Epigenetic Memory in Mammals

Epigenetic information can be passed on from one generation to another via DNA methylation, histone modifications, and changes in small RNAs, a process called epigenetic memory. During a mammal’s lifecycle epigenetic reprogramming, or the resetting of most epigenetic marks, occurs twice. The first instance of reprogramming occurs in primordial germ cells and the second occurs following fertilization. These processes may be both passive and active. In order for epigenetic inheritance to occur the epigenetic modifications must be able to escape reprogramming. There are several examples supporting this non-Mendelian mechanism of inheritance including the prepacking of early developmental genes in histones instead of protamines in sperm, genomic imprinting via methylation marks, the retention of CenH3 in mammalian sperm and the inheritance of piwi-associated interfering RNAs. The ability of mammals to pass on epigenetic information to their progeny provides clear evidence that inheritance is not restricted to DNA sequence and epigenetics plays a key role in producing viable offspring

Epigenetic Modifications during Angiosperm Gametogenesis

Angiosperms do not contain a distinct germline, but rather develop gametes from gametophyte initials that undergo cell division. These gametes contain cells that give rise to an endosperm and the embryo. DNA methylation is decreased in the vegetative nucleus (VN) and central cell nuclei (CCN) resulting in expression of transposable elements (TEs). It is thought that the siRNAs produced in response to TE expression are able to travel to the sperm cells and egg cells (EC) from VN and CCN, respectively, in order to enforce silencing there. Demethylation during gametogenesis helps ensure that even newly integrated TEs are expressed and therefore silenced by the resulting siRNA production. A final form of epigenetic control is modification of histones, which includes accumulation of the H3 variant HTR10 in mature sperm that is then completely replaced following fertilization. In females, the histone isoforms present in the EC and CCN differ, potentially helping to differentiate the two components during gametogenesis

Induction and persistence of radiation-induced DNA damage is more pronounced in young animals than in old animals

Younger individuals are more prone to develop cancer upon ionizing radiation (IR) exposure. Radiation-induced tumors are associated with inefficient repair of IR-induced DNA damage and genome instability. Phosphorylation of histone H2AX (γ-H2AX) is the initial event in repair of IR-induced DNA damage on the chromatin flanking the DNA strand breaks. This step is crucially important for the repair of DNA strand breaks and for the maintenance of genome stability. We studied the molecular underpinnings of the age-related IR effects using an animal model. By assaying for IR-induced γ-H2AX foci we analyzed the induction and repair of the DNA strand breaks in spleen, thymus, liver, lung, kidney, cerebellum, hippocampus, frontal cortex and olfactory bulb of 7, 14, 24, 30 and 45 days old male and female mice as a function of age. We demonstrate that tissues of younger animals are much more susceptible to IR-induced DNA damage. Younger animals exhibited higher levels of γ-H2AX formation which partially correlated with cellular proliferation and expression of DNA repair proteins. Induction and persistence of γ-H2AX foci was the highest in lymphoid organs (thymus and spleen) of 7 and 14 day old mice. The lowest focal induction was seen in lung and brain of young animals. The mechanisms of cell and tissue-specificity of in vivo IR responses need to be further dissected. This study provides a roadmap for the future analyses of DNA damage and repair induction in young individuals

Uric acid, neuroendocrine-immune complex and metabolism: relationships

Background. During the implementation of the project "Physiological activity of uric acid", our group discovered four variants of the combination of levels of uricemia and uricosuria in patients with chronic pyelonephritis in the remission phase, which are accompanied by characteristic constellations of parameters of the central and autonomic nervous, endocrine, and immune systems, as well as the exchange of nitrogenous metabolites and electrolytes, the levels of which correlate with uricemia and/or uricosuria. The aim of this study is to clarify the relationship between parameters of uric acid exchange and neuroendocrine-immune complex as well as other metabolites. Materials and methods. Under an observations were 34 males (23-70 years) and 10 females (33-76 years) with chronic pyelonephritis in the phase of remission. The main object of the study was serum and urine levels of uric acid. Other metabolic, endocrine and immune parameters were determined in the same blood and urine samples. In addition, EEG and HRV was recorded almost synchronously. Results. Among all registered parameters, 28 were identified as characteristic of the four variants of uric acid metabolism. The discriminant model includes, in addition to uricosuria and uricemia by definition, 10 neuroendocrine, 5 immune, and 6 metabolic parameters, as well as bacteriuria, Bifidobacteria of feces, entropy of immunocytogram and Popovych’s leukocytogram strain index. According to the results of the canonical correlation analysis, it was established that balneotherapy-induced concomitant changes in uricosuria and uricemia positively determine changes in, first, the PSD of the theta-rhythm in the T3 locus and beta-rhythm in the O2 locus aa well as HRV-markers of vagal tone and sympatho-vagal balance; secondly – diuresis and excretion of urea, magnesium, sodium, phosphates, calcium, potassium and chloride, as well as calciumemia and magnesiumemia; thirdly – serum IgG and CIC. Instead, changes in cortisolemia and testosteroneemia as well as TNF-alpha and the intensity of Staph. aureus phagocytosis are subject to negative determination. In general, the rate of uric acid determination of the dynamics of the listed parameters of the body is 96%. Conclusion. The uric acid molecule, as a structural analog of methylxanthines and adenosine, exerts effects on neurons, endocrinocytes, and immunocytes, presumably through their adenosine receptors, and the metabolic effects of uric acid are the consequences of its neuro-endocrine effects

Transgenic plants as sensors of environmental pollution genotoxicity

Open accessRapid technological development is inevitably associated with many environmental problems which primarily include pollution of soil, water and air. In many cases, the presence of contamination is difficult to assess. It is even more difficult to evaluate its potential danger to the environment and humans. Despite the existence of several whole organism-based and cell-based models of sensing pollution and evaluation of toxicity and mutagenicity, there is no ideal system that allows one to make a quick and cheap assessment. In this respect, transgenic organisms that can be intentionally altered to be more sensitive to particular pollutants are especially promising. Transgenic plants represent an ideal system, since they can be grown at the site of pollution or potentially dangerous sites. Plants are ethically more acceptable and esthetically more appealing than animals as sensors of environmental pollution. In this review, we will discuss various transgenic plant-based models that have been successfully used for biomonitoring genotoxic pollutants. We will also discuss the benefits and potential drawbacks of these systems and describe some novel ideas for the future generation of efficient transgenic phytosensors.Ye

The institute of counter-security as a novelty of the reform of civil procedure law of Ukraine

The article is dedicated to investigation of counter-security as a novelty of the reform of Ukrainian civil procedure legislation. The analysis of rules of the current procedural legislation on counter-security as a novelty of the civil process in Ukraine was made in the article. The determination of features of the institute of counter-security in the mechanism of civil proceedings was given. The role of counter-security in the civil process was identified. The conclusion was drawn that through the institute of counter-security, the principle of equality of parties is ensured, which is manifested in the equal assignment of the defendant to such procedural rights which are effectively identical to the rights of the plaintiff. Therefore, the defendant was granted effective protection against the claim by virtue of the new institute. It is stated that the counter-security should be seen as a way of preventing the plaintiff's abuse of procedural rights and offsetting the potential consequences. The introduction of counter-security is a clear step forward to European standards of quality and efficiency in the administration of justice, however, by examining civil procedural law and jurisprudence, the conclusion was made that the institution is not regulated at this stage of its establishment and application

Role of the lipid peroxidation in immunomodulating effects of the nitrogenous metabolites in rats

Background. We have previously shown that nitrogenous metabolites have immunomodulatory effects, but the question of mediators of the immunomodulation remains open. We hypothesized the mediating role of mediators of the autonomic nervous system and adaptation hormones as well as reactive oxygen species. Mediating role in the immunomodulation of neuroendocrine factors is analyzed in a previous article. The aim of this study is to analyze the relationships between the parameters of nitrogenous metabolites and lipid peroxidation as well as between latter and immune parameters subordinate modulations by nitrogenous metabolites. Material and methods. Experiment was performed on 60 healthy female Wistar rats. The plasma level and urinary excretion of the nitrogenous metabolites as well as parameters of lipid peroxidation (diene conjugates, malonic dyaldehid, superoxide dismutase, catalase) and neuroendocrine-immune complex were determined. Results. According to the canonical correlation analysis, the constellation of nitrogenous metabolites determines the state of lipid peroxidation by 38,8%. The latter, in turn, determines the constellation of immune parameters (subject to modulation by nitrogenous metabolites) by 61,4%. On the other hand, the coefficient of determination between nitrogenous metabolites and neuroendocrine parameters is 71,5%, and between the latter and immune status – 89,6%. Taken together, neuroendocrine parameters and lipid peroxidation parameters determine the pool of immune parameters subject to modulation by nitrogenous metabolites by 96,7%. It was previously shown that the coefficient of determination between nitrogenous metabolites and a number of immune parameters is 95,8%. Conclusion. The obtained results, taken together with the previous ones, prove that uric acid, bilirubin, urea and creatinine realize their immunomodulatory effects both directly through receptors of immunocytes (aryl hydrocarbon, adenosine and TL) and with the participation of mediators of autonomic nervous and endocrine systems and lipid peroxidation