity of brown adipocytes, as evidenced by the increased PGC1α and UCP1 expressions, mitochondrial biogenesis, and oxygen consumption. Finally, we provide both in vitro and in vivo evidence that apelin is able to increase the brown-like characteristics in white adipocytes. This study, for the first time, reveals the brown adipogenic and browning effects of apelin and suggests a potential therapeutic route to combat obesity and related metabolic disorders.


Assuntos
Adipócitos Marrons/citologia , Adipócitos Brancos/citologia , Adipogenia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Adipócitos Marrons/metabolismo , Adipócitos Brancos/metabolismo , Adipocinas , Animais , Apelina , Receptores de Apelina , Linhagem Celular , Células Cultivadas , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/análise , Canais Iônicos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/metabolismo , Ratos , Receptores Acoplados a Proteínas G/análise , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Proteína Desacopladora 1
17.
Br J Nutr ; 115(12): 2130-7, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27185412

RESUMO

The short-term effect of soya protein, polydextrose and their combination on energy intake (EI) was investigated in Chinese. In total, twenty-seven healthy, normotensive and lean Chinese men aged 21-40 years were given four different soyabean curd preloads with or without polydextrose. The study was a repeated-measure, randomised, cross-over design. The consumption of high-protein soyabean curd alone or in addition with polydextrose as a preload led to greater reduction in EI at a subsequent meal. A similar observation was also found after intake of low-protein soyabean curd with polydextrose. The gut hormone responses mirrored the reduction in food intake. It appears that incorporation of polydextrose either with low- or high-protein soyabean curd could be a potential strategy to reduce EI and assist with weight management. The popular consumption of soyabean curd in Chinese makes it an ideal vehicle for incorporation of polydextrose. This evidence-based dietary approach can serve as a guideline for developing functional foods for weight reduction and weight maintenance.


Assuntos
Glicemia/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Energia/efeitos dos fármacos , Esvaziamento Gástrico/efeitos dos fármacos , Hormônios Gastrointestinais/metabolismo , Glucanos/farmacologia , Proteínas de Soja/farmacologia , Adulto , Apetite/efeitos dos fármacos , China , Estudos Cross-Over , Carboidratos da Dieta/farmacologia , Proteínas Alimentares/farmacologia , Alimento Funcional , Grelina/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Índice Glicêmico , Humanos , Masculino , Refeições , Obesidade/dietoterapia , Obesidade/metabolismo , Redução de Peso , Adulto Jovem
18.
Nutr J ; 15: 27, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26979583

RESUMO

BACKGROUND: Cardio-Metabolic Disease (CMD) is the leading cause of death globally and particularly in Asia. Postprandial elevation of glycaemia, insulinaemia, triglyceridaemia are associated with an increased risk of CMD. While studies have shown that higher protein intake or increased meal frequency may benefit postprandial metabolism, their combined effect has rarely been investigated using composite mixed meals. We therefore examined the combined effects of increasing meal frequency (2-large vs 6-smaller meals), with high or low-protein (40 % vs 10 % energy from protein respectively) isocaloric mixed meals on a range of postprandial CMD risk markers. METHODS: In a randomized crossover study, 10 healthy Chinese males (Age: 29 ± 7 years; BMI: 21.9 ± 1.7 kg/m(2)) underwent 4 dietary treatments: CON-2 (2 large Low-Protein meals), CON-6 (6 Small Low-Protein meals), PRO-2 (2 Large High-Protein meals) and PRO-6 (6 Small High-Protein meals). Subjects wore a continuous glucose monitor (CGM) and venous blood samples were obtained at baseline and at regular intervals for 8.5 h to monitor postprandial changes in glucose, insulin, triglycerides and high sensitivity C-reactive protein (hsCRP). Blood pressure was measured at regular intervals pre- and post- meal consumption. Urine was collected to measure excretion of creatinine and F2-isoprostanes and its metabolites over the 8.5 h postprandial period. RESULTS: The high-protein meals, irrespective of meal frequency were beneficial for glycaemic health since glucose incremental area under the curve (iAUC) for PRO-2 (185 ± 166 mmol.min.L(-1)) and PRO-6 (214 ± 188 mmol.min.L(-1)) were 66 and 60 % lower respectively (both p < 0.05), compared with CON-2 (536 ± 290 mmol.min.L(-1)). The iAUC for insulin was the lowest for PRO-6 (13.7 ± 7.1 U.min.L(-1)) as compared with CON-2 (28.4 ± 15.6 U.min.L(-)1), p < 0.001. There were no significant differences in postprandial responses in other measurements between the dietary treatments. CONCLUSIONS: The consumption of composite meals with higher protein content, irrespective of meal frequency appears to be beneficial for postprandial glycemic and insulinemic responses in young, healthy Chinese males. Implications of this study may be useful in the Asian context where the consumption of high glycemic index, carbohydrate meals is prevalent. TRIAL REGISTRATION: NCT02529228 .


Assuntos
Doenças Cardiovasculares/sangue , Dieta com Restrição de Proteínas , Proteínas Alimentares/administração & dosagem , Síndrome Metabólica/sangue , Período Pós-Prandial/fisiologia , Adulto , Povo Asiático , Glicemia/metabolismo , Pressão Sanguínea , Índice de Massa Corporal , Proteína C-Reativa/metabolismo , Creatinina/urina , Estudos Cross-Over , Dieta , Ingestão de Energia , F2-Isoprostanos/urina , Índice Glicêmico , Humanos , Insulina/sangue , Masculino , Refeições , Fatores de Risco , Triglicerídeos/sangue , Adulto Jovem
19.
MAGMA ; 29(2): 277-86, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26747282

RESUMO

OBJECTIVE: The aim was to auto-segment and characterize brown adipose, white adipose and muscle tissues in rats by multi-parametric magnetic resonance imaging with validation by histology and UCP1. MATERIALS AND METHODS: Male Wistar rats were randomized into two groups for thermoneutral (n = 8) and cold exposure (n = 8) interventions, and quantitative MRI was performed longitudinally at 7 and 11 weeks. Prior to imaging, rats were maintained at either thermoneutral body temperature (36 ± 0.5 °C), or short term cold exposure (26 ± 0.5 °C). Neural network based automatic segmentation was performed on multi-parametric images including fat fraction, T2 and T2* maps. Isolated tissues were subjected to histology and UCP1 analysis. RESULTS: Multi-parametric approach showed precise delineation of the interscapular brown adipose tissue (iBAT), white adipose tissue (WAT) and muscle regions. Neural network based segmentation results were compared with manually drawn regions of interest, and showed 96.6 and 97.1% accuracy for WAT and BAT respectively. Longitudinal assessment of the iBAT volumes showed a reduction at 11 weeks of age compared to 7 weeks. The cold exposed group showed increased iBAT volume compared to thermoneutral group at both 7 and 11 weeks. Histology and UCP1 expression analysis supported our imaging results. CONCLUSION: Multi-parametric MR based neural network auto-segmentation provides accurate separation of BAT, WAT and muscle tissues in the interscapular region. The cold exposure improves the classification and quantification of heterogeneous BAT.


Assuntos
Tecido Adiposo Marrom/diagnóstico por imagem , Temperatura Baixa , Interpretação de Imagem Assistida por Computador/métodos , Imagem Multimodal/métodos , Escápula/diagnóstico por imagem , Articulação do Ombro/diagnóstico por imagem , Tecido Adiposo Marrom/anatomia & histologia , Animais , Masculino , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Escápula/anatomia & histologia , Sensibilidade e Especificidade , Articulação do Ombro/anatomia & histologia
20.
Appetite ; 101: 119-24, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26946279

RESUMO

OBJECTIVES: Previous studies reveal that the Three-Factor Eating Questionnaire (TFEQ), which assesses eating behaviour, performs differently across population groups and cultures. We aimed to identify the factor structure that is most appropriate to capture eating behaviour in an overweight and obese Chinese population in Singapore. METHODS: TFEQ-51 was administered to 444 Chinese subjects pooled from four separate studies and scored according to various alternative versions of the TFEQ. Confirmatory factor analyses and goodness of fit indices were used to determine the most appropriate factor structure. Known-group validity analyses were conducted. RESULTS: Niemeier's Disinhibition Factors and the TFEQ-R18 factor structures were found to be the most applicable in our population based on goodness of fit indices, with a x(2)/df ratio of <3, RMSEA of ≤ 0.6 and a CFI value of >0.9 for both. Only two of three factors (Emotional Eating and Uncontrolled Eating) of the TFEQ-R18 showed good internal consistency, while none of Niemeier's Disinhibition Factors showed good internal consistency. Known-group validity showed that Emotional Eating and Internal Disinhibition were significantly associated with higher BMI. CONCLUSION: We found that the TFEQ-R18 factor structure is the most appropriate and practical for use in measuring eating behaviour in an overweight and obese Chinese population in Singapore.


Assuntos
Ingestão de Alimentos/psicologia , Obesidade/psicologia , Sobrepeso/psicologia , Psicometria/métodos , Inquéritos e Questionários , Adulto , Povo Asiático , Índice de Massa Corporal , Estudos Transversais , Emoções , Feminino , Humanos , Masculino , Singapura
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