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1.
Int J Sport Nutr Exerc Metab ; 33(5): 255-264, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37414400

RESUMO

Neck adipose tissue (NAT) accumulation and neck circumference are independent predictors of cardiometabolic risk (CMR) and low-grade chronic inflammation in young adults. The present study examines whether a 24-week concurrent exercise intervention can reduce NAT volume and neck circumference in young adults, and whether any changes in these variables are related to changes in body composition, CMR, and the inflammatory profile. Seventy-four participants (51 women, age 22 ± 2 years) were included in the main analyses, after being randomly assigned to either a (a) control (n = 34), (b) moderate-intensity exercise (n = 19), or (c) vigorous-intensity exercise (n = 21) group. Participants in the exercise groups trained 3-4 days/week (endurance + resistance exercise training). NAT volume and NAT distribution across different depots were estimated using computed tomography before and after the intervention. Anthropometric variables, body composition (determined by dual-energy X-ray absorptiometry), and CMR/inflammatory markers were also recorded. The exercise intervention did not reduce the total NAT volume, nor was NAT distribution affected (p > .05). However, it did reduce neck circumference in the vigorous-intensity exercise group compared with the moderate-intensity exercise and control groups (by 0.8 and 1 cm, respectively, p ≤ .05). Changes in total NAT and neck circumference were positively, albeit weakly, related (adj. R2: .05-.21, all p ≤ .05) to changes in body weight and adiposity, leptin (only total NAT), and CMR (only neck circumference). Altogether 24 weeks of concurrent exercise does not appear to reduce NAT accumulation in young adults, but may slightly reduce neck circumference in those who partake in vigorous exercise.


Assuntos
Adiposidade , Obesidade , Humanos , Feminino , Adulto Jovem , Adulto , Peso Corporal , Exercício Físico , Terapia por Exercício/métodos
2.
Int J Obes (Lond) ; 45(4): 733-745, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33139886

RESUMO

OBJECTIVES: Neck adipose tissue (NAT) volume increases with general adiposity, with fat accumulating in different neck tissue compartments. In patients with certain malignant/benign tumours, the accumulation of NAT, and certain NAT distributions, have been associated with cardiometabolic risk (CMR). However, it is unknown whether the same relationships exist in healthy people, and whether NAT accumulation and distribution are related to the inflammatory status. METHODS: In this cross-sectional study, 139 young healthy adults (68% women) underwent a computed tomography scan to quantify the volume of compartmental (i.e., subcutaneous, intermuscular and perivertebral) and total NAT at the height of vertebra C5. Anthropometric indicators were measured, and body composition determined using dual energy X-ray absorptiometry. Information on CMR factors (i.e., blood glycaemic and lipid markers, blood pressure and physical fitness) was also gathered, and a CMR score calculated. Several plasma cytokines and serum components of the innate immune system were measured to determine the inflammatory status. RESULTS: Compartmental and total NAT volumes were directly related to body mass index (BMI), and lean, fat, and visceral adipose tissue (VAT) masses (all, P ≤ 0.05). Larger compartmental (especially intermuscular) and total NAT volumes were directly associated with the CMR score, several CMR factors (i.e., glycaemic and lipid markers and blood pressure), and the C3, C4 and leptin concentrations. They were, however, inversely correlated with the CMR factors high density lipoprotein-cholesterol (HDL-C) and physical fitness, and with the adiponectin concentration (all P ≤ 0.05). Several of these associations remained statistically significant (P ≤ 0.05) after adjustment for BMI, body fat percentage or VAT mass. Overall, results did not change after applying false discovery rate correction. CONCLUSIONS: NAT volume and its distribution among different tissue compartments is associated with the CMR and inflammatory profile of young healthy adults. Total NAT volume appears to be as valuable as VAT mass in terms of predicting CMR and inflammatory status.


Assuntos
Adiposidade , Fatores de Risco de Doenças Cardíacas , Obesidade Abdominal/diagnóstico , Absorciometria de Fóton , Tecido Adiposo , Adolescente , Adulto , Composição Corporal , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Inflamação , Masculino , Pescoço/anatomia & histologia , Adulto Jovem
3.
Cardiovasc Diabetol ; 20(1): 151, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315463

RESUMO

BACKGROUND: Succinate is produced by both host and microbiota, with a key role in the interplay of immunity and metabolism and an emerging role as a biomarker for inflammatory and metabolic disorders in middle-aged adults. The relationship between plasma succinate levels and cardiovascular disease (CVD) risk in young adults is unknown. METHODS: Cross-sectional study in 100 (65% women) individuals aged 18-25 years from the ACTIvating Brown Adipose Tissue through Exercise (ACTIBATE) study cohort. CVD risk factors, body composition, dietary intake, basal metabolic rate, and cardiorespiratory fitness were assessed by routine methods. Plasma succinate was measured with an enzyme-based assay. Brown adipose tissue (BAT) was evaluated by positron emission tomography, and circulating oxylipins were assessed by targeted metabolomics. Fecal microbiota composition was analyzed in a sub-sample. RESULTS: Individuals with higher succinate levels had higher levels of visceral adipose tissue (VAT) mass (+ 42.5%), triglycerides (+ 63.9%), C-reactive protein (+ 124.2%), diastolic blood pressure (+ 5.5%), and pro-inflammatory omega-6 oxylipins than individuals with lower succinate levels. Succinate levels were also higher in metabolically unhealthy individuals than in healthy overweight/obese peers. Succinate levels were not associated with BAT volume or activity or with fecal microbiota composition and diversity. CONCLUSIONS: Plasma succinate levels are linked to a specific pro-inflammatory omega-6 signature pattern and higher VAT levels, and seem to reflect the cardiovascular status of young adults.


Assuntos
Doenças Cardiovasculares/sangue , Ácido Succínico/sangue , Adiposidade , Adolescente , Adulto , Fatores Etários , Biomarcadores/sangue , Pressão Sanguínea , Proteína C-Reativa/análise , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia , Estudos Transversais , Feminino , Microbioma Gastrointestinal , Fatores de Risco de Doenças Cardíacas , Humanos , Mediadores da Inflamação/sangue , Gordura Intra-Abdominal/fisiopatologia , Masculino , Oxilipinas/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Triglicerídeos/sangue , Regulação para Cima , Adulto Jovem
4.
Int J Sport Nutr Exerc Metab ; 31(3): 250-258, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33668020

RESUMO

The role of lifestyle behaviors on neck adipose tissue (NAT), a fat depot that appears to be involved in the pathogenesis of different cardiometabolic diseases and in inflammatory status, is unknown. In this cross-sectional and exploratory study, the authors examined the relationship between sedentary time and physical activity (PA) with neck adiposity in young adults. A total of 134 subjects (69% women, 23 ± 2 years) were enrolled. The time spent in sedentary behavior and PA of different intensity were objectively measured for 7 consecutive days (24 hr/day), using a wrist (nondominant)-worn accelerometer. The NAT volume was assessed using computed tomography, and the compartmental (subcutaneous, intermuscular, and perivertebral) and total NAT volumes were determined at the level of vertebra C5. Anthropometric indicators and body composition (by dual-energy X-ray absorptiometry) were determined. The time spent in light physical activity and moderate physical activity (MPA) and the overall PA were inversely associated with the intermuscular NAT volume in men, as were the MPA and overall PA with total NAT volume (all ps ≤ .04). Sedentary time was directly related to the total NAT volume (p = .04). An opposite trend was observed in women, finding a direct relationship of MPA with the subcutaneous NAT; of light physical activity, MPA, and overall PA with the perivertebral NAT; and of light physical activity with total NAT volumes (all ps ≤ .05). The observed associations were weak, and after adjusting for multiplicity, the results became nonsignificant (p > .05). These findings suggest that the specific characteristics of PA (time and intensity) might have sex-dependent implications in the accumulation of NAT.


Assuntos
Adiposidade , Exercício Físico/fisiologia , Comportamento Sedentário , Fatores Sexuais , Absorciometria de Fóton , Acelerometria , Adulto , Composição Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Pescoço/anatomia & histologia , Fatores de Tempo , Dispositivos Eletrônicos Vestíveis , Adulto Jovem
5.
Int J Obes (Lond) ; 43(8): 1516-1525, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30518823

RESUMO

BACKGROUND: Brown adipose tissue (BAT) seems to play a role in bone morphogenesis. A negative association has been reported between BAT and bone mineral density (BMD) in women, but not in men. A panel of experts has recently published a set of recommendations for BAT assessment, and thus, to re-address previously reported associations is needed. This study aimed to investigate the association between cold-induced BAT 18F-Fluorodeoxyglucose (18F-FDG) uptake and BMD in young healthy adults. METHODS: Ninety-eight healthy adults (68 women; 22 ± 2.2 years old; 24.3 ± 4.5 kg/m2) cold-induced BAT was assessed by means of an 18F-FDG positron emission tomography-computed tomography (PET-CT) scan preceded by a personalized cold stimulation. The cold exposure consisted in 2 h in a mild cold room at 19.5-20 °C wearing a water perfused cooling vest set 4 °C above the individual shivering threshold. Total body and lumbar spine BMD were assessed by a whole-body DXA scan. RESULTS: We found no association between BMD and cold-induced BAT volume, mean, and maximal activity (all P > 0.1) in neither young and healthy men nor women. These results remained unchanged when adjusting by height, by body composition, and by objectively assessed physical activity. Sensitivity analyses using the criteria to quantify cold-induced BAT-related parameters applied in previous studies did not change the results. CONCLUSIONS: In summary, our study shows that there is no association between cold-induced BAT and BMD in young healthy adults. Moreover, our data support the notion that previously shown associations between BAT and BMD in healthy non-calorically restricted individuals, could be driven by methodological issues related to BAT assessment and/or sample size limitations.


Assuntos
Tecido Adiposo Marrom/fisiologia , Densidade Óssea/fisiologia , Temperatura Baixa , Absorciometria de Fóton , Tecido Adiposo Marrom/diagnóstico por imagem , Adolescente , Adulto , Composição Corporal/fisiologia , Exercício Físico/fisiologia , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiologia , Imagem Corporal Total , Adulto Jovem
6.
Exp Physiol ; 104(2): 168-173, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30468689

RESUMO

NEW FINDINGS: What is the central question of this study? In some studies, biopsies have been performed of the subcutaneous adipose tissue in the abdomen, and they failed to find browning markers. Is the abdomen the right place to take biopsies? What is the main finding and its importance? For first time, we observed that the glucose uptake in the dorsocervical subcutaneous adipose tissue is higher in comparison to other areas of subcutaneous adipose tissue. ABSTRACT: Neonates have subcutaneous brown adipose tissue (BAT) in the dorsocervical area, and it is thought that these depots gradually disappear with age. Here, we determined that young adults have high 18 F-flurodeoxyglucose (18 F-FDG) uptake in the subcutaneous adipose tissue (SAT) of the dorsocervical area. A total of 133 young adults (age 22 ± 2 years; body mass index 25 ± 5 kg m2 ) were included in the study. We performed a shivering threshold test for every participant. Later, we performed 2 h of personalized cold exposure, immediately before a positron emission tomography/computed tomography scan. We showed that 23 of 133 participants had 18 F-FDG uptake in the dorsocervical area that achieved the criteria to be considered BAT, mainly in women (96%, n = 22 of 23). In the whole sample, the glucose uptake in the SAT of the dorsocervical area was positively correlated with BAT volume and activity located in the supraclavicular area. We showed that the 18 F-FDG uptake of the SAT of the dorsocervical area in humans is different from that of other SAT areas. Future studies are warranted to confirm the brown signature of this tissue.


Assuntos
Fluordesoxiglucose F18/metabolismo , Gordura Subcutânea/metabolismo , Adulto , Transporte Biológico/fisiologia , Índice de Massa Corporal , Feminino , Humanos , Masculino , Tomografia por Emissão de Pósitrons/métodos , Adulto Jovem
7.
J Therm Biol ; 82: 178-185, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31128645

RESUMO

Currently, 18 [F]-Fluorodeoxyglucose (18F-FDG) in combination with a positron emission tomography/computed tomography (PET/CT) scan analysis is the most commonly used method to quantify human BAT volume and activity. However, this technique presents several drawbacks which negatively affect participant's health. The aim of the present work is to determine whether supraclavicular skin temperature can be used as an indirect marker of cold-induced BAT and skeletal muscle 18F-FDG uptake in adults, while taking into account body composition. We performed a personalized cooling protocol just before an 18F-FDG-PET/CT scan, and we measured supraclavicular skin temperature before (in warm conditions) and after the cooling protocol in 88 adults (n = 57 women, mean age: 21.9 ±â€¯2.1 years old, body mass index: 24.5 ±â€¯4.3 km/m2). We found that supraclavicular skin temperature at the warm and cold periods was weakly and positively associated with BAT activity (SUVmean and SUVpeak: ß = 3.000; R2 = 0.072; P = 0.022 and ß = 2.448; R2 = 0.060; P = 0.021), but not with skeletal muscle 18F-FDG uptake, after controlling for body composition. We performed further analyses and the positive associations persisted only in the group of women. In conclusion, supraclavicular skin temperature in warm and cold conditions seems to be related with cold-induced 18F-FDG uptake by BAT only in women, although the low explained variance of these associations means that there are other factors involved in the supraclavicular skin temperature.


Assuntos
Tecido Adiposo Marrom/metabolismo , Fluordesoxiglucose F18/metabolismo , Temperatura Cutânea , Adulto , Composição Corporal , Temperatura Baixa , Feminino , Humanos , Masculino , Músculo Esquelético/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto Jovem
8.
J Therm Biol ; 82: 186-196, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31128647

RESUMO

Brown adipose tissue (BAT) thermogenic activity is commonly assessed with a positron emission tomography with computed tomography scan (PET/CT). This technique has several limitations and alternative techniques are needed. Supraclavicular skin temperature measured with iButtons and infrared thermography (IRT) has been proposed as an indirect marker of BAT activity. We studied the concurrent validity of skin temperature measured with iButtons vs. IRT and the association of supraclavicular skin temperature measured with iButtons and IRT with BAT. We measured skin temperature upon a shivering threshold test with iButtons and IRT in 6 different regions in 12 participants (n = 2 men). On a separate day, we determined supraclavicular skin temperature with an iButton and IRT after 2 h of a personalized cooling protocol. Thereafter, we quantified BAT volume and activity by PET/CT. We observed that the absolute differences between the devices were statistically different from 0 (all P < 0.05) after the shivering threshold test. Moreover, we did not find any association between supraclavicular skin temperature measured with iButtons or IRT and BAT 18F-FDG activity (r = -0.213; P = 0.530 and r = -0.079; P = 0.817). However, we observed a negative association of supraclavicular skin temperature measured by IRT with BAT 18F-FDG volume (r = -0.764; P = 0.006), but not with supraclavicular skin temperature measured with iButtons (r = -0.546; P = 0.082). In light of these results, we concluded that the measurement of skin temperature obtained by iButtons and IRT are not comparable. Furthermore, it seems that supraclavicular skin temperature is not associated with BAT 18F-FDG activity, but it appears to be negatively associated with BAT 18F-FDG volume in the case of IRT.


Assuntos
Tecido Adiposo Marrom/fisiologia , Temperatura Cutânea , Termogênese , Termografia/métodos , Adolescente , Adulto , Feminino , Fluordesoxiglucose F18/metabolismo , Humanos , Raios Infravermelhos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto Jovem
9.
Am J Physiol Regul Integr Comp Physiol ; 315(6): R1281-R1288, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30365352

RESUMO

Brown adipose tissue (BAT) activity is influenced by the outdoor temperature variation. However, people spend most of their time indoors, especially in colder regions and during cold seasons. Therefore, outdoor temperature is probably not an accurate tool to quantify the exposure of the participants before BAT quantification. We studied the association of wrist and personal environmental temperatures with cold-induced BAT and skeletal muscle [18F]fluorodeoxyglucose ([18F]FDG) uptake in adults. A total of 74 participants wore two iButtons during 7 days to measure wrist temperature (WT) and personal level of environmental temperature (Personal-ET). Thereafter, we performed a 2-h personalized cooling protocol before performing an [18F]FDG-PET/CT scan. WT was negatively associated with BAT volume ( R2 = 0.122; P = 0.002) and BAT activity [standardized uptake value (SUV)peak, R2 = 0.083; P = 0.012]. Moreover, Personal-ET was negatively associated with BAT volume ( R2 = 0.164; P < 0.001), BAT activity (SUVmean and SUVpeak, all R2 ≥ 0.167; P < 0.001), and skeletal muscle activity (SUVpeak, R2 = 0.122; P = 0.002). Interestingly, the time exposed to a certain Personal-ET (16-20°C) positively correlated only with [18F]FDG uptake by BAT (volume and activity; all P ≤ 0.05), whereas the time exposed to 12-15°C positively correlated only with measures of [18F]FDG uptake by skeletal muscle activity (all P ≤ 0.05). This study shows that WT and Personal-ET are associated with [18F]FDG uptake by BAT and skeletal muscle activity in adults within certain temperature thresholds. Moreover, our results suggest that [18F]FDG uptake by human BAT or skeletal muscle can be activated or inhibited in different ranges of ambient temperatures exposures. Results should be taken with caution because the observed associations were relatively weak.


Assuntos
Tecido Adiposo Marrom/irrigação sanguínea , Temperatura Baixa , Fluordesoxiglucose F18/metabolismo , Músculo Esquelético/metabolismo , Punho/irrigação sanguínea , Tecido Adiposo Marrom/metabolismo , Adolescente , Adulto , Transporte Biológico/fisiologia , Índice de Massa Corporal , Feminino , Humanos , Masculino , Músculo Esquelético/irrigação sanguínea , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Temperatura , Adulto Jovem
10.
Int J Mol Sci ; 18(7)2017 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-28661441

RESUMO

The role of dietary fat unsaturation and the supplementation of coenzyme Q have been evaluated in relation to bone health. Male Wistar rats were maintained for 6 or 24 months on two diets varying in the fat source, namely virgin olive oil, rich in monounsaturated fatty acids, or sunflower oil, rich in n-6 polyunsaturated fatty acids. Both dietary fats were supplemented or not with coenzyme Q10 (CoQ10). Bone mineral density (BMD) was evaluated in the femur. Serum levels of osteocalcin, osteopontin, receptor activator of nuclear factor κB ligand (RANKL), osteoprotegerin (OPG), adrenocorticotropin (ACTH) and parathyroid hormone (PTH), as well as urinary F2-isoprostanes were measured. Aged animals fed on virgin olive oil showed higher BMD than those fed on sunflower oil. In addition, CoQ10 prevented the age-related decline in BMD in animals fed on sunflower oil. Urinary F2-isoprostanes analysis showed that sunflower oil led to the highest oxidative status in old animals, which was avoided by supplementation with CoQ10. In conclusion, lifelong feeding on virgin olive oil or the supplementation of sunflower oil on CoQ10 prevented, at least in part mediated by a low oxidative stress status, the age-related decrease in BMD found in sunflower oil fed animals.


Assuntos
Densidade Óssea/efeitos dos fármacos , Gorduras Insaturadas na Dieta/administração & dosagem , Suplementos Nutricionais , Azeite de Oliva/administração & dosagem , Óleo de Girassol/administração & dosagem , Ubiquinona/análogos & derivados , Hormônio Adrenocorticotrópico/sangue , Animais , F2-Isoprostanos/urina , Ácidos Graxos Monoinsaturados/sangue , Ácidos Graxos Insaturados/sangue , Masculino , Osteocalcina/sangue , Osteopontina/sangue , Osteoprotegerina/sangue , Estresse Oxidativo/efeitos dos fármacos , Hormônio Paratireóideo/sangue , Ligante RANK/sangue , Ratos , Ratos Wistar , Ubiquinona/administração & dosagem , Ubiquinona/sangue
11.
Eur J Nucl Med Mol Imaging ; 42(6): 886-95, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25673054

RESUMO

PURPOSE: The follow-up of treated low-grade glioma (LGG) requires the evaluation of subtle clinical changes and MRI results. When the result is inconclusive, additional procedures are required to assist decision-making, such as the use of advanced MRI (aMRI) sequences and nuclear medicine scans (SPECT and PET). The aim of this study was to determine whether incorporating (18)F-fluorocholine PET/CT in the follow-up protocol for treated LGG improves diagnostic accuracy and clinical utility. METHODS: This was a prospective case-series study in patients with treated LGG during standard follow-up with indeterminate clinical and/or radiological findings of tumour activity. All patients underwent clinical evaluation, aMRI, (201)Tl-SPECT and (18)F-fluorocholine PET/CT. Images were interpreted by visual evaluation complemented with semiquantitative analysis. RESULTS: Between January 2012 and December 2013, 18 patients were included in this study. The final diagnosis was established by histology (five surgical specimens, one biopsy specimen) or by consensus of the Neuro-Oncology Group (11 patients) after a follow-up of >6 months (mean 14.9 ± 2.72 months). The global diagnostic accuracies were 90.9% for aMRI (38.8% inconclusive), 69.2 % for (201)Tl-SPECT (11.1% inconclusive), and 100% for (18)F-fluorocholine PET/CT. (201)Tl-SPECT led correctly to a change in the initial approach in 38.9% of patients but might have led to error in 27.8%. The use of (18)F-fluorocholine PET/CT alone rather than (201)Tl-SPECT led correctly to a change in the approach suggested by routine follow-up in 72.2% of patients and endorsed the approach in the remaining 27.8%. CONCLUSION: Our results support the need to complement structural MRI with aMRI and nuclear medicine procedures in selected patients. (18)F-Fluorocholine PET/CT can be useful in the individualized management of patients with treated LGG with uncertain clinical and/or radiological evidence of tumour activity.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Colina/análogos & derivados , Glioma/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Tálio , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
12.
Eur J Sport Sci ; 23(4): 625-636, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35152857

RESUMO

ABSTRACTIn rodents, exercise alters the plasma concentration of exerkines that regulate white adipose tissue (WAT) browning or brown adipose tissue (BAT) metabolism. This study aims to analyse the acute and chronic effect of exercise on the circulating concentrations of 16 of these exerkines in humans. Ten young sedentary adults (6 female) performed a maximum walking effort test and a resistance exercise session. The plasma concentration of 16 exerkines was assessed before, and 3, 30, 60, and 120 min after exercise. Those exerkines modified by exercise were additionally measured in another 28 subjects (22 women). We also measured the plasma concentrations of the exerkines before and after a 24-week exercise programme (endurance + resistance; 3-groups: control, moderate-intensity and vigorous-intensity) in 110 subjects (75 women). Endurance exercise acutely increased the plasma concentration of lactate, norepinephrine, brain-derived neurotrophic factor, interleukin 6, and follistatin-like protein 1 (3 min after exercise), and musclin and fibroblast growth factor 21 (30 and 60 min after exercise), decreasing the plasma concentration of leptin (30 min after exercise). Adiponectin, atrial natriuretic peptide (ANP), ß-aminoisobutyric acid, meteorin-like, follistatin, pro-ANP, irisin and myostatin were not modified or not detectable. The resistance exercise session increased the plasma concentration of lactate 3 min after exercise. Chronic exercise did not alter the plasma concentration of these exerkines. In sedentary young adults, acute endurance exercise releases to the bloodstream exerkines that regulate BAT metabolism and WAT browning. In contrast, neither a low-volume resistance exercise session nor a 24-week training programme modified plasma levels of these molecules.HighlightsAcute endurance exercise increases the plasma concentration of lactate, norepinephrine, brain-derived neurotrophic factor, interleukin 6, follistatin-like protein 1, musclin, and fibroblast growth factor 21, and decrease the plasma concentration of leptin.The exercise-induced change in lactate plasma concentration is positively associated with brown adipose tissue volume, glucose uptake and radiodensity.Neither acute resistance exercise nor chronic exercise significantly alter the plasma concentration of these exerkines.Trial registration: ClinicalTrials.gov identifier: NCT02365129.


Assuntos
Proteínas Relacionadas à Folistatina , Leptina , Adulto Jovem , Humanos , Feminino , Fator Neurotrófico Derivado do Encéfalo , Tecido Adiposo Marrom/metabolismo , Interleucina-6 , Proteínas Relacionadas à Folistatina/metabolismo , Lactatos/metabolismo
13.
Ann Surg ; 255(5): 986-92, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22504197

RESUMO

OBJECTIVES: To evaluate prospectively the usefulness of the routine determination of BRAF(T1799A) mutation on thyroid fine-needle aspiration biopsy (FNAB) to detect cytopathology false negative papillary thyroid carcinomas (PTC) and, therefore, as a tool to improve the sensitivity of the preoperative cytopathological diagnosis of PTC in thyroid nodules. BACKGROUND: FNAB is the most reliable diagnostic test to discriminate between malignant and benign thyroid nodules, but nondiagnostic results remain a clinical management dilemma. BRAF(T1799A) mutation is the most prevalent genetic alteration in thyroid cancers and is specific for PTC, characteristics that make it the most potentially helpful genetic tool to improve the diagnostic accuracy of FNAB. METHODS: An exhaustive recruitment of all patients subjected to thyroid FNAB in our institution during 4 years was performed. BRAF(T1799A) mutation was determined on thyroid FNAB specimens by PCR and restriction fragment length polymorphism, plus direct sequencing in positive samples. RESULTS: BRAF(T1799A) mutation on FNAB detected 47.2% (17/36) of PTC cases. It confirmed preoperatively 45.5% (5/11) of the PTC cases in the indeterminate category and decreased the rate of cytopathology false-negatives in 33.3% (6/18), improving the combined (BRAF(T1799A) mutation + cytopathological analysis) sensitivity of the detection of PTC on FNAB in 16.7%. CONCLUSIONS: BRAF(T1799A) mutation improves the diagnosis of PTC on FNAB, mainly because of the detection of cytopathology false-negatives, and it can be helpful in the routine analysis of thyroid nodules, especially in clinical settings with moderate sensitivity to detect PTC on FNAB.


Assuntos
Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , DNA de Neoplasias/análise , DNA de Neoplasias/isolamento & purificação , Reações Falso-Negativas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto Jovem
14.
Eur J Endocrinol ; 187(1): 171-183, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36149276

RESUMO

Objectives: Brown adipose tissue (BAT) is important in the maintenance of cardiometabolic health in rodents. Recent reports appear to suggest the same in humans, although if this is true remains elusive partly because of the methodological bias that affected previous research. This cross-sectional work reports the relationships of cold-induced BAT volume, activity (peak standardized uptake, SUVpeak), and mean radiodensity (an inverse proxy of the triacylglycerols content) with the cardiometabolic and inflammatory profile of 131 young adults, and how these relationships are influenced by sex and body weight. Design: This is a cross-sectional study. Methods: Subjects underwent personalized cold exposure for 2 h to activate BAT, followed by static 18F-fluorodeoxyglucose PET-CT scanning to determine BAT variables. Information on cardiometabolic risk (CMR) and inflammatory markers was gathered, and a CMR score and fatty liver index (FLI) were calculated. Results: In men, BAT volume was positively related to homocysteine and liver damage markers concentrations (independently of BMI and seasonality) and the FLI (all P ≤ 0.05). In men, BAT mean radiodensity was negatively related to the glucose and insulin concentrations, alanine aminotransferase activity, insulin resistance, total cholesterol/HDL-C, LDL-C/HDL-C, the CMR score, and the FLI (all P ≤ 0.02). In women, it was only negatively related to the FLI (P < 0.001). These associations were driven by the results for the overweight and obese subjects. No relationship was seen between BAT and inflammatory markers (P > 0.05). Conclusions: A larger BAT volume and a lower BAT mean radiodensity are related to a higher CMR, especially in young men, which may support that BAT acts as a compensatory organ in states of metabolic disruption.


Assuntos
Doenças Cardiovasculares , Insulinas , Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Marrom/metabolismo , Alanina Transaminase , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , LDL-Colesterol , Temperatura Baixa , Estudos Transversais , Feminino , Fluordesoxiglucose F18 , Glucose/metabolismo , Homocisteína/metabolismo , Humanos , Insulinas/metabolismo , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Triglicerídeos/metabolismo , Adulto Jovem
15.
J Physiol Biochem ; 78(3): 629-640, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35381950

RESUMO

Thyroid dysfunction is associated with classic cardiometabolic risk factors in humans. However, this relationship remains unclear in young euthyroid adults. The present work examines the associations of circulating thyroid hormones (THs) and thyroid-stimulating hormone (TSH) concentrations with body composition and cardiometabolic risk factors in young euthyroid adults. A total of 106 sedentary, euthyroid adults (72 women; 22 ± 2 years old) participated in this cross-sectional study. THs and TSH serum concentrations were determined in fasting conditions (6 h). Body composition (fat mass (FM), lean mass (LM), and visceral adipose tissue (VAT)) was determined by dual-energy X-ray absorptiometry, anthropometric parameters (weight, height, and waist circumference) were measured, and neck adipose tissue mass was quantified through computed tomography (CT) scanning. Cardiometabolic risk factors including fasting glucose and lipid metabolism markers, hepatic phosphatase and transaminases, and blood pressure were also assessed. Free triiodothyronine (FT3) concentration was positively associated with body mass index, LM, VAT, and waist circumference (all P ≤ 0.038). FT3 was also associated with glucose, insulin, HOMA-IR, fatty liver index, and blood pressure (all P < 0.024). All the associations were attenuated when adjusting for sex. In contrast, we found no associations of TSH or free thyroxine with any body composition parameter or cardiometabolic risk factors. In conclusion, FT3 is associated with central adiposity and cardiometabolic risk factors including insulin resistance, fatty liver index, and mean, systolic and diastolic blood pressure in young euthyroid adults. ClinicalTrials.gov identifier: NCT02365129.


Assuntos
Fígado Gorduroso , Tri-Iodotironina , Adiposidade , Índice de Massa Corporal , Fatores de Risco Cardiometabólico , Estudos Transversais , Feminino , Glucose , Humanos , Masculino , Obesidade , Obesidade Abdominal , Fatores de Risco , Hormônios Tireóideos , Tireotropina , Tiroxina , Adulto Jovem
16.
EBioMedicine ; 85: 104313, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36374769

RESUMO

BACKGROUND: Fatty acid-derived lipid mediators including oxylipins, endocannabinoids (eCBs), and their analogues, have emerged as key metabolites in the inflammatory and immune response to physiological stressors. METHODS: This report was based on a sub-study and secondary analyses the ACTIBATE single-center unblinded randomized controlled trial (ClinicalTrials.gov ID: NCT02365129). The study was performed in the Sport and Health University Research Institute and the Virgen de las Nieves University Hospital of the University of Granada. Eligible participants were young, sedentary adults with no chronic diseases. Here, we performed both an acute endurance and resistance exercise sub-studies (n.ß=.ß14 and 17 respectively), and a 24-week supervised exercise intervention, combining endurance and resistance exercise training at moderate-intensity (MOD-EX) or vigorous-intensity (VIG-EX) exercise groups, in young sedentary adults. Randomization was performed by unrestricted randomization. Plasma levels of oxylipins, eCBs, and their analogues were measured using liquid chromatography-tandem mass spectrometry. FINDINGS: Both endurance and resistance exercise increased by.ß+50% the plasma levels of dihomo-..-linolenic acid and arachidonic acid (AA) omega-6 derived oxylipins, as well as eicosapentaenoic acid and docosahexaenoic acid omega-3 derived after 3 and 120.ßmin of the bout of exercise (all ..2.ß....ß0.219 and P.ß..±.ß0.039). These exercise modalities also increased the levels of anandamide and eCBs analogues (+25%). 145 young sedentary adults were assigned to a control (CON, n.ß=.ß54), a MOD-EX (n.ß=.ß48) or a VIG-EX (n.ß=.ß43). 102 participants were included in the final long-term analyses (CON, n.ß=.ß36; MOD-EX, n.ß=.ß33; and VIG-EX, n.ß=.ß33) of the trial. After 24-week of supervised exercise, MOD-EX decreased plasma levels of omega-6 oxylipins, concretely linoleic acid (LA) and adrenic acid derived oxylipins, and the eCBs analogues OEA and LEA in comparison to the CON (all P.ß..±.ß0.021). VIG-EX decreased LA-derived oxylipins and LEA compared to CON. No relevant adverse events were recorded. INTERPRETATION: Endurance and resistance exercises acutely increased plasma levels of oxylipins, eCBs, and their analogues, whereas 24 weeks of exercise training decreased fasting plasma levels of omega-6 oxylipins, and eCBs analogues in young, sedentary adults. FUNDING: See Acknowledgments section.


Assuntos
Endocanabinoides , Oxilipinas , Humanos , Adulto , Oxilipinas/metabolismo , Ácido Eicosapentaenoico , Ácidos Docosa-Hexaenoicos , Exercício Físico
17.
Nat Commun ; 13(1): 5259, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097264

RESUMO

Exercise modulates both brown adipose tissue (BAT) metabolism and white adipose tissue (WAT) browning in murine models. Whether this is true in humans, however, has remained unknown. An unblinded randomized controlled trial (ClinicalTrials.gov ID: NCT02365129) was therefore conducted to study the effects of a 24-week supervised exercise intervention, combining endurance and resistance training, on BAT volume and activity (primary outcome). The study was carried out in the Sport and Health University Research Institute and the Virgen de las Nieves University Hospital of the University of Granada (Spain). One hundred and forty-five young sedentary adults were assigned to either (i) a control group (no exercise, n = 54), (ii) a moderate intensity exercise group (MOD-EX, n = 48), or (iii) a vigorous intensity exercise group (VIG-EX n = 43) by unrestricted randomization. No relevant adverse events were recorded. 97 participants (34 men, 63 women) were included in the final analysis (Control; n = 35, MOD-EX; n = 31, and VIG-EX; n = 31). We observed no changes in BAT volume (Δ Control: -22.2 ± 52.6 ml; Δ MOD-EX: -15.5 ± 62.1 ml, Δ VIG-EX: -6.8 ± 66.4 ml; P = 0.771) or 18F-fluorodeoxyglucose uptake (SUVpeak Δ Control: -2.6 ± 3.1 ml; Δ MOD-EX: -1.2 ± 4.8, Δ VIG-EX: -2.2 ± 5.1; p = 0.476) in either the control or the exercise groups. Thus, we did not find any evidence of an exercise-induced change on BAT volume or activity in young sedentary adults.


Assuntos
Tecido Adiposo Marrom , Fluordesoxiglucose F18 , Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Marrom/metabolismo , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Espanha
18.
Clin Nutr ; 40(10): 5311-5321, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34536639

RESUMO

BACKGROUND: Harnessing cold-induced thermogenesis (CIT) and brown adipose tissue (BAT) activity has been proposed as a means of counteracting a positive energy balance, and thus of combating obesity and its related comorbidities. However, it has remained unclear whether CIT and BAT activity show diurnal variation in humans - knowledge that might allow treatments based on these factors to be time-optimized. METHODS: A randomized crossover experiment was designed to examine whether CIT shows morning/evening variation in young, healthy adults (n = 14, 5 women). On the first experimental day, subjects' shivering thresholds were determined following a cooling protocol. After ≈96 h had elapsed, the subjects then returned on two further days (approx. 48 h apart) at 08:00 h or 18:00 in random order. On both the latter days, the resting energy expenditure (REE) was measured before the subjects underwent personalized cold exposure (i.e., according to their shivering threshold). CIT was then assessed for 60 min by indirect calorimetry. In an independent cross-sectional study (n = 133, 88 women), subjects came to the laboratory between 8:00 and 18:00 h and their BAT 18F-fluordeoxyglucose (18F-FDG) uptake was assessed after personalized cold stimulation. RESULTS: Both the REE and CIT were similar in the morning and evening (all P > 0.05). Indeed, 60 min of personalized-mild cold exposure in the morning or evening elicited a similar change in energy expenditure (16.8 ± 12.8 vs. 15.7 ± 15.1% increase above REE, P = 0.72). BAT 18F-FDG uptake was also similar in the morning, evening and afternoon (all P > 0.05). CONCLUSION: CIT does not appear to show morning/evening variation in young healthy adults, with the current study design and methodology. BAT 18F-FDG uptake appears not to change across the day either, although experiments with a within-subject study design are needed to confirm these findings. Registered under ClinicalTrials.gov Identifier no. NCT02365129.


Assuntos
Tecido Adiposo Marrom/metabolismo , Ritmo Circadiano , Metabolismo Energético , Fluordesoxiglucose F18/metabolismo , Termogênese , Tecido Adiposo Marrom/química , Adulto , Calorimetria Indireta , Temperatura Baixa , Estudos Cross-Over , Estudos Transversais , Feminino , Fluordesoxiglucose F18/análise , Voluntários Saudáveis , Humanos , Masculino , Estremecimento
19.
Diabetes ; 70(7): 1473-1485, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33858825

RESUMO

Human brown adipose tissue (BAT) volume has consistently been claimed to be inversely associated with whole-body adiposity. However, recent advances in the assessment of human BAT suggest that previously reported associations may have been biased. The present cross-sectional study investigates the association of BAT volume, mean radiodensity, and 18F-fluorodeoxyglucose (18F-FDG) uptake (assessed via a static positron emission tomography [PET]-computed tomography [CT] scan after a 2-h personalized cold exposure) with whole-body adiposity (measured by DXA) in 126 young adults (42 men and 84 women; mean ± SD BMI 24.9 ± 4.7 kg/m2). BAT volume, but not 18F-FDG uptake, was positively associated with BMI, fat mass, and visceral adipose tissue (VAT) mass in men but not in women. These associations were independent of the date when the PET-CT was performed, insulin sensitivity, and body surface area. BAT mean radiodensity, an inverse proxy of BAT fat content, was negatively associated with BMI, fat mass, and VAT mass in men and in women. These results refute the widely held belief that human BAT volume is reduced in obese persons, at least in young adults, and suggest that it might even be the opposite in young men.


Assuntos
Tecido Adiposo Marrom/metabolismo , Adiposidade , Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Marrom/patologia , Composição Corporal , Estudos Transversais , Feminino , Fluordesoxiglucose F18/farmacocinética , Humanos , Hipertrofia , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Caracteres Sexuais , Adulto Jovem
20.
Eur J Endocrinol ; 185(2): 209-218, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34061765

RESUMO

PURPOSE: Thyroid hormones (THs) are important mediators of brown adipose tissue (BAT) differentiation. However, the association of TH concentrations with human BAT is unclear. The present work examines the associations between circulating thyroid-stimulating hormone (TSH) and THs concentrations (i.e. free triiodothyronine, FT3, and free thyroxine, FT4), under thermoneutral (22-23°C) and cold-induced conditions, and BAT volume, 18F-fluorodeoxyglucose (18F-FDG) uptake and mean radiodensity. METHODS: A total of 106 young healthy, euthyroid adults (34 men/72 women; 22.0 ± 2.1 years old; 24.9 ± 4.6 kg/m2) participated in this cross-sectional study. BAT volume, 18F-FDG uptake and mean radiodensity were assessed after 2 h of personalized (i.e. contemplating each individual's shivering threshold) cold exposure via positron emission tomography/computed tomography (PET/CT) static scanning. TSH and THs levels were determined before (thermoneutral) and 1 h after the cold exposure. RESULTS: Cold exposure increased circulating FT4 (P = 0.038) and reduced TSH levels (P ≤ 0.001). Conversely, the FT3 serum concentration was not modified by cold exposure (P = 0.435). No associations were found between the TSH and THs thermoneutral (all P > 0.111) or cold-induced levels (all P > 0.067) and BAT volume, 18F-FDG uptake and mean radiodensity. These findings were independent of sex and BMI. CONCLUSIONS: Thyroid function is modulated by cold exposure, yet it is not associated with BAT volume or glucose metabolism assessed after 2 h of cold exposure in young healthy, euthyroid adults.


Assuntos
Tecido Adiposo Marrom/metabolismo , Fluordesoxiglucose F18/farmacocinética , Glândula Tireoide/fisiologia , Tecido Adiposo Marrom/diagnóstico por imagem , Adulto , Composição Corporal/fisiologia , Temperatura Baixa , Estudos Transversais , Feminino , Humanos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Termogênese/fisiologia , Testes de Função Tireóidea , Glândula Tireoide/diagnóstico por imagem , Hormônios Tireóideos/metabolismo , Tireotropina/metabolismo , Adulto Jovem
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