Mesenchymal stem (stromal) cells (MSCs) are self-renewing, cultured adult stem cells which secrete a complex set of multiple soluble biologically active molecules such as chemokines, and cytokines, cell adhesion molecules, lipid mediators, interleukins (IL), growth factors (GFs), hormones, micro RNAs (miRNAs), long non-coding RNAs (lncRNAs), messenger RNAs (mRNAs), exosomes, as well as microvesicles, the secretome. MSCs of various origin, including adipose-derived stem cells (ASCs), bone marrow derived mesenchymal stem cells (BM-MSCs), human uterine cervical stem cells (hUCESCs), may be good candidates for obtaining secretome-derived products. Different population of MSCs can secret different factors which could have anti-inflammatory, anti-apoptotic, anti-fibrotic activities, a neuroprotective effect, could improve bone, muscle, liver regeneration and wound healing. Therefore, the paracrine activity of conditioned medium obtained when cultivating MSCs, due to a plethora of bioactive factors, was assumed to have the most prominent cell-free therapeutic impact and can serve as a better option in the field of regenerative medicine in future.

Structure and synthesis of Erythropoietin: Erythropoietin (EPO) is a glycoprotein hormone.Recombinant Erythropoietin (Epoetin): Human recombinant erythropoietin is characterised as a factor which stimulates differentiation and proliferation of erythroid precursor cells, and as a tissue protective factor.Anti-ischemic effects of recombinant Erythropoietin: Erythropoietin is one of the most perspective humoral agents which are involved in the preconditioning phenomenon.Erythropoietin receptors and signal transduction pathways: Erythropoietin effects on cells through their interconnection with erythropoietin receptors, which triggers complex intracellular signal cascades, such as JAK2/STAT signaling pathway, phosphatidylinositol 3-kinase (PI3K), protein kinase C, mitogen-activated protein kinase (MAPK), and nuclear factor (NF)-κB signaling pathways.Mechanisms of the effect of Erythropoietin on hematopoietic and non-hematopoietic cells and tissues: In addition to regulation of haemopoiesis, erythropoietin mediates bone formation as it has an effect on hematopoietic stem cells and osteoblastic niche, and this illustrates connection between the processes of haematopoiesis and osteopoiesis which take place in the red bone marrow.The effect of Erythropoietin on mesenchymal stem cells and process of bone tissue formation: Erythropoietin promotes mesenchymal stem cells proliferation, migration and differentiation in osteogenic direction. The evidence of which is expression of bone phenotype by cells under the influence of EPO, including activation of bone specific transcription factors Runx2, osteocalcin and bone sialoprotein.Conclusion: Erythropoietin has a pleiotropic effect on various types of cells and tissues. But the mechanisms which are involved in the process of bone tissue restoration via erythropoietin are still poorly understood.

We studied the expression of transcription factors RUNX2 and Osterix after addition of a concentrate of osteogenic-conditioned medium to the culture medium for osteogenic differentiation of mesenchymal stem cells (MSC). The obtained concentrate of osteogenic-conditioned medium containing a complex of bioactive substances with a molecular weight >10 kDa provided MSC differentiation into osteoblasts, which was confirmed by high level of expression of transcription factors RUNX2 and Osterix in comparison with the negative control. The highest expression of transcription factor Osterix was revealed on day 14 of MSC culturing in the presence of osteogenic supplement StemPro (positive control) and the studied concentrate of osteogenic-conditioned medium.

The 40-60-year-old patients with knee OA more commonly develop symptoms of chronic venous insufficiency than their healthy peers. Although obesity is a risk factor for both diseases, there is an independent association between knee OA and lower extremity VVD.

The osteoinductive characteristics of hydroxylapatite-based coating with different physicochemical characteristics were studied. The formation of the bone tissue on the studied types of the implant coating differed by the pattern and rate of formation of structural elements of the bone. Clear-cut phase-wise osteogenesis was seen on combined calcium phosphate coating: intense formation of the fibrous interstitial substance (due to cellular structure of hydroxylapatite) and slow maturing of cell elements. Bilayer composite coating provided (during the same period) the formation of more mature connective tissue. This phenomenon can be explained by better bioavailability of the coating material. The properties of combined calcium phosphate coating can be evaluated as mainly osteoconductive, while those of bilayer composite coating as osteoinductive.

Волгоградский государственный медицинский университет, кафедра физического воспитания и здоровья, Волгоградская государственная академия физической культуры, кафедра анатомии и физиологии Проведено исследование гендерных различий в интегральных показателях уровня здоровья и адаптационного потенциала у студентов вуза физкультурного профиля. Сделан вывод о том, что уровень здоровья у девушек в среднем выше, чем у юношей, но, вместе с тем, адаптационные резервы у них несколько ниже, что может приводить к срыву адаптации, несмотря на более высокие исходные показатели уровня здоровья.

We studied the influence of the characteristics of oxide porous coatings on osteogenesis and integration of new bone tissue and titanium implant surface in the ectopic osteogenesis test. Implants with coating with pore size 2-20 μ exhibit better osteogenic and osteoconductive characteristics than implants with homogenous surface and smooth relief (pore size 0.5-5.0 μ). Physical characteristics of the surface of the material along with chemical composition of the coating are essential for the formation of bone tissue and its integration with the implant.

Introduction: The article describes a new method of tissue engineering, which is based on the use of three-dimensional multicellular constructs consisting of stem cells that mimic the native tissue in vivo – organoids. 3D cell cultures: The currently existing model systems of three-dimensional cultures are described. Characteristics of organoids and strategies for their culturing: The main approaches to the fabrication of 3D cell constructs using pluripotent (embryonic and induced) stem cells or adult stem cells are described. Brain organoids (Cerebral organoids): Organoids of the brain, which are used to study the development of the human brain, are characterized, with the description of biology of generating region-specific cerebral organoids. Lung organoids: Approaches to the generation of lung organoids are described, by means of pluripotent stem cells and lung tissue cell lines. Liver organoids: The features of differentiation of stem cells into hepatocyte-like cells and the creation of 3D hepatic organoids are characterized. Intestinal organoids: The formation of small intestine organoids from stem cells is described. Osteochondral organoids: Fabrication of osteochondral organoids is characterised. Use of organoids as test systems for drugs screening: The information on drug screening using organoids is provided. Using organoids to model infectious diseases and study adaptive responses of microorganisms when interacting with the host: The use of organoids for modeling infectious diseases and studying the adaptive responses of microorganisms when interacting with the host organism is described. Conclusion: The creation of three-dimensional cell structures that reproduce the structural and functional characteristics of tissue in vivo, makes it possible to study the biology of the body’s development, the features of intercellular interactions, screening drugs and co-cultivating with viruses, bacteria and parasites.