Less mechanical loading attenuates osteoarthritis by reducing cartilage degeneration, subchondral bone remodelling, secondary inflammation, and activation of NLRP3 inflammasome

Bone & Joint Research

article

Zhennian He¹  Pengfei Nie¹  Jianli Lu²  Yong Ling¹  Jian Guo¹  Bin Zhang¹  Jianghua Hu¹  Jiawei Liao¹  Jie Gu¹  Bo Dai¹  Zhiyun Feng² 

[1] Department of Orthopedic Surgery, Beilun District People’s Hospital;Department of Orthopedic Surgery, The First Affiliated Hospital, School of Medicine, Zhejiang University

关键词: Osteoarthritis;    Cartilage destruction;    Mechanical loading;    NLRP3 inflammasome;    Subchondral bone;   

DOI  :  10.1302/2046-3758.910.BJR-2019-0368.R2

学科分类：骨科学

来源: British Editorial Society Of Bone And Joint Surgery

【 摘 要 】

AimsOsteoarthritis (OA) is a disabling joint disorder and mechanical loading is an important pathogenesis. This study aims to investigate the benefits of less mechanical loading created by intermittent tail suspension for knee OA.MethodsA post-traumatic OA model was established in 20 rats (12 weeks old, male). Ten rats were treated with less mechanical loading through intermittent tail suspension, while another ten rats were treated with normal mechanical loading. Cartilage damage was determined by gross appearance, Safranin O/Fast Green staining, and immunohistochemistry examinations. Subchondral bone changes were analyzed by micro-CT and tartrate-resistant acid phosphatase (TRAP) staining, and serum inflammatory cytokines were evaluated by enzyme-linked immunosorbent assay (ELISA).ResultsOur radiographs showed that joint space was significantly enlarged in rats with less mechanical loading. Moreover, cartilage destruction was attenuated in the less mechanical loading group with lower histological damage scores, and lower expression of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-5, matrix metalloproteinase (MMP)-3, and MMP-13. In addition, subchondral bone abnormal changes were ameliorated in OA rats with less mechanical loading, as reduced bone mineral density (BMD), bone volume/tissue volume (BV/TV), and number of osteophytes and osteoclasts in the subchondral bone were observed. Finally, the level of serum inflammatory cytokines was significantly downregulated in the less mechanical loading group compared with the normal mechanical loading group, as well as the expression of NACHT, LRR, and PYD domains-containing protein 3 (NLRP3), caspase-1, and interleukin 1β (IL-1β) in the cartilage.ConclusionLess mechanical loading alleviates cartilage destruction, subchondral bone changes, and secondary inflammation in OA joints. This study provides fundamental insights into the benefit of non-weight loading rest for patients with OA.

【 授权许可】

CC BY-NC