[The interactions along the microbiota-gut-brain axis in the regulation of circadian rhythms, sleep mechanisms and disorders]. / Rol' vzaimosvyazei po osi mozg­kishechnik­mikrobiom v regulyatsii tsirkadiannykh ritmov, mekhanizmakh sna i ikh narushenii.

The bidirectional relationship between cerebral structures and the gastrointestinal tract involving the microbiota embraces the scientific concept of the microbiota-gut-brain axis. The gut microbiome plays an important role in many physiological and biochemical processes of the human body, in the immune response and maintenance of homeostasis, as well as in the regulation of circadian rhythms. There is a relationship between the higher prevalence of a number of neurological disorders, sleep disorders and changes in the intestinal microbiota, which actualizes the study of the complex mechanisms of such correlation for the development of new treatment and prevention strategies. Environmental factors associated with excessive light exposure can aggravate the gut dysbiosis of intestinal microflora, and as a result, lead to sleep disturbances. This review examines the integrative mechanisms of sleep regulation associated with the gut microbiota (the role of neurotransmitters, short-chain fatty acids, unconjugated bile acids, bacterial cell wall components, cytokines). Taking into account the influence of gut dysbiosis as a risk factor in the development of various diseases, the authors systematize key aspects and modern scientific data on the importance of microflora balance to ensure optimal interaction along the microbiota-gut-brain axis in the context of the regulatory role of the sleep-wake cycle and its disorders.

[The significance of glymphatic pathway in the relationship between the sleep-wake cycle and neurodegenerative diseases]. / Rol' glimfaticheskogo klirensa v mekhanizmakh svyazi tsikla «son­bodrstvovanie¼ i razvitiya neirodegenerativnykh protsessov.

Selective and progressive death of neurons is a characteristic feature of the process of neurodegeneration and leads to corresponding neuronal dysfunctions. Neurodegenerative diseases represent a heterogeneous group of clinically distinct disorders with similar molecular mechanisms of pathogenesis. They are based on the processes of abnormal aggregation of proteins, the formation of fibrillary insoluble structures and their deposition in the form of histopathological inclusions in the tissues of the nervous system. Disturbance of homeostatic functions that regulate neuronal ion and energy metabolism, biosynthesis and degradation of proteins and nucleotides, chronic hypoxia and the penetration of toxic and inflammatory substances into the brain from the bloodstream not only cause metabolic changes associated with age and disorders in the sleep-wake cycle, but also contribute to the development of neurodegenerative diseases. In animal studies, clearance pathways have been identified in which solutes and specific tracers are excreted perivascular into the meningeal lymphatics. The glymphatic pathway promotes the removal of metabolites, including Aß amyloid and tau protein, from the parenchymal extracellular space of the brain. The glymphatic system is discussed to be more efficient during natural sleep, and fluid dynamics through this pathway exhibit daily fluctuations and are under circadian control. This review systematizes the key aspects and scientific data of recent studies on the role of the glymphatic pathway and astroglial AQP-4 as its main determinant in maintaining homeostatic fluid circulation in the brain in normal and pathological conditions, in particular in relation to the regulatory role of the sleep-wake cycle and in development of neurodegeneration.

[The significance of the glymphatic pathway in the relationship between the sleep-wake cycle and neurodegenerative diseases]. / Rol' glimfaticheskogo klirensa v mekhanizmakh vzaimosvyazi tsikla «son­bodrstvovanie¼ i razvitiya neirodegenerativnykh protsessov.

Selective and progressive death of neurons is a characteristic feature of the process of neurodegeneration and leads to corresponding neuronal dysfunctions. Neurodegenerative diseases represent a heterogeneous group of clinically distinct disorders with similar molecular mechanisms of pathogenesis. They are based on the processes of abnormal aggregation of proteins, the formation of fibrillary insoluble structures and their deposition in the form of histopathological inclusions in the tissues of the nervous system. Disturbance of homeostatic functions that regulate neuronal ion and energy metabolism, biosynthesis and degradation of proteins and nucleotides, chronic hypoxia and the penetration of toxic and inflammatory substances into the brain from the bloodstream not only cause metabolic changes associated with age and disorders in the sleep-wake cycle, but also contribute to the development of neurodegenerative diseases. In animal studies, clearance pathways have been identified in which solutes and specific tracers are excreted perivascular into the meningeal lymphatics. The glymphatic pathway promotes the removal of metabolites, including Aß amyloid and tau protein, from the parenchymal extracellular space of the brain. The glymphatic system is discussed to be more efficient during natural sleep, and fluid dynamics through this pathway exhibit daily fluctuations and are under circadian control. This review systematizes the key aspects and the data of recent research on the role of the glymphatic pathway and astroglial AQP-4 as its main determinant in maintaining homeostatic fluid circulation in the brain in normal and pathological conditions, in particular in relation to the regulatory role of the sleep-wake cycle and in development of neurodegeneration.

[Neuromuscular stimulation in conditions of vibrational physical activity for the prevention of osteoporosis]. / Neiromyshechnaya stimulyatsiya v usloviyakh vibratsionnoi fizicheskoi nagruzki dlya profilaktiki osteoporoza.

The review discusses the modern possibilities of non-drug rehabilitation of patients with osteoporosis. Osteopenia (osteoporosis) and osteoporosis-associated bone fractures are a global public health problem, and an intensive search is undergoing for new methods of treatment, prevention, diagnosis and screening of this disease. Innovative technologies for influencing bone remodeling using vibration training seem to be an effective method that allows you to simultaneously positively affect maintaining bone density, increasing muscle strength and improving coordination, especially in elderly patients. The evolution of study of the effects of intense neuromuscular stimulation under accelerated physical exertion, which began with fundamental work on experimental animals, now includes numerous clinical studies. Vibrational physical activity is one of the methods of biomechanical stimulation, which is considered as an innovative method in the field of rehabilitation and physiotherapy. The physiological basis of this effect is intensive neuromuscular stimulation, which causes a reflex reaction of skeletal muscles. This scientific review describes the results of both monotherapy and combined methods of exposure to vibrational stimulation using modern pharmacotherapy. Attention is focused on the positions of importance in the design of the study and the planning of rehabilitation programs of uniformly accelerated training.

Integration of the Proprioceptive and Central Inspiratory Inhibitory Afferent Inputs by Pontine Noradrenergic A5 Neurons in Rats.

Inhibitory afferent inputs to pontine A5 noradrenergic neurons (A5 NN) are not known, except partial baroreceptor input. In spontaneously breathing pentobarbital-anesthetized rats, we registered 35 A5 NN that were activated by hypoxia (100% N2, 10 sec) by more than 5 times in comparison with the background. Cooling of retrotrapezoid nucleus (15°C, 6 sec) completely blocked the motor inspiratory output and A5 NN discharge frequency increased (23/23) by more than 7 times in comparison with the background values. The beginning of A5 NN activation coincided with cessation of inspiratory activity. Short-term passive stretching of the shin muscles (1 sec, 100 g) caused BP drop and complete inhibition of A5 NN (12/12) activated by hypoxia. Inhibitory afferent inputs from proprioceptors and central inspiratory neurons that can limit A5 NN activity were demonstrated.

[Recent medical techniques for peripheral nerve repair: nerve guidance conduits update].

The review deals with recent medical methods of reconstruction of peripheral nerve injuries, especially using the technology of nerve guidance conduits (NGCs), as well as scientific and applied prospects of further development of clinical and technical research in this area. In neurosurgery established techniques for the treatment of peripheral nerve injures include the matching and suturing of severed nerve fibers (however, it is important to avoid tension in gaps for effective regeneration of the nerve fiber), as well as allo/autologous nerve grafting for larger gaps (gold standard of repair). Unfortunately, this treatment is not always feasible in a number of clinical situations, has drawbacks and is associated with a potential risk of postoperative complications; in particular applying of donor transplants is complicated immunological incompatibility reactions. The use of implantable artificial tunneling device known as a nerve guidance conduit is an alternative method of reconstruction, contributing to the physiological regeneration of nerve fiber. The article describes technical engineering constructions - including by using various non- and biomaterials, liquid metals, light/laser, methods of electrospinning and microstereolithography - which are either commercially available or pre-tested and clinical studies detailing outcomes and reconstructive options. The review emphasizes that the further development of scientific research in the field of new materials and polymers, as well as techniques for the preparation and implantation of nerve conduits and their subsequent practical assessment is necessary for clinical medicine and rehabilitation.

[Whole body vibration (acceleration) training increases bone mineral density and serum levels of osteocalcin in elderly women].

Hip bone mineral density (BMD) and serum markers of bone turnover during drug (antiresorptic medicaments) and non-drug (acceleration training) therapy in elderly women suffering from postmenopausal osteoporosis has been investigated. The hip BMD measured in elderly women after a 24-week antiresorptic therapy (alendronate) and increased by 2.01%. 24-week acceleration training resulted in 1.56% benefit in hip BMD and also serum levels of osteocalcin (+50%, p < 0.05) significantly increased in postmenopausal women. We have determined that the osteogenic effect of acceleration training is mediated by stimulated bone formation. Our findings suggest that whole body vibration (acceleration) training may be a beneficial technique to prevent and treat osteoporosis.

[Vibrational physical exercises as the rehabilitation in gerontology].

Vibration biomechanical stimulation as the physiological basis of vibration physical exercises (whole body vibration) causes reflecting muscle contractions like tonic vibration reflex. This type of intervention leads to high intensive stimulation of proprioceptors as called muscle spindles which result in alteration in parameters of activity and developments of human physiological functions. This type of training has broad positive influence on organism. Acceleration physical exercises improve muscle performance, flexibility, nervous function, significantly increase bone mineral density, physiological secretion of anabolic hormones, growth and anti-aging factors; normalize/decrease cortisol as anti-stress effect and are beneficial for balance and mobility as well. It is showed acceleration training caused by vibration stimulus is beneficial for people suffering from osteoporosis and obesity, for rehabilitation of nervous and motor function in patients with Parkinson's disease, multiple sclerosis and stroke.