CD-1 mice females recognize male reproductive success via volatile organic compounds in urine.

Sexual selection is considered as one of the leading factors of evolutionary development. In the conditions of incessant competition, specialized methods of attracting individuals of the opposite sex as well as criteria for assessing the quality of a sexual partner have been formed. In order for animals to rely on signaling from sexual partners, the signal must reflect the morpho-physiological status of animals. A high reproductive efficiency of male mice is a good advantage for mate selection and thus must be somehow demonstrated to potential mates. The aim of our study was to find out if male mice could demonstrate their reproductive efficiency through urine volatile organic compounds. The experiment implies cohabiting one male with two mature females for 6 days. The reproductive success of the male was assessed by the presence or absence of pregnant females. At the same time, naive females, who did not participate in reproduction, assessed the urine of the successful males as more attractive, which was expressed in shorter Latency time of sniffs in the Olfactory test. Using a rapid headspace GC/MS analysis, we have found volatile organic compounds (VOCs) in male urine that correlated with female behavior. It turned out that these substances are derivatives of mouse pheromone 6-hydroxy-6-methyl-3-heptanone. The amplitude of peaks corresponding to this pheromone correlated with the testosterone level in blood and the weight of preputial glands. The amplitude of peaks increased in males after mating with whom the females turned out to be pregnant. It is important to note that body weight, weight of testes, weight of seminal vesicles, weight of preputial glands, and plasma testosterone level alone are not reliable indicators of male reproductive success. Thus, the content of the pheromone 6-hydroxy-6-methyl-3-heptanone in the urine of males can serve as a good predictor of the quality of the male as a sexual partner for female CD-1 mice.

Body composition as an indicator of metabolic changes in mice obtained by in vitro fertilization.

To identify body systems subject to epigenetic transformation during in vitro fertilization (IVF), comparative morphological and functional studies were performed on sexually mature offspring of outbred CD1 mice, specific-pathogen-free (SPF), obtained by IVF (experiment) and natural conception (control). The studies included assessment of age-related changes in body weight and composition, energy intake and expenditure, and glucose homeostasis. To level the effects caused by the different number of newborns in the control and in the experiment, the size of the fed litters was halved in the control females. Males obtained using the IVF procedure were superior in body weight compared to control males in all age groups. As was shown by analysis of variance with experiment/control factors, gender, age (7, 10 and 20 weeks), the IVF procedure had a statistically significant and unidirectional effect on body composition. At the same time, IVF offspring outperformed control individuals in relative fat content, but were behind in terms of lean mass. The effect of the interaction of factors was not statistically significant. IVF offspring of both sexes had higher fat to lean mass ratios (FLR). Since adipose tissue contributes significantly less to total energy intake compared to muscle, the main component of lean mass, it is not surprising that at the same level of IVF locomotor activity offspring consumed less food than controls. When converted to one gram of body weight, this difference reached 19 %. One of the consequences of reduced utilization of IVF energy substrates by offspring is a decrease in their tolerance to glucose loading. The integral criterion for the effectiveness of restoring the initial glucose level is the area under the curve (AUC), the value of which was 2.5 (males) and 3.2 (females) times higher in IVF offspring compared to the corresponding control. Thus, the totality of our original and literature data shows an increase in the risk of metabolic disorders in IVF offspring, which is confirmed by epidemiological studies of a relatively young cohort of people born using assisted reproductive technologies.

Generation of donor organs in chimeric animals via blastocyst complementation.

The lack of organs for transplantation is an important problem in medicine today. The growth of organs in chimeric animals may be the solution of this. The proposed technology is the interspecific blastocyst complementation method in combination with genomic editing for obtaining "free niches" and pluripotent stem cell production methods. The CRISPR/Cas9 method allows the so-called "free niches" to be obtained for blastocyst complementation. The technologies of producing induced pluripotent stem cells give us the opportunity to obtain human donor cells capable of populating a "free niche". Taken together, these technologies allow interspecific blastocyst complementation between humans and other animals, which makes it possible in the future to grow human organs for transplantations inside chimeric animals. However, in practice, in order to achieve successful interspecific blastocyst complementation, it is necessary to solve a number of problems: to improve methods for producing "chimeric competent" cells, to overcome specific interspecific barriers, to select compatible cell developmental stages for injection and the corresponding developmental stage of the host embryo, to prevent apoptosis of donor cells and to achieve effective proliferation of the human donor cells in the host animal. Also, it is very important to analyze the ethical aspects related to developing technologies of chimeric organisms with the participation of human cells. Today, many researchers are trying to solve these problems and also to establish new approaches in the creation of interspecific chimeric organisms in order to grow human organs for transplantation. In the present review we described the historical stages of the development of the blastocyst complementation method, examined in detail the technologies that underlie modern blastocyst complementation, and analyzed current progress that gives us the possibility to grow human organs in chimeric animals. We also considered the barriers and issues preventing the successful implementation of interspecific blastocyst complementation in practice, and discussed the further development of this method.

Erratum to: "Anxiety and neurometabolite levels in the hippocampus and amygdala after prolonged exposure to predator-scent stress".

Vavilovskii Zhurnal Genetiki i Selektsii = Vavilov Journal of Genetics and Breeding. 2019;23(5):582-587 (in Russian) Page 587, in Acknowledgements instead of The animals and behavioral testing are supported by the budget project (No. 0324-2019-0041). The MRI study is supported by the budget project (No. 0259-2019-0004). All studies are implemented using the equipment of Center for Genetic Resources of Laboratory Animals at ICG SB RAS, supported by the Ministry of Education and Science of Russia (Unique ID# of the project: RFMEFI62117X0015). should read The animals and behavioral testing are supported by the budget project (No. 0324-2019-0041). The MRI study is supported by the budget project (No. 0259-2019-0004). All studies are implemented using the equipment of Center for Genetic Resources of Laboratory Animals at ICG SB RAS, supported by the Ministry of Education and Science of Russia (Unique ID# of the project: RFMEFI62117X0015). The study was conducted within the basic part of the state task of the Ministry of Science and Higher Education of the Russian Federation (No. 17.7255.2017/8.9). The original article can be found under DOI 10.18699/VJ19.528.

TNFα is responsible for the canonical offspring number-size trade-off.

There is a canonical life-history trade-off between quantity and quality of offspring, but molecular determinants for this are unknown. Here, we show that knockout of tumor necrosis factor (TNF-KO) in mice switched a relation between the number and size of developing embryos from expectedly negative to unexpectedly positive. Depletion of TNFα imbalanced humoral and trophic maintenance of embryo growth during gestation with respect to the litter size. The levels of embryotrophic GM-CSF cytokine and placental efficiency attained positive correlations with the number and size of embryos in TNF-KO females. Thus, TNFα oversees mother's resource allocations to balance embryo growth with the number of offspring. Consequently, this suggests an intricate link between the number-size trade-off and immunity given a pivotal role of TNFα in immune homeostasis.

Selective Cytotoxicity of Manganese Nanoparticles against Human Glioblastoma Cells.

Toxicity of different types of manganese nanoparticles against glioblastoma U-87MG and U-251 cells and normal human cells was studied using MTT test. The selectivity of the toxic effect of nanoparticles was evaluated as the ratio of 50% cytotoxic concentration (СС50) for human embryos fibroblasts (FECh-15) to their СС50 for tumor cells. Five of 6 samples of tested nanoparticles demonstrated selective toxic effect in vitro. Manganese oxide nanoparticles were characterized by maximum selectivity (СС50 6.9 nM and 2.1 nM for U-87MG and U-251 cells, respectively): selectivity index for glioblastoma U-87MG and U-251 cells was 29 and 95.2, respectively. Manganese oxide nanoparticles used for MRI detection of gliomas can be used for designing an oncolytic agent for the treatment of glial tumors in humans.

Effects of a compound from the group of substituted thiadiazines with hypothermia inducing properties on brain metabolism in rats, a study in vivo and in vitro.

The aim of the present study was to examine how administration of a compound of 1,3,4- thiadiazine class 2-morpholino-5-phenyl-6H-1,3,4-thiadiazine, hydrobromide (L-17) with hypothermia inducing properties affects the brain metabolism. The mechanism by which L-17 induces hypothermia is unknown; it may involve hypothalamic central thermoregulation as well as act via inhibition of energy metabolism. We tested the hypothesis that L-17 may induce hypothermia by directly inhibiting energy metabolism. The study in vivo was carried out on Sprague-Dawley adult rats. Two doses of L-17 were administered (190 mg/kg and 760 mg/kg). Brain metabolites were analyzed in control and treated groups using magnetic resonance spectroscopy, along with blood flow rate measurements in carotid arteries and body temperature measurements. Further in vitro studies on primary cultures from rat hippocampus were carried out to perform a mitochondria function test of L-17 pre-incubation (100 µM, 30 min). Analysis of brain metabolites showed no significant changes in 190 mg/kg treated group along with a significant reduction in body temperature by 1.5°C. However, administration of L-17 in higher dose 760 mg/kg provoked changes in brain metabolites indicative of neurotoxicity as well as reduction in carotid arteries flow rate. In addition, a balance change of excitatory and inhibitory neurotransmitters was observed. The L-17 pre-incubation with cell primary cultures from rat brain showed no significant changes in mitochondrial function. The results obtained in the study indicate that acute administration of L-17 190 mg/kg in rats induces mild hypothermia with no adverse effects onto brain metabolism.

Stress-sensitive arterial hypertension, haemodynamic changes and brain metabolites in hypertensive ISIAH rats: MRI investigation.

NEW FINDINGS: What is the central question of this study? Stress-sensitive arterial hypertension is considered to be controlled by changes in central and peripheral sympathetic regulating mechanisms, which eventually result in haemodynamic alterations and blood pressure elevation. Therefore, study of the early stages of development of hypertension is of particular interest, because it helps in understanding the aetiology of the disease. What is the main finding and its importance? Non-invasive in vivo investigation in ISIAH rats demonstrated that establishment of sustainable stress-sensitive hypertension is accompanied by a decrease in prefrontal cortex activity and mobilization of hypothalamic processes, with considerable correlations between haemodynamic parameters and individual metabolite ratios. The study of early development of arterial hypertension in association with emotional stress is of great importance for better understanding of the aetiology and pathogenesis of the hypertensive disease. Magnetic resonance imaging (MRI) was applied to evaluate the changes in haemodynamics and brain metabolites in 1- and 3-month-old inherited stress-induced arterial hypertension (ISIAH) rats (10 male rats) with stress-sensitive arterial hypertension and in control normotensive Wistar Albino Glaxo (WAG) rats (eight male rats). In the 3-month-old ISIAH rats, the age-dependent increase in blood pressure was associated with increased blood flow through the renal arteries and decreased blood flow in the lower part of the abdominal aorta. The renal vascular resistance in the ISIAH rats decreased during ageing, although at both ages it remained higher than the renal vascular resistance in WAG rats. An integral metabolome portrait demonstrated that development of hypertension in the ISIAH rats was associated with an attenuation of the excitatory and energetic activity in the prefrontal cortex, whereas in the WAG rats the opposite age-dependent changes were observed. In contrast, in the hypothalamus of 3-month-old ISIAH rats, an increase in energetic activity and prevalence of excitatory over inhibitory neurotransmitters was noticed. The blood flow through the main arteries showed a positive correlation with glutamate and glutamine levels in the hypothalamus and a negative correlation with the hypothalamic GABA level. The blood pressure values were positively correlated with hypothalamic choline levels. Thus, the early development of stress-sensitive hypertension in the ISIAH rats is accompanied by considerable changes both in brain metabolite ratios and in the parameters of blood flow through the main arteries.

Parameters of Blood Flow in Great Arteries in Hypertensive ISIAH Rats with Stress-Dependent Arterial Hypertension.

Magnetic resonance angiography was used to examine blood flow in great arteries of hypertensive ISIAH and normotensive Wistar rats. In hypertensive ISIAH rats, increased vascular resistance in the basin of the abdominal aorta and renal arteries as well as reduced fraction of total renal blood flow were found. In contrast, blood flow through both carotid arteries in ISIAH rats was enhanced, which in suggests more intensive blood supply to brain regulatory centers providing enhanced stress reactivity of these rats characterized by stress-dependent arterial hypertension.

[SPECTRUM OF SPONTANEOUS PATHOLOGICAL CHANGES IN MOLE-VOLES AND THE EFFECT OF MITOCHONDRIA-TARGETED ANTIOXIDANT SkQ1 ON IT].

The mole vole (Ellobius talpinus (Pallas), Rodentia) is the object of interest for cytogenetics, ecology and gerontology research, peculiarly because of partial similarity of this animal to the unique long-living rodent, mole rat. In this work, the mole vole has been found to have very specific spectrum of tumors and non-tumor pathologies which vastly differs from pathological lesions spectrum in mole rat, laboratory mouse, rat and hamster. Mole voles had relatively small tumor incidence (9% totally in the observed population and 16% in animals dead after the achievement of the first tumor development age) and long minimal span of tumor latency (549 days) that is why this species could be categorized as cancer-resistant in compare to laboratory rodents (mice, rats, hamsters). The most common tumors in mole voles were hepatocellular neoplasms. Main non-tumor lesions were pneumonias and other septic and purulent diseases. Non-incapsulated, Gram-positive streptococci have been elucidated to be sole etiological agents in lesioned tissues. It is very important that septic and purulent diseases in mole voles commonly induced the neoplasia-like lesions (leukemoid reaction and "inflammatory pseudotumors"). Sex differences in pathological spectrum and incidences were not found. At last, it has been established that mitochondria-targeted antioxidant SkQ1 (which prolonged mole vole life span) did not significantly influence on spectrum and incidences of pathologies in mole voles.

Nasal aerodynamics protects brain and lung from inhaled dust in subterranean diggers, Ellobius talpinus.

Inhalation of air-dispersed sub-micrometre and nano-sized particles presents a risk factor for animal and human health. Here, we show that nasal aerodynamics plays a pivotal role in the protection of the subterranean mole vole Ellobius talpinus from an increased exposure to nano-aerosols. Quantitative simulation of particle flow has shown that their deposition on the total surface of the nasal cavity is higher in the mole vole than in a terrestrial rodent Mus musculus (mouse), but lower on the olfactory epithelium. In agreement with simulation results, we found a reduced accumulation of manganese in olfactory bulbs of mole voles in comparison with mice after the inhalation of nano-sized MnCl2 aerosols. We ruled out the possibility that this reduction is owing to a lower transportation from epithelium to brain in the mole vole as intranasal instillations of MnCl2 solution and hydrated nanoparticles of manganese oxide MnO · (H2O)x revealed similar uptake rates for both species. Together, we conclude that nasal geometry contributes to the protection of brain and lung from accumulation of air-dispersed particles in mole voles.

[Aerosol deposition in nasal passages of burrowing and ground rodents when breathing dust-laden air].

In subterranean rodents, which dig down the passages with frontal teeth, adaptation to the underground mode of life presumes forming of mechanisms that provide protection against inhaling dust particles of different size when digging. One of such mechanisms can be specific pattern of air flow organization in the nasal cavity. To test this assumption, comparative study of geometry and aerodynamics of nasal passages has been conducted with regard to typical representative of subterranean rodents, the mole vole, and a representative of ground rodents, the house mouse. Numerical modeling of air flows and deposition of micro- and nanoparticle aerosols indicates that sedimentation of model particles over the whole surface of nasal cavity is higher in mole vole than in house mouse. On the contrary, particles deposition on the surface of olfactory epithelium turns out to be substantially less in the burrowing rodent as compared to the ground one. Adaptive significance of the latter observation has been substantiated by experimental study on the uptake ofnanoparticles of hydrated manganese oxide MnO x (H2O)x and Mn ions from nasal cavity into brain. It has been shown with use of magnetic resonance tomography method that there is no difference between studied species with respect to intake of particles or ions by olfactory bulb when they are introduced intranasally. Meanwhile, when inhaling nanoparticle aerosol of MnCl2, deposition of Mn in mouse's olfactory bulbs surpasses markedly that in vole's bulbs. Thereby, the morphology of nasal passages as a factor determining the aerodynamics of upper respiratory tract ensures for burrowing rodents more efficient protection of both lungs and brain against inhaled aerosols than for ground ones.

[Selection for catatonic reaction in rats: a study of interstrain differences by magnetic resonance imaging].

Brain studies by magnetic resonance imaging, angiography, and spectroscopy have been performed with rat strains Wistar, GC (genetic and catatonia), and PM+ (pendulum movements). Both GC and PM+ rats show similar deviations from the ancestral Wistar population in having smaller areas of the right striatum (coronal slice). The anterior horns of lateral ventricles in GC rats are smaller than in the control strain. The maximum blood flow velocity in the common carotid arteries of PM+ rats is greater. The GC and PM+ strains differ in myo-inositol level in the hippocampus. The PM+ strain is characterized by a lower taurine level in the hippocampus, which may be one of the participants regulated the predisposition to audiogenic seizures.

[Conjugated variability of spontaneous activity and behavioral response to olfactory stimuli in the taiga tick (Ixodes persulcatus)].

According to -the automatic tracing of the movement of ticks in a Petri dish, motivational variability of the spontaneous activity and behavioral response of the taiga tick to olfactory stimuli was analyzed. In the studied sample, two groups of ticks that differ in the movement trajectory in the absence of stimulus were isolated, including ticks that mainly moved on the edge of the dish at maximum accessible height (group 1) and ticks that mainly moved at the bottom and wall of the dish (group 2). It was registered that ticks of group 1 (as opposed to ticks of group 2) demonstrated a pronounced behavioral response to olfactory stimuli (human synthetic pheromones and ammonia) and negative geotaxis. It was established that belonging to these groups depended On the time of day when the testing was performed and did not depend on the physiological age and infectious status.

Association of polymorphism harbored by tumor necrosis factor alpha gene and sex of calf with lactation performance in cattle.

In a majority of mammals, male infants have heavier body mass and grow faster than female infants. Accordingly, male offspring nursing requires a much greater maternal energy contribution to lactation. It is possible that the maternal-fetal immunoendocrine dialog plays an important role in female preparation for lactation during pregnancy. Immune system genes are an integral part of gene regulatory networks in lactation and tumor necrosis factor alpha (TNFα) is a proinflammatory cytokine that also plays an important role in normal mammary gland development. The aim of this study was to evaluate the influence of the sex of calf and/or the -824A/G polymorphism in the promoter region of TNFα gene on milk performance traits in Black Pied cattle over the course of lactation. We also studied the allele frequency differences of -824A/G variants across several cattle breeds, which were bred in different climatic conditions. The G allele frequency decreased gradually over the course of lactation events in the Black Pied dairy cattle because of a higher culling rate of cows with the G/G genotype (p<0.001). In contrast to the genotypes A/A and A/G, cows with G/G genotype showed significant variability of milk and milk fat yield subject to sex of delivered calf. Milk yield and milk fat yield were significantly higher in the case of birth of a bull calf than with a heifer calf (p<0.03). The G allele frequency varies from 48% to 58% in Grey Ukrainian and Black Pied cattle to 77% in aboriginal Yakut cattle. Our results suggest that the TNFα -824A/G gene polymorphism may have an influence on the reproductive efforts of cows over the course of lactation events depending on the sex of progeny. Allocation of resources according to sex of the calf allows optimizing the energy cost of lactation. This may be a probable reason for high G allele frequency in Yakut cattle breeding in extreme environmental conditions. Similarly, the dramatic fall in milk production after birth of a heifer calf increases the probability of culling for the cows with the G/G genotype in animal husbandry.

[Reproductive success of males of the ICR outbred line during propagation against the background of antigenic stimulation].

Diversity of viruses, bacteria, microscopic fungi, and endo- and ectoparasites is an inevitable environmental factor that influences the host reproduction and that is determined not only by negative effects of infectious diseases but also by activation of protective mechanisms, which provide a confrontation to the pressure of parasites. In the present work, hemocyanin was injected into males of the ICR outbred line in order to study reproductive consequences of antigenic stimulation of males. Intact females were added to control and antigen-stimulated males at the initial stage of antibody formation. During 6 days of combined keeping, a significantly greater amount of ovulated egg cells and living embryos were registered in the females added to males that were injected with hemocyanin compared with that theoretically expected for equal reproductive yield. Females covered by antigen-stimulated males bred larger embryos compared with those in the control. Indices of female fertility depended on prevalence of cellular (Th1) or humoral (Th2) immune responses in antigen-stimulated males. Shift of Th1/Th2 balance resulted in higher preimplantation embryonic losses in females covered by males with a prevalence of cellular immune response; however, they bred larger embryos. Thus, it was established that activation of the immune system in males does not influence their reproductive abilities. This allows us, on the one hand, to explain the contribution of protective reactions of the organism in the increase in fertility of the mammals that inhabit territories with high specific abundance of parasites; on the other hand, it demonstrates new ways of the management of the reproduction of animals bred under human control.

[Factors of stress in a local population of water vole].

Physiological mechanisms of stress have a multiple influence on the implementation of the adaptive capacity of individuals. From this perspective, analysis of factors determining the stress level of animals in changing environment acquires important ecological and evolutionary significance. In the paper the results are presented of long-term studies carried out at a site of irrigative channel being populated by water voles every year. The results show that high stress level of males is observed in connection with shortages of environmentally significant resources--food and sexual partners. An activation of adrenocortical function due to resources deficit is formed as a result of exacerbation of intraspecific competition that occurs at both low food supply and reducion in proportion of females in the local population. The effects of these factors are mediated through changes in spatio-ethological structure of the studied populations which are manifested in increased overlapping of individual home ranges. Food supply and lack of females have different effects on the level of glucocorticoids in resident and nonresident males. These results indicate that social interactions in water vole is the real stress factor even when total population is significantly depleted, which in North Baraba occurs when territory watering is reduced and suitable summer habitats are not plenty enough.

[Density-dependent regulation in populations of red-backed voles (Myodes rutilus) in optimal and suboptimal habitats of south-west Siberia].

In a population of red-backed voles (Myodes rutilus) that live in optimal habitats (mountain taiga of North-Eastern Altai) in the years of peak density we have observed total suppression of sexual maturation of young animals which is known to be the main mechanism of density regulation. Increase of voles' local density is accompanied by the increase of glucocorticoids in blood of mature and immature individuals of both sexes that argues for the important role of hypothalamic-pituitary-adrenal axis in density dependent regulation. Another population of red-backed voles from south-west Siberia that live in suboptimal habitats (Novosibirsk city vicinity), had significantly lower density. Here, the dynamics of demographic traits and endocrine status of the individuals did not correlate with interannual fluctuations of abundance and density. Even though, the possibility that in suboptimal conditions local density occasionally reaches the values sufficient for the induction of self-regulation cannot be excluded.