{"title":"Therapeutic effect of C-type natriuretic peptide on persistent pain in a rat knee arthritis model.","authors":"Shoichi Hasegawa, Jae-Sung An, Jun Hino, Yusuke Amano, Yusuke Nakagawa, Kazumasa Miyatake, Hiroki Katagiri, Tomomasa Nakamura, Ichiro Sekiya, Hideyuki Koga, Kunikazu Tsuji","doi":"10.1177/10225536231181708","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Intra-articular injection of C-type natriuretic peptide (CNP) at the acute inflammatory stage suppressed fibrotic changes in the infrapatellar fat pad (IFP), articular cartilage degeneration, and persistent pain in a monoiodoacetic acid (MIA)-induced rat knee arthritis model. In this study, we administered CNP during the inflammation subsiding period to evaluate CNP effectiveness in knees with osteoarthritis (OA) pathology.</p><p><strong>Methods: </strong>20 male Wistar rats were randomly divided into two groups. The rats received an intra-articular injection of MIA solution in the right knee to induce inflammation-induced joint degeneration. One group subsequently received an intra-articular CNP injection for six consecutive days from day 8, whereas another group received vehicle solution. Pain avoidance behavior tests and histological analyses were conducted to examine the therapeutic effects of CNP.</p><p><strong>Results: </strong>The incapacitance test indicated that the percent weight on the ipsilateral limb decreased after MIA injection by day 4 and continued to decrease until the end of the experiment in the vehicle group, suggesting persistent pain in the knee. Intra-articular injection of CNP reversed the weight-bearing ratio on day 19. Histological evaluation showed that the CNP group had more residual fat tissue in the IFP and fewer calcitonin gene-related peptide-positive nerve endings compared to the vehicle group. CNP could not reverse articular cartilage degeneration.</p><p><strong>Conclusions: </strong>Intra-articular injection of CNP after the IFP fibrosis onset had no significant effect on OA severity and extent. Nevertheless, CNP might be utilized therapeutically for OA treatment since it can alleviate persistent knee pain and inhibit structural changes in residual fat tissue.</p>","PeriodicalId":48794,"journal":{"name":"Journal of Orthopaedic Surgery","volume":null,"pages":null},"PeriodicalIF":1.3000,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Orthopaedic Surgery","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1177/10225536231181708","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ORTHOPEDICS","Score":null,"Total":0}
引用次数: 0
Abstract
Background: Intra-articular injection of C-type natriuretic peptide (CNP) at the acute inflammatory stage suppressed fibrotic changes in the infrapatellar fat pad (IFP), articular cartilage degeneration, and persistent pain in a monoiodoacetic acid (MIA)-induced rat knee arthritis model. In this study, we administered CNP during the inflammation subsiding period to evaluate CNP effectiveness in knees with osteoarthritis (OA) pathology.
Methods: 20 male Wistar rats were randomly divided into two groups. The rats received an intra-articular injection of MIA solution in the right knee to induce inflammation-induced joint degeneration. One group subsequently received an intra-articular CNP injection for six consecutive days from day 8, whereas another group received vehicle solution. Pain avoidance behavior tests and histological analyses were conducted to examine the therapeutic effects of CNP.
Results: The incapacitance test indicated that the percent weight on the ipsilateral limb decreased after MIA injection by day 4 and continued to decrease until the end of the experiment in the vehicle group, suggesting persistent pain in the knee. Intra-articular injection of CNP reversed the weight-bearing ratio on day 19. Histological evaluation showed that the CNP group had more residual fat tissue in the IFP and fewer calcitonin gene-related peptide-positive nerve endings compared to the vehicle group. CNP could not reverse articular cartilage degeneration.
Conclusions: Intra-articular injection of CNP after the IFP fibrosis onset had no significant effect on OA severity and extent. Nevertheless, CNP might be utilized therapeutically for OA treatment since it can alleviate persistent knee pain and inhibit structural changes in residual fat tissue.
期刊介绍:
Journal of Orthopaedic Surgery is an open access peer-reviewed journal publishing original reviews and research articles on all aspects of orthopaedic surgery. It is the official journal of the Asia Pacific Orthopaedic Association.
The journal welcomes and will publish materials of a diverse nature, from basic science research to clinical trials and surgical techniques. The journal encourages contributions from all parts of the world, but special emphasis is given to research of particular relevance to the Asia Pacific region.