| Objective To investigate the effect of vitamin K2 on bone mineral density, bone metabolism, and serum cathepsin K (Cathe K) in postmenopausal women with osteoporosis. Methods A total of 120 postmenopausal osteoporosis patients who met the inclusion criteria from May 2014 to January 2016 in our hospital were enrolled. The patients were randomly divided into vitamin K2 group, strontium ranelate group, and blank control group (N=40 in each group). Patients in strontium ranelate group received 2g of strontium ranelate daily. Patients in vitamin K2 group received 15mg of menatetrenone soft capsules each time, 3 times a day. BMD of the hip and lumbar spine were measured before and 6 months after drug treatment. The levels of serum osteocalcin (BGP), β-collagen degradation products (β-crosslaps), type I procollagen amino terminal propeptide (PINP), tartrate-resistant acid phosphatase (TRAP), and Cathe K were measured. Results BMD, bone metabolism, and Cathe K changed in each group after the treatment. Compared with that in the control group, BMD of the hip and lumbar spine in vitamin K2 group and strontium ranelate group increased in varying degree, and it was more obvious and statistically significant in strontium ranelate group (P<0.05). Strontium ranelate group showed lowest osteoclastic activity (β-crosslaps, TRAP) and higher osteogenic activity (BGP, PINP). Vitamin K2 group showed decreased activity of osteoclasts (β-crosslaps, TRAP) and increased osteogenic activity (BGP, PINP). There was statistically different among the groups (P<0.05). Comparing to that in other groups, Cathe K in strontium ranelate group decreased most significantly, with statistically significance (P<0.05). Conclusion Vitamin K2 improves BMD of the hip and lumbar spine in postmenopausal women by promoting osteogenic activity and decreasing osteoclastic activity and Cathe K expression. |