Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Studies from several laboratories suggest that oxidized LDL may play an important role in atherogenesis. Our group previously showed that treatment of aortic endothelial cells with low levels of MM-LDL caused increased expression of MCP-1, M-CSF, tissue factor, and a monocyte-binding protein. In these studies MM-LDL was produced by storage of native LDL. We now show that cocultures of endothelial and smooth muscle cells can also produce MM-LDL from native LDL. This production of MM-LDL by cells is prevented by preincubating the LDL with probucol or vitamin E. However, addition of antioxidants to MM-LDL did not block its action. In past studies we also showed that endothelial cells exhibit differential sensitivity to the effects of MM-LDL. We report herein that in resistant cells there is no elevation of catalase, glutathione peroxidase, or copper-zinc-dependent SOD. However, manganese-dependent SOD is elevated in resistant cells. Ways in which MM-LDL production may be elevated in poorly controlled diabetics subjects are discussed.
Diabetes 1992 Oct
PMID:Minimally modified lipoproteins in diabetes. 152 40

Diabetes mellitus is complicated with vascular disorders such as atherosclerosis (macroangiopathy) and retinopathy (microangiopathy). In macroangiopathy, AGE plays an important role in atherogesis through NF-kappa B activation, that induces VCAM-1 and MCP-1. Diabetic retinopathy is based on the microangiopathy characteristic of angiogenesis. VEGF is a key substance in the angiogenesis in the retina. VEGF is produced from retinal cells exposed to AGE, adenosine, bFGF. VEGF elictes angiogenesis and increased vascular permeability (retinal edema). I consider that AGE is the most important substance in diabetic vascular disorder. Therefore, I expect a new application for diabetic angiopathy to suppress the effect of AGE.
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PMID:[Vascular endothelial cell dysfunction in diabetes mellitus]. 1019 36

The vascular endothelium influences not only the three classically interacting components of hemostasis: the vessel, the blood platelets and the clotting and fibrinolytic systems of plasma, but also the natural sequelae: inflammation and tissue repair. Two principal modes of endothelial behaviour may be differentiated, best defined as an anti- and a prothrombotic state. Under physiological conditions endothelium mediates vascular dilatation (formation of NO, PGI2, adenosine, hyperpolarizing factor), prevents platelet adhesion and activation (production of adenosine, NO and PGI2, removal of ADP), blocks thrombin formation (tissue factor pathway inhibitor, activation of protein C via thrombomodulin, activation of antithrombin III) and mitigates fibrin deposition (t- and scuplasminogen activator production). Adhesion and transmigration of inflammatory leukocytes are attenuated, e.g. by NO and IL-10, and oxygen radicals are efficiently scavenged (urate, NO, glutathione, SOD). When the endothelium is physically disrupted or functionally perturbed by postischemic reperfusion, acute and chronic inflammation, atherosclerosis, diabetes and chronic arterial hypertension, then completely opposing actions pertain. This prothrombotic, proinflammatory state is characterised by vaso-constriction, platelet and leukocyte activation and adhesion (externalization, expression and upregulation of von Willebrand factor, platelet activating factor, P-selectin, ICAM-1, IL-8, MCP-1, TNF alpha, etc.), promotion of thrombin formation, coagulation and fibrin deposition at the vascular wall (expression of tissue factor, PAI-1, phosphatidyl serine, etc.) and, in platelet-leukocyte coaggregates, additional inflammatory interactions via attachment of platelet CD40-ligand to endothelial, monocyte and B-cell CD40. Since thrombin formation and inflammatory stimulation set the stage for later tissue repair, complete abolition of such endothelial responses cannot be the goal of clinical interventions aimed at limiting procoagulatory, prothrombotic actions of a dysfunctional vascular endothelium.
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PMID:Endothelial function and hemostasis. 1079 71

Nonenzymatic glycation is increased in diabetes. The role of advanced glycation end products has been implicated in many of the complications of diabetes, whereas the effects of early-glycation Amadori-modified proteins on vascular cells alone are poorly defined. In the present study, we show that glycated serum albumin (GSA) induces a parallel activation of the redox-responsive transcription factors (nuclear factor kappaB) and AP-1 and increases activity of mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase (ERK), and p38 MAPK in vascular smooth muscle cells (VSMCs). GSA increased expression of early response genes, c-fos and c-jun, and inflammatory genes, monocyte chemoattractant peptide (MCP-1), and interleukin (IL)-6. These effects were comparable to bacterial lipopolysaccharide, tumor necrosis factor-alphaa, (TNF-alphaa), IL-1alphab, angiotensin II, epidermal growth factor, and the phorbol ester PMA. One of signaling pathways by which GSA activates VSMCs appears to be via nuclear factor kappaB activation, leading to induction of MCP-1 and IL-6 gene expression, comparable to the effects of lipopolysaccharide, TNF-alphaa, and IL-1alphab. Another signaling cascade by which GSA activates VSMCs is the ERK-->c-Fos-->AP-1 pathway, which may lead to stimulation of cell proliferation and migration. These effects are comparable to the effects of angiotensin II, epidermal growth factor, and PMA. Incubation of VSMCs with the antioxidant N-acetylcysteine suppressed GSA-elicited mRNA induction of MCP-1 and IL-6. Inhibition of p38 MAPK but not ERK caused attenuation of MCP-1 and IL-6 mRNA induction. Finally, GSA caused a significant stimulation of VSMC growth and migration. These findings suggest that GSA may play a role in diabetic atherogenesis by activating VSMCs, leading to induction of inflammatory mediators in the vessel wall, as well as proliferation and migration of VSMCs.
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PMID:Vascular smooth muscle cell activation by glycated albumin (Amadori adducts). 1179 73

Chronic lipid exposure is implicated in beta-cell dysfunction in type 2 diabetes. We therefore used oligonucleotide arrays to define global alterations in gene expression in MIN6 cells after 48-h pretreatment with oleate or palmitate. Altogether, 126 genes were altered > or =1.9-fold by palmitate, 62 by oleate, and 46 by both lipids. Importantly, nine of the palmitate-regulated genes are known to be correspondingly changed in models of type 2 diabetes. A tendency toward beta-cell de-differentiation was also apparent with palmitate: pyruvate carboxylase and mitochondrial glycerol 3-phosphate dehydrogenase were downregulated, whereas lactate dehydrogenase and fructose 1,6-bisphosphatases were induced. Increases in the latter (also seen with oleate), along with glucosamine-phosphate N-acetyl transferase, imply upregulation of the hexosamine biosynthesis pathway in palmitate-treated cells. However, palmitate also increased expression of calcyclin and 25-kDa synaptosomal-associated protein (SNAP25), which control distal secretory processes. Consistent with these findings, secretory responses to noncarbohydrate stimuli, especially palmitate itself, were upregulated in palmitate-treated cells (much less so with oleate). Indeed, glucose-stimulated secretion was slightly sensitized by chronic palmitate exposure but inhibited by oleate treatment, whereas both lipids enhanced basal secretion. Oleate and palmitate also induced expression of chemokines (MCP-1 and GRO1 oncogene) and genes of the acute phase response (serum amyloid A3). Increases in transcriptional modulators such as ATF3, CCAAT/enhancer binding protein-beta (C/EBPbeta), C/EBPdelta, and c-fos were also seen. The results highlight links between regulated gene expression and phenotypic alterations in palmitate versus oleate-pretreated beta-cells.
Diabetes 2002 Apr
PMID:Expression profiling of palmitate- and oleate-regulated genes provides novel insights into the effects of chronic lipid exposure on pancreatic beta-cell function. 2194

The coexistence of hypercholesterolaemia and diabetes dramatically and synergistically increases the risk of microvascular and macrovascular complications in patients. A single unifying mechanism of increased production of reactive oxygen species (ROS) by angiotensin II (Ang II) may serve as a causal link between hyperglycaemia and hypercholesterolaemia and many of the major pathways responsible for atherogenic and diabetic disorders. Several lines of evidence suggest a crucial role for Ang II-mediated oxidative stress in the pathogenesis of hyperglycaemia- and hypercholesterolemia-associated endothelial dysfunction. Endothelial dysfunction in these scenarios may be due to impaired nitric oxide (NO) synthesis and/or inactivation of endothelium-derived NO by ROS. That Ang II plays an important role in the development of atherosclerosis and glomerulosclerosis is supported by numerous studies indicating that angiotensin receptor blockers (ARBs) retard the progression of these diseases in both experimental animal models and humans. Evidence indicates that Ang II contributes to atherogenesis at both transcriptional and translational levels by upregulating adhesion molecule mRNA and protein synthesis. The recent demonstration of Ang II AT(2) receptors in the adult kidney and their potential to oppose the vasoconstrictive, antinatriuretic, and profibrotic properties of AT(1) receptors suggests that the balance of intrarenal AT(1) and AT(2) receptors may be important in determining the cellular responses to Ang II in diabetic nephropathy. Results of these studies suggest that hypercholesterolaemia and hyperglycaemia can induce a pro-inflammatory response within coronary arteries and the kidney glomerulus. This response involves production of well described macrophage chemotactic and adhesion molecules, which results in macrophage recruitment and the development of acute and chronic injury. Glomerular macrophage recruitment in experimental diabetes occurs via Ang II-stimulated monocyte chemoattractant protein (MCP)-1 expression, suggesting that the renin-angiotensin system is an important regulator of local MCP-1 expression, and strongly implicating macrophage recruitment and activation in the pathogenesis of early diabetic glomerular injury. Diabetes-associated vascular complications may also involve an activation of the nuclear factor (NF)-kappaB by hyperglycaemia. NF-kappaB activation is related to AT(1) receptor-mediated pathways, and is believed to be dependent on activation of the Rho proteins belonging to the superfamily of low molecular weight guanosine triphosphatases (GTPases) that regulate intracellular signalling. Preincubation of vascular smooth muscle cells with insulin doubled NF-kappaB transactivation stimulated by Ang II and hyperglycaemia, suggesting a potential mechanism for crosstalk between the renin-angiotensin system and hyperglycaemia. Taken together, these data suggest that activation of the renin-angiotensin system is a mechanism for the initiation and progression of inflammatory cell infiltration found in early changes common to both hypercholesterolaemia and hyperglycaemia. While the base of information regarding ARBs in high-risk patients with diabetes and hypercholesterolemia is lacking, preclinical and pilot trial data suggest that the ARBs are reno- and vasculoprotective in these patients. Therapeutic blockade of Ang II AT(1) receptors in diabetic and hypercholesterolaemic humans by ARBs, with concomitant elevation in plasma and tissue Ang II levels, may provide vascular and renal protection not only by reducing AT(1) receptor-mediated pro-oxidative effects, but also by unopposed AT(2) receptor stimulation.
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PMID:[Pathophysiological and clinical implications of AT(1) and AT(2) angiotensin II receptors in metabolic disorders: hypercholesterolaemia and diabetes]. 1203 87

Peroxisome proliferator-activated receptor-gamma (PPARgamma) ligands are widely used in patients with insulin resistance and diabetes. Because coronary artery disease is a major complication for such patients, it is important to determine the effects of PPARgamma activation on arteriosclerosis. Long-term inhibition of endothelial NO synthesis by administration of N(omega)-nitro-L-arginine methyl ester (L-NAME) to rats induces coronary vascular inflammation (monocyte infiltration, monocyte chemoattractant protein-1 [MCP-1] expression) and subsequent arteriosclerosis. We examined the effects of pioglitazone (a PPARgamma ligand) in this rat model to determine whether PPARgamma activation with pioglitazone inhibits arteriosclerosis by its indirect effects on metabolic conditions or by direct effects on the cells participating to the pathogenesis of arteriosclerosis. We found that pioglitazone did not affect metabolic states, systolic blood pressure, or serum NO levels, but did prevent the L-NAME-induced coronary inflammation and arteriosclerosis. Pioglitazone did not reduce local expression of MCP-1 but markedly attenuated increased expression of the MCP-1 receptor C-C chemokine receptor 2 (CCR2) in lesional and circulating monocytes. PPARgamma activation with pioglitazone prevented coronary arteriosclerosis, possibly by its antiinflammatory effects (downregulation of CCR2 in circulating monocytes). Inhibition of the CCR2-mediated inflammation may represent novel antiinflammatory actions of pioglitazone beyond improvement of metabolic state.
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PMID:Antiinflammatory and antiarteriosclerotic effects of pioglitazone. 1241 63

Accumulating evidence suggests that C-reactive protein (CRP), at concentrations known to predict diverse vascular insults, directly promotes endothelial cell activation, uncovering a proatherosclerotic and proinflammatory phenotype. In the present study, we hypothesized that (a). hyperglycemia would serve to exaggerate the proatherogenic effects of CRP and (b). the PPARgamma agonist, rosiglitazone would attenuate this effect. Human saphenous vein endothelial cells were studied under the following conditions (n= 10 per group): control, human recombinant CRP (25 microg/ml, 24 h), hyperglycemia (25 mM, 24 h) and hyperglycemia + CRP. In each case, the effects of co-incubation with rosiglitazone (1 microM) were evaluated. Nitric oxide and endothelin-1 release from endothelial cells was quantified, in addition to the expression of adhesion molecules and monocyte chemoattractant chemokine (MCP-1). Incubation of endothelial cells with CRP increased endothelin-1 production, and upregulated adhesion molecule and MCP-1 expression. These proatherogenic effects of CRP were potentiated in the presence of hyperglycemia. CRP also decreased endothelial nitric oxide release, and this effect remained unchanged by hyperglycemia. Importantly, the PPARgamma agonist, rosiglitazone, attenuated the proatherogenic effects of CRP under both basal and hyperglycemic conditions. The direct proatherogenic actions of CRP are exaggerated in the hyperglycemic milieu, and attenuated by rosiglitazone. Elevated CRP levels in patients with diabetes may serve to uncover a severe proatherogenic phenotype.
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PMID:Hyperglycemia potentiates the proatherogenic effects of C-reactive protein: reversal with rosiglitazone. 1268 21

Islet transplantation is now established as an optional treatment for type I diabetes. However, rates of insulin independence in islet transplant recipients are still low. Although the major source of allograft is derived from brain-dead patient, the nonphysiologic state of brain death (BD) deteriorates organs such as liver and kidney. To determine the effects of BD on islets, a rodent model of BD has been used. Histologically, islets of BD rats showed decreased permeability and impaired integrity of the cell membranes. Flow cytometric analysis showed that CD11b/c-positive cells within islets were slightly increased in BD. This result suggests that BD induces macrophage infiltration into the islets. Moreover, RT-PCR revealed significant augmentation of macrophages-associated inflammatory molecules (IL-1beta, IL-6, TNF-alpha, and MCP-1) in islets from a BD donor. Inducible nitric oxide synthase (iNOS) was weakly expressed, although not reaching statistical significance compared with control. Our results indicate that islets from a BD donor are immunologically activated and have a potential risk factor for early graft loss and a poor long-term function of grafts in clinical setting of islet transplantation. Immunomodulation, to eliminate intraislet immunocytes and/or activated macro phage-associated molecules, might be necessary for the better outcome after islet graft from BD donors.
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PMID:Activation of macrophage-associated molecules after brain death in islets. 1269 61

At onset of type 1 diabetes, the islet autoantibody status of patients has been reported to predict progression of the disease. We therefore tested the hypothesis that the systemic immunoregulatory balance, as defined by levels of circulating cytokines and chemokines, is associated with islet autoantibody status. In 50 patients with recent-onset type 1 diabetes, antibodies to GAD and insulinoma-associated antigen 2 (IA-2) were analyzed by radioimmunoassay; cytoplasmic islet cell antibodies were determined by indirect immunofluorescence. Cytokine and chemokine concentrations were measured by rigidly evaluated double antibody enzyme-linked immunosorbent assay. Of four classically defined Th1/Th2 cytokines (gamma-interferon, interleukin [IL]-5, IL-10, IL-13), none showed an association with multiple autoantibody positivity. Of six mediators mainly produced by innate immunity cells, three were associated with multiple autoantibody status (IL-18 increased, MIF and MCP-1 decreased) and three were unaffected (IL-12, MIP-1beta, IP-10). GAD and/or IA-2 antibody titers negatively correlated with systemic concentrations of MIF, MIP-1beta, and IL-12. Combining the data of several cytokine and chemokine levels made it possible to predict islet antibody positivity in individual patients with 85% sensitivity and 94% specificity. These data suggest a close association of islet antibody status with systemic immunoregulation in type 1 diabetes.
Diabetes 2003 May
PMID:An association of autoantibody status and serum cytokine levels in type 1 diabetes. 1271 43


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