Effect of Diet with Dried Plum, Calcium and Vitamin D on Osteoporosis in Ovariectomized Rats

The study aimed to assess the protective effect of diet supplemented with dried plum powder (DPP), calcium (Ca) and vitamin D (Vit.D) on osteoporosis in ovariectomized (OVX) rats and to elucidate the potential mechanisms. Forty two Sprague Dawley rats were randomized into 6 equal groups (n= 7). Group 1 was SHAM- operated (negative control), while the other 5 groups were OVX-operated. Three weeks post-ovariectomy, group 2 was kept positive control (OVX) and fed on basal diet. Groups 3, 4, 5 and 6 were fed on diets supplemented with DPP, Ca, Vit.D and DPP + Ca + Vit.D, respectively for 6 weeks. At the end of experiment, rats were weighted and blood samples were collected for estimating serum biomarkers of osteoporosis. Rats were then sacrificed and uteri were dissected out and weighed. Femur bones were dissected out for estimating bone markers of osteoporosis. The results showed that feeding diets supplemented with DPP + Ca + Vit.D reversed the increase in body weight gain and the decrease in uterine weight induced by ovariectomy. It also significantly increased serum calcium (Ca), bone-specific alkaline phosphatase (b-ALP) and osteocalcin (OC) but decreased serum interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and pyridinoline (PD) levels in OVX-rats. There were significant increases in serum free thyroxin (T4) and calcitonin (CT) hormones and a decreased in parathormone (PTH). Femur bone mineral density (BMD) and contents of calcium and phosphorus in bone ash were also increased. These findings suggest that feeding of OVX rats on diets supplemented with dried plum, calcium and Vit. D together induces an anti-osteoporotic effect. This effect might be due to enhancement of bone formation, suppression of bone loss and regulation of some metabolic hormones which control calcium. Therefore, intake of dried plum and consumption of foods rich in calcium (as milk and dairy products) and Vit.D may be beneficial for the prevention of osteoporosis in postmenopausal women.