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2.
Cell ; 132(3): 375-86, 2008 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-18267070

RESUMEN

Type 2 (non-insulin-dependent) diabetes mellitus is a progressive metabolic disorder arising from genetic and environmental factors that impair beta cell function and insulin action in peripheral tissues. We identified reduced diacylglycerol kinase delta (DGKdelta) expression and DGK activity in skeletal muscle from type 2 diabetic patients. In diabetic animals, reduced DGKdelta protein and DGK kinase activity were restored upon correction of glycemia. DGKdelta haploinsufficiency increased diacylglycerol content, reduced peripheral insulin sensitivity, insulin signaling, and glucose transport, and led to age-dependent obesity. Metabolic flexibility, evident by the transition between lipid and carbohydrate utilization during fasted and fed conditions, was impaired in DGKdelta haploinsufficient mice. We reveal a previously unrecognized role for DGKdelta in contributing to hyperglycemia-induced peripheral insulin resistance and thereby exacerbating the severity of type 2 diabetes. DGKdelta deficiency causes peripheral insulin resistance and metabolic inflexibility. These defects in glucose and energy homeostasis contribute to mild obesity later in life.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Diacilglicerol Quinasa/metabolismo , Regulación hacia Abajo , Resistencia a la Insulina , Adulto , Envejecimiento , Animales , Diacilglicerol Quinasa/genética , Diglicéridos/metabolismo , Metabolismo Energético , Perfilación de la Expresión Génica , Glucosa/metabolismo , Humanos , Hiperglucemia/metabolismo , Metabolismo de los Lípidos , Masculino , Ratones , Músculo Esquelético/metabolismo , Obesidad , Proteína Quinasa C/metabolismo , Ratas , Ratas Wistar , Transducción de Señal
3.
Cardiovasc Diabetol ; 20(1): 118, 2021 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-34107965

RESUMEN

BACKGROUND: Information about the renin-angiotensin-aldosterone system (RAAS) in obese individuals before and after bariatric surgery is scarce. Aim of this study was to analyze the RAAS in severely obese subjects, in relation to anthropometric and metabolic variables, with special reference to glucose tolerance. METHODS: 239 subjects were evaluated at baseline, and 181 one year after bariatric surgery [laparoscopic gastric banding (LAGB)]. RESULTS: At baseline, renin (plasma renin activity, PRA) was increased from normal to glucose tolerance and more in diabetes, also correlating with ferritin. After LAGB, the decrease of PRA and aldosterone was significant in hypertensive, but not in normotensive subjects, and correlatied with decrease of ferritin. PRA and glucose levels were predictive of persistent hypertension 1 year after LAGB. CONCLUSIONS: These data support the role of RAAS in the pathophysiology of glucose homeostasis, and in the regulation of blood pressure in obesity. Ferritin, as a proxy of subclinical inflammation, could be another factor contributing to the cross-talk between RAAS and glucose metabolism.


Asunto(s)
Presión Arterial , Gastroplastia , Hipertensión/sangre , Laparoscopía , Obesidad/cirugía , Sistema Renina-Angiotensina , Renina/sangre , Adulto , Biomarcadores/sangre , Glucemia/metabolismo , Femenino , Humanos , Hipertensión/diagnóstico , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/diagnóstico , Obesidad/fisiopatología , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Pérdida de Peso
4.
Int J Mol Sci ; 21(24)2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33371208

RESUMEN

Inflammation is a common feature of several diseases, including obesity, diabetes and neurodegenerative disorders. Circadian clock genes are expressed and oscillate in many cell types such as macrophages, neurons and pancreatic ß cells. During inflammation, these endogenous clocks control the temporal gating of cytokine production, the antioxidant response, chemokine attraction and insulin secretion, among other processes. Deletion of clock genes in macrophages or brain-resident cells induces a higher production of inflammatory cytokines and chemokines, and this is often accompanied by an increased oxidative stress. In the context of obesity and diabetes, a high-fat diet disrupts the function of clock genes in macrophages and in pancreatic ß cells, contributing to inflammation and systemic insulin resistance. Recently, it has been shown that the administration of natural and synthetic ligands or pharmacological enhancers of the circadian clock function can selectively regulate the production and release of pro-inflammatory cytokines and improve the metabolic function in vitro and in vivo. Thus, a better understanding of the circadian regulation of the immune system could have important implications for the management of metabolic and neurodegenerative diseases.


Asunto(s)
Proteínas CLOCK/genética , Relojes Circadianos , Diabetes Mellitus/patología , Sistema Inmunológico/inmunología , Inflamación/inmunología , Enfermedades Neurodegenerativas/patología , Obesidad/patología , Animales , Diabetes Mellitus/etiología , Humanos , Inflamación/fisiopatología , Enfermedades Neurodegenerativas/etiología , Obesidad/etiología
5.
J Physiol ; 597(15): 3905-3925, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31210356

RESUMEN

KEY POINTS: Cancer growth, cell proliferation and cachexia index can be attenuated by the beneficial programming effect of moderate exercise training, especially if it begins in adolescence. Walker 256 tumour-bearing rats who started exercise training during adolescence did not revert the basal low glycaemia and insulinaemia observed before tumour cell inoculation. The moderate exercise training improved glucose tolerance and peripheral insulin sensitivity only in rats exercised early in adolescence. The chronic effects of our exercise protocol are be beneficial to prevent cancer cachexia and hold clear potential as a nonpharmacological therapy of insulin sensitization. ABSTRACT: We tested the hypothesis that moderate exercise training, performed early, starting during adolescence or later in life during adulthood, can inhibit tumour cell growth as a result of changes in biometric and metabolic markers. Male rats that were 30 and 70 days old performed a treadmill running protocol over 8 weeks for 3 days week-1 , 44 min day-1 and at 55-65% V̇O2max . After the end of training, a batch of rats was inoculated with Walker 256 carcinoma cells. At 15 days after carcinoma cell inoculation, the tumour was weighed and certain metabolic parameters were evaluated. The data demonstrated that physical performance was better in rats that started exercise training during adolescence according to the final workload and V̇O2max . Early or later moderate exercise training decreased the cachexia index, cell proliferation and tumour growth; however, the effects were more pronounced in rats that exercised during adolescence. Low glycaemia, insulinaemia and tissue insulin sensitivity was not reverted in Walker 256 tumour-bearing rats who trained during adolescence. Cancer growth can be attenuated by the beneficial programming effect of moderate exercise training, especially if it begins during adolescence. In addition, improvement in glucose-insulin homeostasis might be involved in this process.


Asunto(s)
Carcinoma 256 de Walker/terapia , Condicionamiento Físico Animal/métodos , Animales , Caquexia/metabolismo , Caquexia/prevención & control , Carcinoma 256 de Walker/patología , Carcinoma 256 de Walker/prevención & control , Células Cultivadas , Glucosa/metabolismo , Resistencia a la Insulina , Masculino , Ratas , Ratas Wistar
6.
Eur J Nutr ; 57(2): 477-486, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27752755

RESUMEN

PURPOSE: Environmental and nutritional disorders during perinatal period cause metabolic dysfunction in the progeny and impair human health. Advanced glycation end products (AGEs) are primarily produced during metabolism of excess blood glucose, which is observed in diabetes. Methylglyoxal (MG) is a precursor for the generation of endogenous AGEs, which disturbs the metabolism. This work aimed to investigate whether the maternal MG treatment during lactation programs the progeny to metabolic dysfunction later in life. METHODS: Female Wistar rats were divided into two groups: control group (C) treated with saline and MG group treated with MG (60 mg/kg/day) by gavage throughout the lactation period. Both mothers and offspring were fed a standard chow. At weaning, breast milk composition was analyzed and mothers euthanized for blood and tissue sample collections. At 90 days of age, offspring were submitted to glucose tolerance test (ivGTT) and euthanized for blood and tissue samples collection. RESULTS: MG mothers showed increase in glucose and fructosamine levels; however, they showed low insulin levels and failure in ß-cell function (p < 0.05). MG mothers also showed dyslipidemia (p < 0.05). Moreover, breast milk had elevated levels of glucose, triglycerides, cholesterol and fructosamine and low insulin (p < 0.05). Interestingly, MG offspring had increased body weight and adipose tissue at adulthood, and they also showed glucose intolerance and failure in ß-cell function (p < 0.05). Besides, MG offspring showed dyslipidemia (p < 0.05) increasing cardiovascular diseases risk. CONCLUSIONS: Maternal MG treatment negatively affects the male rat offspring, leading to type 2 diabetes and dyslipidemia in later life, possibly by changes in breast milk composition.


Asunto(s)
Diabetes Mellitus Tipo 2/inducido químicamente , Dislipidemias/inducido químicamente , Contaminantes Ambientales/toxicidad , Lactancia/efectos de los fármacos , Exposición Materna/efectos adversos , Obesidad/inducido químicamente , Piruvaldehído/toxicidad , Adiposidad/efectos de los fármacos , Administración Oral , Animales , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Dislipidemias/sangre , Dislipidemias/metabolismo , Dislipidemias/patología , Contaminantes Ambientales/administración & dosificación , Contaminantes Ambientales/análisis , Femenino , Insulina/análisis , Insulina/sangre , Insulina/metabolismo , Resistencia a la Insulina , Secreción de Insulina , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Grasa Intraabdominal/efectos de los fármacos , Grasa Intraabdominal/metabolismo , Grasa Intraabdominal/patología , Lactancia/metabolismo , Masculino , Leche/química , Obesidad/sangre , Obesidad/metabolismo , Obesidad/patología , Embarazo , Piruvaldehído/administración & dosificación , Piruvaldehído/análisis , Distribución Aleatoria , Ratas Sprague-Dawley , Toxicocinética , Aumento de Peso/efectos de los fármacos
7.
J Pineal Res ; 57(2): 155-67, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24981026

RESUMEN

Melatonin has a number of beneficial metabolic actions and reduced levels of melatonin may contribute to type 2 diabetes. The present study investigated the metabolic pathways involved in the effects of melatonin on mitochondrial function and insulin resistance in rat skeletal muscle. The effect of melatonin was tested both in vitro in isolated rats skeletal muscle cells and in vivo using pinealectomized rats (PNX). Insulin resistance was induced in vitro by treating primary rat skeletal muscle cells with palmitic acid for 24 hr. Insulin-stimulated glucose uptake was reduced by palmitic acid followed by decreased phosphorylation of AKT which was prevented my melatonin. Palmitic acid reduced mitochondrial respiration, genes involved in mitochondrial biogenesis and the levels of tricarboxylic acid cycle intermediates whereas melatonin counteracted all these parameters in insulin-resistant cells. Melatonin treatment increases CAMKII and p-CREB but had no effect on p-AMPK. Silencing of CREB protein by siRNA reduced mitochondrial respiration mimicking the effect of palmitic acid and prevented melatonin-induced increase in p-AKT in palmitic acid-treated cells. PNX rats exhibited mild glucose intolerance, decreased energy expenditure and decreased p-AKT, mitochondrial respiration, and p-CREB and PGC-1 alpha levels in skeletal muscle which were restored by melatonin treatment in PNX rats. In summary, we showed that melatonin could prevent mitochondrial dysfunction and insulin resistance via activation of CREB-PGC-1 alpha pathway. Thus, the present work shows that melatonin play an important role in skeletal muscle mitochondrial function which could explain some of the beneficial effects of melatonin in insulin resistance states.


Asunto(s)
Resistencia a la Insulina/fisiología , Melatonina/farmacología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Animales , Células Cultivadas , Ciclo del Ácido Cítrico/efectos de los fármacos , Prueba de Tolerancia a la Glucosa , Masculino , Consumo de Oxígeno/efectos de los fármacos , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos
8.
Pediatr Pulmonol ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38712796

RESUMEN

PURPOSE: Predicting bronchopulmonary dysplasia (BPD) to assess the risk-benefit of therapy is necessary considering the side effects of medications. We developed and validated an instrument for predicting BPD and compared it with an instrument currently used for neonates born in a Brazilian hospital. METHODS: This was a retrospective cohort study of patients born between 2016 and 2020 with a gestational age (GA) between 23 and 30 weeks. Predictive equations were elaborated using methods of component variable selection collected on the 14th day of life; 70% of the sample was randomly selected for the construction of risk prediction equations and the remaining 30% for their validation, application, and comparison with the National Institute of Child Health and Human Development (NICHD) instrument. The sensitivity, specificity, and predictive values of the equations were calculated. RESULTS: The equation that used variables with p < 5% in Fisher's exact test presented the best results: specificity of 98% and positive predictive value of 93% and could be used for BPD prediction of all small-for-gestational-age (SGA) infants. The NICHD calculator applied to our population had a specificity of 93% and a positive predictive value of 75% and could not be applied to extremely SGA infants. CONCLUSION: Our tool can predict the risk of BPD on the 14th day of life, has higher specificity and positive predictive value to our population than the NICHD instrument, and can be suitable for SGA infants. The results must be confirmed by applying it to other populations to validate our tool.

9.
Nutrition ; 103-104: 111776, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35964439

RESUMEN

OBJECTIVES: Maternal circadian eating time and frequency are associated with altered glucose metabolism during pregnancy in humans. Research on long maternal fasting intervals is inconclusive, and little is known about the effect of maternal time feeding on offspring health. Therefore, the aim of the present study is to determine whether maternal time feeding influences the metabolic status of both male and female offspring. METHODS: Pregnant rats were provided ad libitum access to chow diet or fed during either the light phase (LP) or dark phase (DP) during embryonic development. At the age of 150 days, glucose tolerance, lipid concentrations, and insulin secretion were determined in adult male and female offspring. RESULTS: Both male and female offspring of LP and DP dams exhibited alterations in the lipid profile, and female offspring were glucose intolerant. Glucose-stimulated insulin secretion decreased in male and female offspring of LP and DP dams. Acetylcholine increased insulin secretion in male and female offspring. Islets from male and female offspring of DP dams exhibited less pronounced inhibition of insulin secretion by epinephrine, suggesting alterations in the cholinergic and adrenergic pathways in these animals. CONCLUSIONS: Our data suggest that a time-restricted feeding regimen during embryonic development could program rat offspring for metabolic dysfunction during adulthood.


Asunto(s)
Insulina , Efectos Tardíos de la Exposición Prenatal , Embarazo , Humanos , Ratas , Masculino , Femenino , Animales , Adulto , Lactante , Insulina/metabolismo , Ayuno , Glucosa/metabolismo , Desarrollo Embrionario , Lípidos
10.
Chronobiol Int ; 38(8): 1177-1185, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33843407

RESUMEN

The study aimed to investigate the effects of time-of-day, chronotype, and sex differences on the relationships between anxiety, depression, sleep quality, and swimming performance of normally diurnally active adolescent athletes. Thirty-three competitive swimmers, 20 boys (14.8 ± 1.60 y) and 13 girls (14.4 ± 1.51 y) from two different swimming centers participate in the study. They performed 50 m and 400 m front crawl trials twice, at 08:00 h and 18:00 h, with an interval of 48 h in a 50 m swimming pool. Chronotype, depression, anxiety levels, and sleep quality were accessed by questionnaires. No effect of time-of-day was observed in girls for the 50 and 400 m trials. The swimming performance of boys was similar in the 50 m trials independent of time-of-day, but in the 400 m trial the performance time was better in the evening compared to morning. The best evening performance was observed among N-types. Linear regression analysis of the data of all participants revealed a positive correlation between sleep quality and anxiety level (p = .016; R2 = 0.1769) and sleep quality and depression level (p = .006; R2 = 0.2192). There was no correlation between chronotype and sleep quality in either sex (p = .4044; R2 = 0.0232). We conclude that time-of-day can influence the performance of adolescent swimmers that differs with the distance of the trial and by sex. We also demonstrated the importance of sleep quality among adolescents swimmers as a factor that can influence anxiety and depression and thus consequently affect their performance.


Asunto(s)
Ritmo Circadiano , Natación , Adolescente , Atletas , Femenino , Humanos , Masculino , Análisis de Regresión , Caracteres Sexuales
11.
J Endocrinol ; 252(2): 143-154, 2021 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-34647525

RESUMEN

Disruption of biological rhythms due to exposure to artificial light at night (ALAN) has emerged as a new risk factor for metabolic diseases. However, the effects of ALAN exposure on energy metabolism with concomitant misalignment in the circadian system caused by nutritional imbalance remain largely unexplored. Here, we evaluate whether a low-protein (LP) diet could enhance the effects induced by exposure to ALAN on the energy metabolism and consequently predispose to metabolic disorders. Male C57BL6/J mice were weaned on a normal protein (NP) or a LP diet and housed on 12 h light:12 h darkness (LD) cycle. After 6 weeks, mice maintained on their respective diets were subdivided into normal light/darkness cycle (NP/LD; LP/LD) or exposed to ALAN (NP/LL; LP/LL) for 8 weeks. We observed that exposure to ALAN concomitant to LP diet disrupts the behavioral rhythms, without shifting the timing of food intake. Furthermore, exposure to ALAN leads to increased body and fat pad weights, higher levels of fast and fed glycemia and glucose intolerance independent of the diet consumed. Importantly, the effects of ALAN on circadian regulation of insulin sensitivity were diet-dependent with LP/LL mice showing insulin resistance in an opposite time of day than NP/LL. At the molecular level, exposure to ALAN concurrent with LP diet increased the expression of phosphoenolpyruvate carboxykinase 1 in both periods analyzed and inverted the pattern of fibroblast growth factor 21 (Fgf21) expression in the liver. Our data suggest that dietary protein restriction modulates the effects induced by nighttime light exposure on glucose metabolism, which could be partially related with the dysregulation of hepatic Fgf21 expression.


Asunto(s)
Ritmo Circadiano , Dieta con Restricción de Proteínas/efectos adversos , Ingestión de Energía , Intolerancia a la Glucosa/etiología , Contaminación Lumínica/efectos adversos , Animales , Glucemia , Factores de Crecimiento de Fibroblastos/metabolismo , Glucosa/metabolismo , Resistencia a la Insulina , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Hígado/metabolismo , Masculino , Ratones Endogámicos C57BL , Actividad Motora , Obesidad/etiología , Fosfoenolpiruvato Carboxiquinasa (GTP)/metabolismo
12.
Heart Lung ; 50(5): 714-719, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34107396

RESUMEN

BACKGROUND: Pulmonary hypertension is a progressive, and disabling disease, however, there is little knowledge about impaired sexual function in this population. AIM: To identify the prevalence of sexual dysfunction and the association between sexual dysfunction level and sociodemographic and clinical characteristics. METHODS: A cross-sectional study with 71 women diagnosed with pulmonary hypertension without signs of clinical decompensation was carried out. Sexual function was assessed using the Female Sexual Function Index (FSFI) and functional capacity was assessed by 6-minute walk test. The relationships between sociodemographic and clinical characteristics with sexual function was performed using statistical tests. A p-value <0.05 was considered as significant. RESULTS: 71.8% of patients self-reported sexual dysfunction as indicated as a score of <26.55 points on FSFI. Women with sexual dysfunction were older, higher average age of their last menstruation, had worse functional class, shorter distance covered and worse Borg score at the end of the 6-minute walk test. CONCLUSION: There is evident impairment of sexual function self-reported by women with pH and the association of this condition with a decline in functional capacity was identified.


Asunto(s)
Hipertensión Pulmonar , Estudios Transversales , Femenino , Humanos , Hipertensión Pulmonar/epidemiología , Prevalencia , Autoinforme , Prueba de Paso
13.
Oxid Med Cell Longev ; 2021: 3683796, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34621463

RESUMEN

Aerobic training (AT) promotes several health benefits that may attenuate the progression of obesity associated diabetes. Since AT is an important nitric oxide (NO-) inducer mediating kidney-healthy phenotype, the present study is aimed at investigating the effects of AT on metabolic parameters, morphological, redox balance, inflammatory profile, and vasoactive peptides in the kidney of obese-diabetic Zucker rats receiving L-NAME (N(omega)-nitro-L-arginine methyl ester). Forty male Zucker rats (6 wk old) were assigned into four groups (n = 10, each): sedentary lean rats (CTL-Lean), sedentary obese rats (CTL-Obese), AT trained obese rats without blocking nitric oxide synthase (NOS) (Obese+AT), and obese-trained with NOS block (Obese+AT+L-NAME). AT groups ran 60 min in the maximal lactate steady state (MLSS), five days/wk/8 wk. Obese+AT rats improved glycemic homeostasis, SBP, aerobic capacity, renal mitochondria integrity, redox balance, inflammatory profile (e.g., TNF-α, CRP, IL-10, IL-4, and IL-17a), and molecules related to renal NO- metabolism (klotho/FGF23 axis, vasoactive peptides, renal histology, and reduced proteinuria). However, none of these positive outcomes were observed in CTL-Obese and Obese+AT+L-NAME (p < 0.0001) groups. Although Obese+AT+L-NAME lowered BP (compared with CTL-Obese; p < 0.0001), renal damage was observed after AT intervention. Furthermore, AT training under conditions of low NO- concentration increased signaling pathways associated with ACE-2/ANG1-7/MASr. We conclude that AT represents an important nonpharmacological intervention to improve kidney function in obese Zucker rats. However, these renal and metabolic benefits promoted by AT are dependent on NO- bioavailability and its underlying regulatory mechanisms.


Asunto(s)
Riñón/metabolismo , Óxido Nítrico/metabolismo , Obesidad/metabolismo , Condicionamiento Físico Animal , Transducción de Señal/efectos de los fármacos , Animales , Disponibilidad Biológica , Glucemia/metabolismo , Inhibidores Enzimáticos/farmacología , Masculino , Mitocondrias/metabolismo , Modelos Animales , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Oxidación-Reducción/efectos de los fármacos , Ratas , Ratas Zucker , Especies Reactivas de Oxígeno/metabolismo
14.
Front Endocrinol (Lausanne) ; 12: 660793, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34149616

RESUMEN

Metformin is an antidiabetic drug used for the treatment of diabetes and metabolic diseases. Imbalance in the autonomic nervous system (ANS) is associated with metabolic diseases. This study aimed to test whether metformin could improve ANS function in obese rats. Obesity was induced by neonatal treatment with monosodium L-glutamate (MSG). During 21-100 days of age, MSG-rats were treated with metformin 250 mg/kg body weight/day or saline solution. Rats were euthanized to evaluate biometric and biochemical parameters. ANS electrical activity was recorded and analyzed. Metformin normalized the hypervagal response in MSG-rats. Glucose-stimulated insulin secretion in isolated pancreatic islets increased in MSG-rats, while the cholinergic response decreased. Metformin treatment normalized the cholinergic response, which involved mostly the M3 muscarinic acetylcholine receptor (M3 mAChR) in pancreatic beta-cells. Protein expression of M3 mAChRs increased in MSG-obesity rats, while metformin treatment decreased the protein expression by 25%. In conclusion, chronic metformin treatment was effective in normalizing ANS activity and alleviating obesity in MSG-rats.


Asunto(s)
Sistema Nervioso Autónomo/efectos de los fármacos , Hipoglucemiantes/uso terapéutico , Metformina/uso terapéutico , Obesidad/tratamiento farmacológico , Acetilcolina/farmacología , Animales , Glucosa/farmacología , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Neostigmina/farmacología , Obesidad/inducido químicamente , Obesidad/metabolismo , Obesidad/fisiopatología , Ratas Wistar , Receptor Muscarínico M3/metabolismo , Glutamato de Sodio , Nervio Vago/efectos de los fármacos , Nervio Vago/fisiología
15.
Sci Rep ; 10(1): 9485, 2020 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-32528038

RESUMEN

Time-of-day dependent fluctuations in exercise performance have been documented across different sports and seem to affect both endurance and resistance modes of exercise. Most of the studies published to date have shown that the performance in short-duration maximal exercises (i.e. less than 1 min - e.g. sprints, jumps, isometric contractions) exhibits diurnal fluctuations, peaking between 16:00 and 20:00 h. However, the time-of-day effects on short duration exercise performance may be minimized by the following factors: (1) short exposures to moderately warm and humid environments; (2) active warm-up protocols; (3) intermittent fasting conditions; (4) warming-up while listening to music; or (5) prolonged periods of training at a specific time of day. This suggests that short-duration maximal exercise performance throughout the day is controlled not only by body temperature, hormone levels, motivation and mood state but also by a versatile circadian system within skeletal muscle. The time of day at which short-duration maximal exercise is conducted represents an important variable for training prescription. However, the literature available to date lacks a specific review on this subject. Therefore, the present review aims to (1) elucidate time-of-day specific effects on short-duration maximal exercise performance and (2) discuss strategies to promote better performance in short-duration maximal exercises at different times of the day.


Asunto(s)
Rendimiento Atlético/fisiología , Ejercicio Físico/fisiología , Temperatura Corporal/fisiología , Humanos , Motivación/fisiología , Músculo Esquelético/fisiología , Resistencia Física/fisiología , Factores de Tiempo
16.
Pulm Circ ; 10(2): 2045894019888422, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32523683

RESUMEN

Six-minute walk distance (6MWD) assessment is recommended for pulmonary arterial hypertension multidimensional risk stratification. However, current 6MWD cut-off values were mainly derived from North American and European pulmonary arterial hypertension registries. Therefore, it is unknown if such cut-off values broadly apply to other geographical populations. In this study, we aimed to identify 6MWD cut-off values for Brazilian pulmonary arterial hypertension patients and to contrast our findings to current international Pulmonary Hypertension guidelines recommendations. One-hundred four consecutive pulmonary arterial hypertension patients were allocated in groups according to their 6MWD, considering 50 m as a clinically relevant 6MWD difference. Next, patients were categorized into different 6MWD ranges based on similar survival rates in each group: < 250 m, 250-400 m, and >400 m. The study outcome was all-cause mortality and transplantation according to the 6MWD range. Survival was truncated at five years. Median follow-up period was 4.35 years (0.48-5.00). Survival rates at 1, 2, 3, and 5 years were 96%, 89%, 81%, and 73%, respectively. Cox analyses adjusted for age, sex, and pulmonary arterial hypertension etiology showed that 6MWD < 250 m and >400 m were associated with higher and lower risk of all-cause mortality and transplantation. According to Harrell's c-statistic, the prognostic discrimination of the 6MWD cut-off value identified by the current study was 0.70 while international Pulmonary Hypertension guidelines 6MWD cut-offs value was 0.61. In conclusion, our findings suggest that 6MWD geographical variations should be considered when assessing risk stratification in pulmonary arterial hypertension.

17.
Respir Care ; 65(7): 977-983, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31992673

RESUMEN

BACKGROUND: The BODE (body mass index, air-flow obstruction, dyspnea, exercise capacity) index is a composite prognostic marker that predicts mortality in COPD. It includes body mass index, air-flow obstruction, dyspnea score, and exercise capacity by using the 6-min walk distance. However, a 30-m-long corridor is necessary to perform the test and this limits its use in clinical practice. Step tests may elicit distinct physiologic responses compared with the 6-min walk test but are easy to perform in the office setting. We sought to investigate whether a 4-min step test would be a suitable surrogate of the 6-min walk test, in a modified BODE step index (simplified BODE index), to predict mortality in COPD. METHODS: Individuals with COPD performed a self-paced 4-min step test, and the simplified BODE index was calculated by replacing the 6-min walk distance by the number of steps climbed. Cutoff values were determined by receiver operating characteristic curve analysis as follows: score 0 for >60 steps; score 1 for 50-60 steps; score 2 for 40-49 steps; and score 3 for <40 steps. RESULTS: A total of 186 individuals with COPD were enrolled from 2011 to 2016 (60% males; mean ± SD age, 65 ± 9 y; mean ± SD FEV1, 50 ± 17 L). There were 36 deaths among the study cohort. The simplified BODE index was a prognostic marker, independent of cardiovascular comorbidities and oxygen desaturation (HR 1.12, confidence interval (CI) [1.03-1.22]). Individuals with simplified BODE index scores ≥ 7 were at higher risk of death from any cause (P < .001, log-rank test). CONCLUSIONS: This was the first study, to our knowledge, to show that the 4-min step test as a surrogate of exercise capacity in the BODE index (simplified BODE index) is an independent predictor of mortality in COPD and may help to spread its use among practicing physicians.


Asunto(s)
Índice de Masa Corporal , Tolerancia al Ejercicio , Enfermedad Pulmonar Obstructiva Crónica , Anciano , Disnea/etiología , Disnea/mortalidad , Prueba de Esfuerzo , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Índice de Severidad de la Enfermedad
18.
Sci Rep ; 10(1): 11708, 2020 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-32678132

RESUMEN

Patients in maintenance hemodialisys (HD) present sleep disorders, increased inflammation, unbalanced redox profiles, and elevated biomarkers representing endothelial dysfunction. Resistance training (RT) has shown to mitigate the loss of muscle mass, strength, improve inflammatory profiles, and endothelial function while decreasing oxidative stress for those in HD. However, the relation between those factors and sleep quality are inadequately described. The aim of this study was to verify the effects of 3 months of RT on sleep quality, redox balance, nitric oxide (NO) bioavailability, inflammation profile, and asymmetric dimethylarginine (ADMA) in patients undergoing HD. Our primary goal was to describe the role of RT on sleep quality. Our secondary goal was to evaluate the effect of RT on NO, metabolism markers, and inflammatory and redox profiles as potential mechanisms to explain RT-induced sleep quality changes. Fifty-five men undergoing maintenance hemodialysis were randomized into either a control (CTL, n = 25) and RT group (RTG; n = 30). Participants in the RT group demonstrated an improvement in sleep pattern, redox, inflammatory profiles, and biomarkers of endothelial function (NO2- and ADMA). This group also increased muscle strength (total workload in RT exercises of upper and lower limbs). These findings support that RT may improve the clinical status of HD patients by improving their sleep quality, oxidative and inflammatory parameters.


Asunto(s)
Oxidación-Reducción , Diálisis Renal , Insuficiencia Renal Crónica/terapia , Entrenamiento de Fuerza/métodos , Trastornos del Sueño-Vigilia/terapia , Sueño , Anciano , Arginina/análogos & derivados , Arginina/análisis , Arginina/metabolismo , Biomarcadores/análisis , Biomarcadores/metabolismo , Endotelio/metabolismo , Humanos , Inflamación/metabolismo , Masculino , Persona de Mediana Edad , Fuerza Muscular , Óxido Nítrico/análisis , Óxido Nítrico/metabolismo , Estrés Oxidativo , Resultado del Tratamiento
19.
Metabolism ; 85: 250-258, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29751019

RESUMEN

OBJECTIVE: The exposure to artificial light at night (ALAN) disrupts the biological rhythms and has been associated with the development of metabolic syndrome. MicroRNAs (miRNAs) display a critical role in fine-tuning the circadian system and energy metabolism. In this study, we aimed to assess whether altered miRNAs expression in the liver underlies metabolic disorders caused by disrupted biological rhythms. RESULTS: We found that C3H/HePas mice exposed to ALAN developed obesity, and hepatic steatosis, which was paralleled by decreased expression of Rev-erbα and up-regulation of its lipogenic targets ACL and FAS in liver. Furthermore, the expression of Rev-erbα-targeting miRNAs, miR-140-5p, 185-5p, 326-5p and 328-5p were increased in this group. Consistently, overexpression of these miRNAs in primary hepatocytes reduced Rev-erbα expression at the mRNA and protein levels. Importantly, overexpression of Rev-erbα-targeting miRNAs increased mRNA levels of Acly and Fasn. CONCLUSION: Thus, altered miRNAs profile is an important mechanism underlying the disruption of the peripheral clock caused by exposure to ALAN, which could lead to hepatic steatosis.


Asunto(s)
Ritmo Circadiano/fisiología , Hígado Graso/metabolismo , Luz , Hígado/metabolismo , MicroARNs/metabolismo , Animales , Glucemia/metabolismo , Metabolismo Energético/fisiología , Lipogénesis/fisiología , Masculino , Ratones , MicroARNs/genética , Actividad Motora/fisiología
20.
PLoS One ; 13(9): e0204072, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30260970

RESUMEN

Determination of potentially-reversible factors contributing to exertional dyspnea remains an unmet clinical need in chronic thromboembolic pulmonary hypertension (CTEPH). Therefore, we aimed to evaluate the influence of inspiratory muscle weakness (IMW) on exercise capacity and dyspnea during effort in patients with CTEPH. We performed a prospective cross-sectional study that included thirty-nine consecutive patients with CTEPH (48 ± 15 yrs, 61% female) confirmed by right heart catheterization that underwent an incremental cardiopulmonary exercise test, 6-minute walk test and maximum inspiratory pressure (MIP) measurement. MIP < 70%pred was found in 46% of patients. On a multiple linear regression analysis, MIP was independently associated with 6MWD and [Formula: see text]. Patients with MIP < 70% presented greater [Formula: see text] than those with MIP ≥ 70%. Additionally, they also presented stronger sensations of dyspnea throughout exercise, even when adjusted for ventilation. At rest and at different levels of exercise, mean inspiratory flow (VT/TI) was significantly higher in patients with MIP < 70%. In conclusion, IMW is associated with a rapid increase of dyspnea, higher inspiratory load and poor exercise capacity in patients with CTEPH.


Asunto(s)
Disnea/etiología , Disnea/fisiopatología , Hipertensión Pulmonar/complicaciones , Hipertensión Pulmonar/fisiopatología , Inhalación/fisiología , Debilidad Muscular/complicaciones , Debilidad Muscular/fisiopatología , Tromboembolia/fisiopatología , Enfermedad Crónica , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tromboembolia/complicaciones , Prueba de Paso
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