RESUMO
The goal of this study was to evaluate the intensity of autophagy and ubiquitin-dependent proteolysis processes occurring in myocardium of left ventricle (LV) in subsequent stages of pulmonary arterial hypertension (PAH) to determine mechanisms responsible for LV mass loss in a monocrotaline-induced PAH rat model. LV myocardium samples collected from 32 Wistar rats were analyzed in an early PAH group (n = 8), controls time-paired (n = 8), an end-stage PAH group (n = 8), and their controls (n = 8). Samples were subjected to histological analyses with immunofluorescence staining, autophagy assessment by western blotting, and evaluation of ubiquitin-dependent proteolysis in the LV by immunoprecipitation of ubiquitinated proteins. Echocardiographic, hemodynamic, and heart morphometric parameters were assessed regularly throughout the experiment. Considerable morphological and hemodynamic remodeling of the LV was observed over the course of PAH. The end-stage PAH was associated with significantly impaired LV systolic function and a decrease in LV mass. The LC3B-II expression in the LV was significantly higher in the end-stage PAH group compared to the early PAH group (p = 0.040). The measured LC3B-II/LC3B-I ratios in the end-stage PAH group were significantly elevated compared to the controls (p = 0.039). Immunofluorescence staining showed a significant increase in the abundance of LC3 puncta in the end-stage PAH group compared to the matched controls. There were no statistically significant differences in the levels of expression of all ubiquitinated proteins when comparing both PAH groups and matched controls. Autophagy may be considered as the mechanism behind the LV mass loss at the end stage of PAH.
Assuntos
Autofagia , Ventrículos do Coração , Proteólise , Hipertensão Arterial Pulmonar , Ratos Wistar , Ubiquitina , Animais , Ubiquitina/metabolismo , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Ratos , Masculino , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/patologia , Modelos Animais de Doenças , Miocárdio/metabolismo , Miocárdio/patologia , Ecocardiografia , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Remodelação VentricularRESUMO
There is growing interest in the non-invasive identification and monitoring of the outcome of liver damage in obese patients. Plasma cytokeratin-18 (CK-18) fragment levels correlate with the magnitude of hepatocyte apoptosis and have recently been proposed to independently predict the presence of non-alcoholic steatohepatitis (NASH). The aim of the study was to analyze the associations of CK-18 with obesity and related complications: insulin resistance, impaired lipid metabolism and the secretion of hepatokines, adipokines and pro-inflammatory cytokines. The study involved 151 overweight and obese patients (BMI 25-40), without diabetes, dyslipidemia or apparent liver disease. Liver function was assessed based on alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT) and the fatty liver index (FLI). CK-18 M30 plasma levels, FGF-21, FGF-19 and cytokines were determined by ELISA. CK-18 values >150 U/l were accompanied by high ALT, GGT and FLI, insulin resistance, postprandial hypertriglyceridemia, elevated FGF-21 and MCP-1 and decreased adiponectin. ALT activity was the strongest independent factor influencing high CK-18 plasma levels, even after an adjustment for age, sex and BMI [ß coefficient (95%CI): 0.40 (0.19-0.61)]. In conclusion, the applied CK-18 cut-off point at 150 U/l allows to distinguish between two metabolic phenotypes in obesity.
Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Humanos , Queratina-18 , Biomarcadores/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Fenótipo , gama-Glutamiltransferase , Citocinas/metabolismo , Fígado/metabolismoRESUMO
Personalized nutrition (PN) has gained much attention as a tool for empowerment of consumers to promote changes in dietary behavior, optimizing health status and preventing diet related diseases. Generalized implementation of PN faces different obstacles, one of the most relevant being metabolic characterization of the individual. Although omics technologies allow for assessment the dynamics of metabolism with unprecedented detail, its translatability as affordable and simple PN protocols is still difficult due to the complexity of metabolic regulation and to different technical and economical constrains. In this work, we propose a conceptual framework that considers the dysregulation of a few overarching processes, namely Carbohydrate metabolism, lipid metabolism, inflammation, oxidative stress and microbiota-derived metabolites, as the basis of the onset of several non-communicable diseases. These processes can be assessed and characterized by specific sets of proteomic, metabolomic and genetic markers that minimize operational constrains and maximize the information obtained at the individual level. Current machine learning and data analysis methodologies allow the development of algorithms to integrate omics and genetic markers. Reduction of dimensionality of variables facilitates the implementation of omics and genetic information in digital tools. This framework is exemplified by presenting the EU-Funded project PREVENTOMICS as a use case.
RESUMO
Elevated glucose-dependent insulinotropic peptide (GIP) levels in obesity may predict the metabolic benefits of n-3 PUFA supplementation. This placebo-controlled trial aimed to analyze fasting and postprandial GIP response to 3-month n-3 PUFA supplementation (1.8 g/d; DHA:EPA, 5:1) along with caloric restriction (1200-1500 kcal/d) in obese subjects. Compliance was confirmed by the incorporation of DHA and EPA into red blood cells (RBCs). Blood analyses of glucose, insulin, non-esterified fatty acids (NEFAs), GIP and triglycerides were performed at fasting, and during an oral glucose tolerance test and a high fat mixed-meal tolerance test. Fatty acid composition of RBC was assessed by gas chromatography and total plasma fatty acid content and composition was measured by gas-liquid chromatography. The DHA and EPA content in RBCs significantly increased due to n-3 PUFA supplementation vs. placebo (77% vs. -3%, respectively). N-3 PUFA supplementation improved glucose tolerance and decreased circulating NEFA levels (0.750 vs. 0.615 mmol/L), as well as decreasing plasma saturated (1390 vs. 1001 µg/mL) and monounsaturated (1135 vs. 790 µg/mL) fatty acids in patients with relatively high GIP levels. The effects of n-3 PUFAs were associated with the normalization of fasting (47 vs. 36 pg/mL) and postprandial GIP levels. Obese patients with elevated endogenous GIP could be a target group for n-3 PUFA supplementation in order to achieve effects that obese patients without GIP disturbances can achieve with only caloric restriction.
RESUMO
Weight loss contributes to an increased risk of hip fracture, especially in postmenopausal women. Omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation could diminish the adverse effect of weight loss on bone health. The aim of this randomized, placebo-controlled, double-blind parallel trial was to investigate the effect of caloric restriction and n-3 PUFA supplement intake on osteogenic markers (carboxylated osteocalcin (Gla-OC); procollagen I N-terminal propeptide (PINP)), as well as a bone resorption marker (C-terminal telopeptide of type I collagen (CTX-I)) in a serum of 64 middle aged individuals (BMI 25-40 kg/m2) with abdominal obesity. Bone remodeling, metabolic and inflammatory parameters and adipokines were determined before and after 3 months of an isocaloric diet (2300-2400 kcal/day) or a low-calorie diet (1200 kcal/day for women and 1500 kcal/day for men) along with n-3 PUFA (1.8 g/day) or placebo capsules. CTX-I and adiponectin concentrations were increased following 7% weight loss independently of supplement use. Changes in CTX-I were positively associated with changes in adiponectin level (rho = 0.25, p = 0.043). Thus, an increase in serum adiponectin caused by body weight loss could adversely affect bone health. N-3 PUFAs were without effect.
Assuntos
Biomarcadores/sangue , Remodelação Óssea/fisiologia , Reabsorção Óssea/etiologia , Restrição Calórica/efeitos adversos , Ácidos Graxos Ômega-3/administração & dosagem , Obesidade Abdominal/terapia , Adiponectina/sangue , Adulto , Idoso , Remodelação Óssea/efeitos dos fármacos , Reabsorção Óssea/prevenção & controle , Colágeno Tipo I/sangue , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/sangue , Osteocalcina/sangue , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Placebos , Pró-Colágeno/sangue , Redução de PesoRESUMO
The aim of this study was to identify the health risk factors associated with flavonoid intake in cohort studies investigating the association between dietary polyphenols and the risk of cardiovascular disease (CVD). A systematic search of the PubMed and EMBASE databases was performed. Prospective studies with the background characteristics given for categories of flavonoid intake were eligible to inclusion. A bivariate meta-analysis summarising the intercepts and slopes of the linear regression and a dose-response meta-analysis of differences in means were used to analyse the relationships. The intake of total flavonoids was inversely associated with BMI, alcohol consumption, saturated fat intake, and current smoking, and positively associated with vitamin E, folate, fibre, beta-carotene intake, multivitamin supplement use, and high physical activity. The results of this study underline the importance of considering the association between dietary flavonoid consumption and CVD risk in the context of a healthy lifestyle.
Assuntos
Doenças Cardiovasculares , Dieta , Flavonoides , Polifenóis , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Flavonoides/administração & dosagem , Humanos , Polifenóis/administração & dosagem , Estudos Prospectivos , Fatores de RiscoRESUMO
We hypothesised that epigenetics may play an important role in mediating fibroblast growth factor 21 (FGF21) resistance in obesity. We aimed to evaluate DNA methylation changes and miRNA pattern in obese subjects associated with high serum FGF21 levels. The study included 136 participants with BMI 27-45 kg/m2. Fasting FGF21, glucose, insulin, GIP, lipids, adipokines, miokines and cytokines were measured and compared in high serum FGF21 (n = 68) group to low FGF21 (n = 68) group. Human DNA Methylation Microarrays were analysed in leukocytes from each group (n = 16). Expression of miRNAs was evaluated using quantitative PCR-TLDA. The study identified differentially methylated genes in pathways related to glucose transport, insulin secretion and signalling, lipid transport and cellular metabolism, response to nutrient levels, thermogenesis, browning of adipose tissue and bone mineralisation. Additionally, it detected transcription factor genes regulating FGF21 and fibroblast growth factor receptor and vascular endothelial growth factor receptor pathways regulation. Increased expression of hsa-miR-875-5p and decreased expression of hsa-miR-133a-3p, hsa-miR-185-5p and hsa-miR-200c-3p were found in the group with high serum FGF21. These changes were associated with high FGF21, VEGF and low adiponectin serum levels. Our results point to a significant role of the epigenetic regulation of genes involved in metabolic pathways related to FGF21 action.
Assuntos
Epigênese Genética/genética , Fatores de Crescimento de Fibroblastos/sangue , Obesidade/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Adipocinas/sangue , Glicemia/genética , Citocinas/sangue , Metilação de DNA/genética , Fibroblastos/metabolismo , Regulação da Expressão Gênica/genética , Glucose/genética , Humanos , Lipídeos/sangue , MicroRNAs/sangue , Obesidade/genética , Obesidade/patologiaRESUMO
BACKGROUND: Epigenetics can contribute to lipid disorders in obesity. The DNA methylation pattern can be the cause or consequence of high blood lipids. The aim of the study was to investigate the DNA methylation profile in peripheral leukocytes associated with elevated LDL-cholesterol level in overweight and obese individuals. METHODS: To identify the differentially methylated genes, genome-wide DNA methylation microarray analysis was performed in leukocytes of obese individuals with high LDL-cholesterol (LDL-CH, ≥ 3.4 mmol/L) versus control obese individuals with LDL-CH, < 3.4 mmol/L. Biochemical tests such as serum glucose, total cholesterol, HDL cholesterol, triglycerides, insulin, leptin, adiponectin, FGF19, FGF21, GIP and total plasma fatty acids content have been determined. Oral glucose and lipid tolerance tests were also performed. Human DNA Methylation Microarray (from Agilent Technologies) containing 27,627 probes for CpG islands was used for screening of DNA methylation status in 10 selected samples. Unpaired t-test and Mann-Whitney U-test were used for biochemical and anthropometric parameters statistics. For microarrays analysis, fold of change was calculated comparing hypercholesterolemic vs control group. The q-value threshold was calculated using moderated Student's t-test followed by Benjamini-Hochberg multiple test correction FDR. RESULTS: In this preliminary study we identified 190 lipid related CpG loci differentially methylated in hypercholesterolemic versus control individuals. Analysis of DNA methylation profiles revealed several loci engaged in plasma lipoprotein formation and metabolism, cholesterol efflux and reverse transport, triglycerides degradation and fatty acids transport and ß-oxidation. Hypermethylation of CpG loci located in promoters of genes regulating cholesterol metabolism: PCSK9, LRP1, ABCG1, ANGPTL4, SREBF1 and NR1H2 in hypercholesterolemic patients has been found. Novel epigenetically regulated CpG sites include ABCG4, ANGPTL4, AP2A2, AP2M1, AP2S1, CLTC, FGF19, FGF1R, HDLBP, LIPA, LMF1, LRP5, LSR, NR1H2 and ZDHHC8 genes. CONCLUSIONS: Our results indicate that obese individuals with hypercholesterolemia present specific DNA methylation profile in genes related to lipids transport and metabolism. Detailed knowledge of epigenetic regulation of genes, important for lipid disorders in obesity, underlies the possibility to influence target genes by changing diet and lifestyle, as DNA methylation is reversible and depends on environmental factors. These findings give rise for further studies on factors that targets methylation of revealed genes.
Assuntos
Metilação de DNA , Epigênese Genética , Epigenômica , Hipercolesterolemia/etiologia , Metabolismo dos Lipídeos/genética , Obesidade/etiologia , Adulto , Idoso , Biomarcadores , Pesos e Medidas Corporais , Ilhas de CpG , Suscetibilidade a Doenças , Epigenômica/métodos , Feminino , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/metabolismo , Lipídeos/sangue , Masculino , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/metabolismoRESUMO
We hypothesized that some molecular pathways might interact to initiate the process of nervous tissue destruction, promoting cardiac autonomic neuropathy (CAN) in the course of diabetes type 1 (T1D). The study group consisted of 60 T1D patients (58.33% women/41.67% men), on standard therapy. The control group consisted of twenty healthy volunteers recruited in accordance with age, gender and body weight. The presence of CAN was documented by the Ewing test method (ProSciCard apparatus). A microarray data analysis was performed using Gene Spring version 13. The microarray results for selected genes were confirmed by real-time PCR (qRT-PCR), using specific TaqMan Gene Expression Assays. Plasma IL-6 content was measured by an enzyme-linked immunosorbent assay (ELISA). The p < 0.05 value was considered as statistically significant. The microarray analysis, confirmed by qRTPCR, showed significant up-regulation of autophagy, quantity of mitochondria, quality regulatory genes (mTOR, GABARAPL2) apoptosis, ER-stress and inflammation (NFKB1, IL1b, IL1R1, SOD1), in T1D when compared to the control group. A significantly higher IL-6 protein level was observed in T1D patients, in comparison to the control group. We concluded that the observed changes in gene expression and activation of intracellular pathways give a coherent picture of the important role of oxidative stress in inflammation and the activation of apoptosis in the pathomechanism of DM. The significance of the inflammatory process, confirmed by the increased level of the inflammation biomarker IL-6 in the pathomechanisms of CAN was shown even in patients with properly treated T1D.
Assuntos
Arritmias Cardíacas/genética , Diabetes Mellitus Tipo 1/genética , Neuropatias Diabéticas/genética , Perfilação da Expressão Gênica , Sistema de Condução Cardíaco/fisiopatologia , Adulto , Arritmias Cardíacas/etiologia , Autofagia/genética , Biomarcadores , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/terapia , Estresse do Retículo Endoplasmático/genética , Feminino , Humanos , Inflamação/genética , Interleucina-6/sangue , Interleucina-6/genética , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/genética , Reação em Cadeia da Polimerase em Tempo Real , Adulto JovemRESUMO
Nutrient excess enhances glucose-dependent insulinotropic polypeptide (GIP) secretion, which may in turn contribute to the development of liver steatosis. We hypothesized that elevated GIP levels in obesity may affect markers of liver injury through microRNAs. The study involved 128 subjects (body mass index (BMI) 25-40). Fasting and postprandial GIP, glucose, insulin, and lipids, as well as fasting alanine aminotransferase (ALT), γ-glutamyltransferase (GGT), cytokeratin-18, fibroblast growth factor (FGF)-19, and FGF-21 were determined. TaqMan low density array was used for quantitative analysis of blood microRNAs. Fasting GIP was associated with ALT [ß = 0.16 (confidence interval (CI): 0.01-0.32)], triglycerides [ß = 0.21 (95% CI: 0.06-0.36], and FGF-21 [ß = 0.20 (95%CI: 0.03-0.37)]; and postprandial GIP with GGT [ß = 0.17 (95%CI: 0.03-0.32)]. The odds ratio for elevated fatty liver index (>73%) was 2.42 (95%CI: 1.02-5.72) for high GIP versus low GIP patients. The miRNAs profile related to a high GIP plasma level included upregulated miR-136-5p, miR-320a, miR-483-5p, miR-520d-5p, miR-520b, miR-30e-3p, and miR-571. Analysis of the interactions of these microRNAs with gene expression pathways suggests their potential contribution to the regulation of the activity of genes associated with insulin resistance, fatty acids metabolism, and adipocytokines signaling. Exaggerated fasting and postprandial secretion of GIP in obesity are associated with elevated liver damage markers as well as FGF-21 plasma levels. Differentially expressed microRNAs suggest additional, epigenetic factors contributing to the gut-liver cross-talk.
Assuntos
Fígado Gorduroso/sangue , Polipeptídeo Inibidor Gástrico/sangue , MicroRNAs/sangue , Obesidade/sangue , Adipocinas/sangue , Adulto , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Epigênese Genética , Jejum/sangue , Ácidos Graxos/sangue , Fígado Gorduroso/etiologia , Fígado Gorduroso/genética , Feminino , Fatores de Crescimento de Fibroblastos/sangue , Humanos , Insulina/sangue , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/genética , Razão de Chances , Período Pós-Prandial , Transdução de Sinais/genéticaRESUMO
OBJECTIVE: To evaluate the effect of insulin resistance in obesity on the expression in whole blood of mRNA and miRNA affecting bone homeostasis as well as to estimate the influence of oral glucose load (OGTT) on serum osteocalcin concentration in obese individuals with and without insulin resistance. DESIGN: Cross-sectional study. METHODS: Carboxylated (cOC), undercarboxylated (ucOC) and total osteocalcin were measured by ELISA in the serum of obese subjects with insulin resistance (n = 41) and obese subjects without insulin resistance (n = 41) (control group) during OGTT. Analysis of gene expression (microarray) and miRNAs (real-time PCR) was performed in venous blood (representating samples) collected before OGTT from obese with insulin resistance and controls. RESULTS: Obese subjects with insulin resistance (higher HOMA-IR and lower oral glucose insulin sensitivity index) presented significantly increased expression of WNT signalling inhibitors (DKK1, DKK2, SOST, SFRP1) and downregulation of the key factor in WNT signalling - ß catenin participating in osteoblasts differentiation. Expression of miRNA involved in osteoblastogenesis was also inhibited (miR-29b, miR-181a, miR-210, miR-324-3p). During OGTT, contrary to the control group, subjects with insulin resistance presented suppression of cOC and total OC decrease after 1 and 2 h of oral glucose load. CONCLUSIONS: Obese subjects with insulin resistance may have defects in osteoblastogenesis that was demonstrated via key signalling molecules mRNA downregulation, and increased expression of WNT antagonists as well as inhibition of expression of miRNA participating in the regulation of osteoblast differentiation. Disturbed osteoblastogenesis in insulin-resistant subjects results in the suppression of blood carboxylated and total osteocalcin decrease during OGTT.
Assuntos
Remodelação Óssea/fisiologia , Resistência à Insulina/fisiologia , MicroRNAs/sangue , RNA Mensageiro/sangue , Adulto , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Obesidade/etiologia , Obesidade/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Via de Sinalização Wnt/fisiologiaRESUMO
Nutrients influence bone turnover. Carboxylated osteocalcin (Gla-OC) participates in bone formation whereas its undercarboxylated form (Glu-OC) acts as a hormone in glucose metabolism. The aim of the study was to determine the responses of Gla-OC, Glu-OC, and total-OC (calculated as the sum of Gla-OC and Glu-OC) to a high fat mixed meal tolerance test (HFMTT) in non-obese (body mass index (BMI) < 30 kg/m², n = 24) and obese subjects (30 < BMI < 40 kg/m², n = 70) (both sexes, aged 25â»65 years). Serum Gla-OC and Glu-OC were measured at baseline as well as at 2 and 6 h during a HFMTT by enzyme-linked immunosorbent assay (ELISA). Baseline Gla-OC, Glu-OC, and total-OC levels were lower in obese individuals compared to non-obese participants (p = 0.037, p = 0.016 and p = 0.005, respectively). The decrease in Gla-OC and total-OC, but not in Glu-OC, concentrations during the HFMTT was suppressed in obese, but not in non-obese controls (p < 0.05, p < 0.01, p = 0.08, respectively). Subjects with the highest homeostatic model assessment for insulin resistance (HOMA-IR) index values had a less pronounced decrease in total-OC compared to patients with values of HOMA-IR index in the 1st quartile (p < 0.05). Net incremental area under Gla-OC inversely correlated with adiponectin (rho = -0.35, p = 0.001). Increase in insulin sensitivity and adiponectin level in obese subjects could beneficially influence postprandial bone turnover expressed by osteocalcin concentration.
Assuntos
Gorduras na Dieta/efeitos adversos , Refeições , Osteocalcina/sangue , Adulto , Idoso , Estudos de Casos e Controles , Gorduras na Dieta/administração & dosagem , Humanos , Resistência à Insulina , Pessoa de Meia-Idade , ObesidadeRESUMO
Glucagon-like peptide 1 receptor agonists (GLP-1RAs) are relatively new pharmacological agents used to normalize glucose level in type 2 diabetes. Recently, GLP-1RAs have been approved for the treatment of obesity to reduce body weight in non-diabetic patients. The extra-pancre-atic effects of GLP-1RAs, as well as their molecular mechanism of action, are still poorly understood. Thus this study was aimed to verify the hypothesis that the mechanism of action of the GLP-1RAs involves mitochondria and that GLP-1RAs administration can improve mitochondrial functions. For this purpose, preadipocytes CHUBS7 were differentiated to mature adipocytes and then stimulated with GLP-1RA, exendin-4 at 100 nM for 24 h. Oxygen consumption rates, mitochondrial membrane potential, intracellular ATP (adenosine triphosphate) level, SIRT1 and SIRT3 gene expression and the histone deacetylases' activity were measured. Exendin-4 was found to uncouple mitochondrial electron transport from ATP synthesis, slightly decreasing mitochondrial membrane potential in mature adipocytes. Routine respiration and uncoupled oxy- gen consumption rates were higher in exendin-4 treated adipocytes than in the non-treated cells. The ATP level remained unchanged. Exendin-4 enhanced SIRT1 and SIRT3 genes expression. Histone deacetylases' activity in the nuclear fraction was not affected by exendin-4, although the activity of class III histone deacetylases was increased. All of the effects on mitochondrial bioenergetics induced by exendin-4 were abolished by addition of glucagon-like peptide 1 receptor antagonist. In conclusion, exendin-4 activates the sirtuin pathway and increases energy expenditure in human adipocytes. Our results suggest another mechanism that may be responsible for body weight reduction observed in patients using GLP-1RAs.
Assuntos
Adipócitos/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Peptídeos/farmacologia , Peçonhas/farmacologia , Trifosfato de Adenosina/metabolismo , Adipócitos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Exenatida , Regulação da Expressão Gênica/efeitos dos fármacos , Histona Desacetilases/metabolismo , Humanos , Incretinas/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Oxigênio/metabolismo , Sirtuína 1/genética , Sirtuína 3/genéticaRESUMO
Carboxylated osteocalcin (Gla-OC) contributes to the bone formation, whereas its undercarboxylated form (Glu-OC) takes part in the energy metabolism. In vitro studies had shown that treatment of osteoblast-like cells with advanced glycation end product-modified bovine serum resulted in reduced synthesis of collagen 1 and osteocalcin. The aim of this study was to find association between Gla-OC and markers of protein glycation, oxidation and nitration, as well as pro-inflammatory and antioxidant defense markers in obese subjects. Non-obese [(body mass index (BMI)<30 kg/m; n=34)] and obese subjects (30Assuntos
Produtos Finais de Glicação Avançada/urina
, Obesidade/metabolismo
, Osteocalcina/sangue
, Adulto
, Idoso
, Antioxidantes/metabolismo
, Biomarcadores/metabolismo
, Estudos de Casos e Controles
, Feminino
, Humanos
, Cinurenina/análogos & derivados
, Cinurenina/urina
, Lisina/análogos & derivados
, Lisina/urina
, Masculino
, Pessoa de Meia-Idade
, Obesidade/sangue
, Obesidade/urina
, Osteocalcina/metabolismo
, Estresse Oxidativo
, Proteínas/metabolismo
RESUMO
BACKGROUND: Carboxylated osteocalcin (Gla-OC) participates in bone remodeling, whereas the undercarboxylated form (Glu-OC) takes part in energy metabolism. This study was undertaken to compare the blood levels of Glu-OC and Gla-OC in nonobese, healthy obese, and prediabetic volunteers and correlate it with the metabolic markers of insulin resistance and early markers of inflammation. METHODS: Nonobese (body mass index [BMI] <30 kg/m2 ; n = 34) and obese subjects (30 Assuntos
Ácidos Carboxílicos/química
, Inflamação/etiologia
, Resistência à Insulina
, Doenças Metabólicas/etiologia
, Obesidade/complicações
, Osteocalcina/sangue
, Estado Pré-Diabético/complicações
, Adulto
, Idoso
, Biomarcadores/sangue
, Glicemia/análise
, Metabolismo Energético
, Feminino
, Seguimentos
, Humanos
, Inflamação/sangue
, Masculino
, Doenças Metabólicas/sangue
, Pessoa de Meia-Idade
, Obesidade/sangue
, Estado Pré-Diabético/sangue
, Prognóstico
RESUMO
The n-3 polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) may reduce low-grade inflammation associated with obesity. The relationship between therapeutic response to n-3 PUFAs and modification of the transcriptome in obesity or metabolic syndrome remains to be explored. Blood samples were obtained from women with obesity before and after three-months supplementation with a moderate dose of n-3 PUFAs (1.8g EPA+DHA per day) or from controls. n-3 PUFAs (GC) and plasma concentrations of lipoxins, resolvins, protectin X (GC-MS/MS) and inflammatory markers (ELISA) were measured. Whole blood transcriptome was assayed using microarray. Women supplemented with n-3 PUFAs for 3months had significantly higher levels of EPA and DHA in plasma phosphatidylcholine. n-3 PUFA supplementation, in contrast to placebo, significantly decreased the concentrations of several inflammatory markers (SELE, MCP-1, sVCAM-1, sPECAM-1, and hsCRP), fasting triglycerides and insulin and increased the concentrations of pro-resolving DHA derivatives in plasma. The microarray data demonstrated effects of n-3 PUFAs on PPAR-α, NRF2 and NF-κB target genes. N-3 PUFAs increased DHA-derived pro-resolving mediators in women with obesity. Elevated resolvins and up-regulation of the resolvin receptor occurred in parallel with activation of PPAR-α target genes related to lipid metabolism and of NRF2 up-regulated antioxidant enzymes.
Assuntos
Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Lipídeos/biossíntese , Obesidade/sangue , Obesidade/genética , Transcriptoma/genética , Adulto , Idoso , Ácidos Graxos Ômega-3/farmacologia , Feminino , Perfilação da Expressão Gênica , Humanos , Pessoa de Meia-IdadeRESUMO
The glyoxalase system in the cytoplasm of cells provides the primary defence against glycation by methylglyoxal catalysing its metabolism to D-lactate. Methylglyoxal is the precursor of the major quantitative advanced glycation endproducts in physiological systems - arginine-derived hydroimidazolones and deoxyguanosine-derived imidazopurinones. Glyoxalase 1 of the glyoxalase system was linked to anthropometric measurements of obesity in human subjects and to body weight in strains of mice. Recent conference reports described increased weight gain on high fat diet-fed mouse with lifelong deficiency of glyoxalase 1 deficiency, compared to wild-type controls, and decreased weight gain in glyoxalase 1-overexpressing transgenic mice, suggesting a functional role of glyoxalase 1 and dicarbonyl stress in obesity. Increased methylglyoxal, dicarbonyl stress, in white adipose tissue and liver may be a mediator of obesity and insulin resistance and thereby a risk factor for development of type 2 diabetes and non-alcoholic fatty liver disease. Increased methylglyoxal formation from glyceroneogenesis on adipose tissue and liver and decreased glyoxalase 1 activity in obesity likely drives dicarbonyl stress in white adipose tissue increasing the dicarbonyl proteome and related dysfunction. The clinical significance will likely emerge from on-going clinical evaluation of inducers of glyoxalase 1 expression in overweight and obese subjects. Increased transcapillary escape rate of albumin and increased total body interstitial fluid volume in obesity likely makes levels of glycation of plasma protein unreliable indicators of glycation status in obesity as there is a shift of albumin dwell time from plasma to interstitial fluid, which decreases overall glycation for a given glycemic exposure.
Assuntos
Ácido Láctico/metabolismo , Lactoilglutationa Liase/metabolismo , Obesidade/metabolismo , Aldeído Pirúvico/metabolismo , Estresse Fisiológico , Animais , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Camundongos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/complicações , Obesidade/patologiaRESUMO
BACKGROUD: Glycemic control may be associated with inflammatory status in type 1 diabetes (T1DM). We examined the association between glucose control parameters and circulating inflammation markers in T1DM. METHODS: The study included 101 T1DM patients treated with personal insulin pumps (T1DM duration 15.2 + 7.3 years). The analysed glycemic parameters included HbA1c, mean glucose level, standard deviation and number of hypoglycemic episodes (glucose <55 mg/dL) from the last 7 days. Blood was collected for testing inflammatory markers (IL-6, VCAM, ICAM, E-selectin). RESULTS: The T1DM cohort had good glycemic control (HbA1c 7.1 ± 0.8%, mean daily glucose 141.5 ± 27.1 mg/dL and the mean number of hypoglycemic episodes was 5.6 ± 4.0/week). In a forward stepwise multiple linear regression analysis the number of hypoglycemic episodes predicted the levels of the investigated markers (sICAM p = 0.0019, sVCAM p = 0.021, sE-selectin p = 0.048, and IL-6 p = 0.049). None of the other glycemic parameters was shown to be an independent predictor. CONCLUSIONS: For the first time, we report an association between the number of mild hypoglycemic episodes, recorded in a real life setting, and the level of inflammatory markers in T1DM patients with good glycemic control.
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Diabetes Mellitus Tipo 1/sangue , Hipoglicemia/sangue , Insulina/administração & dosagem , Adulto , Biomarcadores/sangue , Glicemia/análise , Estudos de Coortes , Complicações do Diabetes/sangue , Diabetes Mellitus Tipo 1/complicações , Selectina E/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemia/complicações , Hipoglicemiantes/uso terapêutico , Inflamação , Bombas de Infusão , Molécula 1 de Adesão Intercelular/sangue , Masculino , Pessoa de Meia-Idade , Molécula 1 de Adesão de Célula Vascular/sangueRESUMO
Mediators such as cytokines, eicosanoids, nitric oxide and growth factors may regulate adipogenesis as well as inflammation. It is well documented that production of some form of eicosanoids activates lipid synthesis during adipogenesis but also contributes to the formation of factors maintaining low-level systemic inflammation. Developing nutrients for reduction of adipogenesis and inflammation can enhance preventive efficacy of daily diet. This study examined the effects of free fatty acid influence on changes in lipid biosynthesis and corresponding gene expression during differentiation of human subcutaneous adipose tissue stromal vascular fraction (SVF) cells. Proadipogenic conditions promoted SVF cell differentiation and lipid droplet (LD) formation up to 15 days. This correlated with gene expression of adipocyte differentiation markers as well as inflammatory cytokines and their receptors. Addition of free fatty acids to differentiation medium increased their incorporation during the first period of differentiation (48 h). Presence of eicosanoid acid (EPA) during the initial period of differentiation by elevation of Perilipin 3 protein (TIP47), may be responsible for smaller LD formation. Presence of arachidonic acid (AA) tends to deposit lipids in large form of LDs. Prolongation of differentiation up to 15 days decreased AA or EPA in cellular lipids. PUFA through up-regulation of both phospholipase 2 and enzymes related to eicosanoid production influenced type and quantity of eicosanoids which regulated the extent of SVF cell differentiation. Formation of small LDs and reduction of pro-inflammatory mediators in adipose tissue are the consequence of eicosanoid production with anti-inflammatory potential from EPA.
Assuntos
Adipócitos/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/farmacologia , Ácido Araquidônico/farmacologia , Diferenciação Celular/efeitos dos fármacos , Ácidos Eicosanoicos/farmacologia , Células Endoteliais/efeitos dos fármacos , Adipócitos/metabolismo , Adulto , Citocinas/genética , Citocinas/metabolismo , Células Endoteliais/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metalotioneína/genética , Metalotioneína/metabolismo , Pessoa de Meia-Idade , Monoaminoxidase/genética , Monoaminoxidase/metabolismo , Perilipina-3 , Fosfolipases A2/genética , Fosfolipases A2/metabolismo , Cultura Primária de Células , Transdução de Sinais , Gordura Subcutânea/efeitos dos fármacos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismoRESUMO
BACKGROUND: Caloric restriction and n-3 polyunsaturated fatty acid (PUFA) supplementation protect from some of the metabolic complications. The aim of this study was to assess the influence of a low calorie diet with or without n-3 PUFA supplementation on glucose dependent insulinotropic polypeptide (GIP) output and insulin sensitivity markers in obese subjects. METHODS: Obese, non-diabetic subjects (BMI 30-40 kg/m(2)) and aged 25-65 yr. were put on low calorie diet (1200-1500 kcal/day) supplemented with either 1.8 g/day n-3 PUFA (DHA/EPA, 5:1) (n = 24) or placebo capsules (n = 24) for three months in a randomized placebo controlled trial. Insulin resistance markers and GIP levels were analysed from samples obtained at fasting and during an oral glucose tolerance test (OGTT). RESULTS: Caloric restriction with n-3 PUFA led to a decrease of insulin resistance index (HOMA-IR) and a significant reduction of insulin output as well as decreased GIP secretion during the OGTT. These effects were not seen with caloric restriction alone. Changes in GIP output were inversely associated with changes in red blood cell EPA content whereas fasting GIP level positively correlated with HOMA-IR index. Blood triglyceride level was lowered by caloric restriction with a greater effect when n-3 PUFA were included and correlated positively with fasting GIP level. CONCLUSIONS: Three months of caloric restriction with DHA + EPA supplementation exerts beneficial effects on insulin resistance, GIP and triglycerides. GENERAL SIGNIFICANCE: Combining caloric restriction and n-3 PUFA improves insulin sensitivity, which may be related to a decrease of GIP levels.