Brain-derived neurotrofic factor (BDNF) secretion of human mesenchymal stem cells isolated from bone marrow,endometrium and adipose tissue

The ability of mesenchymal stem cells (MSCs) to differentiate into neuronal lineage determines the potential of these cells as a substrate for a cell replacement therapy. In this paper we compare the neurogenic potential of the MSCs from different donors, isolated from the bone marrow (BMSC), subcutaneous adipose tissue (AD MSC) and menstrual blood (eMSC). It was established that the native eMCSs, BMSCs and AD MSCs express neuronal marker β-III-tubulin with a frequency of 90, 50 and 14%, respectively. Also we showed that the eMSCs have a high endogenous level of brain-derived neurotrophic factor (BDNF), whereas the BMSCs and the AD MSCs are characterized by low basal BDNF levels. An induction of neuronal differentiation in the studied MSCs using differentiation medium containing B27 and N2 supplements, 5-azacytidine, retinoic acid, IBMX and dbcAMP induced changes in the cells morphology, the increase of β-III-tubulin expression, and the appearance of neuronal markers GFAP, NF-H, NeuN and MAP2. During the differentiation the BDNF secretion was significantly enhanced in the BMSCs and decreased in the eMSCs cultures. However, no correlation between the basal and induced levels of the neuronal markers expression in the studied MSCs has been established.     

Generation of dopamine neurons from human embryonic stem cells in vitro

The aim of the study was to generate dopaminergic (DA) neurons from human embryonic stem cells (ESCs) in vitro. It was shown that human ESCs can be differentiated into DA neurons without co-culture with stromal cells. Terminal differentiation into DA neurons was reached by the successive application of noggin and bFGF growth factors and collagen and matrigel substrates for 3–4 weeks. The efficiency of differentiation was evaluated by the number of colonies with cells that express tyrosine hydroxylase (TH), a DA neuron marker, and by the number of TH-positive cells in cell suspension estimated by flow cytometry. No cells with pluripotent markers were detected in DA-differentiated cultures. The lack of pluripotent cells in population at the final stage of differentiation is encouraging and shows that this protocol of human ESC differentiation may be applied to generate DA neurons for their transplantation into the animals modeling neurodegenative (Parkinson) disease without the risk of tumor growth.     

Carcinogenic aging

In ours and other studies, data have been obtained testifying to the fact that, under the action of various classes of chemical carcinogenic agents (polycyclic aromatic hydrocarbons, nitrous compouds, aromatic amines), other mutagens, ionizing radiation, extremely low frequency (50 Hz), electromagnetic fields (EMFs), constant illumination, and smoking, in the basic homeostatic systems of an organism (nervous, endocrine, immune, and energy homeostasis) premature hormonal, and metabolic shifts occur similar to those arising during physiological aging. These shifts create favorable conditions for the promotion and progression stages of carcinogenesis. The use of genetically modified animals (mutant, transgenic, or knockout) opens new possibilities for analyzing the role of individual genes in the interrelationships between processes of natural and accelerated, by environmental factors, aging. For genetically modified mice with phenotypic signs of accelerated aging, as a rule, the frequency of new-growth development increases, then for animals with decelerated aging, an increase in the latent period of tumor development and/or a decrease in the frequency of their appearance is noted. The application of geroprotectors under conditions of increased risk of accelerated aging resulting genetically or from adverse environmental factors (carcinogens, mutagens, peculiarities in diet) can be a first line prevention against cancer.     

Relationship between genome size and organismal complexity in the lineage leading from prokaryotes to mammals

The lack of a strict relationship between genome size and organismal complexity (level of organization) is largely due to size variability of the facultative part of the genome. However, there is a direct relationship between the level of organization and the minimal genome size (MGS) in the lineage leading from prokaryotes to mammals, in which the tendency towards increasing complexity is especially clear. The dynamics of MGS in this lineage can be adequately described by the model of hyperexponential growth. This implies the existence of nonlinear positive feedbacks that account for the acceleration of MGS growth. The nature of these feedbacks is discussed, including the formation of new genes by means of recombination of the fragments of existing genes, formation of “niches” for new genes in the course of evolution of gene networks, and the expansion of regulatory regions. Hyperexponential growth of different variables related to the level of organization of the biosphere and society (biodiversity, MGS, size and complexity of organisms, world population, technological development, urbanization, etc.) suggests that the evolution of the biosphere and humanity in the direction of increasing complexity is a self-accelerating (autocatalytic) process.     

Neirokhimiya 1999

Abstract List

Neirokhimiya 1999     

Evolutionary regularities of somatic polyploidy in salivary glands of the Gastropod molluscs. II. Subclass Pectinibranchia: order Anisorbranchia

Salivary glands of 5 species of gastropod molluscs of the order Anisobranchia, the most ancient order within the subclass Pectinibranchia, have been investigated by histological and cytochemical methods, including DNA cytophotometry. Glandular cells of the following types were recognized: granular cells (with glycoproteid granular inclusions), mucocytes-I (including sulfatic acid mucopolysaccharides), mucocytes-II (including neutral and acid polysaccharides and proteins), and epithelial ciliated cells. All the described cell types are considered to be independent and their morphofunctional characteristics coincide with those of salivary gland cells of the gastropod molluscs of subclasses Cyclobranchia and Scutibranchia. It has been shown that somatic polyploidy in salivary glands in the Anisobranchia molluscs, likely as in those of other Archaeogastropoda (Cyclobranchia and Scutibranchia), is actually absent.     

Morphofunctional parameters of the nucleoli during development of polyploid nutrient cells of gonads from the snail Succinea lauta

Ag-protein contents, integral area and number of nucleoli in polyploidizing nuclei of gonadal nutrient cells of the snail Succinea lauta were estimated on the squashed preparations by means of morphometry and cytophotometry. 8 NORs of different size were found in haploid chromosome set of prophase spermatocytes (n = 22), but usually 1-2 nucleoli per 2c DNA are present in the nutrient cell nuclei. During genome multiplication from 2c to 32c-64c the Ag-proteins content of nucleoli increased proportionally to gene dosage, but irregularly: before 8c-level the coefficient of increasing in each endocycle was more than 2; from 8c to 16c it was 2; after 16c-level it usually decreased to 1.6-1.3. This dynamics reflects the effects of several factors on nucleolar activity: endomitotic polyploidy (gene dosage effect), differentiation and rhythmic functioning of tissue. Increasing indexes of integral area and the number of nucleoli during polyploidization were significantly less, than increasing index of Ag-proteins. The lag of nucleolar area for 4 cycles (2c-32c) was 32%, and number of nucleoli per diploid set decreased from 2 to 1. It may be due to NOR aggregation corresponding chromosomes. The photometric index of Ag-protein content more adequately reflects in the nucleolar activity during development and functioning of tissues.     

Cell technologies and the development of skin substitutes

Large skin lesions might be of different cause and sometime resistant to the conventional and surgical treatment. For many years, skin grafting used to serve one of the most important methods to treat large and deep skin lesions. However, a limited availability of the substrate for transplantation restricts wider application of the approach. Utilization of wound covers and skin replacements of various types (including synthetic, biological and biosynthetic ones) provides an alternative. Skin substitutes--biosynthetic covers of the complex structure--constitute the most important niche in a wide spectrum of wound covers developed and actively utilized by today. Cell substrates used in the former include dermal fibroblasts, neonatal foreskin fibroblasts and keratinocytes. In the current review, key properties of the modern skin substitutes, structure features of the most widespread types. and principle of the work with the particular cell types are analyzed. Comparative analysis of the efficiency of wound covers is provided.     

Light pollution, reproductive function and cancer risk

At present, light pollution (exposure to light-at-night) both in the form of occupational exposure during night work and as a personal choice and life style, is experienced by numerous night-active members of our society. Disruption of the circadian rhythms induced by light pollution has been associated with cancer in humans. There are epidemiological evidences of increased breast and colon cancer risk in shift workers. An inhibition of the pineal gland function with exposure to the constant light (LL) regimen promoted carcinogenesis whereas the light deprivation inhibits the carcinogenesis. Treatment with pineal indole hormone melatonin inhibits carcinogenesis in pinealectomized rats or animals kept at the standard light/dark regimen (LD) or at the LL regimen. These observations might lead to use melatonin for cancer prevention in groups of humans at risk of light pollution.