Fibronectin glycation increases IGF-I induced proliferation of human aortic smooth muscle cells

The advanced glycation end products, namely AGEs, contribute to long-termed complications of diabetes mellitus, including macroangiopathy, where smooth muscle cells (SMC) proliferation stimulated by platelet-derived growth factor (PDGF) isoforms and insulin-like growth factor-I (IGF-I) plays an important role. The objective of the present study was to investigate the effect of an AGE-modified extracellular matrix protein on IGF-I induced SMC proliferation and on the IGF-I-IGF binding protein 4 (IGFBP-4) axis under basal conditions and after stimulation with PDGF-BB. IGF-I resulted in significantly higher thymidine incorporation in SMC seeded on AGE-modified fibronectin (AGE-FN) in comparison to cells seeded on fibronectin (FN). This augmented proliferation could not be accounted for by increased expression of IGF-IR, by decreased secretion of IGFBP-4, a binding protein that inhibits IGF-I mitogenic effects or by increased IGF-IR autophosphorylation. PDGF-BB did not modulate IGF-IR and IGFBP-4 mRNA expression in any of the substrata, however, this growth factor elicited opposite effects on the IGFBP-4 content in the conditioned media, increasing it in cells plated on FN and diminishing it in cells plated on AGE-FN. These findings suggest that one mechanism by which AGE-modified proteins is involved in the pathogenesis of diabetes-associated atherosclerosis might be by increasing SMC susceptibility to IGF-I mitogenic effects.FAPESP, Sao Paulo, Brazil [91/3617-8]FAPESP (Sao Paulo, Brazil

Could pre-diabetes be considered a clinical condition? opinions from an endocrinologist and a cardiologist

The prevalence of pre-diabetes is increasing worldwide and may start 7 to 10 years before the clinical diagnosis of diabetes. In this stage the presence and accumulation of risk factors is common and already implies an increase in cardiovascular risk. Likewise, the onset of cardiovascular diseases (CVD), mainly coronary artery disease (CAD), peripheral vascular disease and cerebrovascular disease can also take place, all of which account for high rates of morbidity and mortality worldwide. Considering pre-diabetes as a clinical entity, non-pharmacological and pharmacological treatments are indicated with drugs which have shown clinical benefits related to reduction in morbidity and mortality. However, there is still need for new long-term studies to assess the real benefits of several new therapeutical approaches, as well as its cost-effectiveness

Apoptosis rate and transcriptional response of pancreatic islets exposed to the PPAR gamma agonist Pioglitazone

To explore the molecular pathways underlying thiazolidinediones effects on pancreatic islets in conditions mimicking normo- and hyperglycemia, apoptosis rate and transcriptional response to Pioglitazone at both physiological and supraphysiological glucose concentrations were evaluated. Adult rat islets were cultured at physiological (5.6 mM) and supraphysiological (23 mM) glucose concentrations in presence of 10 μM Pioglitazone or vehicle. RNA expression profiling was evaluated with the PancChip 13k cDNA microarray after 24-h, and expression results for some selected genes were validated by qRT-PCR. The effects of Pioglitazone were investigated regarding apoptosis rate after 24-, 48- and 72-h. At 5.6 mM glucose, 101 genes were modulated by Pioglitazone, while 1,235 genes were affected at 23 mM glucose. Gene networks related to lipid metabolism were identified as altered by Pioglitazone at both glucose concentrations. At 23 mM glucose, cell cycle and cell death pathways were significantly regulated as well. At 5.6 mM glucose, Pioglitazone elicited a transient reduction in islets apoptosis rate while at 23 mM, Bcl2 expression was reduced and apoptosis rate was increased by Pioglitazone. Our data demonstrate that the effect of Pioglitazone on gene expression profile and apoptosis rate depends on the glucose concentration. The modulation of genes related to cell death and the increased apoptosis rate observed at supraphysiological glucose concentration raise concerns about Pioglitazone’s direct effects in conditions of hyperglycemia and reinforce the necessity of additional studies designed to evaluate TZDs effects on the preservation of β-cell function in situations where glucotoxicity might be more relevant than lipotoxicity.This work was supported by grants from NIDDK (UO1 DK 56947; P30 DK 19525) and from FAPESP (04/018165, 04/014670 and 04/107974). The authors are grateful to Takeda Chemicals Industries (Japan) for supplying pioglitazone hydrochloride pure substance.This work was supported by grants from NIDDK (UO1 DK 56947; P30 DK 19525) and from FAPESP (04/01816-5, 04/01467-0 and 04/10797-4). The authors are grateful to Takeda Chemicals Industries (Japan) for supplying pioglitazone hydrochloride pure substance

Baixos níveis de glicemia e outras complicações durante suplementação de hormônio do crescimento na sepse

O perfil glicêmico esperado em pacientes pós-operatórios sépticos recebendo nutrição enteral de elevado teor calórico é de valores sanguíneos no limite superior do normal ou mesmo hiperglicemia moderada.A adição de hormônio do crescimento (GH) como agente anabólico deveria reforçar ainda mais esta tendência.Num paciente com câncer submetido a gastrectomia parcial e linfadenectomia, que se complicou no pós operatório com abscesso subfrênico e sepse prolongada, administrou-se conjuntamente dieta de sonda (38,3 kcal/kg/dia) e GH (0,17 UI/kg/dia).Antes da introdução de GH as taxas glicêmicas situavam-se nos limites inferiores do normal, e esta tendência persistiu durante a maior parte do período terapêutico.Duas complicações adicionais, nominalmente parada cardíaca e edema periférico, foram documentadas nesta mesma etapa.Conclui-se que a sepse é o mais provável mecanismo de redução da glicemia neste caso, e que o emprego de dieta enteral e de GH não conseguiu prevenir tal efeito.É questionável se a parada cardíaca foi devida ao suplemento hormonal, mas o edema periférico é um secundarismo bem conhecido deste agente em estudos clínicos.Blood glucose levels in the high normal range or even moderate hyperglycemia is the expected profile in septic postoperative patients receiving high-calorie enteral alimentation. The addition of growth hormone as an anabolic agent should additionally reinforce this tendency. In a cancer patient undergoing partial gastrectomy with lymphadenectomy and suffering from postoperative subphrenic abscess and prolonged sepsis, tube feeding (38.3 kcal/kg/day) and growth hormone (0.17 IU/kg/day) were simultaneously administered for 25 days. Blood glucose levels were in the lower limits of the normal range before growth hormone introduction, and continued with a similar tendency during most of the therapeutic period. Two additional complications, namely heart arrest and peripheral edema, were documented during the same period. It is concluded that sepsis was the most likely mechanism for low glucose values, and that high-calorie enteral diet and growth hormone supplementation did not prevent that result. It is uncertain whether heart arrest was due to the drug, but its association with peripheral edema is well documented in clinical series

PTTG expression in different experimental and human prolactinomas in relation to dopaminergic control of lactotropes

Background: Pituitary tumor transforming gene (pttg) is a novel oncogene that is expressed at higher level in most of the tumors analyzed to date compared to normal tissues. Nevertheless, its expression in prolactinomas and its relation with the pituitary dopamine receptor 2 (D2R) are not well defined. We sought to determine the pituitary level of pttg in three different experimental models of prolactinomas with altered dopaminergic control of the pituitary: the dopaminergic D2R knockout female mouse, the estrogen-treated rat, and the senescent female rat. These three models shared the characteristics of increased pituitary weight, hyperprolactinemia, lactotrope hyperplasia and reduced or absent dopaminergic action at the pituitary level. We also studied samples from human macroprolactinomas, which were characterized as responsive or resistant to dopamine agonist therapy. Results: When compared to female wild-type mice, pituitaries from female D2R knockout mice had decreased PTTG concentration, while no difference in pttg mRNA level was found. In senescent rats no difference in pituitary PTTG protein expression was found when compared to young rats. But, in young female rats treated with a synthetic estrogen (Diethylstylbestrol, 20 mg) PTTG protein expression was enhanced (P = 0.029). Therefore, in the three experimental models of prolactinomas, pituitary size was increased and there was hyperprolactinemia, but PTTG levels followed different patterns. Patients with macroprolactinomas were divided in those in which dopaminergic therapy normalized or failed to normalize prolactin levels (responsive and resistant, respectively). When pituitary pttg mRNA level was analyzed in these macroprolactinomas, no differences were found. We next analyzed estrogen action at the pituitary by measuring pituitary estrogen receptor α levels. The D2R knockout female mice have low estrogen levels and in accordance, pituitary estrogen receptors were increased (P = 0.047). On the other hand, in senescent rats estrogen levels were slightly though not significantly higher, and estrogen receptors were similar between groups. The estrogen-treated rats had high pharmacological levels of the synthetic estrogen, and estrogen receptors were markedly lower than in controls (P < 0.0001). Finally, in patients with dopamine resistant or responsive prolactinomas no significant differences in estrogen receptor α levels were found. Therefore, pituitary PTTG was increased only if estrogen action was increased, which correlated with a decrease in pituitary estrogen receptor level. Conclusion: We conclude that PTTG does not correlate with prolactin levels or tumor size in animal models of prolactinoma, and its pituitary content is not related to a decrease in dopaminergic control of the lactotrope, but may be influenced by estrogen action at the pituitary level. Therefore it is increased only in prolactinomas generated by estrogen treatment, and not in prolactinomas arising from deficient dopamine control, or in dopamine resistant compared with dopamine responsive human prolactinomas. These results are important in the search for reliable prognostic indicators for patients with pituitary adenomas which will make tumor-specific therapy possible, and help to elucidate the poorly understood phenomenon of pituitary tumorigenesis.Facultad de Ciencias Médica

Estimating cardiovascular risk in patients with type 2 diabetes: a national multicenter study in Brazil

According to Brazilian National Data Survey diabetes is the fifth cause for hospitalization and is one of the ten major causes of mortality in this country.Aimsto stratify the estimated cardiovascular risk (eCVR) in a population of type 2 diabetics (T2DM) according to the Framingham prediction equations as well as to determine the association between eCVR with metabolic and clinical control of the disease.MethodsFrom 2000 to 2001 a cross-sectional multicenter study was conducted in 13 public out-patients diabetes/endocrinology clinics from 8 Brazilian cities. the 10-year risk of developing coronary heart disease (CHD) was estimated by the prediction equations described by Wilson et al (Circulation 1998). LDL equations were preferably used; when patients missed LDL data we used total cholesterol equations instead.ResultsData from 1382 patients (59.0% female) were analyzed. Median and inter-quartile range (IQ) of age and duration of diabetes were 57.4 (51-65) and 8.8 (3-13) years, respectively without differences according to the gender. Forty-two percent of these patients were overweight and 35.4% were obese (the prevalence of higher BMI and obesity in this T2DM group was significantly higher in women than in men; p 20%) in 738 (53.4%), intermediate in 202 (14.6%) and low in 442 (32%) patients. Men [25.1(15.4-37.3)] showed a higher eCVR than women [18.8 (12.4-27.9) p < 0.001]. the most common risk factor was high LDL-cholesterol (80.8%), most frequently found in women than in men (p = 0.01). the median of risk factors present was three (2-4) without gender differences. Overall we observed that 60 (4.3%) of our patients had none, 154(11.1%) one, 310 (22.4%) two, 385 (27.9%) three, 300 (21.7%) four, 149 (10.5%) five and six, (2%) six risk factors. A higher eCVR was noted in overweight or obese patients (p = 0.01 for both groups). No association was found between eCVR with age or a specific type of diabetes treatment. A correlation was found between eCVR and duration of diabetes (p < 0.001), BMI (p < 0.001), creatinine (p < 0.001) and triglycerides levels (p < 0.001) but it was not found with HbA1c, fasting blood glucose and postprandial glucose. A higher eCVR was observed in patients with retinopathy (p < 0.001) and a tendency in patients with microalbuminuria (p = 0.06). Conclusion: our study showed that in this group of Brazilian T2DM the eCVR was correlated with the lipid profile and it was higher in patients with microvascular chronic complications. No correlation was found with glycemic control parameters. These data could explain the failure of intensive glycemic control programs aiming to reduce cardiovascular events observed in some studies.Univ Estado Rio de Janeiro, Diabet Unit, Rio de Janeiro, BrazilUniv São Paulo Scholl Med, Hosp Clin, Lab Clin & Expt Gatroenterol LIM07, São Paulo, BrazilUniv Fed Maranhao, Div Endocrinol, Sao Luis, BrazilUniv Estadual Campinas, Div Endocrinol, Campinas, BrazilCtr Estudos Diabet & Endocrinol Estado Bahia CEDE, Salvador, BA, BrazilUniv Fed Parana, Div Endocrinol, BR-80060000 Curitiba, Parana, BrazilHosp Agamenon Magalhaes, Div Endocrinol, Recife, PE, BrazilPosto Assistencia Med Jaguribe, Joao Pessoa, Paraiba, BrazilSanta Casa Porto Alegre, Div Endocrinol, Porto Alegre, RS, BrazilInst Assistencia & Previdencia Servidor Estado Ba, Div Endocrinol, Salvador, BA, BrazilSanta Casa Belo Horizonte, Diabet Unit, Belo Horizonte, MG, BrazilHosp Geral Goiania, Div Endocrinol, Goiania, Go, BrazilSecretaria Municipal Saude Brasilia, Brasilia, DF, BrazilUniversidade Federal de São Paulo, Div Endocrinol, São Paulo, BrazilUniversidade Federal de São Paulo, Div Endocrinol, São Paulo, BrazilWeb of Scienc

Nationwide multicenter study on the prevalence of overweight and obesity in type 2 diabetes mellitus in the Brazilian population

AIM: To evaluate the prevalence of overweight and obesity in type 2 diabetic (DM2) outpatients from different regions of Brazil. PATIENTS AND METHODS: We studied 2,519 randomly selected patients, from 11 hospitals, 2 endocrine and one general public care clinics from 10 cities. Overweight was defined as body-mass index (BMI) > 25 and obesity as BMI > 30 kg/m². Glycemic control (GC) was evaluated by GC index (GCI= patient's HbA1 or HbA1c/upper limit of normal for the method x 100). RESULTS: 39% of the population studied was male, the mean age was 58.8 ± 11.6 y, the duration from clinical diagnosis of DM2 was 9.0 ± 7.3y, and BMI was 28.3 ± 5.2 kg/m². No measurements of BMI were recorded from 265 patients (10.5%). Patients from the Northeast presented lower BMI as compared with those from the Midwest, Southeast and South areas, respectively (26.4 ± 4.7 vs. 27.9 ± 4.8 vs. 29.2 ± 5.1 vs. 29.4 ± 5.4 kg/m²; p 25 e obesidade um IMC > 30 kg/m². O controle glicêmico (CG) foi avaliado pelo índice de CG [ICG= HbA1 e ou HbA1c do paciente/limite superior de normalidade do método x 100]. RESULTADOS: Os pacientes tinham idade de 58,8 ± 11,6 anos, tempo de diagnóstico clínico de DM de 9,0 ± 7,3 anos, IMC de 28,3 ± 5,2 kg/m², e 39% eram do sexo masculino. Do total da amostra, 265 pacientes (10,5%) não apresentavam avaliação do IMC. Os pacientes da região Nordeste apresentaram menor IMC em comparação com os das regiões Centro-Oeste, Sudeste e Sul, respectivamente (26,4 ± 4,7 vs. 27,9 ± 4,8 vs. 29,2 ± 5,1 vs. 29,4 ± 5,4 kg/m²; p< 0,001). Houve maior prevalência de obesidade na região Sudeste e Sul em comparação à região Nordeste (p< 0,001) e nos pacientes do sexo feminino, respectivamente (69 vs. 31%; p< 0,001). Os pacientes com peso normal apresentaram menor ICG. Aqueles em tratamento com associação de duas ou mais drogas orais e associação de insulina + droga oral apresentaram maior IMC do que aqueles em tratamento com dieta, hipoglicemiante oral e insulina; p< 0,001. O IMC não diferiu entre os pacientes assistidos ou não por especialistas. CONCLUSÕES: Da população estudada, 75% não estava na faixa de peso ideal, sendo que um terço tinha obesidade. Nossos dados indicam que o sobrepeso e a obesidade já atingem um percentual de pacientes com DM2 no Brasil semelhante ao relatado em estudos europeus, mas ainda menor do que o observado nos EUA. A prevalência de obesidade nos pacientes diabéticos foi três vezes maior do que a observada na população brasileira em geral de acordo com os dados do IBGE.UERJUSPUNIFESP-EPMUNICAMPUNIFEUniversidade Federal do MaranhãoCEDEBVA Serviço de Endocrinologia e DiabetesHospital Agamenon Magalhães Serviços de EndocrinologiaSanta Casa Serviços de EndocrinologiaIAPSEB Serviços de EndocrinologiaHospital Geral Serviços de EndocrinologiaPAM Jaguaribe Serviços de EndocrinologiaSanta Casa Serviço de DiabetesSecretaria Municipal de SaúdeUNIFESP, EPMSciEL

Prevalence of celiac disease among blood donors in São Paulo: the most populated city in Brazil

OBJECTIVE: Celiac disease is a permanent enteropathy caused by the ingestion of gluten, which leads to an immunemediated inflammation of the small intestine mucosa. The prevalence of celiac disease varies among different nations and ethnic backgrounds, and its diversity is determined by genetic and environmental factors. São Paulo city is one of the largest cities in the world, with a vast population and an important history of internal migratory flow from other Brazilian regions, as well as immigration from other, primarily European, countries, resulting in significant miscegenation. The aim of the present study was to estimate the prevalence of adults with undiagnosed celiac disease among blood donors of São Paulo by collecting information on the ancestry of the population studied. METHODS: The prevalence of celiac disease was assessed by screening for positive IgA transglutaminase and IgA endomysium antibodies in 4,000 donors (volunteers) in the Fundação Pró-Sangue Blood Center of São Paulo, São Paulo, Brazil. The antibody-positive subjects were asked to undergo a small bowel biopsy. RESULTS: Of the 4,000 subjects, twenty-four had positive tests, although both antibody tests were not always concordant. For example, ten subjects were positive for IgA tissue transglutaminase only. In twenty-one positive patients, duodenal biopsies were performed, and the diagnosis of celiac disease was confirmed in fourteen patients (Marsh criteria modified by Oberhuber). In this group, 67% claimed to have European ancestry, mainly from Italy, Portugal and Spain. CONCLUSION: The prevalence of celiac disease is at least 1:286 among supposedly healthy blood bank volunteers in São Paulo, Brazil

Differential expression of genes encoding proteins of the HGF/MET system in insulinomas

Abstract\ud \ud Background\ud Insulinomas are the most common functional pancreatic neuroendocrine tumors, whereas histopathological features do not predict their biological behaviour. In an attempt to better understand the molecular processes involved in the tumorigenesis of islet beta cells, the present study evaluated the expression of genes belonging to the hepatocyte growth factor and its receptor (HGF/MET) system, namely, MET, HGF; HGFAC and ST14 (encode HGF activator and matriptase, respectively, two serine proteases that catalyze conversion of pro-HGF to active HGF); and SPINT1 and SPINT2 (encode serine peptidase inhibitors Kunitz type 1 and type 2, respectively, two inhibitors of HGF activator and of matriptase).\ud \ud \ud Methods\ud Quantitative real-time reverse transcriptase polymerase chain reaction was employed to assess RNA expression of the target genes in 24 sporadic insulinomas: 15 grade 1 (G1), six grade 2 (G2) and three hepatic metastases. Somatic mutations of MET gene were searched by direct sequencing of exons 2, 10, 14, 16, 17 and 19.\ud \ud \ud Results\ud Overexpression of MET was observed in the three hepatic metastases concomitantly with upregulation of the genes encoding HGF and matriptase and downregulation of SPINT1. A positive correlation was observed between MET RNA expression and Ki-67 proliferation index while a negative correlation was detected between SPINT1 expression and the mitotic index. No somatic mutations were found in MET gene.\ud \ud \ud Conclusion\ud The final effect of the increased expression of HGF, its activator (matriptase) and its specific receptor (MET) together with a decreased expression of one potent inhibitor of matriptase (SPINT1) is probably a contribution to tumoral progression and metastatization in insulinomas