RESUMEN
AIMS/HYPOTHESIS: Mesenchymal stem cells (MSCs) have been shown to abrogate in vitro the proinflammatory response in type 1 diabetes. The mechanism involves paracrine factors, which may include microvesicles (MVs). We evaluated whether MVs derived from heterologous bone-marrow MSCs exert an immunomodulatory effect on T cell responses against GAD (glutamic acid decarboxylase) antigen in type 1 diabetes. METHODS: MVs were purified from heterologous human MSCs by differential centrifugation. Peripheral blood mononuclear cells (PBMCs) were obtained from patients with type 1 diabetes at disease onset, and responses to GAD65 stimulation were assessed by IFN-γ enzyme-linked immunosorbent spot analysis. Levels of cytokines and prostaglandin E2 (PGE2) were measured in the supernatant fraction, and T helper 17 (Th17) and regulatory T cell analysis was performed. RESULTS: MVs were internalised by PBMCs, as assessed by confocal microscopy and flow cytometry analyses. MVs significantly decreased IFN-γ spots and levels in GAD65-stimulated PBMCs, and significantly increased transforming growth factor-ß (TGF-ß), IL-10, IL-6 and PGE2 levels. Furthermore, MVs decreased the number of Th17 cells and the levels of IL-17, and increased FoxP3(+) regulatory T cells in GAD65-stimulated PBMCs. CONCLUSIONS/INTERPRETATION: These results provide evidence that MSC-derived MVs can inhibit in vitro a proinflammatory response to an islet antigenic stimulus in type 1 diabetes. The action of MVs involves PGE2 and TGF-ß signalling pathways and IL-10 secretion, suggesting a switch to an anti-inflammatory response of T cells.
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Diabetes Mellitus Tipo 1/inmunología , Glutamato Descarboxilasa/inmunología , Células Madre Mesenquimatosas/metabolismo , Linfocitos T/inmunología , Adulto , Citocinas/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Dinoprostona/metabolismo , Femenino , Humanos , Masculino , Linfocitos T/metabolismo , Adulto JovenRESUMEN
MicroRNAs (miRNAs), a class of small non-protein-encoding RNAs, regulate gene expression via suppression of target mRNAs. MiRNAs are present in body fluids in a remarkable stable form as packaged in microvesicles of endocytic origin, named exosomes. In the present study, we have assessed miRNA expression in urinary exosomes from type 1 diabetic patients with and without incipient diabetic nephropathy. Results showed that miR-130a and miR-145 were enriched, while miR-155 and miR-424 reduced in urinary exosomes from patients with microalbuminuria. Similarly, in an animal model of early experimental diabetic nephropathy, urinary exosomal miR-145 levels were increased and this was paralleled by miR-145 overexpression within the glomeruli. Exposure of cultured mesangial cells to high glucose increased miR-145 content in both mesangial cells and mesangial cells-derived exosomes, providing a potential mechanism for diabetes-induced miR-145 overexpression. In conclusion, urinary exosomal miRNA content is altered in type 1 diabetic patients with incipient diabetic nephropathy and miR-145 may represent a novel candidate biomarker/player in the complication.
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Albuminuria/orina , Diabetes Mellitus Tipo 1/orina , Nefropatías Diabéticas/orina , Exosomas/metabolismo , MicroARNs/orina , Animales , Células Cultivadas , Expresión Génica , Glucosa/fisiología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , Persona de Mediana Edad , Regulación hacia ArribaRESUMEN
Diabetic retinopathy is the leading cause of blindness in adults, and oxidative stress has been pathogenically associated with retinal neurodegeneration. Cellular stresses induce expression of heat shock proteins (HSPs) and this results in cytoprotection. Our aim was to assess retinal expression of HSP25 in early experimental diabetes. Mice were rendered diabetic by streptozotocin injection. Ten weeks after diabetes onset retinal HSP25 expression were studied by real-time PCR, immunoblotting and immunohistochemistry (IHC). Expression of nitrotyrosine and Cu/Zn superoxide dismutase (SOD), was assessed by IHC and apoptosis by TUNEL. Retinal HSP25 mRNA and protein expression was significantly increased in diabetic as compared to non-diabetic animals and localised predominantly within the retinal ganglion cells (RGC) layer. This was paralleled overexpression of nitrotyrosine and SOD and enhanced apoptosis. In early experimental diabetes, HSP25 is overexpressed in the RGC layer in parallel with markers of oxidative stress and apoptosis.
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Diabetes Mellitus Experimental/complicaciones , Retinopatía Diabética/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Neoplasias/metabolismo , Retina/metabolismo , Animales , Apoptosis , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Retinopatía Diabética/genética , Retinopatía Diabética/fisiopatología , Femenino , Proteínas de Choque Térmico/genética , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Chaperonas Moleculares , Proteínas de Neoplasias/genética , Estrés Oxidativo , Retina/citología , Células Ganglionares de la Retina/citología , Células Ganglionares de la Retina/metabolismo , Regulación hacia ArribaRESUMEN
Levels of serum heat shock protein 27 (sHsp27) have been studied in numerous cancer types, but their potential relevance in patients with hepatocellular carcinoma (HCC) is undetermined. Our aim was to compare sHsp27 levels in patients with HCC and HCC-free controls. Specifically, we recruited 71 patients with HCC (80 % with early tumour), 80 patients with chronic liver disease (59 with liver cirrhosis and 21 with chronic active hepatitis) and 42 healthy subjects. sHsp27 was measured by immunoenzymatic assay. Results showed that sHsp27 levels were significantly (p < 0.001) higher in patients with HCC than in the other groups, particularly in those with hepatitis C virus (HCV)-related disease. In HCC patients, sHsp27 levels were not associated with prognostic risk factors, such as size/multiplicity of nodules and stage. In logistic regression analysis, performed in patients with liver disease, log-sHsp27 was associated with a significant age-adjusted 2.5-fold increased odds ratio of HCC and with a significant 4.4-fold higher odds ratio of HCC in the subgroup with HCV-related liver disease. In receiver operating characteristic curve analysis, sensitivity and specificity of the best sHsp27 cut-off value (456.5 pg/ml) for differentiating patients with HCC from those with HCC-free chronic liver disease were 70 and 73 %, respectively. In conclusion, sHsp27 levels are enhanced in patients with HCC and may represent a candidate biomarker of HCC.
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Carcinoma Hepatocelular/sangre , Proteínas de Choque Térmico HSP27/sangre , Neoplasias Hepáticas/sangre , Anciano , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/patología , Femenino , Hepatitis C/sangre , Hepatitis C/complicaciones , Hepatitis C/patología , Humanos , Cirrosis Hepática/sangre , Cirrosis Hepática/patología , Hepatopatías/sangre , Hepatopatías/patología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Oportunidad Relativa , Fragmentos de Péptidos/sangre , Pronóstico , Protrombina , Curva ROC , Factores de Riesgo , Índice de Severidad de la Enfermedad , alfa-Fetoproteínas/análisisRESUMEN
OBJECTIVE: Circulating levels of NH(2)-terminal probrain natriuretic peptide (NT-proBNP), a marker of acute heart failure, are associated with increased risk of cardiovascular disease (CVD) in the general population. However, there is little information on the potential role of NT-proBNP as a biomarker of vascular complications in type 1 diabetic patients. We investigated whether serum NT-proBNP levels were associated with micro- and macrovascular disease in type 1 diabetic subjects. RESEARCH DESIGN AND METHODS: A cross-sectional nested case-control study from the EURODIAB Prospective Complications Study of 507 type 1 diabetic patients was performed. Case subjects (n = 345) were defined as those with one or more complications of diabetes; control subjects (n = 162) were those with no evidence of any complication. We measured NT-proBNP levels by a two-site sandwich electrochemiluminescence immunoassay and investigated their associations with complications. RESULTS: Mean NT-proBNP levels were significantly higher in case than in control subjects. In logistic regression analyses, NT-proBNP values >26.46 pg/mL were independently associated with a 2.56-fold increased risk of all complications. Odds ratios of CVD (3.95 [95% CI 1.26-12.35]), nephropathy (4.38 [1.30-14.76]), and distal symmetrical polyneuropathy (4.32 [1.41-13.23]) were significantly increased in patients with NT-proBNP values in the highest quartile (>84.71 pg/mL), independently of renal function and known risk factors. These associations were no longer significant after inclusion of TNF-α into the model. CONCLUSIONS: In this large cohort of type 1 diabetic subjects, we found an association between NT-proBNP and diabetic micro- and macrovascular complications. Our results suggest that the inflammatory cytokine TNF-α may be involved in this association.
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Complicaciones de la Diabetes/metabolismo , Péptido Natriurético Encefálico/metabolismo , Fragmentos de Péptidos/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Adulto , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Inmunoensayo , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVE: Frequent episodes of severe hypoglycemia may increase the risk of cardiovascular disease (CVD) in people with diabetes. Our aim was to study the relationship between severe hypoglycemic episodes and CVD incidence in subjects with type 1 diabetes, and further, to assess if markers of inflammation/endothelial injury were enhanced in individuals who experienced hypoglycemic episodes. RESEARCH DESIGN AND METHODS: The prospective study included 2,181 type 1 diabetic patients from the EURODIAB Prospective Complications Study. At baseline, frequency of self-reported severe hypoglycemia, defined as episodes serious enough to require the help of another person, was assessed based on responses to a patient questionnaire. Both fatal/nonfatal CVD was assessed 7.3 years after baseline examination. At the follow-up visit, data on both severe and nonsevere hypoglycemic episodes in the previous year were collected through a questionnaire and markers of inflammation/stress response/endothelial injury measured by enzyme-linked immunosorbent assays in the 531 subjects of the nested case-control study, including 363 case subjects with one or more complications of diabetes and 168 control subjects with no evidence of any complication. RESULTS: During the follow-up period, 176 patients had incident CVD. Logistic regression analysis showed that severe hypoglycemia at the baseline examination was not associated with incidence of CVD (adjusted odds ratios [95% CI]: one to two episodes, 0.87 [0.55-1.37]; three or more episodes, 1.09 [0.68-1.75]). Furthermore, follow-up serum levels of markers of endothelial damage/inflammation were not cross-sectionally associated with the frequency of hypoglycemic episodes. CONCLUSIONS: Taken together our data do not support the hypothesis that in type 1 diabetes, severe hypoglycemia increases the risk of CVD.
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Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus Tipo 1/complicaciones , Hipoglucemia/complicaciones , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Hipoglucemia/epidemiología , Incidencia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , RiesgoRESUMEN
OBJECTIVES: Compressive ultrasonography (CUS) of the lower limbs is the first choice for identifying deep venous thrombosis (DVT) in patients with symptomatic pulmonary embolism (PE). The aim of this study was to uncover clinical characteristics and CUS findings in patients with proven PE and their correlations with PE extent. METHODS: A total of 524 consecutive cases of proven symptomatic PE diagnosed between January 1996 and December 2006 were reviewed. RESULTS: Mean age was 71.06 ± 14.43 SD years; 244 patients (46.6%) were men. DVT signs or symptoms were present in 30.9% of patients and were associated with the femoral site (P = 0.029). CUS was performed in 383 patients (73.1%) and DVT was found in 75.5%. In 94.1% of patients DVT was proximal (popliteal and/or femoral), which would have been then identified by simplified CUS. CUS was performed significantly more often in presence of signs or symptoms of DVT (P < 0.001), less often in presence of medical illnesses (P = 0.040), age ≥75 years (P = 0.001) and death in hospital (P < 0.001). Signs or symptoms of DVT were predictors of positive CUS (P < 0.001), presence of medical illnesses (P = 0.020), central venous catheter (P = 0.035), death in hospital (P = 0.032) were predictors of negative CUS findings. Neither clinical findings nor CUS were associated with PE extent. CONCLUSIONS: In patients with proven symptomatic PE, signs or symptoms of DVT are present only in 1/3 of cases and are significantly more frequent when DVT is extended to the femoral vein. Simplified CUS of the lower limbs has a high sensitivity in finding proximal DVT. CUS is not able to predict PE extent.
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Vena Femoral/diagnóstico por imagen , Extremidad Inferior/diagnóstico por imagen , Vena Poplítea/diagnóstico por imagen , Embolia Pulmonar/complicaciones , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/epidemiología , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Extremidad Inferior/patología , Masculino , Persona de Mediana Edad , Flebografía , Valor Predictivo de las Pruebas , Prevalencia , Sensibilidad y Especificidad , Tomografía Computarizada Espiral , Ultrasonografía , Trombosis de la Vena/complicacionesRESUMEN
CONTEXT: Mesenchymal stem cells (MSCs) exert an immunosuppressive effect on the immune system. However, studies on the immunomodulatory potential of MSCs in type 1 diabetes are lacking. OBJECTIVE: We aimed to evaluate whether human MSCs may inhibit in vitro pancreatic islet antigen-specific T cell activation in type 1 diabetes. DESIGN: Human MSCs were isolated and characterized. Peripheral blood mononuclear cells (PBMCs) were obtained from nine type 1 diabetic patients at disease onset and 13 healthy control subjects. IFN-gamma, IL-10, and IL-4 enzyme-linked immunospot responses of lymphocytes incubated with glutamic acid decarboxylase 65 (GAD65) were investigated in PBMC cultures and PBMC/MSC cocultures. Levels of prostaglandin E2 (PGE2), IFN-gamma, IL-4, and IL-10 in supernatants were measured by ELISA. PGE2 inhibition experiments with NS-398 and indomethacin were also performed. RESULTS: Five diabetic patients were identified with a positive PBMC IFN-gamma response to GAD65 and negative IL-10 and IL-4 response. PBMC/MSC cocultures resulted in a significant decrease in the number of spots and in detection of IL-4-secreting cells. PGE2 inhibitors abrogated the immune-suppressive effect, indicating an involvement of PGE2 production, and the constitutive production of PGE2 by MSCs was enhanced in PBMC/MSC coculture. Moreover, in GAD-responder patients, GAD-stimulated PBMC/MSC cocultures significantly decreased secretion of IFN-gamma and IL-10 and increased secretion of IL-4. CONCLUSIONS: These results provide evidence that human MSCs abrogate in vitro a proinflammatory T helper type 1 response to an islet antigenic stimulus in type 1 diabetes. MSCs induce IL-4-producing cells, suggesting a possible switch to an antiinflammatory T helper type 2 signaling of T cells.
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Diabetes Mellitus Tipo 1/inmunología , Glutamato Descarboxilasa/farmacología , Inmunidad Celular/inmunología , Células Madre Mesenquimatosas/inmunología , Linfocitos T/inmunología , Células Cultivadas , Técnicas de Cocultivo , Diabetes Mellitus Tipo 1/metabolismo , Dinoprostona/inmunología , Dinoprostona/metabolismo , Ensayo de Inmunoadsorción Enzimática , Glutamato Descarboxilasa/inmunología , Humanos , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-10/inmunología , Interleucina-10/metabolismo , Interleucina-4/inmunología , Interleucina-4/metabolismo , Islotes Pancreáticos/inmunología , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/inmunología , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Células Madre Mesenquimatosas/citología , Estadísticas no Paramétricas , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismoRESUMEN
Diabetic nephropathy is the leading cause of end-stage renal failure in the Western World and accounts for significant morbidity and mortality in patients with diabetes. Although hyperglycaemia and hypertension are established key determinants in the development of the complication, recent studies suggest that a low-grade inflammatory response may also play a role. Monocyte Chemoattractant Protein 1 (MCP-1), a potent chemokine produced by renal cells, has emerged as a very important player in this process. Specifically, it has been shown that MCP-1 is overexpressed in the kidneys from diabetic animals. Furthermore, there is amelioration of both functional and structural abnormalities in MCP-1- knockout mice in the setting of concomitant diabetes. Over recent years the cellular mechanisms linking MCP-1 to kidney injury have been increasingly delineated and, in particular, it has become evident that MCP-1 contributes to the kidney damage not only by inducing mononuclear cell recruitment, but also by direct activation of resident renal cells. The present review focuses on the most significant advances in understanding the role of MCP-1 in diabetic kidney disease and future potential therapeutic implications.
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Quimiocina CCL2/metabolismo , Nefropatías Diabéticas/tratamiento farmacológico , Riñón/metabolismo , Animales , Quimiocinas/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/metabolismo , Humanos , Hiperglucemia/complicaciones , Hipertensión/complicaciones , Riñón/fisiopatología , Fallo Renal Crónico/complicaciones , Ratones , Ratones Noqueados , Ratones Transgénicos , Terapia Molecular Dirigida , Receptores CCR2RESUMEN
OBJECTIVE: Cannabinoid receptor 1 (CB1) is localized in the central nervous system and in peripheral tissues involved in energy metabolism control. However, CB1 receptors are also expressed at low level within the glomeruli, and the aim of this study was to investigate their potential relevance in the pathogenesis of proteinuria in experimental type 1 diabetes. RESEARCH DESIGN AND METHODS: Streptozotocin-induced diabetic mice were treated with N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,3-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251), a selective CB1-receptor antagonist, at the dosage of 1 mg x kg(-1) x day(-1) via intraperitoneal injection for 14 weeks. Urinary albumin excretion was measured by enzyme-linked immunosorbent assay. CB1 receptor expression was studied by immunohistochemistry, immunoblotting, and real-time PCR. Expression of nephrin, podocin, synaptopodin, and zonula occludens-1 (ZO-1) was assessed by immunofluorescence and real-time PCR. Fibronectin, transforming growth factor-beta1 (TGF-beta1), and connective tissue growth factor (CTGF) mRNA levels were quantitated by real-time PCR. RESULTS: In diabetic mice, the CB1 receptor was overexpressed within the glomeruli, predominantly by glomerular podocytes. Blockade of the CB1 receptor did not affect body weight, blood glucose, and blood pressure levels in either diabetic or control mice. Albuminuria was increased in diabetic mice compared with control animals and was significantly ameliorated by treatment with AM251. Furthermore, CB1 blockade completely prevented diabetes-induced downregulation of nephrin, podocin, and ZO-1. By contrast overexpression of fibronectin, TGF-beta1, and CTGF in renal cortex of diabetic mice was unaltered by AM251 administration. CONCLUSIONS: In experimental type 1 diabetes, the CB1 receptor is overexpressed by glomerular podocytes, and blockade of the CB1 receptor ameliorates albuminuria possibly via prevention of nephrin, podocin, and ZO-1 loss.
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Albuminuria/prevención & control , Nefropatías Diabéticas/prevención & control , Receptor Cannabinoide CB1/antagonistas & inhibidores , Animales , Factor de Crecimiento del Tejido Conjuntivo/genética , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/fisiopatología , Fibronectinas/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Fosfoproteínas/genética , Piperidinas/uso terapéutico , Reacción en Cadena de la Polimerasa/métodos , Pirazoles/uso terapéutico , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Crecimiento Transformador beta1/genética , Proteína de la Zonula Occludens-1RESUMEN
Association of type 1 diabetes and cytomegalovirus (CMV) is suspected and CMV infections have also been linked to increased risk of new onset post-transplantation diabetes. We monitored response to islet autoantigens, pancreatic endocrine function, and CMV infections in one type 1 diabetic patient receiving pancreas allograft. Time course analyses of levels of islet autoantibodies (Abs), IFN-gamma ELISPOT response, analysis of T cell function, levels of C peptide together with CMV pp65 antigenaemia and viraemia and graft biopsy histopathology were performed in comparison with a cohort of diabetic recipients. Evidence of autoimmune activation to GAD and IA2, modification of CD4(+) CD25hi T cells, loss of pancreatic function, concomitantly with multiple CMV infections and allograft rejection with peri-insulitis is provided. The parallel between metabolic outcome, initiation and progression of autoreactivity to islet autoantigens and early CMV infections after transplantation, suggests that persistent CMV infections may be relevant to the pathogenesis of type 1 diabetes.
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Autoantígenos , Autoinmunidad , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/inmunología , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/cirugía , Islotes Pancreáticos/inmunología , Trasplante de Páncreas/inmunología , Adulto , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/fisiopatología , Femenino , Humanos , Inmunidad Celular , Inmunidad Humoral , Trasplante de Páncreas/efectos adversos , Trasplante de Páncreas/patología , Trasplante de Páncreas/fisiología , RecurrenciaRESUMEN
Increased glomerular permeability to proteins is a characteristic feature of diabetic nephropathy (DN). The slit diaphragm is the major restriction site to protein filtration, and the loss of nephrin, a key component of the slit diaphragm, has been demonstrated in both human and experimental DN. Both systemic and glomerular hypertension are believed to be important in the pathogenesis of DN. Human immortalized podocytes were subjected to repeated stretch-relaxation cycles by mechanical deformation with the use of a stress unit (10% elongation, 60 cycles/min) in the presence or absence of candesartan (1 microM), PD-123319 (1 microM), and rosiglitazone (0.1 microM). Nephrin mRNA and protein expression were assessed using quantitative real-time PCR, immunoblotting, and immunofluorescence, and the protein expression of AT(1) receptor and angiotensin II secretion were evaluated. Exposure to stretch induced a significant approximately 50% decrease in both nephrin mRNA and protein expression. This effect was mediated by an angiotensin II-AT(1) mechanism. Indeed, podocyte stretching induced both angiotensin II secretion and AT(1) receptor overexpression, podocyte exposure to angiotensin II reduced nephrin protein expression, and both the AT-1 receptor antagonist candesartan and a specific anti-angiotensin II antibody completely abolished stretch-induced nephrin downregulation. Similar to candesartan, the peroxisome proliferator-activated receptor (PPAR)-gamma agonist, rosiglitazone, also inhibited stretch-induced nephrin downregulation, suggesting interference with stretch-induced activation of the angiotensin II-AT(1) receptor system. Accordingly, rosiglitazone did not alter stretch-induced angiotensin II secretion, but it prevented AT(1) upregulation in response to stretch. These results suggest a role for hemodynamic stress in loss of nephrin expression and allude to a role of PPAR-gamma agonists in the prevention of this loss.
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Proteínas de la Membrana/metabolismo , Podocitos/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo , Estrés Mecánico , Angiotensina II/farmacología , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Apoptosis/fisiología , Proliferación Celular , Células Cultivadas , Nefropatías Diabéticas/fisiopatología , Regulación hacia Abajo/efectos de los fármacos , Humanos , Proteínas de la Membrana/genética , PPAR gamma/agonistas , Podocitos/citología , Podocitos/fisiología , ARN Mensajero/metabolismo , Rosiglitazona , Tiazolidinedionas/farmacología , Regulación hacia Arriba/efectos de los fármacosAsunto(s)
Trastornos de Deglución/etiología , Insuficiencia de la Válvula Mitral/complicaciones , Anciano , Trastornos de Deglución/diagnóstico por imagen , Dilatación Patológica/complicaciones , Dilatación Patológica/diagnóstico por imagen , Atrios Cardíacos/diagnóstico por imagen , Humanos , Masculino , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: Monocyte chemoattractant protein-1 (MCP-1), a chemokine binding to the CC chemokine receptor 2 (CCR2) and promoting monocyte infiltration, has been implicated in the pathogenesis of diabetic nephropathy. To assess the potential relevance of the MCP-1/CCR2 system in the pathogenesis of diabetic proteinuria, we studied in vitro if MCP-1 binding to the CCR2 receptor modulates nephrin expression in cultured podocytes. Moreover, we investigated in vivo if glomerular CCR2 expression is altered in kidney biopsies from patients with diabetic nephropathy and whether lack of MCP-1 affects proteinuria and expression of nephrin in experimental diabetes. RESEARCH DESIGN AND METHODS: Expression of nephrin was assessed in human podocytes exposed to rh-MCP-1 by immunofluorescence and real-time PCR. Glomerular CCR2 expression was studied in 10 kidney sections from patients with overt nephropathy and eight control subjects by immunohistochemistry. Both wild-type and MCP-1 knockout mice were made diabetic with streptozotocin. Ten weeks after the onset of diabetes, albuminuria and expression of nephrin, synaptopodin, and zonula occludens-1 were examined by immunofluorescence and immunoblotting. RESULTS: In human podocytes, MCP-1 binding to the CCR2 receptor induced a significant reduction in nephrin both mRNA and protein expression via a Rho-dependent mechanism. The MCP-1 receptor, CCR2, was overexpressed in the glomerular podocytes of patients with overt nephropathy. In experimental diabetes, MCP-1 was overexpressed within the glomeruli and the absence of MCP-1 reduced both albuminuria and downregulation of nephrin and synaptopodin. CONCLUSIONS: These findings suggest that the MCP-1/CCR2 system may be relevant in the pathogenesis of proteinuria in diabetes.
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Quimiocina CCL2/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Nefropatías Diabéticas/fisiopatología , Proteínas de la Membrana/genética , Podocitos/fisiología , Animales , Biopsia , Células Cultivadas , Quimiocina CCL2/genética , Quimiocina CCL2/farmacología , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Regulación hacia Abajo/fisiología , Humanos , Técnicas In Vitro , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de Microfilamentos/metabolismo , Fosfoproteínas/metabolismo , Podocitos/citología , Proteinuria/metabolismo , Proteinuria/patología , Proteinuria/fisiopatología , ARN Mensajero/metabolismo , Proteínas Recombinantes/farmacología , Proteína de la Zonula Occludens-1 , Quinasas Asociadas a rho/metabolismoRESUMEN
OBJECTIVE: To assess whether serum anti-heat shock protein 27 (HSP27) antibody levels are associated with micro- and macrovascular complications of type 1 diabetes. RESEARCH DESIGN AND METHODS: Anti-HSP27 IgG antibody levels were measured in 531 type 1 diabetic subjects recruited as part of the cross-sectional analysis of the EURODIAB Prospective Complications Study. Case subjects (n = 363) were defined as individuals with one or more diabetes complications and control subjects (n = 168) as individuals with no evidence of any diabetes complication. RESULTS: Anti-HSP27 levels were comparable in case and control subjects (19.6 arbitrary units/ml [11.3-32.7] vs. 20.4 arbitrary units/ml [11.7-35.3], geometric mean [interquartile range]), and there was no correlation between HSP27 and anti-HSP27 levels (r = 0.01, P = 0.81). In logistic regression analysis, anti-HSP27 was not associated with the presence of complications, even after adjustment for main risk factors. CONCLUSIONS: Anti-HSP27 antibody levels are not a marker of vascular complications in type 1 diabetes.
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Anticuerpos/sangre , Complicaciones de la Diabetes/inmunología , Proteínas de Choque Térmico HSP27/inmunología , Inmunoglobulina G/sangre , Complicaciones de la Diabetes/sangre , Complicaciones de la Diabetes/epidemiología , Angiopatías Diabéticas/complicaciones , Retinopatía Diabética/complicaciones , Ensayo de Inmunoadsorción Enzimática , Humanos , Valores de Referencia , Análisis de Regresión , Factores de RiesgoRESUMEN
OBJECTIVE: To determine to what extent plasma C-reactive protein (CRP) values influence 5-year all-cause and cardiovascular mortality in type 2 diabetic individuals, independently of albumin excretion rate (AER) and other cardiovascular risk factors, and its incremental usefulness for predicting individual risk of mortality. RESEARCH DESIGN AND METHODS: Measurements of CRP were performed in 2,381 of 3,249 (73.3%) subjects as part of the population-based Casale Monferrato Study. Its association with 5-year all-cause and cardiovascular mortality was assessed with multivariate Cox proportional hazards modeling. The C statistic and measures of calibration and global fit were also assessed. RESULTS: Results are based on 496 deaths in 11.717 person-years of observations (median follow-up 5.4 years). With respect to subjects with CRP < or =3 mg/l, those with higher values had an adjusted hazard ratio (HR) of 1.51 (95% CI 1.18-1.92) for all-cause mortality and 1.44 (0.99-2.08) for cardiovascular mortality. In normoalbuminuric subjects, respective HRs of CRP were 1.56 (1.13-2.15) and 1.65 (1.00-2.74), AER being neither a modifier nor a confounder of CRP association. In analysis limited to diabetic subjects without cardiovascular disease (CVD), adjusted HRs were 1.67 (1.24-2.24) for all-cause mortality and 1.36 (0.83-2.24) for cardiovascular mortality. The improvement in individual risk assessment was marginal when measured with various statistical measures of model discrimination, calibration, and global fit. CONCLUSIONS: CRP measurement is independently associated with short-term mortality risk in type 2 diabetic individuals, even in normoalbuminuric subjects and in those without a previous diagnosis of CVD. Its clinical usefulness in individual assessment of 5-year risk of mortality, however, is limited.
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Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Diabetes Mellitus Tipo 2/mortalidad , Angiopatías Diabéticas/mortalidad , Anciano , Anciano de 80 o más Años , Aterosclerosis/sangre , Presión Sanguínea , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/fisiopatología , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Inflamación/sangre , Italia/epidemiología , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Factores de Riesgo , Análisis de Supervivencia , SobrevivientesRESUMEN
Heat shock protein (HSP) HSP27, HSP60, HSP70, and HSP90 are induced by cellular stresses and play a key role in cytoprotection. Both hyperglycemia and glomerular hypertension are crucial determinants in the pathogenesis of diabetic nephropathy and impose cellular stresses on renal target cells. We studied both the expression and the phosphorylation state of HSP27, HSP60, HSP70, and HSP90 in vivo in rats made diabetic with streptozotocin and in vitro in mesangial cells and podocytes exposed to either high glucose or mechanical stretch. Diabetic and control animals were studied 4, 12, and 24 wk after the onset of diabetes. Immunohistochemical analysis revealed an overexpression of HSP25, HSP60, and HSP72 in the diabetic outer medulla, whereas no differences were seen in the glomeruli. Similarly, exposure neither to high glucose nor to stretch altered HSP expression in mesangial cells and podocytes. By contrast, the phosphorylated form of HSP27 was enhanced in the glomerular podocytes of diabetic animals, and in vitro exposure of podocytes to stretch induced HSP27 phosphorylation via a P38-dependent mechanism. In conclusion, diabetes and diabetes-related insults differentially modulate HSP27, HSP60, and HSP70 expression/phosphorylation in the glomeruli and in the medulla, and this may affect the ability of renal cells to mount an effective cytoprotective response.
Asunto(s)
Nefropatías Diabéticas/genética , Proteínas de Choque Térmico/genética , Animales , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/fisiopatología , Nefropatías Diabéticas/patología , Proteínas de Choque Térmico/metabolismo , Glomérulos Renales/patología , Glomérulos Renales/fisiopatología , Médula Renal/patología , Médula Renal/fisiopatología , Masculino , Fosforilación , Ratas , Ratas Sprague-Dawley , Valores de ReferenciaRESUMEN
OBJECTIVE: Heat shock protein 27 (HSP27) is a member of the small heat shock protein family of proteins. HSP27 expression is enhanced in target tissues of diabetic microvascular complications, and changes in circulating serum HSP27 levels (sHSP27) have been reported in patients with macrovascular disease. We investigated whether sHSP27 levels were associated with micro- and macrovascular complications in type 1 diabetic patients. RESEARCH DESIGN AND METHODS: A cross-sectional, nested, case-control study from the EURODIAB Prospective Complications Study of 531 type 1 diabetic patients was performed. Case subjects (n = 363) were defined as those with one or more complications of diabetes; control subjects (n = 168) were defined as those with no evidence of any complication. We measured sHSP27 levels and investigated their associations with diabetes complications. RESULTS: Mean sHSP27 levels were significantly higher in case subjects with distal symmetrical polyneuropathy (DSP) than in control subjects, even after adjustment for age and albumin excretion rate (AER) (785.9 vs. 574.7 pg/ml, P = 0.03). In logistic regression analysis, sHSP27 levels in the upper quartile were associated with a twofold increased odds ratio (OR) of DSP, independently of conventional risk factors, markers of inflammation, and AER (OR 2.41 [95% CI 1.11-5.24]). CONCLUSIONS: In this large cohort of type 1 diabetic subjects, we found an independent association between sHSP27 and DSP. This suggests that sHSP27 levels may be a novel marker for diabetic neuropathy.
Asunto(s)
Biomarcadores/sangre , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/complicaciones , Nefropatías Diabéticas/sangre , Neuropatías Diabéticas/sangre , Proteínas de Choque Térmico/sangre , Proteínas de Neoplasias/sangre , Adulto , Presión Sanguínea , Estudios de Casos y Controles , Estudios Transversales , Angiopatías Diabéticas/sangre , Femenino , Proteínas de Choque Térmico HSP27 , Humanos , Masculino , Persona de Mediana Edad , Chaperonas MolecularesRESUMEN
INTRODUCTION: Proximalisation of colon carcinoma has been reported over the course of the last 60 years. Changes in site distribution are receiving increasing attention on account of their implications for screening programmes. OBJECTIVE: A retrospective observational study to determine whether the site distribution of colorectal carcinoma in Italy has varied in the last years and whether changes have been influenced by age and sex. METHODS: Findings of colonscopies conducted at Turin University from 1992 to 2001 were examined. Inclusion criteria were: outpatients, screening, presence of anaemia or gastrointestinal bleeding, weight loss, constipation or changes in evacuation frequency. Exclusion criteria were: uncompleted, surgical endoscopies or conducted for positive flexible sigmoidoscopy, with doubtful findings. Carcinomas and benign polyps were diagnosed histologically. Age, sex, date of examination, nature and location of lesions were recorded. Lesions were classed as carcinoma, and polyps <1 and >/=1 cm. Data were grouped into different year periods and compared with the chi square test. We compared 1992-1993 vs. 2000-2001 and 1992-1996 vs. 1997-2001. RESULTS: Of the 8,132 colonoscopies performed, 7,342 were included in the study. Proximal carcinomas moved from 12.2% in 1992-1993 to 14.9% in 2000-2001 (P = 0.57), proximal polyps rose from 16.6% to 22.1% (P < 0.0001). Furthermore proximal carcinomas moved from 16.5% in 1992-1996 to 14.4% in 1997-2001 (P = 0.48); proximal polyps rose from 18.4% to 27.8% (P < 0.005). In the period 1996-2001 there was higher female prevalence (P = 0.0011) and older age (P = 0.0191). DISCUSSION: We can suppose that proximalisation of carcinoma has not yet appeared in Italy.