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2. Endogenous protective mechanisms in remodeling of rat heart mitochondrial membranes in the acute phase of streptozotocin-induced diabetes
- Creator:
- Miroslav Ferko, Dana Kincelová, Waczulíková, I., Jana Mujkošová, Jarmila Kucharská, Šikurová, L., Ziegelhöffer, B., Ján Styk, and Atila Ziegelhöffer
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Experimentální medicína, kardiovaskulární fyziologie, mitochondrie, srdce, potkan, cardiovascular physiology, mitochondrias, heart, Rattus norvegicus, diabetic rat, oxidative phosphorylation, mitochondrial membrane fluidity, mitochondrial transmembrane potential, 14, and 616-092
- Language:
- English
- Description:
- The aim of present study was to investigate functional and physical alterations in membranes of heart mitochondria that are associated with remodeling of these organelles in acute phase of streptozotocin-induced diabetes and to elucidate the role of these changes in adaptation of the heart to acute streptozotocin-induced diabetes (evaluated 8 days after single dose streptozotocin application to male Wistar rats). Action of free radicals on the respiratory chain of diabetic-heart mitochondria was manifested by 17 % increase (p<0.05) in oxidized form of the coenzyme Q10 and resulted in a decrease of states S3 and S4 respiration, the respiratory control index, rate of phosphorylation (all p<0.01) and the mitochondrial transmembrane potential (p<0.05), but the ADP/O ratio decreased only moderately (p>0.05). On the contrary, membrane fluidity and the total mitochondrial Mg2+-ATPase activity increased (both p<0.05). In diabetic heart mitochondria, linear regression analysis revealed a reciprocal relationship between the increase in membrane fluidity and decrease in trans-membrane potential (p<0.05, r = 0.67). Changes in membrane fluidity, transmembrane potential, Mg2+-ATPase activity and the almost preserved ADP/O ratio appear as the manifestation of endogenous protective mechanisms participating in the functional remodeling of mitochondria which contributes to adaptation of the heart to diabetes., M. Ferko, D. Habodászová, I. Waczulíková, J. Mujkošová, J. Kucharská, L. Šikurová, B. Ziegelhöffer, J. Styk, A. Ziegelhöffer., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Involvement of membrane fluidity in endogenous protective processes running on subcellular membrane systems of the rat heart
- Creator:
- Atila Ziegelhöffer, Waczulíková, I., Miroslav Ferko, Šikurová, L., Mujkošová, J., and Ravingerová, T.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, rat heart sarcolemma, mitochondria, membrane fluidity, diabetes, hypertension, endogenous protection, 14, and 612
- Language:
- English
- Description:
- Membrane fluidity is a widely recognized biophysical variable that provides information about structural organization of the subcellular membranes exhibiting physical characteristics of liquid crystals. The term “fluidity” reflects in this case the tightness in packing of acyl parts of the membrane phospholipid molecules, a feature that may influence considerably the molecular mobility and via that also the sensitivity and reactivity of membranebound transporters, receptors and enzyme systems. Data presented in this review are aimed to demonstrate the substantial role of changes in membrane fluidity occurring in the processes associated with endogenous protection observed in cardiac sarcolemma and mitochondria in diverse pathologies, particularly in diabetes and hypertension., A. Ziegelhöffer, ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Liver mitochondrial respiratory function and coenzyme Q content in rats on a hypercholesterolemic diet treated with atorvastatin
- Creator:
- Oľga Uličná, Vančová, O., Waczulíková, I., Peter Božek, Šikurová, L., Viliam Bada, and Jarmila Kucharská
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, hypercholesterolemia, atorvastatin, liver mitochondria, oxidative phosphorylation, coenzyme Q, 14, and 612
- Language:
- English
- Description:
- Statins, inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, are effective drugs in the treatment of hypercholesterolemia, however, their undesirable actions are not fully known. We investigated the effects of atorvastatin on the oxidative phosphorylation and membrane fluidity in liver mitochondria, and also on the coenzyme Q (CoQ) content in the mitochondria, liver tissue, and plasma of rats on a standard (C) and hypercholesterolemic (HCh) diet. Atorvastatin was administered at either low (10 mg⋅kg-1) or high dose (80 mg⋅kg-1) for four weeks. The high dose of the drug decreased the concentrations of total cholesterol and triacylglycerols in the plasma and liver of rats on a HCh diet. Administration of atorvastatin was associated with decreased oxygen uptake (state 3), and oxidative phosphorylation rate in the mitochondria of both C and HCh rats. Further, the drug influenced mitochondrial membrane fluidity and dose-dependently reduced concentrations of oxidized and reduced forms of CoQ in the mitochondria. Our findings point to an association between in vivo administration of atorvastatin and impaired bioenergetics in the liver mitochondria of rats, regardless of diet, in conjunction with simultaneous depletion of oxidized and reduced CoQ forms from the mitochondria. This fact may play a significant role in the development of statin-induced hepatopathy., O. Uličná ...[et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. The effect of vitamin D3 supplementation on intracellular calcium and plasma membrane calcium ATPase activity in early stages of chronic kidney disease
- Creator:
- Morvová, M., Ingrid Lajdová, Viera Spustová, Zvarík, M., and Šikurová, L.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, vápník, vitamin D, calcium, calcium-ATPase, chronic kidney disease, vitamin D3, 14, and 612
- Language:
- English
- Description:
- Chronic kidney disease (CKD) is associated with increased concentration of intracellular calcium, which is pathological and may lead to irreversible damage of cell functions and structures. The aim of our study was to investigate the impact of 6 months vitamin D3 supplementation (14 000 IU/week) on free cytosolic calcium concentration ([Ca2+]i) and on the plasma membrane calcium ATPase (PMCA) activity of patients with CKD stage 2-3. PMCA activity of patients was also compared to that of healthy volunteers. Vitamin D3 supplementation of CKD patients resulted in the decrease of [Ca2+]i (119.79±5.87 nmol/l vs. 105.36± 3.59 nmol/l, n=14, P<0.001), whereas PMCA activity of CKD patients (38.75±22.89 nmol Pi/mg/h) remained unchanged after vitamin D3 supplementation (40.96±17.74 nmol Pi/mg/h, n=14). PMCA activity of early stage CKD patients before supplementation of vitamin D3, was reduced by 34 % (42.01±20.64 nmol Pi/mg/h) in comparison to healthy volunteers (63.68±20.32 nmol Pi/mg/h, n=28, P<0.001). These results indicate that vitamin D3 supplementation had a lowering effect on [Ca2+]i and negligible effect on PMCA activity in CKD patients., M. Morvová Jr., I. Lajdová, V. Spustová, M. Zvarík, L. Šikurová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. The Response of Na+/K+-ATPase of Human Erythrocytes to Green Laser Light Treatment
- Creator:
- Kaššák, P., Šikurová, L., Kvasnička, P., and Bryszewska, M.
- Type:
- article, model:article, and TEXT
- Subject:
- Na+/K+-ATPase activity, Biostimulation, Erythrocyte membrane, Merocyanine 540, and Photodynamic processes
- Language:
- English
- Description:
- The objective of this study was to investigate the response of Na+/K+-ATPase of human erythrocytes to green laser irradiation. Effects of green laser light of fluences 9.5-63.3 J.cm-2 and merocyanine 540-mediated laser light treatment were studied. Isolated erythrocyte membranes (protein concentration of 1 mg/ml) were irradiated by Nd:YAG laser (532 nm, 30 mW) and then incubated in a medium with 2 mM ATP for 30 min. Activity of ATPase was determined colorimetrically by measuring the colored reaction product of liberated inorganic phosphate and malachite green at 640 nm. Contribution of Na+/K+-ATPase to overall phosphate production was determined using ouabain. A positive effect of green laser light on Na+/K+-ATPase activity was observed. The dependence of enzymatically liberated inorganic phosphate on light fluence showed a linear correlation (R2=0.96, P=0.0005) for all fluences applied (9.5-63.3 J.cm-2). On the other hand, MC 540-mediated phototreatment caused a suppression of enzyme activity.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public