Ts. Nandhra et Rj. Carson, beta-endorphin inhibits the production of interleukin-8 by human chorio-decidual cells in culture, MOL HUM REP, 6(6), 2000, pp. 555-560
Interleukin-8 (IL-8) is produced by human decidual cells in culture, and ma
y play a role in the initiation of parturition. beta-endorphin is released
in significant amounts into the maternal and fetal circulation during labou
r. The effect of beta-endorphin on IL-8 production by human chorio-decidual
cells in culture was investigated. Mixed cells were obtained from the deci
dual surfaces of 35 term placentas. The cells were plated out at 10x10(6) c
ells per well in Roswell Park Memorial Institute 1640 culture medium. After
48 h the cells were washed and incubated with either plain culture medium
(control), 1 mu mol/l progesterone, 1-100 nmol/l beta-endorphin or 1 nmol/l
N-acetyl beta-endorphin. After 48 h, IL-8 concentrations were measured in
the supernatants by enzyme-linked immunosorbent assay (ELISA). Experiments
were repeated in the presence of naloxone (1 mu mol/l) and using calcium-de
ficient culture medium. Progesterone (P < 0.0002) and beta-endorphin (P < 0
.0005) significantly inhibited the production of IL-8. The inhibitory effec
t of beta-endorphin was blocked by naloxone and by using calcium-deficient
medium. N-acetyl beta-endorphin had no significant effect on IL-8 productio
n. These findings suggest that beta-endorphin has an inhibitory effect on I
L-8 production by decidual cells, and that the effect is mediated via opioi
d receptors and is calcium-dependent.