Effects of coenzyme Q10 supplementation on activities of selected antioxidative enzymes and lipid peroxidation in hypertensive patients treated with indapamide. A pilot study.

INTRODUCTION: An increase in oxidative stress is strongly documented in hypertensive patients. In blood vessels, oxidative stress increases the production of superoxide anion (O(2) (•-)) that reacts with nitric oxide (NO) and impairs the ability of endothelium to relax. Many reports indicate a beneficial effect of coenzyme Q10 (CoQ) in hypertension. Coenzyme Q10 therapy may lower O(2) (•-) and thus decrease the complications associated with hypertension. The aim of our study was to evaluate the effects of CoQ supplementation on antioxidative enzyme activities and lipid peroxidation in elderly hypertensive patients. MATERIAL AND METHODS: We determined the activities of superoxide dismutase (SOD-1) and glutathione peroxidase (GSH-Px) and the concentration of malondialdehyde (MDA) in erythrocytes of 27 elderly (mean age 72.5 ±6.1 year) hypertensive patients treated with indapamide at baseline and after 12 weeks of CoQ supplementation (60 mg twice a day) in comparison with 30 healthy elderly volunteers (mean age 76.8 ±8.5 year). RESULTS: Decrease of SOD-1 (p < 0.001) and insignificant reduction of GSH-Px activities and increase of MDA (p < 0.001) level were observed in hypertensive patients in comparison to healthy volunteers before supplementation. Coenzyme Q10 administration resulted in a significant increase only in SOD-1 activity (p < 0.001). CONCLUSIONS: The present study indicates that CoQ improves the most important component of the antioxidant defence system - SOD-1, which is responsible for O(2) (•-) scavenging. Coenzyme Q10 may be used as an additional therapeutic agent for prophylaxis and treatment of hypertension in elderly patients.

Evaluation of selected parameters of the antioxidative system in patients with type 2 diabetes in different periods of metabolic compensation.

INTRODUCTION: The aim of the study was to evaluate some selected parameters of the antioxidative system in patients with type 2 diabetes. MATERIALS AND METHODS: Eighty-one type 2 diabetes patients took part in the study (39 patients with metabolically balanced and 42 with metabolically unbalanced diabetes). The control group consisted of 30 healthy people. The total antioxidant capacity of plasma was measured fluorometrically using phycoerythrin. To calculate the low-molecular-weight antioxidant concentration in the plasma samples, the duration of Trolox activity as a function of its concentration in the sample was measured. The activity of antioxidative enzymes in red blood cells was determined using the Misra and Fridovich method and Beers and Sizer method. RESULTS: The total plasma antioxidant capacity and the low-molecular-weight antioxidant concentration in the group of patients with metabolically compensated type 2 diabetes were statistically significantly higher than in the group of patients with metabolically uncontrolled diabetes. The activity of antioxidative enzymes was found to be higher in the group of type 2 diabetes patients at the stage of metabolic balance. CONCLUSIONS: The obtained results confirm the thesis of glucose toxicity and intensification of oxidative stress in patients with diabetes.

[Evaluation of some selected structural and functional parameters of red blood cells as oxidative stress markers in elderly people with primary hypertension]. / Ocena wybranych parametrów strukturalnych i czynnosciowych krwinek czerwonych jako markerów stresu oksydacyjnego u osób w z pierwotnym nadcisnieniem tetniczym w podeszlym wieku.

UNLABELLED: The aim of the study was to evaluate the degree of membrane lipid peroxidation, internal microviscosity, activity of both total and Na+, K+ membrane ATP-ase and markers of oxidative damage of membrane protein in erythrocytes of elderly people with primary hypertension. MATERIAL AND METHODS: The examination was performed on 50 people. The first group (HA) consisted of 15 elderly people with primary hypertension (mean age 71, 3 years old). The reference groups were formed with healthy elderly people (K1) (15 people, mean age 72, 4 years old) and younger healthy people (K2) (20 people, mean age 55, 3 years old). RESULTS: Membrane lipid peroxidation of red blood cells was significantly increased in the group of elderly people with primary hypertension (HA). The lowest level of lipid peroxidation was observed in the (K2) normotensive group of younger people. Erythrocyte internal microviscosity was significantly higher in the group of healthy elderly people (K1) compared with the group of healthy younger people (K2). In HA group additional essential increase in microviscosity was observed in comparison with K1 and K2. The activity of both total and Na+, K+ membrane ATP-ase was significantly the highest in the group of younger people and the lowest in the group of elderly people with primary hypertension. In HA group increased damage of membrane protein was observed that was indicated by the reduced -SH group content and the increased value of W/S parameter in comparison with K1 and K2 groups. CONCLUSIONS: The obtained results indicate that in the elderly people with accompanying primary hypertension the whole-body oxidative stress is increased, which may be indicated by structural and functional oxidative damage of red blood cells. These observations may be significant in the pathogenesis of hypertension complications. This observation may be important in the pathogenesis of hypertension complications in this period of life.

[Anti-inflammatory action of myoinositol in renal insufficiency]. / Przeciwzapalne dzialanie mioinozytolu w przewleklej niewydolnosci nerek.

AIM OF THE STUDY: Release of prostaglandin E2 (PGE2) and leukotrien B4 (LTB4) in vitro by resting and PHA-stimulated peripheral blood mononuclear cells (PBMNC) in the presence of three concentrations of myoinositol (30, 300, 600 micromol/l) was investigated. MATERIAL AND METHODS: We examinated 10 uremic patients on regular hemodialysis treatment and 10 healthy subjects (control group). RESULTS: Release of PGE2 and LTB4 by resting and PHA-stimulated PBMNC was significantly lower in the presence of myoinositol in concentrations generally obserwed in the blood serum of chronic uraemic patients on regular hemodialysis treatment (600 micromol/l) in both investigated groups, while it remained unchanged in the presence of myoinositol in the concentration observed in normal blood serum (30 micromol/l). CONCLUSION: The results seem to indicate that myoinositol, in the concentrations found in uremic blood serum, may possibly exert antiinflammatory actions.

[The influence of Q10 coenzyme on structural and functional parameters of red blood cells in elderly people]. / Wplyw suplementacji koenzymu Q10 na wybrane parametry strukturalne i czynnosciowe krwinki czerwonej u osób w podeszlym wieku.

UNLABELLED: The free radical theory of aging assumes that aging process leads to lost of oxidative balance. Oxidative stress induces structural and functional changes in red blood cell. The Q10 coenzyme is known as a compound which may partially prevent those changes in erythrocytes, due to its antioxidative properties and the important role it plays in the cell. The content of the coenzyme in human body decreases with age. The aim of the research was to evaluate the degree of membrane lipid peroxidation, internal microviscosity, activity of membrane ATP-ase and oxidative damage markers of erythrocyte membrane protein in elderly people before and after Q10 coenzyme therapy. MATERIAL AND METHODS: The examination was performed on 35 people. The examined group consisted of elderly people (older than 65 years old). The reference group was formed with people at the age between 51 and 59. In both groups the initial parameters of red blood cells were evaluated. In the elderly people the investigated parameters were also controlled after three and six weeks of Q10 coenzyme intake. RESULTS: The Q10 coenzyme supplementation in elderly people produced the increase in the -SH group contents and reduction of W/S parameter. After supplementation of Q 10 coenzyme the decrease of lipid peroxidation products and internal microviscosity of erythrocytes and increase of the activity of membrane ATP-ase (total and Na+,K+) were observed. CONCLUSION: The obtained results may indicate the intensification of oxidative stress in elderly and point to beneficial effect of supplementation-metabolic therapy with Q10 coenzyme on structural and functional parameters of red blood cells in elderly people.

[The total antioxidant capacity and low-molecular antioxidant concentration in plasma of type-2 diabetes patients with different stage of metabolic compensation and concomitant diabetic nephropathy]. / Calkowita zdolnosc antyoksydacyjna oraz stezenie antyoksydantów drobnoczasteczkowych w osoczu u chorych na cukrzyce typu 2. w róznym okresie wyrównania metabolicznego oraz z towarzyszaca nefropatia cukrzycowa.

UNLABELLED: The experimental and clinical researches suggest important role of advanced glycation end products (AGE) and oxidative stress in pathogenesis of diabetic angiopathy also including nephropathy. It is especially pointed at by the research done on inadequately controlled long-term diabetes. The aim of the study was to asses the total antioxidant capacity of plasma as well as the concentration of low-molecular antioxidants in plasma in diabetes type 2 patients in different stage of metabolic compensation and concomitant diabetic nephropathy. MATERIAL AND METHODS: 91 diabetes type 2 patients took part in the research (31 patients with metabolic compensated diabetes, 14 patients with metabolically decompensated diabetes, 14 patients with incipient and 16 patients with overt nephropathy). The control group consisted of 40 healthy men. The total antioxidant capacity was fluorometrically marked by means of ficoerythryne. The concentration of low-molecular antioxidants in plasma was marked on the basis of the time of free radicals scavenging by means of Trolox (6-hydroxy-2, 5,7, 8-tetramethethylchroman-2-carboxylic acid) of known concentration. RESULTS: In patients with diabetes type 2 the total biggest antioxidant capacity was noted in metabolically compensated diabetes group and the total lowest antioxidant capacity was noted in diabetic patients with overt nephropathy. The highest mean concentration of low-molecular antioxidants was noted in metabolically compensated diabetes group and the lowest in diabetic patients with overt nephropathy. These differences were statistically significant. CONCLUSION: In patients with diabetic nephropathy with the development of the disease significant insufficiency of plasma antioxidant barrier is noted. Diminishing of the total antioxidant capacity and depletion of plasma antioxidants noted in diabetes type 2 patients, especially inadequately metabolically controlled may constitute the essential pathogenetic factor of vascular complication in diabetes.

[Evaluation of oxidative stress parameters in diabetes 2 patients in different stage of metabolic compensation]. / Ocena wybranych parametrów stresu oksydacyjnego u chorych na cukrzyce typu 2 wyrównanq i niewyrównana metabolicznie.

Etiopathogenesis of vascular complications in diabetes is complex and multifactorial. One of the factors that is connected both with chronic complications of diabetes and intensification of oxidative stress is long-term hyperglicaemia. It has been noted that control improvement of glicaemia delays and/or inhibits the development of further complications. The aim of the study was to evaluate selected parameters of oxidative stress in patients with metabolic compensated or decompensated diabetes by means of marking in red blood cells of the patients in question the activity of antioaxidative enzymes such as: superoxide dysmutase (SOD-1) and catalase (CAT) and concentration of malondialdehyde (MDA). 61 diabetic patients took part in the research, 31 of which met the criteria of metabolic compensation whereas 30 were metabolically decompensated. The reference group (K) consisted of 40 healthy men. The activity of SOD-1 was marked by Misra and Fridovich's method, the activity of CAT by Beers and Sizer's method and the concentration of MDA in red blood cells was indicated by Placer et al. The activity of evaluated antioxidative enzymes SOD-1 and CAT in the erythrocytes of diabetes type 2 patients was statistically lower as compared with the control group. The highest activity of SOD-1 and CAT was noted in metabolic decompensated diabetes type 2 group. The concentration of MDA in diabetes type 2 patients red blood cells was significantly higher as compared with the control group. Significantly higher concentration of MDA was noted in metabolically decompensated diabetic patients comparing to patients with proper metabolically compensated diabetes. The obtained results confirm the toxicity of glucose. Long-term hyperglicaemia through activation of different metabolic paths leads to the intensification of free radical processes and attenuation of antioxidative mechanisms.

[Blood serum and neutrophil amino acid concentrations during hemodialysis]. / Stezenia aminokwasów w osoczu i granulocytach obojetnochlonnych u pacjentów przewlekle dializowanych.

The abnormal amino acid profile and altered distribution of some amino acids between the extra- and intracellular compartments is currently recognized as a part of metabolism abnormalities in hemodialyzed uremic patients associated with prognosis. The aim of this study was to investigate the pattern of HD influence on the extra- and intracellular amino acid concentrations in neutrophil homogenates and in blood serum. Before HD, the concentrations of arginine (64 vs 33 micromol/l) and cysteine (70 vs 40 micromol/l) were significantly higher in the uremic blood serum, but the concentrations of five amino acids, i.e. serine, threonine, alanine, proline, and valine, were significantly decreased in the uremic serum. The concentrations of arginine (7.95 vs 5.2 micromol/l), tyrosine (14.3 vs 12.5 micromol/l) and phenylalanine (10.7 vs 9.5 micromol/l) were significantly elevated in neutrophil homogenate from uremic patients before HD and after HD for arginine (8.73 micromol/l). We found a substantial increase of blood serum arginine concentration at all evaluated time points of HD from 64 to 191 micromol/l. The concentration of 8 amino acids were found to be significantly decreased in blood serum during HD. We may assume amino acid concentration changes in chronic uremia partly attributed to malnutrition, may be actually associated with inflammatory pathomechanisms, the hypothesis worth verifying in further studies.

[The role of metalloproteinases in kidney pathophysiology]. / Rola metaloproteinaz w patofizjologii nerek.

Disturbances in extracellular matrix changes underlie many diseases. Metalloproteinases (MMP) are thought to play a very important role in the maintenance of proper balance between degradation and regeneration of tissue basic substance. MMP is a group of enzymes capable of digesting almost all extracellular matrix (ECM) components. Extracellular matrix of the tissues not only constitutes the support for its cells but also participates in cell metabolism regulation. Any disturbance in the balance between matrix degradation and regeneration is the clue to pathophysiology of many diseases. Metalloproteinases of ECM are a big family of zinc-dependent enzymes that include, among others, interstitial collagenases, matrix lysines, gelatinases, elastases and membrane-type matrix metalloproteinases (MT-MMP). Studies performed in animal models with MMP deficiency that have been carried out in the last few years have supplied a unique tool for the analysis of the role of gelatinase in physiological and pathophysiological development processes. However, the studies have proved complexity of the problem revealing not only protective but also destructive role of MMP depending on the experimental animal model which leaves a wide area for further investigations not only in animals but also patients with chronic kidney diseases. In the later part of our study we would like to focus on previous results of studies and views on the influence of MMP on kidney pathophysiology on the basis of available literature.

[Effects of hemodialysis with different membranes on blood serum nitrite/nitrate concentrations]. / Wplyw zabiegu hemodializy z uzyciem róznych blon dializacyjnych na stezenia azotynów/azotanów w surowicy krwi.

Blood serum nitrite/nitrate concentrations were determined in 10 patients with chronic uraemia during 4-hour hemodialysis (HD). Cuprophane, polysulphone and polyacrylnitrile dialysis membranes were used during HD procedures. Blood serum concentrations of nitrite/nitrate were increased in HD patients prior to hemodialysis as compared with respective values in healthy subjects. During hemodialysis, regardless of the membrane type used, blood serum nitrite/nitrate concentrations were progressively decreasing as compared with initial values found before hemodialysis. The lowest decrease of blood serum nitrite/nitrate concentrations was found during HD with cuprophane membrane.