RESUMO
BACKGROUND: Altered serum nitric oxide (NO) levels in patients with diabetes mellitus (DM) have been reported by different studies; however, results are still controversial. Until this date, no meta-analysis evaluated the association of NO levels with DM. Thus, this paper describes a meta-analysis conducted to evaluate if there is a relationship between NO levels and type 1 DM (T1DM) or type 2 DM (T2DM). METHODS: A literature search was done to identify all studies that investigated NO levels between T1DM or T2DM patients (cases) and non-diabetic subjects (controls). Measurement of nitrate and nitrite (NOx - the stable NO products) were used to estimate NO concentrations because they closely reflect NO bioavailability. Weighted mean differences (WMD) of NOx levels between case and control samples were calculated for T1DM and T2DM groups. RESULTS: Thirty studies were eligible for inclusion in the meta-analysis (8 in T1DM samples and 22 in T2DM samples). NOx levels were increased in European T1DM patients compared with controls [random effect model (REM) WMD = 8.55, 95% CI 2.88 - 14.21]. No other ethnicity was evaluated in T1DM studies. NOx levels were also increased in both European (REM WMD = 18.76, 95% CI 1.67 - 35.85) and Asian (REM WMD = 18.41, 95% CI 8.01 - 28.81) T2DM patients, but not in Latin American patients compared with controls. CONCLUSIONS: This meta-analysis detected a significant increase in NOx levels in European T1DM patients as well as European and Asian T2DM patients. Further studies in other ethnicities are necessary to confirm these data.
Assuntos
Diabetes Mellitus , Óxido Nítrico/sangue , Adolescente , Adulto , Criança , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Humanos , Adulto JovemRESUMO
Different dietary interventions have been identified as potential modifiers of adiponectin concentrations, and they may be influenced by lipid intake. We identified studies investigating the effect of dietary lipids (type/amount) on adiponectin concentrations in a systematic review with meta-analysis. A literature search was conducted until July 2013 using databases such as Medline, Embase and Scopus (MeSH terms: 'adiponectin', 'dietary lipid', 'randomized controlled trials (RCT)'). Inclusion criteria were RCT in adults analysing adiponectin concentrations with modification of dietary lipids. Among the 4930 studies retrieved, fifty-three fulfilled the inclusion criteria and were grouped as follows: (1) total dietary lipid intake; (2) dietary/supplementary n-3 PUFA; (3) conjugated linoleic acid (CLA) supplementation; (4) other dietary lipid interventions. Diets with a low fat content in comparison to diets with a high-fat content were not associated with positive changes in adiponectin concentrations (twelve studies; pooled estimate of the difference in means: -0·04 (95% CI -0·82, 0·74) µg/ml). A modest increase in adiponectin concentrations with n-3 PUFA supplementation was observed (thirteen studies; 0·27 (95% CI 0·07, 0·47) µg/ml). Publication bias was found by using Egger's test (P= 0·01) and funnel plot asymmetry. In contrast, CLA supplementation reduced the circulating concentrations of adiponectin compared with unsaturated fat supplementation (seven studies; -0·74 (95% CI -1·38, -0·10) µg/ml). However, important sources of heterogeneity were found as revealed by the meta-regression analyses of both n-3 PUFA and CLA supplementation. Results of new RCT would be necessary to confirm these findings.
Assuntos
Adiponectina/sangue , Gorduras na Dieta/administração & dosagem , Regulação para Cima , Adiponectina/agonistas , Adulto , Dieta com Restrição de Gorduras , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/uso terapêutico , Suplementos Nutricionais/efeitos adversos , Regulação para Baixo , Ácidos Graxos Ômega-3/uso terapêutico , Humanos , Ácidos Linoleicos Conjugados/efeitos adversos , Ácidos Linoleicos Conjugados/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos TestesRESUMO
AIMS/HYPOTHESIS: Oxidative stress is involved in the pathogenesis of diabetic nephropathy. The antioxidant enzyme catalase plays a key role in redox regulation in the kidney. We investigated associations of catalase gene (CAT) polymorphisms and plasma catalase activity with diabetic nephropathy in type 1 diabetic patients. METHODS: We genotyped nine single nucleotide polymorphisms (SNPs) in the CAT region in participants from the Survival Genetic Nephropathy (SURGENE) (340 French participants, 10 year follow-up) and the Génétique de la Néphropathie Diabétique (GENEDIAB) (444 Belgian and French participants, 8 year follow-up) study cohorts. Replication was performed in a Brazilian cross-sectional cohort (n = 451). Baseline plasma catalase activity was measured in SURGENE (n = 120) and GENEDIAB (n = 391) participants. RESULTS: The A allele of rs7947841 was associated with the prevalence of incipient (OR 2.79, 95% CI 1.21, 6.24, p = 0.01) and established or advanced nephropathy (OR 5.72, 95% CI 1.62, 22.03, p = 0.007), and with the incidence of renal events, which were defined as new cases of microalbuminuria or progression to a more severe stage of nephropathy during follow-up (HR 1.82, 95% CI 1.13, 2.81, p = 0.01) in SURGENE participants. The same risk allele was associated with incipient nephropathy (OR 3.13, 95% CI 1.42, 7.24, p = 0.004) and with the incidence of end-stage renal disease (ESRD) (HR 2.11, 95% CI 1.23, 3.60, p = 0.008) in GENEDIAB participants. In both cohorts, the risk allele was associated with lower catalase activity. Associations with incipient and established or advanced nephropathy were confirmed in the replication cohort. CONCLUSIONS/INTERPRETATION: CAT variants were associated with the prevalence and incidence of diabetic nephropathy and ESRD in type 1 diabetic patients. Our results confirm the protective role of catalase against oxidative stress in the kidney.
Assuntos
Catalase/genética , Nefropatias Diabéticas/enzimologia , Nefropatias Diabéticas/genética , Frequência do Gene , Falência Renal Crônica/enzimologia , Falência Renal Crônica/genética , Estresse Oxidativo/genética , Polimorfismo de Nucleotídeo Único , Adulto , Bélgica , Brasil , Catalase/metabolismo , Estudos Transversais , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/fisiopatologia , Feminino , Seguimentos , França , Variação Genética , Taxa de Filtração Glomerular , Humanos , Incidência , Falência Renal Crônica/metabolismo , Falência Renal Crônica/fisiopatologia , Masculino , Polimorfismo de Nucleotídeo Único/genética , Prevalência , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: To investigate gene expression of podocyte-specific proteins in urine of diabetes and prediabetes subjects and the association of these proteins with albuminuria. METHODS: Fifteen controls, 19 prediabetes, and 67 diabetes subjects were included. Messenger RNA of nephrin, podocin, podocalyxin, synaptopodin, TRPC6, alpha-actinin-4, and TGF-ß1 were measured using RT-PCR. Podocyte marker expression was correlated with albuminuria, glycemic control, and renal function. The diagnostic performance of the genes used to detect increased albuminuria was assessed using ROC curves and Poisson regressions. RESULTS: Podocyte marker expression was significantly higher in diabetic subjects. Urinary nephrin was correlated with increasing levels of albuminuria; risk of albuminuria increased by 20% for every one-unit increase in the log10 of nephrin mRNA. Nephrinuria was found in 53%, 71%, and 90% of normo-, micro-, and macroalbuminuric diabetes subjects, respectively (p = 0.023). Urinary nephrin, podocalyxin, TRPC6, podocin, and alpha actinin-4 were correlated with glycemic control and albuminuria but not with renal function. CONCLUSIONS: Diabetes subjects had higher urinary mRNA levels of podocyte proteins than nondiabetic subjects, even the normoalbuminuric patients. Nephrinuria was correlated with diabetic nephrophathy stage and predicted pathological albuminuria. Urinary mRNA levels of podocyte markers of prediabetic subjects did not differ from controls.
Assuntos
Glicemia/metabolismo , Diabetes Mellitus/metabolismo , Nefropatias Diabéticas/metabolismo , Podócitos/metabolismo , Proteinúria/metabolismo , Proteoma/metabolismo , RNA Mensageiro/urina , Adulto , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Uncoupling protein 2 (UCP2) is a mitochondrial transporter present in the inner membrane of mitochondria, and it uncouples substrate oxidation from ATP synthesis, thereby dissipating the membrane potential energy and consequently decreasing ATP production by mitochondrial respiratory chain. As a consequence of the uncoupling, UCP2 decreases the reactive oxygen species (ROS) formation by mitochondria. ROS overproduction is related to diabetic retinopathy (DR), a chronic complication of diabetes mellitus (DM). Recently, our group reported that the -866A/55Val/Ins haplotype (-866G/A, Ala55Val and Ins/Del polymorphisms) of the UCP2 gene was associated with increased risk for DR in patients with DM. The purpose of this study was to analyze the effect of this haplotype on UCP2 gene expression in human retina. In addition, MnSOD2 gene expression was also investigated according to different UCP2 haplotypes. This cross-sectional study included 188 cadaveric cornea donors. In a subset of 91 retinal samples differentiated according to the presence of the mutated UCP2 haplotype and risk alleles of the -866G/A and Ins/Del polymorphisms, UCP2 and MnSOD2 gene expressions were measured by semi-quantitative RT-qPCR. Mutated UCP2 haplotype carriers (homozygous + heterozygous) had a lower UCP2 gene expression than reference haplotype carriers (8.4 ± 7.6 vs. 18.8 ± 23.7 arbitrary units; P = 0.046). Accordingly, UCP2 gene expression was decreased in -866A carriers when compared with G/G carriers (P = 0.010). UCP2 gene expression did not differ between Ins allele carriers and Del/Del carriers (P = 0.556). Interestingly, subjects carrying the heterozygous UCP2 haplotype showed increased MnSOD2 gene expression (P = 0.025). This is the first report suggesting that the presence of the -866A/55Val/Ins haplotype is associated with decreased UCP2 gene expression in human retina. Possibly, MnSOD2 expression might influence the UCP2 effect in the protection against oxidative stress.
Assuntos
Retinopatia Diabética/genética , Regulação da Expressão Gênica/fisiologia , Canais Iônicos/genética , Proteínas Mitocondriais/genética , Polimorfismo Genético , Idoso , Estudos Transversais , Primers do DNA/química , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Feminino , Haplótipos , Humanos , Mutação INDEL/genética , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Superóxido Dismutase/genética , Doadores de Tecidos , Proteína Desacopladora 2RESUMO
BACKGROUND: Oxidative stress is recognized as a major pathogenic factor of cellular damage caused by hyperglycemia. NOX/NADPH oxidases generate reactive oxygen species and NOX1, NOX2 and NOX4 isoforms are expressed in kidney and require association with subunit p22phox (encoded by the CYBA gene). Increased expression of p22phox was described in animal models of diabetic nephropathy. In the opposite direction, glutathione is one of the main endogenous antioxidants whose plasmatic concentrations were reported to be reduced in diabetes patients. The aim of the present investigation was to test whether functional single nucleotide polymorphisms (SNPs) in genes involved in the generation of NADPH-dependent O2â¢â» (-675 T â A in CYBA, unregistered) and in glutathione metabolism (-129 C â T in GCLC [rs17883901] and -65 T â C in GPX3 [rs8177412]) confer susceptibility to renal disease in type 1 diabetes patients. METHODS: 401 patients were sorted into two groups according to the presence (n = 104) or absence (n = 196) of overt diabetic nephropathy or according to glomerular filtration rate (GFR) estimated by Modification of Diet in Renal Disease (MDRD) equation: ≥ 60 mL (n = 265) or < 60 mL/min/1.73 m² (n = 136) and were genotyped. RESULTS: No differences were found in the frequency of genotypes between diabetic and non-diabetic subjects. The frequency of GFR < 60 mL/min was significantly lower in the group of patients carrying CYBA genotypes T/A+A/A (18.7%) than in the group carrying the T/T genotype (35.3%) (P = 0.0143) and the frequency of GFR < 60 mL/min was significantly higher in the group of patients carrying GCLC genotypes C/T+T/T (47.1%) than in the group carrying the C/C genotype (31.1%) (p = 0.0082). Logistic regression analysis identified the presence of at least one A allele of the CYBA SNP as an independent protection factor against decreased GFR (OR = 0.38, CI95% 0.14-0.88, p = 0.0354) and the presence of at least one T allele of the GCLC rs17883901 SNP as an independent risk factor for decreased GFR (OR = 2.40, CI95% 1.27-4.56, p = 0.0068). CONCLUSIONS: The functional SNPs CYBA -675 T â A and GCLC rs17883901, probably associated with cellular redox imbalances, modulate the risk for renal disease in the studied population of type 1 diabetes patients and require validation in additional cohorts.
Assuntos
Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/genética , Glutamato-Cisteína Ligase/genética , Glutationa Peroxidase/genética , NADPH Oxidases/genética , Adulto , Estudos de Casos e Controles , Domínio Catalítico/genética , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras GenéticasRESUMO
BACKGROUND AND OBJECTIVE: Uncoupling protein 2 (UCP2) plays a role in controlling reactive oxygen species (ROS) production by mitochondria. As ROS overproduction is related to diabetic retinopathy (DR), UCP2 gene polymorphisms might be involved in the development of this complication. We investigated whether the -866G/A (rs659366), Ala55Val (rs660339) and 45 bp insertion/deletion (Ins/Del) polymorphisms in the UCP2 gene might be associated with proliferative DR (PDR). DESIGN AND METHODS: In this case-control study, we analysed 501 type 2 diabetic patients (242 patients with PDR and 259 subjects without any degree of DR) and 196 type 1 diabetic patients (85 cases with PDR and 111 without DR). Haplotypes constructed from the combination of the three UCP2 polymorphisms were inferred using a Bayesian statistical method. RESULTS: In the type 2 diabetic group, multivariate analyses confirmed that the haplotype [A Val Ins] was an independent risk factor for PDR when present in one [adjusted odds ratio (aOR) = 2.12; P = 0.006], at least one (aOR = 2.75; P = 0.00001), or two copies (aOR = 5.30; P = 0.00001), suggesting an additive model of inheritance. Nevertheless, in type 1 diabetic patients, the association of this haplotype with PDR was confirmed only when it was present in at least one (aOR = 2.68; P = 0.014) or two copies (aOR = 6.02; P = 0.005). CONCLUSIONS: The haplotype [A Val Ins] seems to be an important risk factor associated with PDR in both type 2 and 1 diabetic groups.
Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/genética , Canais Iônicos/genética , Proteínas Mitocondriais/genética , Polimorfismo Genético , Idoso , Teorema de Bayes , Estudos de Casos e Controles , Retinopatia Diabética/complicações , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Mutação INDEL , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Proteína Desacopladora 2RESUMO
BACKGROUND: Urinary albumin is the main parameter employed to diagnose diabetic nephropathy (DN). The exclusion of bacteriuria has been recommended at the time of DN diagnosis. This approach has been debated and information on this suggestion in patients with diabetes is scarce. The present case-control study was conducted to investigate the interference of bacteriuria in the interpretation of urinary albumin measurements in random urine samples of diabetic patients. METHODS: Urinary albumin concentration (UAC) was measured in random urine samples twice in diabetic patients with and without bacteriuria (> or =10(5) colony-forming units/mL). Cases (n = 81) were defined as patients who had baseline UAC measurement in the presence of bacteriuria and had the second UAC measured in a sterile urine sample. Controls (n = 80) had the two UAC measured in sterile urine specimens. RESULTS: Baseline UAC was not different between case [15.4 (1.5-2148) mg/L] and control groups [14.2 (1.5-1292) mg/L; P = 0.24], nor was the proportion of patients with normo-, micro- and macroalbuminuria. In cases, UAC measurements in the presence of bacteriuria and in sterile urine specimens were not different [15.4 (1.5-2148) versus 13.7 (1.5-2968) mg/L; P = 0.14)], nor was the proportion of normo- (51.9% versus 61.5%), micro- (40.7% versus 32.1%) and macroalbuminuria (7.4% versus 6.4%; P = 0.46). In the control group, UAC values were also not different in the two urine samples: [14.2 (1.5-1292) versus 9.7 (1.5-1049) mg/L, P = 0.22]. CONCLUSIONS: The presence of bacteriuria does not interfere significantly with urinary albumin measurements and its exclusion is not necessary to diagnose DN.
Assuntos
Albuminúria/diagnóstico , Nefropatias Diabéticas/diagnóstico , Urina/química , Urina/microbiologia , Adulto , Idoso , Albuminúria/etiologia , Albuminúria/microbiologia , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/microbiologia , Diabetes Mellitus Tipo 2/urina , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/urina , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: Efficacy and safety of the glucagon-like peptide 1 (GLP-1) analog oral semaglutide and the sodium-glucose cotransporter 2 inhibitor empagliflozin were compared in patients with type 2 diabetes uncontrolled on metformin. RESEARCH DESIGN AND METHODS: Patients were randomized to once-daily open-label treatment with oral semaglutide 14 mg (n = 412) or empagliflozin 25 mg (n = 410) in a 52-week trial. Key end points were change from baseline to week 26 in HbA1c (primary) and body weight (confirmatory secondary). Two estimands addressed efficacy-related questions: treatment policy (regardless of trial product discontinuation or rescue medication) and trial product (on trial product without rescue medication) in all randomized patients. RESULTS: Four hundred (97.1%) patients in the oral semaglutide group and 387 (94.4%) in the empagliflozin group completed the trial. Oral semaglutide provided superior reductions in HbA1c versus empagliflozin at week 26 (treatment policy -1.3% vs. -0.9% [-14 vs. -9 mmol/mol], estimated treatment difference [ETD] -0.4% [95% CI -0.6, -0.3] [-5 mmol/mol (-6, -3)]; P < 0.0001). The treatment difference in HbA1c significantly favored oral semaglutide at week 26 for the trial product estimand (-1.4% vs. -0.9% [-15 vs. -9 mmol/mol], ETD -0.5% [95% CI -0.7, -0.4] [-6 mmol/mol (-7, -5)]; P < 0.0001) and at week 52 for both estimands (P < 0.0001). Superior weight loss was not confirmed at week 26 (treatment policy), but oral semaglutide was significantly better than empagliflozin at week 52 (trial product -4.7 vs. -3.8 kg; P = 0.0114). Gastrointestinal adverse events were more common with oral semaglutide. CONCLUSIONS: Oral semaglutide was superior to empagliflozin in reducing HbA1c but not body weight at 26 weeks in patients with type 2 diabetes uncontrolled on metformin. At week 52, HbA1c and body weight (trial product estimand) were significantly reduced versus empagliflozin. Oral semaglutide was well tolerated within the established safety profile of GLP-1 receptor agonists.
Assuntos
Compostos Benzidrílicos/administração & dosagem , Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Glucosídeos/administração & dosagem , Hipoglicemiantes/administração & dosagem , Metformina/administração & dosagem , Administração Oral , Adulto , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Hemoglobinas Glicadas/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Redução de Peso/efeitos dos fármacosRESUMO
AIMS: The aim of this study was to investigate a miRNA expression profile in type 1 diabetes mellitus (T1DM) patients with DKD (cases) or without this complication (controls). METHODS: Expression of 48 miRNAs was screened in plasma of 58 T1DM patients (23 controls, 18 with moderate DKD, and 17 with severe DKD) using TaqMan Low Density Array cards (Thermo Fisher Scientific). Then, five of the dysregulated miRNAs were selected for validation in an independent sample of 10 T1DM controls and 19 patients with DKD (10 with moderate DKD and 9 with severe DKD), using RT-qPCR. Bioinformatic analyses were performed to explore the putative target genes and biological pathways regulated by the validated miRNAs. RESULTS: Among the 48 miRNAs investigated in the screening analysis, 9 miRNAs were differentially expressed between DKD cases and T1DM controls. Among them, the five most dysregulated miRNAs were chosen for validation in an independent sample. In the validation sample, miR-21-3p and miR-378-3p were confirmed to be upregulated in patients with severe DKD, while miR-16-5p and miR-29a-3p were downregulated in this group compared to T1DM controls and patients with moderate DKD. MiR-503-3p expression was not validated. Bioinformatic analyses indicate that the four validated miRNAs regulate genes from PI3K/Akt, fluid shear stress and atherosclerosis, AGE-RAGE, TGF-ß1, and relaxin signaling pathways. CONCLUSIONS: Our study found four miRNAs differentially expressed in patients with severe DKD, providing significant information about the biological pathways in which they are involved.
Assuntos
Diabetes Mellitus Tipo 1/sangue , Nefropatias Diabéticas/sangue , MicroRNAs/sangue , Adolescente , Adulto , Estudos de Casos e Controles , Biologia Computacional/métodos , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/genética , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , MicroRNAs/genética , Análise em Microsséries , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/genética , Adulto JovemRESUMO
The identification of risk factors for acute rejection (AR) may lead to strategies to improve success of kidney transplantation. Ectonucleotidases are ectoenzymes that hydrolyze extracellular nucleotides into nucleosides, modulating the purinergic signaling. Some members of the Ectonucleotidase family have been linked to transplant rejection processes. However, the association of Ectonucleotide Pyrophosphatase / Phosphodiesterase 1 (ENPP1) with AR has not yet been evaluated. The aim of this study was to evaluate the association between the K121Q polymorphism of ENPP1 gene and AR in kidney transplant patients. We analyzed 449 subjects without AR and 98 with AR from a retrospective cohort of kidney transplant patients from Southern Brazil. K121Q polymorphism was genotyped using allelic discrimination-real-time PCR. Cox regression analysis was used to evaluate freedom of AR in kidney transplant patients according to genotypes. Q allele frequency was 17.6% in recipients without AR and 21.9% in those with AR (P = 0.209). Genotype frequencies of the K121Q polymorphism were in Hardy-Weinberg equilibrium in non-AR patients (P = 0.70). The Q/Q genotype (recessive model) was associated with AR (HR = 2.83, 95% CI 1.08-7.45; P = 0.034) after adjusting for confounders factors. Our findings suggest a novel association between the ENPP1 121Q/Q genotype and AR in kidney transplant recipients.
Assuntos
Rejeição de Enxerto/enzimologia , Rejeição de Enxerto/genética , Transplante de Rim/efeitos adversos , Diester Fosfórico Hidrolases/genética , Pirofosfatases/genética , Doença Aguda , Substituição de Aminoácidos , Brasil , Estudos de Casos e Controles , Estudos de Coortes , Frequência do Gene , Genes Recessivos , Estudos de Associação Genética , Humanos , Modelos Genéticos , Polimorfismo de Nucleotídeo Único , Estudos RetrospectivosRESUMO
BACKGROUND: The enzyme 11-beta hydroxysteroid dehydrogenase type 1 (HSD11B1) converts inactive cortisone to active cortisol in a process mediated by the enzyme hexose-6-phosphate dehydrogenase (H6PD). The generation of cortisol from this reaction may increase intra-abdominal cortisol levels and contribute to the physiopathogenesis of obesity and metabolic syndrome (MetS). The relationship of HSD11B1 rs45487298 and H6PD rs6688832 polymorphisms with obesity and MetS was studied. We also studied how HSD11B1 abdominal subcutaneous (SAT) and visceral adipose tissue (VAT) gene expression is related to body fat distribution. METHODS: Rates of obesity and MetS features were cross-sectionally analyzed according to these polymorphisms in 1006 Brazilian white patients with type 2 diabetes (T2DM). Additionally, HSD11B1 expression was analyzed in VAT and SAT in a different cohort of 28 participants with and without obesity who underwent elective abdominal operations. RESULTS: Although polymorphisms of the two genes were not individually associated with MetS features, a synergistic effect was observed between both. Carriers of at least three minor alleles exhibited lower BMI compared to those with two or fewer minor alleles adjusting for gender and age (27.4 ± 4.9 vs. 29.3 ± 5.3 kg/m2; P = 0.005; mean ± SD). Obesity frequency was also lower in the first group (24.4% vs. 41.6%, OR = 0.43, 95% CI 0.21-0.87; P = 0.019). In the second cohort of 28 subjects, HSD11B1 gene expression in VAT was inversely correlated with BMI (r = - 0.435, P = 0.034), waist circumference (r = - 0.584, P = 0.003) and waist-to-height ratio (r = - 0.526, P = 0.010). CONCLUSIONS: These polymorphisms might interact in the protection against obesity in T2DM individuals. Obese individuals may have decreased intra-abdominal VAT HSD11B1 gene expression resulting in decreasing intra-abdominal cortisol levels as a compensatory mechanism against central and general adiposity.
RESUMO
AIMS: To investigate a miRNA expression profile in plasma of type 1 diabetes (T1DM) patients and control subjects and analyze the putative pathways involved. METHODS: Expressions of 48 miRNAs were analyzed in plasma of 33 T1DM patients and 26 age-and-gender-matched controls using Stem-loop RT-PreAmp PCR and TaqMan Low Density Arrays (Thermo Fisher Scientific). Five dysregulated miRNAs were then chosen for validation in an independent sample of 27 T1DM patients and 14 controls, using RT-qPCR. Bioinformatic analyses were performed to determine in which pathways these miRNAs are involved. RESULTS: Nine miRNAs were differentially expressed between recently-diagnosed T1DM patients (<5 years of diagnosis) and controls. No differences were observed between patients with ≥5â¯years of diagnosis and controls. After validation in an independent sample of T1DM patients, miR-103a-3p, miR-155-5p, miR-200a-3p, and miR-210-3p were confirmed as being upregulated in recently-diagnosed T1DM patients compared with controls or patients with ≥5â¯years of diagnosis. Moreover, miR-146a-5p was downregulated in recently-diagnosed T1DM patients compared with the other groups. These five miRNAs regulate several genes from innate immune system-, MAPK-, apoptosis-, insulin- and cancer-related pathways. CONCLUSION: Five miRNAs are dysregulated in recently-diagnosed T1DM patients and target several genes involved in pathways related to T1DM pathogenesis, thus representing potential T1DM biomarkers.
Assuntos
Biologia Computacional/métodos , Diabetes Mellitus Tipo 1/genética , MicroRNAs/metabolismo , Adulto , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Humanos , Masculino , Adulto JovemRESUMO
AIMS: Type 1 diabetes mellitus (T1DM) is characterized by severe autoimmune destruction of pancreatic beta-cells. The triggering of autoimmunity against beta-cells is probably caused by a combination of environmental and genetic risk factors. Even though much is known about the genetic of T1DM, more information is needed to completely unravel this tangled disease. MicroRNAs (miRNAs) are a class of small noncoding RNAs molecules that negatively regulate gene expression by inducing target mRNA cleavage or by inhibiting protein translation. Abnormal miRNA expressions have been described in autoimmune diseases and T1DM. Polymorphisms in genes codifying miRNAs may alter the expression of the corresponding miRNA and, thus, confer susceptibility for a given disease. Therefore, the aim of this study was to investigate whether polymorphisms in genes encoding miR-155, miR-146a, and miR-375 are associated with T1DM. METHODS: Frequencies of the miRNA-146a rs2910164, miRNA-155 rs767649 and miRNA-375 rs6715345 polymorphisms were analyzed in 490 T1DM patients and in 469 nondiabetic subjects. RESULTS: The miR-146a rs2910164 and miR-155 rs767649 polymorphisms were associated with protection for T1DM, and the strongest association was observed for the dominant model [odds ratio (OR) = 0.557 95% CI 0.355-0.874 and OR = 0.508, 95% CI 0.265-0.973, respectively, after adjustment for age, ethnicity, and risk HLA loci]. However, miR-375 rs6715345 frequencies did not differ between cases and controls. CONCLUSION: MiR-146a rs2910164 and miR-155 rs767649 polymorphisms were associated with protection for T1DM.
Assuntos
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/prevenção & controle , Estudos de Associação Genética/métodos , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Alelos , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
The intestinal fatty-acid binding protein-2 (FABP2) gene codes a protein responsible for the absorption of long-chain fatty acids. To test whether FABP2 is a candidate gene for renal disease in patients with type 2 diabetes, a functional A54T polymorphism was genotyped in 1,042 Brazilians with type 2 diabetes. Patients were classified as having normoalbuminuria (urinary albumin excretion [UAE] <20 microg/min; n = 529), microalbuminuria (UAE 20-199 microg/min; n = 217), or proteinuria (UAE >199 microg/min; n = 160). Patients with end-stage renal disease (ESRD) (n = 136) were also included. The prevalence of the TT genotype was higher in patients with renal involvement compared with those with normoalbuminuria (odds ratio [95% CI] 2.4 [1.1-5.4]) following adjustment for type 2 diabetes duration, BMI, hypertension, A1C, and cholesterol levels. The risk was similar considering different stages of renal involvement. In a second independent patient sample (483 type 2 diabetic Caucasians residing in Massachusetts), a significant association was also observed between the TT genotype and proteinuria or ESRD (2.7 [1.0-7.3]; P = 0.048). This study thus provides evidence that FABP2 confers susceptibility to renal disease in type 2 diabetic patients.
Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/genética , Proteínas de Ligação a Ácido Graxo/genética , Predisposição Genética para Doença/genética , Polimorfismo Genético/genética , Brasil , Haplótipos , Humanos , Massachusetts , Razão de ChancesRESUMO
OBJECTIVE: To evaluate the 24-h blood pressure profile in normoalbuminuric type 2 diabetic patients. RESEARCH DESIGN AND METHODS: A cross-sectional study was conducted in 90 type 2 diabetic patients with a urinary albumin excretion rate (UAER) <20 microg/min on two occasions, 6 months apart (immunoturbidimetry). Patients underwent clinical and laboratory evaluations. Ambulatory blood pressure monitoring and echocardiograms were also performed. RESULTS: UAER was found to correlate positively with systolic doctor's office blood pressure measurements (r = 0.243, P = 0.021) and ambulatory blood pressure (24 h: r = 0.280, P = 0.008) and left ventricular posterior wall thickness (r = 0.359, P = 0.010). Patients were divided into four groups according to UAER (<5, > or =5-10, > or =10-15, and > or =15-20 microg/min). Systolic blood pressure parameters for the 1st, 2nd, 3rd, and 4th groups, respectively, were 123.0 +/- 10.6, 132.5 +/- 15.0, 139.0 +/- 23.4, and 130.7 +/- 8.0 mmHg for 24-h blood pressure (ANOVA P = 0.004) and 48.4 +/- 6.0, 54.5 +/- 11.2, 58.8 +/- 15.6, and 57.6 +/- 8.0 mmHg for 24-h pulse pressure (ANOVA P = 0.003). A progressive increase in the prevalence of diabetic retinopathy was observed from the 1st to the 4th UAER group: 27.3, 43.8, 45.5, and 66.7% (P = 0.029 for trend). CONCLUSIONS: In type 2 diabetic patients, UAER in the normoalbuminuric range is positively associated with systolic ambulatory blood pressure indexes, left ventricular posterior wall thickness, and diabetic retinopathy, suggesting that intensive blood pressure treatment may prevent diabetes complications in these patients.
Assuntos
Albuminúria/urina , Pressão Sanguínea/fisiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Hipertensão/urina , Análise de Variância , Estudos Transversais , Diabetes Mellitus Tipo 2/urina , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , FumarRESUMO
OBJECTIVE: To investigate the presence of maternal and paternal history of type 2 diabetes mellitus (DM) in relatives of 644 type 2 diabetic patients from Southern Brazil, and also to evaluate its influence on the clinical characteristics of this disease. PATIENTS AND METHODS: Familial history of type 2 DM was investigated by a questionnaire. The maternal and paternal history was investigated over two generations. Complete data sets on familial history were obtained from 396 patients. RESULTS: In general, 76.6% of the patients reported at least one first-degree affected relative. Besides, 31.6% of the patients reported a maternal history of type 2 DM and 12.6% reported a paternal history. Patients with maternal and/or paternal history presented a lower age at type 2 DM diagnosis when compared to patients without familial history. In addition, patients with only paternal history presented a higher frequency of hypertension than patients with no familial history. CONCLUSIONS: This study suggests that there is a significant maternal effect in the transmission of type 2 DM in Southern Brazil, and that most of the clinical characteristics of this disease do not differ between patients with or without familial history of type 2 DM.
Assuntos
Diabetes Mellitus Tipo 2/genética , Pai , Mães , Adulto , Idade de Início , Albuminúria/urina , População Negra/genética , Glicemia/análise , Brasil/etnologia , Diabetes Mellitus Tipo 2/etnologia , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Anamnese , Pessoa de Meia-Idade , Linhagem , Gravidez , População Branca/genéticaRESUMO
The daily use of aspirin in patients with type 2 diabetes mellitus (DM2) reduces significantly cardiovascular events (CVE). In the absence of contraindications, American Diabetes Association (ADA) recommends the use of aspirin to all DM2 patients older than 40 years of age. To evaluate aspirin use among 636 out patients with DM2 who participate in a regional multicenter study in Southern Brazil, a standard questionnaire was used. Patients also underwent a physical examination and laboratorial tests. All patients were older than 40 years (mean 58 +/- 11 years old; 42% male) and by ADA guidelines most of them should be using aspirin. However, only 177 (27.5%) were on this medication. The use of aspirin was higher when any CVE were present. However, the percentage of users was still below the expected, not even reaching 50%. In conclusion, even though the use of aspirin is greater in patients with CVE, and its benefits are well documented, it is still underutilized. Strategies to enhance the use of aspirin should be developed to reduce the morbidity and mortality from cardiovascular diseases in patients with DM2.