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V Borcea

Publications and source records attributed to V Borcea.

10 recordsLinked to original sources
PubMed2001

Effect of alpha-lipoic acid on the progression of endothelial cell damage and albuminuria in patients with diabetes mellitus: an exploratory study.

Oxidative stress plays a central role in the pathogenesis and progression of late microangiopathic complications (diabetic nephropathy) in diabetes mellitus. Previous studies suggested that treatment of diabetic patients with the antioxidant alpha-lipoic acid reduce oxidative stress and urinary albumin excretion. In this prospective, open and non-randomized study, the effect of alpha-lipoic acid on the progression of endothelial cell damage and the course of diabetic nephropathy, as assessed by measurement of plasma thrombomodulin and urinary albumin concentration (UAC), was evaluated in 84 patients with diabetes mellitus over 18 months. Forty-nine patients (34 with Type 1 diabetes, 15 with Type 2 diabetes) had no antioxidant treatment and served as a control group. Thirty-five patients (20 with Type 1 diabetes, 15 with Type 2 diabetes) were treated with 600 mg alpha-lipoic acid per day. Only patients with an urinary albumin concentration <200 mg/l were included into the study. After 18 months of follow up, the plasma thrombomodulin level increased from 35.9+/-9.5 to 39.7+/-9.9 ng/ml (P<0.05) in the control group. In the alpha-lipoic acid treated group the plasma thrombomodulin level decreased from 37.5+/-16.2 to 30.9+/-14.5 ng/ml (P<0.01). The UAC increased in patients without alpha-lipoic acid treatment from 21.2+/-29.5 to 36.9+/-60.6 ng/l (P<0.05), but was unchanged with alpha-lipoic acid. It is postulated that the significant decrease in plasma thrombomodulin and failure of UAC to increase observed in the alpha-lipoic acid treated group is due to antioxidative effects of alpha-lipoic acid, and if so that oxidative stress plays a central role in the pathogenesis of diabetic nephropathy. Furthermore, progression of the disease might be inhibited by antioxidant drugs. A placebo-controlled study is needed.

Albuminuria↗
PubMed1999

Peripheral blood mononuclear cells isolated from patients with diabetic nephropathy show increased activation of the oxidative-stress sensitive transcription factor NF-kappaB.

Increased oxidative stress and subsequent activation of the transcription factor NF-kappaB has been linked to the development of late diabetic complications. To determine whether oxidative stress dependent NF-kappaB activation is evident in patients with diabetic nephropathy we used an Electrophoretic Mobility Shift Assay based semiquantitative detection system which enabled us to determine NF-kappaB activation in ex vivo isolated peripheral blood mononuclear cells. We examined 33 patients with diabetes mellitus (Type I and Type II). Patients with diabetic nephropathy showed higher NF-kappaB binding activity in Electrophoretic Mobility Shift Assays and stronger immunohistological staining for activated NF-kappaBp65 than patients without renal complications. NF-kappaB binding activity correlated with the degree of albuminuria (r = 0.316) and with thrombomodulin plasma concentrations (r = 0.33), indicative for albuminuria associated endothelial dysfunction. In a 3 day intervention study in which 600 mg of the antioxidant thioctic acid (alpha-lipoic acid) per day were given to nine patients with diabetic nephropathy oxidative stress in plasma samples was decreased by 48% and NF-kappaB binding activity in ex vivo isolated peripheral blood mononuclear cells by 38%. In conclusion, activation of the transcription factor NF-kappaB in ex vivo isolated peripheral blood mononuclear cells of patients with diabetes mellitus correlates with the degree of diabetic nephropathy. NF-kappaB activation is at least in part dependent on oxidative stress since thioctic acid (alpha-lipoic acid) reduced NF-kappaB binding activity.

Adult↗
PubMed1999

alpha-Lipoic acid decreases oxidative stress even in diabetic patients with poor glycemic control and albuminuria.

In the present cross-sectional study, the influence of alpha-lipoic acid on markers of oxidative stress, assessed by measurement of plasma lipid hydroperoxides (ROOHs), and on the balance between oxidative stress and antioxidant defence, determined by the ratio ROOH/(alpha-tocopherol/cholesterol), was examined in 107 patients with diabetes mellitus. Patients receiving alpha-lipoic acid (600 mg/day for > 3 months) had significant lower ROOHs and a lower ROOH/(alpha-tocopherol/cholesterol) ratio than those without alpha-lipoic acid treatment [ROOH: 4.76 +/- 2.49 vs. 7.16 +/- 3.22 mumol/l; p < .0001] and [ROOH/(alpha-tocopherol/cholesterol): 1.37 +/- 0.72 vs. 2.16 +/- 1.17; p < 0.0001]. In addition, the influence of glycemic control and albuminuria on ROOHs and on the ratio of ROOH/(alpha-tocopherol/cholesterol) was examined in the presence and absence of alpha-lipoic acid treatment. Patients were subdivided into three groups based on (1) their HbA1 levels (< 7.5, 7.5-9.5, and > 9.5%) and (2) their urinary albumin concentrations (< 20, 20-200, and > 200 mg/l). Neither poor glycemic control, nor the presence of micro- or macroalbuminuria prevented the antioxidant effect of alpha-lipoic acid. Using stepwise multiple regression analysis, alpha-lipoic acid was found to be the only factor significantly predicting low ROOHs and a low ratio of ROOH/(alpha-tocopherol/cholesterol). These data provide evidence that treatment with alpha-lipoic acid improves significantly the imbalance between increased oxidative stress and depleted antioxidant defence even in patients with poor glycemic control and albuminuria.

Albuminuria↗
PubMed1999

Influence of ramipril on the course of plasma thrombomodulin in patients with diabetes mellitus.

BACKGROUND: In diabetic patients endothelial dysfunction is reflected by an increased urinary albumine excretion, which can be reduced by ACE-inhibitors. No data are available showing a endothelial-protective effect by determining a marker reflecting endothelial cell-damage. PATIENTS AND METHODS: The effect of angiotensin converting enzyme inhibitor (ACEI) (ramipril) treatment on the progression of endothelial cell damage,--assessed by measurement of plasma-thrombomodulin (TM),--was investigated in an open, non randomized, prospective pilot study over a period of 18 months in diabetic patients. 87 patients with an urinary albumin concentration (UAC) below 100 mg/l at baseline were included. 46 patients were treated without ACEI and served as a control group, 41 patients were treated with ACEI. Participation in this study did not affect intensity in the treatment of blood glucose, blood pressure or diet. At study entry both groups were comparable with respect to duration of diabetes, diabetic complications, vascular risk factors, body mass index, medications used to treat diabetes, presence of hypertension, glycemic control, tryglycerides, HDL cholesterol, creatinine, UAC and plasma-TM. Age, blood pressure, and total cholesterol were significantly higher in the ACEI group, compared with the control group. RESULTS: After a follow up of 18 months a significant increase in UAC (delta UAC = 10.48 mg/l, p = 0.03) and plasma-TM (delta TM = 3.06 ng/l, p = 0.009) was observed in the control group, while in the ACEI treated group a decrease in albuminuria (delta UAC = -7.44 mg/l, p = 0.01) and plasma-TM (delta TM = -4.78 ng/l, p = 0.001) was seen. Despite a similar approach in hypertension and diabetes control in both groups, UAC and plasma-TM decreased after 18 months only in the ACEI treated group. Treatment with ACEI was the strongest predictor (p = 0.0001) indicating decrease of UAC and plasma-TM (multi regression analysis). CONCLUSION: Plasma-thrombomodulin might be a useful marker for assessing the efficacy of drugs potentially protecting the vessel wall. While the present study was a open, non randomized study, further investigation is necessary to proof the hypothesis in a randomized, placebo-controlled, double-blind study.

Adult↗
PubMed1999

The effect of pramlintide (amylin analogue) treatment on bone metabolism and bone density in patients with type 1 diabetes mellitus.

Amylin is a 37-amino-acid peptide related to CGRP and calcitonin. It is co-secreted with insulin from pancreatic beta-cells. Amylin is deficient with type 1 diabetes mellitus. To study the in vivo effects of amylin in humans, diabetic patients are an adequate model of chronic amylin deficiency. We investigated the effect of a 12 months pramlintide therapy (amylin analogue) on bone metabolism in patients with type 1 diabetes mellitus. 23 patients with type 1 diabetes mellitus (age 45.2 +/- 10.3 years, duration of diabetes mellitus 20.7 +/- 9.8 years, 13 male, 10 female) injected themselves 0.1 ml pramlintide, a human amylin analogue, four times per day for a period of 12 months. Bone mineral density measurements of the lumbar spine by dual-energy X-ray absorptiometry (DXA), and biochemical markers of bone metabolism (serum-calcium, PTH, osteocalcin, urinary pyridinium cross-links) were obtained before and one year after starting pramlintide therapy. None of the following parameters changed significantly: bone density, serum calcium, PTH, osteocalcin or pyridinium cross-links. Only osteocalcin decreased from 7.205 ng/ml to 5.825 ng/ml, but this change was not statistically significant. We conclude that a one-year pramlintide therapy does not affect bone density or bone metabolism in patients with type 1 diabetes mellitus without osteopenia (based on the markers used).

Adolescent↗
PubMed1998

Hyperhomocyst(e)inemia and endothelial dysfunction in IDDM.

OBJECTIVE: Considering that elevated blood levels of homocyst(e)ine represent a known independent risk factor for macrovascular disease, we assessed the link between hyperhomocyst(e)inemia and diabetic microvascular complications. RESEARCH DESIGN AND METHODS: Homocyst(e)ine and thrombomodulin plasma levels, a marker of endothelial cell damage, were measured before and 3 h after oral methionine loading in 75 patients with stable, well-controlled IDDM and 40 healthy control subjects matched for sex and age. Exclusion criteria were hyperlipidemia, hypertension, smoking, or positive family history for cardiovascular disease. RESULTS: IDDM patients had higher pre- and postload homocyst(e)ine plasma levels than did healthy control subjects (12.0 vs. 7.7 mumol/l and 27.6 vs. 16.0 mumol/l; P < 0.001). Of 75 IDDM patients, 26 had homocyst(e)ine plasma levels above the normal range (defined as mean +2 SD of values obtained in the control group). The IDDM patients with hyperhomocyst(e)inemia had higher thrombomodulin plasma levels (62.2 vs. 38.2 ng/ml; P < 0.001), higher albumin excretion rates (485 vs. 115 mg/l; P < 0.005), and a higher prevalence of late diabetic complications (nephropathy, 76 vs. 33%; retinopathy, 69 vs. 51%; neuropathy, 57 vs. 41%; macroangiopathy, 57 vs. 33%) compared with IDDM patients with normal plasma homocyst(e)ine. In vitro experiments with human umbilical vein cells show an increased release of thrombomodulin into the culture supernatant only when endothelial cells were pretreated with advanced glycation end product (AGE)-albumin before L-homocystine was added. A synergistic action of homocyst(e)ine and AGEs might contribute to vascular complications of patients with diabetes. CONCLUSIONS: Hyperhomocyst(e)inemia is common in nephropathic diabetic patients and may contribute to the enhanced morbidity and mortality from cardiovascular diseases characteristically observed in IDDM patients with diabetic nephropathy.

Adult↗
PubMed1997

[The Wolfram syndrome: diabetes mellitus, hypacusis, optic atrophy and short stature in STH deficiency].

HISTORY AND CLINICAL FINDINGS: A 43-year-old man was known for 3 years to have diabetes mellitus. For 2 months before admission he had symptoms of hyperglycaemia with polyuria, polydipsia, weight loss, as well as impairment of vision and declining fitness. In addition to bilateral deafness he was clearly of normally proportioned short stature (150 cm). INVESTIGATIONS: The levels of blood sugar (221 mg/dl), HbA1c(10.2%), triglycerides (496 mg/dl) and cholesterol (323 mg/dl) were raised, while the concentration of somatotropic hormone was diminished, both before and after arginine administration. Fundoscopy revealed concentric diminution of the visual fields with left amblyopia. Visual evoked potentials and colour sense testing revealed bilateral optical atrophy, and the audiogram demonstrated deafness. These findings provided the diagnosis of Wolfram syndrome, namely insulin-dependent diabetes mellitus, deafness, optical atrophy and small stature with somatotropic hormone deficiency. TREATMENT AND COURSE: On insulin treatment the metabolic state became normal (HbA1c 7.5%, normal lipid profile). It was decided that the deficiency in somatotropic hormone regulation did not require treatment. CONCLUSION: Cardinal symptoms of the autosomally recessive Wolfram syndrome are insulin-dependent diabetes and optic nerve atrophy. Several types of hormonal abnormalities are associated with it, including a deficiency in the somatotropic axis. To obtain early and adequate hormonal substitution requires extensive endocrinological diagnosis of a disease which frequently becomes manifest in childhood or adolescence.

Adult↗
PubMed1997

Tissue factor antigen is elevated in patients with microvascular complications of diabetes mellitus.

Patients with late diabetic complications have increased levels of parameters indicating activation of coagulation (Takakashi et al., 1989; Ceriello, 1993; Murakami et al., 1993; Kario et al., 1995; Shimizu et al., 1995; Yokoyama et al., 1996), endothelial cell damage (Jensen, 1989; Iwashima et al., 1990; Sernau et al., 1995; Gabath et al., 1996). TF is believed to activate the coagulation mechanism in patients with late complications of diabetes. We studied the TF antigen plasma levels in 72 patients with diabetes mellitus (36 type I, 36 type II) with respect to its relevance as a marker of microvascular diabetic complications. TF levels did not correlate with macrovascular disease, diabetes type or age. Sixty patients with decreased renal function not due to diabetes were studied for evaluation of the contribution of renal failure to TF antigen plasma levels. We did not find a significant correlation of TF with s-creatinine in non diabetic patients (r = 0.27, p > 0.05). However, TF levels were elevated in diabetic patients with microvascular disease. Patients with retinopathy had higher TF levels than without (0.30 ng/ml vs 0.11 ng/ml, p < 0.007). When patients were divided into subgroups according to the urine albumin concentration, TF antigen of patients without albuminuria (0.019 ng/ml, n = 25) did not differ from patients with microalbuminuria (0.095 ng/ml, n = 19 p > 0.05). However, TF levels were significantly higher in patients with macroalbuminuria (n = 28; 0.215 ng/ml, p < 0.005). Thus activation of coagulation in patients with microvascular complications of diabetes may be triggered by tissue factor.

Adult↗
PubMed1997

Hyperhomocyst(e)inemia and endothelial dysfunction in IDDM.

OBJECTIVE: While elevated blood levels of homocyst(e)ine represent an independent risk factor for macrovascular disease, we assessed the link between hyperhomocyst(e)inemia and diabetic microvascular diseases. RESEARCH DESIGN AND METHODS: Plasma levels of homocyst(e)ine and thrombomodulin (TM), markers of endothelial cell damage, were measured before and 3 h after oral methionine loading in 75 patients with IDDM and 40 healthy control subjects matched for sex and age. Exclusion criteria were hyperlipidemia, hypertension, smoking, or positive family history for cardiovascular disease. RESULTS: IDDM patients had higher pre- and postload plasma levels of homocyst(e)ine than did healthy control subjects (12.0 vs. 7.7 mumol/l and 27.6 vs. 16.0 mumol/l; P < 0.001). Of 75 IDDM patients, 26 had plasma homocyst(e)ine levels above the normal range (means +/- 2 SD of values obtained in the control group). These IDDM patients with hyperhomocyst(e)inemia had higher plasma TM levels (62.2 vs. 38.2 ng/ml, P < 0.001), higher albumin excretion rates (485 vs. 115 mg/l, P < 0.005), and a higher prevalence of late diabetic complications (nephropathy, 76 vs. 33%; retinopathy, 69 vs. 51%; neuropathy, 57 vs. 41%; and macroangiopathy, 57 vs. 33%) compared with IDDM patients with normal plasma homocyst(e)ine. In vitro experiments with human umbilical vein cells showed an increased release of TM into the culture supernatant only when endothelial cells were pretreated with advanced glycation end product (AGE)-albumin before L-homocystine was added. A synergistic action of homocyst(e)ine and AGEs might contribute to vascular complications in patients with diabetes. CONCLUSIONS: Hyperhomocyst(e)inemia is common in nephropathic diabetic patients and may contribute to the enhanced morbidity and mortality from cardiovascular diseases characteristically observed in IDDM patients with diabetic nephropathy.

Administration, Oral↗