Evaluation of estrogen-like activity of Nigella sativa in ovariectomized rats

Abstract

The purpose of the current study was to evaluate estrogenic activity of Nigella sativa using ovariectomized 
(OVX) rats. Forty OVX rats divided into five groups. N. sativa was administered orally as a supplement to 
chaw palate at different doses of 300, 600 and 1200 mg/kg for 21 days to OVX rats and were compared to 
either positive (0.2 mg/kg conjugated equine estrogen- CEE) or negative control (1 ml distilled water). 
Histopathological changes of the rats’ uterus such as epithelial proliferation and endometrial glandular 
hyperplasia were assessed as well as uterus weight and serum estradiol level. Supplementation with N. 
sativa resulted in a significant increase in uterine weight as compared to the OVX controls accompanied by 
altering the serum estrogen levels. Histopathological evaluation of the uterine section revealed changes 
characterized by atrophy of the uterus in the OVX controls, while the OVX rats supplemented with N. sativa 
showed increased endometrial response as indicated by proliferation of the endometrial glands and epithelial 
hyperplasia as well as epithelial proliferation and endometrial glandular hyperplasia. The effects of N. sativa 
were comparable to that in the CEE group. N. sativa showed the desired effects on the physical, histological 
and biochemical parameters of the uterine tissue in OVX rats, thereby indicating its probable beneficial role 
in the treatment of postmenopausal symptoms.