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1.
Am J Physiol Endocrinol Metab ; 326(3): E398-E406, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38324260

RESUMO

Resveratrol, a natural polyphenol compound contained in numerous plants, has been proposed as a treatment for obesity-related disease processes such as insulin resistance. However, in humans there are conflicting results concerning the efficacy of resveratrol in improving insulin action; the purpose of the present study was to determine whether obesity status (lean, severely obese) affects the response to resveratrol in human skeletal muscle. Primary skeletal muscle cells were derived from biopsies obtained from age-matched lean and insulin-resistant women with severe obesity and incubated with resveratrol (1 µM) for 24 h. Insulin-stimulated glucose oxidation and incorporation into glycogen, insulin signal transduction, and energy-sensitive protein targets [AMP-activated protein kinase (AMPK), Sirt1, and PGC1α] were analyzed. Insulin-stimulated glycogen synthesis, glucose oxidation, and AMPK phosphorylation increased with resveratrol incubation compared with the nonresveratrol conditions (main treatment effect for resveratrol). Resveratrol further increased IRS1, Akt, and TBC1D4 insulin-stimulated phosphorylation and SIRT1 content in myotubes from lean women, but not in women with severe obesity. Resveratrol improves insulin action in primary human skeletal myotubes derived from lean women and women with severe obesity. In women with obesity, these improvements may be associated with enhanced AMPK phosphorylation with resveratrol treatment.NEW & NOTEWORTHY A physiologically relevant dose of resveratrol increases insulin-stimulated glucose oxidation and glycogen synthesis in myotubes from individuals with severe obesity. Furthermore, resveratrol improved insulin signal transduction in myotubes from lean individuals but not from individuals with obesity. Activation of AMPK plays a role in resveratrol-induced improvements in glucose metabolism in individuals with severe obesity.


Assuntos
Resistência à Insulina , Obesidade Mórbida , Humanos , Feminino , Obesidade Mórbida/metabolismo , Resveratrol/farmacologia , Sirtuína 1/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Obesidade/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Insulina/farmacologia , Insulina/metabolismo , Glucose/metabolismo , Resistência à Insulina/fisiologia , Glicogênio/metabolismo
2.
Prostate ; 84(9): 814-822, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38558458

RESUMO

BACKGROUND: Tumor initiation and progression necessitate a metabolic shift in cancer cells. Consequently, the progression of prostate cancer (PCa), a leading cause of cancer-related deaths in males globally, involves a shift from lipogenic to glycolytic metabolism. Androgen deprivation therapy (ADT) serves as the standard treatment for advanced-stage PCa. However, despite initial patient responses, castrate resistance emerges ultimately, necessitating novel therapeutic approaches. Therefore, in this study, we aimed to investigate the role of monocarboxylate transporters (MCTs) in PCa post-ADT and evaluate their potential as therapeutic targets. METHODS: PCa cells (LNCaP and C4-2 cell line), which has high prostate-specific membrane antigen (PSMA) and androgen receptor (AR) expression among PCa cell lines, was used in this study. We assessed the expression of MCT1 in PCa cells subjected to ADT using charcoal-stripped bovine serum (CSS)-containing medium or enzalutamide (ENZ). Furthermore, we evaluated the synergistic anticancer effects of combined treatment with ENZ and SR13800, an MCT1 inhibitor. RESULTS: Short-term ADT led to a significant upregulation in folate hydrolase 1 (FOLH1) and solute carrier family 16 member 1 (SLC16A1) gene levels, with elevated PSMA and MCT1 protein levels. Long-term ADT induced notable changes in cell morphology with further upregulation of FOLH1/PSMA and SLC16A1/MCT1 levels. Treatment with ENZ, a nonsteroidal anti-androgen, also increased PSMA and MCT1 expression. However, combined therapy with ENZ and SR13800 led to reduced PSMA level, decreased cell viability, and suppressed expression of cancer stem cell markers and migration indicators. Additionally, analysis of human PCa tissues revealed a positive correlation between PSMA and MCT1 expression in tumor regions. CONCLUSIONS: Our results demonstrate that ADT led to a significant upregulation in MCT1 levels. However, the combination of ENZ and SR13800 demonstrated a promising synergistic anticancer effect, highlighting a potential therapeutic significance for patients with PCa undergoing ADT.


Assuntos
Antagonistas de Androgênios , Benzamidas , Transportadores de Ácidos Monocarboxílicos , Nitrilas , Feniltioidantoína , Neoplasias da Próstata , Simportadores , Masculino , Humanos , Transportadores de Ácidos Monocarboxílicos/metabolismo , Transportadores de Ácidos Monocarboxílicos/antagonistas & inibidores , Transportadores de Ácidos Monocarboxílicos/genética , Linhagem Celular Tumoral , Feniltioidantoína/farmacologia , Feniltioidantoína/análogos & derivados , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Nitrilas/farmacologia , Simportadores/metabolismo , Simportadores/antagonistas & inibidores , Simportadores/genética , Benzamidas/farmacologia
3.
BMC Oral Health ; 24(1): 442, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605361

RESUMO

BACKGROUND: Radiolucencies found at the root apex in patients with cemento-osseous dysplasia (COD) may be mistaken for periapical cysts (PC) of endodontic origin. The purpose of this study was to examine the utility of quantitative texture analysis using cone-beam computed tomography (CBCT) to differentiate between COD and PC. METHODS: Patients who underwent CBCT at Wonkwang University Daejeon Dental Hospital between January 2019 and December 2022 and were diagnosed with COD and PC by clinical, radiologic, and, if necessary, histopathologic examination were included. Twenty-five patients each were retrospectively enrolled in the COD and PC group. All lesions observed on axial CBCT images were manually segmented using the open-access software MaZda version 4.6 to establish the regions of interest, which were then subjected to texture analysis. Among the 279 texture features obtained, 10 texture features with the highest Fisher coefficients were selected. Statistical analysis was performed using the Mann-Whitney U-test, Welch's t-test, or Student's t-test. Texture features that showed significant differences were subjected to receiver operating characteristics (ROC) curve analysis to evaluate the differential diagnostic ability of COD and PC. RESULTS: The COD group consisted of 22 men and 3 women, while the PC group consisted of 14 men and 11 women, showing a significant difference between the two groups in terms of sex (p=0.003). The 10 selected texture features belonged to the gray level co-occurrence matrix and included the sum of average, sum of entropy, entropy, and difference of entropy. All 10 selected texture features showed statistically significant differences (p<0.05) when comparing patients with COD (n=25) versus those with PC (n=25), osteolytic-stage COD (n=11) versus PC (n=25), and osteolytic-stage COD (n=11) versus cementoblastic-stage COD (n=14). ROC curve analysis to determine the ability to differentiate between COD and PC showed a high area under the curve ranging from 0.96 to 0.98. CONCLUSION: Texture analysis of CBCT images has shown good diagnostic value in the differential diagnosis of COD and PC, which can help prevent unnecessary endodontic treatment, invasive biopsy, or surgical intervention associated with increased risk of infection.


Assuntos
Tumores Odontogênicos , Cisto Radicular , Tomografia Computadorizada de Feixe Cônico Espiral , Masculino , Humanos , Feminino , Cisto Radicular/diagnóstico por imagem , Estudos Retrospectivos , Diagnóstico Diferencial , Tomografia Computadorizada de Feixe Cônico/métodos
4.
Kidney Int ; 104(4): 724-739, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37399974

RESUMO

Ischemia-reperfusion (IR) injury, a leading cause of acute kidney injury (AKI), is still without effective therapies. Succinate accumulation during ischemia followed by its oxidation during reperfusion leads to excessive reactive oxygen species (ROS) and severe kidney damage. Consequently, the targeting of succinate accumulation may represent a rational approach to the prevention of IR-induced kidney injury. Since ROS are generated primarily in mitochondria, which are abundant in the proximal tubule of the kidney, we explored the role of pyruvate dehydrogenase kinase 4 (PDK4), a mitochondrial enzyme, in IR-induced kidney injury using proximal tubule cell-specific Pdk4 knockout (Pdk4ptKO) mice. Knockout or pharmacological inhibition of PDK4 ameliorated IR-induced kidney damage. Succinate accumulation during ischemia, which is responsible for mitochondrial ROS production during reperfusion, was reduced by PDK4 inhibition. PDK4 deficiency established conditions prior to ischemia resulting in less succinate accumulation, possibly because of a reduction in electron flow reversal in complex II, which provides electrons for the reduction of fumarate to succinate by succinate dehydrogenase during ischemia. The administration of dimethyl succinate, a cell-permeable form of succinate, attenuated the beneficial effects of PDK4 deficiency, suggesting that the kidney-protective effect is succinate-dependent. Finally, genetic or pharmacological inhibition of PDK4 prevented IR-induced mitochondrial damage in mice and normalized mitochondrial function in an in vitro model of IR injury. Thus, inhibition of PDK4 represents a novel means of preventing IR-induced kidney injury, and involves the inhibition of ROS-induced kidney toxicity through reduction in succinate accumulation and mitochondrial dysfunction.


Assuntos
Traumatismo por Reperfusão , Ácido Succínico , Camundongos , Animais , Ácido Succínico/farmacologia , Espécies Reativas de Oxigênio , Camundongos Knockout , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Isquemia/tratamento farmacológico , Rim , Mitocôndrias , Reperfusão
5.
Environ Geochem Health ; 45(5): 2349-2358, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35960422

RESUMO

Trace element concentrations and isotope ratios of hair reflect the blood levels at the time of hair formation, but can be affected by external factors such as dyeing, bleaching, and bathing. To investigate the effect of dyeing, bleaching, and bathing on hair, hair was immersed in tap water, and changes in trace element concentrations and the Sr isotope ratio were observed over time. During soaking, alkaline earth metals (Ca, Mg, and Sr) from tap water were gradually absorbed into the hair over time. After about one day, the adsorption capacity of hair reached a maximum and the reverse reaction started to occur. In contrast, alkaline metals (Na and K) behaved in reverse. In dyed and bleached hair, Na was significantly desorbed from the hair and gradually migrated to the water over time. The adsorption and desorption of trace elements were minimal in untreated original hair, but much higher in dyed and bleached hair. Thus, dyeing and bleaching appear to damage the hair surface structure and greatly promote the exchange of trace elements. The rapid exchange of trace elements, including Sr, between hair and tap water observed in this study indicates that hair samples can be easily contaminated during bathing.


Assuntos
Oligoelementos , Humanos , Oligoelementos/análise , Corantes , Metais/análise , Cabelo/química , Água/análise , Sódio/análise
6.
J Toxicol Environ Health B Crit Rev ; 25(8): 393-404, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36250612

RESUMO

Read-across, an alternative approach for hazard assessment, has been widely adopted when in vivo data are unavailable for chemicals of interest. Read-across is enabled via in silico tools such as quantitative structure activity relationship (QSAR) modeling. In this study, the current status of structure activity relationship (SAR)-based read-across applications in the Republic of Korea (ROK) was examined considering both chemical risk assessments and chemical registrations from different sectors, including regulatory agencies, industry, and academia. From the regulatory perspective, the Ministry of Environment (MOE) established the Act on Registration and Evaluation of Chemicals (AREC) in 2019 to enable registrants to submit alternative data such as information from read-across instead of in vivo data to support hazard assessment and determine chemical-specific risks. Further, the Ministry of Food and Drug Safety (MFDS) began to consider read-across approaches for establishing acceptable intake (AI) limits of impurities occurring during pharmaceutical manufacturing processes under the ICH M7 guideline. Although read-across has its advantages, this approach also has limitations including (1) lack of standardized criteria for regulatory acceptance, (2) inconsistencies in the robustness of scientific evidence, and (3) deficiencies in the objective reliability of read-across data. The application and acceptance rate of read-across may vary among regulatory agencies. Therefore, sufficient data need to be prepared to verify the hypothesis that structural similarities might lead to similarities in properties of substances (between source and target chemicals) prior to adopting a read-across approach. In some cases, additional tests may be required during the registration process to clarify long-term effects on human health or the environment for certain substances that are data deficient. To improve the quality of read-across data for regulatory acceptance, cooperative efforts from regulatory agencies, academia, and industry are needed to minimize limitations of read-across applications.


Assuntos
Relação Quantitativa Estrutura-Atividade , Humanos , Reprodutibilidade dos Testes , Bases de Dados Factuais , Medição de Risco , República da Coreia
7.
J Toxicol Environ Health A ; 85(5): 184-197, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34670481

RESUMO

The aim of this paper was to investigate the current status of read-across approaches in the Republic of Korea, Japan, and China in terms of applications and regulatory acceptance. In the Republic of Korea, over the last 6 years, approximately 8% of safety data records used for chemical registrations were based upon read-across, and a guideline published on the use of read-across results in 2017. In Japan, read-across is generally accepted for screening hazard classification of toxicological endpoints according to the Chemical Substances Control Law (CSCL). In China, read-across data, along with data from other animal alternatives are accepted as a data source for chemical registrations, but could be only considered when testing is not technically feasible. At present, read-across is not widely used for chemical registrations and regulatory acceptance of read-across may differ among countries in Asia. With consideration of the advantages and limitations of read-across, it is expected that read-across may soon gradually be employed in Asian countries. Thus, regulatory agencies need to prepare for this progression.


Assuntos
Substâncias Perigosas/toxicidade , Medição de Risco/métodos , Toxicologia/métodos , Segurança Química , China , Japão , República da Coreia , Toxicologia/legislação & jurisprudência
8.
Int J Mol Sci ; 23(17)2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36077132

RESUMO

Our previous study shows that an essential amino acid (EAA)-enriched diet attenuates dexamethasone (DEX)-induced declines in muscle mass and strength, as well as insulin sensitivity, but does not affect endurance. In the present study, we hypothesized that the beneficial effects will be synergized by adding resistance exercise training (RET) to EAA, and diet-free EAA would improve endurance. To test hypotheses, mice were randomized into the following four groups: control, EAA, RET, and EAA+RET. All mice except the control were subjected to DEX treatment. We evaluated the cumulative rate of myofibrillar protein synthesis (MPS) using 2H2O labeling and mass spectrometry. Neuromuscular junction (NMJ) stability, mitochondrial contents, and molecular signaling were demonstrated in skeletal muscle. Insulin sensitivity and glucose metabolism using 13C6-glucose tracing during oral glucose tolerance tests were analyzed. We found that EAA and RET synergistically improve muscle mass and/or strength, and endurance capacity, as well as insulin sensitivity, and glucose metabolism in DEX-treated muscle. These improvements are accomplished, in part, through improvements in myofibrillar protein synthesis, NMJ, fiber type preservation, and/or mitochondrial biogenesis. In conclusion, free EAA supplementation, particularly when combined with RET, can serve as an effective means that counteracts the adverse effects on muscle of DEX that are found frequently in clinical settings.


Assuntos
Resistência à Insulina , Treinamento Resistido , Aminoácidos Essenciais/metabolismo , Animais , Dexametasona/farmacologia , Glucose/metabolismo , Humanos , Camundongos , Força Muscular , Músculo Esquelético/metabolismo
9.
J Nutr ; 151(5): 1190-1196, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33693735

RESUMO

BACKGROUND: The Dietary Guidelines for Americans (DGAs) published an "ounce equivalents" recommendation to help consumers meet protein requirements with a variety of protein food sources. However, the metabolic equivalency of these varied protein food sources has not been established. OBJECTIVE: We have investigated the hypothesis that the anabolic responses to consumption of ounce equivalents of protein food sources would be directly related to the essential amino acid (EAA) content of the protein food source. METHODS: Following 3 d of dietary control, a total of 56 healthy young adults underwent an 8.5-h metabolic study using stable isotope tracer methodology. The changes from baseline following consumption of 1 of 7 different protein food sources were compared with the baseline value for that individual (n = 8 per group). RESULTS: Consumption of ounce equivalents of animal-based protein food sources (beef sirloin, pork loin, eggs) resulted in a greater gain in whole-body net protein balance above baseline than the ounce equivalents of plant-based protein food sources (tofu, kidney beans, peanut butter, mixed nuts; P < 0.01). The improvement in whole-body net protein balance was due to an increase in protein synthesis (P < 0.05) with all the animal protein sources, whereas the egg and pork groups also suppressed protein breakdown compared with the plant protein sources (P < 0.01). The magnitude of the whole-body net balance (anabolic) response was correlated with the EAA content of the protein food source (P < 0.001). CONCLUSION: The "ounce equivalents" of protein food sources as expressed in the DGAs are not metabolically equivalent in young healthy individuals. The magnitude of anabolic response to dietary proteins should be considered as the DGAs develop approaches to establish healthy eating patterns.


Assuntos
Dieta/normas , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/classificação , Análise de Alimentos , Adulto , Animais , Composição Corporal , Proteínas do Ovo , Humanos , Insulina/sangue , Insulina/metabolismo , Carne , Proteínas de Plantas , Adulto Jovem
10.
Eur J Nutr ; 60(2): 1141-1148, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32970234

RESUMO

PURPOSE: The purpose of the study was to determine if an actinidin protease aids gastric digestion and the protein anabolic response to dietary protein. METHODS: Hayward green kiwifruit (containing an actinidin protease) and Hort 16A gold kiwifruit (devoid of actinidin protease) were given in conjunction with a beef meal to healthy older subjects. Twelve healthy older males (N = 6) and females (N = 6) were studied with a randomized, double-blinded, crossover design to assess muscle and whole-body protein metabolism before and after ingestion of kiwifruit and 100 g of ground beef. Subjects consumed 2 of each variety of kiwifruit daily for 14 d prior to each metabolic study, and again during each study with beef intake. RESULTS: Hayward green kiwifruit consumption with beef resulted in a more rapid increase in peripheral plasma essential amino acid concentrations. There were significant time by kiwifruit intake interactions for plasma concentrations of EAAs, branched chain amino acids (BCAAs), and leucine (P < 0.01). However, there was no difference in the total amount of EAAs absorbed. As a result, there were no differences between kiwifruit in any of the measured parameters of protein kinetics. CONCLUSION: Consumption of Hayward green kiwifruit, with a beef meal facilitates protein digestion and absorption of the constituent amino acids as compared to Hort 16A gold kiwifruit. CLINICAL TRIAL: NCT04356573, April 21, 2020 "retrospectively registered".


Assuntos
Actinidia , Digestão , Estudos Cross-Over , Proteínas Alimentares/metabolismo , Método Duplo-Cego , Feminino , Frutas , Humanos , Masculino , Proteólise , Carne Vermelha
11.
Dig Dis Sci ; 65(11): 3350-3359, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31907774

RESUMO

INTRODUCTION: A decline in physical function is highly prevalent and a poor prognostic factor in cirrhosis. We assessed the benefits of a home-based physical activity program (HB-PAP) in patients with cirrhosis with a randomized pilot trial. METHODS: All participants received a personal activity tracker to monitor daily activities and were given 12 g/day of an essential amino acid supplement. The HB-PAP intervention consisted of biweekly counseling sessions to increase physical activity for 12 weeks. Six-minute walk test (6MWT) and cardiopulmonary exercise testing (CPET) assessed changes in aerobic fitness. Different anthropometric measuring tools were used for skeletal muscle and adiposity assessment. RESULTS: Seventeen patients (60% male; 29% nonalcoholic steatohepatitis/cryptogenic, 29% hepatitis C, 24% alcohol, 18% other) were randomized, 9 to HB-PAP group. There were no significant differences in MELD-sodium between HB-PAP and controls at baseline or after the 12-week intervention. By the end of study, there was a significant between-group difference in daily step count favoring the active group (2627 [992-4262], p = 0.001), with less sedentary patients in the active group (33-17% vs. 25-43%, p = 0.003). The 6MWT improved in the HB-PAP group (423 ± 26 m vs. 482 ± 35 m), while the controls had a nonsignificant drop (418 ± 26 m vs. 327 ± 74 m) with a significant between-group difference. CPET did not change. Other than an improvement in psoas muscle index, there were no differences in anthropometry, or in quality of life. CONCLUSIONS: HB-PAP maintained physical performance and improved aerobic fitness according to 6MWT but not CPET, supporting the use of personal activity trackers to monitor/guide home-based prehabilitation programs in cirrhosis.


Assuntos
Terapia por Exercício , Serviços de Assistência Domiciliar , Cirrose Hepática/fisiopatologia , Cirrose Hepática/terapia , Adulto , Idoso , Antropometria , Arkansas , Biópsia , Teste de Esforço , Feminino , Humanos , Cirrose Hepática/dietoterapia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Prognóstico , Qualidade de Vida , Testes de Função Respiratória , Teste de Caminhada
12.
Surg Today ; 50(8): 920-930, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32062787

RESUMO

PURPOSE: Resistin-like molecule beta (RELMß) is a small cysteine-rich protein secreted by colonic epithelial cells. RELMß mRNA and protein expressions are dramatically induced by bacterial exposure in germ-free mice. We hypothesized that RELMß has antimicrobial activity. METHODS: The antimicrobial activity of RELMß was screened by an agar spot test and confirmed by a liquid broth test. The amount of RELMß in human stools was semi-quantified by Western blot analysis. The induction of RELMß mRNA and protein expression by bacteria was measured by quantitative RT-PCR using LS174T cells. Electron microscopic immunohistochemistry was performed using polyclonal anti-RELMß antibody. RESULTS: RELMß showed antimicrobial activity against S. aureus and all MRSAs examined in a dose- and pH-dependent fashion. Western blot study showed that the amount of RELMß in healthy human stools was comparable to that exhibiting antimicrobial activity in vitro. Both RELMß mRNA and protein expression were induced by heat-inactivated S. aureus, but not by E. coli in LS174T cells. Electron microscopic immunohistochemistry showed that RELMß bound to the cell surface of S. aureus, followed by destruction of the bacterial cytoplasm. CONCLUSIONS: RELMß is a colonic antimicrobial protein and its antibacterial activity is species selective. Because RELMß is abundant in healthy human stool, RELMß may modulate gut flora.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana/métodos
13.
Can J Infect Dis Med Microbiol ; 2020: 8874309, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33488887

RESUMO

Tuberculosis (TB) is an ongoing global health problem, including in South Korea. To manage TB efficiently, it is necessary to understand the epidemiology, transmission route, and characteristics of prevailing Mycobacterium tuberculosis strains. In this study, we investigated microevolutions over time in the spoligotype patterns of M. tuberculosis isolated from TB patients in Korea. We collected 1,055 clinical M. tuberculosis isolates from 16 provinces in Korea from 1994 to 2006 and analyzed them by spoligotyping. We observed 26 subfamilies, including two large predominant families: a Beijing family (72.7%) and the T family (19.1%). Specifically, the abundance of spoligotype SIT269 from the Beijing-like subfamily significantly increased in the 2000s relative to the 1990s in Korea. This study provides an overview of the M. tuberculosis genotype trends over time in Korea. These data also indicate that we should consider the influence of the newly growing SIT269 subtype identified in the Beijing family.

14.
J Physiol ; 597(2): 449-466, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30414190

RESUMO

KEY POINTS: Exercise/exercise training can enhance insulin sensitivity through adaptations in skeletal muscle, the primary site of insulin-mediated glucose disposal; however, in humans the range of improvement can vary substantially. The purpose of this study was to determine if obesity influences the magnitude of the exercise response in relation to improving insulin sensitivity in human skeletal muscle. Electrical pulse stimulation (EPS; 24 h) of primary human skeletal muscle myotubes improved insulin action in tissue from both lean and severely obese individuals, but responses to EPS were blunted with obesity. EPS improved insulin signal transduction in myotubes from lean but not severely obese subjects and increased AMP accumulation and AMPK Thr172 phosphorylation, but to a lesser degree in myotubes from the severely obese. These data reveal that myotubes of severely obese individuals enhance insulin action and stimulate exercise-responsive molecules with contraction, but in a manner and magnitude that differs from lean subjects. ABSTRACT: Exercise/muscle contraction can enhance whole-body insulin sensitivity; however, in humans the range of improvements can vary substantially. In order, to determine if obesity influences the magnitude of the exercise response, this study compared the effects of electrical pulse stimulation (EPS)-induced contractile activity upon primary myotubes derived from lean and severely obese (BMI ≥ 40 kg/m2 ) women. Prior to muscle contraction, insulin action was compromised in myotubes from the severely obese as was evident from reduced insulin-stimulated glycogen synthesis, glucose oxidation, glucose uptake, insulin signal transduction (IRS1, Akt, TBC1D4), and insulin-stimulated GLUT4 translocation. EPS (24 h) increased AMP, IMP, AMPK Thr172 phosphorylation, PGC1α content, and insulin action in myotubes of both the lean and severely obese subjects. However, despite normalizing indices of insulin action to levels seen in the lean control (non-EPS) condition, responses to EPS were blunted with obesity. EPS improved insulin signal transduction in myotubes from lean but not severely obese subjects and EPS increased AMP accumulation and AMPK Thr172 phosphorylation, but to a lesser degree in myotubes from the severely obese. These data reveal that myotubes of severely obese individuals enhance insulin action and stimulate exercise-responsive molecules with contraction, but in a manner and magnitude that differs from lean subjects.


Assuntos
Insulina/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Obesidade/metabolismo , Adulto , Células Cultivadas , Estimulação Elétrica , Exercício Físico/fisiologia , Feminino , Glucose/metabolismo , Humanos , Contração Muscular/fisiologia , Obesidade/fisiopatologia , Transdução de Sinais
15.
Am J Physiol Endocrinol Metab ; 317(1): E74-E84, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939051

RESUMO

Intrinsically labeled dietary proteins have been used to trace various aspects of digestion and absorption, including quantifying the contribution of dietary protein to observed postprandial amino acid and protein kinetics in human subjects. Quantification of the rate of appearance in peripheral blood of an unlabeled (tracee) amino acid originating from an intrinsically labeled protein (exogenous Ra) requires the assumption that there is no dilution of the isotope enrichment of the protein-bound amino acid in the gastrointestinal tract or across the splanchnic bed. It must also be assumed that the effective volume of distribution into which the tracer and tracee appear can be reasonably estimated by a single value and that any recycling of the tracer is minimal and thus does not affect calculated rates. We have assessed these assumptions quantitatively using values from published studies. We conclude that the use of intrinsically labeled proteins as currently described to quantify exogenous Ra systematically underestimates the true value. When used with the tracer-determined rates of amino acid kinetics, underestimation of exogenous Ra from the intrinsically labeled protein method likely translates to incorrect conclusions regarding protein breakdown, including the effect of a protein meal and the anabolic impact of the speed of digestion and absorption of amino acids. Estimation of exogenous Ra from the bioavailability of ingested protein has some advantages as compared with the intrinsically labeled protein method. We therefore conclude that the bioavailability method for estimating exogenous Ra is preferable to the intrinsically labeled protein method.


Assuntos
Proteínas Alimentares/farmacocinética , Marcação por Isótopo/métodos , Proteínas/metabolismo , Imagem Corporal Total/métodos , Aminoácidos/metabolismo , Aminoácidos/farmacocinética , Disponibilidade Biológica , Deutério , Proteínas Alimentares/metabolismo , Estudos de Avaliação como Assunto , Humanos , Íleo/metabolismo , Absorção Intestinal/fisiologia , Cinética , Técnicas de Sonda Molecular , Período Pós-Prandial
16.
Int J Obes (Lond) ; 43(4): 895-905, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29892037

RESUMO

BACKGROUND/OBJECTIVE: The partitioning of glucose toward glycolytic end products rather than glucose oxidation and glycogen storage is evident in skeletal muscle with severe obesity and type 2 diabetes. The purpose of the present study was to determine the possible mechanism by which severe obesity alters insulin-mediated glucose partitioning in human skeletal muscle. SUBJECTS/METHODS: Primary human skeletal muscle cells (HSkMC) were isolated from lean (BMI = 23.6 ± 2.6 kg/m2, n = 9) and severely obese (BMI = 48.8 ± 1.9 kg/m2, n = 8) female subjects. Glucose oxidation, glycogen synthesis, non-oxidized glycolysis, pyruvate oxidation, and targeted TCA cycle metabolomics were examined in differentiated myotubes under basal and insulin-stimulated conditions. RESULTS: Myotubes derived from severely obese subjects exhibited attenuated response of glycogen synthesis (20.3%; 95% CI [4.7, 28.8]; P = 0.017) and glucose oxidation (5.6%; 95% CI [0.3, 8.6]; P = 0.046) with a concomitant greater increase (23.8%; 95% CI [5.7, 47.8]; P = 0.004) in non-oxidized glycolytic end products with insulin stimulation in comparison to the lean group (34.2% [24.9, 45.1]; 13.1% [8.6, 16.4], and 2.9% [-4.1, 12.2], respectively). These obesity-related alterations in glucose partitioning appeared to be linked with reduced TCA cycle flux, as 2-[14C]-pyruvate oxidation (358.4 pmol/mg protein/min [303.7, 432.9] vs. lean 439.2 pmol/mg protein/min [393.6, 463.1]; P = 0.013) along with several TCA cycle intermediates, were suppressed in the skeletal muscle of severely obese individuals. CONCLUSIONS: These data suggest that with severe obesity the partitioning of glucose toward anaerobic glycolysis in response to insulin is a resilient characteristic of human skeletal muscle. This altered glucose partitioning appeared to be due, at least in part, to a reduction in TCA cycle flux.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Ciclo do Ácido Cítrico/fisiologia , Glicogênio/metabolismo , Glicólise/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Obesidade Mórbida/metabolismo , Ácidos Tricarboxílicos/metabolismo , Adulto , Células Cultivadas/fisiologia , Feminino , Humanos , Masculino , Fibras Musculares Esqueléticas/patologia , Obesidade Mórbida/fisiopatologia , Cultura Primária de Células
17.
BMC Anesthesiol ; 19(1): 157, 2019 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-31421685

RESUMO

BACKGROUND: The monitoring of regional cerebral oxygen saturation (SrO2) using near-infrared spectroscopy is useful method to detect cerebral ischemia during. Sevoflurane and propofol decrease cerebral metabolic rate (CMRO2) in a similar manner, but the effects on the cerebral blood flow (CBF) are different. We hypothesized that the effects of sevoflurane and propofol on SrO2 were different in patients with deficits of CBF. This study compared the effect of sevoflurane and propofol on SrO2 of patients undergoing cerebral endarterectomy (CEA). METHOD: Patients undergoing CEA were randomly assigned to the sevoflurane or propofol group (n = 74). The experiment was preceded in 2 stages based on carotid artery clamping. The first stage was from induction of anaesthesia to immediately before clamping of the carotid artery, and the second stage was until the end of the operation after clamping of the carotid artery. Oxygen saturation (SrO2, SpO2), haemodynamic variables (blood pressure, heart rate), respiratory parameters (end-tidal carbon dioxide tension, inspired oxygen tension), concentration of anesthetics, and anesthesia depth (bispectral index score) were recorded. RESULTS: During stage 1 period (before carotid artery clamping), the mean value of the relative changes in SrO2 was higher (P = 0.033) and the maximal decrease in SrO2 was lower in the sevoflurane group compared with the propofol group (P = 0.019) in the contralateral (normal) site. However, there is no difference in ipsilateral site (affected site). SrO2 decreased after carotid artery clamping and increased after declamping, but the difference was not significant between two groups. Changes in mean arterial blood pressure was lower in sevoflurane group than propofol group after the carotid artery declamping (P = 0.048). CONCLUSION: Propofol-remifentanil anesthesia was comparable with sevoflurane-remifentanil anesthesia in an aspect of preserving the SrO2 in patients undergoing carotid endarterectomy. TRIAL REGISTRATION: Clinical Trials.gov identifier: NCT02609087 , retrospectively registered on November 18, 2015.


Assuntos
Circulação Cerebrovascular/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Propofol/efeitos adversos , Sevoflurano/efeitos adversos , Idoso , Anestésicos Inalatórios/efeitos adversos , Anestésicos Intravenosos/efeitos adversos , Endarterectomia das Carótidas/métodos , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Propofol/sangue , Estudos Prospectivos , Respiração/efeitos dos fármacos , Sevoflurano/sangue , Espectroscopia de Luz Próxima ao Infravermelho
18.
BMC Anesthesiol ; 19(1): 3, 2019 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-30611215

RESUMO

BACKGROUND: In intubation using fiberoptic bronchoscope (FOB), partial or complete obstruction of upper airway makes the FOB insertion difficult. Thus, maneuvers to relieve such obstructions are recommended. There have been no studies to determine whether the sniffing or neutral position is superior for this purpose. Therefore, this study was performed to examine the effects of these two positions including vocal cord view. METHODS: Fifty-four patients scheduled to receive general anesthesia by orotracheal intubation were eligible for inclusion in the study with informed consent. After confirmation of proper head positioning depending on the group, the view of the vocal cord was acquired in each position. Images were reviewed using the percentage of glottic opening (POGO) score. RESULTS: A total of 106 images of vocal cords from 53 patients were obtained. The mean of difference of POGO score was 11.09, higher for the neutral position and standard deviation was 23.73 (p = 0.002). Neutral position increased POGO score in 31 patients and decreased POGO score in 13 patients compare to sniffing position (p = 0.017). There were no significant differences between the two head positions with regard to intubation time or degree of convenience during intubation. CONCLUSIONS: Neutral position improved the view of glottic opening than sniffing position during oral fiberoptic intubation. However, there was no difference in the difficulty of tube insertion between the two positions. TRIAL REGISTRATION: Clinical Trials.gov identifier: NCT02931019 , registered on October 12, 2016.


Assuntos
Broncoscopia/métodos , Tecnologia de Fibra Óptica , Intubação Intratraqueal/métodos , Posicionamento do Paciente/métodos , Adulto , Idoso , Anestesia Geral/métodos , Estudos Cross-Over , Glote , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
19.
Int J Cancer ; 142(10): 2163-2174, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29277895

RESUMO

Previous studies have shown that increased levels of chemokine receptor CXCR7 are associated with the increased invasiveness of prostate cancer cells. We now show that CXCR7 expression is upregulated in VCaP and C4-2B cells after enzalutamide (ENZ) treatment. ENZ treatment induced apoptosis (sub-G1) in VCaP and C4-2B cells, and this effect was further increased after combination treatment with ENZ and CCX771, a specific CXCR7 inhibitor. The levels of p-EGFR (Y1068), p-AKT (T308) and VEGFR2 were reduced after ENZ and CCX771 combination treatment compared to single agent treatment. In addition, significantly greater reductions in migration were shown after combination treatment compared to those of single agents or vehicle controls, and importantly, similar reductions in the levels of secreted VEGF were also demonstrated. Orthotopic VCaP xenograft growth and subcutaneous MDA133-4 patient-derived xenograft (PDX) tumor growth was reduced by single agent treatment, but significantly greater suppression was observed in the combination treatment group. Although overall microvessel densities in the tumor tissues were not different among the different treatment groups, a significant reduction in large blood vessels (>100 µm2 ) was observed in tumors following combination treatment. Apoptotic indices in tumor tissues were significantly increased following combination treatment compared with vehicle control-treated tumor tissues. Our results demonstrate that significant tumor suppression mediated by ENZ and CXCR7 combination treatment may be due, in part, to reductions in proangiogenic signaling and in the formation of large blood vessels in prostate cancer tumors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Receptores CXCR/antagonistas & inibidores , Animais , Benzamidas , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Nitrilas , Feniltioidantoína/administração & dosagem , Feniltioidantoína/análogos & derivados , Neoplasias de Próstata Resistentes à Castração/irrigação sanguínea , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores CXCR/biossíntese , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Rapid Commun Mass Spectrom ; 32(21): 1843-1850, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30074644

RESUMO

RATIONALE: While global pork production has grown exponentially in recent decades to 109 Mt in 2010, methods aimed at verifying the geographic origin of pork products have yet to be thoroughly investigated. Here, we analyzed pork samples available in South Korea in order to discriminate their geographic origin. METHODS: A total of the 37 pork samples originated from South Korea and other countries (Denmark, Germany, France, Spain, Canada and Mexico) were collected in order to classify their geographic origins using multi-isotope ratios, such as δ18 O, δ2 H, δ13 C, δ15 N values measured by IRMS, 87 Sr/86 Sr ratios measured by MC-ICP-MS, and multivariate statistical approaches. RESULTS: There is a wide range of 87 Sr/86 Sr ratios in the pork samples, varying from 0.70779 to 0.71245, due to the lithology where the pork was raised. Canadian samples displayed the lowest δ18 O and δ2 H values mainly due to the latitude effect. Furthermore, the δ13 C values of European and Canadian samples were lower than those of Korean and Mexican samples, depending on whether the feed was composed of either C3 or C4 plants. The δ15 N values of the European and Canadian samples were much higher than those of the other samples, possibly resulting from the δ15 N values of the feed. CONCLUSIONS: While differences in pork samples were observed that depended on geographic origin, this study suggests that more detailed investigations are needed to validate whether a combination of multi-isotope and multivariate statistical approaches is a valid method for determining the geographic origin of pork.

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