Isocupressic acid blocks progesterone production from bovine luteal cells.
Journal
American Journal of Chinese Medicine
Journal Volume
30
Journal Issue
4
Pages
533-541
Date Issued
2002
Author(s)
Chen, J.C.
Sheu, S.Y.
Huang, C.C.
Kuo, Y.H.
Chiu, C.H.
Lian, W.X.
Yang, C.J.
Lin, J.H.
Abstract
The needles of ponderosa pine (Pinus ponderosa Laws.) were reported to induce abortions when fed to late-term pregnant beef cows in North America. An in vivo study of pregnant cows suggested that isocupressic acid (IA) was the main abortifacient isolated from needles and bark of the pine. However, the mechanism of abortifacient activity of IA is not clear yet. In a pregnant cow, the corpus luteum of the ovary helps the maintenance of pregnancy by its progesterone production. This study involved the IA extracted from the root of the Taiwan cypress (Juniperus formosana) and used a frozen-thawed bovine luteal cell culture system to investigate the action of IA on progesterone production. Thawed bovine luteal cells (1 × 105 cells/ml/well) in M199 medium were cultured in 24-well culture plates at 37°C in a 5% CO 2 incubator. Ten ml of tested drugs, IA at 1 to 1000 ng/ ml and/or ovine luteinizing hormone (oLH) at 1 to 100 ng/μ1 or 8-bromo-cyclic adenosine monophosphate (8-Br-cAMP) with 0.1-10 mM, were added into each well. After 4 hours of incubation, the media were harvested and assayed for progesterone by an enzyme immunoassay. Progesterone production from cells was the indicator used to evaluate the action of IA. All tested doses of IA significantly inhibited progesterone production in both basal and oLH stimulating conditions. Also those dosages inhibited cyclic adenosine-3',5'- monophosphate (cAMP) stimulation, suggesting a post-cAMP mechanism is involved in the IA action. We concluded that IA can induce pregnant cows to abort partly through blocking luteal function and may be identified as a new abortifacient chemical. © 2002 World Scientific Publishing Company & Institute for Advanced Research in Asian Science and Medicine.
SDGs
Type
journal article