Combined Preconditioning Reduces the Negative Influence of Cerebral Ischemia on the Morphofunctional Condition of CNS.

We studied the influence of combined preconditioning (compound pQ-4 and moderate hypoxia) on morphometrical parameters of neuronal populations in hippocampal fields CA1 and CA3 in rats after bilateral ligation of the common carotid artery. Preconditioning produced a neuroprotective effect, improved survival of pyramidal neurons in the early and delayed periods of modeled ischemia, prevented the formation of necrotic and apoptotic neurons and hyperactivation of microglia, and protected endotheliocytes. The positive influence of preconditioning factors on the morphometric parameters of the brain under ischemic conditions agrees with the results of behavioral tests (open field and elevated plus maze) that demonstrated increased locomotor activity and exploratory behavior of animals.

[Erythropoietin and vascular endothelial growth factor level in normoxia and in cerebral ischemia under pharmacological and hypoxic preconditioning]. / Soderzhanie éritropoétina i faktora rosta éndoteliia sosudov v usloviiakh normoksii i pri ishemii golovnogo mozga pod deistviem farmakologicheskogo i gipoksicheskogo prekonditsionirovaniia.

The level of erythropoietin (EPO) and vascular endothelial growth factor (VEGF-A) was investigated in blood serum and brain of Wistar rats by the enzyme immunoassay with specific rat antibodies. These growth factors are actively studied as biomarkers of ischemia or cytoprotection, as well as targets for agents initiating preconditioning (PreC). Pharmacological (amtizol administration), hypoxic (hypobaric hypoxia), and combined PreC (amtizol+hypobaric hypoxia) were used as neuroprotective approaches in this experimental work. In normoxia groups blood and brain tissue were collected 1 h (early period) or 48 h (delayed period) after the PreC. In addition we studied groups of animals with cerebral ischemia (induced by bilateral ligation of the common carotid arteries) 1 h and 48 h after the combined PreC: the levels of EPO and VEGF-A in the blood serum and the brain supernatant were determined in one day after the ligation. Experiments have shown that amtizol (3,5-diamino-1,2,4-thiadiazole) in normoxia increased the EPO level in the brain, and did not change EPO in blood serum and VEGF-A levels in both serum and the brain. A three-day (60 min exposure with 48 h intervals) hypobaric hypoxia (410 mm Hg) increased EPO and VEGF-A in the blood serum and brain tissues, but in most experimental groups differences did not reach the level of statistical significance versus intact control. The combined PreC was accompanied by a significant increase of EPO and VEGF-A in normoxia conditions both in early and delayed period of PreC. In cerebral ischemia the EPO level in the blood serum and brain tissues was higher than in intact control. The serum level of VEGF-A of the ischemia control group tended to increase while the brain level of VEGF-A remained basically unchanged versus the intact control group. In combined PreC before ischemia, the EPO level was lower in serum as compared with the ischemia control in the delayed PreC period, but did not differ significantly from the ischemia control in serum in early period and in brain tissues in both PreC periods. The VEGF-A level in the groups of combined PreC was significantly lower in serum as compared with the ischemia control in both the early and delayed PreC; in brain tissues it did not differ from the level of both the intact and ishemia control in early PreC period and was higher than in both control groups in the delayed PreC period.

Signal Mechanism of the Protective Effect of Combined Preconditioning by Amtizole and Moderate Hypoxia.

The content of regulatory proteins involved in adaptation to hypoxia and ischemia was studied in brain rat homogenate under conditions of normoxia and after bilateral ligation of the common carotid arteries. Preconditioning with amtizole in combination with moderate hypoxia increased the levels of HIF-1α, erythropoietin, vascular endothelial growth factor under conditions of normoxia. During experimental ischemia, combined preconditioning led to stabilization of the content of these regulatory proteins at the level of intact control and to a decrease in glycogen synthase-3ß kinase activity. This pattern of changes in regulatory proteins was noted during the early and late periods of preconditioning.

[Experience in using Prolia in patients with postmenopausal osteoporosis in clinical practice]. / Opyt primeneniia preparata Prolia u patsientok s postmenopauzal'nym osteoporozom v klinicheskoi praktike.

AIM: To evaluate the efficiency and safety of long-term Prolia therapy in patients with postmenopausal osteoporosis (OP). SUBJECTS AND METHODS: The open prospective study enrolled 98 women (mean age, 68±9 years; mean menopause duration, 17±4 years) with postmenopausal OP, who were followed up in an outpatient setting at the National Medical Research Center for Preventive Medicine and who had been treated with denosumab 60 mg subcutaneously every 6 months for 12 months or more. The maximum follow-up period was 4 years: 48, 29, 11, and 10 patients were treated for 12, 24, 36, and 48 months, respectively. The patients were allocated into 2 groups: those who received and those who had not previously received antiosteoporotic therapy. Bone mineral density (BMD) was measured using dual-energy X-ray densitometry of the lumbar spine (LI-LIV) and proximal femur (PF). The ten-year probability of major osteoporotic fractures was estimated once in 72 patients not previously receiving antiosteoporotic therapy before the prescription of denosumab. RESULTS: In the patients not previously receiving therapy, the median 10-year probability of major fractures using the FRAX algorithm was 14.9%; that of femoral neck (FN) fractures was 3.7%. During denosumab treatment, the BMD increase in the lumbar spine was 4.2% at 12 months, 7.5% at 24 months, was 8.8% at 36 months; that in FN was 3.1, 3.9, and 5.3%, that in PF was 2.8, 4.1, and 5%; and that in the 1/3 forearm was 0.9, 1.4, and 2.6%, respectively (p < 0.001). In the persons receiving and not previously receiving the therapy, the BMD increase was similar, i.e. there was an additional positive effect when switching to denosumab. The decrease in the serum concentration of C-terminal telopeptide of type I collagen (CTX-I) was 54% at 6 months after initiation of denosumab therapy (p < 0.001) and 72% at 12 months (p<0.001); and the achieved marker level remained unchanged at 48 months. Transition from the OP zone to osteopenia one was noted in 23 patients with low BMD (T-score -2.5 SD) in LI-LII and in 12 patients with that in FN at 12 months of denosumab therapy and this was in 25 patients at 24 months. Nine-eight patients receiving the first Prolia injection refused to continue treatment on their own; adverse events were not the reason for drug discontinuation. CONCLUSION: Therapy with denosumab was effective in increasing BMD in routine outpatient practice and in allowing 25% of patients to achieve target values of this indicator. The marked decrease in the level of the bone resorption marker STX suggested that the drug had antiresorptive potency. The frequency of adverse reactions was low, confirming the good tolerability and safety profile of the drug. The convenience of the scheme and route of drug administration contributed to strict compliance with the doctor's recommendations. Denosumab was effective in increasing BMD not only in untreated patients, but also in those who had previously received antiosteoporotic therapy. The pharmacokinetic characteristics of denosumab, which contribute to its uniform distribution in trabecular and cortical bone tissue, regardless of active bone remodeling, and the fact that the clearance of the drug is independent of kidney function offer an advantage of administering the drug to patients with significant loss of FN and radius BMD and of reducing kidney function.

Neuroprotective Effect of Antioxidants and Moderate Hypoxia as Combined Preconditioning in Cerebral Ischemia.

We studied combined effect of moderate hypoxia and compounds pQ-4, pQ-915, pQ-1032, and pQ-1104 on neurological deficit and survival of rats after bilateral ligation of common carotid arteries. Preconditioning including moderate hypoxia and treatment with compound pQ-4 produced a neuroprotective effect and increased animal survival during the early (by 51%) and late (by 33.5%) periods of modeled ischemia and reduced neurological deficit (by 50% and 41%, respectively). Moreover, this combination of preconditioning factors prevented postischemic excessive activation of free radical oxidation in brain hemispheres and blood serum.

[MINERAL BONE DENSITY AND BODY COMPOSITION IN PARTICIPANTS IN EXPERIMENT MARS-500].

Investigations of the bone system and body composition in Mars-500 test-subjects (prior to and on completion of the experiment) involved dual-energy X-ray absorptiometry (DXA) using the HOLOGIC Delphy densitometer and the protocol performed to examine cosmonauts. Bone density of lumber vertebrae and femoral proximal epiphysis, and body composition were measured. Reliable changes in vertebral density found in 3 test-subjects displayed different trends from +2.6 to -2.4%. At the same time, the experiment decreased significantly mineral density of the femoral proximal epiphysis, including the neck, in all test-subjects. Four test-subjects had cranial mineralization increased by 5-9%, same as in some cosmonauts after space flight. All tests-subjects incurred adipose loss from 2 to 7 kg; one test-subject lost 20 kg, i.e. his adipose mass became three times less. Changes in lean mass (1-3 kg) typically were negative; as for changes in lean mass of extremities, they could be linked with adherence to one or another type of physical activity. Therefore, extended exposure to confinement may affect mineralization of some parts of the skeleton. Unlike real space missions and long-term bedrest studies conducted at the Institute of Biomedical Problems in the past, Mars-500 did not cause clinically significant mineral losses (osteoporosis, osteopenia), probably because of the absence of effects of microgravity.

[INFLUENCE OF COMBINED PHARMACOLOGICAL AND HYPOXIC PRECONDITIONING ON ANIMAL SURVIVAL AND FUNCTIONAL ACTIVITY OF CNS DURING MODEL CEREBRAL ISCHEMIA.]

The combined action of amthizole administration and hypoxia conditions on the survival of rats and the functional state of the central nervous system has been studied on a model of bilateral common carotid artery occlusion. It is established that this combined preconditioning produces cerebroprotective action, increases animal survival after surgery (estimated 72 h upon the onset of ischemia) by 38% (p = 0.029) in early and by 29% (p = 0.078) in late period of the ischemia modeling, reduces neurological deficiency by 55% (p = 0.006) in early and by 43 % (p = 0.028) in late period of the ischemia modeling, and decreases severity of behavioral changes in rats caused by cerebral ischemia in both periods of ischemia modeling.

[Promising directions of search for antihypoxants and targets of their action].

The modem notions about mechanisms of the organism adaptation to hypoxia are reviewed. Promising new directions in the search for effective medicinal agents with antihypoxant action are proposed. Probable targets for antihypoxant action, including mitochondrial ATP-dependent potassium channel (mito-KATP), mitochondrial megapore (mPTP), and hypoxia-inducible factor-1alfa (HIF-1alpha) are discussed.

[Influence of hypoxen on acetylsalicylic acid efficiency in acute inflammation].

Rats were treated by subplantar injections of 0.1 ml 1% carrageenan solution. In 3 hours, this led to the development of acute inflammatory reaction (swelling of legs, neutrophilic leukocytosis, increased erythrocyte sedimentation rate, activation of free-radical oxidation). Acetylsalicylic acid in a dose of 100 mg/kg reduced development of the inflammatory response. Hypoxen in a dose of 50 mg/kg potentiated the effect of acetylsalicylic acid. The injection of both hypoxen and acetylsalicylic acid before the injection of carrageenan produced a strong anti-inflammatory effect, which was manifested by a reliable decrease in all monitored signs of inflammation.

[Estimating the anti-inflammatory activity of drugs by changes in the agranulocyte/granulocyte index].

It is suggested to assess the anti-inflammatory activity using the ratio of the sums of agranulocytes and granulocytes. On the model of carrageenan-induced inflammation in the rat limbs, the anti-inflammatory activity of NSAIDs and their combinations with antihypoxants was characterized in terms of limb size, leukogram, and the proposed index of anti-inflammatory activity. A high anti-inflammatory activity was observed for a combination of hypoxen with diclofenac and acetylsalicylic acid and a combination of metaprot with diclofenac.

[Effect of a new triazinoindole derivative on the functional state of CNS in animals under normoxia and hypoxia conditions].

The influence of the new triazinoindole derivative encoded VM-606 on the individual behavior of rats in the open-field and elevated-plus-maze tests has been studied under normal conditions and after exposure to hypoxia with hypercapnia. It is established that VM-606 at a dose of 50 mg/kg under normoxia conditions reduces emotional anxiety, orientation-investigation activity, and mobility factor, while under hypoxic conditions this drug reduces the severity of behavioral changes in test animals. The experiments on mice showed that the compound studied potentiates the hypnotic effect of hexenal. It is suggested that VM-606 exhibits psychosedative and stress-protector properties, which play a certain role in its antihypoxic effect.

[Characteristics of local human skeleton reactions to microgravity and drug treatment of osteoporosis in clinic].

Analysis of the results of long-term investigations of bones in cosmonauts flown on the orbital station MIR and International space station (n = 80) was performed. Theoretically predicted (evolutionary predefined) change in mass of different skeleton bones was found to correlate (r = 0.904) with position relatively the Earth's gravity vector. Vector dependence of bone loss ensues from local specificity of expression of bone metabolism genes which reflects mechanic prehistory of skeleton structures in the evolution of Homo erectus. Genetic polymorphism is accountable for high individual variability of bone loss attested by the dependence of bone loss rate on polymorphism of certain bone metabolism markers. Parameters of one and the other orbital vehicle did not modulate individual-specific stability of the bone loss ratio in different segments of the skeleton. This fact is considered as a phenotype fingerprint of local metabolism in the form of a locus-unique spatial structure of distribution of noncollagenous proteins responsible for position regulation of endosteal metabolism. Drug treatment of osteoporosis (n = 107) evidences that recovery rate depends on bone location; the most likely reason is different effectiveness of local osteotrophic intervention into areas of bustling resorption.

[Interrelation of dynamics of blood lipids and bone mineral density in humans during 370-day bed rest].

Comparison of bone mineral density and fatty-acid blood content in 9 human subjects exposed to 370-d bed rest revealed correlation of the loss in femoral neck density with parameters of lipid exchange. On day-46 of BR, the absolute lipids content in erythrocyte membranes and blood serum decreased considerably (1.5-2 times) when compared with baseline data. At the end of the experiment, lipids content in serum, on the contrary, surpassed baseline values 2-3 times: however, it remained lowered in erythrocyte membranes of the control group till day-280 of BR. Arachidonic acid correlated with prostaglandins PGE2 and PGF2alpha involved in regulation of osteoclasts and osteoblasts activities. Correlation of decreases in femoral neck density and unsaturated fatty acids in blood serum and erythrocyte membranes varied with the human subjects.

[Biogenic stimulants of metabolism in articular cartilage].

The review considers issues of pharmacodynamics and clinical applications of drugs with the metabolic type of action, which stimulate regeneration and provide the protective action on articular cartilage in cases of osteoarthritis. Published data of the experimental and clinical trials of the main chondroprotective agents are analyzed.

[Analysis of polymorphism of bone metabolism genes and evaluation of the risk of osteopenia in cosmonauts].

Densitometry of cosmonauts following long-duration missions shows reduction of bone mineral density (BMD). On the average, post-flight BMD remains within the normal range and the broad variability of individual BMD values sometimes is qualified as local osteopenia. Individual reactions are typed by similarity of amount and rate of BMD loss. At present, analysis of functionally significant polymorphism of bone metabolism genes is the most effective instrument for diagnostics of susceptibility to osteopenia and osteoporosis. The investigation was aimed to analyze polymorphism of genes of vitamin-D and (VDR) and calcitonin (CALCR) receptors, and of collagen-1 alpha-1-chain (Col1a-1) in candidate cosmonauts and cosmonauts returned from 5 to 7-mo. missions. According to the results of analysis, in the majority of cosmonauts rapid BMD loss correlated with TT genotype by VDR gene but not with genotypes Tt and tt and associated with carriage of incomplete s-allele in the Col1a1 gene. Yet, in several instances high BMD loss rates were personified with carriers of VDR gene alleles (homo- and heterozygote states--tt and Tt) and heterozygote by Col1a1 gene (Ss).

[Investigation of mineral density and the bone structure following 105 day experiment in an isolated environment (MARS-105)].

Healthy volunteers' bone system investigation was performed before and after 105 days experiment in an isolated environment (MARS-105) using dual energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT). Volumetric bone mineral density (VBMD), bone mineral density (BMD), structural parameters of radius and tibia were evaluated. There were no significant BMD changes revealed in skeletal parts critical in terms of biomechanical properties. pQCT examination noted microarchitecture deterioration of radius that was reflected in decreasing of trabecular number and increasing of bone tissue inhomogeneity. Decreasing VBMD both cortical and trabecular bone were revealed for tibia. Unexpectedly, increasing oftrabecular number and decreasing of inhomogeneity were revealed for tibia. Experiment showed that only the complex investigation including DXA and pQCT measurements gives an idea about bone system changes under simulated experiment conditions.

[Comparative analysis of cosmonauts skeleton changes after space flights on orbital station Mir and international space station and possibilities of prognosis for interplanetary missions].

A summary of investigations results of human bone tissue changes in space flight on the orbital station (OS) Mir and international space station (ISS) using dual energy X-ray absorptiometry (DXA) is given. Results comparative analysis revealed an absence of significant differences in bone mass (BM) changes on the both OS. Theoretically expected BM loss was observed in bone trabecular structure of skeleton low part after space flight lasting 5-7 month. The BM losses are qualified in some cases as quicly developed but reversible osteopenia and generally interpreted as evidence of bone functional adaptation to the alterating mechanical loading. It was demonstrated the high individual variability BM loss amplitudes. Simultaneously was observed the individual pattern of BM loss distribution across different segments of skeleton after repetitive flights independently upon type of OS. In according with the above mentioned individual peculiarities it was impossible to establish the dependence of BM changes upon duration of space missions. Therefore we have not sufficiently data for calculation of probability to achive the critical demineralization level by the augmentation the space mission duration till 1.5-2 years. It is more less possibility of the bone quality changes prognosis, which in the aggregate with BM losses determines the bone fracture risk. It become clearly that DXA technology is unsuffitiently for this purpose. It is considered the main direction which may optimized the elaboration of the interplanetary project meaning the perfectly safe of skeleton mechanical function.

[Gastroprotective properties of mexidol and hypoxen].

Experimental damage in the stomach mucosa of test rats was modeled by acetylsalicylic acid (aspirin-induced ulcerogenesis). The number of ulcers and the total area of erosive injury in the mucous membrane were studied. Prophylactic treatment with mexidol and hypoxen in a daily dose of 50 mg/kg reduces the aspirin-induced damage of stomach mucosa. The gastroprotective properties of drugs are probably related to their antioxidant and antihypoxant effects.

[Effects of hypoxen on morphological and functional state of the liver under of exogenous intoxication conditions].

The effects of hypoxen on the metabolic processes in the liver tissue have been investigated on experimental animals (rats) with model tetrachloromethane (CCl4) induced toxic liver damage. It is established that the drug decreases the activity of transaminases and lactate dehydrogenase, the total bilirubin level in the blood serum, and the rate of free-radical lipid oxidation in the liver. These effects of hypoxen can be considered as manifestations of the hepatoprotective activity. The efficiency of the drug under conditions of CCl4 intoxication was confirmed by the results of a histological examination.

[NSAID-induced gastropathy and its prophylaxis].

Data on the frequency of NSAID-induced gastropathy, its pathogenesis, risk factors, and the principal ways of prevention are reviewed.