| dc.description.abstract | Embelin is a plant extract widely used as a herbal medicine against a wide range of ailments
in humans. Its use has been associated with sexual debility in male subjects. Studies have
shown that it actually posses anti-fertility properties in male laboratory animals. In female
rats, it has been shown to cause fetal resorption and to reduce ovarian weights. However,
studies in the female have not explicitly elucidated the changes that take place at
endocrinological level; neither have they described ovarian morphological changes nor the
evolution of estrous cycles associated with embelin exposure. This study aimed to
accomplish the above.
The effects of embelin on the evolution of estrous cycles, progesterone and
estradiol profiles and ovarian histopathology were examined. Thirty adult (4
months old) regularly cycling female Sprague-Dawley rats were used. They
were given I mllkg bwt. Corn oil (groupI-control, n=10); or embelin
dissolved in corn oil at 10 mg/kg bwt. (groupll-experimental, n=10) and 20
mg/kg bwt. (groupl lI-experimental, n=10). The treatments were given
subcuteneously on alternate days for 20 days. Thus, each animal received a
total of 10 injections by the end of the experiment. Oestrous cycles were
monitored daily by vaginal cytology. Ovarian histopathology and
progesterone and estradiol levels were assessed by standard procedures.
Subcutaneous injections of embelin in this animal model resulted in the
disruption of the regular oestrous cycle patterns. Specifically, 3 animals out
of lOin group II (10 mg/kg bwt. ) and 4 animals out of lOin group III (20
mg/kg bwt. ) essentially remained in dioestrus by the fifth injection. There
was a significant depression of plasma estradiol (P<0.05) and progesterone
(P<0.02) at both dose levels. Histopathological evaluation of the ovaries
from the embelin treated rats revealed the presence of abnormal follicles. In
most follicles, the oocytes showed distortions in their symmetries. There
were no significant changes in the liver and pituitary glands.
In a separate experiment, mixed ovarian cells were isolated from another set
of normally cycling rats and directly challenged with embelin in vitro.
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Results from theses studies revealed that embelin also suppresses estradiol
and progesterone secretion by isolated mixed ovarian cells.
These data demonstrate that embelin suppresses plasma estradiol and
progesterone levels; disrupts the evolution of the regular oestrous cycles and
also affects ovarian morphology in rats. The results further demonstrate that
embelin probably exerts its effects by acting directly on ovarian cells. | en |
