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1.
Cell Mol Life Sci ; 80(5): 122, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37052684

RESUMO

OBJECTIVE: Intriguingly, hyperinsulinemia, and hyperglycemia can predispose insulin resistance, obesity, and type 2 diabetes, leading to metabolic disturbances. Conversely, physical exercise stimulates skeletal muscle glucose uptake, improving whole-body glucose homeostasis. Therefore, we investigated the impact of short-term physical activity in a mouse model (Slc2a4+/-) that spontaneously develops hyperinsulinemia and hyperglycemia even when fed on a chow diet. METHODS: Slc2a4+/- mice were used, that performed 5 days of endurance or strength exercise training. Further analysis included physiological tests (GTT and ITT), skeletal muscle glucose uptake, skeletal muscle RNA-sequencing, mitochondrial function, and experiments with C2C12 cell line. RESULTS: When Slc2a4+/- mice were submitted to the endurance or strength training protocol, improvements were observed in the skeletal muscle glucose uptake and glucose metabolism, associated with broad transcriptomic modulation, that was, in part, related to mitochondrial adaptations. The endurance training, but not the strength protocol, was effective in improving skeletal muscle mitochondrial activity and unfolded protein response markers (UPRmt). Moreover, experiments with C2C12 cells indicated that insulin or glucose levels could contribute to these mitochondrial adaptations in skeletal muscle. CONCLUSIONS: Both short-term exercise protocols were efficient in whole-body glucose homeostasis and insulin resistance. While endurance exercise plays an important role in transcriptome and mitochondrial activity, strength exercise mostly affects post-translational mechanisms and protein synthesis in skeletal muscle. Thus, the performance of both types of physical exercise proved to be a very effective way to mitigate the impacts of hyperglycemia and hyperinsulinemia in the Slc2a4+/- mouse model.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Resistência à Insulina , Camundongos , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Músculo Esquelético/metabolismo , Hiperglicemia/genética , Hiperglicemia/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 4/metabolismo
2.
Eur J Nucl Med Mol Imaging ; 50(8): 2432-2440, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36988710

RESUMO

PURPOSE: The aim of this study was to compare [18F]FDG and [68Ga]Ga-PSMA-11 PET/CT image findings in patients with multiple myeloma (MM). METHODS: Twenty consecutive patients with symptomatic biopsy-proven MM were submitted to whole body [18F]FDG and [68Ga]Ga-PSMA-11 PET/CT with a time interval of 1-8 days between procedures. All lesions were counted and had their maximum SUV (SUVmax) measured. Intra-class correlation (ICC) was used to assess the agreement between [18F]FDG and [68Ga]Ga-PSMA-11 PET/CT findings. RESULTS: A total of 266 lesions were detected in 19/20 patients. [18F]FDG detected 223/266 (84%) lesions in 17 patients and [68Ga]Ga-PSMA-11 190/266 (71%) lesions in 19 patients. Both procedures did not identify any active lesion in 1 patient. Forty-three (16%) lesions were detected only by [68Ga]Ga-PSMA-11 and 76 (29%) only by [18F]FDG. Both tracers identified 147 (55%) lesions. Intralesional mismatch of FDG-PSMA uptake was identified in 25 of these 147 lesions, found in 8 different patients. Different lesions with uptake of only [18F]FDG or [68Ga]Ga-PSMA-11 in the same patient were found in 4 patients. The highest SUVmax of [18F]FDG and [68Ga]Ga-PSMA-11 had a median (min-max) SUVmax of 6.5 (2.0-37.8) and 5.5 (1.7-51.3), respectively. [18F]FDG and [68Ga]Ga-PSMA-11 respectively identified 18 and 19 soft tissue lesions. False-positive [18F]FDG findings had minimal or no uptake of [68Ga]Ga-PSMA-11. Good reliability (ICC ≥ 0.75) was found for number of lesions, number of soft tissue lesions and highest SUVmax in each patient. CONCLUSION: [18F]FDG or [68Ga]Ga-PSMA-11 alone can detect most MM lesions. Almost half of the lesions take up only one of the tracers, reflecting increased glycolysis or angiogenesis in specific lesions, and suggesting their possible complementary role in MM. The marked [68Ga]Ga-PSMA-11 uptake in some cases raises the possibility of a theranostic approach in selected patients.


Assuntos
Radioisótopos de Gálio , Mieloma Múltiplo , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Mieloma Múltiplo/diagnóstico por imagem , Reprodutibilidade dos Testes
3.
Perfusion ; 38(3): 637-644, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35225074

RESUMO

INTRODUCTION: Computed tomography angiography (CTA) and ventilation/perfusion (V/Q) single photon emission computed tomography/CT (SPECT/CT) images have been widely used to detect PE, but few studies have performed a direct comparison between them. We aimed to evaluate the performance of these tests in the same group of patients, selected from the routine practice of a general hospital. METHODS: Patients with suspected acute PE were prospectively submitted to CTA and V/Q SPECT/CT. General radiologists and nuclear physicians, respectively, interpreted the images. Data regarding age, sex, time between examinations, symptoms, and Wells score were also recorded. The final diagnosis was decided through a consensus among the clinicians, taking into account clinical, laboratory, follow-up, and all imaging procedures data. RESULTS: Twenty-eight patients (15 male, 13 female, and median age of 51.5 years) were studied. Median duration of the onset of symptoms was 4 (1-14) days, and the median Wells score was 3.5 (1.5-6). Sensitivity, specificity, positive and negative predictive values, and accuracy were 84.6%, 80.0%, 78.6%, 85.7%, and 82.1% for V/Q SPECT/CT, and 46.1%, 100%, 100%, 68.2%, and 75.0% for CTA. The overall agreement between the methods was 57.1%. Of the 22 patients with negative CTA, 10 (45.4%) had positives V/Q SPECT/CT and seven of them classified as true positives. CONCLUSIONS: Our results suggest that V/Q SPECT/CT is more sensitive and accurate than CTA when interpreted by general radiologists and nuclear medicine physicians.


Assuntos
Tomografia Computadorizada Multidetectores , Embolia Pulmonar , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Relação Ventilação-Perfusão , Embolia Pulmonar/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Angiografia , Doença Aguda , Perfusão
4.
Pharmaceutics ; 13(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34683846

RESUMO

Melanoma is the most aggressive skin carcinoma and nanotechnology can bring new options for its pharmacological treatment. Nanostructured lipid carriers (NLC) are ideal drug-delivery carriers for hydrophobic drugs, such as the antineoplastic docetaxel (DTX), and hybrid (NLC-in-hydrogel) systems are suitable for topical application. This work describes a formulation of NLCDTX in xanthan-chitosan hydrogel containing lidocaine (LDC) with anticancer and analgesia effects. The optimized nanoparticles encapsulated 96% DTX and rheological analysis revealed inherent viscoelastic properties of the hydrogel. In vitro assays over murine fibroblasts (NIH/3T3) and melanoma cells (B16-F10), human keratinocytes (HaCaT) and melanoma cells (SK-MEL-103) showed reduction of docetaxel cytotoxicity after encapsulation in NLCDTX and HGel-NLCDTX. Addition of LDC to the hybrid system (HGel-NLCDTX-LDC) increased cell death in tumor and normal cells. In vivo tests on C57BL/6J mice with B16-F10-induced melanoma indicated that LDC, NLCDTX, HGel-NLCDTX-LDC and NLCDTX + HGel-LDC significantly inhibited tumor growth while microPET/SPECT/CT data suggest better prognosis with the hybrid treatment. No adverse effects were observed in cell survival, weight/feed-consumption or serum biochemical markers (ALT, AST, creatinine, urea) of animals treated with NLCDTX or the hybrid system. These results confirm the adjuvant antitumor effect of lidocaine and endorse HGel-NLCDTX-LDC as a promising formulation for the topical treatment of melanoma.

5.
J Neurosci ; 41(48): 10004-10022, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34675088

RESUMO

Nescient helix-loop-helix 2 (NHLH2) is a hypothalamic transcription factor that controls the expression of prohormone convertase 1/3, therefore having an impact on the processing of proopiomelanocortin and thus on energy homeostasis. Studies have shown that KO of Nhlh2 results in increased body mass, reduced physical activity, and hypogonadism. In humans, a polymorphism of the NHLH2 gene is associated with obesity; and in Prader-Willi syndrome, a condition characterized by obesity, hypogonadism and behavioral abnormalities, the expression of NHLH2 is reduced. Despite clinical and experimental evidence suggesting that NHLH2 could be a good target for the treatment of obesity, no previous study has evaluated the impact of NHLH2 overexpression in obesity. Here, in mice fed a high-fat diet introduced right after the arcuate nucleus intracerebroventricular injection of a lentivirus that promoted 40% increase in NHLH2, there was prevention of the development of obesity by a mechanism dependent on the reduction of caloric intake. When hypothalamic overexpression of NHLH2 was induced in previously obese mice, the beneficial impact on obesity-associated phenotype was even greater; thus, there was an 80% attenuation in body mass gain, reduced whole-body adiposity, increased brown adipose tissue temperature, reduced hypothalamic inflammation, and reduced liver steatosis. In this setting, the beneficial impact of hypothalamic overexpression of NHLH2 was a result of combined effects on caloric intake, energy expenditure, and physical activity. Moreover, the hypothalamic overexpression of NHLH2 reduced obesity-associated anxiety/depression behavior. Thus, we provide an experimental proof of concept supporting that hypothalamic NHLH2 is a good target for the treatment of obesity.SIGNIFICANCE STATEMENT Obesity is a highly prevalent medical condition that lacks an effective treatment. The main advance provided by this study is the demonstration of the beneficial metabolic and behavioral outcomes resulting from the overexpression of NHLH2 in the hypothalamus. When NHLH2 was overexpressed simultaneously with the introduction of a high-fat diet, there was prevention of obesity by a mechanism dependent on reduced caloric intake. Conversely, when NHLH2 was overexpressed in previously obese mice, there was reduction of the obese phenotype because of a combination of reduced caloric intake, increased physical activity, and increased thermogenesis. In addition, the overexpression of NHLH2 reduced anxiety/depression-like behavior. Thus, NHLH2 emerges as a potential target for the combined treatment of obesity and its associated anxiety/depression-like behavior.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Obesidade/metabolismo , Animais , Ansiedade/metabolismo , Índice de Massa Corporal , Depressão/metabolismo , Dieta Hiperlipídica/efeitos adversos , Feminino , Masculino , Camundongos , Obesidade/psicologia
6.
J Nucl Med Technol ; 48(1): 30-35, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31604902

RESUMO

Quantification of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) can be time-consuming. We evaluated the performance of an automatic multifocal segmentation (MFS) method of quantification in patients with different stages of Hodgkin lymphoma, using the multiple VOI (MV) method as reference. Methods: This prospective bicentric study included 50 patients with Hodgkin lymphoma who underwent staging 18F-FGD PET/CT. The examinations were centrally reviewed and processed with commercial MFS software to obtain MTV and TLG using 2 fixed relative thresholds (40% and 20% of SUVmax) for each lesion. All PET/CT scans were processed using the MV and MFS methods. Interclass correlation coefficients and Bland-Altman plots were used for statistical analysis. Repeated calculations of MTV and TLG values by 2 observers with different degrees of PET/CT imaging experience were used to ascertain interobserver agreement on the MFS method. Results: The means and SDs obtained for the MTV with MV and MFS were, respectively, 736 ± 856 mL and 660 ± 699 mL for the 20% threshold and 313 ± 359 mL and 372 ± 434 mL for the 40% threshold. The time spent calculating the MTV was much shorter with the MFS method than with the MV method (median time, 11.6 min [range, 1-30 min] and 64.4 min [range, 1-240 min], respectively), especially in patients with advanced disease. Time spent was similar in patients with localized disease. There were no statistical differences between the MFS values obtained by the 2 different observers. Conclusion: MTV and TLG calculations using MFS are reproducible, generate similar results to those obtained with MV, and are much less timing-consuming. Main differences between the 2 methods were related to difficulties in avoiding overlay of VOIs in the MV technique. MV and MFS perform equally well in patients with a small number of lesions.


Assuntos
Fluordesoxiglucose F18/farmacologia , Doença de Hodgkin/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos/farmacologia , Carga Tumoral/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Fluordesoxiglucose F18/química , Glicólise , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Compostos Radiofarmacêuticos/química , Estudos Retrospectivos , Fatores de Tempo
7.
Sci Rep ; 9(1): 16429, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712729

RESUMO

Many efforts have been made to standardize the interpretation of 18F-FDG PET/CT in multiple myeloma (MM) with qualitative visual analysis or with quantitative metabolic parameters using various methods for lesion segmentation of PET images. The aim of this study was to propose a quantitative method for bone and bone marrow evaluation of 18F-FDG PET/CT considering the extent and intensity of bone 18F-FDG uptake: Intensity of Bone Involvement (IBI). Whole body 18F-FDG PET/CT of 59 consecutive MM patients were evaluated. Compact bone tissue was segmented in PET images using a global threshold for HU of the registered CT image. A whole skeleton mask was created and the percentage of its volume with 18F-FDG uptake above hepatic uptake was calculated (Percentage of Bone Involvement - PBI). IBI was defined by multiplying PBI by mean SUV above hepatic uptake. IBI was compared with visual analysis performed by two experienced nuclear medicine physicians. IBI calculation was feasible in all images (range:0.00-1.35). Visual analysis categorized PET exams into three groups (negative/mild, moderate and marked bone involvement), that had different ranges of IBI (multi comparison analysis, p < 0.0001). There was an inverse correlation between the patients' hemoglobin values and IBI (r = -0.248;p = 0.02). IBI score is an objective measure of bone and bone marrow involvement in MM, allowing the categorization of patients in different degrees of aggressiveness of the bone disease. The next step is to validate IBI in a larger group of patients, before and after treatment and in a multicentre setting.


Assuntos
Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Fluordesoxiglucose F18 , Mieloma Múltiplo/diagnóstico por imagem , Mieloma Múltiplo/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Osso e Ossos/metabolismo , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Mieloma Múltiplo/metabolismo , Osteólise , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos
8.
Acta Diabetol ; 56(12): 1333-1339, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31506721

RESUMO

AIMS: This study aimed to evaluate the effect of pioglitazone on brown adipose tissue function and hypothalamic gliosis in humans. Brown adipose tissue and the hypothalamus are regarded as important potential pharmacological targets to metabolic diseases, and defining the impact of current therapies on their structure and/or function could provide therapeutic advance in this field. METHODS: Six patients with type 2 diabetes were treated for 24 weeks with pioglitazone 30 mg/day as an add-on therapy. Brown adipose tissue glucose uptake and volume were determined using 18F-FDG PET/CT scans; hypothalamic gliosis was determined using MRI scans; blood was collected for hormone and biochemistry measurements. All tests were performed at inclusion and six months after pioglitazone introduction. RESULTS: Pioglitazone treatment led to a significant 3% body mass increase. There were neither changes in cold-induced brown adipose tissue glucose uptake and volume nor changes in hypothalamic gliosis. CONCLUSIONS: This is a proof-of-concept study that provides clinical evidence for a lack of action of a thiazolidinedione, pioglitazone, to promote homogeneous and measurable changes in brown adipose tissue volume and also in hypothalamic gliosis after 6 months of treatment.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Gliose/prevenção & controle , Hipotálamo/efeitos dos fármacos , Hipotálamo/patologia , Pioglitazona/farmacologia , Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Marrom/patologia , Adulto , Idoso , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/patologia , Quimioterapia Combinada , Feminino , Fluordesoxiglucose F18 , Gliose/diagnóstico , Gliose/patologia , Humanos , Hipotálamo/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/diagnóstico , Obesidade/tratamento farmacológico , Obesidade/patologia , Tamanho do Órgão/efeitos dos fármacos , Sobrepeso/complicações , Sobrepeso/diagnóstico , Sobrepeso/tratamento farmacológico , Sobrepeso/patologia , Pioglitazona/administração & dosagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudo de Prova de Conceito , Tiazolidinedionas/administração & dosagem , Tiazolidinedionas/farmacologia
9.
Sci Rep ; 9(1): 9312, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31249357

RESUMO

Cisplatin (CDDP) combined with radiotherapy (RT) is employed in head and neck squamous cell carcinoma (HNSCC) with variable toxicities and clinical response. Glutathione S-transferases (GSTs) participate in CDDP excretion from cells, and genes encoding GSTs, GSTM1, GSTT1and GSTP1, are polymorphic in humans. This prospective study aimed to evaluate the roles of GSTM1, GSTT1, and GSTP1 Ile105Val polymorphisms in outcomes of HNSCC patients treated with CDDP chemoradiation. Ninety patients were genotyped by multiplex PCR. Urinary CDDP measurements were performed by HPLC. Treatment side effects and response were analysed by conventional criteria. Patients with GSTT1 genes showed 7.23- and 5.37-fold higher likelihood of presenting vomiting and ototoxicity, lower glomerular filtration rate (GFR), and lower elimination of CDDP in urine relative to patients with deleted genes. Patients harbouring the GSTP1 IleVal or ValVal genotypes showed 4.28-fold higher likelihood of presenting grade 2 or 3 vomiting and lower GFR with treatment than those harbouring the IleIle genotype. In multivariate Cox analysis, patients with the GSTP1 105ValVal genotype had 3.87 more chance of presenting disease progression than those with the IleIle or IleVal genotype (p < 0.01). Our findings provide preliminary evidence that inherited abnormalities in CDDP metabolism, related to GSTT1 and GSTP1 Ile105Val polymorphisms, alter outcomes of HNSCC patients treated with CDDP and RT.


Assuntos
Quimiorradioterapia , Cisplatino/farmacologia , Glutationa S-Transferase pi/genética , Glutationa Transferase/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Adulto , Idoso , Cisplatino/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Análise de Sobrevida , Resultado do Tratamento
10.
EBioMedicine ; 39: 436-447, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30502051

RESUMO

BACKGROUND: Inflammation is the most relevant mechanism linking obesity with insulin-resistance and metabolic disease. It impacts the structure and function of tissues and organs involved in metabolism, such as the liver, pancreatic islets and the hypothalamus. Brown adipose tissue has emerged as an important component of whole body energy homeostasis, controlling caloric expenditure through the regulation of non-shivering thermogenesis. However, little is known about the impact of systemic inflammation on the structure and function of brown adipose tissue. METHODS: The relations between IL10 and mitochondria structure/function and also with thermogenesis were evaluated by bioinformatics using human and rodent data. Real-time PCR, immunoblot, fluorescence and transmission electron microscopy were employed to determine the effect of IL10 in the brown adipose tissue of wild type and IL10 knockout mice. FINDINGS: IL10 knockout mice, a model of systemic inflammation, present severe structural abnormalities of brown adipose tissue mitochondria, which are round-shaped with loss of cristae structure and increased fragmentation. IL10 deficiency leads to newborn cold intolerance and impaired UCP1-dependent brown adipose tissue mitochondrial respiration. The reduction of systemic inflammation with an anti-TNFα monoclonal antibody partially rescued the structural but not the functional abnormalities of brown adipose tissue mitochondria. Using bioinformatics analyses we show that in both humans and mice, IL10 transcripts correlate with mitochondrial lipid metabolism and caspase gene expression. INTERPRETATION: IL10 and systemic inflammation play a central role in the regulation of brown adipose tissue by controlling mitochondrial structure and function. FUND: Sao Paulo Research Foundation grant 2013/07607-8.


Assuntos
Tecido Adiposo Marrom/citologia , Inflamação/patologia , Interleucina-10/genética , Mitocôndrias/patologia , Estremecimento/genética , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/patologia , Animais , Caspases/genética , Linhagem Celular , Temperatura Baixa , Biologia Computacional/métodos , Metabolismo Energético , Técnicas de Inativação de Genes , Humanos , Inflamação/genética , Inflamação/metabolismo , Metabolismo dos Lipídeos , Masculino , Camundongos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteína Desacopladora 1/metabolismo
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