• Clinical and Experimental Reproductive Medicine
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• v.24 no.1
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• pp.1-11
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• 1997

It is well known that the zona pellucidae of mouse oocytes become "hardened" when they are allowed to mature in vitro in the absence of serum components. To see if oocytes already undergone meiotic resumption in vivo exhibit similar zona hardening, hardening of ZP of cumulus-enclosed oocytes(CEOs) was examined after culture in vitro since their release from follicles various hours after hCG injection. When CEOs matured in vivo for 3h or longer were subjected to culture in vitro for 14h with BSA alone, zona hardening was significantly reduced compared to those cultured in vitro from the begining of maturation. However, when CEOs matured in vivo for 5h were freed from cumulus cells and then cultured in vitro with BSA alone, little reduction of zona hardening was observed. Preincubation of CEOs for 5h with fetuin, one of the well known inhibitor of in vitro zone hardening, did not prevent zona hardening during its subsequent culture of CEOs for 14h without fetuin. However, when CEOs precultured with both fetuin and PMSG for 5h and then further cultured with BSA alone for 14h, zona hardening was dramatically reduced. Under these conditions, the expansion of cumulus cell was observed. In addition, CEOs cultured with both BSA and dbcAMP to prevent their meiotic resumption showed a significant increase of zona hardening. Whether the observed zona hardening was correlated with the conversion of ZP2 to $ZP2_{f}$ was examined. Zona pellucida, isolated from CEOs matured for 5h in vivo and then further cultured with BSA alone was subjected to SDS-PAGE. Most of ZP2 molecules from these CEOs did not undergo conversion from ZP2 to $ZP2_{f}$. From these results, it is concluded that CEOs undergone meiotic resumption in vivo do not exhibit zona hardening when they were subsequently cultured in vitro without serum components. It appears that cumulus cells play an important role in this phenomenon.

• Anatomy and Cell Biology
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• v.57 no.2
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• pp.163-171
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• 2024

In the last decade, melatonin has gained recognition as a potent scavenger and an effective antioxidant capable of neutralizing free radicals, including reactive oxygen species. Additionally, it exhibits anti-apoptotic properties. In this review, we will examine a compilation of articles that explore the cellular signaling function of melatonin on spermatogonial stem cells (SSCs) and adjacent cells such as Sertoli and Leydig cells. These cells play a crucial role in the proliferation of SSCs both in vitro and in vivo. In this review, we analyze the function of melatonin in the proliferation of SSCs from other aspects. For this purpose, we examine the articles based on the presence of melatonin on SSCs in four groups: As a supplement in SSCs medium culture, SSCs three-dimensional culture system, SSCs freezing medium, and as a therapeutic factor in vivo. Mechanisms of growth and proliferation of SSCs were considered. The purpose of this study is to investigate the potential effects of melatonin as a powerful antioxidant or growth stimulant for SSCs, both in vivo and in vitro.

• Journal of Embryo Transfer
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• v.5 no.2
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• pp.45-55
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• 1990

The in-vitro fertilization in human clinic and animal reproduction is a very important technique but the rate of success is still low. When the in-vitro fertilization and culture of gametes or embryos were done under the condition which Hema hydrogel chamber were implanted into the peritoneal cavity of mouse, the in-vitro fertilization and development of embryos could be significantly improved and the cell-block under in-vitro culture could be overcome. Also, the Rema hydrogel chamber was very useful for the protection of isolated blastomeres. It is concluded that the polymerized Hema (pHema) hydrogel chamber may be effectively used in the fields of embryo transfer and in vitro fertilization.

• Journal of Animal Reproduction and Biotechnology
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• v.36 no.4
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• pp.183-188
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• 2021

In vitro maturation (IVM) of oocytes is the procedure where the immature oocytes are cultivated in a laboratory until they are mature. Since IVM oocytes generally have low developmental competence as compared to those matured in vivo, development of an optimal IVM culture system by fine-tuning culture conditions is crucial to maintain high quality. In-depth knowledge and a deep understanding of the in vivo physiology of oocyte maturation are pre-requisites to accomplish this. Within ovarian follicles, various signaling pathways that drive oocyte development and maturation regulate interaction between oocytes and surrounding somatic cells. This review discusses the sonic hedgehog (SHH) signaling pathway, which has been demonstrated to be intimately involved in folliculogenesis and oocyte maturation. Advances in elucidating the role of the SHH signaling pathway in oocyte maturation will aid attempts to improve the current inferior in vitro oocyte maturation system.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.118.2-119
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• 2003

This study was undertaken to assess overall effects of bisphenol A, a monomer widely used in manufacturing polycarbonate plastics or epoxy resin, exposure on immune system of mice. For in vitro evaluation, serial concentration of SPA was added into culture of various immune cells from normal female ICR mice, and for in vivo or ex vivo assessment, mice were orally exposed to BPA dissolved in olive oil as doses of 500, 1000, 2000 mg/g b.w. for acute expose or 100, 500, 1000 mg/kg/day b.w. 5days a week for subacute exposure. (omitted)

• Journal of Applied Biological Chemistry
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• v.48 no.4
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• pp.170-177
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• 2005

Oriental medicinal herb extracts (OHE) showing anticancer activities were investigated for effectiveness as antiviral drugs. Infection of MuLV to cell line resulted in formation of giant syncytia. Number of giant syncytia in culture treated with OHE decreased by 40% compared to that of non-OHE-treated cell culture. To determine OHE effects on progeny release, RT-PCR was performed. In vivo animal studies demonstrated effectiveness of OHE as antiviral drug when administered orally. After OHE administration, viral cytopathic effects decreased. Infected mice showed splenomegaly and over-proliferation of lymphocytes with decreased CD4+ cell counts. These symptoms decreased in OHE-treated mice, indicating OHE maybe useful therapeutics against MuLV/MAIDS as Human Immunodeficiency Virus (HIV)/AIDS animal model. Results show XC plaque assay and in vivo MAIDS model using MuLV are suitable tools for screening anti-retroviral drug candidates.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.1
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• pp.1-8
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• 1999

In order to study the implantation mechanism various methods for culture of endometrial cells in vitro have been attempted. However, a disadvantage is that primary cultures of stromal and epithelial cells do not have the ability to differentiate, and therefore cannot be reproduced in the same manner as in vivo endometrium. The object of this study is to establish a three dimensional culture of endometrial cells which are both morphologically and functionally identical to in vivo endometrium. Endometrial tissues obtained after hysterectomies were cut into thin slices and treated with collagenase and trypsin-EDTA. The stromal cells and the epithelial cells were separated by centrifugation and cultured for 24 hours in DMEM media containing 10% FCS, 100 nM progesterone, and 1 nM estradiol. The cultured stromal cells were mixed with collagen gel and solidified, after which it was covered with matrigel. Epithelial cells were inoculated on the top and then cultured for 3 days. The three dimensionally cultured endometrial cells were stained for integrin ${\alpha}1,\;{\alpha}4,\;{\beta}3$, and cyclooxygenase-l, -2 by immunohistochemistry, which all showed strong expression. The cultured epithelial cells showed the formation of microvilli, tight junctions and pinopodes by electron microscopy. Studies are currently under way utilizing this three dimensional culture model to ascertain the interaction between the embryo and human endometrial cells at the time of implantation, and it is thought that further studies into a new culture environment which would allow longer periods of culture will be necessary.

• Biomolecules & Therapeutics
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• v.10 no.4
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• pp.281-286
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• 2002

In this study, we intended to get a preliminary data for establishing rat tracheal surface epithelial(RTSE) cell culture system as an experimental model for physiology and pharmacology of tracheal epithelial cells. Primary culture on the membrane support and application of the air-liquid interface system at the level of cell layer were performed. The cell growth rate and mucin production rate were measured according to the days in culture. The results were as follows: this culture system was found to manifest mucocilliary differentiation of rat tracheal epithelial cells, the cells were confluent and the quantity of produced and released mucin was highest on culture day 9, the mucin was mainly released to the apical side and tbe free $^3{H}$-glucosamine which was not incorporated to process of synthesis of mucin was left on the basolateral side. Taken together, we suggest that air-liquid interface culture system can be used as a substitute for immersion culture system and as an experimental model for in vivo mucus-hypersecretory diseases.

• Biomaterials and Biomechanics in Bioengineering
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• v.3 no.3
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• pp.141-155
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• 2016

Two-dimensional (2D) cell culture and in vivo cancer model systems have been used to understand cancer biology and develop drug delivery systems for cancer therapy. Although cell culture and in vivo model studies have provided critical contribution about disease mechanism, these models present important problems. 2D tissue culture models lack of three dimensional (3D) structure, while animal models are expensive, time consuming, and inadequate to reflect human tumor biology. Up to the present, scaffolds and 3D matrices have been used for many different clinical applications in regenerative medicine such as heart valves, corneal implants and artificial cartilage. While tissue engineering has focused on clinical applications in regenerative medicine, scaffolds can be used in in vitro tumor models to better understand tumor relapse and metastasis. Because 3D in vitro models can partially mimic the tumor microenvironment as follows. This review focuses on different scaffold production techniques and polymer types for tumor model applications in cancer tissue engineering and reports recent studies about in vitro 3D polymeric tumor models including breast, ewing sarcoma, pancreas, oral, prostate and brain cancers.

• Proceedings of the PSK Conference
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• 2002.04a
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• pp.142.1-142.1
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• 2002