Comparative Studies on the Modulatory Effect of Pomegranate Juice and Risedronate Sodium on Bone Turnover in Ovariectomized Adult Rats

Abstract

Objective: Osteoporosis is a disease characterized by disruption of trabecular bone structure and loss of mineralized bone, which increase the risk of fracture. Estrogen deficiency is a critical factor that leads to bone loss in women. The present study was carried out to investigate the effects of oral administration of pomegranate juice and risedronate sodium (Actonel) alone or in combination on ovariectomy rats for two months. Design: the current study was conducted on 126 adult female Sprague Dawley rats divided into seven groups n=18 as follows: Gp. (1) (sham) : operated control, Gp. (2) (ovx): rats were underwent surgery to remove ovaries, Gp. (3) (Movx): ovariectomized rats received pomegranate juice orally in a dose of (3ml/kg/day) ,Gp. (4) (Rovx): ovariectomized rats received risedronate sodium (Actonel) orally in a dose of (3mg/kg/week) , Gp. (5) (Movx+ Rovx): ovariectomized rats treated with both orally pomegranate juice and risedronate sodium, Gp. (6) (Msham): sham operated control group received pomegranate juice Gp. (7) (Rsham): sham operated control group received risedronate sodium. At the end of the experiment rats were sacrificed and serum was collected from different groups at 2, 4 and 8 weeks. In addit ion, femur and tibia bones were obtained. Results: ovariectomized group (ovx) showed significant decrease in serum estradiol (E2), progesterone and calcitonin (CT); and a significant increase in serum parathyroid hormone (PTH), total calcium (Ca), ionized (Ca2+), phosphorus (P), albumin (Alb) and enzymatic activity of serum alkaline phosphatase (ALP) in a time dependent manner compared with control. Moreover, bone mineral density (BMD) and bone density of both femur and tibia showed significant decrease. Taken together these parameters are reflecting a high rate of bone turnover. However, the treatment of pomegranate juice induced a remarkable improvement in the tested parameters as indicated by a significant increase in BMD, bone density of femur and tibia in comparison to (ovx) group While, the administration of risedronate sodium minimized the harmful effect of ovariectomy in some tested parameters, but not reflected significant change in (BMD), bone density and female sex hormones. Conclusion: The present study showed that pomegranate juice inhibits ovariectomy induced bone loss in female rats due to its rich content of polyphenols and estrogens.