Comparison of effects of gliclazide, metformin and pioglitazone monotherapies on glycemic control and cardiovascular risk factors in patients with newly diagnosed uncontrolled type 2 diabetes mellitus.

OBJECTIVE: The objective of this study was to evaluate and compare the effects of gliclazide-modified release (gliclazide-MR), metformine (MET) and pioglitazone (PIO) monotherapies on glycemic control and conventional/non-conventional cardiovascular risk factors in patients with newly diagnosed type 2 diabetes mellitus (T2DM). MATERIAL AND METHODS: A single center, randomized, 52-wk comparator-controlled clinical study was carried out in patients with newly diagnosed uncontrolled T2DM. A total of 57 patients were randomized into gliclazide-MR, metformin and pioglitazone groups. Drugs were administered for 12 months. Anthropometric measurements, fasting plasma glucose (FPG), postprandial plasma glucose (PPG), HbA1c, insulin, HOMA-IR, lipid parameters, the markers of coagulation/fibrinolysis, inflammation and endothelial dysfunction were measured at baseline and at months 3, 6, and 12. RESULTS: In the gliclazide-MR group, HC, FPG, HbA1c, insulin, HOMA-IR, TC, trigylcerides, Lp (a), E-selectin and Hcy were significantly decreased after treatment compared to baseline. In the MET group, BMI, WC, FPG, PPG, HbA1c, ICAM-1 and Hcy significantly decreased after treatment compared to baseline. In PIO group, WC, HC, FPG, PPG, HbA1c, C-peptid, HOMA-IR, trigylcerides, vWF, IL-6, ICAM-1, E-selectin and Hcy significantly decreased after treatment compared to baseline, whereas, HDL-C increased. At the end of the month 12, the decreases in insulin and HOMA-IR score were more pronounced with PIO compared to gliclazide. CONCLUSIONS: Gliclazide-MR, MET and PIO monotherapies, were equally effective in proving glycemic control in patients with newly diagnosed, oral antidiabetic (OAD)-naive T2DM. But, improvements in conventional/non-conventional cardiovascular risk factors were more pronounced in patients on PIO therapy compared to gliclazide and MET therapies. Also, all of the 3 drugs represent effective and safe first-line pharmacological treatment options in these patients.

Preventive and protective effects of Turkish propolis on H2O2-induced DNA damage in foreskin fibroblast cell lines.

The aim of the present study was to evaluate the potential of Turkish propolis extracts if they prevent or protect foreskin fibroblast cells against hydrogen peroxide (H2O2)-induced oxidative DNA damage. Hydrogen peroxide (40 µM) was used as an inducer of oxidative DNA damage. The damage of DNA was evaluated by using the alkaline single cell gel electrophoresis (comet) assay. Turkish propolis extracts at concentrations of 25, 50, 75 and 100 µg/ml were prepared by ethanol. Anti-genotoxicity was assessed before, simultaneously, and after treatment of propolis extract (50 µg/ml) with H2O2. The results showed a significant decrease in H2O2-induced DNA damage in cultures treated with propolis extract. The antioxidant activity of phenolic components found in propolis may contribute to reduce the DNA damage induced by H2O2. Our findings confirmed the chemopreventive activity of propolis and showed that this effect may occur under different mechanisms.

Increased serum anti-carbonic anhydrase II antibodies in patients with Graves' disease.

Carbonic anhydrase II (CA II) has an important role in thyroid hormone synthesis via regulating iodide (I-) transport across thyroidal cell membranes and the existence of autoantibodies against CA I and/or CA II have been shown in sera from patient with various autoimmune diseases such as Sjögren's Syndrome, Systemic Lupus Erythmatosus, type 1 diabetes, primary biliary cirrhosis and ulcerative colitis. The aim of this study was to investigate the presence of anti-CA I and CA II antibodies in autoimmune thyroid disease and the relationships between the autoantibodies and other clinical parameters. We studied 40 autoimmune thyroid patients (20 Hashimoto's thyroiditis, HT and 20 Graves' disease, GD ) and 21 healthy control subjects. Serum anti-CA I and CA II antibodies were screened by ELISA. Positive rate of anti-CA II (25%) antibody was significantly higher in GD patients as compared to HT patients and control subjects (p<0.05). There were no significant changes in positive rate of anti-CA I antibody. In addition, a significant correlation between serum anti-CA antibodies titers and other studied clinical parameters was not found. The results suggest that anti-CA II antibodies may be involved in the pathogenesis of GD.

Iodine status, thyroid function, thyroid volume and thyroid autoimmunity in patients with type 1 diabetes mellitus in an iodine-replete area.

OBJECTIVE: To analyze the prevalence and clinical significance of thyroid autoimmunity, thyroid volume and iodine status in patients with type 1 diabetes mellitus compared with age and sex matched healthy controls, in an iodine-deficiency improved area. METHOD: Fifty-eight patients with type 1 DM, 30 female and 28 male, who attended the pediatric endocrinology clinic of Karadeniz Technical University Hospital were included into the study. They were compared with 58 healthy children matched for sex and age. Routine thyroid function parameters, thyroid autoantibodies (TPOAb, TGAb and TRAb) and urinary iodine excretion were measured and thyroid volume was determined by ultrasonography (US). RESULTS: Twenty-six patients (44.8%) in diabetic patients and 20 subjects (34.5%) in the control group had thyroid autoantibody positivity. TPOAb and TGAb positivity were significantly high in diabetic patients (P=0.01 and P=0.032, respectively). Thyroid US revealed a thyroid volume of 6.6+/-3.5 ml (median 6.4 ml, range 1.117.2 ml) in the diabetic patients compared with 3.7+/-2 ml (median 3.1 ml, range 0.8-8.6 ml) in the control group (P=0.0001). Median urinary iodine levels of both groups were clearly above the threshold level for iodine deficiency, but 26 patients with type 1 DM (44.8%) and 16 controls (27.5%) had urinary iodine excretion below 100 microg/L, and 21 (36.2%) of diabetic patients and two subjects (3.4%) of the control group were consistent with severe iodine deficiency. No significant differences were noted in diabetic patients in terms of age, duration and metabolic control of the disease and thyroid volume when compared according to the autoantibody presence. Additionally, there were no significant differences between the iodine deficient and iodine sufficient diabetic patients in terms of age, sex, duration of disease, HbA1c, thyroid hormones and thyroid volumes. Thyroid autoimmunity was lower in patients with iodine deficiency (38.4% vs. 50%), but not statistically significant. CONCLUSION: We found that type 1 DM patients had larger thyroid volume compared with healthy control groups, and a large portion of them had the markers of autoimmune thyroid disease and iodine deficiency. Surprisingly, we found that a large portion of the healthy children had TRAb positivity. We proposed that TRAb must be considered in community surveys or prevalence studies of autoimmune thyroid disorders in iodine-replete areas. Additionally, prospective longitudinal studies are needed to determine the clinical significance of TRAb positivity in diabetic patients.

Effects of combined nutritional therapy on acute necrotizing pancreatitis in rats in the early phase of the disease.

The aim of this study was to investigate the influence of a small amount of enteral nutrition along with parenteral nutrition on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats in the early phase of disease. The induction of ANP resulted in a significant increase in mortality rate, intestinal permeability, bacterial infection in the pancreas and extrapancreatic organs, pancreatic necrosis and serum activity of urea and amylase, and a significant decrease in concentrations of calcium, protein and albumin. But no difference was observed between the pancreatitis groups. Significant hyperglycemia and increased liver transaminase activity were observed in rats treated with combined nutritional therapy (CNT). CNT did not improve the course of acute pancreatitis, intestinal permeability, bacterial translocation, or reduce the extent of acinar cell injury in ANP and is therefore unlikely to be of benefit in patients with pancreatitis in the early period.

Blood coagulation and fibrinolytic activity in hypothyroidism.

The influence of hypothyroidism on haemostasis is controversial; both hypocoagulable and hypercoagulable states have been reported. Hypothyroidism has been associated with atherosclerosis; a hypercoagulable state in addition might represent a risk factor for thromboembolic disease. The aim of the present study was to investigate the markers of endogenous coagulation and vascular endothelial cell function and to evaluate the relationship between serum lipid profile, thyroid hormones and haemostatic parameters in hypothyroid patients. We investigated various haemostatic parameters in 20 patients with hypothyroidism and compared them with 20 euthyroid controls. The relationship between serum thyroid hormones and the haemostatic parameters was examined. The plasma levels of fibrinogen, AT III and PAI-1 were significantly increased in hypothyroid patients compared with the control group, whereas factors VIII and X activity was decreased. We showed that free T3 levels correlated with factor IX activity. Free T4, FT3 and TSH did not correlate with fibrinogen, vWF, AT III, t-PA, or PAI-1. aPTT correlated inversely with t-PA activity and positively with protein C activity. Anti-Tg correlated inversely with FV. There was a positive correlation between triglycerides and protein C. Protein S correlated inversely with high density lipoprotein cholesterol. We found a hypofibrinolytic state in patients with hypothyroidism. Our results suggest that the risk of developing thrombosis and ultimately myocardial infarction via high PAI-1 levels may be increased in patients with hypothyroidism, a result in line with recent epidemiological data. However, thyroid hormones may play a role at different levels of the complex haemostatic system.

Blood coagulation and fibrinolysis in patients with hyperthyroidism.

Several papers concerning abnormalities of blood coagulation and fibrinolysis during hyperthyroidism, have been published. Increased von Willebrand Factor (vWF) activity and high fibrinogen levels have been reported. However, there is controversy concerning the presence of a hypercoagulable state in hyperthyroidism. We investigated various hemostatic parameters in 41 hyperthyroid patients and compared them to 20 euthyroid controls. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, factors V, VII, VIII, IX and X activities, vWF, antithrombin III (AT III), protein C, protein S, tissue plasminogen activator (t-PA) and tissue plasminogen activator inhibitor-1 (PAI-1), as well as common lipid variables, were measured. The relationships between serum thyroid hormones and these hemostatic parameters were examined. Compared with control subjects, fibrinogen, factor IX, vWF, AT III and PAI-1 were significantly increased in patients (p<0.05, p<0.0001, p<0.05, p<0.01 and p<0.0001; respectively), whereas factor X and t-PA were decreased (p<0.05). We showed that free T4 (FT3) levels were correlated with factor VIII activity (r=0.35, p<0.05). FT4, FT3 and TSH did not correlate with fibrinogen, vWF, AT III, t-PA, or PAI-1. AT III was inversely correlated with factor VII activity (r=-0.48, p<0.01). Protein C and S were correlated with vWF levels (r=0.58, p<0.0001; r=0.55, p<0.0001, respectively). Protein C was inversely correlated with t-PA (r=-0.39, p<0.01). There was a negative correlation between triglycerides, LDL-C and F X (r=-0.45, p<0.05; r=-64, p<0.01, respectively). Mean platelet volume (MPV) was correlated with anti-thyroid peroxidase (TPO) antibodies (in Graves'disease) and F IX activity (r=0.57, p<0.05 and r=0.39, p<0.05; respectively). We found important differences in the coagulatory /fibrinolytic parameters between the hyperthyroid patients and healthy controls. Hyperthyroid patients may experience vascular endothelial dysfunction and decreased fibrinolytic activity in blood. This endothelial activation may represent a situation with a higher thromboembolic potential.

Prevalence of diabetes, obesity and hypertension in a Turkish population (Trabzon city).

OBJECTIVE: The objectives of this study were to determine the prevalence of diabetes mellitus in Trabzon city, Turkey, using standardized diagnostic criteria, and to evaluate associated factors. METHODS: A total of 3000 eligible study subjects were selected. Of those, 2646 subjects participated in the study. Individuals aged > or =20 years were selected from their family health cards and were invited to the health station. Anthropometric and demographic data were obtained for each subject. Plasma glucose was measured by an autoanalyser. People without previously diagnosed diabetes were categorized according to WHO diagnostic criteria as follows. Diabetes: a fasting plasma glucose (FPG)> or =140 mg/dl or 2-h plasma glucose > or =200 mg/dl after a 75-g oral glucose load. RESULTS: The overall prevalence of diabetes in those > or =20 years of age was 6.0% (n=160). Among diabetic subjects, 69 were newly diagnosed diabetes mellitus. Age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP) and FPG were higher in diabetic subjects than in non-diabetic subjects. The prevalence of diabetes showed significant association with increased age (P<0.0001). The overall prevalence of obesity was 19.2%. The combined prevalence of both overweight and obesity was 60.6%. The prevalence of obesity was 27.4% among women and 10.7% among men (P<0.0001). Prevalence of diabetes increased with degree of obesity (P<0.0001). The rate of obesity in diabetic subjects was 35.6%. In the study population as a whole, the prevalence of obesity increased with age, being highest in the 50-59 years age group, but lower again in the 60+ age group. Prevalence of SBP> or =140 mmHg was 12.0% and of DBP> or =90 mmHg was 8.2%.

The effect of ATP-MgCl(2) on prevention of reperfusion injury after unilateral testicular torsion.

This study was designed to investigate the effect of ATP-MgCl(2) administered before and after detorsion on the prevention of reperfusion injury after unilateral testicular torsion. The rats were divided into six groups, each containing six rats. Torsion was created by rotating the left testes 720 degrees in a clockwise direction. Group 1 functioned as a control group. Torsion only was carried out in Group 2. Detorsion was carried out in Group 3. ATP-MgCl(2) (100 micromol/kg) was injected intravenously immediately before detorsion in Group 4. ATP-MgCl(2) (100 micromol/kg) was injected intravenously immediately after detorsion in Group 5. Saline was injected intravenously immediately after detorsion in Group 6. The effect of ATP-MgCl(2) on reperfusion injury was investigated by determining the levels of thiobarbituric acid-reactive substances (TBAR) and resulting lipid peroxidation in the bilateral testicular tissue. Testicular torsion and detorsion caused a significant increase in the TBAR levels in the bilateral testicular tissue. TBAR levels decreased to approximately normal levels in Groups 4 and 5. It is concluded that if reperfusion injury has occurred in both testes after unilateral testicular torsion, ATP-MgCl(2) administered before or after detorsion may prevent reperfusion injury in testicular torsion.

The effects of impaired trace element status on polymorphonuclear leukocyte activation in the development of vascular complications in type 2 diabetes mellitus.

Impaired trace element metabolism may be involved in some of the metabolic dysfunctions, and contribute to the development of vascular complications in diabetic patients. In order to investigate the relationships among diabetes mellitus, trace element status, leukocyte activation and vascular complications, 55 type 2 diabetic patients (34 with vascular complications and 21 without vascular complications) and 50 non-diabetic control subjects were studied. The mean leukocyte count (p<0.001), polymorphonuclear elastase (p<0.001), erythrocyte malondialdehyde (p<0.001), and glycated haemoglobin (p<0.001) levels, and copper/ zinc ratio (p<0.001) were found to be higher in diabetic patients than in the control group, but serum zinc levels (p<0.001) and erythrocyte superoxide dismutase activities (p<0.001) were lower, and serum copper levels showed no differences. In patients with vascular complications, the mean leukocyte count (p<0.05), zinc (p<0.05), polymorphonuclear elastase (p<0.05), erythrocyte malondialdehyde (p<0.001) and glycated haemoglobin (p<0.05) levels, and copper/zinc ratio (p<0.001) were significantly different from those patients without complications. Closer correlations between the copper/zinc ratio and polymorphonuclear elastase (r=0.82, p<0.01), erythrocyte malondialdehyde (r=0.46, p<0.05) or erythrocyte superoxide dismutase (r= -0.85, p<0.01) were found in patients with vascular complications compared to those without, and all of those showed significant relationships with poor glycaemic metabolic control. We conclude that zinc deficiency may provoke polymorphonuclear leukocyte activation, and contributes to the development of vascular complications in type 2 diabetic patients. Furthermore, copper/zinc ratio and polymorphonuclear elastase may be used as important markers to evaluate the presence of vascular complications.

Antioxidative enzyme activities and lipid peroxidation in major depression: alterations by antidepressant treatments.

BACKGROUND: Reactive oxygen species (ROS) may play a role in some neuropsychiatric disorders. There is some evidence that the activation of immune-inflammatory process, increase of monoamines catabolism, and abnormalities in lipid compounds may cause overproduction of ROS and, in turn, antioxidative enzyme activities (AEAs) and lipid peroxidation (LP), and that these phenomena may be related to pathophysiology of major depression. METHODS: The aims of this study were (i) to examine the AEAs and LP levels of the major depressed (MD) patients, and to compare these with healthy controls; and (ii) to investigate the effect of subchronic treatment with selective serotonin reuptake inhibitors (SSRIs) on AEAs and LP levels in MD subjects. Thirty MD patients, and 32 healthy controls (HC) participated in this study. AEAs and LP levels were determined by measuring several antioxidative enzymes and malondialdehyde (MDA) levels in plasma and/or in red blood cells. RESULTS: Major depressed patients, especially melancholic patients, had higher AEA and LP levels than those of healthy controls. After treatment for 3 months with SSRIs, AEA and LP levels of the patients were significantly decreased to normal levels. CONCLUSION: These findings suggest that (i) major depression, especially with melancholia, is associated with elevated AEAs and LP, and that (ii) subchronic treatment with SSRIs may have a suppressive effect on AEA and LP. CLINICAL IMPLICATION AND LIMITATION: AEAs might be used for monitoring SSRIs effects.

Effects of dopexamine on acute necrotising pancreatitis in rats.

OBJECTIVE: To examine the effects of dopexamine on pancreatic tissue oxygen tension (PtO2) and the extent of acinar injury in rats with acute necrotising pancreatitis DESIGN: Laboratory study. SETTING: Medical school, Turkey. ANIMALS: 68 Sprague Dawley rats. MAIN OUTCOME MEASURES: Cardiorespiratory measurements, pancreatic PtO2, effects on activity of serum amylase and concentration trypsinogen activation peptide (TAP). and histological picture. RESULTS: The four study groups (sham + saline, sham + dopexamine, acute pancreatitis and acute pancreatitis + dopexamine) were each divided into two; in 9 rats in each, pancreatic biochemistry was studied, and in the remaining 8 in each group serum biochemistry and histology were studied. The groups were comparable with regard to mean arterial pressure, heart rate, arterial blood gases, packed cell volume, and serum amylase activity. The use of dopexamine increased pancreatic PtO2 in the sham + dopexamine group without the important blood pressure changes. The induction of pancreatitis resulted in a significant reduction in pancreatic PtO2 in the pancreatitis groups. The use of dopexamine did not increase pancreatic PtO2. There were no significant differences in plasma TAP concentration and the extent of acinar cell injury in the animals in the pancreatitis groups. CONCLUSION: Treatment with dopexamine does not improve the pancreatic microcirculation or reduce the extent of acinar cell injury in acute necrotising pancreatitis and is therefore unlikely to be of benefit in patients with pancreatitis.

Effects of antidepressant treatments on polymorphonuclear elastase levels in patients with depression.

BACKGROUND: We have previously reported that severe depression is associated with immunological and inflammatory alterations and these alterations may be showed easily by polymorphonuclear elastase (PMNE) measurements. The purpose of the present study is to show how PMN elastase levels change before and after antidepressant treatment. METHODS: Fifty-five patients with depression (40 with major depression [MD], 15 with dysthymic disorder [DD]) were included in the study. Blood samples were drawn prior to drug treatment, and 3 months after the treatment. Severity of depression was measured by 24-item Hamilton depression rating scale (HDRS). RESULTS: There was a positive correlation between Delta PMNE levels and Delta HDRS in patients with MD, but not in patients with DD. Twenty-eight patients were given moclobemide, and 27 patients were given imipramine. It was seen that PMN elastase levels were significantly reduced after 3-month antidepressant treatment period only in patients with MD. CONCLUSION: These findings suggest that PMNE activity is a state dependent parameter and improvement of depressive symptoms due to antidepressant treatment may lead to decrement of PMNE levels. CLINICAL IMPLICATION AND LIMITATIONS: PMN elastase measurements may be used as a sensitive biological marker to follow the time-course of the disease activity in patients with major depression.

Plasma lipoprotein (a) levels in Turkish NIDDM patients with and without vascular diabetic complications.

OBJECTIVE: Plasma concentrations of lipoprotein (a) [Lp(a)], an independent risk factor for atherosclerosis, were measured in 59 non-insulin-dependent diabetes mellitus (NIDDM) patients with and without vascular complications, and 21 non-diabetic healthy subjects. RESULTS: The plasma log Lp(a) levels were found to be significantly increased in the NIDDM patients (1.40 +/- 0.36) compared with the healthy subjects (1.02 +/- 0.53; p < 0.05). Plasma Lp(a) levels in NIDDM patients with diabetic vascular complications (1.51 +/- 0.27) were significantly higher than those of the NIDDM patients without diabetic vascular complications (1.23 +/- 0.43) and healthy subjects (p < 0.05). There were significant correlations between plasma log Lp(a) levels and apolipoprotein B (apo B) in all NIDDM patients (r: 0.68, p < 0.05). No correlation was observed between Lp(a) levels and age, sex, duration of diabetes, fasting blood glucose, haemoglobin Alc, the mode of treatment, triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and apolipoprotein Al levels in all patients. CONCLUSIONS: It was concluded that Lp(a) was a risk factor for angiopathy in NIDDM patients and the patients who have a high plasma Lp(a) concentration should be kept under strict glycaemic control.

The significance of autoantibodies against oxidatively modified low-density lipoprotein (LDL) in patients with psoriasis.

Psoriasis is associated with changes in plasma lipid and lipoproteins, which may play a role in the development of occlusive vascular disease. The oxidation of low-density lipoprotein (LDL) is considered a key event in the development and progression of atherosclerosis. Autoantibodies against oxidized LDL (auAb-oxLDL) may contribute to understanding the relationship between oxidative processes and development of atherosclerosis. Thirty-three patients with psoriasis and 30 matched control subjects were investigated. LDL oxidation was evaluated as the presence of autoantibodies against LDL oxidatively modified with Cu++, by an ELISA system in the patients and control sera. AuAb-ox LDL levels of the patients were found to be significantly increased compared with a control group. 42% of the patients and 3.3% of the control subjects had higher auAb-ox LDL levels than the cut-off point (352 mU/ml). The levels of auAb-ox LDL were found to be correlated with PASI score (r = 0.67, p < 0.01). Also, The antibody level was found to be correlated with polymorphonuclear elastase and alpha-1 antitrypsin levels (r = 0.58, p < 0.05; r = 0.51, p < 0.05, respectively). It was concluded that increased levels of auAb-oxLDL in the psoriatic patients may be a consequence of the interaction between imbalance of oxidant-antioxidant system and lipoproteins, and the measurement of auAb-oxLDL in the patients may mirror in vivo occurrence of oxidative processes.

Autoantibodies against oxidatively modified low-density lipoprotein in patients with Behçet's disease.

BACKGROUND: Change of lipids and lipoprotein metabolism and an imbalance of the oxidant-antioxidant system related to the disease activity have been reported in Behçet's disease. Therefore, there is a tendency of oxidative modification of lipids and lipoproteins in patients with the disease. OBJECTIVE: To investigate serum autoantibodies against oxidatively modified low-density lipoprotein (oxLDL) as a marker for the degree of in vivo oxidation of lipoproteins in Behçet's disease. METHODS: Serum autoantibodies against oxLDL, total cholesterol, triacylglycerol, HDL cholesterol, LDL cholesterol, apolipoprotein (Apo) AI, Apo B, alpha1-antitrypsin, alpha2-macroglobulin and erythrocyte sedimentation rate were determined in 37 patients and 30 sex- and age-matched healthy volunteers. Autoantibodies against oxLDL were measured by a commercial enzyme-linked immunosorbent assay. RESULTS: Serum autoantibody levels against oxLDL were significantly higher in patients than in controls (425 +/- 365 and 187 +/- 132 mU/ml, respectively; p < 0.05). The levels of autoantibodies against oxLDL in the patients were found to correlate with total cholesterol, LDL cholesterol, HDL cholesterol and alpha1-antitrypsin levels (r = 0.38, p < 0.05; r = 0.42, p < 0.05; r = -0.38, p < 0.05; r = 0.42, p < 0. 05, respectively). CONCLUSION: It has been shown in previous studies that high autoantibody titers against oxLDL may be important in diseases with atherosclerosis as seen in systemic lupus erythematosus and rheumatoid arthritis. High autoantibody titers against oxLDL are not specific for Behçet's disease but probably important for pathologic processes in the disease. We suggest that increased levels of autoantibodies against oxLDL may be a factor responsible for endothelial dysfunction and development of vascular pathology in Behçet's disease.

Plasma lipoprotein (a) concentrations in hypothyroid, euthyroid and hyperthyroid subjects.

OBJECTIVE: Alterations of the lipid profile are a well known phenomenon in thyroid dysfunction. Thyroid hormones regulate lipid metabolism through various mechanisms, but a key role is played by the LDL receptor pathway. Thyroid hormone influence on lipoprotein (a) [Lp(a)] metabolism is known. METHODS AND RESULTS: Therefore we studied Lp(a) concentrations in a group of 16 hypothyroid patients and in a group of 22 hyperthyroid patients. Twenty-six euthyroid subjects were used as a control group. Plasma Lp(a) concentrations in hyperthyroid patients (23.2 +/- 28.1 mg/dl) were significantly lower than those of the hypothyroid patients (27.1 +/- 19.2, p < 0.05). There were negative correlations between plasma Lp(a) concentrations and total T4 levels in patients with hyperthyroidism and hypothyroidism (r: -0.49, p < 0.05; r: -0.40, p < 0.05, respectively). Also, decreased HDL-C levels, increased LDL-C, total cholesterol and apo B levels in the hypothyroid patients according to euthyroid subjects were observed (p < 0.05). Decreased LDL-C levels, increased HDL-C and apo Al levels in the hyperthyroid patients according to euthyroid subjects were determined (p < 0.05). CONCLUSIONS: It was concluded that plasma Lp(a) concentrations increase in hypothyroid patients and the observed relationships between thyroid status and Lp(a) levels can be explained by impaired catabolism of apo B and Lp(a) in hypothyroidism.

Decreased neutrophil antioxidative enzyme activities and increased lipid peroxidation in hyperlipoproteinemic human subjects.

Neutrophils have the capacity to produce free radicals. Free radicals are associated with hyperlipoproteinemia and atherosclerotic processes. For this reason, neutrophil superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione reductase (GR), catalase (Cat) activities and thiobarbituric acid reactive substances (TBARS), as an index of lipid peroxidation, have been studied in hyperlipoproteinemic (HLP) and age-matched normolipidemic groups. Lipid parameters including triglycerides, total cholesterol, plasma TBARS, HDL-cholesterol, LDL-cholesterol, apo A-I, apo B have also been determined. Forty subjects (females 18, males 22) with HLP (mean age 43.8+/-8.7 (S.D.)) and 40 normolipoproteinemic subjects (females 17, males 23; mean age 46.4+/-11) were included in the study. Neutrophils were isolated by Percoll gradient centrifugation from venous blood samples. Methods used were as follows: INT method for SOD, UV method at 340 nm based on oxidation of NADPH for GSH-Px and GR, UV method at 240 nm based on degradation of hydrogen peroxide for catalase, and a method based on reaction with thiobarbituric acid for TBARS. Neutrophil SOD, GSH-Px, and catalase activities were found to be significantly low in the hyperlipoproteinemic group compared with the normolipoproteinemic group. GR activity did not differ between both groups. The mean TBARS level in the neutrophil fraction was found to be significantly higher in hyperlipoproteinemics than in that of the normolipoproteinemics. It was concluded that decreased neutrophil antioxidant enzyme activities in hyperlipoproteinemics may lead to insufficient detoxification of free radicals produced in these cells and contribute to increased lipid peroxidation.