Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Mediators Inflamm ; 2019: 1491083, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30983877

RESUMO

AIM: The development of type 2 diabetes (T2DM) is associated with disturbances of immune status that may be reflected by alterations of the profile of circulating immune cells. In order to study whether there exists genetic predisposition to these alterations, we investigated the relative content of circulating monocyte and lymphocyte subpopulations at fasting condition and upon stimulation by short-term hyperinsulinemia in nondiabetic first-degree relatives (FDR) of T2DM patients and in control subjects. MATERIALS AND METHODS: 19 nondiabetic (FDR) and 19 control subjects without a family history of diabetes (all men) matched for age and BMI underwent 2-hour hyperinsulinemic-euglycemic clamp. Blood samples taken before and at the end of the clamp were used for the flow cytometry analysis of lymphocyte and monocyte populations and for the assessment of cytokine levels. RESULTS: At fasting conditions, FDR showed a higher CD4/CD8 ratio of peripheral lymphocytes, a higher percentage of Th17 lymphocytes, and a lower content of intermediate monocytes when compared to controls. The CD4/CD8 ratio correlated with fat mass, insulin, and HOMA-IR in the entire group of subjects. Hyperinsulinemia decreased a relative content of peripheral CD4+ and increased a relative content of CD8+ T lymphocytes, thus decreasing the CD4/CD8 ratio by 18-22% in both groups of subjects. In FDR but not in controls, the decrease of CD4+ T lymphocyte content was partially based on the decrease of TH2 and TH17 lymphocyte subpopulations. In control subjects but not in FDR, the number of intermediate monocytes has declined in response to hyperinsulinemia. CONCLUSION: The alterations of the CD4/CD8 lymphocyte ratio, relative content of TH17 cells, and intermediate monocytes in FDR are features of genetic predisposition to T2DM and may play a role in pathogenesis of T2DM. Short-term hyperinsulinemia affected mostly the immune cell populations deregulated in FDR subjects, which suggests important interplay between immune system homeostasis and insulin levels.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Jejum/sangue , Hiperinsulinismo/sangue , Subpopulações de Linfócitos/metabolismo , Monócitos/metabolismo , Adulto , Glicemia/metabolismo , Índice de Massa Corporal , Relação CD4-CD8 , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Hiperinsulinismo/metabolismo , Hiperinsulinismo/patologia , Resistência à Insulina/fisiologia , Masculino , Células Th17/metabolismo , Células Th2/metabolismo
2.
Am J Respir Cell Mol Biol ; 55(2): 299-307, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26978122

RESUMO

Obstructive sleep apnea (OSA) is associated with insulin resistance, glucose intolerance, and type 2 diabetes. Causal mechanisms mediating this association are not well defined; however, augmented lipolysis in adipose might be involved. Here, we investigated the effect of acipimox treatment (lipolysis inhibitor) on glucose tolerance and insulin sensitivity in mice exposed to intermittent hypoxia (IH). C57BL6/J mice were exposed for 14 days to IH or control conditions. IH was created by decreasing the fraction of inspired oxygen from 20.9 to 6.5%, 60 times/h. Control exposure was air (fraction of inspired oxygen, 20.9%) delivered at an identical flow rate. Acipimox was provided in drinking water (0.5 g/ml) during exposures. After exposures, intraperitoneal insulin (0.5 IU/kg) and glucose (1 g/kg) tolerance tests were performed, and primary adipocytes were isolated for lipolysis experiments. IH elevated fasting glucose by 51% and worsened glucose tolerance and insulin sensitivity by 33 and 102%, respectively. In parallel, IH increased spontaneous lipolysis by 264%, and reduced epididymal fat mass by 15% and adipocyte size by 8%. Acipimox treatment prevented IH-induced lipolysis and increased epididymal fat mass and adipocyte size by 19 and 10%, respectively. Acipimox fully prevented IH-induced impairments in fasting glycemia, glucose tolerance, and insulin sensitivity. For all reported results, P less than 0.05 was considered significant. Augmented lipolysis contributes to insulin resistance and glucose intolerance observed in mice exposed to IH. Acipimox treatment ameliorated the metabolic consequences of IH and might represent a novel treatment option for patients with obstructive sleep apnea.


Assuntos
Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/patologia , Lipólise , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/patologia , Adipócitos/efeitos dos fármacos , Adipócitos/patologia , Adiposidade/efeitos dos fármacos , Animais , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/genética , Modelos Animais de Doenças , Ácidos Graxos/sangue , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Hipóxia/complicações , Hipóxia/metabolismo , Insulina/metabolismo , Lipólise/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Fenótipo , Pirazinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/genética
3.
Biochem Biophys Res Commun ; 478(2): 727-32, 2016 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-27498031

RESUMO

In-vitro investigation of the effects of hypoxia is limited by physical laws of gas diffusion and cellular O2 consumption, making prolonged exposures to stable O2 concentrations impossible. Using a gas-permeable cultureware, chronic effects of mild and severe hypoxia on triglyceride accumulation, lipid droplet size distribution, spontaneous lipolysis and gene expression of adipocyte-specific markers were assessed. 3T3-L1 cells were differentiated under 20%, 4% or 1% O2 using a gas-permeable cultureware. Triglyceride accumulation, expression of genes characteristic for advanced adipocyte differentiation and involvement of key lipogenesis enzymes were assessed after exposures. Lipogenesis increased by 375% under mild hypoxia, but dropped by 43% in severe hypoxia. Mild, but not severe, hypoxia increased formation of large lipid droplets 6.4 fold and strongly induced gene expression of adipocyte-specific markers. Spontaneous lipolysis increased by 488% in mild, but only by 135% in severe hypoxia. Inhibition of ATP-dependent citrate lyase suppressed hypoxia-induced lipogenesis by 81% and 85%. Activation of HIF inhibited lipogenesis by 59%. Mild, but not severe, hypoxia stimulates lipolysis and promotes adipocyte differentiation, probably through excess of acetyl-CoA originating from tricarboxylic acid cycle independently of HIF activation.


Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Lipólise/efeitos dos fármacos , Oxigênio/farmacologia , Células 3T3-L1 , ATP Citrato (pro-S)-Liase/genética , ATP Citrato (pro-S)-Liase/metabolismo , Acetilcoenzima A/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Adipogenia/genética , Animais , Diferenciação Celular/efeitos dos fármacos , Hipóxia Celular , Ciclo do Ácido Cítrico/efeitos dos fármacos , Ciclo do Ácido Cítrico/genética , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Relação Dose-Resposta a Droga , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Gotículas Lipídicas/química , Gotículas Lipídicas/efeitos dos fármacos , Lipogênese/genética , Lipólise/genética , Camundongos , Perilipina-1/genética , Perilipina-1/metabolismo , Transdução de Sinais , Esterol Esterase/genética , Esterol Esterase/metabolismo , Triglicerídeos/metabolismo
4.
Biochem Biophys Res Commun ; 460(3): 684-90, 2015 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-25813485

RESUMO

BACKGROUND: Adipocytes are cells specialized for storage of neutral lipids. This storage capacity is dependent on lipogenesis and is diminished in obesity. The reason for the decline in lipogenic activity of adipocytes in obesity remains unknown. Recent data show that lipogenesis in liver is regulated by pathways initiated by endoplasmic reticulum stress (ERS). Thus, we aimed at investigating the effect of ERS on lipogenesis in adipose cells. METHODS: Preadipocytes were isolated from subcutaneous abdominal adipose tissue from obese volunteers and in vitro differentiated into adipocytes. ERS was induced pharmacologically by thapsigargin (TG) or tunicamycin (TM). Activation of Unfolded Protein Response pathway (UPR) was monitored on the level of eIF2α phosphorylation and mRNA expression of downstream targets of UPR sensors. Adipogenic and lipogenic capacity was evaluated by Oil Red O staining, measurement of incorporation of radio-labelled glucose or acetic acid into lipids and mRNA analysis of adipogenic/lipogenic markers. RESULTS: Exposition of adipocytes to high doses of TG (100 nM) and TM (1 µg/ml) for 1-24 h enhanced expression of several UPR markers (HSPA5, EDEM1, ATF4, XBP1s) and phosphorylation of eIF2α. This acute ERS substantially inhibited expression of lipogenic genes (DGAT2, FASN, SCD1) and glucose incorporation into lipids. Moreover, chronic exposure of preadipocytes to low dose of TG (2.5 nM) during the early phases of adipogenic conversion of preadipocytes impaired both, lipogenesis and adipogenesis. On the other hand, chronic low ERS had no apparent effect on lipogenesis in mature adipocytes. CONCLUSIONS: Acute ERS weakened a capacity of mature adipocytes to store lipids and chronic ERS diminished adipogenic potential of preadipocytes.


Assuntos
Adipócitos/citologia , Diferenciação Celular , Retículo Endoplasmático/metabolismo , Lipídeos/biossíntese , Estresse Fisiológico , Retículo Endoplasmático/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Humanos , Fosforilação , Tapsigargina/farmacologia , Tunicamicina/farmacologia , Resposta a Proteínas não Dobradas
5.
Br J Nutr ; 112(4): 573-82, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-24870697

RESUMO

The consumption of lipids and simple sugars induces an inflammatory response whose exact molecular trigger remains elusive. The aims of the present study were to investigate (1) whether inflammation induced by a single high-energy, high-fat meal (HFM) is associated with endoplasmic reticulum stress (ERS) in peripheral blood mononuclear cells (PBMC) and (2) whether these inflammatory and ERS responses could be prevented by the chemical chaperone ursodeoxycholic acid (UDCA). A total of ten healthy lean men were recruited to a randomised, blind, cross-over trial. Subjects were given two doses of placebo (lactose) or UDCA before the consumption of a HFM (6151 kJ; 47·4 % lipids). Blood was collected at baseline and 4 h after the HFM challenge. Cell populations and their activation were analysed using flow cytometry, and plasma levels of inflammatory cytokines were assessed by ELISA and Luminex technology. Gene expression levels of inflammatory and ERS markers were analysed in CD14⁺ and CD14⁻ PBMC using quantitative RT-PCR. The HFM induced an increase in the mRNA expression levels of pro-inflammatory cytokines (IL-1ß, 2·1-fold; IL-8, 2·4-fold; TNF-α, 1·4-fold; monocyte chemoattractant protein 1, 2·1-fold) and a decrease in the expression levels of miR181 (0·8-fold) in CD14⁺ monocytes. The HFM challenge did not up-regulate the expression of ERS markers (XBP1, HSPA5, EDEM1, DNAJC3 and ATF4) in either CD14⁺ or CD14⁻ cell populations, except for ATF3 (2·3-fold). The administration of UDCA before the consumption of the HFM did not alter the HFM-induced change in the expression levels of ERS or inflammatory markers. In conclusion, HFM-induced inflammation detectable on the level of gene expression in PBMC was not associated with the concomitant increase in the expression levels of ERS markers and could not be prevented by UDCA.


Assuntos
Imunidade Adaptativa , Dieta Hiperlipídica/efeitos adversos , Estresse do Retículo Endoplasmático , Hiperfagia/imunologia , Imunidade Inata , Leucócitos Mononucleares/imunologia , Refeições , Imunidade Adaptativa/efeitos dos fármacos , Adulto , Anti-Inflamatórios/farmacologia , Biomarcadores/sangue , Biomarcadores/metabolismo , Colagogos e Coleréticos/farmacologia , Estudos Cross-Over , Citocinas/sangue , Citocinas/genética , Citocinas/metabolismo , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ingestão de Energia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hiperfagia/sangue , Hiperfagia/metabolismo , Imunidade Inata/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Receptores de Lipopolissacarídeos/sangue , Receptores de Lipopolissacarídeos/metabolismo , Masculino , MicroRNAs/metabolismo , Período Pós-Prandial , Ácido Ursodesoxicólico/farmacologia
6.
Obesity (Silver Spring) ; 32(3): 547-559, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38221680

RESUMO

OBJECTIVE: This study tested the hypothesis that limited subcutaneous adipose tissue (SAT) expansion represents a primary predisposition to the development of type 2 diabetes mellitus (T2DM), independent of obesity, and identified novel markers of SAT dysfunction in the inheritance of T2DM. METHODS: First-degree relatives (FDR) of T2DM patients (n = 19) and control individuals (n = 19) without obesity (fat mass < 25%) were cross-sectionally compared. Body composition (bioimpedance, computed tomography) and insulin sensitivity (IS; oral glucose tolerance test, clamp) were measured. SAT obtained by needle biopsy was used to analyze adipocyte size, lipidome, mRNA expression, and inflammatory markers. Primary cultures of adipose precursors were analyzed for adipogenic capacity and metabolism. RESULTS: Compared with control individuals, FDR individuals had lower IS and a higher amount of visceral fat. However, SAT-derived adipose precursors did not differ in their ability to proliferate and differentiate or in metabolic parameters (lipolysis, mitochondrial oxidation). In SAT of FDR individuals, lipidomic and mRNA expression analysis revealed accumulation of triglycerides containing polyunsaturated fatty acids and increased mRNA expression of lysyl oxidase (LOX). These parameters correlated with IS, visceral fat accumulation, and mRNA expression of inflammatory and cellular stress genes. CONCLUSIONS: The intrinsic adipogenic potential of SAT is not affected by a family history of T2DM. However, alterations in LOX mRNA and polyunsaturated fatty acids in triacylglycerols are likely related to the risk of developing T2DM independent of obesity.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Estudos Transversais , Gordura Subcutânea/metabolismo , Resistência à Insulina/genética , Obesidade/genética , Obesidade/metabolismo , Gordura Intra-Abdominal/metabolismo , Triglicerídeos/metabolismo , Ácidos Graxos Insaturados/metabolismo , RNA Mensageiro/metabolismo , Tecido Adiposo/metabolismo
7.
Apoptosis ; 18(6): 739-50, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23456623

RESUMO

TNF-related apoptosis-inducing ligand (TRAIL) is a pro-apoptotic ligand from the TNF-alpha family that is under consideration, along with agonistic anti-TRAIL receptor antibodies, as a potential anti-tumor agent. However, most primary human tumors are resistant to monotherapy with TRAIL apoptogens, and thus the potential applicability of TRAIL in anti-tumor therapy ultimately depends on its rational combination with drugs targeting these resistances. In our high-throughput screening for novel agents/drugs that could sensitize TRAIL-resistant colorectal cancer cells to TRAIL-induced apoptosis, we found homoharringtonine (HHT), a cephalotaxus alkaloid and tested anti-leukemia drug, to be a very effective, low nanomolar enhancer of TRAIL-mediated apoptosis/growth suppression of these resistant cells. Co-treatment of TRAIL-resistant RKO or HT-29 cells with HHT and TRAIL led to the effective induction of apoptosis and the complete elimination of the treated cells. HHT suppressed the expression of the anti-apoptotic proteins Mcl-1 and cFLIP and enhanced the TRAIL-triggered activation of JNK and p38 kinases. The shRNA-mediated down-regulation of cFLIP or Mcl-1 in HT-29 or RKO cells variably enhanced their TRAIL-induced apoptosis but it did not markedly sensitize them to TRAIL-mediated growth suppression. However, with the notable exception of RKO/sh cFLIP cells, the downregulation of cFLIP or Mcl-1 significantly lowered the effective concentration of HHT in HHT + TRAIL co-treatment. Combined HHT + TRAIL therapy also led to the strong suppression of HT-29 tumors implanted into immunodeficient mice. Thus, HHT represents a very efficient enhancer of TRAIL-induced apoptosis with potential application in TRAIL-based, anti-cancer combination therapy.


Assuntos
Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Harringtoninas/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Células HT29 , Mepesuccinato de Omacetaxina , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Transplante Heterólogo
8.
Apoptosis ; 18(3): 324-36, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23179179

RESUMO

Recently, tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/Apo2L) has been shown to be a potential candidate for cancer therapy. TRAIL induces apoptosis in various cancer cells but not in normal tissues. Here we show that HCT116 and SW480 cells with a deficient mitochondrial apoptotic pathway were resistant to TRAIL-induced apoptosis, whereas HCT116 and SW480 cells with a functional mitochondrial apoptotic pathway underwent apoptosis upon exposure to TRAIL. Surprisingly, TRAIL induced phenotypic changes in cells with a dysfunctional mitochondrial apoptotic pathway, including membrane blebbing and a transient loss of adhesion properties to the substratum. Accordingly, TRAIL stimulated the ability of these cells to migrate. This behavior was the consequence of a transient TRAIL-induced ROCK1 cleavage. In addition, we report that Bax-deficient HCT116 cells exposed to TRAIL for a prolonged period lost their sensitivity to TRAIL as a result of downregulation of TRAIL receptor expression, and became resistant to combination of TRAIL and other drugs such as MG-132 and bortezomib. These findings may have important consequences for TRAIL anti-cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF/fisiologia , Caspase 3/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Mitocôndrias/metabolismo , Quinases Associadas a rho/metabolismo
9.
Talanta ; 247: 123582, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35636371

RESUMO

Sensitive electrophoretic determination of 3-hydroxybutyrate (3HB) as an indicator of human ketogenesis is performed in fused silica capillary covalently coated by an anionic copolymer of poly(acrylamide-co-sodium-2-acrylamido-2-methylpropanesulphonate) (PAMAMPS). Baseline separation of 3HB from other components of human serum is achieved in a 20 µm capillary with an effective length of 17 cm covered by 4% PAMAMPS, which generates a cathodic EOF with a mobility of 8.30 ± 0.00 · 10-9 m2/V.s in 80 mM MES/His as background electrolyte. 3HB migrates in counter-current electrophoretic mode against EOF, that effectively improving electrophoretic resolution. Sample pre-treatment is based on adding of 45 µL acetonitrile to 15 µL serum and, after shaking, a 28 mm long zone of supernatant is injected into the capillary, and sharpened after turning on a separation voltage of 20 kV using the technique of large volume sample stacking, where the EOF forces the residual acetonitrile from the capillary. When combined with universal contactless conductivity detection, the achieved LOD and LOQ are 0.43 µM and 1.44 µM, respectively, that are sufficiently low for monitoring the physiological 3HB level. The performed clinical study subsequently showed that serum 3HB increases from a concentration of 71 µM, corresponding to normal food, to level of 1924 µM after 60 h of fasting and returns to the normal physiological concentration 48 h after commencing consumption of high-saccharide food.


Assuntos
Eletroforese Capilar , Jejum , Ácido 3-Hidroxibutírico , Acetonitrilas , Resinas Acrílicas , Alcanossulfonatos , Eletroforese Capilar/métodos , Humanos
10.
Mol Cancer ; 10: 118, 2011 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-21943101

RESUMO

BACKGROUND: Colorectal cancer is a common disease that involves genetic alterations, such as inactivation of tumour suppressor genes and activation of oncogenes. Among them are RAS and BRAF mutations, which rarely coexist in the same tumour. Individual members of the Rho (Ras homology) GTPases contribute with distinct roles in tumour cell morphology, invasion and metastasis. The aim of this study is to dissect cell migration and invasion pathways that are utilised by BRAFV600E as compared to KRASG12V and HRASG12V oncoproteins. In particular, the role of RhoA (Ras homolog gene family, member A), Rac1 (Ras-related C3 botulinum toxin substrate 1) and Cdc42 (cell division cycle 42) in cancer progression induced by each of the three oncogenes is described. METHODS: Colon adenocarcinoma cells with endogenous as well as ectopically expressed or silenced oncogenic mutations of BRAFV600E, KRASG12V and HRASG12V were employed. Signalling pathways and Rho GTPases were inhibited with specific kinase inhibitors and siRNAs. Cell motility and invasion properties were correlated with cytoskeletal properties and Rho GTPase activities. RESULTS: Evidence presented here indicate that BRAFV600E significantly induces cell migration and invasion properties in vitro in colon cancer cells, at least in part through activation of RhoA GTPase. The relationship established between BRAFV600E and RhoA activation is mediated by the MEK-ERK pathway. In parallel, KRASG12V enhances the ability of colon adenocarcinoma cells Caco-2 to migrate and invade through filopodia formation and PI3K-dependent Cdc42 activation. Ultimately increased cell migration and invasion, mediated by Rac1, along with the mesenchymal morphology obtained through the Epithelial-Mesenchymal Transition (EMT) were the main characteristics rendered by HRASG12V in Caco-2 cells. Moreover, BRAF and KRAS oncogenes are shown to cooperate with the TGFß-1 pathway to provide cells with additional transforming properties. CONCLUSION: This study discriminates oncogene-specific cell migration and invasion pathways mediated by Rho GTPases in colon cancer cells and reveals potential new oncogene-specific characteristics for targeted therapeutics.


Assuntos
Movimento Celular , Proteína Oncogênica p21(ras)/genética , Proteínas Proto-Oncogênicas B-raf/genética , Transdução de Sinais/efeitos dos fármacos , Proteínas rho de Ligação ao GTP/metabolismo , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Forma Celular , Neoplasias do Colo , Regulação para Baixo , Ativação Enzimática , Transição Epitelial-Mesenquimal , Técnicas de Silenciamento de Genes , Humanos , Mutação de Sentido Incorreto , Invasividade Neoplásica , Proteína Oncogênica p21(ras)/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Pseudópodes/metabolismo , Transcrição Gênica , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta1/fisiologia , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP
11.
Nutrients ; 14(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35011022

RESUMO

The aim of this study was to investigate the possible beneficial effects of exercise training (ET) with omega-3/Calanus oil supplementation on cardiorespiratory and adiposity parameters in elderly women. Fifty-five women (BMI: 19-37 kg/m2, 62-80 years old) were recruited and randomly assigned to the 4 month intervention with ET and omega-3 supplementation (Calanus oil, ET-Calanus) or ET and the placebo (sunflower oil; ET-Placebo). The body composition was determined by dual-energy X-ray absorptiometry (DXA), and cardiorespiratory parameters were measured using spiroergometry and PhysioFlow hemodynamic testing. Both interventions resulted in an increased lean mass whereas the fat mass was reduced in the leg and trunk as well as the android and gynoid regions. The content of trunk fat (in percent of the total fat) was lower and the content of the leg fat was higher in the ET-Calanus group compared with the ET-Placebo. Although both interventions resulted in similar improvements in cardiorespiratory fitness (VO2max), it was explained by an increased peripheral oxygen extraction (a-vO2diff) alone in the ET-Placebo group whereas increased values of both a-vO2diff and maximal cardiac output (COmax) were observed in the ET-Calanus group. Changes in COmax were associated with changes in systemic vascular resistance, circulating free fatty acids, and the omega-3 index. In conclusion, Calanus oil supplementation during a 4 month ET intervention in elderly women improved the cardiorespiratory function, which was due to combined central and peripheral cardiodynamic mechanisms.


Assuntos
Envelhecimento/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Suplementos Nutricionais , Exercício Físico/fisiologia , Ácidos Graxos Ômega-3/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Composição Corporal , Débito Cardíaco , Feminino , Humanos , Pessoa de Meia-Idade , Plâncton/química , Resistência Vascular
12.
Sci Rep ; 11(1): 8171, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33854130

RESUMO

Later stages of secondary lymphedema are associated with the massive deposition of adipose tissue (AT). The factors driving lymphedema-associated AT (LAT) expansion in humans remain rather elusive. We hypothesized that LAT expansion could be based on alterations of metabolic, adipogenic, immune and/or angiogenic qualities of AT. AT samples were acquired from upper limbs of 11 women with unilateral breast cancer-related lymphedema and 11 healthy women without lymphedema. Additional control group of 11 female breast cancer survivors without lymphedema was used to assess systemic effects of lymphedema. AT was analysed for adipocyte size, lipolysis, angiogenesis, secretion of cytokines, immune and stem cell content and mRNA gene expression. Further, adipose precursors were isolated and tested for their proliferative and adipogenic capacity. The effect of undrained LAT- derived fluid on adipogenesis was also examined. Lymphedema did not have apparent systemic effect on metabolism and cytokine levels, but it was linked with higher lymphocyte numbers and altered levels of several miRNAs in blood. LAT showed higher basal lipolysis, (lymph)angiogenic capacity and secretion of inflammatory cytokines when compared to healthy AT. LAT contained more activated CD4+ T lymphocytes than healthy AT. mRNA levels of (lymph)angiogenic markers were deregulated in LAT and correlated with markers of lipolysis. In vitro, adipose cells derived from LAT did not differ in their proliferative, adipogenic, lipogenic and lipolytic potential from cells derived from healthy AT. Nevertheless, exposition of preadipocytes to LAT-derived fluid improved their adipogenic conversion when compared with the effect of serum. This study presents results of first complex analysis of LAT from upper limb of breast cancer survivors. Identified LAT alterations indicate a possible link between (lymph)angiogenesis and lipolysis. In addition, our in vitro results imply that AT expansion in lymphedema could be driven partially by exposition of adipose precursors to undrained LAT-derived fluid.


Assuntos
Tecido Adiposo/metabolismo , Linfedema Relacionado a Câncer de Mama/genética , Citocinas/genética , Perfilação da Expressão Gênica/métodos , Linfedema/genética , Adulto , Idoso , Linfedema Relacionado a Câncer de Mama/metabolismo , Sobreviventes de Câncer , Estudos de Casos e Controles , Feminino , Regulação da Expressão Gênica , Humanos , Lipólise , Linfedema/metabolismo , Pessoa de Meia-Idade
13.
J Healthc Eng ; 2021: 9986874, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603652

RESUMO

Radiofrequency ablation (RFA) is a routinely used, safe, and effective method for the tissue destruction. Often, in case of its application in malignant conditions, the extent of tissue destruction is insufficient due to the size of the target lesion, as well as due to the risk of heat-induced damage to the surrounding organs. Nevertheless, there are conditions requiring superficial precise-depth ablation with preservation of deeper layers. These are represented, for example, by mucosal resurfacing in case of Barrett's esophagus or treatment of recurrent mucosal bleeding in case of chronic radiation proctitis. Recently, new indications for intraluminal RFA use emerged, especially in the pancreatobiliary tract. In the case of intraductal use of RFA (e.g., biliary and pancreatic tract), there are currently available rigid and needle tip catheters. An expandable balloon-based RFA catheter suitable for use in such small-diameter tubular organs could be of benefit due to possible increase of contact between the probe and the target tissue; however, to prevent excessive tissue damage, a compatible generator suitable for low-impedance catheter/tissue is essential. This project aimed to develop a radiofrequency ablation generator and bipolar balloon-based catheter optimized for the application in the conditions of low-impedance tissue and (micro)endoluminal environment. Subsequent evaluation of biological effect in vivo was performed using duodenal mucosa in Wistar rat representing conditions of endoluminal radiofrequency ablation of low-impedance tissue. Experiments confirming the safety and feasibility of RFA with our prototype devices were conducted.


Assuntos
Ablação por Radiofrequência , Animais , Catéteres , Duodeno/cirurgia , Impedância Elétrica , Ratos , Ratos Wistar , Resultado do Tratamento
14.
Metab Syndr Relat Disord ; 18(3): 146-153, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31928504

RESUMO

Background: Exposure to intermittent hypoxia (IH) may play a role in the development of metabolic impairments in the context of obstructive sleep apnea syndrome, probably by elevated plasma levels of free fatty acids. Employing gas-permeable cultureware to grow differentiated human and mouse adipocytes in vitro, we directly studied the effects of pericellular oxygen fluctuations on key adipocyte metabolic functions-spontaneous lipolytic rates, triglyceride accumulation, de novo lipogenesis, and expression of adipocyte-specific marker genes. Materials and Methods: 3T3-L1 fibroblasts and human subcutaneous preadipocytes were differentiated under conditions that induced repetitive pericellular-oxygen cycles IH between 1% O2 (5 min) and 16% O2 (5 min), continuously for 14 days or under control conditions. Chemicals were used to inhibit the flux of acetyl-CoA from glycolysis (alfa-cyano-4-hydroxy cinnamate) or the tricarboxylic acid cycle (SB204990), or to stimulate the flux of acetyl-CoA from pyruvate to the lipogenic pool. Lipolytic rate, intracellular lipids, and expression of adipocyte differentiation markers were assessed and t-test or ANOVA were used to find significant differences. Results: The rate of lipolysis increased by 211% in 3T3-L1 cells and by 39% in obese human adipocytes. Exposure to IH reduced intracellular lipid stores by 37% and reduced the expression of adipocyte differentiation markers. Pharmacological stimulation or inhibition of de novo lipogenesis did not modify the intracellular lipid content under IH. Conclusions: Pericellular oxygen fluctuations directly stimulated lipolysis, but did not increase de novo lipogenesis from endogenous substrates. Similarly, IH hampered adipocyte differentiation from precursors.


Assuntos
Diferenciação Celular/fisiologia , Hipóxia Celular/fisiologia , Lipogênese/fisiologia , Lipólise/fisiologia , Células 3T3-L1 , Acetilcoenzima A/metabolismo , Adipócitos/metabolismo , Animais , Diferenciação Celular/genética , Hipóxia Celular/genética , Ciclo do Ácido Cítrico , Perfilação da Expressão Gênica , Glicólise , Humanos , Cinética , Lipogênese/genética , Lipólise/genética , Camundongos , Consumo de Oxigênio/genética , Triglicerídeos/metabolismo
15.
Front Endocrinol (Lausanne) ; 11: 582732, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33658980

RESUMO

Aim: Development of type 2 diabetes (T2DM) is associated with disturbances in immune and metabolic status that may be reflected by an altered gene expression profile of peripheral blood mononuclear cells (PBMC). To reveal a potential family predisposition to these alterations, we investigated the regulation of gene expression profiles in circulating CD14+ and CD14- PBMC in fasting conditions and in response to oral glucose tolerance test (OGTT) in glucose tolerant first-degree relatives (FDR) of T2DM patients and in control subjects. Materials and Methods: This work is based on the clinical study LIMEX (NCT03155412). Non-obese 12 non-diabetic (FDR), and 12 control men without family history of diabetes matched for age and BMI underwent OGTT. Blood samples taken before and at the end of OGTT were used for isolation of circulating CD14+ and CD14- PBMC. In these cells, mRNA levels of 94 genes related to lipid and carbohydrate metabolism, immunity, and inflammation were assessed by qPCR. Results: Irrespectively of the group, the majority of analyzed genes had different mRNA expression in CD14+ PBMC compared to CD14- PBMC in the basal (fasting) condition. Seven genes (IRS1, TLR2, TNFα in CD14+ PBMC; ABCA1, ACOX1, ATGL, IL6 in CD14- PBMC) had different expression in control vs. FDR groups. OGTT regulated mRNA levels of nine genes selectively in CD14+ PBMC and of two genes (ABCA1, PFKL) selectively in CD14-PBMC. Differences in OGTT-induced response between FDR and controls were observed for EGR2, CCL2 in CD14+ PBMC and for ABCA1, ACOX1, DGAT2, MLCYD, and PTGS2 in CD14- PBMC. Conclusion: This study revealed a different impact of glucose challenge on gene expression in CD14+ when compared with CD14- PBMC fractions and suggested possible impact of family predisposition to T2DM on basal and OGTT-induced gene expression in these PBMC fractions. Future studies on these putative alterations of inflammation and lipid metabolism in fractionated PBMC in larger groups of subjects are warranted.


Assuntos
Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/patologia , Regulação da Expressão Gênica , Predisposição Genética para Doença , Leucócitos Mononucleares/patologia , Receptores de Lipopolissacarídeos/metabolismo , Transcriptoma , Adulto , Glicemia/análise , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Teste de Tolerância a Glucose , Humanos , Leucócitos Mononucleares/metabolismo , Masculino
16.
J Clin Endocrinol Metab ; 105(12)2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32902644

RESUMO

CONTEXT: Metabolic disturbances and a pro-inflammatory state associated with aging and obesity may be mitigated by physical activity or nutrition interventions. OBJECTIVE: The aim of this study is to assess whether physical fitness/exercise training (ET) alleviates inflammation in adipose tissue (AT), particularly in combination with omega-3 supplementation, and whether changes in AT induced by ET can contribute to an improvement of insulin sensitivity and metabolic health in the elderly. DESIGN, PARTICIPANTS, MAIN OUTCOME MEASURES: The effect of physical fitness was determined in cross-sectional comparison of physically active/physically fit (trained) and sedentary/less physically fit (untrained) older women (71 ± 4 years, n = 48); and in double-blind randomized intervention by 4 months of ET with or without omega-3 (Calanus oil) supplementation (n = 55). Physical fitness was evaluated by spiroergometry (maximum graded exercise test) and senior fitness tests. Insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp. Samples of subcutaneous AT were used to analyze mRNA gene expression, cytokine secretion, and immune cell populations. RESULTS: Trained women had lower mRNA levels of inflammation and oxidative stress markers, lower relative content of CD36+ macrophages, and higher relative content of γδT-cells in AT when compared with untrained women. Similar effects were recapitulated in response to a 4-month ET intervention. Content of CD36+ cells, γδT-cells, and mRNA expression of several inflammatory and oxidative stress markers correlated to insulin sensitivity and cardiorespiratory fitness. CONCLUSIONS: In older women, physical fitness is associated with less inflammation in AT. This may contribute to beneficial metabolic outcomes achieved by ET. When combined with ET, omega-3 supplementation had no additional beneficial effects on AT inflammatory characteristics.


Assuntos
Tecido Adiposo/patologia , Envelhecimento/fisiologia , Exercício Físico/fisiologia , Inflamação/prevenção & controle , Tecido Adiposo/imunologia , Tecido Adiposo/metabolismo , Idoso , Idoso de 80 Anos ou mais , Aptidão Cardiorrespiratória/fisiologia , Estudos Transversais , Terapia por Exercício , Feminino , Humanos , Inflamação/metabolismo , Inflamação/patologia , Resistência à Insulina/fisiologia , Pessoa de Meia-Idade , Força Muscular/fisiologia , Aptidão Física/fisiologia
17.
J Physiol Biochem ; 75(3): 253-262, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30912009

RESUMO

In aging, the capacity of subcutaneous adipose tissue (SAT) to store lipids decreases and this results in metabolically unfavorable fat redistribution. Triggers of this age-related SAT dysfunction may include cellular senescence or endoplasmic reticulum (ER) stress. Therefore, we compared lipogenic capacity of SAT between young and older women and investigated its relation to senescence and ER stress markers. Samples of SAT and corresponding SAT-derived primary preadipocytes were obtained from two groups of women differing in age (36 vs. 72 years, n = 15 each) but matched for fat mass. mRNA levels of selected genes (lipogenesis: ACACA, FASN, SCD1, DGAT2, ELOVL6; senescence: p16, p21, NOX4, GDF15; ER stress-ATF4, XBP1s, PERK, HSPA5, GADD34, HYOU1, CHOP, EDEM1, DNAJC3) were assessed by qPCR, protein levels of GDF15 by ELISA, and mitochondrial function by the Seahorse Analyzer. Compared to the young, SAT and in vitro differentiated adipocytes from older women exhibited reduced mRNA expression of lipogenic enzymes. Out of analyzed senescence and ER stress markers, the only gene, whose expression correlated negatively with the expression of lipogenic enzymes in both SAT and adipocytes, was GDF15, a marker of not only senescence but also mitochondrial dysfunction. In line with this, inhibition of mitochondrial ATP synthase in adipocytes strongly upregulated GDF15 while reduced expression of lipogenic enzymes. Moreover, adipocytes from older women had a tendency for diminished mitochondrial capacity. Thus, a reduced lipogenic capacity of adipocytes in aged SAT appears to be linked to mitochondrial dysfunction rather than to ER stress or accumulation of senescent cells.


Assuntos
Adipócitos/metabolismo , Envelhecimento/metabolismo , Fator 15 de Diferenciação de Crescimento/metabolismo , Lipogênese , Mitocôndrias/metabolismo , Gordura Subcutânea/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Diferenciação Celular , Senescência Celular , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Feminino , Humanos
18.
Artigo em Inglês | MEDLINE | ID: mdl-30386299

RESUMO

Metabolic impairments associated with obstructive sleep apnea syndrome (OSA) are linked to tissue hypoxia, however, the explanatory molecular and endocrine mechanisms remain unknown. Using gas-permeable cultureware, we studied the chronic effects of mild and severe hypoxia on free fatty acid (FFA) uptake, storage, and oxidation in L6 myotubes under 20, 4, or 1% O2. Additionally, the impact of metformin and the peroxisome proliferator-activated receptor (PPAR) ß/δ agonist, called GW501516, were investigated. Exposure to mild and severe hypoxia reduced FFA uptake by 37 and 32%, respectively, while metformin treatment increased FFA uptake by 39% under mild hypoxia. GW501516 reduced FFA uptake under all conditions. Protein expressions of CD36 (cluster of differentiation 36) and SCL27A4 (solute carrier family 27 fatty acid transporter, member 4) were reduced by 17 and 23% under severe hypoxia. Gene expression of UCP2 (uncoupling protein 2) was reduced by severe hypoxia by 81%. Metformin increased CD36 protein levels by 28% under control conditions and SCL27A4 levels by 56% under mild hypoxia. Intracellular lipids were reduced by mild hypoxia by 18%, while in controls only, metformin administration further reduced intracellular lipids (20% O2) by 36%. Finally, palmitate oxidation was reduced by severe hypoxia, while metformin treatment reduced non-mitochondrial O2 consumption, palmitate oxidation, and proton leak at all O2 levels. Hypoxia directly reduced FFA uptake and intracellular lipids uptake in myotubes, at least partially, due to the reduction in CD36 transporters. Metformin, but not GW501516, can increase FFA uptake and SCL27A4 expression under mild hypoxia. Described effects might contribute to elevated plasma FFA levels and metabolic derangements in OSA.

19.
Photochem Photobiol ; 82(2): 432-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16613522

RESUMO

In the present study we investigated the photosensitizing properties of two novel mono- and bis-cyclodextrin tetrakis (pentafluorophenyl) porphyrin derivatives in several tumor cell lines and in BALB/c mice bearing subcutaneously transplanted syngeneic mouse mammary carcinoma 4T1. Both studied sensitizers were localized mainly in lysosomes and were found to induce cell death by triggering apoptosis in human leukemic cells HL-60. In 4T1 and other cell lines both apoptotic and necrotic modes of cell death occurred depending on drug and light doses. Mono-cyclodextrin porphyrin derivative P(beta-CD)1 exhibited stronger in vitro phototoxic effect than bis-cyclodextrin derivative P(beta-CD)2. However, in vivo P(beta-CD)2 displayed faster tumor uptake with maximal accumulation 6 h after application, leading to complete and prolonged elimination of subcutaneous tumors within 3 days after irradiation (100 J cm(-2)). In contrast, P(beta-CD)1 uptake was slower (48 h) and the reduction of tumor mass was only transient, reaching the maximum at the 12 h interval when a favorable tumor-to-skin ratio appeared. Thus, P(beta-CD)2 represents a new photosensitizing drug displaying fast and selective tumor uptake, strong antitumor activity and fast elimination from the body.


Assuntos
Antineoplásicos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Pele/efeitos dos fármacos , beta-Ciclodextrinas/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Dermatite Fototóxica/tratamento farmacológico , Humanos , Lisossomos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Pele/efeitos da radiação , Fatores de Tempo , Células Tumorais Cultivadas
20.
Atherosclerosis ; 250: 151-7, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27236705

RESUMO

BACKGROUND: Obesity represents a high risk factor for the development of atherosclerosis and is associated with a low-grade inflammation and activation of immune cells. AIMS: The aim of our study was to investigate the effect of a short-term lipid infusion on immune cells in blood and subcutaneous abdominal adipose tissue (SAAT) in obese women. METHODS: Seven-hour intravenous lipid/control infusions were performed in two groups of women (n = 15, n = 10, respectively). Before and at the end of the infusion, SAAT and blood samples were obtained and relative content and phenotype of immune cells were analyzed using flow cytometry. Analysis of immune cell markers, inflammation and angiogenesis markers was performed in SAAT by RT-PCR and in plasma by immunoassays. RESULTS: Relative content of CD45+/14+ and CD45+/14+/16+ populations of monocytes was reduced in circulation by 21% (p = 0.004) and by 46% (p = 0.0002), respectively, in response to hyperlipidemia, which suggested the increased adhesion of these cells to endothelium. In line with this, the levels of sICAM and sVCAM in plasma were increased by 9.4% (p = 0.016), 11.8% (p = 0.008), respectively. In SAAT, the relative content of M2 monocyte/macrophages subpopulation CD45+/14+/206+/16+ decreased by 27% (p = 0.012) and subpopulations CD14+/CD206- and CD14/+TLR4+ cells increased (p = 0.026; p = 0.049, respectively). Intralipid infusion promoted an increase of mRNA levels in SAAT: RORC (marker of proinflammatory Th17 lymphocytes) by 43% (p = 0.048), MCP-1 (78%, p = 0.028) and VEGF (68.5%, p = 0.0001). CONCLUSIONS: Acute hyperlipidemia induces a proinflammatory and proatherogenic response associated with altered relative content of immune cells in blood and SAAT in obese women.


Assuntos
Tecido Adiposo/patologia , Aterosclerose/sangue , Hiperlipidemias/sangue , Obesidade/sangue , Gordura Subcutânea Abdominal/patologia , Doença Aguda , Tecido Adiposo/metabolismo , Adulto , Aterosclerose/complicações , Biomarcadores/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Hiperlipidemias/complicações , Inflamação , Linfócitos/citologia , Macrófagos/citologia , Pessoa de Meia-Idade , Monócitos/citologia , Obesidade/complicações , Fenótipo , RNA Mensageiro/metabolismo , Gordura Subcutânea Abdominal/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA