Relationship between Morphofunctional Changes in Open Traumatic Brain Injury and the Severity of Brain Damage in Rats.

A correlation between the severity of morphofunctional disturbances and the volume of brain tissue injury determined by MRT was demonstrated on the model of open traumatic brain injury in rats. A relationship between the studied parameters (limb placing and beam walking tests and histological changes) and impact force (the height of load fell onto exposed brain surface) was revealed.

Neuroprotective and antiamnesic effect of erythropoietin derivatives after experimental ischemic injury of cerebral cortex.

Using the model of bilateral photothrombosis of the blood vessels in the prefrontal cortex we have shown that new hybrid proteins derived from recombinant human erythropoietin, carbamylated EPO-Fc and EPO-TR fusion proteins, injected intraperitoneally 1 h after ischemic injury contribute to restoration of passive avoidance response formed before photothrombotic injury and reduction in the volume of the ischemic focus. These data attest to nootropic and neuroprotective activities of these hybrid proteins. Carbamylated glycopeptide derivative ЕPO-TR exhibited prolonged neuroprotective properties.

[Comparison of neuroprotective effects of derivatives of eritropoetine by different way of bringing in drugs with model of bilateral photochemically induced thrombosis of the prefrontal cortex of rat brain].

It was stated with model of bilateral photochemically induced thrombosis of the prefrontal cortex by injected intranasally or intraperitoneally in 1h after operation new derivatives of eritropoetine: Epo, Epo-Fc, Epo-Tr provoked neuroprotective and antiamnestic action. Epo-Fc demonstrated more effective action by intranasal injection.

[Experimental approach to the gene therapy of motor neuron disease with the use of genes hypoxia-inducible factors].

Motor neuron disease (MND), or amyotrophic lateral sclerosis, is a fatal neurodegenerative disorder characterized by a progressive loss of motor neurons in the spinal cord and the brain. Several angiogenic and neurogenic growth factors, such as the vascular endothelial growth factor (VEGF), angiogenin (ANG), insulin-like growth factor (IGF) and others, have been shown to promote survival of the spinal motor neurons during ischemia. We constructed recombinant vectors using human adenovirus 5 (Ad5) carrying the VEGF, ANG or IGF genes under the control of the cytomegalovirus promoter. As a model for MND, we employed a transgenic mice strain, B6SJL-Tg (SOD1*G93A)d11 Gur/J that develops a progressive degeneration of the spinal motor neurons caused by the expression of a mutated Cu/Zn superoxide dismutase gene SOD1. Delivery of the therapeutic genes to the spinal motor neurons was done using the effect of the retrograde axonal transport after multiple injections of the Ad5-VEGF, Ad5-ANG and Ad5-IGF vectors and their combinations into the limbs and back muscles of the SOD1(G93A) mice. Viral transgene expression in the spinal cord motor neurons was confirmed by immunocytochemistry and RT-RCR. We assessed the neurological status, motor activity and lifespan of experimental and control animal groups. We discovered that SOD1(G93A) mice injected with the Ad5-VEGF + Ad5-ANG combination showed a 2-3 week delay in manifestation of the disease, higher motor activity at the advanced stages of the disease, and at least a 10% increase in the lifespan compared to the control and other experimental groups. These results support the safety and therapeutic efficacy of the tested recombinant treatment. We propose that the developed experimental MND treatment based on viral delivery of VEGF + ANG can be used as a basis for gene therapy drug development and testing in the preclinical and clinical trials of the MND.

[Morphological study of neuroprotective properties of dipeptide mimetic of nerve growth factor (GK-2h) in focal ischemic damage of rat brain prefrontal cortex].

The neuroprotective effects of dipeptide GK-2h, a mimetic of nerve growth factor, in bifocal photoinduced ischemia in rat brain prefrontal cortex was studied. It was shown that GK-2h, injected intraperitonealy in dose 0.1 mg/kg in 1 h or 4 h after operation and then on 2nd, 4th and 8th days, prevented significantly on 9th day from increasing volume of cortical infarction.

[Neuroprotective and antiamnesic effects of GK-2h dipeptide HNGF mimetic on a model of experimental ischemic stroke of brain cortex prefrontal areas].

Neuroprotective and antiamnesic effects of human nerve growth factor (HNGF) synthetic dipeptide mimetic bis-(N-monosuccinyl-glycyl-lysine)hexamethylenediamide (GK-2h) has been studied on a model of bilateral photochemically induced focal ischemical brain injury in prefrontal cortex of rats. It is established that a single intraperitoneal injection of GK-2h (0.1 mg/kg) 1 h or 4 h after operation, followed by injections on the 2nd, 4th and 8th days after operation, results (on the 9th day) in reduction of the cortical infarction volume by 47 or 65%, and leads to restoration of the passive avoidance reflex (acquired before experimental ischemic insult) by 42 and 60%, respectively. It is concluded that GK-2h possesses significant neuroprotective properties.

Mitochondria-targeted plastoquinone antioxidant SkQR1 decreases trauma-induced neurological deficit in rat.

A protective effect of a mitochondria-targeted antioxidant, a cationic rhodamine derivative linked to a plastoquinone molecule (10-(6'-plastoquinonyl)decylrhodamine-19, SkQR1) was studied in the model of open focal trauma of rat brain sensorimotor cortex. It was found that daily intraperitoneal injections of SkQR1 (100 nmol/kg) for 4 days after the trauma improved performance in a test characterizing neurological deficit and decreased the volume of the damaged cortical area. Our results suggest that SkQR1 exhibits profound neuroprotective effect, which may be explained by its antioxidative activity.

[Neuroprotective effect of recombinant human erythropoietin-loaded poly(lactic-co-glycolic) acid nanoparticles in rats with intracerebral posttraumatic hematoma].

The neuroprotective activity of recombinant human erythropoietin (rhEPO) loaded poly(lactic-co-glycolic) acid (PLGA) nanoparticles has been observed in rats with model intracerebral post-traumatic hematoma (hemorrhagic stroke). It is established that rhEPO-loaded PLGA nanoparticles produce a neuroprotective effect in rats with hemorrhagic stroke, which is manifested by reduced number of lethal outcomes and animals with neurological disorders. Treatment with rhEPO-loaded PLGA prevented amnesia of passive avoidance reflex (PAR), which was produced by the hemorrhagic stroke, and reduced the area of brain damage caused by the intracerebral hematoma. These effects were recorded during one-week observation period. Native rhEPO exhibited a similar, but much less pronounced effect on the major disorders caused by the model hemorrhagic stroke in rats.

Neuroprotective and antiamnestic effect of nerve growth factor dipeptide mimetic GK-2 in experimental ischemic infarction of brain cortex.

The neuroprotective and antiamnestic effects of GK-2 dipeptide (nerve growth factor mimetic) were studied on rats with photoinduced bilateral focal ischemia of the prefrontal cortex. Intraperitoneal injection of GK-2 in a dose of 1 mg/kg on days 1, 2, 4, and 6 postoperation led to a 62% reduction of cortical infarction volume on day 9 and completely preserved conditioned passive avoidance response trained before stroke.

Prevention of neurodegenerative damage to the brain in rats in experimental Alzheimer's disease by adaptation to hypoxia.

We report here studies addressing the possibility of preventing neurodegenerative changes in the brain using adaptation to periodic hypoxia in rats with experimental Alzheimer's disease induced by administration of the neurotoxic peptide fragment of beta-amyloid (Ab) into the basal magnocellular nucleus. Adaptation to periodic hypoxia was performed in a barochamber (4000 m, 4 h per day, 14 days). The following results were obtained 15 days after administration of Ab. 1. Adaptation to periodic hypoxia significantly blocked Ab-induced memory degradation in rats, as assessed by testing a conditioned passive avoidance reflex. 2. Adaptation to periodic hypoxia significantly restricted increases in oxidative stress, measured spectrophotometrically in the hippocampus in terms of the content of thiobarbituric acid-reactive secondary lipid peroxidation products. 3. Adaptation to periodic hypoxia completely prevented the overproduction of NO in the brains of rats with experimental Alzheimer's disease, as measured in terms of increases in tissue levels of stable NO metabolites, i.e., nitrites and nitrates. 4. The cerebral cortex of rats given Ab injections after adaptation to periodic hypoxia did not contain neurons with pathomorphological changes or dead neurons (Nissl staining), which were typical in animals with experimental Alzheimer's disease. Thus, adaptation to periodic hypoxia effectively prevented oxidative and nitrosative stress, protecting against neurodegenerative changes and protecting cognitive functions in experimental Alzheimer's disease.

[Effect of celleks on functional and morphological changes in experimental focal ischemia of prefrontal areas of the rat brain cortex].

The effect of the new original drug celleks on the functional CNS activity and volume of ischemic damage has been studied in the experimental model of photochemically induced bilateral thrombosis of the prefrontal cortex. The chronic (once a day during 4 days) and even single (one hour after the operation) treatment of rats with celleks (intraperitoneal, 3 mg/kg) after the cortical photothrombosis resulted in the restoration of passive avoidance and diminishing of the volume of ischemic damage.

[Prevention of the brain neurodegeneration in rats with experimental Alzheimer's disease by adaptation to hypoxia].

The study focused on a possibility of preventing brain neurodegeneration by adaptation to intermittent hypoxia (AH) in rats with experimental Alzheimer's disease (AD) modeled by injection of a neurotoxic bert-amyloid peptide fragment (Ab) into n. basalis magnocellularis. AH was produ- ced in an altitude chamber (4.000 m; 4 hours daily; 14 days). The following results were obtained after fifteen days of the Ab injection: (1) AH substantially prevented the memory impairment induced by Ab, which was determined using the conditioned avoidance reflex test; (2) the AH significantly restricted the enhanced oxidative stress, which was determined spectrophotometrically by thiobarbituric acid-reactive substance level in the hippocampus; (3) the AH completely prevented Ab-induced nitric oxide (NO) overproduction in brain, which was measured by tissue level of nitrite and nitrate; (4) pathologically changed and dead neurons (Niessle staining) were absent in the brain cortex of rats exposed to AH before the Ab injection. Therefore AH seems to effectively prevent oxidative and nitrosative stress thereby providing protection of brain against neurodegeneration and preservation of cognitive function in experimental AD.

Mitochondria-targeted plastoquinone derivatives as tools to interrupt execution of the aging program. 2. Treatment of some ROS- and age-related diseases (heart arrhythmia, heart infarctions, kidney ischemia, and stroke).

Effects of 10-(6'-plastoquinonyl) decyltriphenylphosphonium (SkQ1) and 10-(6'-plastoquinonyl) decylrhodamine 19 (SkQR1) on rat models of H2O2- and ischemia-induced heart arrhythmia, heart infarction, kidney ischemia, and stroke have been studied ex vivo and in vivo. In all the models listed, SkQ1 and/or SkQR1 showed pronounced protective effect. Supplementation of food with extremely low SkQ1 amount (down to 0.02 nmol SkQ1/kg per day for 3 weeks) was found to abolish the steady heart arrhythmia caused by perfusion of isolated rat heart with H2O2 or by ischemia/reperfusion. Higher SkQ1 (125-250 nmol/kg per day for 2-3 weeks) was found to decrease the heart infarction region induced by an in vivo ischemia/reperfusion and lowered the blood levels of lactate dehydrogenase and creatine kinase increasing as a result of ischemia/reperfusion. In single-kidney rats, ischemia/reperfusion of the kidney was shown to kill the majority of the animals in 2-4 days, whereas one injection of SkQ1 or SkQR1 (1 micromol/kg a day before ischemia) saved lives of almost all treated rats. Effect of SkQR1 was accompanied by decrease in ROS (reactive oxygen species) level in kidney cells as well as by partial or complete normalization of blood creatinine and of some other kidney-controlled parameters. On the other hand, this amount of SkQ1 (a SkQ derivative of lower membrane-penetrating ability than SkQR1) saved the life but failed to normalize ROS and creatinine levels. Such an effect indicates that death under conditions of partial kidney dysfunction is mediated by an organ of vital importance other than kidney, the organ in question being an SkQ1 target. In a model of compression brain ischemia/reperfusion, a single intraperitoneal injection of SkQR1 to a rat (1 micromol/kg a day before operation) effectively decreased the damaged brain area. SkQ1 was ineffective, most probably due to lower permeability of the blood-brain barrier to this compound.

[Antioxidants in complex treatment of Parkinson's disease].

Experimental and clinical study of mexidol efficacy in the complex therapy of Parkinson's disease has been carried out. It is shown that in a Parkinsonian animal model using oxotremorine, mexidol reduces Parkinsonian symptoms and decreases expression of neurophysiological changes caused by oxotremorine. Neurohistological study of substantia nigra neurons in a Parkinsonian model using MPTP revealed a neuroprotective effect of mexidol. An assignment of mexidol (4,0 ml intravenous in drops during 10 days) to patients with Parkinson's disease, receiving the basic therapy with antiparkinsonic drugs, reduced tremor, rigidity and bradykinesia. The most marked effect was observed in patients with prevalence of trembling symptoms at early stages of the disease. The results of clinical study have been confirmed by electromyographic and electroneuromyographic data.

Neuroprotective activity of proproten in rats with experimental local photothrombosis of the prefrontal cortex.

Proproten (ultralow doses of antibodies to S100 protein) exhibited neuroprotective activity in rats with experimental photochemical thrombosis of the prefrontal cortex. Proproten was more potent than standard neuroprotectors piracetam and vinpocetine in alleviating the signs of memory disorders produced by ischemic injury. Pathomorphological study of the damaged area confirmed the neuroprotective effect of Proproten.

Antiamnesic effect of acyl-prolyl-containing dipeptide (GVS-111) in compression-induced damage to frontal cortex.

Antiamnestic effect of acyl-prolyl-containing dipeptide GVS-111 was demonstrated in rats with bilateral compression-induced damage to the frontal cortex. Both intraperitoneal and oral administration of the dipeptide improved retrieval of passive avoidance responses in rats with compression-induced cerebral ischemia compared to untreated controls.

Memory restoring and neuroprotective effects of the proline-containing dipeptide, GVS-111, in a photochemical stroke model.

Local thrombosis of the frontal cortex (Fr1 and Fr3 fields), caused by combination of the intravenous photosensitive dye Rose Bengal administration with focused high-intensity illumination of the frontal bone, was shown to provoke a pronounced deficit in step-through passive avoidance performance in rats without concomitant motor disturbances. N-Phenylacetyl-L-prolylglycine ethyl ester (GVS-111) administered intravenously at a dose of 0.5 mg/kg/day, for the first time 1 h after ischaemic lesion and then for 9 post-operative days, with the last administration 15 min before testing, attenuated the deficit. This treatment significantly diminished the volume of the infarcted area. Thus, post-ischaemic injection of GVS-111 demonstrated both cognition-restoring and neuroprotective properties. The cognition-restoring effect is probably based on an increase in neocortical and hippocampal neuronal plasticity. Neuroprotective effects of GVS-111 combine antioxidant activity with the ability to attenuate glutamate-provoked neurotoxicity and block voltage-gated ionic channels, i.e. the compound mitigates the main metabolic shifts involved in pathogenesis of brain ischaemia.

[Behavioral and morphologic disorders caused by bilateral photoinduced thrombosis of the cerebral vessels of the frontal cortex in rats]. / Povedencheskie i morfologicheskie narusheniia, vyzvannye dvustoronnim fotoindutsirovannym trombozom mozgovykh sosudov lobnoi kory mozga krys.

Chronic experiments were made on 35 non-inbred male rats (200-250 g b.w.) to study functional and morphological consequences of photochemical thrombosis of frontal cortex vessels Defects in CNS function were assessed by conditioned reflexes of passive avoidance and behavior in open field tests. The size of the ischemic focus and perifocal lesion were measured on the stained histological sections. Correction of the postischemic impairment was done by intraperitoneal injection of a new nootrop--ethyl ether of N-phenylacetylprolylglycine (GVS-111)--in a dose 0.8 mg/kg/day. The results of the experiments show a significant neuroprotective and nootropic action of GVS-111 in focal ischemic brain damage.