TY - JOUR
T1 - Relationship between the number of cells surrounding oocytes and energy states of oocytes
AU - Munakata, Yasuhisa
AU - Ichinose, Tomoya
AU - Ogawa, Kaori
AU - Itami, Nobuhiko
AU - Tasaki, Hidetaka
AU - Shirasuna, Koumei
AU - Kuwayama, Takehito
AU - Iwata, Hisataka
N1 - Funding Information:
This work was supported by a Grant-in-Aid for Scientific Research C (KAKENHI, grant number: 16K07996 and 25450400) from the Japan Society for the Promotion of Science.
Publisher Copyright:
© 2016 Elsevier Inc.
PY - 2016/10/15
Y1 - 2016/10/15
N2 - Lipid content, ATP content, and histone acetylation are thought to reflect the energy state of cells. In addition, the energy state closely associates with growth and developmental ability of oocytes. Oocyte growth is accompanied by active proliferation of the surrounding granulosa cells (GCs), and GCs play a key role in the provision of energy substrates to the oocytes. In the present study, we first examined the relationship among the average number of GCs per follicle, the average number of cumulus cells (CCs) per oocyte, and the average lipid content in oocytes that developed in vivo within individual donor gilts. Second, we validated the relationship between the number of cells surrounding oocytes and the energy states of oocytes by using an IVC system of oocyte granulosa cell complexes (OGCs) derived from early antral follicles. We collected cumulus cells and oocyte complexes (COCs) from antral follicles (3–5 mm in diameter) and found that average lipid content in oocytes significantly correlated with the average number of both GCs/follicle and CCs/oocyte (P < 0.05). In the next series of experiments, we collected OGCs from early antral follicles (0.5–0.7 mm in diameter), and cultured them for 14 days, and then determined the cell number of OGCs, as well as the lipid content, ATP content, and acetylation level of H4K12 in oocytes grown in vitro. In addition, glucose consumption by OGCs was calculated from the sample media collected at Days 13 and 14. The lipid content of oocytes grown in vitro, significantly correlated with the number of cells surrounding the oocytes (P < 0.01) and with the level of glucose consumption by OGCs (P < 0.01). In addition, both ATP content and H4K12 acetylation levels of oocytes grown in vitro significantly correlated with the number of cells surrounding the oocytes (P < 0.05) and glucose consumption by OGCs (P < 0.05). In conclusion, the lipid content of oocytes depends on the number of cells surrounding the oocytes, and glucose uptake by OGCs is crucial for lipid content and ATP content, and H4K12 acetylation in oocytes.
AB - Lipid content, ATP content, and histone acetylation are thought to reflect the energy state of cells. In addition, the energy state closely associates with growth and developmental ability of oocytes. Oocyte growth is accompanied by active proliferation of the surrounding granulosa cells (GCs), and GCs play a key role in the provision of energy substrates to the oocytes. In the present study, we first examined the relationship among the average number of GCs per follicle, the average number of cumulus cells (CCs) per oocyte, and the average lipid content in oocytes that developed in vivo within individual donor gilts. Second, we validated the relationship between the number of cells surrounding oocytes and the energy states of oocytes by using an IVC system of oocyte granulosa cell complexes (OGCs) derived from early antral follicles. We collected cumulus cells and oocyte complexes (COCs) from antral follicles (3–5 mm in diameter) and found that average lipid content in oocytes significantly correlated with the average number of both GCs/follicle and CCs/oocyte (P < 0.05). In the next series of experiments, we collected OGCs from early antral follicles (0.5–0.7 mm in diameter), and cultured them for 14 days, and then determined the cell number of OGCs, as well as the lipid content, ATP content, and acetylation level of H4K12 in oocytes grown in vitro. In addition, glucose consumption by OGCs was calculated from the sample media collected at Days 13 and 14. The lipid content of oocytes grown in vitro, significantly correlated with the number of cells surrounding the oocytes (P < 0.01) and with the level of glucose consumption by OGCs (P < 0.01). In addition, both ATP content and H4K12 acetylation levels of oocytes grown in vitro significantly correlated with the number of cells surrounding the oocytes (P < 0.05) and glucose consumption by OGCs (P < 0.05). In conclusion, the lipid content of oocytes depends on the number of cells surrounding the oocytes, and glucose uptake by OGCs is crucial for lipid content and ATP content, and H4K12 acetylation in oocytes.
KW - ATP
KW - Acetylation
KW - Glucose
KW - Lipid
KW - Oocyte
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U2 - 10.1016/j.theriogenology.2016.05.036
DO - 10.1016/j.theriogenology.2016.05.036
M3 - Article
C2 - 27402087
AN - SCOPUS:84989921284
SN - 0093-691X
VL - 86
SP - 1789-1798.e1
JO - Theriogenology
JF - Theriogenology
IS - 7
ER -