Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0011854 (type 1 diabetes)
 20,749 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Microalbuminuria (MA) is associated with microangiopathy (renal and retinal lesions) in insulin-dependent diabetic (IDDM) patients. In contrast MA does not reflect microvascular damage in a substantial number of non-insulin-dependent diabetic (NIDDM) patients. MA predicts cardiovascular disease in NIDDM patients with increased von Willebrand factor (vWF) plasma levels which are hypothesized to reflect endothelial dysfunction. However, it is not known whether MA is consequent to generalised endothelial dysfunction or to renal injury. Thus, this study evaluated vWF plasma levels in relation to renal and retinal structural abnormalities in NIDDM patients with MA. Kidney biopsies, fundoscopy and measures of vWF plasma levels were performed in 32 NIDDM patients with MA. These patients were allocated to two renal structural categories: A) Without renal structural abnormalities (C I, n = 10): normal or near-normal renal structure, and B) With renal structural abnormalities (n = 22), further divided into: C II (n = 12) with typical diabetic nephropathology, predominantly glomerulopathy, and C III (n = 10) with atypical patterns of renal injury (more advanced tubulo-interstitial and arteriolar than glomerular changes). vWF plasma levels were significantly higher in category B (C II: 195+/-49% and C III: 161+/-46%) than in category A (C I: 119+/-42%), (chi-square, p < 0.05). Diabetic retinopathy was also related to vWF plasma levels (ANOVA, p < 0.05). These data suggest that there are two types of MA in NIDDM: one associated with increased vWF levels, established renal injury and frequently retinopathy, and the other characterized by normal vWF levels, normal renal structure and absent or mild diabetic retinopathy. We propose that vWF plasma levels in NIDDM patients with MA may help to identify patients with important renal structural changes, increased retinopathy risk and, perhaps, generalised endothelial dysfunction. Whether vWF plasma levels predict end-stage renal disease and cardiovascular events deserves longitudinal studies.
 ...
PMID:Heterogeneous nature of microalbuminuria in NIDDM: studies of endothelial function and renal structure. 949 59

Recent developments in cell biology have identified new areas of direct relevance to the pathogenesis of Type 1 (insulin-dependent) diabetes mellitus and its complications. Endothelial damage is well recognized in diabetes--endothelial cell markers von Willebrand factor, soluble E-selectin, and soluble thrombomodulin are providing further evidence of the relationship between activation and damage to the vasculature and clinical disease in this condition. Cell surface bound adhesion molecules may also have a role in the development of atherosclerosis in patients with diabetes but the importance of the soluble forms of these molecules, such as intercellular adhesion molecule-1, is unclear. Evidence of platelet dysfunction has long been acknowledged in diabetes and new data are discussed. It is likely that a greater appreciation of the intimate interactions between endothelial integrity, adhesion molecules and platelets in Type 1 diabetes mellitus will provide a greater understanding of the risk of cardiovascular disease and stroke in patients with this disorder.
 ...
PMID:Endothelial integrity, soluble adhesion molecules and platelet markers in type 1 diabetes mellitus. 1022 99

It is unknown whether and to what extent changes in various endothelial functions and adrenergic responsiveness are related to the development of microvascular complications in type 1 diabetes. Therefore, endothelium-dependent and endothelium-independent vasodilatation, endothelium-dependent hemostatic factors, and one and two adrenergic vasoconstrictor responses were determined in type 1 patients with and without microvascular complications. A total of 34 patients with type 1 diabetes were studied under euglycemic conditions on two occasions (11 without microangiopathy, 10 with proliferative and preproliferative retinopathy previously treated by laser coagulation, 13 with microalbuminuria, and 12 healthy volunteers also were studied). Forearm vascular responses to brachial artery infusions of N(G)-monomethyl-L-arginine (L-NMMA), sodium nitroprusside, acetylcholine (ACh), clonidine, and phenylephrine were determined. The ACh infusions were repeated during coinfusion of L-arginine. Furthermore, plasminogen activator inhibitor type 1 (PAI-1) activity, tissue plasminogen activator antigen levels, von Willebrand factor antigen levels, tissue factor pathway inhibitor (TFPI) activity, and endothelin-1 levels were measured. No differences in endothelium-dependent or endothelium-independent vasodilatation or adrenergic constriction were observed between the diabetic patients and the healthy volunteers. In comparison to the first ACh infusion, the maximal response to repeated ACh during L-arginine administration was reduced in the diabetic patients, except in the patients with proliferative and preproliferative retinopathy previously treated by laser coagulation. In these patients, the combined infusion of L-arginine and ACh resulted in an enhanced response. TFPI activity was elevated, and PAI-1 activity was reduced in the type 1 diabetic patients. Furthermore, PAI-1 activity was positively correlated with urinary albumin excretion (r = 0.48, P < 0.01) and inversely correlated with the vasodilatory response to the highest ACh dose (r = -0.37, P < 0.05). The response to the highest ACh and L-NMMA dose were positively correlated with mean arterial blood pressure (r = 0.32, P < 0.01; r = 0.41, P < 0.01, respectively). Forearm endothelium-dependent and endothelium-independent vasodilatation and adrenergic responsiveness were unaltered in type 1 diabetic patients with and without microvascular complications. Relative to healthy control subjects, endothelium-dependent vasodilatation was depressed during a repeated ACh challenge (with L-arginine coinfusion) in the diabetic patients without complications or with microalbuminuria. In contrast, this vasodilatation was enhanced in the patients with retinopathy. Elevation of TFPI was the most consistent marker of endothelial damage of all the endothelial markers measured.
 ...
PMID:Endothelium-dependent vasodilatation, plasma markers of endothelial function, and adrenergic vasoconstrictor responses in type 1 diabetes under near-normoglycemic conditions. 1034 20

In diabetic nephropathy, heparan sulfate glycosaminoglycan side chains are reduced in glomerular basement membranes proportionally to the degree of proteinuria. Recently, it was demonstrated that additional therapy with danaparoid sodium, a mixture of sulfated glycosaminoglycans with mainly heparan sulfate, lowered proteinuria in type 1 diabetes patients with diabetic nephropathy. A randomized placebo-controlled parallel study was performed with 750 anti-Xa units of danaparoid sodium once daily in type 2 diabetes patients with severe proteinuria. The aim of the study was to evaluate the possible effects of danaparoid sodium on proteinuria, endothelial dysfunction, and hard exudates in the retina and to determine the safety/tolerability of this drug. Twenty-two patients completed the study, and one patient had to stop prematurely after 6 wk of danaparoid sodium treatment because of urticaria at the injection sites. Apart from a small decrease of hemoglobin and minor skin hematomas at the injection site in five patients in the danaparoid sodium group, no other safety parameters showed any clinically or statistically significant difference between and within groups. The relative change in time of both the urinary albumin and protein excretion rate corrected for creatinine did not differ between both treatment arms (P = 0.2 and 0.49, respectively). No retinal complications or changes of hard exudates occurred. von Willebrand factor was elevated in both groups, but was not influenced by either treatment modality. Contrary to the beneficial effects that occurred in type 1 diabetes patients with diabetic nephropathy, treatment for 8 wk with 750 anti-Xa units of danaparoid sodium gave no reduction of proteinuria, hard exudates, and von Willebrand factor.
 ...
PMID:Effect of danaparoid sodium on proteinuria, von Willebrand factor, and hard exudates in patients with diabetes mellitus type 2. 1036 73

Patients with diabetes mellitus have a variety of platelet and coagulation system dysfunctions. At least theoretically, these can contribute to microvascular complications. Intensive glycemic control has been demonstrated to decrease microvascular complications in type 1 diabetics. We studied 16 patients with type 1 diabetes mellitus (11 men and five women; mean age, 39 years) with albuminuria greater than 0.1 g/d and/or proteinuria greater than 0.3 g/d and a creatinine clearance rate higher than 30 mL/min. They received a regimen including three to four injections of insulin per day with or without a weekly infusion of intravenous insulin, and were evaluated for 6 months. We compared the plasma level of von Willebrand factor, platelet aggregation responses to adenosine diphosphate (ADP), epinephrine, and collagen, and platelet adhesion at the beginning of the study and at follow-up intervals. Glycemic control improved significantly. There were no significant differences in the platelet aggregation responses to ADP (1.59 +/- 0.34 v 1.88 +/- 0.23 mmol/L, P = .3; normal, 4.6 +/- 0.2), epinephrine (0.50 +/- 0.20 v 1.11 +/- 0.31 mmol/L, P = .06; normal, 7.6 +/- 1.5), or collagen (92.4 +/- 6.61 v 82.60 +/- 3.78 seconds, P = .6; normal, 79.1 +/- 3.1) or in platelet adhesion (126.31 +/- 16.95 v 195.08 +/- 30.2 platelets, P = .34; normal, 68.6 +/- 1.4). Baseline von Willebrand factor increased, but not significantly (166.38% +/- 10.6% v 142.72% +/- 14.73%, P = .21; normal, 102.0% +/- 6.0%). In type 1 diabetic patients with established microvascular complications of nephropathy, a statistically significant improvement in glycemic control did not improve the in vitro platelet function abnormalities. Improved glycemic control delays the progression of microvascular disease through mechanisms not measured by tests of platelet function.
 ...
PMID:Improved glycemic control and platelet function abnormalities in diabetic patients with microvascular disease. 1064 69

The major cause of morbidity and mortality in patients with type 1 diabetes mellitus is vascular disease and the death rate in this group of patients can be up to six times that of the general population. Elevated levels of blood glucose can cause endothelial cell damage, and markers of endothelial damage such as von Willebrand factor (vWF) and thrombomodulin (TM) have been reported to increase in adult diabetic patients. Growth factors are strongly linked to smooth muscle cell proliferation that contributes significantly to the vascular occlusive process and it has been shown that vascular endothelial cell growth factor (VEGF) stimulates release of vWF from endothelial cells. Vascular endothelial cell growth factor levels have been shown to be increased in vitreous fluid from the eyes of diabetic patients with proliferative retinopathy compared to those without. In this study we have shown that plasma levels of both TM and VEGF were significantly increased in juvenile diabetic patients with no clinical evidence of vascular disease compared to normal age and sex-matched control subjects. Median TM levels were 45.5 ng/mL (I.Q.R. 34 to 56 ng/mL) and 61 ng/mL (I.Q.R. 41 to 72 ng/mL) in the control group and in the diabetic patients respectively (p = .0005) and median levels of VEGF were 19.6 pg/mL (I.Q.R. 15.9 to 28.1 pg/mL) in the control group and 37.1 pg/mL (I.Q.R. 22.1 to 50.3 pg/mL) in the diabetic patients (p = .027 Mann-Whitney U test). This suggests that microvascular disease begins in childhood and can be detected using laboratory tests before any clinical changes are apparent.
 ...
PMID:Elevated plasma vascular endothelial cell growth factor and thrombomodulin in juvenile diabetic patients. 1072 78

Cardiovascular disease and the development of coronary artery disease play a pivotal role in increasing mortality in patients with type 1 diabetes. The aim of our study was to evaluate the effects of pancreas transplantation on atherosclerotic risk factors, endothelial-dependent dilation (EDD), and progression of intima media thickness (IMT) in patients with uremia and type 1 diabetes after kidney-alone (KA) or kidney-pancreas (KP) transplantation. A cross-sectional study comparing two groups of patients with type 1 diabetes was performed. Sixty patients underwent KP transplantation and 30 patients underwent KA transplantation. Age and cardiovascular risk profile were comparable in patients before transplantation. In all patients, atherosclerotic risks factors (lipid profile, fasting and post-methionine load plasma homocysteine, von Willebrand factor levels, D-dimer fragments, and fibrinogen) were assessed and Doppler echographic evaluation of IMT and endothelial function with flow-mediated and nitrate dilation of the brachial artery was performed. Twenty healthy subjects were chosen as controls (C) for EDD. Compared with patients undergoing KA transplantation, patients undergoing KP transplantation showed lower values for HbA1c (KP = 6.2 +/- 0.1% vs. KA = 8.4 +/- 0.5%; P < 0.01), fasting homocysteine (KP = 14.0 +/- 0.7 mcromol/l vs. KA = 19.0 +/- 2.0 micromol/l; P = 0.02), von Willebrand factor levels (KP = 157.9 +/- 8.6% vs. KA = 212.5 +/- 16.2%; P < 0.01), D-dimer fragments (KP = 0.29 +/- 0.02 microg/ml vs. KA = 0.73 +/- 0.11 microg/ml;P < 0.01), fibrinogen (KP = 363.0 +/- 11.1 mg/dl vs. KA = 397.6 +/- 19.4 mg/dl; NS), triglycerides (KP = 122.7 +/- 8.6 mg/dl vs. KA = 187.0 +/- 30.1 mg/dl; P = 0.01), and urinary albumin excretion rate (KP = 13.5 +/- 1.9 mg/24 h vs. KA = 57.3 +/- 26.3 mg/24 h; P < 0.01). Patients undergoing KP transplantation showed a normal EDD (KP = 6.21 +/- 2.42%, KA = 0.65 +/- 2.74%, C = 8.1 +/- 2.1%; P < 0.01), whereas no differences were observed in nitrate-dependent dilation. Moreover, IMT was lower in patients undergoing KP transplantation than in patients undergoing KA transplantation (KP = 0.74 +/- 0.03 mm vs. KA = 0.86 +/- 0.09 mm; P = 0.04). Our study showed that patients with type 1 diabetes have a lower atherosclerotic risk profile after KP transplantation than after KA transplantation. These differences are tightly correlated with metabolic control, fasting homocysteine levels, lower D-dimer fragments, and lower von Willebrand factor levels. Normal endothelial function and reduction of IMT was observed only in patients undergoing KP transplantation.
 ...
PMID:Effects of kidney-pancreas transplantation on atherosclerotic risk factors and endothelial function in patients with uremia and type 1 diabetes. 1124 68

Uncomplicated Type 1 (insulin-dependent) diabetes mellitus is characterized by generalized vasodilatation. Its possible correlates, increased microvascular permeability and endothelial dysfunction, have been associated with long-term complications. The objective was to study the effects of acute hyperglycemia and hyperinsulinemia, both separately and in combination, on skin microvascular flow, capillary permeability, capillary recruitment, and endothelial dysfunction in Type 1 diabetes mellitus. Sixteen Type 1 diabetic patients (all normoalbuminuric, no (pre-)proliferative retinopathy) underwent a euglycemic (glucose target 5.0 mmol/L, insulin infused at 30 mU x kg(-1) x h(-1)), a hyperglycemic (glucose target 12.0 mmol/L, insulin 30 mU x kg(-1) x h(-1)), a hyperinsulinemic (glucose target 5.0 mmol/L, insulin 150 mU x kg(-1) x h(-1)), and a hyperglycemic-hyperinsulinemic (glucose target 12.0 mmol/L, insulin 150 mU x kg(-1) x h(-1)) clamp on separate days, in random order. Skin microvascular flow was measured by laser Doppler flowmetry. Capillary permeability and density were determined by large-window sodium-fluorescein videodensitometry. Increases in serum soluble intercellular adhesion molecule-1 (sICAM-1) and plasma von Willebrand factor antigen (vWF-Ag) were considered to represent abnormal endothelial function. Hyperglycemia (P < 0.01) and hyperinsulinemia (P < 0.05) as well as both interventions combined (P < 0.001) induced an increase in laser Doppler flow, without capillary recruitment. Transcapillary leakage of sodium-fluorescein and sICAM-1 and vWF-Ag levels were unaffected by hyperglycemia or hyperinsulinemia. Microvascular permeability appears to be determined primarily by properties of the capillary wall and not by acute changes in local hemodynamics. The acute hyperglycemia- and hyperinsulinemia-induced vasodilatation is not accompanied by changes in microvascular permeability or endothelial markers.
 ...
PMID:Acute hyperglycemia and hyperinsulinemia enhance vasodilatation in Type 1 diabetes mellitus without increasing capillary permeability and inducing endothelial dysfunction. 1174 67

Endothelial dysfunction occurs early in the development of vascular disease in diabetes. Total plasma homocyst(e)ine (tHcy) is associated with endothelial dysfunction. We therefore aimed to assess endothelial function in children with type 1 diabetes in relation to tHcy and its determinants. Endothelial function was assessed in 36 children with type 1 diabetes aged 13.7 +/- 2.2 years and 20 age- and sex-matched control subjects using ultrasound assessment of flow-mediated dilatation (FMD) and glyceryl trinitrate (GTN)-dependent brachial artery responses. von Willebrand factor (vWF) and thrombomodulin, markers of endothelial activation, were measured in 64 children with type 1 diabetes and 52 control subjects. Fasting glucose, tHcy, serum and red cell folate, vitamin B12, HbA(1c), creatinine, and lipids were also measured. FMD (5.2 +/- 4.7 vs. 9.1 +/- 4.0%, P = 0.002) and the ratio of FMD:GTN-induced dilatation (0.22 +/- 0.39 vs. 0.41 +/- 0.29%, P = 0.008) were significantly lower in diabetic subjects, indicating endothelial dysfunction. In diabetic subjects, red cell folate correlated independently with FMD (beta = 0.42, P = 0.028) and the ratio of FMD:GTN-induced dilatation (beta = 0.59, P < 0.001). Resting vessel diameter correlated independently with tHcy (beta = -0.51, P < 0.001) and height (beta = 0.65, P < 0.001). vWF correlated independently with HbA(1c) (beta = 0.38, P = 0.003), and thrombomodulin correlated independently with red cell folate (beta = -0.38, P = 0.005), tHcy (beta = -0.37, P = 0.004), diastolic blood pressure (beta = -0.28, P = 0.025), and creatinine clearance (beta = 0.26, P = 0.033). Children with type 1 diabetes have early endothelial dysfunction. Better folate status is associated with better endothelial function, as measured by higher FMD, higher FMD:GTN ratio, and lower thrombomodulin. Folate may therefore protect against endothelial dysfunction in children with diabetes.
 ...
PMID:Endothelial dysfunction relates to folate status in children and adolescents with type 1 diabetes. 1208 61

BACKGROUND: Latent tissue scurvy in clinical and experimental ascorbic acid (AA) deficiency resembles diabetic microangiopathy as reflected in capillary hyperperfusion and increased transcapillary escape rate (TER), von Willebrand factor (vWf), and capillary fragility (CF). We aimed to investigate the possible clinical impact of the low plasma AA level observed in type 1 diabetes mellitus. METHODS: Twenty normoalbuminuric patients with retinopathy were included in a randomized, double-blinded, placebo-controlled 6-month study with AA (6 g/day; n=10, mean age+/-S.D. 35.3+/-8.5 years, diabetes duration 17.2+/-3.3 years) or placebo (n=10; mean age 37.8+/-6.6 years, diabetes duration 18.4+/-1.7 years). RESULTS: An inverse correlation between log plasma AA (HPLC method) and TER of (125)I-labelled albumin was found (r=-0.66, p=0.002). TER decreased in the AA-treated group from 6.8+/-1.0 to 5.4+/-1.5%/h compared to the unchanged placebo group (from 5.6+/-1.5 to 5.9+/-1.1%/h; p=0.031). The CF (capillary resistance test) decreased in the AA group compared to the placebo group (p=0.028), while vWf, fibrinogen and fibronectin levels, and glomerular filtration rate (clearance of (125)I-iothalamate) remained unchanged. CONCLUSIONS: The results suggest that a low plasma AA level might be associated (pathogenetic?) with development of microangiopathy in type 1 diabetes mellitus and points to a possible treatment modality.
 ...
PMID:Vitamin C treatment reduces transcapillary escape rate of albumin in type 1 diabetes. 1558 46


<< Previous 1 2 3 Next >>