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A Gvozdjáková

Publications and source records attributed to A Gvozdjáková.

At least 19 recordsLinked to original sources
PubMed2004

Regeneration of coenzyme Q9 redox state and inhibition of oxidative stress by Rooibos tea (Aspalathus linearis) administration in carbon tetrachloride liver damage.

The effect of rooibos tea (Aspalathus linearis) on liver antioxidant status and oxidative stress was investigated in rat model of carbon tetrachloride-induced liver damage. Synthetic antioxidant N-acetyl-L-cysteine (NAC) was used for comparison. Administration of carbon tetrachloride (CCl4) for 10 weeks decreased liver concentrations of reduced and oxidized forms of coenzyme Q9 (CoQ9H2 and CoQ9), reduced -tocopherol content and simultaneously increased the formation of malondialdehyde (MDA) as indicator of lipid peroxidation. Rooibos tea and NAC administered to CCl4-damaged rats restored liver concentrations of CoQ9H2 and alpha-tocopherol and inhibited the formation of MDA, all to the values comparable with healthy animals. Rooibos tea did not counteract the decrease in CoQ9, whereas NAC was able to do it. Improved regeneration of coenzyme Q9 redox state and inhibition of oxidative stress in CCl4-damaged livers may explain the beneficial effect of antioxidant therapy. Therefore, the consumption of rooibos tea as a rich source of natural antioxidants could be recommended as a market available, safe and effective hepatoprotector in patients with liver diseases.

Acetylcysteine↗
PubMed2002

Decreased levels of coenzyme Q(10) in patients with bronchial asthma.

BACKGROUND: The contribution of free oxygen radicals in the pathogenesis of bronchial asthma is generally accepted. The modulation of antioxidative defence by supplementation with antioxidants represents additive therapy in complex management of disease. The aim of the study was to assess the levels of coenzyme Q10, alpha-tocopherol, and beta-carotene both in plasma and whole blood, and malondialdehyde (MDA) and eosinophil cationic protein (ECP) in plasma of asthmatics (As). METHODS: Fifty-six As (15 males and 41 females) aged from 19 to 72 years (mean age 46 years) suffering from allergic asthma were enrolled into the study. The control group comprised 25 healthy volunteers (16 males, 9 females) aged 25-50 years. RESULTS: The concentrations of CoQ10 decreased significantly both in plasma and whole blood, compared with healthy volunteers (0.34 +/- 0.15 micromol/l vs. 0.52 +/- 0.15 micromol/l, 0.33 +/- 0.14 micromol/l vs. 0.50 +/- 0.13 micromol/l, P < 0.001, P< 0.001, respectively). The levels of alpha-tocopherol were decreased both in plasma and whole blood in comparison with controls [24.10 micromol/l (19.8; 30.5), vs. 33.20 micromol/l (28.25; 38.05), 17.22 +/- 6.45 micromol/l vs. 21.58 +/- 7.92 micromol/l, P= 0.006, P = 0.01, respectively]. The levels of MDA were elevated over the reference range in both groups (reference range < 4.5 micromol/l). No changes were seen in beta-carotene concentrations. Positive correlation was found between whole blood CoQ10 and alpha-tocopherol concentrations. CONCLUSION: Results of the study suggest a possible contribution of suboptimal concentrations of CoQ10 on antioxidative dysbalance in As and provide a rationale for its supplementation.

Adult↗
PubMed2001

[Effect of coenzyme Q10 in patients with kidney diseases].

BACKGROUND: Coenzyme Q10 belongs to important antioxidants and it has a key role in the synthesis of adenosinetriphosphate. Its beneficial effect was proved in several diseases, e.g. in mitochondrial encephalopathy, mitochondrial myopathy, mitochondrial cardiomyopathy. MATERIAL AND METHODS: All 15 patients of the studied group (5 with tubulopathy and 10 with chronic tubulointersticial nephritis) received antioxidative therapy for three months (E vitamin, C vitamin, riboflavin) and for the last two months coenzyme Q10 was added. Renal functions, spectrum of lipids, parameters of lipid peroxidation (malondialdehyde), levels of alpha-tocopherol, beta-carotene, coenzyme Q10. RESULTS: Before the substitutive antioxidative treatment, coenzyme Q10 levels reached in blood 0.11 +/- 0.03 mumol/l and 0.15 +/- 0.04 mumol/l in plasma. These values were well below the reference range (rr) is 0.4 +/- 1.0 mumol/l). After the substitution coenzyme Q10 levels significantly increased (p < 0.001) to the values of 1.66 +/- 0.16 mumol/l in blood and to 1.78 +/- 0.27 mumol/l in plasma. Plasma levels of beta-carotene increased from the markedly subnormal values 0.25 +/- 0.07 mumol/l (rr > 0.8 mumol/l) to 0.56 +/- 0.02 mumol/l (no statistical difference). Plasma levels of alpha-tocopherol remained within the reference range 32.15 +/- 4.73 mumol/l (rr 15-30 mumol/l) and they increased up to the plasma level of 44.83 +/- 5.82 mumol/l during the period of testing. Malondialdehyde levels did not significantly change within the testing period. No changes in renal functions and parameters of lipid metabolism were described. Patients well tolerated the treatment and no adverse effects were seen during the period of observation. CONCLUSIONS: Our results ascertained that levels of antioxidant CoQ10 were lower in patients with nephropathy who underwent conservative treatment with peroral substation. Such deficit can be amended by CoQ10 administration, which could be therefore taken as complementary treatment of nephrology.

Acidosis, Renal Tubular↗
PubMed2000

A study of creatine kinase reaction in rat brain under chronic pathological conditions-chronic ischemia and ethanol intoxication.

Creatine kinase reaction rates were measured by the magnetisation transfer technique in brains of healthy adult and aged rats and in rats with chronic cerebral ischemia and chronic ethanol intoxication. These measurements indicated that the rate constant of the creatine kinase reaction is significantly reduced in the case of severe chronic cerebral ischemia in aged rats. In the adult rats, during chronic ethanol intoxication after 3 weeks of administration of 3 ml of 30% ethanol once a day via a gastric tube, a significant decrease in the pseudo first-order rate constant k(for) of the creatine kinase reaction was also found. In contrast, mild chronic cerebral ischemia in adult rats produced an increase in the reaction rate 4 weeks after occlusion. At the same time, corresponding conventional phosphorus magnetic resonance spectra showed negligible changes in signal intensities.

Adenosine Triphosphate↗
PubMed2000

Metabolic changes in rat brain after prolonged ethanol consumption measured by 1H and 31P MRS experiments.

1. In vivo 1H and 31P magnetic resonance spectroscopy techniques were applied to reveal biochemical changes in the rat brain caused by prolonged ethanol consumption. 2. Three models of ethanol intoxication were used. 3. 1H MRS showed a significant decrease in the concentration of myo-inositol in the brain of rats fed with 20% ethanol for 8 weeks. This change is consistent with perturbances in astrocytes. On the other hand, N-acetyl aspartate and choline content did not differ from controls. 4. 31P MRS did not reveal any significant changes in the high-energy phosphates or intracellular free Mg2+ content in the brain of rats after 14 weeks of 20% ethanol drinking. The intracellular pH was diminished. 5. By means of a 31P saturation transfer technique, a significant decrease was observed for the pseudo first-order rate constant k(for) of the creatine kinase reaction in the brain of rats administered 30% ethanol for 3 weeks using a gastric tube. 6. The 1H MRS results may indicate that myo-inositol loss, reflecting a disorder in astrocytes, might be one of the first changes associated with alcoholism, which could be detected in the brain by means of in vivo 1H MRS. 7. The results from 31p MRS experiments suggest that alcoholism is associated with decreased brain energy metabolism. 8. 31P saturation transfer, which provides insight into the turnover of high-energy phosphates, could be a more suitable technique for studying the brain energetics in chronic pathological states than conventional 31P MRS.

Adenosine Triphosphate↗
PubMed2000

Passive smoking impairs endothelium-dependent relaxation of isolated rabbit arteries.

The aim of the present study was to examine the effect of prolonged passive smoking (lasting 3 weeks) on plasma catecholamine levels and reactivity of isolated rabbit arteries. Plasma noradrenaline, adrenaline and dopamine levels were determined radioenzymatically. Isolated rings of the thoracic aorta and carotid artery were suspended in organ chambers and connected to a force transducer for the recording of isometric tension. Plasma noradrenaline levels were found to be significantly elevated in rabbits subjected to passive smoking for 3 weeks. Plasma adrenaline and dopamine levels were not changed. Transmural nerve stimulation of arterial rings evoked frequency-dependent contractions. Prolonged passive smoking did not affect neurogenic contractions of the arteries tested. On the other hand, endothelium-dependent relaxations of phenylephrine-precontracted arteries were significantly impaired. Furthermore, hypertrophy of the left ventricle was observed. In conclusion, passive smoking impairs endothelium-dependent relaxations but not neurogenic contractions of systemic arteries. The impaired relaxations of arteries may be, at least in part, mediated through the degradation of released nitric oxide by superoxide anions derived from cigarette smoke.

Animals↗
PubMed2000

Deficit of coenzyme Q in heart and liver mitochondria of rats with streptozotocin-induced diabetes.

Mitochondrial dysfunction and oxidative stress participate in the development of diabetic complications, however, the mechanisms of their origin are not entirely clear. Coenzyme Q has an important function in mitochondrial bioenergetics and is also a powerful antioxidant. Coenzyme Q (CoQ) regenerates alpha-tocopherol to its active form and prevents atherogenesis by protecting low-density lipoproteins against oxidation. The aim of this study was to ascertain whether the experimentally induced diabetes mellitus is associated with changes in the content of endogenous antioxidants (alpha-tocopherol, coenzymes Q9 and Q10) and in the intensity of lipoperoxidation. These biochemical parameters were investigated in the blood and in the isolated heart and liver mitochondria. Diabetes was induced in male Wistar rats by a single intravenous injection of streptozotocin (45 mg x kg(-1)), insulin was administered once a day for 8 weeks (6 U x kg(-1)). The concentrations of glucose, cholesterol, alpha-tocopherol and CoQ homologues in the blood of the diabetic rats were increased. The CoQ9/cholesterol ratio was reduced. In heart and liver mitochondria of the diabetic rats we found an increased concentration of alpha-tocopherol, however, the concentrations of CoQ9 and CoQ10 were decreased. The formation of malondialdehyde was enhanced in the plasma and heart mitochondria. The results have demonstrated that experimental diabetes is associated with increased lipoperoxidation, in spite of the increased blood concentrations of antioxidants alpha-tocopherol and CoQ. These changes may be associated with disturbances of lipid metabolism in diabetic rats. An important finding is that heart and liver mitochondria from the diabetic rats contain less CoQ9 and CoQ10 in comparison with the controls. We suppose that the deficit of coenzyme Q can participate in disturbances of mitochondrial energy metabolism of diabetic animals.

Animals↗
PubMed1999

Coenzyme Q10 depletion and mitochondrial energy disturbances in rejection development in patients after heart transplantation.

UNLABELLED: Sixty endomyocardial biopsies (EMB) and whole blood or plasma samples from 34 patients after heart transplantation (HTx-pts) were studied. Acute rejection of the transplanted heart was histologically graded as: 0 (without), 0-1 (incipient), 1 (mild), 2 (moderate). The level of coenzyme Q10 (CoQ10) in 28 EMB was estimated by HPLC. Mitochondrial respiratory chain function and energy production were measured in 60 EMB. This study is the first report showing a correlation between: (a) histological signs of rejection in the human transplanted heart and (b) CoQ10 level of EMB, CoQ10 blood level, and mitochondrial bioenergetic processes: inhibition in FAD-part, but not in NAD-part of respiratory chain. In all patients after heart transplantation (HTx-pts) the dynamic balance between total antioxidant status and degree of oxidative stress was disturbed. CONCLUSIONS: CoQ10 level and mitochondrial bioenergetic functions of EMB contribute to the explanation of pathobiochemical mechanisms of origin and development rejection of human transplanted heart. We suppose that estimation of EMB CoQ10 level could be used as a bioenergetic marker of rejection development in human transplanted heart. CoQ10 therapy could contribute to the prevention of rejection of the transplanted heart.

Antioxidants↗
PubMed1999

Captopril increased mitochondrial coenzyme Q10 level, improved respiratory chain function and energy production in the left ventricle in rabbits with smoke mitochondrial cardiomyopathy.

The aim of the study was to show whether the ACE inhibitor captopril is able to protect the heart against the deleterious effect of passive cigarette smoking on left ventricular mitochondria. Four groups of rabbits were investigated: control (C), passive smoking of three cigarettes twice daily/30 minutes (S), control + captopril (7.5 mg/kg body weight twice daily) (Cap), and smoking + captopril (SCap) as in group 2 and 3. Three weeks lasting passive smoking impaired oxidative phosphorylation, diminished cytochrome oxidase activity and increased the mitochondrial F1-ATPase protein concentration. Moreover, the level of coenzyme Q10 (CoQ10) and coenzyme Q9 were decreased. Simultaneous treatment with captopril prevented partly the decrease of CoQ10 level, deterioration of oxidative phosphorylation, diminution of cytochrome oxidase activity and enhancement of F1-ATPase level. We conclude that captopril protected the myocardium against the harmful effect of passive smoking in rabbits.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1999

[The effect of streptozotocin-induced diabetes in the neonatal period on hepatic mitochondrial bioenergetics in adult rats].

BACKGROUND: Previous experimental studies focused on the liver mitochondrial bioenergetic changes in diabetes mellitus type I induced in adult animals. Information about the effects of persisting neonataly induced diabetes mellitus type I on the mitochondrial bioenergetics are missing. AIM: The aim of the study was to assess the degree of diabetes mellitus compensation and parameters of oxidative phosphorylation in rats aged 3 months with DM persisting from neonatal period. METHODS: DM was induced in male Wistar rats by repeated intraperitoneal administration of streptozotocine 45 mg/kg on 2nd and 9th day after birth. The concentrations of glucose, glycosylated haemoglobin, fructosamine were detected in the blood and the concentration of cholesterol and triacylglycerols in the blood and liver tissue, respectively. After mitochondria isolation from the liver we measured parameters of oxidative phosphorylation by polarography using Clark oxygen electrode. RESULTS: In the group of neonataly induced DM the concentration of glucose (23.10 +/- 1.55 vs 8.3 +/- 0.56 mmol/l), glycosylated haemoglobin (6.04 +/- 1.17 vs 3.99 +/- 0.44%) and blood cholesterol concentration (2.15 +/- 0.11 vs 1.83 +/- 0.09 mmol/l) increased significantly (p < 0.001 and p < 0.005 for cholesterol) comparing to a group of healthy rats. No statistically significant differences were found in the remaining parameters when comparing these two groups. The parameters of oxidative phosphorylation were significantly (p < 0.001) decreased in the group with DM comparing to control group of healthy animals--the index of respiratory control (4.87 +/- 0.25 vs 9.57 +/- 0.34), the rate of oxygen consumption in the stage 3 in ADP presence (88.61 +/- 4.62 vs 165.08 +/- 4.5 natO.mg/protein/min) and phosphorylation rate (203.54 +/- 7.26 vs 332.87 +/- 7.39 nmolATP.mg/protein/min) with NAD substrate glutamate. Similar trend was also seen with FAD substrate succinate. The index of oxidative phosphorylation ADP:0 was not changed in both groups. CONCLUSIONS: In 3 months old rats with neonataly induced DM the development of steatosis was not observed and uncoupling of oxidative processes from phosphorylation did not appear. Energy production was sufficient enough for normal functions of the liver and to ensure all needs of the organism. (Tab. 4, Ref. 51.)

Aging↗
PubMed1998

Participation of coenzyme Q10 in the rejection development of the transplanted heart: a clinical study.

Coenzyme Q10 and alpha-tocopherol concentrations were assessed in 28 endomyocardial biopsies from 22 patients and in 61 blood samples from 31 patients after heart transplantation with histologically confirmed signs of rejection. The values were compared to the group of 14 patients with cardiomyopathies of unclear etiology as candidates for heart transplantation. Blood analyses were also compared with 50 healthy persons. Myocardial and blood coenzyme Q10 concentrations were already significantly decreased in the incipient phase of rejection (degree 0-1) and also in rejection phase 1 and 2. In patients without rejection signs myocardial and blood coenzyme Q10 values were similar to those of cardiomyopathic patients. No significant differences were found in alpha-tocopherol concentrations in relation to signs of rejection. Increased plasma lipid peroxidation quantified as malondialdehyde production was detected in all groups of transplanted patients. The results contribute to the explanation of some pathobiochemical mechanisms participating in the rejection development of the transplanted heart.

Adult↗
PubMed1998

[Inhibition of lipid peroxidation in erythrocytes by aminoguanidine, resorcylidine aminoguanidine and their oxygen and sulfur analogs in diabetic rats].

This study examined the effect of aminoguanidine (AG) and its structural analogs semicarbazide (SK) and thiosemicarbazide (TSK), as well as their condensation products with 2,4-dihydroxybenzaldehyde-resorcylidene aminoguanidine (RAG), resorcylidene thiosemicarbazone (RTSKon), and resorcylidene semicarbazone (RSKon) on erythrocyte lipid peroxidation in rats with diabetes mellitus induced by hydrogen peroxide. All of the tested compounds at concentrations 1 mmol.l-1 in incubation mixture significantly inhibited the formation of malondialdehyde (MDA), an end product of lipid peroxidation, as assessed by its thiobarbituric acid reactivity. AG and RAG were the most effective inhibitors of lipid peroxidation 90%). It was also found, that RSKon and RTSKon were more potent inhibitors of lipid peroxidation (70 and 80%) compared to Sk and TSK (50%). We suppose that this increase of inhibitory effect by compounds with resorcylidene group may be due to the formation of quinone structure.

Animals↗
PubMed1997

Effect of captopril on the development of left ventricular hypertrophy in rabbits with aortic insufficiency.

We investigated the effect of captopril on the growth of the left ventricle in an experimental model of aortic insufficiency. Four groups of rabbits were studied 28 days after experimental intervention: 1. control, 2. control with captopril (10 mg/kg/day), 3. aortic insufficiency, 4. aortic insufficiency with captopril (10 mg/kg/day). Aortic insufficiency induced hypertrophic growth of the left ventricle demonstrated by increased weight and ribonucleic acid (RNA) concentration. Administration of captopril only slightly attenuated the weight increase of the left ventricle and the increase in concentration of left ventricular RNA. However, captopril reduced the concentration of left ventricular deoxyribonucleic acid (DNA) both in the control and even more in the group with aortic insufficiency. The chronic haemodynamic overload enhanced mitochondrial respiration in the left ventricle which was not influenced by captopril. We conclude that captopril in the dose 10 mg/kg/day did not prevent hypertrophy of the left ventricle but reduced left ventricular DNA concentration.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1996

[Cardiomyopathies from the aspect of clinical and experimental cardiology].

The study represents a summary of the latest experience, definitions, classification and diagnostics in cardiomyopathologic diseases. The main attention is drawn to the pathogenesis of cardiomyopathies, especially regarding the metabolic disturbances of the cardiac muscle on the mitochondrial level: the disturbances of oxidative and related energetic processes which the authors have registered in coincidence with the cardiomyopathological alcohol and smoking experimental model. The conclusion includes a notice about the prospective possibility for human cardiology to study these metabolic disturbances in endomyocardial biopsies in order to assess the diagnosis in early thus still reversible stages.

Cardiomyopathies↗
PubMed1996

[Cardiopathies of unknown origin--a cooperative interdisciplinary study].

The authors described aim. objectives, design and criteria of the study which is oriented to the clinical and research problems of heart diseases of uncertain origin. The paper presents the preliminary experience with invasive cardiological techniques in this field. At the same time the authors discuss the potential impact of the basic research on the prevention and effective treatment of cardiopathy which is until now of unknown origin.

Adolescent↗
PubMed1996

[Metabolic study of mitochondria in myocardial biopsies in patients with cardiopathy of unknown origin].

BACKGROUND: Mitochondrial cardiomyopathies are being studied as metabolic diseases of the cardiac muscle which represents a new approach in metabolic studies. The development of mitochondrial diseases is concomited by an impairment in complexes of mitochondrial respiratory chain, which so far could have been possibly studied exclusively on experimental animals. The method of skinned? fibers enables to measure the pathobiochemical processes in mitochondria in a small amount of bioptic myocardial tissue of patients. AIM: The study is aimed at: applying the method of skinned fibers in biopsy of myocardium in patients, trying to localize the impaired loci of the mitochondrial respiratory chains, prospective early and fast assessment of the diagnosis of mitochondrial cardiomyopathy in patients. CONCLUSIONS: The study brings the first information on the possibility of performing more value measurements of mitochondrial respiratory chains per one bioptic sample from the myocardium in patients. The preliminary results indicate to the prospective possibility of early and fast assessment of the diagnosis of mitochondrial cardio(myo)pathies. The presented results require complementary studies involving the development of "mitochondrial medicine".

Biopsy↗
PubMed1996

[Determination of coenzyme Q10 and alpha-tocopherol levels in patients with cardiopathies of unknown origin: perspectives in diagnosis].

The coenzyme Q10 (ubiquinone) plays an important role in bioenergetic conditions in myocardiac cells and together with alpha-tocopherol they act as endogenous antioxidants. Decreased levels in coenzyme Q10 were confirmed in some types of cardiomyopathies and in failing myocardium. Insufficiency of E vitamin is a risk factor in cardiovascular diseases. The study investigates the levels of coenzyme Q10 and alpha-tocopherol in the blood and in bioptic samples of the myocardium in patients with cardiopathies of unknown origin and it is aimed at their application as an auxiliary diagnostic method. The authors have introduced a method of coenzyme Q10 and alpha-tocopherol assessment from the bioptic samples of the myocardium, from the blood and plasma of these patients by means of high-performance liquid chromatography (HPLC). The authors detected decreased levels of coenzyme Q10 in the myocardium and blood of patients with cardiopathies. The dependence on the functional state of the myocardium according to NYHA was not confirmed due to the small number of patients. The plasmatic alpha-tocopherol levels decreased in dependence on the severeness of the disease. A more significant dependence was detected between the levels of alpha-tocopherol in the myocardium and its functional state. The average myocardial level of alpha-tocopherol in patients of the NYHA II group was almost ten-fold higher than in the NYHA II group. The gained results appoint to the meaning of investigation of the coenzyme Q10 and alpha-tocopherol in patients with cardiopathies of unknown origin and give a hint of prospective possibilities for application in the diagnosis assessment.

Cardiomyopathies↗