Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 282
Filtrar
Mais filtros

Medicinas Complementares
Tipo de documento
Intervalo de ano de publicação
1.
J Biol Chem ; 300(1): 105563, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38101568

RESUMO

Intermediary metabolites and flux through various pathways have emerged as key determinants of post-translational modifications. Independently, dynamic fluctuations in their concentrations are known to drive cellular energetics in a bi-directional manner. Notably, intracellular fatty acid pools that drastically change during fed and fasted states act as precursors for both ATP production and fatty acylation of proteins. Protein fatty acylation is well regarded for its role in regulating structure and functions of diverse proteins; however, the effect of intracellular concentrations of fatty acids on protein modification is less understood. In this regard, we unequivocally demonstrate that metabolic contexts, viz. fed and fasted states, dictate the extent of global fatty acylation. Moreover, we show that presence or absence of glucose that influences cellular and mitochondrial uptake/utilization of fatty acids and affects palmitoylation and oleoylation, which is consistent with their intracellular abundance in fed and fasted states. Employing complementary approaches including click-chemistry, lipidomics, and imaging, we show the top-down control of cellular metabolic state. Importantly, our results establish the crucial role of mitochondria and retrograde signaling components like SIRT4, AMPK, and mTOR in orchestrating protein fatty acylation at a whole cell level. Specifically, pharmacogenetic perturbations that alter either mitochondrial functions and/or retrograde signaling affect protein fatty acylation. Besides illustrating the cross-talk between carbohydrate and lipid metabolism in mediating bulk post-translational modification, our findings also highlight the involvement of mitochondrial energetics.


Assuntos
Acilação , Ácidos Graxos , Metabolismo dos Lipídeos , Processamento de Proteína Pós-Traducional , Proteínas , Trifosfato de Adenosina/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Química Click , Jejum/fisiologia , Ácidos Graxos/metabolismo , Glucose/metabolismo , Lipidômica , Lipoilação , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas/química , Proteínas/metabolismo , Sirtuínas/metabolismo , Serina-Treonina Quinases TOR/metabolismo
2.
Nutrients ; 15(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36904225

RESUMO

INTRODUCTION: Christian Orthodox fasting is a pattern high in complex carbohydrates and low in refined carbohydrates. It has been explored in association with its potential health benefits. The present review aims to comprehensively explore the existing available clinical data concerning the potential favorable impact of the dietary pattern of Christian Orthodox fasting on human health. METHODS: PubMed database, Web of Science and Google Scholar were extensively searched in order to identify the more appropriate clinical studies that explore the effect of Christian Orthodox fasting on health-related outcomes in humans utilizing relative keywords. We initially retrieved 121 records through database searching. After applying several exclusion criteria, 17 clinical studies were finally included in this review study. DISCUSSION: Christian Orthodox fasting showed beneficial effects concerning glucose and lipid control, whereas the data for blood pressure remain inconclusive. Concerning weight control, fasters were characterized by lower body mass and lower caloric intake in the course of the fasting periods. During fasting, this pattern is higher in fruits and vegetables, showing the absence of dietary deficiencies for iron and folate. Nevertheless, dietary deficiencies were recorded for calcium and vitamin B2, and also hypovitaminosis D has been noticed in monks. Interestingly, the vast majority of monks do present with both good quality of life and mental health. CONCLUSIONS: Overall, Christian Orthodox fasting is a dietary pattern low in refined carbohydrates and high in complex carbohydrates and fiber that may be beneficial for human health promotion and chronic disease prevention. However, further studies are strongly recommended on the impact of long-term religious fasting on HDL cholesterol levels and blood pressure.


Assuntos
Dieta com Restrição de Carboidratos , Jejum , Humanos , Carboidratos , Cristianismo , Dieta , Jejum/fisiologia , Qualidade de Vida , Fatores de Risco Cardiometabólico , Saúde Mental
3.
Int J Mol Sci ; 24(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36834616

RESUMO

Molecular profiling of the hypothalamus in response to metabolic shifts is a critical cue to better understand the principle of the central control of whole-body energy metabolism. The transcriptional responses of the rodent hypothalamus to short-term calorie restriction have been documented. However, studies on the identification of hypothalamic secretory factors that potentially contribute to the control of appetite are lacking. In this study, we analyzed the differential expression of hypothalamic genes and compared the selected secretory factors from the fasted mice with those of fed control mice using bulk RNA-sequencing. We verified seven secretory genes that were significantly altered in the hypothalamus of fasted mice. In addition, we determined the response of secretory genes in cultured hypothalamic cells to treatment with ghrelin and leptin. The current study provides further insights into the neuronal response to food restriction at the molecular level and may be useful for understanding the hypothalamic control of appetite.


Assuntos
Hipotálamo , Inanição , Camundongos , Animais , Hipotálamo/metabolismo , Leptina/metabolismo , Inanição/metabolismo , Apetite/fisiologia , Jejum/fisiologia , Grelina/metabolismo , Perfilação da Expressão Gênica
4.
Am J Physiol Endocrinol Metab ; 321(6): E802-E820, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34747202

RESUMO

Sprint interval training (SIT) is a time-efficient alternative to endurance exercise, conferring beneficial skeletal muscle metabolic adaptations. Current literature has investigated the nutritional regulation of acute and chronic exercise-induced metabolic adaptations in muscle following endurance exercise, principally comparing the impact of training in fasted and carbohydrate-fed (CHO) conditions. Alternative strategies such as exercising in low CHO, protein-fed conditions remain poorly characterized, specifically pertaining to adaptations associated with SIT. Thus, this study aimed to compare the metabolic and performance adaptations to acute and short-term SIT in the fasted state with preexercise hydrolyzed (WPH) or concentrated (WPC) whey protein supplementation. In healthy males, preexercise protein ingestion did not alter exercise-induced increases in PGC-1α, PDK4, SIRT1, and PPAR-δ mRNA expression following acute SIT. However, supplementation of WPH beneficially altered acute exercise-induced CD36 mRNA expression. Preexercise protein ingestion attenuated acute exercise-induced increases in muscle pan-acetylation and PARP1 protein content compared with fasted SIT. Acute serum metabolomic differences confirmed greater preexercise amino acid delivery in protein-fed compared with fasted conditions. Following 3 wk of SIT, training-induced increases in mitochondrial enzymatic activity and exercise performance were similar across nutritional groups. Interestingly, resting muscle acetylation status was downregulated in WPH conditions following training. Such findings suggest preexercise WPC and WPH ingestion positively influences metabolic adaptations to SIT compared with fasted training, resulting in either similar or enhanced performance adaptations. Future studies investigating nutritional modulation of metabolic adaptations to exercise are warranted to build upon these novel findings.NEW & NOTEWORTHY These are the first data to show the influence of preexercise protein on serum and skeletal muscle metabolic adaptations to acute and short-term sprint interval training (SIT). Preexercise whey protein concentrate (WPC) or hydrolysate (WPH) feeding acutely affected the serum metabolome, which differentially influenced acute and chronic changes in mitochondrial gene expression, intracellular signaling (acetylation and PARylation) resulting in either similar or enhanced performance outcomes when compared with fasted training.


Assuntos
Adaptação Fisiológica , Jejum/fisiologia , Treinamento Intervalado de Alta Intensidade , Resistência Física , Proteínas do Soro do Leite/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Adolescente , Adulto , Análise Química do Sangue , Suplementos Nutricionais , Método Duplo-Cego , Treinamento Intervalado de Alta Intensidade/métodos , Humanos , Masculino , Metaboloma/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Resistência Física/efeitos dos fármacos , Resistência Física/genética , Corrida , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transcriptoma/efeitos dos fármacos , Proteínas do Soro do Leite/administração & dosagem , Adulto Jovem
5.
Neuropeptides ; 88: 102165, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34126542

RESUMO

Adropin has been shown to be involved in the regulation of food intake in mice. However, the mechanism of adropin in feeding regulation is still largely unknown. Using the tilapia, Oreochromis niloticus, we identified and characterized a novel form of adropin (designated adropin-b) encoding a 68-amino acid precursor. Although adropin-b shared low amino acid identities with its tilapia paralog (designated adropin-a), synteny analysis proved that tilapia adropin is orthologous to its human counterpart. The transcripts of adropin-b were ubiquitously expressed in various tissues with the highest levels in the olfactory bulb. A decrease in adropin-b mRNA levels was observed 1 h following a meal in the olfactory bulb, hypothalamus, and optic tectum, whereas fasting for 7 days induced an increase in adropin-b mRNA levels in the olfactory bulb, hypothalamus, and optic tectum of tilapia brain. However, no changes in adropin-a mRNA levels were observed in the postprandial and fasting state. Intraperitoneal injection of tilapia adropin-b was shown to increase food consumption, but adropin-a did not affect feeding. Co-treatment of the fish with adropin-b and neuropeptide Y (NPY) had no additive effects on appetite. The appetite stimulatory effects of adropin-b appeared to be mediated by upregulating the orexigenic Npy, Orexin, and Proapelin gene expression, paralleled by inhibition of the mRNA levels of anorexigenic proopiomelanocortin (Pomc) and cocaine-amphetamine-regulated transcript (Cart) in vivo and in vitro. These observations suggested that adropin-b participated in appetite control and gene regulation of central orexigenic and anorexigenic factors in a fish model.


Assuntos
Clonagem Molecular , Ingestão de Alimentos/fisiologia , Regulação da Expressão Gênica/fisiologia , Hipotálamo/metabolismo , Neuropeptídeo Y/metabolismo , Animais , Regulação do Apetite/fisiologia , Ciclídeos/genética , Ciclídeos/metabolismo , Jejum/fisiologia , Expressão Gênica/fisiologia , Tilápia/genética , Tilápia/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-33785435

RESUMO

Cholecystokinin (CCK) and peptide YY (PYY) have been investigated as gut hormones that send satiation signals to the brain in mammals. There is evidence that chicken PYY mRNA expression was the highest in the pancreas compared to other tissues. We recently suggested that insulin-like growth factor (IGF)-1 and its binding proteins (IGFBPs) may be involved in the appetite regulation system in chicks. In the present study, in order to evaluate the possible roles of CCK, PYY, and IGF-related proteins in the appetite regulation system in chicks, we analyzed changes in the mRNA levels of these genes in response to fasting and re-feeding in layer and hyperphagic broiler chicks. In layer chicks, 12 h of fasting reduced the mRNA levels of intestinal CCK, PYY, Y2 receptor, and pancreatic PYY, and these changes were reversed by 12 h of re-feeding. On the other hand, in broiler chicks 12 h of fasting reduced the mRNA levels of intestinal PYY and Y2 receptor, but not intestinal CCK and pancreatic PYY, and these changes were reversed by 12 h of re-feeding. Hypothalamic NPY mRNA significantly increased by 12 h of fasting in both chicks, and these changes were reversed by re-feeding. Also, 12 h of fasting significantly increased the mRNA levels of hypothalamic agouti-related protein and reduced the mRNA levels of hepatic IGF-1 only in broiler chicks, and 12 h of re-feeding did not change these. IGFBP-1 and -2 mRNA levels were markedly increased by 12 h of fasting in both chicks, and these changes were reversed by re-feeding. IGFBP-3 mRNA levels were increased by 12 h of fasting only in layer chicks, while re-feeding reduced the mRNA levels of IGFBP-3 in both types of chicks. These results suggest that several peripheral hormones, such as pancreatic PYY and intestinal CCK, may not play important roles in the regulation of food intake in broiler chicks.


Assuntos
Colecistocinina/metabolismo , Jejum/fisiologia , Pâncreas/metabolismo , Peptídeo YY/fisiologia , Animais , Regulação do Apetite , Galinhas , Ingestão de Alimentos/fisiologia , Comportamento Alimentar , Privação de Alimentos , Regulação da Expressão Gênica , Hormônios/metabolismo , Hiperfagia , Hipotálamo/metabolismo , Íleo/metabolismo , Masculino , Neuropeptídeos/metabolismo
7.
Eur J Clin Pharmacol ; 77(5): 651-657, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33244632

RESUMO

PURPOSE: SGLT2-inhibitors (SGLT-2i) have been linked to the risk of potential life-threatening diabetic ketoacidosis (DKA). The U.S. Food and Drug Administration and the European Medicines Agency issued warnings in 2015 and 2016 respectively on the predisposing factors to the development of DKA in individuals on an SGLT2i. New predisposing factors to DKA are still being discovered with the use of SGLT-2i. The list by FDA and EMA is yet to be updated. This article aims to provide a holistic list that includes the newer factors that have been implicated in the development of DKA. The overall aim is to guide physicians in prescribing this class of drugs for type 2 diabetes mellitus (T2D). METHOD: A search was done using PUBMED, Google Scholar, and Directory of Open Access Journals with the following words: SGLT-2 Inhibitors AND Ketoacidosis were entered. We included articles from 2000 to 2020, those in English, those involving any of the approved SGLT2i medications in T2D patients, and studies that focused on DKA linked to SGLT-2i. These articles were reviewed, and relevant data extracted and compiled. RESULTS AND CONCLUSION: The review has revealed that predisposing factors include (excess) alcohol consumption, female gender, starvation due to illness or fasting, withholding the use of SGLT2i for less than 48 h peri-operatively, and the existence of a variations in the expression of SGLT2 receptors. Patients should be advised on "sick day rules," and if a patient becomes unwell while on an SGLT2i, they should be advised to withhold the medication for the duration of the intercurrent illness.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Cetoacidose Diabética/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Jejum/fisiologia , Predisposição Genética para Doença , Nível de Saúde , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/administração & dosagem , Fatores de Risco , Fatores Sexuais , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos
8.
Diabetes Res Clin Pract ; 172: 108530, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33157118

RESUMO

AIMS: This narrative review aimed to synthesize the evidence on the effects of Ramadan-focused nutrition therapy for people with diabetes. METHODS: We searched MEDLINE (via PubMed) and Science Direct databases for articles that included the component of nutrition for adult patients with type 2 diabetes (T2D), published in English between 2010 and 2020. RESULTS: Fourteen studies met the criteria. Eight of 14 studies had an intervention with a control arm. In comparison to the control group, all studies (n = 8) showed a reduction in hypoglycemic events. However, only half of these studies (n = 4) had shown at least one positive clinical outcome. Features of nutrition therapy that appeared to have favorable clinical outcomes include individualized caloric prescription; distributing carbohydrates equally between Suhoor, Iftar and snacks; providing meal plans; adjusting food intake to suit Ramadan; and incorporating diabetes-specific formula as part of Suhoor or snack. CONCLUSIONS: The review provides evidence for the effectiveness of Ramadan-focused nutrition therapy among people with T2D and identifies key features of nutrition therapy that may provide favourable clinical outcomes. Additional data on dietary quality and adequacy during Ramadan fasting warrants further studies.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Jejum/fisiologia , Terapia Nutricional/métodos , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Islamismo , Masculino
9.
Clin Nutr ; 40(4): 1699-1710, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32980186

RESUMO

INTRODUCTION: l-arginine supplementation may improve vascular endothelial function. As tree nuts and groundnuts are a source of the amino acid l-arginine, we performed a meta-analysis of human randomized controlled trials (RCTs) to compare effects of tree nut and groundnut consumption with those of l-arginine supplementation on fasting and postprandial endothelial function as assessed by flow-mediated vasodilation of the brachial artery (FMD). METHODS: Summary estimates of weighted mean differences (WMDs) in FMD and 95% confidence intervals (CIs) were calculated using random-effect meta-analyses. RESULTS: A total of thirteen RCTs focusing on tree nut and groundnut consumption and nineteen RCTs investigating effects of l-arginine supplementation were included. Longer-term consumption of tree nuts and groundnuts increased fasting FMD by 1.09 %-point (PP) (95% CI: 0.49, 1.69, P < 0.001; I2: 76.7%, P < 0.001), while l-arginine supplementation (daily range: 3-21 g) increased fasting FMD by 0.53 PP (95% CI: 0.12, 0.93; P = 0.012; I2: 91.6%, P < 0.001). Effects between treatments were not statistically different (P = 0.31). Tree nut and groundnut consumption did not affect postprandial FMD responses (1.25 PP, 95% CI: -0.31, 2.81, P = 0.12; I2: 91.4%, P < 0.001), whereas l-arginine supplementation (range: 3-15 g) improved FMD during the postprandial phase by 2.02 PP (95% CI: 0.92, 3.13, P < 0.001; I2: 99.1%, P < 0.001). However, treatment effects did not differ significantly (P = 0.60). Overall, these results derive from high-quality evidence. CONCLUSION: Longer-term consumption of tree nuts and groundnuts, as well as l-arginine supplementation did improve fasting endothelial function, as assessed by FMD. However, the positive effects of tree nuts and groundnuts could not be fully explained by the amount of l-arginine in these nuts. Only l-arginine supplementation did improve postprandial FMD, but effects were not different from those of tree nuts and groundnuts. Future studies should focus on the identifications of the bioactive nutrients in tree nuts and groundnuts and mechanistic pathways behind differences in postprandial and longer-term fasting changes in FMD.


Assuntos
Arginina/farmacologia , Suplementos Nutricionais , Jejum/fisiologia , Nozes , Período Pós-Prandial/fisiologia , Vasodilatação/fisiologia , Dieta/métodos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Int J Mol Sci ; 21(22)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233502

RESUMO

Under normal physiological conditions the brain primarily utilizes glucose for ATP generation. However, in situations where glucose is sparse, e.g., during prolonged fasting, ketone bodies become an important energy source for the brain. The brain's utilization of ketones seems to depend mainly on the concentration in the blood, thus many dietary approaches such as ketogenic diets, ingestion of ketogenic medium-chain fatty acids or exogenous ketones, facilitate significant changes in the brain's metabolism. Therefore, these approaches may ameliorate the energy crisis in neurodegenerative diseases, which are characterized by a deterioration of the brain's glucose metabolism, providing a therapeutic advantage in these diseases. Most clinical studies examining the neuroprotective role of ketone bodies have been conducted in patients with Alzheimer's disease, where brain imaging studies support the notion of enhancing brain energy metabolism with ketones. Likewise, a few studies show modest functional improvements in patients with Parkinson's disease and cognitive benefits in patients with-or at risk of-Alzheimer's disease after ketogenic interventions. Here, we summarize current knowledge on how ketogenic interventions support brain metabolism and discuss the therapeutic role of ketones in neurodegenerative disease, emphasizing clinical data.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Glucose/metabolismo , Corpos Cetônicos/metabolismo , Neurônios/metabolismo , Doença de Parkinson/metabolismo , Trifosfato de Adenosina/biossíntese , Doença de Alzheimer/dietoterapia , Doença de Alzheimer/patologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Dieta Cetogênica/métodos , Jejum/fisiologia , Glicólise/efeitos dos fármacos , Humanos , Corpos Cetônicos/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/dietoterapia , Doença de Parkinson/patologia , Roedores
11.
AAPS J ; 22(6): 134, 2020 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-33070288

RESUMO

A physiologically based pharmacokinetic (PBPK) human model for alpelisib, an oral α-specific class I phosphatidylinositol-3-kinase (PI3K) inhibitor, was established to simulate oral absorption and plasma pharmacokinetics of healthy subjects to allow model-informed drug development. The GastroPlus™ model consisted of an advanced absorption gut model, which was linked to a 2-compartmental model. Systemic clearance and volume of distribution were estimated using population pharmacokinetics (popPK). Various food effect and pH-mediated absorption drug-drug interaction (DDI) scenarios were modeled. In fasted healthy subjects, simulated absorption was lower (ca. 70% for a 300-mg dose) due to pH and bile acid concentration-dependent solubility. Ranitidine showed a significant pH-mediated DDI effect only in the fasted but not fed state. The PBPK model identified that more drug is absorbed in the fed state, and alpelisib intestinal permeability is rate limiting to systemic exposure. Simulations for healthy subject showed a positive food effect with ca. 2-fold increase in plasma Cmax and 1.5-fold increase in AUC0-inf with a meal compared with fasted conditions. The PBPK model was verified using clinical food effect data with pivotal clinical formulation (PCF) and then applied to predict the performance of a commercial formulation (CF) in healthy volunteers. The model successfully predicted the outcome of a clinical bioequivalence study for PCF and CF with included in vitro dissolution data, both fasted and fed state. Estimated predictive errors (based on plasma Cmax, AUC0-t) were equal or below 30%. The alpelisib model for healthy subjects enables future bioequivalence formulation assessments, in fasted, fed, or altered pH conditions. Graphical Abstract.


Assuntos
Interações Alimento-Droga , Absorção Intestinal/fisiologia , Modelos Biológicos , Inibidores de Fosfoinositídeo-3 Quinase/farmacocinética , Tiazóis/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Disponibilidade Biológica , Células CACO-2 , Estudos Cross-Over , Cães , Avaliação Pré-Clínica de Medicamentos , Jejum/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Masculino , Permeabilidade , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/administração & dosagem , Inibidores de Fosfoinositídeo-3 Quinase/efeitos adversos , Ratos , Solubilidade , Comprimidos , Equivalência Terapêutica , Tiazóis/administração & dosagem , Tiazóis/efeitos adversos , Adulto Jovem
12.
Ann Nutr Metab ; 76(5): 297-303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32950986

RESUMO

BACKGROUND: COVID-19 pandemic, a global threat, adversely affects all daily lives, altered governmental plans around the world, and urges the development of therapeutics and prophylactics to avoid the expansion of the viral infection. With the recent gradual opening after long lockdown, several recommendations have been placed, with dietary modification as one of the most important approaches that have been appraised. SUMMARY: Here, we are reviewing how changing the host metabolism, particularly changing the host metabolic state from the carbohydrate-dependent glycolytic state to a fat-dependent ketogenic state, may affect viral replication. Furthermore, the impact of intermittent fasting (IF) in triggering metabolic switch along with the impact of supplementation with medium-chain triglycerides (MCTs) such as lauric acid in repressing the envelope formation and viral replication is also addressed. The amalgamation of IF and a ketogenic diet rich in MCTs is thought to work as a prophylactic measure for normal people and adjunct therapy for infected persons. Key Message: A diet regimen of ketogenic breakfast along with supplementation with two doses of lauric acid-rich MCTs at breakfast and lunch times, followed by 8-12-h IF and a dinner rich with fruits and vegetables, could be a potential prophylactic strategy and adjuvant therapy to combat SARS-CoV-2 infections.


Assuntos
COVID-19/metabolismo , Controle de Doenças Transmissíveis/métodos , Dieta Cetogênica/métodos , Jejum/metabolismo , Replicação Viral/fisiologia , Jejum/fisiologia , Humanos , Pandemias , Triglicerídeos/administração & dosagem , Triglicerídeos/metabolismo
13.
Nature ; 583(7817): 620-624, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32669709

RESUMO

Approximately 75% of all breast cancers express the oestrogen and/or progesterone receptors. Endocrine therapy is usually effective in these hormone-receptor-positive tumours, but primary and acquired resistance limits its long-term benefit1,2. Here we show that in mouse models of hormone-receptor-positive breast cancer, periodic fasting or a fasting-mimicking diet3-5 enhances the activity of the endocrine therapeutics tamoxifen and fulvestrant by lowering circulating IGF1, insulin and leptin and by inhibiting AKT-mTOR signalling via upregulation of EGR1 and PTEN. When fulvestrant is combined with palbociclib (a cyclin-dependent kinase 4/6 inhibitor), adding periodic cycles of a fasting-mimicking diet promotes long-lasting tumour regression and reverts acquired resistance to drug treatment. Moreover, both fasting and a fasting-mimicking diet prevent tamoxifen-induced endometrial hyperplasia. In patients with hormone-receptor-positive breast cancer receiving oestrogen therapy, cycles of a fasting-mimicking diet cause metabolic changes analogous to those observed in mice, including reduced levels of insulin, leptin and IGF1, with the last two remaining low for extended periods. In mice, these long-lasting effects are associated with long-term anti-cancer activity. These results support further clinical studies of a fasting-mimicking diet as an adjuvant to oestrogen therapy in hormone-receptor-positive breast cancer.


Assuntos
Neoplasias da Mama/dietoterapia , Neoplasias da Mama/tratamento farmacológico , Dietoterapia/métodos , Jejum/fisiologia , Fulvestranto/uso terapêutico , Animais , Fatores Biológicos/sangue , Neoplasias da Mama/patologia , Dieta Saudável/métodos , Modelos Animais de Doenças , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Fulvestranto/administração & dosagem , Humanos , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/sangue , Células MCF-7 , Camundongos Endogâmicos NOD , Camundongos SCID , PTEN Fosfo-Hidrolase/metabolismo , Piperazinas/administração & dosagem , Piperazinas/uso terapêutico , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Receptores de Estrogênio , Receptores de Progesterona , Tamoxifeno/efeitos adversos , Tamoxifeno/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Horm Behav ; 125: 104820, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32710887

RESUMO

Food availability affects metabolism and reproduction in higher vertebrates including birds. This study tested the idea of adaptive homeostasis to time-restricted feeding (TRF) in diurnal zebra finches by using multiple (behavioral, physiological and molecular) assays. Adult birds were subjected for 1 week or 3 weeks to food restriction for 4 h in the evening (hour 8-12) of the 12 h light-on period, with controls on ad lib feeding. Birds on TRF showed enhanced exploratory behavior and plasma triglycerides levels, but did not show differences from ad lib birds in the overall food intake, body mass, and plasma corticosterone and thyroxine levels. As compared to ad lib feeding, testis size and circulation testosterone were reduced after first but not after third week of TRF. The concomitant change in the mRNA expression of metabolic and reproductive genes was also found after week 1 of TRF. Particularly, TRF birds showed increased expression of genes coding for gonadotropin releasing hormone (GnRH) in hypothalamus, and for receptors of androgen (AR) and estrogen (ER-alpha) in both hypothalamus and testes. However, genes coding for the deiodinases (Dio2, Dio3) and gonadotropin inhibiting hormone (GnIH) showed no difference between feeding conditions in both hypothalamus and testes. Further, increased Sirt1, Fgf10 and Ppar-alpha, and decreased Egr1 expression in the liver suggested TRF-effects on the overall metabolism. Importantly, TRF-effects on gene expressions by week 1 seemed alleviated to a considerable extent by week 3. These results on TRF-induced reproductive and metabolic effects suggest homeostatic adaptation to food-restriction in diurnal vertebrates.


Assuntos
Metabolismo Energético/fisiologia , Tentilhões/fisiologia , Privação de Alimentos/fisiologia , Reprodução/fisiologia , Adaptação Fisiológica/fisiologia , Animais , Ritmo Circadiano/fisiologia , Corticosterona/sangue , Jejum/fisiologia , Tentilhões/metabolismo , Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Homeostase/fisiologia , Hipotálamo/metabolismo , Iodeto Peroxidase/genética , Iodeto Peroxidase/metabolismo , Masculino , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Testículo/metabolismo , Testosterona/sangue , Fatores de Tempo , Vertebrados/fisiologia
15.
Lipids Health Dis ; 19(1): 87, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32384902

RESUMO

BACKGROUND: Previous studies have yielded inconsistent findings on the role of fish oil in type 2 diabetes mellitus (T2DM). We systematically summarized the available evidence from randomized controlled trials (RCT) and aimed to investigate the effects of fish oil supplementation on glucose control and lipid levels among patients with T2DM. METHODS: A comprehensive literature search was performed in electronic databases (PubMed, ProQuest, Cochrane Library, CNKI, VIP, and Wanfang) to identify all relevant RCTs which were published up to May 31st, 2019. We used Modified Jadad Score system to evaluate the quality of each included RCT. The pooled effects were estimated using random-effects model and presented as standardized mean differences with 95% confidence intervals. RESULTS: A total of 12 RCTs were included in this meta-analysis. There was no significant difference in glucose control outcomes comparing fish oil supplementation to placebo. The effect size of fasting plasma glucose (FPG) was 0.13 (95% CI: - 0.03 to 0.28, p > 0.05). No marked change was observed in fasting insulin (FINS), glycosylated hemoglobin (HbA1c), and HOMA of insulin resistance (HOMA-IR) levels. Fish oil supplementation was associated with a decrease of triglyceride (TG) level by - 0.40 (95%CI: - 0.53 to - 0.28, p < 0.05), and an increase of high density lipoprotein (HDL) cholesterol level by 0.21 (95%CI: 0.05 to 0.37, p < 0.05). In subgroup analysis, HDL cholesterol level was higher among Asian and low-dose(< 2 g/d n-3 PUFA) subgroups compared to their counterparts (p < 0.05). TG level was lower in mid and long duration groups, along with an inconspicuous difference in short duration group. CONCLUSIONS: This meta-analysis shows that among patients with T2DM, fish oil supplementation leads to a favorable blood lipids profile but does not improve glucose control.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/dietoterapia , Suplementos Nutricionais , Óleos de Peixe/administração & dosagem , Insulina/sangue , Adulto , Idoso , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Jejum/fisiologia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Triglicerídeos/sangue
16.
Neuroimage ; 217: 116931, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32417450

RESUMO

The hypothalamus and insular cortex play an essential role in the integration of endocrine and homeostatic signals and their impact on food intake. Resting-state functional connectivity alterations of the hypothalamus, posterior insula (PINS) and anterior insula (AINS) are modulated by metabolic states and caloric intake. Nevertheless, a deeper understanding of how these factors affect the strength of connectivity between hypothalamus, PINS and AINS is missing. This study investigated whether effective (directed) connectivity within this network varies as a function of prandial states (hunger vs. satiety) and energy availability (glucose levels and/or hormonal modulation). To address this question, we measured twenty healthy male participants of normal weight twice: once after 36 â€‹h of fasting (except water consumption) and once under satiated conditions. During each session, resting-state functional MRI (rs-fMRI) and hormone concentrations were recorded before and after glucose administration. Spectral dynamic causal modeling (spDCM) was used to assess the effective connectivity between the hypothalamus and anterior and posterior insula. Using Bayesian model selection, we observed that the same model was identified as the most likely model for each rs-fMRI recording. Compared to satiety, the hunger condition enhanced the strength of the forward connections from PINS to AINS and reduced the strength of backward connections from AINS to PINS. Furthermore, the strength of connectivity from PINS to AINS was positively related to plasma cortisol levels in the hunger condition, mainly before glucose administration. However, there was no direct relationship between glucose treatment and effective connectivity. Our findings suggest that prandial states modulate connectivity between PINS and AINS and relate to theories of interoception and homeostatic regulation that invoke hierarchical relations between posterior and anterior insula.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Glucose/farmacologia , Fome/fisiologia , Hipotálamo/diagnóstico por imagem , Hipotálamo/fisiologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Resposta de Saciedade/fisiologia , Administração Oral , Adulto , Teorema de Bayes , Glicemia/metabolismo , Mapeamento Encefálico , Jejum/fisiologia , Glucose/administração & dosagem , Humanos , Interocepção/fisiologia , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Adulto Jovem
17.
Nutrients ; 12(4)2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32283820

RESUMO

The objective of the present study is to analyze the effects of motor mental imagery training on tennis service performance among tennis athletes who fast during Ramadan. Participants were 38 young male tennis players, randomly divided into two groups: Imaging Training (IMG, n = 18) and control group (CG, n = 20). The CG has watched videos on the history of the Olympic Games, while IMG has followed a training program in motor imagery. The performance of the tennis service was obtained by the product between accuracy and speed of typing (accuracy x average speed of all shots (km/h)). The effect of group / time interaction (p < 0.01) was identified for all performance indicators (accuracy, running speed and performance (speed x precision)), with improvement only in IMG (p = 0.01). The results showed that motor imagery training could be an effective strategy for mitigating/counteracting the negative effects of Ramadan on the tennis service performance.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Jejum/fisiologia , Imaginação , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Desempenho Psicomotor/fisiologia , Religião , Tênis/fisiologia , Tênis/psicologia , Adolescente , Humanos , Masculino
18.
Nature ; 579(7800): 507-517, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32214253

RESUMO

Tumours depend on nutrients supplied by the host for their growth and survival. Modifications to the host's diet can change nutrient availability in the tumour microenvironment, which might represent a promising strategy for inhibiting tumour growth. Dietary modifications can limit tumour-specific nutritional requirements, alter certain nutrients that target the metabolic vulnerabilities of the tumour, or enhance the cytotoxicity of anti-cancer drugs. Recent reports have suggested that modification of several nutrients in the diet can alter the efficacy of cancer therapies, and some of the newest developments in this quickly expanding field are reviewed here. The results discussed indicate that the dietary habits and nutritional state of a patient must be taken into account during cancer research and therapy.


Assuntos
Dieta , Neoplasias/dietoterapia , Neoplasias/terapia , Estado Nutricional , Aminoácidos/deficiência , Aminoácidos/metabolismo , Animais , Suplementos Nutricionais , Jejum/fisiologia , Ácidos Graxos/metabolismo , Ácido Fólico/metabolismo , Frutose/deficiência , Frutose/metabolismo , Glucose/metabolismo , Humanos , Neoplasias/metabolismo , Neoplasias/patologia
19.
Nutrients ; 12(3)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121154

RESUMO

The present study verified the responses of proteins related to the autophagy pathway after 10 h of fast with resistance exercise and protein ingestion in skeletal muscle and liver samples. The rats were distributed into five experimental groups: control (CT; sedentary and without gavage after fast), exercise immediately (EXE-imm; after fast, rats were submitted to the resistance protocol and received water by gavage immediately after exercise), exercise after 1 h (EXE-1h; after fast, rats were submitted to the resistance protocol and received water by gavage 1 h after exercise), exercise and supplementation immediately after exercise (EXE/Suppl-imm; after fast, rats were submitted to the resistance protocol and received a mix of casein: whey protein 1:1 (w/w) by gavage immediately after exercise), exercise and supplementation 1 h after exercise (EXE/Suppl-1h; after fast, rats were submitted to the resistance protocol and received a mix of casein: whey protein 1:1 (w/w) by gavage 1 h after exercise). In summary, the current findings show that the combination of fasting, acute resistance exercise, and protein blend ingestion (immediately or 1 h after the exercise stimulus) increased the serum levels of leucine, insulin, and glucose, as well as the autophagy protein contents in skeletal muscle, but decreased other proteins related to the autophagic pathway in the liver. These results deserve further mechanistic investigations since athletes are combining fasting with physical exercise to enhance health and performance outcomes.


Assuntos
Autofagia , Biomarcadores/metabolismo , Proteínas Alimentares/administração & dosagem , Jejum/fisiologia , Fígado/metabolismo , Músculo Esquelético/metabolismo , Condicionamento Físico Animal , Treinamento Resistido , Albuminas/metabolismo , Animais , Autofagia/efeitos dos fármacos , Autofagia/genética , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Proteínas Alimentares/farmacologia , Ingestão de Alimentos , Jejum/sangue , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/sangue , Leucina/sangue , Fígado/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Triglicerídeos/sangue
20.
J Sports Sci ; 38(7): 795-800, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32122273

RESUMO

Mouth rinsing has been proposed as a strategy to minimize performance decrements during Ramadan. We investigated the effect of 4 weeks of Ramadan on kicking performance in 27 Taekwondo athletes performing weekly Taekwondo Anaerobic Intermittent Kick Tests (TAIKT). The effects of a placebo, 6.4% glucose and 6-mg/kg caffeine mouth rinses on TAIKT performance and perceived exertion were investigated before, during weekly training sessions, and after Ramadan in a counterbalanced, crossover design. Ramadan had a significant negative impact on the percentage of successful kicks in Week 1 of Ramadan (pre: 76.7±0.4%, Week 1: 69.9±3.2%). The percentage of successful kicks was significantly greater in the caffeine mouth rinse condition compared to the glucose and placebo conditions during the first 3 weeks of Ramadan (caffeine: 38.3±6.8%, glucose: 36.4±6.9%, placebo: 36.0±6.5%). Caffeine decreased perceived exertion during Ramadan (0.74-1.15 AU, p>0.05). Our results showed that Ramadan had a significant negative effect on repeated high-intensity kicking efforts that should be considered when training and competing. Additionally, there were significant positive effects of a caffeine mouth rinse in a sport-specific test. These data suggest that athletes can consider mouth rinsing as a strategy to enhance performance when undertaking training or competition during a period of privation.


Assuntos
Desempenho Atlético/fisiologia , Cafeína/administração & dosagem , Açúcares da Dieta/administração & dosagem , Jejum/fisiologia , Islamismo , Artes Marciais/fisiologia , Antissépticos Bucais , Adolescente , Adulto , Comportamento Competitivo/fisiologia , Estudos Cross-Over , Feminino , Humanos , Masculino , Percepção/fisiologia , Condicionamento Físico Humano , Esforço Físico/fisiologia , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA