Effects of bisphosphonates on bone metabolism and serum matrix metalloproteinase level in patients with ankylosing spondylitis secondary osteoporosis

The aim of the study is to investigate the effects of bisphosphonates on bone metabolism and serum matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-3 (MMP-3) levels in patients with ankylosing spondylitis (AS) secondary osteoporosis. 60 patients with AS secondary osteoporosis were divided into treatment group and control group. The control group was given conventional treatment of oral calcium D-dimensional, while the treatment group was given combination therapy of conventional treatment, technetium methylene bisphosphonate and alendronate. The MMP-2, MMP-3, bone alkaline phosphatase (BALP), tartrate resistant acid phosphatase 5b (TRACP-5b) and Vitamin D receptors (VDR) levels were measured. After administration, the serum MMP-2, MMP-3 and TRACP-5b levels in treatment group significantly decreased, while compared with pretreatment, the difference were also significant, respectively (t = 7.371, 7.197 and 4.984, p<0.05). Compared with the control group, the serum MMP-2, MMP-3 and TRACP-5b levels in treatment group significantly decreased (t=5.745, 5.311 and 3.761, p<0.05). After adminstration, the serum BALP and VDR levels in treatment group significantly increased, while compared with pretreatment, the differences were significant, respectively (t=4.890 and 4.376, p<0.05). Compared with the control group, the serum BALP and VDR levels in treatment group significantly increased (t=3.490 and 3.634, P<0.05). The pretreatment serum MMP-2, MMP-3 and TRACP5b levels had significant positive correlations (r=0.478 and 0.513, p<0.05), while BALP and VDR levels had negative correlations (r=-0.512, -0.492 and -0.563, -0.495, p<0.05). Conclusively, bisphosphonates can inhibit bone resorption and promote bone formation in AS secondary osteoporosis patients by decreasing MMP-2, MMP-3 and TRACP-5b levels and increasing BALP and VDR levels.