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1.
Sensors (Basel) ; 24(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38203132

RESUMO

Respirometric microbial assays are gaining popularity, but their uptake is limited by the availability of optimal O2 sensing materials and the challenge of validating assays with complex real samples. We conducted a comparative evaluation of four different O2-sensing probes based on Pt-porphyrin phosphors in respirometric bacterial assays performed on standard time-resolved fluorescence reader. The macromolecular MitoXpress, nanoparticle NanO2 and small molecule PtGlc4 and PtPEG4 probes were assessed with E. coli cells in five growth media: nutrient broth (NB), McConkey (MC), Rapid Coliform ChromoSelect (RCC), M-Lauryl lauryl sulfate (MLS), and Minerals-Modified Glutamate (MMG) media. Respiration profiles of the cells were recorded and analyzed, along with densitometry profiles and quenching studies of individual media components. This revealed several limiting factors and interferences impacting assay performance, which include probe quenched lifetime, instrument temporal resolution, inner filter effects (mainly by indicator dyes), probe binding to lipophilic components, and dynamic and static quenching by media components. The study allowed for the ranking of the probes based on their ruggedness, resilience to interferences and overall performance in respirometric bacterial assays. The 'shielded' probe NanO2 outperformed the established MitoXpress probe and the small molecule probes PtGlc4 and PtPEG4.


Assuntos
Bioensaio , Escherichia coli , Transporte Biológico , Ácido Glutâmico , Oxigênio
2.
Artigo em Inglês | MEDLINE | ID: mdl-38197701

RESUMO

White adipose tissue (WAT) controls energy storage, expenditure, and endocrine function. Rho-kinase (ROCK) is related to impaired thermogenesis, downregulation of preadipocyte differentiation, and adipokine production. Furthermore, WAT ROCK responds to metabolic stress from high-fat diets or diabetes. However, ROCK distribution in adipose depots and its response to aging and sex remain unclear. Thus, we aim to investigate ROCK function in adipose tissue of rodent and human in response to aging and sex. We observed specific differences in the ROCK1/2 distribution in inguinal WAT (ingWAT), perigonadal WAT (pgWAT), and brown adipose tissue of male and female rodents. However, ROCK2 expression was lower in female ingWAT compared with males, a fact that was not observed in the other depots. In the pgWAT and ingWAT of male and female rodents, ROCK activity increased during development. Moreover, middle-aged female rodents and humans showed downregulation in ROCK activity after acute physical exercise. Interestingly, ROCK levels were associated with several inflammatory markers both in rats and humans WAT (Nfkb1, Tnf, Il1b, Il6, and Mcp1). Induction of cell senescence by etoposide elevates ROCK activity in human preadipocytes; however, silencing ROCK1/2 demonstrates improvement in the inflammatory and cell senescence state. Using public databases, several pathways were strongly associated with ROCK modulation in WAT. In summary, WAT ROCK increases with development in association with inflammatory markers. Further, ROCK activity was attenuated by acute physical exercise, implicating it as a possible therapeutic target for metabolism improvement mediated by adipose tissue inflammatory state changes.


Assuntos
Roedores , Quinases Associadas a rho , Humanos , Ratos , Masculino , Feminino , Animais , Pessoa de Meia-Idade , Quinases Associadas a rho/fisiologia , Obesidade/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Envelhecimento , Tecido Adiposo
3.
Proc Natl Acad Sci U S A ; 120(52): e2312666120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38127985

RESUMO

AGPAT2 (1-acyl-sn-glycerol-3-phosphate-acyltransferase-2) converts lysophosphatidic acid (LPA) into phosphatidic acid (PA), and mutations of the AGPAT2 gene cause the most common form of congenital generalized lipodystrophy which leads to steatohepatitis. The underlying mechanism by which AGPAT2 deficiency leads to lipodystrophy and steatohepatitis has not been elucidated. We addressed this question using an antisense oligonucleotide (ASO) to knockdown expression of Agpat2 in the liver and white adipose tissue (WAT) of adult male Sprague-Dawley rats. Agpat2 ASO treatment induced lipodystrophy and inflammation in WAT and the liver, which was associated with increased LPA content in both tissues, whereas PA content was unchanged. We found that a controlled-release mitochondrial protonophore (CRMP) prevented LPA accumulation and inflammation in WAT whereas an ASO against glycerol-3-phosphate acyltransferase, mitochondrial (Gpam) prevented LPA content and inflammation in the liver in Agpat2 ASO-treated rats. In addition, we show that overnutrition, due to high sucrose feeding, resulted in increased hepatic LPA content and increased activated macrophage content which were both abrogated with Gpam ASO treatment. Taken together, these data identify LPA as a key mediator of liver and WAT inflammation and lipodystrophy due to AGPAT2 deficiency as well as liver inflammation due to overnutrition and identify LPA as a potential therapeutic target to ameliorate these conditions.


Assuntos
Fígado Gorduroso , Lipodistrofia , Hipernutrição , Masculino , Ratos , Animais , Aciltransferases/metabolismo , Glicerol , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , 1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , Ratos Sprague-Dawley , Lipodistrofia/genética , Tecido Adiposo Branco/metabolismo , Ácidos Fosfatídicos , Inflamação , Fosfatos
4.
Diabetes ; 72(12): 1781-1794, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37725942

RESUMO

Insulin activates insulin receptor (IR) signaling and subsequently triggers IR endocytosis to attenuate signaling. Cell division regulators MAD2, BUBR1, and p31comet promote IR endocytosis on insulin stimulation. Here, we show that genetic ablation of the IR-MAD2 interaction in mice delays IR endocytosis, increases IR levels, and prolongs insulin action at the cell surface. This in turn causes a defect in insulin clearance and increases circulating insulin levels, unexpectedly increasing glucagon levels, which alters glucose metabolism modestly. Disruption of the IR-MAD2 interaction increases serum fatty acid concentrations and hepatic fat accumulation in fasted male mice. Furthermore, disruption of the IR-MAD2 interaction distinctly changes metabolic and transcriptomic profiles in the liver and adipose tissues. Our findings establish the function of cell division regulators in insulin signaling and provide insights into the metabolic functions of IR endocytosis. ARTICLE HIGHLIGHTS: The physiological role of IR endocytosis in insulin sensitivity remains unclear. Disruption of the IR-MAD2 interaction delays IR endocytosis and prolongs insulin signaling. IR-MAD2 controls insulin clearance and glucose metabolism. IR-MAD2 maintains energy homeostasis.


Assuntos
Resistência à Insulina , Receptor de Insulina , Animais , Masculino , Camundongos , Endocitose , Glucose/metabolismo , Homeostase , Insulina/metabolismo , Fígado/metabolismo , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Proteínas Mad2/metabolismo
5.
Am J Physiol Endocrinol Metab ; 325(5): E513-E528, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37755454

RESUMO

Nonalcoholic fatty liver disease (NAFLD), a condition characterized by the accumulation of fat in the liver, is estimated to be the most common liver disease worldwide. Obesity is a major risk factor and contributor, and, accordingly, weight loss can improve NAFLD. Previous studies in preclinical models of diet-induced obesity and fatty liver disease have shown the independent benefits of resistance exercise training (RT) and time-restricted feeding (TRF) in preventing weight gain and hepatic build-up of fat. Here, we tested the combined effect of TRF and RT on obesity and NAFLD in mice fed a high-fat diet. Our results showed that both TRF-8-h food access in the active phase-and RT-consisting of three weekly sessions of ladder climbing-attenuated body weight gain, improved glycemic homeostasis, and decreased the accumulation of lipids in the liver. TRF combined with RT improved the respiratory exchange rate, energy expenditure, and mitochondrial respiration in the liver. Furthermore, gene expression analysis in the liver revealed lower mRNA expression of lipogenesis and inflammation genes along with increased mRNA of fatty acid oxidation genes in the TRF + RT group. Importantly, combined TRF + RT was shown to be more efficient in preventing obesity and metabolic disorders. In conclusion, TRF and RT exert complementary actions compared with isolated interventions, with significant effects on metabolic disorders and NAFLD in mice.NEW & NOTEWORTHY Whether time-restricted feeding (TRF) combined with resistance exercise training (RT) may be more efficient compared with these interventions alone is still unclear. We show that when combined with RT, TRF provided additional benefits, being more effective in increasing energy expenditure, preventing weight gain, and regulating glycemic homeostasis than each intervention alone. Thus, our results demonstrate that TRF and RT have complementary actions on some synergistic pathways that prevented obesity and hepatic liver accumulation.


Assuntos
Doenças Metabólicas , Hepatopatia Gordurosa não Alcoólica , Treinamento Resistido , Camundongos , Animais , Humanos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Metabolismo dos Lipídeos , Dieta Hiperlipídica/efeitos adversos , Obesidade/metabolismo , Fígado/metabolismo , Aumento de Peso , Doenças Metabólicas/metabolismo , RNA Mensageiro/metabolismo , Camundongos Endogâmicos C57BL
6.
Am J Physiol Endocrinol Metab ; 325(4): E363-E375, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37646579

RESUMO

Cancer-related fatigue (CRF) is one of the most common complications in patients with multiple cancer types and severely affects patients' quality of life. However, there have only been single symptom-relieving adjuvant therapies but no effective pharmaceutical treatment for the CRF syndrome. Dichloroacetate (DCA), a small molecule inhibitor of pyruvate dehydrogenase kinase, has been tested as a potential therapy to slow tumor growth, based largely on its effects in vitro to halt cell division. We found that although DCA did not affect rates of tumor growth or the efficacy of standard cancer treatment (immunotherapy and chemotherapy) in two murine cancer models, DCA preserved physical function in mice with late-stage tumors by reducing circulating lactate concentrations. In vivo liquid chromatography-mass spectrometry/mass spectrometry studies suggest that DCA treatment may preserve membrane potential, postpone proteolysis, and relieve oxidative stress in muscles of tumor-bearing mice. In all, this study provides evidence for DCA as a novel pharmaceutical treatment to maintain physical function and motivation in murine models of CRF.NEW & NOTEWORTHY We identify a new metabolic target for cancer-related fatigue, dichloroacetate (DCA). They demonstrate that in mice, DCA preserves physical function and protects against the detrimental effects of cancer treatment by reducing cancer-induced increases in circulating lactate. As DCA is already FDA approved for another indication, these results could be rapidly translated to clinical trials for this condition for which no pharmaceutical therapies exist beyond symptom management.


Assuntos
Ácido Dicloroacético , Fadiga , Melanoma , Qualidade de Vida , Animais , Camundongos , Ácido Dicloroacético/farmacologia , Ácido Dicloroacético/uso terapêutico , Fadiga/tratamento farmacológico , Fadiga/etiologia , Ácido Láctico/metabolismo , Melanoma/complicações
7.
PLoS One ; 18(7): e0286525, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37410734

RESUMO

Reprogramming metabolism is of great therapeutic interest for reducing morbidity and mortality during sepsis-induced critical illness. Disappointing results from randomized controlled trials targeting glutamine and antioxidant metabolism in patients with sepsis have begged a deeper understanding of the tissue-specific metabolic response to sepsis. The current study sought to fill this gap. We analyzed skeletal muscle transcriptomics of critically ill patients, versus elective surgical controls, which revealed reduced expression of genes involved in mitochondrial metabolism and electron transport, with increases in glutathione cycling, glutamine, branched chain, and aromatic amino acid transport. We then performed untargeted metabolomics and 13C isotope tracing to analyze systemic and tissue specific metabolic phenotyping in a murine polymicrobial sepsis model. We found an increased number of correlations between the metabolomes of liver, kidney, and spleen, with loss of correlations between the heart and quadriceps and all other organs, pointing to a shared metabolic signature within vital abdominal organs, and unique metabolic signatures for muscles during sepsis. A lowered GSH:GSSG and elevated AMP:ATP ratio in the liver underlie the significant upregulation of isotopically labeled glutamine's contribution to TCA cycle anaplerosis and glutamine-derived glutathione biosynthesis; meanwhile, the skeletal muscle and spleen were the only organs where glutamine's contribution to the TCA cycle was significantly suppressed. These results highlight tissue-specific mitochondrial reprogramming to support liver energetic demands and antioxidant synthesis, rather than global mitochondrial dysfunction, as a metabolic consequence of sepsis.


Assuntos
Glutamina , Sepse , Humanos , Camundongos , Animais , Glutamina/metabolismo , Antioxidantes/metabolismo , Glutationa/metabolismo , Músculo Esquelético/metabolismo , Sepse/metabolismo
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 300: 122915, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37269659

RESUMO

A nanosensor based on magnetic core-shell nanoparticles functionalized with rhodamine derivative, N-(3-carboxy)acryloyl rhodamine B hydrazide (RhBCARB), using (3-aminopropyl)triethoxysilane (APTES) as a linker, has been synthesized for detection of Cu(II) ions in water. The magnetic nanoparticle and the modified rhodamine were fully characterized, showing a strong orange emission sensitive to Cu(II) ions. The sensor shows a linear response from 10 to 90 µg L-1, detection limit of 3 µg L-1 and no interference of Ni(II), Co(II), Cd(II), Zn(II), Pb(II), Hg(II) and Fe(II) ions. The nanosensor performance is similar to those described in the literature, being a viable option for the determination of Cu(II) ions in natural waters. In addition, the magnetic sensor can be easily removed from the reaction medium with the aid of a magnet and its signal recovered in acidic solution, allowing its reuse in subsequent analysis.


Assuntos
Cobre , Corantes Fluorescentes , Cobre/análise , Rodaminas , Íons , Fenômenos Magnéticos
9.
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
10.
Proc Natl Acad Sci U S A ; 120(4): e2217543120, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36669104

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, in which prognosis is determined by liver fibrosis. A common variant in hydroxysteroid 17-beta dehydrogenase 13 (HSD17B13, rs72613567-A) is associated with a reduced risk of fibrosis in NAFLD, but the underlying mechanism(s) remains unclear. We investigated the effects of this variant in the human liver and in Hsd17b13 knockdown in mice by using a state-of-the-art metabolomics approach. We demonstrate that protection against liver fibrosis conferred by the HSD17B13 rs72613567-A variant in humans and by the Hsd17b13 knockdown in mice is associated with decreased pyrimidine catabolism at the level of dihydropyrimidine dehydrogenase. Furthermore, we show that hepatic pyrimidines are depleted in two distinct mouse models of NAFLD and that inhibition of pyrimidine catabolism by gimeracil phenocopies the HSD17B13-induced protection against liver fibrosis. Our data suggest pyrimidine catabolism as a therapeutic target against the development of liver fibrosis in NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Fígado/metabolismo , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Pirimidinas/farmacologia , Pirimidinas/metabolismo
11.
J Nutr Biochem ; 114: 109270, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36706930

RESUMO

It is known that long-term high-fat diet (HF) feeding drastically affects the adipose tissue, contributing to metabolic disorders. Recently, short-term HF consumption was shown to affect different neuronal signaling pathways. Thus, we aimed to evaluate the inflammatory effects of a short-term HF and whether a diet containing omega-3 fatty acid fats from flaxseed oil (FS) has protective effects. Mice were divided into three groups for 3 d, according to their diets: Control group (CT), HF, or FS for 3 d. Lipid profiles were assessed through mass spectrometry and inflammatory markers by RT-qPCR and Western blotting. After short-term HF, mice increased food intake, body weight, adiposity, and fasting glucose. Increased mRNA content of Ccl2 and Tnf was demonstrated in the HF compared to CT in mesenteric adipose tissue. In the liver, TNFα protein was higher in the HF group than in CT, followed by a decreased polyunsaturated fatty acids tissue incorporation in HF. On the other hand, the consumption of FS reduced food intake and fasting glucose, as well as increased omega-3 fatty acid incorporation in MAT and the liver. However, short-term FS was insufficient to control the early inflammation triggered by HF in MAT and the liver. These data demonstrated that a 3-d HF diet is enough to damage glucose homeostasis and trigger inflammation. In contrast, short-term FS protects against increased food intake and fasting glucose but not inflammation in mice.


Assuntos
Dieta Hiperlipídica , Ácidos Graxos Ômega-3 , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Óleo de Semente do Linho/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Ômega-3/metabolismo , Inflamação/metabolismo , Tecido Adiposo/metabolismo , Glucose/metabolismo , Camundongos Endogâmicos C57BL
12.
Cell Metab ; 35(1): 212-226.e4, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36516861

RESUMO

The mammalian succinate dehydrogenase (SDH) complex has recently been shown as capable of operating bidirectionally. Here, we develop a method (Q-Flux) capable of measuring absolute rates of both forward (VSDH(F)) and reverse (VSDH(R)) flux through SDH in vivo while also deconvoluting the amount of glucose derived from four discreet carbon sources in the liver. In validation studies, a mitochondrial uncoupler increased net SDH flux by >100% in awake rodents but also increased SDH cycling. During hyperglucagonemia, attenuated pyruvate cycling enhances phosphoenolpyruvate carboxykinase efficiency to drive increased gluconeogenesis, which is complemented by increased glutaminase (GLS) flux, methylmalonyl-CoA mutase (MUT) flux, and glycerol conversion to glucose. During hyperinsulinemic-euglycemic clamp, both pyruvate carboxylase and GLS are suppressed, while VSDH(R) is increased. Unstimulated MUT is a minor anaplerotic reaction but is readily induced by small amounts of propionate, which elicits glucagon-like metabolic rewiring. Taken together, Q-Flux yields a comprehensive picture of hepatic mitochondrial metabolism and should be broadly useful to researchers.


Assuntos
Metilmalonil-CoA Mutase , Succinato Desidrogenase , Animais , Glucose/metabolismo , Glutaminase/metabolismo , Fígado/metabolismo , Metilmalonil-CoA Mutase/metabolismo , Proteínas/metabolismo , Ácido Pirúvico/metabolismo , Succinato Desidrogenase/metabolismo , Roedores
13.
Cell Biochem Funct ; 41(1): 128-137, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36515301

RESUMO

Dysfunction of the adipose tissue metabolism is considered as a significant hallmark of aging. It has been proposed that α-ß hydrolase domain containing 5 (ABHD5) plays a critical role in the control of lipolysis. However, the role of ABHD5 in the control of lipolysis during aging or exercise is unknown. Here we combined the experimental mouse model with transcriptomic analyzes by using murine and human databases to explore the role of ABHD5 in the adipose tissue during aging and in response to exercise. Transcriptomic data revealed a downregulation of Abhd5 messenger RNA levels in the subcutaneous white adipose tissue (scWAT) over time in individuals from 20 to 69 years old. Aged mice displayed dramatic reduction of ABHD5 protein content and lipolytic-related proteins in the scWAT. Interestingly, 4 weeks of high-intensity interval training increased ABHD5 protein level and restored the lipolytic pathway in the scWAT of aged mice. Altogether, our findings demonstrated that aging affects ABHD5 content in the adipose tissue of mice and humans. Conversely, exercise increases ABHD5 activity, recovering the lipolytic activity in aged mice.


Assuntos
1-Acilglicerol-3-Fosfato O-Aciltransferase , Tecido Adiposo , Envelhecimento , Exercício Físico , Lipólise , Adulto , Idoso , Animais , Humanos , Camundongos , Pessoa de Meia-Idade , Adulto Jovem , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , 1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , Tecido Adiposo/enzimologia , Envelhecimento/metabolismo , Hidrolases/genética , Hidrolases/metabolismo
14.
Diabetologia ; 66(3): 567-578, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36456864

RESUMO

AIMS/HYPOTHESIS: Athletes exhibit increased muscle insulin sensitivity, despite increased intramuscular triacylglycerol content. This phenomenon has been coined the 'athlete's paradox' and is poorly understood. Recent findings suggest that the subcellular distribution of sn-1,2-diacylglycerols (DAGs) in the plasma membrane leading to activation of novel protein kinase Cs (PKCs) is a crucial pathway to inducing insulin resistance. Here, we hypothesised that regular aerobic exercise would preserve muscle insulin sensitivity by preventing increases in plasma membrane sn-1,2-DAGs and activation of PKCε and PKCθ despite promoting increases in muscle triacylglycerol content. METHODS: C57BL/6J mice were allocated to three groups (regular chow feeding [RC]; high-fat diet feeding [HFD]; RC feeding and running wheel exercise [RC-EXE]). We used a novel LC-MS/MS/cellular fractionation method to assess DAG stereoisomers in five subcellular compartments (plasma membrane [PM], endoplasmic reticulum, mitochondria, lipid droplets and cytosol) in the skeletal muscle. RESULTS: We found that the HFD group had a greater content of sn-DAGs and ceramides in multiple subcellular compartments compared with the RC mice, which was associated with an increase in PKCε and PKCθ translocation. However, the RC-EXE mice showed, of particular note, a reduction in PM sn-1,2-DAG and ceramide content when compared with HFD mice. Consistent with the PM sn-1,2-DAG-novel PKC hypothesis, we observed an increase in phosphorylation of threonine1150 on the insulin receptor kinase (IRKT1150), and reductions in insulin-stimulated IRKY1162 phosphorylation and IRS-1-associated phosphoinositide 3-kinase activity in HFD compared with RC and RC-EXE mice, which are sites of PKCε and PKCθ action, respectively. CONCLUSIONS/INTERPRETATION: These results demonstrate that lower PKCθ/PKCε activity and sn-1,2-DAG content, especially in the PM compartment, can explain the preserved muscle insulin sensitivity in RC-EXE mice.


Assuntos
Resistência à Insulina , Camundongos , Animais , Resistência à Insulina/fisiologia , Proteína Quinase C-theta/metabolismo , Proteína Quinase C-épsilon/metabolismo , Cromatografia Líquida , Fosfatidilinositol 3-Quinases/metabolismo , Camundongos Endogâmicos C57BL , Espectrometria de Massas em Tandem , Insulina/metabolismo , Músculo Esquelético/metabolismo , Triglicerídeos/metabolismo , Ceramidas/metabolismo
15.
Bioconjug Chem ; 33(11): 2161-2169, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36289566

RESUMO

Biological applications of phosphorescent probes for sensing molecular oxygen (O2) and bioimaging have gained popularity, but their choice is rather limited. We describe a family of new heterosubstituted phosphorescent bioprobes based on the Pt(II)-tetrakis(pentafluorophenyl)porphyrin (PtPFPP) dye. The probes are produced by simple click modification of its para-fluorine atoms with thiols, such as 1/2-thio-glucose, thio-poly(ethylene glycol) (PEG), or cysteamine. The probes were designed to have one cell-targeting moiety and three polar moieties forming a hydrophilic shell. Their chemical synthesis and purification were optimized to produce high reaction yields and easy scale-up. The ability to perform as cell-permeable or -impermeable probes was tuned by the polarity and molecular charge of the bioconjugate. The new PtPFPP derivatives were characterized for their spectral properties and cell-penetrating ability in the experiments with mammalian cell cultures, using a time-resolved fluorescence reader and PLIM imaging detection. Structure-activity relationships were established. Thus, the tri- and tetra-PEGylated structures showed low cell internalization allowing their use as extracellular probes, while cysteamine derivatives performed as efficient intracellular probes. No significant cytotoxicity was observed for all of the probes under the experimental conditions used.


Assuntos
Técnicas Biossensoriais , Porfirinas , Animais , Cisteamina , Porfirinas/química , Oxigênio , Técnicas Biossensoriais/métodos , Relação Estrutura-Atividade , Mamíferos
16.
Proc Natl Acad Sci U S A ; 119(10): e2122287119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35238637

RESUMO

SignificanceMetformin is the most commonly prescribed drug for the treatment of type 2 diabetes mellitus, yet the mechanism by which it lowers plasma glucose concentrations has remained elusive. Most studies to date have attributed metformin's glucose-lowering effects to inhibition of complex I activity. Contrary to this hypothesis, we show that inhibition of complex I activity in vitro and in vivo does not reduce plasma glucose concentrations or inhibit hepatic gluconeogenesis. We go on to show that metformin, and the related guanides/biguanides, phenformin and galegine, inhibit complex IV activity at clinically relevant concentrations, which, in turn, results in inhibition of glycerol-3-phosphate dehydrogenase activity, increased cytosolic redox, and selective inhibition of glycerol-derived hepatic gluconeogenesis both in vitro and in vivo.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Gluconeogênese , Guanidinas/farmacologia , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Fenformin/farmacologia , Animais , Glucose/metabolismo , Glicerol/metabolismo , Glicerolfosfato Desidrogenase/antagonistas & inibidores , Fígado/efeitos dos fármacos , Fígado/metabolismo , Oxirredução , Piridinas/farmacologia
17.
Nursing (Ed. bras., Impr.) ; 25(285): 7282-7298, fev.2022.
Artigo em Inglês, Português | LILACS, BDENF - Enfermagem | ID: biblio-1371987

RESUMO

Objetivo: descrever a experiência da Supervisão de Enfermagem em um hospital universitário no município do Rio de Janeiro, frente à pandemia da covid-19. Método: estudo qualitativo, descritivo, tipo relato de experiência, baseado na vivência dos autores e na análise de documentos entre março e dezembro de 2020. Resultados: a pandemia acrescentou desafios ao trabalho da supervisão, além daqueles inerentes a instituição. O aumento e a especificidade da demanda provocaram um refinamento na atuação do grupo no intuito de otimizar processos e servindo como elo entre pacientes, equipe e instituição. Conclusão: é fundamental dar voz ao corpo da Enfermagem e à clientela, para a construção de uma prática ética, ancorada na ciência, contextualizada nas esferas ­ social, histórica e política, com um olhar atento ao ambiente de trabalho, tratando com respeito os problemas do cotidiano hospitalar, tangenciado pela pandemia de covid-19(AU)


Objective: to describe the experience of Nursing Supervision in a university hospital in the city of Rio de Janeiro, facing the COVID-19 pandemic. Method: qualitative, descriptive study, experience report type, based on the authors' experience and on the analysis of documents between March and December 2020. Results: the pandemic added challenges to the work of supervision, in addition to those inherent to the institution. The increase and specificity of demand led to a refinement in the group's performance in order to optimize processes and serving as a link between patients, staff and institution. Conclusion: it is essential to give a voice to the Nursing body and the clientele, for the construction of an ethical practice, anchored in science, contextualized in the social, historical and political spheres, with an attentive look at the work environment, dealing with problems with respect hospital routine, affected by the COVID-19 pandemic.(AU)


Objetivo: describir la experiencia de Supervisión de Enfermería en un hospital universitario de la ciudad de Río de Janeiro, frente a la pandemia COVID-19. Método: estudio cualitativo, descriptivo, tipo relato de experiencia, basado en la experiencia de los autores y en el análisis de documentos entre marzo y diciembre de 2020. Resultados: la pandemia agregó desafíos a la supervisión, además de los inherentes a la institución. El aumento y la especificidad de la demanda han perfeccionado el desempeño del grupo para optimizar los procesos y servir de vínculo entre los pacientes, el personal y la institución. Conclusión: es fundamental dar voz al cuerpo de Enfermería y a la clientela, construyendo una práctica ética, anclada en la ciencia, contextualizada en los ámbitos social, histórico y político, con una mirada atenta al entorno laboral, abordando la problemática de la vida diaria hospitalaria con respeto, tocada por la pandemia COVID-19(AU)


Assuntos
Supervisão de Enfermagem , Governança Compartilhada de Enfermagem , COVID-19
18.
J Physiol ; 600(4): 797-813, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33450053

RESUMO

KEY POINTS: Time-restricted feeding (TRF, in which energy intake is restricted to 8 h/day during the dark phase) alone or combined with aerobic exercise (AE) training can prevent weight gain and metabolic disorders in Swiss mice fed a high-fat diet. The benefits of TRF combined with AE are associated with improved hepatic metabolism and decreased hepatic lipid accumulation. TRF combined with AE training increased fatty acid oxidation and decreased expression of lipogenic and gluconeogenic genes in the liver of young male Swiss mice. TRF combined with AE training attenuated the detrimental effects of high-fat diet feeding on the insulin signalling pathway in the liver. ABSTRACT: Time-restricted feeding (TRF) or physical exercise have been shown to be efficient in the prevention and treatment of metabolic disorders; however, the additive effects of TRF combined with aerobic exercise (AE) training on liver metabolism have not been widely explored. In this study TRF (8 h in the active phase) and TRF combined with AE (TRF+Exe) were compared in male Swiss mice fed a high-fat diet, with evaluation of the effects on insulin sensitivity and expression of hepatic genes involved in fatty acid oxidation, lipogenesis and gluconeogenesis. As in previous reports, we show that TRF alone (eating only between zeitgeber time 16 and 0) was sufficient to reduce weight and adiposity gain, increase fatty acid oxidation and decrease lipogenesis genes in the liver. In addition, we show that mice of the TRF+Exe group showed additional adaptations such as increased oxygen consumption ( V̇O2${\dot V_{{{\rm{O}}_{\rm{2}}}}}$ ), carbon dioxide production ( V̇CO2${\dot V_{{\rm{C}}{{\rm{O}}_{\rm{2}}}}}$ ) and production of ketone bodies (ß-hydroxybutyrate). Also, TRF+Exe attenuated the negative effects of high-fat diet feeding on the insulin signalling pathway (insulin receptor, insulin receptor substrate, Akt), and led to increased fatty acid oxidation (Ppara, Cpt1a) and decreased gluconeogenic (Fbp1, Pck1, Pgc1a) and lipogenic (Srebp1c, Cd36) gene expression in the liver. These molecular results were accompanied by increased glucose metabolism, lower serum triglycerides and reduced hepatic lipid content in the TRF+Exe group. The data presented in this study show that TRF alone has benefits but TRF+Exe has additive benefits and can mitigate the harmful effects of consuming a high-fat diet on body adiposity, liver metabolism and glycaemic homeostasis in young male Swiss mice.


Assuntos
Resistência à Insulina , Doenças Metabólicas , Animais , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Masculino , Doenças Metabólicas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Aumento de Peso
19.
Rev. bras. enferm ; 75(3): e20201323, 2022. tab
Artigo em Inglês | LILACS-Express | LILACS, BDENF - Enfermagem | ID: biblio-1347199

RESUMO

ABSTRACT Objectives: to understand the meanings and significance attributed by people with HIV/aids to the process of living with this virus/disease. Methods: qualitative and exploratory study, carried out in Rio de Janeiro, Brazil. The Grounded Theory and the Symbolic Interactionism were used. Data were collected in a semistructured interview and through non-participant observation, from August 2017 to May 2018. 29 patients participated. Results: living with HIV/AIDS is a social phenomenon in which it is not possible to disconnect the process of adapting to the disease from the social relations one (re)constructs during life. It also involves stigmatization, rejection, and isolation. Final Considerations: understanding the meanings of this process is a positive influence for proactive behavior and resilience, not only in regard to the care concerning the presence of the virus and the uninterrupted need to adhere to medication, but also in the way to deal with the social values that reproduce previous models, which, in turn, can help improve self-knowledge.


RESUMEN Objetivos: comprender los significados y sentidos atribuidos por personas con VIH/SIDA sobre el proceso de convivir con ese virus/enfermedad. Métodos: estudio cualitativo, exploratorio, realizado en Rio de Janeiro, Brasil. Utilizado la Teoría Fundamentada en los Datos e Interaccionismo Simbólico. Datos recolectados por entrevista semiestructurada y observación no participante, entre agosto de 2017 y mayo de 2018. Participaron 29 pacientes. Resultados: convivir con VIH/SIDA es un fenómeno social, en que no hay posibilidad de desvincular el proceso de adaptación a la enfermedad de las relaciones sociales (re)construidas durante la vida, aún acompañado de estigmatización, rechazo y aislamiento. Consideraciones Finales: comprender los significados de ese proceso de convivencia favorece el comportamiento proactivo y resiliencia, no solo cuanto a cuidados delante la presencia del virus y la necesidad continua de adherir a medicamentos, pero también al lidiar con los valores sociales que reproducen modelos, los cuales, en contrapartida, pueden ayudar en el autoconocimiento.


RESUMO Objetivos: compreender os significados e sentidos atribuídos por pessoas com HIV/aids sobre o processo de conviver com este vírus/doença. Métodos: estudo qualitativo, exploratório, realizado no Rio de Janeiro, Brasil. Utilizou-se a Teoria Fundamentada nos Dados e o Interacionismo Simbólico. Os dados foram coletados por entrevista semiestruturada e observação não participante, entre agosto de 2017 e maio de 2018. Participaram 29 pacientes. Resultados: conviver com o HIV/aids é um fenômeno social, onde não há possibilidade de desvincular o processo de adaptação à doença das relações sociais (re)construídas ao longo da vida, ainda acompanhado de estigmatização, rejeição e isolamento. Considerações Finais: compreender os significados deste processo de convivência favorece o comportamento proativo e a resiliência, não só em relação aos cuidados diante da presença do vírus e à necessidade ininterrupta de aderir aos medicamentos, mas também ao lidar com os valores sociais que reproduzem modelos, que em contrapartida, podem ajudar no autoconhecimento.

20.
Rev Bras Enferm ; 75(3): e20201323, 2021.
Artigo em Inglês, Português | MEDLINE | ID: mdl-34706046

RESUMO

OBJECTIVES: to understand the meanings and significance attributed by people with HIV/aids to the process of living with this virus/disease. METHODS: qualitative and exploratory study, carried out in Rio de Janeiro, Brazil. The Grounded Theory and the Symbolic Interactionism were used. Data were collected in a semistructured interview and through non-participant observation, from August 2017 to May 2018. 29 patients participated. RESULTS: living with HIV/AIDS is a social phenomenon in which it is not possible to disconnect the process of adapting to the disease from the social relations one (re)constructs during life. It also involves stigmatization, rejection, and isolation. FINAL CONSIDERATIONS: understanding the meanings of this process is a positive influence for proactive behavior and resilience, not only in regard to the care concerning the presence of the virus and the uninterrupted need to adhere to medication, but also in the way to deal with the social values that reproduce previous models, which, in turn, can help improve self-knowledge.


Assuntos
Infecções por HIV , Brasil , Teoria Fundamentada , Infecções por HIV/complicações , Humanos , Autoimagem , Estereotipagem
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