Biotransformation and toxicity effect of monoanthraquinone dyes during Bjerkandera adusta CCBAS 930 cultures

The aim of this study was to evaluate of possibility of biotransformation and toxicity effect of monoanthraquinone dyes in cultures of Bjerkandera adusta CCBAS 930. Phenolic compounds, free radicals, phytotoxicity (Lepidium sativum L.), ecotoxicity (Vibrio fischeri) and cytotoxicity effect were evaluated to determine the toxicity of anthraquinone dyes before and after the treatment with B. adusta CCBAS 930. More than 80% of ABBB and AB129 was removed by biodegradation (decolorization) and biosorption, but biodegradation using oxidoreductases was the main dye removing mechanism. Secondary products toxic to plants and bacteria were formed in B. adusta strain CCBAS 930 cultures, despite efficient decolorization. ABBB and AB129 metabolites increased reactive oxygen species (ROS) production in human fibroblasts, but did not increase LDH release, did not affect the resazurine reduction assay and did not change caspase-9 or caspase-3 activity.

Activity of antioxidant enzymes in children from families at high risk of premature coronary heart disease

A positive family history of coronary heart disease (CHD) is one of the most predictive risk factors of CHD. Many children with increased risk of CHD because of their positive family history of CHD do not present other risk factors, such as altered serum lipid profile. Oxidative stress plays an important part in the pathogenesis of atherosclerosis. Serum antioxidants and intracellular enzymatic antioxidants composed mainly of glutathione peroxidase (GSH-Px), catalase (CAT), superoxide dismutase (SOD) and glutathione reductase counterbalance oxidative stress. Diminished activity of this system may lead to accelerated progression of atherosclerosis. The aim of this study was to assess the activity of CAT, GSH-Px, SOD and glutathione reductase in children with a family history of premature CHD who did not present any other major risk factors of CHD (diabetes, obesity, dyslipidaemia or hypertension). Twenty-two healthy children from high-risk families, selected according to the National Cholesterol Education Program definition, were enrolled in the study. The control group comprised 18 children without a family history of CHD. All the children were healthy and had been screened for hyperlipidaemia, diabetes, hypertension and obesity prior to the study. The erythrocyte activity of CAT, GSH-Px, SOD and glutathione reductase was assessed. Children at high risk of CHD had a statistically significant lower level of GSH-Px and CAT activity than the children in the control group. There were no statistically significant differences in the activity of SOD and glutathione reductase.

Plasma levels of von willebrand factor, endothelin-1, prostacyclin and thromboxane in children from families with high risk of premature coronary artery disease

The aim of the study was to assess the plasma levels of endothelial injury markers in children from families with high risk of premature coronary heart disease (CHD) without other common CHD risk factors (hyperlipidaemia, obesity, hypertension, low physical activity). The study comprised 48 children, including 24 children from high-risk families (HR), according to the NCEP (National Cholesterol Education Programme) criteria: one or two parents had clinical manifestation of cardiovascular disease before the age of 65 years (mother) or 55 years (father). The control group included 24 healthy children with no familial history of cardiovascular disease. All the children were normolipidaemic according to the NCEP and the European Atherosclerosis Society criteria for children aged 2-19 years. In the HR group, the concentration of vWf was significantly elevated in comparison to that in the control group (p<0.0001). Plasma concentrations of ET-1 and TxB2 did not differ significantly between the HR group and the controls. Plasma concentrations of the 6-ketoPGF1alpha in the HR group and in the respective age and gender HR subgroups were significantly lower compared with those of the control group (p<0.00005). Concentration of vWf in the HR group was negatively correlated with the concentration of 6-ketoPGF1alpha (r = -0.47; p<0.05) and positively correlated with TxB2 (r=0.39; p<0.01). In a logistic regression analysis, we found that the 6-ketoPGF1alpha concentration in the lower quartile (< 16.1 pmol/L) was associated with a 3.4-fold odds of inclusion in the high-risk group versus the upper quartile (>23.0 pmol/L).

[HMG-CoA reductase inhibitors in prevention of cardiovascular diseases: new mechanisms, aspects and trials]

Use of lipid-lowering drugs in both primary and secondary prevention of cardiovascular disease (CVD) decreases significantly risk of myocardial infarction, stroke, incidence of cardiovascular events, reduces the cardiovascular mortality and morbidity as well as total mortality. HMG-CoA reductase inhibitors (statins) are most potent cholesterol-lowering drugs. Statins act by inhibition of HMG-CoA reductase activity, a rate--limiting step in synthesis of cholesterol and important metabolites of mevalonate--isoprenoids. The mechanisms by which favourable antiatherogenic actions of statins occur are complex. Statins inhibit proliferation and migration of vascular smooth muscle cells, reduce free-radicals generation and LDL modification, lower Lp(a) concentration, inhibit macrophage-derived foam cells accumulation and inhibit activation of platelets, thromboxane and PAI-1 synthesis. Use of statins in the therapy of hypercholesterolemia is presently recommended by NCEP, especially in high-risk groups (diabetes, post-CABG and PTCA, kidney and heart transplantation). Nevertheless, patients with CAD and moderately elevated LDL-C levels also benefit from the treatment with statins. Because of high costs of the therapy, statins of most favourable pharmacoeconomic profile should be used.

[Genetic predisposition to cardiovascular diseases]

The development of cardiovascular system disorders depends on both environmental and genetic factors. Precise mechanism by which genetic factors may promote atherosclerotic lesion formation is still under investigation. From multiple candidate genes for cardiovascular disorders the special attention should be paid to that which control synthesis of molecules involved in atherosclerosis process. For now lots of experiments have been done to test specific genes speculated to be crucial for the onset and progression of atherosclerosis, including genes of lipoprotein metabolism, coagulation and fibrinolysis system, renin-angiotensin system and substances influencing the metabolism of arterial wall. Many of them showed the association between tested polymorphisms and pathogenesis of cardiovascular diseases.

[The influence of angiotensin-converting enzyme inhibitors on collagen content of the aorta wall in experimental hypercholesterolemia]

In atherosclerosis numerous qualitative and quantitative changes in connective tissue metabolism parameters in serum and aorta occur. In atherosclerosis there is an enhanced activity of local renin-angiotensin systems. It leads to overexpression of ANG II, both in serum and arterial wall. ANG II stimulates SMC to over-synthesize the collagens type I and III. Hyper-cholesterolemia is a form of metabolic injury which can both induce phenotypic change of SMC and activate RA system in arterial wall. ACEI lower the accumulation of collagens type I and III, and enhance elastin content in arterial wall in experimental hypertension. The aim of this study was to assess the influence of captopril, enalapril and quinapril on connective tissue metabolism of the aorta in experimental hyper-cholesterolemia. 64 male New Zealand rabbits were used. Animals were fed with standard fodder, special diet (1% cholesterol content) or special diet + tested ACEI. Two doses of ACE inhibitors were used: 1st--equivalent to doses applied to human subjects (in mg/kg of body weight), 2nd--dose 10 times higher. The animals were divided into 8 equal groups: K--standard fodder, B--special diet, C1, C2--special diet + captopril in doses 2.5 and 25 mg/kg/24 hours, respectively, E1, E2--special diet + enalapril in doses 0.75 and 7.5 mg/kg/24 hours, respectively, Q1 i Q2--special diet + quinapril in doses 0.75 and 7.5 mg/kg per day, respectively. The experiment lasted for 6 months. After 24 weeks the animals were sacrificed and aortae were excised for collagens assay. The statistical analysis was performed using ANOVA, followed by LSD test; p < 0.05 was considered statistically significant. The aorta collagens content of cholesterol-fed rabbits significantly increased. The tested ACEI (captopril, enalapril in both doses and quinapril in lower dose) had a preventive effect against the increase of aorta collagen content.

[Anti-atherosclerotic actions of HMG-CoA reductase inhibitors]

Statins are most potent lipid-lowering drugs. The mechanisms of their action is specific inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) activity. HMG-CoA reductase catalyses the reduction of HMG-CoA o mevalonate and is rate-limiting step in cholesterol biosynthesis pathway. Mevalonate is considered to be not only an important intermediate of cholesterol synthesis, but also the source of isoprenoids which play important role in DNA replication and cell growth. It was shown that statins inhibit the proliferation and migration of vascular smooth muscle cell--key events in atherogenesis. HMG-CoA reductase inhibitors lower the reactivity of arterial wall to vasoconstrictor agents, decrease the concentration of lipoprotein [a]--an independent risk factor of atherosclerosis, inhibit the generation of free radicals and lipid peroxidation, decrease the number of macrophages in atherosclerotic lesion and finally, equilibrate the clotting-fibrynolysis processes of attennuating platelets function, reducing the tissue factor synthesis and decreasing the concentration of plasminogen activator inhibitors. Statins are presently considered by NCEP to be the drugs of first choice for treatment of hypercholesterolemia.

[Treatment of hypertension in postmenopausal women]

Epidemiological and clinical studies have defined the lower incidence of atherosclerotic vascular disease in women than in age-matched men. After menopause the difference becomes less significant, what is due to estrogen deficiency. The mechanism of vascular protective effect of estrogen involves inhibition of smooth muscle cell proliferation, protection of endothelium function and improvement of lipid metabolism. One of the most important risk factor of atherosclerosis is hypertension. The prevalence of hypertension in elderly women is extremely high-up to 80%. Because of absence of the hormonal replacement therapy effect on blood pressure, there is an indication for antihypertensive therapy in postmenopausal women. Angiotensin-converting enzyme inhibitors are the class of drugs which can lower cardiovascular mortality due to hypertension and atherosclerosis in elderly women. They improve impaired insulin sensitivity and inhibit activation of renin-angiotensin system, both processes leading to the development of hypertension in postmenopausal women. Angiotensin-converting enzyme inhibitors also possess a direct anti-atherosclerotic properties, like inhibition of smooth muscle cell proliferation and migration, protection of endothelium function, reduced macrophages activation and foam cell accumulation, protection of LDL particles and improvement of fibrinolysis.

[The role of DNA polymorphism in the renin-angiotensin system and the pathogenesis of cardiovascular diseases]

Myocardial infarction and stroke are the major cause of death in developed countries and are the clinical manifestation of atherosclerosis and hypertension. Both the environmental factors and genetic predisposition have an influence on the pathogenesis of these diseases. Despite we know lots of environmental risk factors and we made important advances in the prevention and treatment of mentioned diseases, our knowledge about the pathogenic linkage between genetic predisposition and cardiovascular diseases is still very little. Activation of the renin-angiotensin system has been proposed as a very important step in the pathogenesis of hypertension and atherosclerosis. In spite of vasoconstrictor activity, angiotensin II can stimulate migration and proliferation of vascular smooth muscle cells, macrophage-foam cells formation, adhesion and aggregation of platelets and fibrinolytic system inhibition. Angiotensin convertin enzyme inhibitors reduce the development of the atherosclerotic process after vascular injury and in hyperlipidemic animals. Blockade of renin-angiotensin system seems to be also effective in secondary prevention of myocardial infarction in men. In sum, the genetic variations inside the renin-angiotensin system which may affect the function of its components might have an influence on genetic predisposition to cardiovascular diseases. The paper deals with the current state of knowledge on association between polymorphic variations in renin gene, angiotensinogen gene, angiotensin converting enzyme gene and AT1 receptor gene and primary hypertension, ischaemic heart disease and myocardial infarction.

[Anti-atherosclerotic action of hypotensive drugs]

Hypertension is an important risk factor for the development of atherosclerosis. Traditional antihypertensive therapy is not fully effective in prevention of cardiovascular abnormalities of hypertension. Two classes of hypotensive drugs, calcium antagonists and angiotensin-converting enzyme (ACE) inhibitors, reduce atherosclerosis in several experimental models in animals. Anti-atherosclerotic effects of calcium antagonists include attenuation of endothelial dysfunction, prevention of LDL modification, stimulation of LDL receptor activity, inhibition of superoxide radical generation and inhibition of vascular smooth muscle cells proliferation and migration. In large angiographic trials calcium antagonists reduced the development of new atherosclerotic plaques. ACE inhibitors also lead to the lower incidence of atherosclerosis in experimental animals. They inhibit migration and proliferation of vascular smooth muscle cells, reduce macrophage-derived foam cell accumulation, preserve protective endothelium function, reduce LDL modification and increase fibrinolytic activity. It depends on reduced angiotensin II synthesis, increased concentration of kinins, substance P and angiotensin-(1-7), inhibition of leukotriene B4 formation and improvement of insulin action. In some studies they also reduce plasma lipids concentration, including lipoprotein (a). ACE inhibitors were found to be ineffective in prevention of restenosis after PTCA in human but data derived from large, multicenter trials indicate that they are effective in the secondary prevention of myocardial infarction.

[Anti-atherosclerotic action of angiotensin converting enzyme II. Effect on metabolism of kinin, free radical reaction, sensitivity to insulin and lipid metabolism]

Blockade of the renin-angiotensin system reduces the development of the atherosclerotic process after vascular injury and in hyperlipidemic animals. ACE-inhibitors inhibit vascular smooth muscle cells migration and proliferation, macrophage-foam cell accumulation and preserve the antiaggregatory and antithrombotic function of the endothelium in atherosclerotic vessels. In addition to the inhibition of angiotensin II synthesis, reduced degradation of kinins and improvement of insulin action after ACE-inhibition may be responsible for observed actions. ACE-inhibitors may have also influence on lipids metabolism, including low density lipoprotein oxidation. Despite this, ACE-inhibitors failed to prevent restenosis after coronary angioplasty in humans. One reason for the lack of ACE-inhibitors effect in human restenosis might depend on the activation of the alternative angiotensin II-generating system in human arteries after vascular injury.

[Pharmacologic treatment of lipid metabolism disorders]

The aim of the treatment of dyslipidaemia is the primary and secondary prevention of coronary heart disease (CHD). Dietary therapy is the first line in the management of hyperlipidaemia. Lipid-lowering drugs should be used in patients with an inadequate dietary response, with CHD and/or multiple CHD risk factors. The choice of drug depends on the lipid disorder type, the desired plasma lipids reduction and presence of contraindications. Lipid-lowering drugs-anion-exchange resins, nicotinic acid and acipimox, fibrates, statins, probucol and two new classes used in experimental studies (ansamycins and ACAT inhibitors) are presented. Antiatherosclerotic properties of statins are characterized.

[Lipids and atherosclerosis]

Atherosclerosis is a degenerative pathology of blood vessels leading to coronary heart disease, myocardial infarction and stroke. The basic lesion of atherosclerosis is the fibrous plaque, which consists of lipids, smooth muscle cells, macrophages and connective tissue matrix. Data derived from experimental and clinical studies indicate the crucial role of elevated serum LDL-cholesterol concentration in the formation of atherosclerotic lesions. HDL removes cholesterol from the arterial wall, stimulates arterial prostacyclin synthesis, inhibits adhesion molecules expression, has antioxidant properties and protects against atherosclerosis. Lipoprotein (a) competes with plasminogen for its binding site, leading to reduced fibrinolysis and is an important link between thrombogenesis and atherosclerosis. The pathogenic role of lipids in atherogenesis is discussed.

The action of excessive, inorganic silicon (Si) on the mineral metabolism of calcium (Ca) and magnesium (Mg)

The influence of silicon treatment on the levels of calcium and magnesium in blood serum and tissues was studied in rats. The concentrations of both elements were estimated in samples of sera and tissues of rats receiving per os a soluble, inorganic silicon compound--sodium metasilicate nonahydrate (Na2SiO3.9H2O (REACHIM, USSR)), dissolved in the animals' drinking water. A decrease of magnesium concentration in serum was observed with accompanying elevation of registered calcemia. Moreover, a reduction of tissue calcium levels was found with a simultaneous increase of magnesium tissue pool. The results provide evidence for silicon involvement in mineral metabolism. It could result in a modification of pathological processes concerning bone tissue.

The influence of inorganic silicon (Si) on pituitary-thyroid axis

The influence of silicon-treatment on the levels of TSH and thyroid hormones was studied in rats. Concentrations of thyrotropin (TSH), triiodothyronine (T3), and thyroxine (T4) were estimated in sera of rats receiving per os a soluble silicon compound--sodium metasilicate nonahydrate (Na2SiO3.9H2O), dissolved in the animals' drinking water. An increase in the TSH level in the tested group was observed, without statistically significant differences in T3 and T4 concentrations between the two groups of animals. The results provide evidence for the influence of silicon on the endocrine balance. They could also prove that this chemical element is capable of modifying the rate of some hormones' synthesis.

Silicon metabolism. The interrelations of inorganic silicon (Si) with systemic iron (Fe), Zinc (Zn), and copper (Cu) pools in the rat

The influence of silicon treatment on the levels of trace elements zinc (Zn), copper (Cu), and iron (Fe) in serum and tissues was studied in rats. The concentrations of silicon, iron, and zinc were estimated in samples of sera and tissues of rats receiving per os a soluble, inorganic silicon compound--sodium metasilicate nonahydrate (Na2SiO3.9H2O), dissolved in the drinking water. An increase of copper concentrations in liver and aortic walls in the experimental group was observed, with simultaneous reduction of zinc amounts in serum and all the tissue samples in the course of the experiment. The iron concentrations in the analyzed samples did not show any significant changes between both groups. The silicon levels in serum and in all the examined tissues were significantly higher in the tested group. The results provide evidence for the silicon interaction with copper and zinc, which could result in a number of metabolic process modifications, antiatheromatous activity among them.

Anti-elastin antibodies in patients with lung cancer

The aim of this study was to investigate anti-elastin antibodies of the IgG and IgM types in sera of patients suffering from lung cancer, using the DOT immunobinding assay. We studied 96 pathological and 40 control sera. Anti-elastin antibodies were found to be present in 45% of patients with small cell lung cancer, 19% of subjects with adenocarcinoma and not-identified lung tumor and 15% of patients with squamous cell lung cancer. They circulated in 5% of control persons only. The highest values of their titers were observed in the advanced stages of disease. In 55% of anti-elastin antibody positive small cell lung cancer patients, antibodies were of the IgM type, suggesting the initial step of the autoimmunization to elastin.

Immunoglobulins and complement components levels in patients with lung cancer

Sera from 96 patients with lung cancer were assayed in order to evaluate the concentrations of IgG, IgA, IgM, C3c and C4. Histologically, 49 of the patients had squamous cell carcinoma, 11--adenocarcinoma, 20--small cell carcinoma and 16--not identified lung cancer. No statistically significant differences were found between the concentrations of IgG and IgM in patients with carcinoma of the lung versus subjects in the control group. Both serum IgA and complement components (C30 and C4) were significantly elevated in almost all patients from the tumor group as compared with the levels in the control group.

Evaluation of elastin metabolism in children from families with high risk of atherosclerosis

Markers of elastin metabolism were estimated in sera of children from families with a high risk of atherosclerosis (ATH). There was no statistically significant difference in the serum elastase-like activity between the groups studied. The concentration of elastin-derived peptides was statistically significantly elevated in the ATH group. Anti-elastin antibodies were found to be present in 73% of ATH children, while they circulated in 5% of control subjects only. Antibodies observed in the youngest ATH children were of the IgM type, suggesting the initial stage of the autoimmunization to elastin. The data obtained in this study may indicate an enhanced metabolism of elastin in ATH children.

Modulation of elastase-like activity in fibroblasts stimulated with elastin peptides

Elastin-derived peptides, kappa-elastin, prepared by chemical degradation of insoluble elastin from bovine ligamentum nuchae, were shown to increase the elastase-like activity in the culture medium and cell fractions in fibroblasts. Preincubation of cells with nifedipine (calcium channel blocker) and trifluoperazine (calmodulin antagonist) induced a decrease in the activities of the enzyme under study. These data suggest the possibility of pharmacological modulation of the biological effects induced by elastin-derived peptides.

Elastin and collagen content in the aorta of rabbits experimentally immunized with soluble elastin

Experimental immunization of rabbits with soluble porcine elastin was performed. A statistically significant decrease in the level of insoluble elastin in the aorta of the immunized animals was observed. Estimations of soluble collagen fractions showed the rise of both salt-soluble and acid-soluble collagen in the aorta of rabbits immunized with soluble porcine elastin.

Cross immunoreactivity of aortic kappa-2-elastin with some antibacterial antisera

Immunological and microbial factors may lead to the formation of atherosclerotic lesions. Cross immune reactions between aortic kappa-2-elastin and antisera against some antigens of Gram-negative bacteria--Salmonella and Escherichia coli--were studied using the dot-immunobinding assay. Positive results were obtained with antisera against Salmonella AO, BO, CO, EO, HM and Escherichia coli OK(A). Among immunological mechanisms leading to atherosclerosis cross immunoreactivity of aortic antigens with antimicrobial antibodies should be taken into consideration.

Succinyl trialanine p-nitroanilide hydrolytic activities in plasma and the aorta of rabbits experimentally immunized with soluble elastin

Experimental immunization of rabbits with soluble porcine elastin was performed. Elastase-like activities in plasma and the aorta were assayed using succinyl trialanine p-nitroanilide. A statistically significant increase in the elastase-like activity in plasma of the immunized animals was observed. Estimations of the elastase-like activity in the rabbit aorta showed the rise of analyzed parameters in the experimental group.

Pharmacological modulation of the antioxidant enzymes activities and the concentration of peroxidation products in fibroblasts stimulated with elastin peptides

1. Elastin peptides (kappa-elastin) prepared by alcoholic potassium hydroxide degradation of insoluble elastin were shown to increase the activities of antioxidant enzymes (SOD, CAT, GSH-Px) and the lipid peroxide concentration within fibroblasts. 2. The preincubation of cells with nifedipine (calcium channel antagonist) and trifluoperazine (calmodulin antagonist) caused the decrease in the activities of studied enzymes and the concentration of TBA-reactive products in fibroblasts stimulated with kappa-elastin. 3. The preincubation with ketotifen (antiallergic drug) has no effect on the activities of SOD, CAT, GSH-Px and the lipid peroxide concentration in stimulated cells. 4. These data suggest the possibilities of pharmacological modulation of the biological effects induced by elastin-derived peptides.

Blood histamine level in rabbits experimentally immunized with soluble elastin

Experimental immunization of rabbits with soluble porcine elastin was performed. An increase in histamine level in blood of immunized animals was observed.

[Anti-elastin antibodies in systemic lupus erythematosus]

Immunological response to elastin-derived peptides may cause tissue damage with subsequent degradation of the elastic fibres. Therefore, an incidence of anti-elastin antibodies in sera of patients with the systemic lupus erythematosus was studied. Sixty sera from 50 patients with systemic lupus erythematosus and 50 healthy subjects were assayed with dot-immunobinding technique. Titre 1:10 was considered diagnostically significant. Anti-elastin antibodies were diagnosed in 19 patients (31%) where as they were absent in the control group. In all cases anti-elastin antibodies were IgG.

[Tissue-type plasminogen activator--biochemistry, physiology and clinical use]

Tissue plasminogen activator (t-PA) is the main physiological activator of the fibrinolysis process present in nearly all organs, tissues and secretions. Its most important function is dissolving of intervascular fibrin deposits. T-PA is synthesized and secreted by the endothelium of blood vessels in response to various stimuli. Its enzymatic activity in plasma is controlled by rapidly acting inhibitors. Reduced generation of t-PA activity may be the cause of thrombotic changes in the vascular system. Studies are conducted presently on the use of t-PA in thrombolytic treatment.