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Dive into the research topics where I. N. Rozhkova is active.

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Featured researches published by I. N. Rozhkova.


Russian Journal of Genetics: Applied Research | 2013

Rederivation by embryo transfer in strains of laboratory mice and rats

S. Ya. Amstislavsky; T. N. Igonina; I. N. Rozhkova; E. Yu. Brusentsev; A. A. Rogovaya; D. S. Ragaeva; V. A. Naprimerov; E. A. Litvinova; I. F. Plyusnina; A. L. Markel

Rederivation enables one to decontaminate colonies of laboratory mice and rats from specific pathogens and to convert them to the SPF (specified pathogen free) state. In this study the results of the rederivation of two unique rat strains that were selected at the Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, viz., tame Norway rats, rats with inherited stress-induced arterial hypertension (ISIAH), and the ICR mouse strain, are presented. The SPF state of the rederivated rats was confirmed by indicator animals, which are also called sentinel animals. An optimized rederivation model of laboratory animals is suggested in the article, which includes a series of embryotechnological methods, viz., freezing and cryopreservation of embryos, their decontamination by washing in sterile media, cultivation for 48 h, and, finally, transfer to recipients (with the SPF state). As a result of the application of this model to the ICR strain mice, it was possible to obtain 39 offspring that were born in the conditions of an SPF animal facility. It is worth mentioning that the efficacy of the procedure is in agreement with international standards, with all three lines representing a specific phenotype after undergoing all the procedures of rederivation.


Russian Journal of Developmental Biology | 2012

Coats of preimplantation mammalian embryos as a target of reproductive technologies

I. N. Rozhkova; E. Yu. Brusentsev; S. Ya. Amstislavsky

The structure and function of the mammalian oocyte and preimplantation embryo coverings are described in this review. The integrity of embryonic coverings is the main prerequisite for the success of such technology as preimplantation embryo freezing and, especially, for successful rederivation. On the other hand, results of in vitro fertilization and, sometimes, the results of embryo freezing are improved after perforation of the oocyte/embryonic coverings. Modern reproductive technologies focusing on oocyte/embryonic coverings, such as preimplantation embryo freezing/cryopreservation, in vitro fertilization, intracytoplasmic sperm injection, assisted hatching, immunocontraception, and rederivation, are reviewed. Application of these technologies to different mammalian species is discussed with a special emphasis on the oocytes/preimplantation embryos coverings.


Russian Journal of Developmental Biology | 2015

Embryo and gamete cryopreservation for genetic resources conservation of laboratory animals

S. Ya. Amstislavsky; E. Yu. Brusentsev; K. A. Okotrub; I. N. Rozhkova

The article reviews the use of embryo and gamete cryopreservation for cryobanking the laboratory animal species. Special emphasis is given to the mechanisms of cryoinjury and cryoprotection during program freezing and vitrification. The species specific cryobanking problems are discussed and the prospects to overcome these problems are outlined.


Russian Journal of Developmental Biology | 2017

Developmental aspects of senescence

E. Yu. Brusentsev; M. A. Tikhonova; Yu. E. Herbeck; D. S. Ragaeva; I. N. Rozhkova; S. Ya. Amstislavsky

Different types of senescence and major theories of aging are reviewed, and mechanisms of this complex biological phenomenon are discussed. Emphasis is placed on changes in the nervous systems of mammals and humans with age. Experimental animal models for studying aging and modern approaches to the correction of age-related deterioration are considered. Chemicals and other factors that may alleviate agerelated disorders and slow down senescence are critically reviewed.


Russian Journal of Genetics: Applied Research | 2016

A comparison of different cryoprotectant solutions and thawing methods for the cryopreservation of embryos of mice and rats

T. N. Igonina; E. Yu. Brusentsev; I. N. Rozhkova; V. A. Naprimerov; S. Ya. Amstislavsky

The proper choice of the cryoprotectant and thawing method affects the efficiency of cryopreservation. A freezing-thawing method aimed at the preservation of blastomere cells was evaluated in experiments with ICR mice. The cleavage-stage embryos of ICR mice, GC rats, and OXYS rats were collected on Day 3 of pregnancy and frozen in plastic straws according to the standard procedure. We compared the effect of permeating (ethylene glycol and glycerol) and nonpermeating (sucrose) cryoprotectants and their combinations on the survival rate of embryos after thawing. We also compared the effect of rapid (water bath, 10 s, 37°С) and slow (40 s, room temperature; then 40 s, 30°С) thawing methods. The viability of the embryos of mice and rats after cryopreservation was evaluated by their in vitro culturing after thawing. Our data prove that slow thawing is more suitable for mice embryos and provides a higher survival rate; the addition of sucrose to the basic cryoprotectant (ethylene glycol or glycerol) improves the parameters of the in vitro cultures of embryos after thawing, especially if glycerol is used as the basic cryoprotectant. This freezing-thawing method (glycerole and sucrose as the cryoprotectant solution and slow thawing) was used for cryopreservation of GC and OXYS rats. As a result, the survival rate of embryos after freezing was 68–83.3% and the rate of in vitro development after thawing was 64.7–66.6%.


Russian Journal of Genetics: Applied Research | 2016

Applying reproductive technologies and genome resource banking to laboratory animals

S. Ya. Amstislavsky; E. Yu. Brusentsev; T. O. Abramova; D. S. Ragaeva; I. N. Rozhkova; T. N. Igonina; Elena Kizilova; V. A. Naprimerov; N. Yu. Feoktistova

The Genome Resource Bank (GRB) is a repository of frozen biological material, including semen and embryos. Cryobanking is often used in combination with modern reproductive technologies, such as rederivation, in vitro culture, and embryo transfer. Thirteen mouse and rat strains have been rederived, and 32 are kept in cryostorage at the Institute of Cytology and Genetics, Novosibirsk. Other laboratory animal species have been cryopreserved as well. Embryos of two hamster species (Djungarian and Campbell’s) of the Phodopus genus were cryopreserved, and the viability of thawed embryos was confirmed by their successful development in vitro and in vivo (by transfer to a recipient). The positive effect of the Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) was demonstrated for both of these Phodopus species. Furthermore, the sperm of Djungarian (Phodopus sungorus) and Campbell’s (Phodopus campbelli) hamsters, domestic cat (Felis catusf),leopard cat (Prionailurus bengalensis euptilurus), and bobcat (Lynx rufus) was frozen and cryopreserved. Double staining by SYBR Green/PI, followed by confocal microscopy, demonstrated that more than 40% of amur cat semen retained their viability after cryopreservation. This is the world’s first reported successful freezing of semen of these wild feline species (Prionailurus bengalensis euptilurus). The article reviews the results and discusses the prospects of using reproductive technologies for the conservation of laboratory animal species.


Russian Journal of Genetics: Applied Research | 2016

Effects of reproductive technologies and SPF status on some physiological and behavioral characteristics in rats with arterial hypertension (ISIAH Strain)

D. S. Ragaeva; T. O. Abramova; I. N. Rozhkova; E. Yu. Brusentsev; E. V. Kalinichenko; T. N. Igonina; S. Ya. Amstislavsky

Modern standards of Laboratory Animal Science include working with laboratory animals of a high quality, in particular, with specific pathogen-free (SPF) mice and rats. On the other hand, assisted reproductive technologies (ART) are widely used in modern medicine for human infertility treatment and genome resource banking. In the present study, a comparison of body weight, blood pressure (BP), and behavior in the elevated plus maze (EPM) test was made between three groups of ISIAH (inherited stress induced arterial hypertension) rats: a group of animals that were born and raised in a conventional animal facility and two groups from an SPF animal facility (animals born naturally and animals resulting from ART). There were no changes in BP between the groups, but the behavior of ISIAH rats differed depending on rearing conditions. In particular, the grooming time, as well as the number of defecations and the number of urinations during the test decreased in both groups of ISIAH rats born in the SPF animal facility as compared to ISIAH rats born in the conventional animal facility. The behavior of the ISIAH rat offspring resulting from ART was different from that of the naturally born group: the EPM test revealed reduced anxiety in the former. The results of the present study indicate that the rearing conditions and the reproductive technologies affect some behavioral characteristics in adult ISIAH rats, although they posessed arterial hypertension in all the conditions used in this study.


Brain Research | 2018

Neurodevelopment and behavior in neonatal OXYS rats with genetically determined accelerated senescence

T. N. Igonina; D. S. Ragaeva; Maria A. Tikhonova; Olga M. Petrova; Yuri E. Herbeck; I. N. Rozhkova; Tamara G. Amstislavskaya; Sergey Ya. Amstislavsky

Study of the developmental characteristics and mechanisms of senescence is an important field in brain aging research. The OXYS strain was selected from Wistar rats in Novosibirsk, and it serves as a rat model of accelerated aging. Previously, neurodegenerative processes and aberrant behavior were reported in experiments with adult OXYS rats. In our study, neurodevelopmental reflexes, neuronal density in the prefrontal cortex and hippocampus, and global DNA methylation in the hippocampus are compared between OXYS and WAG (Wistar Albino Glaxo) neonatal pups. The development of the righting, forelimb grasp, and cliff avoidance reflexes is delayed, and body weight gain was deferred in neonatal OXYS pups. Neuronal density in the hippocampus does not differ between one-day-old OXYS and WAG pups. On the sixth day, the neuronal density in OXYS pups is reduced in the CA2 hippocampal zone, augmented in CA3 and DG, and unchanged in CA1. Six-day-old OXYS pups have fewer and smaller pyramidal neurons in the prefrontal cortex as compared to WAG controls. Global DNA methylation levels in the hippocampus of OXYS newborns are significantly lower than in the WAG newborn pups. At the age of six days, the global DNA methylation level decreases in WAG pups, but does not change in OXYS pups. Thus, neonatal OXYS rats show delayed neurodevelopment accompanied by changes in the global DNA methylation pattern in the hippocampus and in neuronal density in the hippocampus and the prefrontal cortex. These changes may be related to accelerated senescence in adult OXYS rats.


Journal of Genetics and Breeding | 2017

Сравнение преимплантационного развития эмбрионов крыс линий OXYS и WAG в условиях in vivo и in vitro

V. V. Kozhevnikova; T. N. Igonina; E. Yu. Brusentsev; Valentina Mokrousova; Elena Kizilova; I. N. Rozhkova; V. A. Naprimerov; S. Ya. Amstislavsky

OXYS rats are the model of precocious senescence. Numerous studies addressed physiology and behavior in rats of this strain during a postnatal period of their life, however, preimplantation development in OXYS rats has not yet been investigated. This study is addressing preimplantation embryonic development in OXYS rats both in vivo and in vitro. Rats of the WAG strain were used as controls. For studying the in vivo development, the embryos were collected from OXYS and WAG rats on day 5 post coitum, the stages of embryo development were estimated, the percentage of embryos at blastocyst stage and the cell numbers in these blastocysts were counted. In a special experiment, for studying in vitro development, the embryos were collected from both rat strains on day 4 post coitum and were cultured in vitro in P1 medium for 48 hours with or without supplementation with IGF-1 (200 ng/mL). Thereafter the percentage of embryos at blastocyst stage and the cell numbers in these blastocysts were counted in the same manner as for the in vivo experiment. This study reports that in vivo derived blastocysts of OXYS rats contain fewer cells on day 5 of their development than in vivo derived blastocysts of WAG rats. In vitro culture of the early preimplantation embryos in P1 medium mitigated the difference in the rate of embryo development between these two strains, the addition of IGF-1 into culture medium exerts neither negative nor positive effect on the rate of in vitro embryo development in rats of both strains.


Russian Journal of Genetics: Applied Research | 2016

Effects of growth factors during in vitro culture of mouse and rat embryos

E. Yu. Brusentsev; T. N. Igonina; I. N. Rozhkova; D. S. Ragaeva; S. Ya. Amstislavsky

The development of embryos of the ICR, HT1AN/lcgn, HT1AC/lcgn, and C57BL/6J-Ay mouse strains, as well as the OXYS/lcgn rat strains, in the culture in vitro was studied under the influence of the granulocyte- macrophage colony stimulating factor (GM-CSF) and epidermal growth factor (EGF). Both mice and rats embryos were initially frozen according to the standard protocol of the freezing program using glycerol and sucrose as cryoprotectant and culture in the rat 1-cell embryo culture medium (R1ECM) for either 24 h (mice) or 72 h (rats) after thawing. The effects of the growth factors were studied on 8-cell embryos in mice and 2–4-cell embryos in rats. The GM-CSF effect resulted in an increase in the percentage of developing embryos in the mice of both strains (HT1AC/lcgn and C57BL/6J-Ay); at the same time, no EGF effect on the mice embryos was found. The situation was the opposite for rats. The EGF effect resulted in the acceleration of the development until the stage of blastocyst in the OXYS/lcgn strain rats, but no GM-CSF effect on the rat embryos was found. The acceleration of the development is observed during the joint culture of 4-cell embryos of the HT1AN/lcgn mice strain with later stages of development (embryos at the morula stage) of the ICR strain. The results of the presented experiments indicate a species specificity of the effect of the growth factors on the mice and rats embryos, as well as demonstrating that joint culture of embryos of the later stages (morula) of mice with earlier stages (4-cell embryos) has a stimulating effect on the latter.

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E. Yu. Brusentsev

Russian Academy of Sciences

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T. N. Igonina

Russian Academy of Sciences

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D. S. Ragaeva

Russian Academy of Sciences

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V. A. Naprimerov

Russian Academy of Sciences

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Elena Kizilova

Russian Academy of Sciences

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Eugeny Brusentsev

Russian Academy of Sciences

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T. O. Abramova

Russian Academy of Sciences

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V. V. Kozhevnikova

Russian Academy of Sciences

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