Publications by authors named "Plotnikov M"

We studied the radical-binding and antioxidant activities of the alkaloid tryptanthrin (TR) and its new synthetic derivative tryptanthrin oxime (TR-Ox), as well as the cytoprotective activity of TR-Ox under conditions of oxidative stress. The antiradical activity of TR-Ox was revealed in the test of binding with stable chromogen radical 2,2-diphenyl-1-picrylhydrazyl and in the superoxide radical generation test (riboflavin photoreduction reaction with detection by NBT reduction). TR-Ox was inferior to ionol and dihydroquercetin by the antiradical activity.

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In experiments on Wistar rats, the effect of a new selective JNK inhibitor tryptanthrin oxime (TR-Ox) on parameters of systemic hemodynamics, cardiohemodynamics, and post-infarction fibrosis was studied 4 months after acute myocardial ischemia (1 h) followed by reperfusion. TR-Ox was administered intraperitoneally at a dose of 12 mg/kg 20 min before reperfusion, and then once a day for the next 4 days. Administration of TR-Ox to animals in the acute phase of myocardial infarction contributed to more complete preservation of myocardial viability in the delayed period: a relative increase of muscle elements proportion in the scar, a decrease in the formation of connective tissue areas with complete and >50% replacement of the myocardium, and deceleration of fibrotic scarring in myocardium areas distant from the focus of injury, resulting in improved systolic and diastolic myocardial function.

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The neuroprotective activity of tryptanthrin and its oxime was compared in male Wistar rats with a model of intraluminal occlusion of the middle cerebral artery. Neurobehavioral tests were performed 4, 24, and 48 h after focal cerebral infarction (FCI) using a modified neurological severity score (mNSS); additionally, the horizontal stability test, the plantar sensitivity test of the fore and hind limbs, holding on the tilted cage top test, and negative geotaxis test were performed. The size of FCI and the severity of brain tissue swelling were examined on day 2 after occlusion.

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The effect of a new JNK inhibitor IQ-1 (11H-indeno[1,2-b]quinoxalin-11-one oxime) was studied in male Wistar rats in a model of acute myocardial ischemia/reperfusion. Area at risk and myocardial infarct zones were studied in two series of experiments: 16 h after a single dose of IQ-1 (25 mg/kg intraperitoneally during cardiac ischemia) and on day 5 after its course administration (25 mg/kg intraperitoneally during cardiac ischemia and daily over 4 days). On day 5 after ischemia/reperfusion, cardiodynamic indicators were also studied: systolic, end-diastolic, and minimum pressure in the left ventricle, stress-time index, as well as the maximum rates of pressure rise and fall in the left ventricle (+dP/dt and -dP/dt).

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We investigated the effect of a decrease in blood viscosity on the mean BP during isovolumic hemodilution and vasodilating activity of the endothelium in normotensive Wistar rats and spontaneously hypertensive rats (SHR). Blood viscosity was reduced by isovolumic hemodilution (replacement of 10% of circulating blood with an equal volume of plasma). Hemodilution caused the same reduction in blood viscosity by 16% in both groups of rats.

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The activation of -Jun N-terminal kinase (JNK) plays an important role in stroke outcomes. Tryptanthrin-6-oxime (TRYP-Ox) is reported to have high affinity for JNK and anti-inflammatory activity and may be of interest as a promising neuroprotective agent. The aim of this study was to investigate the neuroprotective effects of TRYP-Ox in a rat model of transient focal cerebral ischemia (FCI), which involved intraluminal occlusion of the left middle cerebral artery (MCA) for 1 h.

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Activation of c-Jun N-terminal kinases (JNKs) is involved in myocardial injury, left ventricular remodeling (LV), and heart failure (HF) after myocardial infarction (MI). The aim of this research was to evaluate the effects of a selective JNK inhibitor, 11-indeno [1,2-]quinoxalin-11-one oxime (IQ-1), on myocardial injury and acute myocardial ischemia/reperfusion (I/R) in adult male Wistar rats. Intraperitoneal administration of IQ-1 (25 mg/kg daily for 5 days) resulted in a significant decrease in myocardial infarct size on day 5 after MI.

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Age-related macular degeneration (AMD) is the leading cause of irreversible visual impairment worldwide. The development of AMD is associated with inflammation, oxidative stress, and progressive proteostasis imbalance, in the regulation of which c-Jun N-terminal kinases (JNK) play a crucial role. JNK inhibition is discussed as an alternative way for prevention and treatment of AMD and other neurodegenerative diseases.

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The c-Jun -terminal kinases (JNKs) regulate many physiological processes, including inflammatory responses, morphogenesis, cell proliferation, differentiation, survival, and cell death. Therefore, JNKs represent attractive targets for therapeutic intervention. In an effort to develop improved JNK inhibitors, we synthesized the lithium salt of 11-indeno[1,2-]quinoxaline-11-one oxime () and evaluated its affinity for JNK and biological activity in vitro and in vivo.

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The effect of p-tyrosol on the main hemodynamic parameters and contractile function of the heart was studied and a morphometric assessment of left-ventricular remodeling was performed in Wistar rats 2 months after acute 1-h myocardial ischemia followed by reperfusion. p-Tyrosol in a dose of 20 mg/kg was injected intraperitoneally 5 times: 20 min before the start of reperfusion, 4 h after the start of reperfusion, and then once a day over the next 3 days. Administration of p-tyrosol to animals in the acute period of myocardial infarction slowed down the formation of systolic and diastolic myocardial dysfunction, improved the pumping function of the heart, maintained the hemodynamic parameters at a significantly higher level, and reduced left-ventricular remodeling in the late period of myocardial infarction.

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We developed a model of blood hyperviscosity avoiding extreme impact on the blood. The model shows reproducibility in rat blood under common storage conditions (4±1°C; stabilization with citrate-phosphate-glucose additive solution). Storage of rat blood under these condition leads to impairment of its rheological properties, which manifested in an increase in blood viscosity in a wide range of shear rates (3-300 sec).

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Unlabelled: Despite the widespread occurrence of ischemic diseases of the lower extremities, including atherosclerosis and diseases with an autoimmune component of their pathogenesis, the pathohistological signs of damage and concomitant chronic ischemia, compensatory tissue responses as intracellular and cellular regeneration remain out of the field of vision in researchers.

Objective: To assess the signs of damage (the extent of necrosis and apoptosis, capillary density (CD)) and regeneration (the cross-sectional muscle fiber area (CSMFA), the proportion of centrinucleated muscle fibers (CNMFs), and that of connective tissue), by using the gastrocnemius medial head biopsy specimens obtained from patients with heterogeneous forms of chronic lower limb obliterating diseases (CLLODs).

Subjects And Methods: The investigation included the biopsy specimens obtained from 44 men under 65 years of age (their mean age was 54±9.

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Oximes have been studied for decades because of their significant roles as acetylcholinesterase reactivators. Over the last twenty years, a large number of oximes have been reported with useful pharmaceutical properties, including compounds with antibacterial, anticancer, anti-arthritis, and anti-stroke activities. Many oximes are kinase inhibitors and have been shown to inhibit over 40 different kinases, including AMP-activated protein kinase (AMPK), phosphatidylinositol 3-kinase (PI3K), cyclin-dependent kinase (CDK), serine/threonine kinases glycogen synthase kinase 3 α/β (GSK-3α/β), Aurora A, B-Raf, Chk1, death-associated protein-kinase-related 2 (DRAK2), phosphorylase kinase (PhK), serum and glucocorticoid-regulated kinase (SGK), Janus tyrosine kinase (JAK), and multiple receptor and non-receptor tyrosine kinases.

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(1) Background: Although myelin disruption is an integral part of ischemic brain injury, it is rarely the subject of research, particularly in animal models. This study assessed for the first time, myelin and oligodendrocyte loss in a three-vessel model of global cerebral ischemia (GCI), which causes hippocampal damage. In addition, we investigated the relationships between demyelination and changes in microglia and astrocytes, as well as oligodendrogenesis in the hippocampus; (2) Methods: Adult male Wistar rats ( = 15) underwent complete interruption of cerebral blood flow for 7 min by ligation of the major arteries supplying the brain or sham-operation.

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A novel specific inhibitor of c-Jun N-terminal kinase, 11-indeno[1,2-]quinoxalin-11-one oxime sodium salt (IQ-1S), has a high affinity to JNK3 compared to JNK1/JNK2. The aim of this work was to study the mechanisms of neuroprotective activity of IQ-1S in the models of reversible focal cerebral ischemia (FCI) in Wistar rats. The animals were administered with an intraperitoneal injection of IQ-1S (5 and 25 mg/kg) or citicoline (500 mg/kg).

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c-Jun N-terminal kinases (JNKs) are involved in the myocardial and aortic remodeling, increased arterial tone, and arterial blood pressure elevation associated with hypertension. The aim of the present study was to investigate the antihypertensive effect of a new JNK inhibitor, 1H-indeno[1,2-b]quinoxalin-11-one oxime sodium salt (IQ-1S), on spontaneously hypertensive rats (SHRs). Experiments were performed using normotensive Wistar-Kyoto (WKY) rats and SHRs.

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The use of neuroprotective agents for stroke is pathogenetically justified, but the translation of the results of preclinical studies of neuroprotectors into clinical practice has been a noticeable failure. One of the leading reasons for these failures is the one-target mechanism of their activity. p-Tyrosol (Tyr), a biophenol, is present in a variety of natural sources, mainly in foods, such as olive oil and wine.

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Diamond films are advanced engineering materials for various industrial applications requiring a coating material with extremely high thermal conductivity and low electrical conductivity. An approach for the synthesis of diamond films via high-speed jet deposition of thermally activated gas has been applied. In this method, spatially separated high-speed flows of methane and hydrogen were thermally activated, and methyl and hydrogen radicals were deposited on heated molybdenum substrates.

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This study aimed at assessing the regenerative effect of p-tyrosol in transient global cerebral ischemia modeled in adult male Wistar rats by reversible occlusion of the three major vessels originating from the aortic arch and supplying the blood to the brain. p-Tyrosol was administered intraperitoneally in a dose of 20 mg/kg over 10 days after surgery. The death of NeuN mature neurons and the number of newly formed DCX neurons were assessed in the CA1 field of the hippocampus that is highly susceptible to damage in this model.

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Background New therapeutic strategies, such as the use of agents to correct rheological disorders, are needed for the prevention and treatment of angiopathy in diabetic patients. The aim of this work was to study the antihyperglycaemic, haemorheologic and antioxidant activities of an extract from the flowering plant Lychnis chalcedonica L. (ELC) and 20-hydroxyecdysone using the streptozotocin-induced model of diabetic rats.

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Experimental model of sulpiride-provoked benign prostatic hyperplasia was employed to comparatively assess the effect of phenolic antioxidants (dihydroquercetin, p-thyrozol, dibornol, and prostagenin) on prostate morphology. All examined agents decreased the degree of hyperplasia in acinar epithelium; the greatest efficacy was demonstrated by prostagenin. Moreover, dihydroquercetin and p-thyrozol increased the cross-section area of acinar lumina and prostate volume, which is inadmissible in this pathology.

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c-Jun N-terminal kinase (JNK) is activated by various brain insults and is implicated in neuronal injury triggered by reperfusion-induced oxidative stress. Some JNK inhibitors demonstrated neuroprotective potential in various models, including cerebral ischemia/reperfusion injury. The objective of the present work was to study the neuroprotective activity of a new specific JNK inhibitor, IQ-1S (11-indeno[1,2-]quinoxalin-11-one oxime sodium salt), in the model of global cerebral ischemia (GCI) in rats compared with citicoline (cytidine-5'-diphosphocholine), a drug approved for the treatment of acute ischemic stroke and to search for pleiotropic mechanisms of neuroprotective effects of IQ-1S.

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The effect of phenolic antioxidants (dihydroquercetin, p-tyrosol, dibornol) on the morphology, functions, and redox processes in the reproductive cells of male rats was studied on the model of experimental pathospermia. All antioxidants reduced the percentage of degenerative forms of spermatozoa. Dibornol was most effective.

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Neuroprotective activity of 2,6-diisobornyl-4-methylphenol (Dibornol) was studied under conditions of experimental focal cerebral ischemia/reperfusion modeled by intraluminal occlusion of the left middle cerebral artery for 1 h followed by recirculation. Dibornol administered in a dose of 10 mg/kg intragastrically 24 h and 30 min before and 24 h after focal ischemia/reperfusion modeling reduced the size of the brain infarction zone by 52% (48 h after recirculation) and neurological deficit by 1.7-2.

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We studied the effect of O-((((4-hydroxy-3,5-di(1,7,7-trimethylbicyclo[2.2.1]hept-exo-2-yl) benzyl)oxy)ethyl)-O-(2-hydroxyethyl)-(1→4)-α-D-glucan (D-HES, 80 mg/kg, intravenously) and reference preparation ethylmethylhydroxypyridine succinate (EMHP-S, 50 mg/kg, intravenously) on rat survival and neurological deficit in 24 h after transient global cerebral ischemia in Wistar rats.

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