Yuriy Arkhipenko - Academia.edu (original) (raw)

Papers by Yuriy Arkhipenko

Research paper thumbnail of Adaptation to Intermittent Hypoxia/Hyperoxia Enhances Efficiency of Exercise Training

Springer eBooks, 2012

To maintain physical performance and cognitive functions in the elderly, multimodal training prog... more To maintain physical performance and cognitive functions in the elderly, multimodal training programs (MTP) are used, which are based on physical training, physiotherapy procedures, psychological training, etc. To increase the efficiency of MTP in the elderly, it is suggested to apply a new variant of adaptation to interval normobaric hypoxia, interval hypoxic-hyperoxic training (IHHT). A placebo-controlled clinical trial included 34 patients aged 64-92 years of the day geriatric hospital of the Klagenfurt Clinic (Carinthia, Austria) who were randomized into two groups: experimental (EG), those who received MTP and IHHT, and control (CG), those who passed the course of MTP during the simulation of IHHT procedures. Before and after the rehabilitation course, cognitive functions and exercise endurance of the patients were evaluated using the dementia detection test DemTect, the clock-drawing test, and a 6-minute walk test (6MWT). During the course of IHHT, cognitive capabilities of EG patients significantly improved in comparison with CG patients: the increase in values in the dementia test was +16.7% (in CG +0.39%, p < 0.001), and that in the clock-drawing test was +10.7% (in CG-8%, p = 0.031). The distance covered in the 6-minute test increased in both the groups but significantly more in OG, 24.1% (in CG +10.8%, p = 0.021). Direct significant correlations between increment in exercise tolerance and cognitive tests were revealed. Thus, the inclusion of procedures for adaptation to interval hypoxia-hyperoxia in MTP in the elderly leads to a significant increase in their effectiveness, which is manifested in the improvement of cognitive functions and physical endurance. IHHT procedures are well tolerated and do not cause side effects.

Research paper thumbnail of Calpains: physiological and pathophysiological significance

Pathophysiology, Jul 1, 1999

The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represente... more The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represented by two main isoforms, calpain 1 and calpain 2, as well as by tissue-specific enzymes. These enzymes take part in some physiological processes and are responsible for certain pathological states. The versatility of intracellular Ca 2 + mediating the majority of cellular processes is reflected on the calpain system, i.e. it activates the functional reserves of the cell at moderate Ca 2 + concentrations and causes protein degradation at excessive Ca 2 +. Besides, the activity of the calpain system of the cell is regulated by the concentration of its specific inhibitor, calpastatin, as well as by phosphorylation-dephosphorylation of proteins. Calpains can function both inside the cell and outside it (in the extracellular matrix) and exist both in soluble and membrane-bound states, where it is the most active. Calpains induce cell degradation in some pathologies and in apoptosis. Preliminary modification of proteins or their membrane microenvironment initiates enhanced proteolysis of cytosolic and membrane-bound proteins and enzymes. The key role of calpains in the development of many pathological states testifies to the high pathophysiological significance of this proteolytic system in the organism.

Research paper thumbnail of Adaptation to Interval Hypoxiahyperoxia Improves Exercise Tolerance in Professional Athletes: Experimental Substantiation and Applied Approbation

European Scientific Journal, ESJ, Jun 29, 2014

Research paper thumbnail of Calpains: physiological and pathophysiological significance

Pathophysiology, 1999

The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represente... more The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represented by two main isoforms, calpain 1 and calpain 2, as well as by tissue-specific enzymes. These enzymes take part in some physiological processes and are responsible for certain pathological states. The versatility of intracellular Ca2+ mediating the majority of cellular processes is reflected on the calpain

Research paper thumbnail of Calpains: physiological and pathophysiological significance

Pathophysiology, 1999

The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represente... more The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represented by two main isoforms, calpain 1 and calpain 2, as well as by tissue-specific enzymes. These enzymes take part in some physiological processes and are responsible for certain pathological states. The versatility of intracellular Ca2+ mediating the majority of cellular processes is reflected on the calpain

Research paper thumbnail of Adaptation to Intermittent Hypoxia/Hyperoxia Enhances Efficiency of Exercise Training

Intermittent Hypoxia and Human Diseases, 2012

Research paper thumbnail of Calcium uptake in sarcoplasmic reticulum of rat lateral gastrocnemius muscle after hindlimb suspension

Pathophysiology, 1994

Previous studies on rats have shown that hindlimb unweighting caused a striking atrophy of the hi... more Previous studies on rats have shown that hindlimb unweighting caused a striking atrophy of the hindlimb musculature (Oganov, 1980, Winiarsky,1987. Because the sarcoplasmic reticulum (SR) is closely involved in skeletal muscle function, an alteration in its structure and/or function could be associated with the development of muscle atrophy.

Research paper thumbnail of Correlation between activity of antioxidant systems and endogenous lipid peroxidation in the left and right ventricular myocardium

Bulletin of Experimental …, 1984

... Soe., 7_, 445 (1954). 8. AS Csallany and KL Ayaz, Lipids, 1_11, 412 (1976). 9. GC Dalli and P... more ... Soe., 7_, 445 (1954). 8. AS Csallany and KL Ayaz, Lipids, 1_11, 412 (1976). 9. GC Dalli and P. Chiaverini, Minerva Cardioangiol., 7, 579 (1959). 10. J. Folch, M. Lees, and GH Sloane-Stanley, J. Biol. Chem., 22__~6, 497 (1957). 11. I. Fridovich, Acc. Chem. Res., 5, 321 {1972). ...

Research paper thumbnail of Ca2+ transport of the skeletal muscle sarcoplasmic reticulum during readaptation of rats after a 40-day load relief on the hind paws

Bulletin of Experimental Biology and Medicine, 1994

The rate of Ca 2 § accumulation in the sarcoplasmic reticulum of the skeletal muscle (m. gastrocn... more The rate of Ca 2 § accumulation in the sarcoplasmic reticulum of the skeletal muscle (m. gastrocnemius lateralis, m. vastus medialis, and m. soleus) is studied in rats under conditions of functional off-loading of the hind paws (suspending animals by the taft). The rate of Ca 2 § transport in the sarcoplasmic reticulum is shown to be stepped up in all these muscles. In the sarcoplasmic reticulum of m. gastrocnemius lateralis and m. vastus medialis the Ca 2 § transport rate reliably drops, which does not occur in m. soleus. During a 2-week period of readaptation of animals suspended for 40 days, the Ca:+-transporting function of the m. soleus sarcoplasmic reticulum gradually recovers to reach the control values, whereas the time course of recovery of Ca2+-pump activity in the sarcoplasmic reticulum of m. gastrocnemius lateralis and m. vastus medialis has a phasic pattern.

Research paper thumbnail of Ca2+ transport in the myocardial sarcoplasmic reticulum of rats during antiorthostatic off-loading and during readaptation

Bulletin of Experimental Biology and Medicine, 1994

The rate of Ca 2 § accumulation in the myocardial sarcoplasmic reticulum is studied in experiment... more The rate of Ca 2 § accumulation in the myocardial sarcoplasmic reticulum is studied in experiments on rats under conditions of hind paw functional off-loading by suspending animals by the tail for 1 to 40 days,-as well as during a 2-week period of readaptation after a 40-day load relief. The rate of Ca 2~ transport in the myocardial sarcoplasmic reticulum reliably drops (by 33%) after 40 days of suspension. At earlier stages of off-loading Ca-pump activity in the sarcoplasmic reticulum does not change reliably. After resumption of the loads in animals suspended for 40 days, the transporting function of the myocardial sarcoplasmic reticulum rapidly reverts to the control level, which is indicative of a reversible pattern of load relief-induced changes in the rate of Ca 2 § transport.

Research paper thumbnail of Activity of antioxidant enzymes and lipid peroxidation in intact and mutagen-treated NZW mice

Bulletin of Experimental Biology and Medicine, 1997

Catalase and superoxide dismutase activities in the liver of NZW mice are 29.3 μmol H2O2/min�mg p... more Catalase and superoxide dismutase activities in the liver of NZW mice are 29.3 μmol H2O2/min�mg protein and 10.6 U/mg protein, respectively. The rate of accumulation of lipid peroxidation (LPO) products is low within the first 60 min of incubation of liver homogenates with ascorbate and then rapidly increases. A similar process is observed with Fe+ascorbate system, where LPO rate is

Research paper thumbnail of Disturbances of the Ca++ transport enzyme system in membranes of the sarcoplasmic reticulum caused by hydroperoxides of phospholipids and of fatty acids

Bulletin of Experimental Biology and Medicine, 1979

ABSTRACT

Research paper thumbnail of Antioxidative enzyme activity and peroxide metabolism in the lens and their role in cataract formation

Bulletin of Experimental Biology and Medicine, 1987

Research paper thumbnail of Effect of vitamin E deficiency on cardiac arrhythmias induced by acute ischemia

Bulletin of Experimental Biology and Medicine, 1986

Research paper thumbnail of Accumulation of lipid peroxidation products in the lens in cataract

Bulletin of Experimental Biology and Medicine, 1985

A study was made of the content of lipid peroxidation products (LPP) in the lenses extracted duri... more A study was made of the content of lipid peroxidation products (LPP) in the lenses extracted during operations for cataract as well as in transparent human lenses. In a mature cataract, the elevated content of primary, secondary and end products of lipid peroxidation (diene and triene conjugates, Schiff bases) was revealed. The content of LPP was identical in different clinical patterns of a mature cataract (senile, traumatic, complicated), which points to the universal role of lipid peroxidation in lenticular opacity.

Research paper thumbnail of Injury to the Ca++-transporting system of the sarcoplasmic reticulum of the heart due to emotional and pain-induced stress

Bulletin of Experimental Biology and Medicine, 1981

Research paper thumbnail of Role of lipid peroxidation in inhibition of cardiac Na,K-ATP-ase during stress

Bulletin of Experimental Biology and Medicine, 1983

Research paper thumbnail of Ischemic damage to the sarcoplasmic reticulum of skeletal muscles: The role of lipid peroxidation

Bulletin of Experimental Biology and Medicine, 1977

The development of ischemia was shown to be accompanied by inhibition of the Ca2+ enzyme transpor... more The development of ischemia was shown to be accompanied by inhibition of the Ca2+ enzyme transport system (ETS) (a decrease in the Ca2+/ATP ratio and in activity of Ca2+-dependent ATPase), which correlates with accumulation of the primary and secondary molecular lipid peroxidation products (POL) in vivo and in the membranes of the sarcoplasmic reticulum (SR) of the skeletal muscles. Administration of antioxidants (2,6-di-tert-butyl-4-methylphenol, a-tocopherol) prevents activation of POL in the ischemic muscle and partially protects the Ca2+ ETS against injury. Restoration of the blood flow after prolonged ischemia leads to further inhibition of the Ca2+ ETS while the concentration of POL products remains unchanged.

Research paper thumbnail of Effect of a polyunsaturated fatty acid-enriched diet on the state of the Ca-transporting system of the sarcoplasmic reticulum in the myocardium

Bulletin of Experimental Biology and Medicine, 1993

Research paper thumbnail of Ca2+ transport by rat skeletal muscle sarcoplasmic reticulum during load relief of the hind paws

Bulletin of Experimental Biology and Medicine, 1993

Research paper thumbnail of Adaptation to Intermittent Hypoxia/Hyperoxia Enhances Efficiency of Exercise Training

Springer eBooks, 2012

To maintain physical performance and cognitive functions in the elderly, multimodal training prog... more To maintain physical performance and cognitive functions in the elderly, multimodal training programs (MTP) are used, which are based on physical training, physiotherapy procedures, psychological training, etc. To increase the efficiency of MTP in the elderly, it is suggested to apply a new variant of adaptation to interval normobaric hypoxia, interval hypoxic-hyperoxic training (IHHT). A placebo-controlled clinical trial included 34 patients aged 64-92 years of the day geriatric hospital of the Klagenfurt Clinic (Carinthia, Austria) who were randomized into two groups: experimental (EG), those who received MTP and IHHT, and control (CG), those who passed the course of MTP during the simulation of IHHT procedures. Before and after the rehabilitation course, cognitive functions and exercise endurance of the patients were evaluated using the dementia detection test DemTect, the clock-drawing test, and a 6-minute walk test (6MWT). During the course of IHHT, cognitive capabilities of EG patients significantly improved in comparison with CG patients: the increase in values in the dementia test was +16.7% (in CG +0.39%, p < 0.001), and that in the clock-drawing test was +10.7% (in CG-8%, p = 0.031). The distance covered in the 6-minute test increased in both the groups but significantly more in OG, 24.1% (in CG +10.8%, p = 0.021). Direct significant correlations between increment in exercise tolerance and cognitive tests were revealed. Thus, the inclusion of procedures for adaptation to interval hypoxia-hyperoxia in MTP in the elderly leads to a significant increase in their effectiveness, which is manifested in the improvement of cognitive functions and physical endurance. IHHT procedures are well tolerated and do not cause side effects.

Research paper thumbnail of Calpains: physiological and pathophysiological significance

Pathophysiology, Jul 1, 1999

The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represente... more The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represented by two main isoforms, calpain 1 and calpain 2, as well as by tissue-specific enzymes. These enzymes take part in some physiological processes and are responsible for certain pathological states. The versatility of intracellular Ca 2 + mediating the majority of cellular processes is reflected on the calpain system, i.e. it activates the functional reserves of the cell at moderate Ca 2 + concentrations and causes protein degradation at excessive Ca 2 +. Besides, the activity of the calpain system of the cell is regulated by the concentration of its specific inhibitor, calpastatin, as well as by phosphorylation-dephosphorylation of proteins. Calpains can function both inside the cell and outside it (in the extracellular matrix) and exist both in soluble and membrane-bound states, where it is the most active. Calpains induce cell degradation in some pathologies and in apoptosis. Preliminary modification of proteins or their membrane microenvironment initiates enhanced proteolysis of cytosolic and membrane-bound proteins and enzymes. The key role of calpains in the development of many pathological states testifies to the high pathophysiological significance of this proteolytic system in the organism.

Research paper thumbnail of Adaptation to Interval Hypoxiahyperoxia Improves Exercise Tolerance in Professional Athletes: Experimental Substantiation and Applied Approbation

European Scientific Journal, ESJ, Jun 29, 2014

Research paper thumbnail of Calpains: physiological and pathophysiological significance

Pathophysiology, 1999

The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represente... more The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represented by two main isoforms, calpain 1 and calpain 2, as well as by tissue-specific enzymes. These enzymes take part in some physiological processes and are responsible for certain pathological states. The versatility of intracellular Ca2+ mediating the majority of cellular processes is reflected on the calpain

Research paper thumbnail of Calpains: physiological and pathophysiological significance

Pathophysiology, 1999

The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represente... more The system of Ca-dependent neutral proteases, commonly known as the calpain system, is represented by two main isoforms, calpain 1 and calpain 2, as well as by tissue-specific enzymes. These enzymes take part in some physiological processes and are responsible for certain pathological states. The versatility of intracellular Ca2+ mediating the majority of cellular processes is reflected on the calpain

Research paper thumbnail of Adaptation to Intermittent Hypoxia/Hyperoxia Enhances Efficiency of Exercise Training

Intermittent Hypoxia and Human Diseases, 2012

Research paper thumbnail of Calcium uptake in sarcoplasmic reticulum of rat lateral gastrocnemius muscle after hindlimb suspension

Pathophysiology, 1994

Previous studies on rats have shown that hindlimb unweighting caused a striking atrophy of the hi... more Previous studies on rats have shown that hindlimb unweighting caused a striking atrophy of the hindlimb musculature (Oganov, 1980, Winiarsky,1987. Because the sarcoplasmic reticulum (SR) is closely involved in skeletal muscle function, an alteration in its structure and/or function could be associated with the development of muscle atrophy.

Research paper thumbnail of Correlation between activity of antioxidant systems and endogenous lipid peroxidation in the left and right ventricular myocardium

Bulletin of Experimental …, 1984

... Soe., 7_, 445 (1954). 8. AS Csallany and KL Ayaz, Lipids, 1_11, 412 (1976). 9. GC Dalli and P... more ... Soe., 7_, 445 (1954). 8. AS Csallany and KL Ayaz, Lipids, 1_11, 412 (1976). 9. GC Dalli and P. Chiaverini, Minerva Cardioangiol., 7, 579 (1959). 10. J. Folch, M. Lees, and GH Sloane-Stanley, J. Biol. Chem., 22__~6, 497 (1957). 11. I. Fridovich, Acc. Chem. Res., 5, 321 {1972). ...

Research paper thumbnail of Ca2+ transport of the skeletal muscle sarcoplasmic reticulum during readaptation of rats after a 40-day load relief on the hind paws

Bulletin of Experimental Biology and Medicine, 1994

The rate of Ca 2 § accumulation in the sarcoplasmic reticulum of the skeletal muscle (m. gastrocn... more The rate of Ca 2 § accumulation in the sarcoplasmic reticulum of the skeletal muscle (m. gastrocnemius lateralis, m. vastus medialis, and m. soleus) is studied in rats under conditions of functional off-loading of the hind paws (suspending animals by the taft). The rate of Ca 2 § transport in the sarcoplasmic reticulum is shown to be stepped up in all these muscles. In the sarcoplasmic reticulum of m. gastrocnemius lateralis and m. vastus medialis the Ca 2 § transport rate reliably drops, which does not occur in m. soleus. During a 2-week period of readaptation of animals suspended for 40 days, the Ca:+-transporting function of the m. soleus sarcoplasmic reticulum gradually recovers to reach the control values, whereas the time course of recovery of Ca2+-pump activity in the sarcoplasmic reticulum of m. gastrocnemius lateralis and m. vastus medialis has a phasic pattern.

Research paper thumbnail of Ca2+ transport in the myocardial sarcoplasmic reticulum of rats during antiorthostatic off-loading and during readaptation

Bulletin of Experimental Biology and Medicine, 1994

The rate of Ca 2 § accumulation in the myocardial sarcoplasmic reticulum is studied in experiment... more The rate of Ca 2 § accumulation in the myocardial sarcoplasmic reticulum is studied in experiments on rats under conditions of hind paw functional off-loading by suspending animals by the tail for 1 to 40 days,-as well as during a 2-week period of readaptation after a 40-day load relief. The rate of Ca 2~ transport in the myocardial sarcoplasmic reticulum reliably drops (by 33%) after 40 days of suspension. At earlier stages of off-loading Ca-pump activity in the sarcoplasmic reticulum does not change reliably. After resumption of the loads in animals suspended for 40 days, the transporting function of the myocardial sarcoplasmic reticulum rapidly reverts to the control level, which is indicative of a reversible pattern of load relief-induced changes in the rate of Ca 2 § transport.

Research paper thumbnail of Activity of antioxidant enzymes and lipid peroxidation in intact and mutagen-treated NZW mice

Bulletin of Experimental Biology and Medicine, 1997

Catalase and superoxide dismutase activities in the liver of NZW mice are 29.3 μmol H2O2/min�mg p... more Catalase and superoxide dismutase activities in the liver of NZW mice are 29.3 μmol H2O2/min�mg protein and 10.6 U/mg protein, respectively. The rate of accumulation of lipid peroxidation (LPO) products is low within the first 60 min of incubation of liver homogenates with ascorbate and then rapidly increases. A similar process is observed with Fe+ascorbate system, where LPO rate is

Research paper thumbnail of Disturbances of the Ca++ transport enzyme system in membranes of the sarcoplasmic reticulum caused by hydroperoxides of phospholipids and of fatty acids

Bulletin of Experimental Biology and Medicine, 1979

ABSTRACT

Research paper thumbnail of Antioxidative enzyme activity and peroxide metabolism in the lens and their role in cataract formation

Bulletin of Experimental Biology and Medicine, 1987

Research paper thumbnail of Effect of vitamin E deficiency on cardiac arrhythmias induced by acute ischemia

Bulletin of Experimental Biology and Medicine, 1986

Research paper thumbnail of Accumulation of lipid peroxidation products in the lens in cataract

Bulletin of Experimental Biology and Medicine, 1985

A study was made of the content of lipid peroxidation products (LPP) in the lenses extracted duri... more A study was made of the content of lipid peroxidation products (LPP) in the lenses extracted during operations for cataract as well as in transparent human lenses. In a mature cataract, the elevated content of primary, secondary and end products of lipid peroxidation (diene and triene conjugates, Schiff bases) was revealed. The content of LPP was identical in different clinical patterns of a mature cataract (senile, traumatic, complicated), which points to the universal role of lipid peroxidation in lenticular opacity.

Research paper thumbnail of Injury to the Ca++-transporting system of the sarcoplasmic reticulum of the heart due to emotional and pain-induced stress

Bulletin of Experimental Biology and Medicine, 1981

Research paper thumbnail of Role of lipid peroxidation in inhibition of cardiac Na,K-ATP-ase during stress

Bulletin of Experimental Biology and Medicine, 1983

Research paper thumbnail of Ischemic damage to the sarcoplasmic reticulum of skeletal muscles: The role of lipid peroxidation

Bulletin of Experimental Biology and Medicine, 1977

The development of ischemia was shown to be accompanied by inhibition of the Ca2+ enzyme transpor... more The development of ischemia was shown to be accompanied by inhibition of the Ca2+ enzyme transport system (ETS) (a decrease in the Ca2+/ATP ratio and in activity of Ca2+-dependent ATPase), which correlates with accumulation of the primary and secondary molecular lipid peroxidation products (POL) in vivo and in the membranes of the sarcoplasmic reticulum (SR) of the skeletal muscles. Administration of antioxidants (2,6-di-tert-butyl-4-methylphenol, a-tocopherol) prevents activation of POL in the ischemic muscle and partially protects the Ca2+ ETS against injury. Restoration of the blood flow after prolonged ischemia leads to further inhibition of the Ca2+ ETS while the concentration of POL products remains unchanged.

Research paper thumbnail of Effect of a polyunsaturated fatty acid-enriched diet on the state of the Ca-transporting system of the sarcoplasmic reticulum in the myocardium

Bulletin of Experimental Biology and Medicine, 1993

Research paper thumbnail of Ca2+ transport by rat skeletal muscle sarcoplasmic reticulum during load relief of the hind paws

Bulletin of Experimental Biology and Medicine, 1993