Tawaratsumida H, Iuchi T, Masuda Y, Ide T, Maesako S, Miyazaki T, Ijuin T, Maeda S, Taniguchi N . Zoledronate alleviates subchondral bone collapse and articular cartilage degeneration in a rat2024 · 記述言語： 英語 出版者・発行元： Osteoarthritis and Cartilage Objective: To evaluate the humeral head bone volume of patients with cuff tear arthropathy (CTA) and examine the therapeutic effect of zoledronate in a rat modified model of CTA (mCTA). Design: The bone mass in patients with CTA was measured using Hounsfield units from CT images. The mCTA was induced by transecting the rotator cuff, biceps brachii tendon, and superior half of the joint capsule in adult rat shoulders. A single subcutaneous injection of zoledronate was followed by bone histomorphometry and immunohistochemistry of the humeral head, as well as the Murine Shoulder Arthritis Score (MSAS) assessment. Results: The humeral head bone volume was decreased in patients with CTA. In the mCTA model, M1 macrophages were increased in the synovium and were decreased by zoledronate treatment. The increased expressions of TNF-α, IL-1β and IL-6 in mCTA synovium and articular cartilage were suppressed in the zoledronate-treated mCTA group. The expression of catabolic enzymes in the articular cartilage and MSAS showed similar results. The zoledronate-treated mCTA group showed a decreased subchondral bone collapse with a decreased RANKL/OPG expression ratio and a suppressed number of osteoclasts compared with the control mCTA group. The enhanced expressions of HMGB1 and S100A9 in the mCTA shoulders were eliminated in the zoledronate-treated mCTA group. Conclusions: The humeral head subchondral bone was decreased in patients with CTA. In the mCTA model, the collapse and osteoarthritic changes were prevented by zoledronate administration. Zoledronate seemed to suppress the number of M1 macrophages in the synovium and osteoclasts in the subchondral bone. DOI： 10.1016/j.joca.2024.08.005 Scopus PubMed
Ijuin T, Iuchi T, Tawaratsumida H, Masuda Y, Tokushige A, Maeda S, Taniguchi N . Development of a novel animal model of rotator cuff tear arthropathy replicating clinical features of progressi2023 · 記述言語： 英語 出版者・発行元： Osteoarthritis and Cartilage Open Objective: To establish an animal model of modified cuff tear arthropathy (mCTA) in order to better replicate the pathophysiology associated with rotator cuff tear-induced humeral head collapse. Design: mCTA was induced by transection of the rotator cuff, the long head of the biceps brachii (LHB), and superior half of the joint capsule in the right shoulder of 12-week-old rats; the left shoulder underwent sham surgery. The severity of CTA was quantitated using the Murine Shoulder Arthritis Score (MSAS). The trabecular bone of the humeral head and metaphysis was analyzed using bone histomorphometry. The expression of proinflammatory cytokines and catabolic enzymes was evaluated immunohistochemically. Results: In the mCTA model, the MSAS increased starting from 2 weeks after induction, and there was notable subchondral bone collapse with fibrous cells at 4 weeks. The mCTA cartilage exhibited positive staining for TNF-α, IL-1β/6, MMP-3/13, and ADAMTS5. The trabecular bone volume was reduced not only in the subchondral bone but also in the metaphysis of the humeri, and bone resorption was enhanced in these areas. In the collapsed subchondral bone, both bone formation and resorption were increased. The fibrous cells showed expression of TNF-α, IL-6, and MMP-13, along with specific markers of mesenchymal stem cells. Furthermore, the fibrous cells showed osteoblastic characteristics (RUNX2-positive) and expressed RANKL. Conclusions: The LHB and the capsuloligamentous complex are critical stabilizers of the glenohumeral joint, serving to prevent the advancement of CTA following massive rotator cuff tears. Fibrous cells appear to play a role in the humeral head bone resorption. DOI： 10.1016/j.ocarto.2023.100389 Scopus PubMed
