This study aimed at investigating whether a porcine follicular fluid (pFF) supplementation positively affects the characteristics of donor cells and the developmental competence of porcine cloned embryos. Ear fibroblast cells (donor cell) from an Massachusetts General Hospital miniature pig were cultured in different culture methods: (1) Dulbecco's modified Eagle's medium (DMEM)+10% FBS (Control); (2) DMEM+0.5% FBS (SS); and (3) DMEM+10% FBS+10% pFF (pFF) for 72 h. In each conditioned medium, the concentrations of 4 amino acids (Thr, Glu, Pro, and Val) in the pFF group were significantly different from those in the control group (p<0.05 or p<0.01). The proliferation of the cells cultured in the SS group was significantly lower than that of the other treatment groups (p<0.01). The population of apoptotic and necrotic cells in the SS group was significantly higher than that of either the control or the pFF group (p<0.01). The number of embryos that cleaved (p<0.05) and developed into blastocysts (p<0.01) in the SS group was significantly lower than that of either the control or the pFF group. Compared to other groups, the blastocysts produced from the donor cells in the pFF group had higher total cells and lower apoptotic cells (p<0.05). It can be concluded that pFF supplementation in the donor cell culture medium positively affects cell death, cell cycle and quality of the cloned blastocyst.
In this study, we analyzed expression patterns of apoptotic and autophagic gene products in culture follicular cells of normal and miniature pigs to assess the effect of hormones on the choice for programmed cell death. Autophagic activity progressively increased from control cultures to luteinizing hormone (LH)-treated cultures of follicular cells of normal pigs, but decreased from the LH to follicle stimulating hormone (FHS) +LH-treated cultures. Expression of Casp-3 protein in follicular cells was highest in LHtreated cultures, but the activity of Casp-3 decreased in the control, FSH-treated, and FSH+LH-treated cultures. The activity of the apoptosis protein was highly expressed in the control, LH-treated, and FSH+LH-treated follicular cells of miniature pigs, but autophagy- associated proteins were expressed at low levels in all treatments groups of the miniature pig. The expression of autophagy and apoptosis proteins appeared similar in control and rapamycin-treated cells. In addition, stimulation with FSH triggered the activation of autophagy in the follicular cells of normal pigs, but induced apoptosis in the follicular cells of miniature pigs. A similar effect was obtained when LH was applied. These results suggest that the autophagy process and FSH stimulation is more effective for stable and innovative follicular cell development.
This study was carried out to determine the effect of cumulus cell attachment and various factors on in vitro maturation of pig foflicular oocytes. Oocytes with various configuration of cumulus cell mass were collected ftom ovaries of mature gilts by asperating with syringe equipped with needles of different gauges, follicle size and with or without cumulus cells. They were cultured in TCM-199 mediun containing FGS(fetal calf serum) for 30~48 hours in incubator with air containing 5% at 38.5. Mter orcein staining at in vitro maturation condition, GV, GVBD, anaphase, telophase and M II were observed. Results are surumarized as follows: 1. Recovery rates were 55.8, 55.5 and 34.4% when the cumulus-compacted oocytes were collected with 18, 21, 26 gauge needles of syringes, respectively. 2. 79% of oocytes with compacted cumulus cells were at GV stage and most of the oocytes with partially denuded and denuded cumulus cells were from GVBD to M- II stages. 3. Percentage of mature oocytes among those which are follicular diameter of 1~2, 3~6 and over 6 mm was 42.6, 53.2 and 60.8%, respectively. 4. Percentage of mature oocytes among those which are compacted, partially denuded and denuded was 60.5, 46.2 and 35.4% respectively. 5. Percentage of mature oocytes in co-cultured with monolayers of cumulus cells was higher (57.1%) than that found with oocytes cultured alone (53.4%).
Fas ligand (FasL) and its receptor Fas have been implicated in granulosa cell apoptosis during follicular atresia. Although interferon-gamma (IFN-γ) is believed to be involved in the regulation Fas expression in differentiated granulosa or granulosa-luteal cells, the expression of this cytokine and its role in the regulation of the granulosa cell Fas/FasL system and apoptosis during follicular maturation have not been thoroughly investigated. In the present study, we have examined the presence of IFN-γ in ovarian follicles at different stage of development by immunohistochemistry and related their relative intensities with follicular expression of Fas and FasL, and with differences in granulosa cell sensitivity to Fas activation by exogenous agonistic Anti-Fas monoclonal antibody (Fas mAb). Although IFN-γ immunostaining was detectable in oocyte and granulosa cells in antral follicles, most intense immunoreactivity for the cytokine was observed in these cells of preantral follicles. Intense immunoreactivity for IFN-γ was most evident in granulosa cells of atretic early antral follicles where increased Fas and FasL expression and apoptosis were also observed. Whereas low concentrations of IFN-γ (10-100 U/mL) significantly increased Fas expression in undifferentiated granulosa cells (from preantral or very early antral follicles) in vitro, very higher concentrations (≥ 1,000 U/mL) were required to up-regulate of Fas in differentiated cells isolated from eCGprimed (antral) follicles. Addition of agonistic Fas mAb to cultures of granulosa cells at the two stages of differentiation and pretreated with IFN-γ (100 U/mL) elicited morphological and biochemical apoptotic features which were more prominent in cells not previously exposed to the gonadotropin in vivo. These findings suggested that IFN-γ is an important physiologic intra-ovarian regulator of follicular atresia and plays a pivotal role in regulation of expression of Fas receptor and subsequent apoptotic response in undifferentiated (or poorly differentiated) granulosa cells at an early (penultimate) stage of follicular development.
포유류 난포의 폐쇄 과정은 매우 정교한 내분비적 조절작용에 의해 일어나며, 이 과정중에 발생하는 난포 내 과립세포의 퇴화는 핵응축 현상을 동반하는 것으로 알려져 있다. 본 연구는 핵응축 현상과 관련하여 돼지 난소 내 폐쇄난포의 과립세포가 퇴화 시 동반되는 세포 사멸이 아포토시스의 과정에 의해서 일어나는지의 여부와 아포토시스 관련 주요 단백질 분해 효소인 캐스파제-3과 연관된 세포 사멸 기전과 관련이 있는지에 대해서 조사하고자 하였다. 돼지 난소로부터 정