Supplementation of Safflower Seed Powder and Extracts Enhances Bone Metabolism in Rib-Fractured Rats

Abstract

The current study investigated the effect of Korean safflower (Carthamus tinctorius L.) seed powder, its water, ethanol extracts on bone metabolism during recovery from rib-fracture induced by surgical operation in rats. 10-week-old male Sprague-Dawley rats weighing about 320 g were divided into 9 groups after arrival: 10d control (AIN 76 semi-purified diet), 10d safflower seed powder (10d SS-powder), 10d safflower seed ethanol extract (10d SS-EtOH), 10d safflower seed water extract (10d SS-H2O), 20d control (AIN-76 semi-purified diet), 20d safflower seed powder (20d SS-powder), 20d safflower seed ethanol extract (20d SS-EtOH), 20d safflower seed water extract (20d SS-H2O),, 20d sham-operation (20d sham). The dietary level for all the supplements was 5% based on the raw material weight. The rats were fed the experimental diets for 10 days before the rib fracture operation, for a further 10 or 20 days after the operation. A number 9 rib was fractured surgically, a sham-operation also performed. The rats were then sacrificed on the 10th or 20th day after the operation. The body weight initially decreased after the operation in all the rib-fractured groups, then gradually recovered. The concentrations of plasma osteocalcin were higher in the control group than in all the safflower-supplemented groups 10, 20 days after the rib-fracture (p＜0.05). The bone-specific ALP (alkaline phosphatase) activity was significantly higher in the SS-EtOH group than in the other groups 20 days after the rib-fracture (p＜0.05). The level of urinary DPD (deoxypridinoline) was significantly higher in the SS-EtOH, SS-H₂O groups than in the other groups 10 days after the rib-fracture. When comparing the PTH (parathyroid hormone), calcitonin levels, the SS-H₂O group exhibited the highest PTH level among the groups 10, 20 days after the rib-fracture. Thus, it was concluded that the bone turnover during the fracture-healing period was more rapid in the rats supplemented with safflower seed powder or its fractions than in the control rats. Furthermore, the SS-H₂O fraction was identified as the most effective in stimulating bone remodeling, as bone resorption, bone formation were both significantly increased during fracture healing when compared to the control group.