Remodelling parameters at subchondral bone and systemic level. (a)Alkaline hosphatise (ALP) and metalloproteinase 9 (MMP9) protein expressions at subchondral bone. At top: Densitometric analysis of ALP and MMP9 protein expressions at subchondral bone. At bottom: representative Western Blot images of ALP and MMP9 for 40 μg of total subchondral bone protein. The number of samples assayed for ALP expression were: HEALTHY n = 10; OA n = 8; OP n = 8 and OPOA n = 10, and for MMP9 were: n = 6 in each group. OA, osteoarthritis; OP, osteoporosis (b)Enzymatic activity for ALP and tartrato-resistant alkaline phosphatase (TRAP) in serum from OP animals (OP and OPOA groups; n = 8; white bars) and non-OP animals (healthy and OA groups; n = 7; black bars). OA, osteoarthritis; OP, osteoporosis. Bar represents the mean ± SEM. *P < 0.05 vs. HEALTHY, #P < 0.05 vs. OA.