The Effects of Hydroalcoholic Extract of Nigella sativa Seeds on Serum Estradiol and Prolactin Levels and obstetric Criteria due to Hypothyroidism in Rat

The aim of this study was investigation of the effects of Nigella sativa (NS) seeds on hypothyroid pregnant rats and their progenies.

Hypothyroidism was induced by propylthiouracil (PTU) 0.03% in drinking water. Female rats were divided into seven groups: control, PTU, PTU‑NS (100, 200, and 400 mg/kg), and NS (100 and 400 mg/kg). All treatments were done 20 days before mating and during pregnancy. The weight of rat dams and progenies, number of progenies and serum T4, estradiol and prolactin (PRL) levels in rat dams were measured for all groups.

Serum T4 in all PTU‑NS groups before mating was significantly increased versus PTU group. Body weight of rat dams before mating in all groups of PTU‑NS was increased versus PTU group by P < 0.001, P < 0.05, and P < 0.001, respectively and in NS 100 and NS 400 was increased versus control group (P < 0.001). The number of offspring was significantly decreased in PTU and PTU‑NS versus control group. The weight of progenies in NS 400 was higher than control group (P < 0.001) and was increased in PTU‑NS 200 and PTU‑NS 400 versus PTU group by P < 0.001 and P < 0.05, respectively. Serum PRL level in rat dams in control, PTU, and PTU‑NS groups were not statistically different between groups but significantly increased in NS 400 group when compared to control group. Estradiol levels were not significantly different in rat dams at 5 days after delivery.

These results demonstrated that feeding of rat dams with NS extract before mating has positive protective effects on progenies. These effects may be due to antioxidant properties of NS in reducing oxidative stress and thyroid damages induced by PTU.