Possible Modulators of IL-8 and GRO-α Production by Granulosa Cells


Address reprint requests to Dr Kosay Zeineh, Department of Obstetrics and Gynecology, Oita Medical University, Hasama-machi, Oita 879-5593, Japan.
E-mail: kosayz@yahoo.ie


Problem:  Interleukin-8 (IL-8) and growth-regulated oncogene-α (GRO-α) have been proved to be important modulators of leukocyte chemotaxis in the mechanism of human ovulation. This study investigated the possible effects of IL-1α, tumor necrosis factor-α (TNF-α), protein kinase C (PKC) activators (TPA), and db-cyclic adenosine monophosphate (cAMP) on IL-8 and GRO-α production by immortalized GC1a and granulosa-lutein cells.

Method of Study:  Confluent granulosa-lutein cells were placed in serum-free medium before incubated for 8 hr with the above-mentioned test agents. Finally, we measured IL-8 and GRO-α levels in the culture media using an enzyme-linked immunosorbent assay (ELISA).

Results:  Treatment of granulosa-lutein cells with of IL-1α (1 nM), TNF-α (1 nM), TPA (1 nM) and db-cAMP (100 μM) produced higher levels of IL-8 than untreated cells by 8 hr (2274.7 ± 146.3, 1489.8 ± 190.1, 1452.9 ± 152.7, 1313.6.6 ± 48.4 pg/mL, respectively; control = 457.7 ± 38.2 pg/mL; P < 0.001). Treatment of granulosa-lutein cells with 1 nM of IL-1α, TNFα, TPA, and db-cAMP (100 μM) resulted in higher levels of GRO-α than untreated cells by 8 hr (993.7 ± 9.5, 171.4 ± 6.5, 147.5 ± 6.7, 472.4 ± 16.2 pg/mL respectively; control = 73.8 ± 8.2 pg/mL; P < 0.001).

Conclusions:  Our data strongly suggests roles for IL-1α, TNFα, and PKC activators in the inflammation–like mechanism of human ovulation. Furthermore, our study suggests a positive, but still debatable, role for cAMP in the same mechanism.