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1.
Internist (Berl) ; 55(10): 1149-56, 2014 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-25204533

RESUMO

The use of thyroid-stimulating hormone (TSH) testing in routine laboratory screening and testing of TSH before administration of contrast medium, resulted in an increased number of incidentally detected elevated TSH levels. In the case of slightly increased values in asymptomatic patients, repeated measurement of TSH is recommended for confirmation. Confirmed elevated TSH levels should lead to additional measurements of the peripheral thyroid hormones, determination of thyroid autoantibodies and performance of thyroid gland ultrasound examination. The most common reasons for acquired subclinical and overt hypothyroidism are autoimmune diseases of the thyroid gland and in many cases substitution therapy with levothyroxine is then necessary. In subclinical hypothyroidism it remains unclear at which TSH levels the initiation of substitution therapy makes sense. In the case of simultaneously elevated peripheral thyroid hormones rare diseases, such as secondary hyperthyroidism and thyroid hormone resistance should be considered.


Assuntos
Erros de Diagnóstico/prevenção & controle , Hipotireoidismo/sangue , Hipotireoidismo/diagnóstico , Achados Incidentais , Programas de Rastreamento/métodos , Tireotropina/sangue , Biomarcadores/sangue , Diagnóstico Diferencial , Humanos
3.
Horm Metab Res ; 46(4): 283-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24198220

RESUMO

The concentration of serum testosterone is mainly regulated by the testicular function, which is under control of the central hypothalamic-pituitary-gonadal axis. A certain amount of testosterone is converted into ß-estradiol by adipose tissue. Obesity in men is often associated with decreased androgen levels. The aim of the present study was to examine the effect of caloric restriction on serum testosterone levels in obese men. Dietary intervention study was performed with a very low calorie diet (800 kcal/d) for 12 weeks. Thirteen obese human male subjects (median body mass index: 42.7 kg/m2) were included. Body composition was assessed by impedance analysis. Insulin sensitivity was estimated by leptin-to-adiponectin ratio (LAR). Testosterone (T), ß-estradiol, albumin, sex hormone-binding globulin (SHBG), LH, and FSH serum concentrations were measured by enzyme immunoassays. Statistical analysis was performed on baseline and values after 3 months. Caloric restriction significantly increased total testosterone (6.97 nmol/l to 13.21 nmol/l; p=0.001) and SHBG (22.11 nmol/l to 42.12 nmol/l; p=0.001) concentrations in serum. This is caused by a significant improvement of the testicular function (LH/T: 0.36-0.20; p=0.005) and a significant reduction of the T/ß-estradiol conversion rate (73.59-104.29; p=0.003). There was a significant negative correlation of improvement of testicular function and LAR (rs=-0.683 (p=0.042)). In obese men caloric restriction significantly increases the serum testosterone concentration. This is achieved by 2 distinct mechanisms, that is, improvement of testicular function and reduced conversion of testosterone to ß-estradiol by aromatase activity of the adipose tissue.


Assuntos
Restrição Calórica , Obesidade/sangue , Testosterona/sangue , Adiponectina/sangue , Adulto , Estradiol/sangue , Humanos , Resistência à Insulina , Leptina/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Testículo/fisiopatologia
4.
Age (Dordr) ; 35(5): 1881-97, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23160735

RESUMO

The insulin receptor substrates (IRS) are adapter proteins mediating insulin's and IGF1's intracellular effects. Recent data suggest that IRS2 in the central nervous system (CNS) is involved in regulating fuel metabolism as well as memory formation. The present study aims to specifically define the role of chronically increased IRS2-mediated signal transduction in the CNS. We generated transgenic mice overexpressing IRS2 specifically in neurons (nIRS2 (tg)) and analyzed these in respect to energy metabolism, learning, and memory. Western blot (WB) analysis of nIRS2 (tg) brain lysates revealed increased IRS2 downstream signaling. Histopathological investigation of nIRS2 (tg) mice proved unaltered brain development and structure. Interestingly, nIRS2 (tg) mice showed decreased voluntary locomotoric activity during dark phase accompanied with decreased energy expenditure (EE) leading to increased fat mass. Accordingly, nIRS2 (tg) mice develop insulin resistance and glucose intolerance during aging. Exploratory behavior, motor function as well as food and water intake were unchanged in nIRS2 (tg) mice. Surprisingly, increased IRS2-mediated signals did not change spatial working memory in the T-maze task. Since FoxO1 is a key mediator of IRS2-transmitted signals, we additionally generated mice expressing a dominant negative mutant of FoxO1 (FoxO1DN) specifically in neurons. This mutant mimics the effect of increased IRS2 signaling on FoxO-mediated transcription. Interestingly, the phenotype observed in nIRS2 (tg) mice was not present in FoxO1DN mice. Therefore, increased neuronal IRS2 signaling causes decreased locomotoric activity in the presence of unaltered exploratory behavior and motor coordination that might lead to increased fat mass, insulin resistance, and glucose intolerance during aging independent of FoxO1-mediated transcription.


Assuntos
Envelhecimento/metabolismo , Encéfalo/metabolismo , DNA/genética , Regulação da Expressão Gênica no Desenvolvimento , Intolerância à Glucose/genética , Proteínas Substratos do Receptor de Insulina/genética , Resistência à Insulina , Animais , Southern Blotting , Encéfalo/fisiopatologia , Calorimetria Indireta , Células Cultivadas , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Fibroblastos/metabolismo , Genótipo , Intolerância à Glucose/metabolismo , Intolerância à Glucose/fisiopatologia , Imuno-Histoquímica , Proteínas Substratos do Receptor de Insulina/biossíntese , Locomoção/fisiologia , Camundongos
5.
J Mol Med (Berl) ; 90(10): 1145-60, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22411022

RESUMO

The role of mitochondrial dysfunction in the development of insulin resistance and type 2 diabetes remains controversial. In order to specifically define the relationship between insulin receptor (InsR) signaling, insulin resistance, hyperglycemia, hyperlipidemia and mitochondrial function, we analyzed mitochondrial performance of insulin-sensitive, slow-oxidative muscle in four different mouse models. In obese but normoglycemic ob/ob mice as well as in obese but diabetic mice under high-fat diet, mitochondrial performance remained unchanged even though intramyocellular diacylglycerols (DAGs), triacylglycerols (TAGs), and ceramides accumulated. In contrast, in muscle-specific InsR knockout (MIRKO) and streptozotocin (STZ)-treated hypoinsulinemic, hyperglycemic mice, levels of mitochondrial respiratory chain complexes and mitochondrial function were markedly reduced. In STZ, but not in MIRKO mice, this was caused by reduced transcription of mitochondrial genes mediated via decreased PGC-1α expression. We conclude that mitochondrial dysfunction is not causally involved in the pathogenesis of obesity-associated insulin resistance under normoglycemic conditions. However, obesity-associated type 2 diabetes and accumulation of DAGs or TAGs is not associated with impaired mitochondrial function. In contrast, chronic hypoinsulinemia and hyperglycemia as seen in STZ-treated mice as well as InsR deficiency in muscle of MIRKO mice lead to mitochondrial dysfunction. We postulate that decreased mitochondrial mass and/or performance in skeletal muscle of non-diabetic, obese or type 2 diabetic, obese patients observed in clinical studies must be explained by genetic predisposition, physical inactivity, or other still unknown factors.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Transporte de Elétrons , Resistência à Insulina , Insulina/fisiologia , Mitocôndrias Musculares/metabolismo , Obesidade/metabolismo , Transdução de Sinais , Animais , Autofagia , Glicemia , Carnitina O-Palmitoiltransferase/metabolismo , Diabetes Mellitus Experimental/sangue , Dieta Hiperlipídica/efeitos adversos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Expressão Gênica , Glucosilceramidas/metabolismo , Metabolismo dos Lipídeos , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Mitocôndrias Musculares/enzimologia , Mitocôndrias Musculares/fisiologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Obesidade/sangue , Obesidade/etiologia , Estresse Oxidativo , Consumo de Oxigênio , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Estreptozocina , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição
6.
Horm Metab Res ; 44(6): 465-70, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22438213

RESUMO

Inflammatory mechanisms are involved in the pathogenesis of type 2 diabetes with interleukin (IL)-6 being particularly important. While long term exercise has been shown to be associated with reduction in IL-6 serum levels in several reports, the discussion on the effect of dietary intervention on IL-6 serum levels is controversial. In the present study, we aimed to investigate the effect of weight loss due to a very low calorie diet (VLCD) on insulin sensitivity and IL-6 serum levels in nondiabetic obese human individuals. 10 patients with obesity were examined during 12 weeks of a VLCD (800 kcal/d). Body composition was measured by impedance analysis. Blood samples were taken before, during, and after the dietary intervention. Leptin, adiponectin, and IL-6 serum levels were measured by ELISA. The body weight decreased significantly from 123.9±6.2-103.5±5.6 kg with a significant reduction in body fat content (43.2±2.3-36.1±3.1%). Leptin levels exhibited a significant decrease from 56.8±5.6-27.9±5.6 ng/ml while adiponectin levels increased significantly from 7.5±0.9-10.6±1.1 µg/ml. Thereby the leptin-to-adiponectin ratio, a novel marker for insulin sensitivity, significantly improved. Mean IL-6 serum concentrations were within the normal range (3.2±0.8 pg/ml) before the study and were not significantly altered by the nutritional therapy. Despite improvement of insulin sensitivity, IL-6 serum levels did not change throughout the study period, suggesting that in nondiabetic obese human subjects IL-6 might have only a minor role in the impairment of insulin sensitivity.


Assuntos
Restrição Calórica , Resistência à Insulina , Interleucina-6/sangue , Obesidade/sangue , Obesidade/dietoterapia , Redução de Peso , Adipocinas/sangue , Adulto , Glicemia/metabolismo , Composição Corporal , Peso Corporal , Proteína C-Reativa/metabolismo , Diabetes Mellitus/sangue , Jejum/sangue , Feminino , Humanos , Inflamação/sangue , Inflamação/complicações , Inflamação/patologia , Metabolismo dos Lipídeos , Masculino , Obesidade/complicações , Obesidade/patologia
8.
Exp Clin Endocrinol Diabetes ; 120(6): 340-50, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22187289

RESUMO

BACKGROUND: Recent data suggest that insulin-like growth factor (IGF)-1 resistance in neurons prolongs longevity. In C. elegans this effect is mediated via DAF-16 the ortholog of the mammalian FoxO transcription factors. 3 different FoxO transcription factors (FoxOs) are expressed in rodent CNS: FoxO1, FoxO3a and FoxO6. METHODS: To define whether the different FoxOs are region-, sex- and age-specifically expressed, we analyzed FoxO mRNA levels in different brain regions from 6, 16, 60 and 100 weeks old mice using realtime-PCR. In addition, we fed mice a high fat diet (HFD) to experimentally induce obesity and diabetes and analyzed FoxO mRNA in the different brain regions. RESULTS: Interestingly, FoxO1 was predominantly expressed in the hippocampus whereas FoxO3a was quantitatively the most abundant FoxO in the neocortex. During aging, FoxO1 expression peaked in all brain regions at 16 weeks and FoxO6 showed its highest expression at 60 weeks in the parietal and occipital cortex. In 6 weeks old mice FoxO6 expression was higher in male compared to female mice in the hippocampus and all cortical regions. Surprisingly, in HFD animals FoxO3a was significantly less expressed in the cerebellum and all cortical regions compared to control animals. Even more dramatic, FoxO6 expression dropped about 80% in all brain regions in response to HFD. CONCLUSION: Thus, FoxOs in the CNS showed a highly distinct expression, which in addition was age- and sex-dependent. In contrast to FoxO1, FoxO3a and FoxO6 were specifically diminished in the CNS of HFD animals possibly contributing to the reduced lifespan observed in these animals.


Assuntos
Envelhecimento/genética , Sistema Nervoso Central/metabolismo , Diabetes Mellitus Tipo 2/genética , Fatores de Transcrição Forkhead/genética , Obesidade/genética , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Animais , Células Cultivadas , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Regulação para Baixo/genética , Feminino , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/complicações , Obesidade/metabolismo
9.
Horm Metab Res ; 44(2): 99-104, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22198814

RESUMO

Insulin, insulin-like growth factor-1 (IGF-1), and leptin signaling have been proposed to play an important role in regulating energy homeostasis. In order to specifically address the role of neuronal IGF-1 receptor (IGF-1R) signaling for energy expenditure and metabolism we used conditional mutagenesis. Deletion of one copy of the IGF-1R specifically in post-mitotic neurons (nIGF-1R(+/-) ) does not result in growth retardation or skeletal abnormalities. Interestingly, male nIGF-1R(+/-) mice accumulate less fat mass during aging accompanied with decreased leptin levels compared to wild-type littermates. Furthermore, male nIGF-1R(+/-) mice present with increased locomotor activity and energy expenditure. In contrast, female nIGF-1R(+/-) mice remained nearly unaffected. Circadian pattern of locomotor activity and energy expenditure as well as food and water intake did not change. Consistent with increased locomotor activity, the respiratory quotient was shifted to increased fat oxidation in nIGF-1R(+/-) mice. Surprisingly, serum IGF-1 and IGF-1 binding protein 3 (IGF-BP3) concentrations were decreased in nIGF-1R(+/-) mice despite the presence of normal pituitaries suggesting a functional feedback mechanism via neuronal IGF-1Rs, which regulate serum IGF-1 levels. Thus, we show that neuron-specific IGF-1R deletion in male mice decreases body fat accumulation and increases energy expenditure during aging.


Assuntos
Tecido Adiposo/fisiologia , Envelhecimento/genética , Neurônios/fisiologia , Receptor IGF Tipo 1/genética , Animais , Comportamento Animal/fisiologia , Glicemia/metabolismo , Calorimetria Indireta , Metabolismo Energético , Insulina/metabolismo , Estimativa de Kaplan-Meier , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Receptor IGF Tipo 1/metabolismo
10.
Int J Obes (Lond) ; 35(11): 1450-4, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21285942

RESUMO

In patients with obesity and type 2 diabetes, adipose tissue is infiltrated by macrophages known to alter adipogenesis of mesenchymal precursor cells via secretion of proinflammatory cytokines. Recently, it has been shown that under certain conditions, immune cells can also express wnt-5a, a factor known to inhibit adipogenesis in humans. Therefore, in this study we aimed to investigate whether macrophages affect adipogenesis of mesenchymal precursor cells via wnt-5a. Wnt-5a was found to be expressed in adipose tissue macrophages in obese and type 2 diabetic human subjects in vivo by immunohistochemistry of adipose tissue biopsies. Furthermore, wnt-5a was detectable in circulating CD14(+) blood monocytes of human subjects with obesity and type 2 diabetes on RNA level by real-time PCR. Besides expression analysis in vivo, we also performed functional studies to explore the role of wnt-5a in low-grade inflammation of adipose tissue. In a cell culture experiment, macrophage-conditioned differentiation medium inhibited adipogenesis of 3T3-L1 cells. This inhibitory effect was restored by adding neutralising anti-wnt-5a antibodies. In conclusion, our data indicate that macrophages alter adipogenesis of 3T3-L1 cells not only via classical proinflammatory cytokines, but also via wnt signalling molecules.


Assuntos
Adipócitos/metabolismo , Adipogenia , Tecido Adiposo/patologia , Macrófagos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Obesidade/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Wnt/metabolismo , Adipócitos/patologia , Células Cultivadas , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Obesidade/genética , Obesidade/patologia , Transdução de Sinais , Proteína Wnt-5a
11.
J Dairy Sci ; 94(2): 589-601, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21257028

RESUMO

Malleable protein matrix (MPM) is a unique whey-derived ingredient obtained through a fermentation process using proprietary lactic acid bacteria strains from the Lactobacillus kefiranofaciens species. Because evidence from animal models suggests that MPM decreases serum lipid concentrations, the purpose of the present trial was to assess the hypothesis that MPM exerts lipid-lowering effects in humans. A total of 161 subjects (50% male; age 54.5 ± 9.8 yr, body mass index 26.3 ± 3.6 kg/m(2)) with hypercholesterolemia with baseline low-density lipoprotein cholesterol (LDL-C) levels of 181 ± 30 mg/dL and normal triglyceride (TG) levels (131 ± 55 mg/dL) were randomized to receive MPM (2 × 15 g/d) or matching placebo. A 6-wk run-in phase was followed by a double-blind 12-wk treatment phase after randomization. The data were analyzed on an intention-to-treat basis. The primary outcome measure was the percentage change of LDL-C. The secondary outcome measures were changes in TG and high-density lipoprotein cholesterol concentrations as well as changes in other cardiovascular risk factors. After 12 wk of treatment, the relative TG decrease from baseline reached 9.8%, whereas LDL-C was slightly decreased (by 1.5%) following MPM treatment compared with placebo in the intention-to-treat cohort. The treatment effect on TG reduction was much higher in the subset of subjects having TG levels at baseline of 150 mg/dL or above (n=42), reaching 20.0% compared with placebo. High-density lipoprotein cholesterol concentrations, blood pressure, and fasting blood glucose remained unchanged, whereas a positive treatment effect was seen on hemoglobin A(1c). The MPM product was tolerated well without severe adverse events. In conclusion, MPM has significant TG-lowering properties in subjects with combined hypercholesterolemia and higher TG levels. Its effects on LDL-C concentrations and glucose metabolism deserve further investigation.


Assuntos
Anticolesterolemiantes/uso terapêutico , Produtos Fermentados do Leite , Hipercolesterolemia/tratamento farmacológico , Proteínas do Leite/uso terapêutico , Triglicerídeos/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Método Duplo-Cego , Feminino , Humanos , Hipercolesterolemia/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Resultado do Tratamento , Proteínas do Soro do Leite
12.
J Hum Hypertens ; 25(3): 186-95, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20376075

RESUMO

Metabolic syndrome, a cluster of risk factors that increase the risk of cardiovascular morbidity and mortality, is common in patients with hypertension. Chronic renin-angiotensin-aldosterone system (RAAS) activation, shown by elevated plasma renin activity (PRA), is implicated in many of the features of metabolic syndrome. The direct renin inhibitor aliskiren may be of benefit in this patient group as aliskiren targets the RAAS at the rate-limiting step. In this double-blind study, 141 patients with hypertension (mean baseline BP 155/93 mm Hg) and metabolic syndrome (modified National Cholesterol Education Program ATP III criteria) were randomized to aliskiren 300 mg or irbesartan 300 mg once daily. Patients treated with aliskiren 300 mg had their mean sitting blood pressure (BP) lowered by 13.8/7.1 mm Hg after 12 weeks, significantly greater (P≤0.001) than the 5.8/2.8 mm Hg reduction observed in patients treated with irbesartan 300 mg. A significantly greater proportion of patients treated with aliskiren achieved BP control to <135/85 mm Hg (29.2 vs 16.7% with irbesartan; P=0.019). Aliskiren treatment led to a 60% decrease in PRA from baseline, whereas irbesartan increased PRA by 99% (both P<0.001). Aliskiren and irbesartan had similar effects on glucose and lipid profiles and on a panel of biomarkers of inflammation and cardiovascular risk. Both aliskiren and irbesartan were well tolerated. Collectively, these results suggest that aliskiren 300 mg may offer treatment benefits compared with irbesartan 300 mg for BP reduction in patients with hypertension and metabolic syndrome.


Assuntos
Amidas/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Compostos de Bifenilo/uso terapêutico , Fumaratos/uso terapêutico , Hipertensão/tratamento farmacológico , Síndrome Metabólica/tratamento farmacológico , Tetrazóis/uso terapêutico , Adulto , Idoso , Glicemia/efeitos dos fármacos , Doenças Cardiovasculares/tratamento farmacológico , Método Duplo-Cego , Feminino , Humanos , Inflamação/sangue , Irbesartana , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Renina/sangue , Sistema Renina-Angiotensina/efeitos dos fármacos , Resultado do Tratamento
13.
Diabet Med ; 27(3): 303-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20536493

RESUMO

AIMS: To assess whether differences exist in the control and intensity of medication treatment of cardiovascular risk factors in secondary prevention patients with Type 2 diabetes, depending on their atherosclerotic disease territory [coronary artery disease (CAD), cerebrovascular disease (CBVD) or peripheral arterial disease (PAD)]. METHODS: Cross-sectional analysis of 17 571 patients with Type 2 diabetes with prevalent atherosclerotic disease. Endpoints included uncontrolled cardiovascular disease (CVD) risk factors [systolic blood pressure (SBP) > or = 140 mmHg, low-density lipoprotein cholesterol > or = 3.4 mmol/l and glycated haemoglobin > or = 8.0%] and high intensity of medication treatment (defined as > or = 2 classes of anti-hypertensive agents, > or = 1 lipid-lowering agent or either insulin or > or = 2 oral glucose-lowering agents) in patients with uncontrolled CVD risk factors. Multiple-adjusted odds ratios were calculated for CAD, CBVD and PAD after adjusting for sex, age, body mass index, current smoking and diabetes duration. RESULTS: Proportions of patients with uncontrolled risk factors were significantly different among disease territories. Decreased odds of having lipids not controlled were observed in patients with CAD, while decreased odds of having systolic blood pressure not controlled were observed in patients with PAD. PAD was associated with the highest odds of hyperglycaemia not being controlled. High-intensity treatment was observed in lipid and blood glucose management but not in hypertension management, independent of disease location. CONCLUSIONS: In subjects with Type 2 diabetes and atherosclerotic disease, control of modifiable CVD risk factors but not intensity of medication treatment is modified by atherosclerotic disease territory. Intensity of medication treatment is different between risk factors.


Assuntos
Anti-Hipertensivos/uso terapêutico , Aterosclerose/complicações , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Disparidades em Assistência à Saúde , Idoso , Aterosclerose/fisiopatologia , Pressão Sanguínea , Doenças Cardiovasculares/fisiopatologia , LDL-Colesterol/sangue , Estudos Transversais , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Hemoglobinas Glicadas/análise , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco
14.
Exp Clin Endocrinol Diabetes ; 118(8): 473-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20198559

RESUMO

Dipeptidyl-peptidase (DPP)-4, which catalizes the degradation of the insulinotropic incretin glucagon-like-peptide (GLP)-1, and the DPP-4 like enzyme attractin are involved in activation of T-lymphocytes and monocytes. Recently, it has been demonstrated, that the risk for certain infections is increased in type 2 diabetic patients under DPP-4 inhibitor treatment. The aim of the present study was to examine the expression of DPP-4 and attractin in circulating blood monocytes of obese and type 2 diabetic subjects. Monocytes were isolated by CD14-antibody based magnetic cell sorting from blood samples of 17 lean controls, 20 obese, non-diabetic subjects and 19 obese patients with type 2 diabetes. FACS analysis was performed to test purity of the cell preparations. Expression was measured by multiplex RT-PCR on RNA-level. DPP-4 and attractin were detectable in human circulating monocytes with attractin being expressed at higher levels compared to DPP-4. Both enzymes were significantly higher expressed in circulating blood monocytes of obese subjects compared to lean controls. In contrast, type 2 diabetes did not significantly affect expression levels. Finally, neither DPP-4 nor attractin expression was altered by sitagliptin or insulin treatment. In conclusion, our data demonstrate, that expressions of DPP-4 and attractin in circulating blood monocytes of human subjects are influenced by metabolic abnormalities with obesity being an important factor.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Dipeptidil Peptidase 4/sangue , Proteínas de Membrana/sangue , Monócitos/enzimologia , Obesidade/sangue , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/enzimologia , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Feminino , Peptídeo 1 Semelhante ao Glucagon/sangue , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Receptores de Lipopolissacarídeos/análise , Masculino , Pessoa de Meia-Idade , Obesidade/enzimologia , Pirazinas/uso terapêutico , Fosfato de Sitagliptina , Triazóis/uso terapêutico
15.
Horm Metab Res ; 42(4): 268-73, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20091460

RESUMO

Low-grade inflammation is important in the development of obesity related pathologies such as insulin resistance and type 2 diabetes, and also cardiovascular disease. Visfatin/PBEF/Nampt and resistin are proinflammatory adipokines secreted from adipocytes, monocytes, and macrophages, and have been linked to atherosclerotic plaque formation, recently. The aim of the present study was to investigate if the expression of these molecules in circulating blood monocytes is altered in obese and/or type 2 diabetic human subjects. Monocytes were isolated by CD14-antibody based magnetic cell sorting from blood samples of 17 lean controls, 20 obese nondiabetic subjects, and 19 obese patients with type 2 diabetes. FACS analysis was performed to test purity of the cell preparations. Expression of the different adipokines was measured by multiplex real-time PCR on RNA-level. Visfatin/PBEF/Nampt was found to be very strongly expressed in monocytes, whereas resistin levels were significantly lower. Furthermore, visfatin/PBEF/Nampt expression was significantly upregulated in obese type 2 diabetic patients, whereas obese nondiabetics exhibited similar levels compared to lean controls, indicating that visfatin/PBEF/Nampt levels are related to type 2 diabetes rather than to obesity. In contrast, resistin expression displayed a different pattern being significantly increased in obese subjects compared to controls but not related to type 2 diabetes. These data suggest a differential role for these two proinflammatory adipokines in linking metabolic diseases to atherosclerosis with visfatin/PBEF/Nampt being more important in patients with type 2 diabetes and resistin in obese but nondiabetic human subjects.


Assuntos
Citocinas/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Monócitos/enzimologia , Nicotinamida Fosforribosiltransferase/sangue , Obesidade/sangue , Obesidade/complicações , Resistina/sangue , Antropometria , Citocinas/genética , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/genética , Feminino , Glucose/farmacologia , Humanos , Inflamação/sangue , Inflamação/complicações , Insulina/farmacologia , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Nicotinamida Fosforribosiltransferase/genética , Obesidade/enzimologia , Obesidade/genética , Resistina/genética
16.
J Mol Endocrinol ; 44(2): 99-113, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19755487

RESUMO

Recent studies have discovered changes in the insulin-/IGF1 signaling affecting glucose metabolism and the molecular pathogenesis of human hepatocellular cancer. Insulin/IGF1 receptor mediates its intracellular effects by recruitment of one out of the four different insulin receptor substrates (IRS). To investigate mechanisms of IRS2 expression, we analyzed transcriptional regulation of IRS2 in human HepG2 cells. We identified a region 688 bp upstream of the translation start codon responsible for approximately 90% of basal human IRS2 promoter activity in HepG2 cells, and confirmed binding of specificity protein 1 (also called Sp1 transcription factor, SP1) and nuclear factor 1 (NFI) in this region. Mutation of both SP1 and NFI binding sites or inhibition of extracellular signal regulated kinase (ERK) suppressed IRS2 promoter activity almost completely, revealing a major role of MAP kinases (MAPK) for IRS2 transcription. Activating this cascade with oxidative stress increased IRS2 promoter activity and endogenous IRS2 expression substantially. IRS2 promoter activity rose even more after additional inhibition of p38MAPK indicating an inhibitory effect of p38MAPK on ERK mediated IRS2 transcription. Activation of the MAPK pathway using interleukin 1, beta (IL1B) increased IRS2 promoter activity similar to oxidative stress. In contrast IL1B decreases and inhibition of the MAPK pathway increases IRS1 promoter activity revealing opposed effects of IL1B and ERK on the expression of different IRS proteins. In conclusion we discovered a specific region (-688 to -611 bp) in the IRS2 promoter essential for basal promoter activity and oxidative stress induced transcription depending on ERK activation and SP1 and NFI binding in human hepatocytes.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas Substratos do Receptor de Insulina/genética , Fatores de Transcrição NFI/metabolismo , Regiões Promotoras Genéticas/genética , Fator de Transcrição Sp1/metabolismo , Estresse Fisiológico/genética , Transcrição Gênica , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Células Hep G2 , Humanos , Interleucina-1beta/farmacologia , Modelos Genéticos , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , PPAR gama/metabolismo , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos
18.
Exp Clin Endocrinol Diabetes ; 117(3): 146-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19053019

RESUMO

Recent studies suggest that the perinatal period is a sensitive part in human development with respect to the pathogenesis of metabolic diseases in adulthood. Neonates, who are either small or large for gestational age (SGA or LGA) have a greater risk of developing obesity and insulin resistance in later life. The term "perinatal priming" is used to describe this phenomenon. Therefore, in the present study we first aimed to investigate if birth weight influences fetal adiponectin and RBP-4 metabolism. Umbilical cord blood was obtained form 40 neonates born on term+/-4 weeks and the adipokine concentrations in the serum were measured. In this analysis adiponectin but not RBP-4 levels showed a positive significant correlation to birth weight. Since maternal preconceptional obesity is associated with an increased birth weight and the risk for LGA neonates, we further aimed to investigate, if the maternal nutritional state influences fetal adiponectin and RBP-4. Therefore umbilical cord blood levels of the adipokines were correlated to maternal preconceptional BMI. In this analysis, neither adiponectin nor RBP-4 levels showed a significant correlation. Taken together, in the present study for the first time we directly compare fetal adiponectin and RBP-4 levels in respect to birth weight and maternal preconceptional BMI. Our data suggest that (1) adiponectin is more likely to have a role in perinatal priming of obesity and insulin resistance than RBP-4 and (2) that birth weight has a greater impact on fetal adipokine serum levels than maternal preconceptional obesity.


Assuntos
Adiponectina/sangue , Peso ao Nascer , Sangue Fetal/química , Feto/metabolismo , Obesidade/fisiopatologia , Complicações na Gravidez/fisiopatologia , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Gravidez , Efeitos Tardios da Exposição Pré-Natal
19.
J Endocrinol Invest ; 31(8): 718-23, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18852533

RESUMO

OBJECTIVE: To assess the efficacy and safety of a novel long-acting im testosterone undecanoate (TU) formulation in comparison with testosterone enanthate (TE). SUBJECTS AND METHODS: An open-label, randomized, prospective clinical trial in 40 hypogonadal men (baseline serum testosterone levels <5 nmol/l), randomly assigned to 250 mg TE/3 weeks (no.=20) or 1000 mg TU im every 6 to 9 weeks for 30 weeks (no.=20). Subsequently, 32/40 men continued the study for another 114 weeks, now receiving TU 1000 mg/12 weeks. RESULTS: TU and TE produced no statistically significant improvements in grip strength over the first 30 weeks, which only occurred after approximately 90 weeks when all subjects received TU. There were no changes in body mass index with TU and TE, neither in the follow-up period when all patients received TU. But ratios of waist to hip circumferences declined in the longer term. Total serum cholesterol, LDL cholesterol, and triglycerides declined over the first 30 weeks, while plasma HDL also declined. Plasma LDL decreased further under long-term TU therapy, while HDL then increased. Hemoglobin and hematocrit values significantly increased over the first 30 weeks in both treatment groups and then no further increase was observed. Levels did not exceed the upper limit of normal. In both treatment groups, serum prostate specific antigen levels rose slightly after 30 weeks, with no further increase over the first 12 months, remaining stable within the normal range. Plasma T before the following TU injection was above the lower limit of reference values. Four injections per year are adequate. CONCLUSIONS: Administration of TU every 12 weeks is at least as safe and efficacious for treatment of hypogonadal men as TE, with a substantially lower frequency of administration. Follow-up over 114 weeks, when all subjects received TU, showed an excellent profile of efficacy and safety.


Assuntos
Hipogonadismo/tratamento farmacológico , Testosterona/análogos & derivados , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Química Farmacêutica , Preparações de Ação Retardada , Força da Mão/fisiologia , Humanos , Injeções Intramusculares , Leptina/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Testosterona/administração & dosagem , Testosterona/efeitos adversos , Relação Cintura-Quadril , Adulto Jovem
20.
J Intern Med ; 264(4): 340-50, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18397244

RESUMO

OBJECTIVES: Patient gender influences the quality of medical care whilst the role of physician gender is not well established. To investigate the influence of physician gender on quality of care in patients with type 2 diabetes. DESIGN AND METHODS: Cross-sectional study in 51 053 outpatients (48.6% male), treated by 3096 office-based physicians (66.3% male; 74.0% general practitioners, 21.8% internists and 4.2% diabetologists). Outcome measures included processes of care, intermediate outcomes and medical management. Quality of care measures were based on current ADA guidelines. Hierarchical regression models were used to avoid case-mix bias and to correct for physician-level clustering. Adjusted odds ratios were calculated controlling for age, gender, disease duration and presence of atherosclerotic disease. RESULTS: The patients of female physicians were more often women, more obese, older and had more often atherosclerotic disease (34% in the total cohort). The patients of female physicians more often reached target values in glycaemic control (HbA1c < 6.5%; OR 1.14; 1.05-1.24, P = 0.002), blood lipoproteins (LDL-C < 100 mg dL(-1); OR 1.16; 1.06-1.27, P = 0.002), and blood pressure (systolic values < 130 mmHg; OR 1.11; 1.02-1.22, P = 0.018). They were more likely to receive antihypertensive drug therapy in general (OR 1.35; 1.24-1.46, P < 0.0001) and angiotensin converting enzyme (ACE) inhibitors in particular (OR 1.17; 1.09-1.25, P < 0.0001). The patients of female physicians less often performed glucose self-monitoring (OR 0.83; 0.76-0.91, P < 0.0001) and less often received oral hypoglycaemic agents (OR 0.88; 0.82-0.95, P = 0.001). CONCLUSIONS: Physician gender influences quality of care in patients with type 2 diabetes. Female physicians provide an overall better quality of care, especially in prognostically important risk management.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Médicos , Padrões de Prática Médica/normas , Garantia da Qualidade dos Cuidados de Saúde , Fatores Sexuais , Idoso , Aterosclerose/complicações , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Medicina de Família e Comunidade/normas , Feminino , Humanos , Masculino , Corpo Clínico Hospitalar , Pessoa de Meia-Idade , Cooperação do Paciente , Relações Médico-Paciente , Médicas , Análise de Regressão , Resultado do Tratamento
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