Advanced oxidation protein products accelerated the bone loss and weakened bone strength in ovariectomised rats

Advanced oxidation protein products (AOPPs) are prevalent in several kinds of disorders. Previous research revealed that the levels of AOPPs in postmenopausal women were significantly higher than that in premenopausal women. Whether AOPPs have any effect on bone loss remains unclear. Our research analysed the role of AOPPs on the development of osteoporosis in ovariectomised (OVX) rats.

Female SD rats were divided into five groups (SHAM, OVX+PBS, OVX+RSA (Rat Serum Albumin), OVX+AOPPs, OVX+AOPPs+SOD) and subjected to sham or ovariectomy. PBS, RSA, and AOPPs were injected daily with or without intragastric administration of superoxide dismutase (SOD) after surgery. Every 4 weeks blood and the tibia were harvested from eight rats in each group. The expression of osteocalcin and CTX-I (C-terminal crosslinking telopeptide of type I collagen) in serum was measured by ELISA, and the tibiae were subjected to metaphyseal three-point bending and μCT analysis.

AOPPs increased the serum level of osteocalcin and CTX-I. μCT showed AOPPs decreased bone mass at week 4 and week 8, while significant differences in F_max and energy absorption were found between the PBS and AOPPs groups at week 20 and week 24. No significant differences were found between the AOPPs and AOPPs+SOD groups at any time.

AOPPs accelerated the bone loss and weakened bone strength in OVX rats.