title: Effects of interleukin-8 on estradiol and progesterone production by bovine granulosa cells from large follicles and progesterone production by luteinizing granulosa cells in culture.
abstract: Interleukin 8 (IL-8) is a chemoattractant involved in the recruitment and activation of neutrophils and is associated with the ovulate process. We examined the possible role of IL-8 in steroid production by bovine granulosa cells before and after ovulation. The concentration of IL-8 in the follicular fluid of estrogen-active dominant (EAD) and pre-ovulatory follicles (POF) was higher than that of small follicles (SF). CXCR1 mRNA expression was higher in the granulosa cells of EAD and POF than that of SF. In contrast, CXCR2 mRNA expression was lower in granulosa cells of EAD and POF than in SF. IL-8 inhibited estradiol (E2) production in follicle-stimulating hormone (FSH)-treated granulosa cells at 48 h of culture. IL-8 also suppressed CYP19A1 mRNA expression in FSH-treated granulosa cells. IL-8 stimulated progesterone (P4) production in luteinizing hormone (LH)-treated granulosa cells at 48 h of culture. Although IL-8 did not alter the expression of genes associated with P4 production, it induced StAR protein expression in LH-treated granulosa cells. The expression of CXCR1 mRNA in corpus luteum (CL) did not change during the luteal phase. In contrast, the expression of CXCR2 mRNA in middle CL was significantly higher than in early and regression CL during the luteal phase. In luteinizing granulosa cells, an in vitro model of granulosa cell luteinization, CXCR2 mRNA expression was downregulated, whereas CXCR1 mRNA expression was unchanged. IL-8 also stimulated P4 production in luteinizing granulosa cells. These data provide evidence that IL-8 functions not only as a chemokine, but also act as a regulator of steroid synthesis in granulosa cells to promote luteinization after ovulation.
authors: Graduate School of Animal and Food Hygiene, Obihiro University of Agriculture and Veterinary Medicine, Inada-machi, Obihiro, Hokkaido 080-8555, Japan. shimizut@obihiro.ac.jp
authors: Takashi
authors: T
authors: Shimizu
authors: Ayami
authors: A
authors: Kaji
authors: Chiaki
authors: C
authors: Murayama
authors: Fumie
authors: F
authors: Magata
authors: Koumei
authors: K
authors: Shirasuna
authors: Kaori
authors: K
authors: Wakamiya
authors: Kiyoshi
authors: K
authors: Okuda
authors: Akio
authors: A
authors: Miyamoto
mesh_terms: D000818:Animals; D001141:Aromatase / Q000235:genetics / Q000378:metabolism; D002417:Cattle; D002478:Cells, Cultured; D003338:Corpus Luteum / Q000187:drug effects / Q000378:metabolism; D004958:Estradiol / Q000096:biosynthesis*; D030762:Estrous Cycle / Q000187:drug effects; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D015571:Follicular Fluid / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006107:Granulosa Cells / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D016209:Interleukin-8 / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000494:pharmacology*; D010750:Phosphoproteins / Q000378:metabolism; D011374:Progesterone / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D023062:Receptors, Interleukin-8A / Q000235:genetics / Q000378:metabolism; D023063:Receptors, Interleukin-8B / Q000235:genetics / Q000378:metabolism; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D016209:Interleukin-8; D010750:Phosphoproteins; D012333:RNA, Messenger; D023062:Receptors, Interleukin-8A; D023063:Receptors, Interleukin-8B; D000098682:Steroidogenic Acute Regulatory Protein; D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D001141:Aromatase