gms | German Medical Science

14th Triennial Congress of the International Federation of Societies for Surgery of the Hand (IFSSH), 11th Triennial Congress of the International Federation of Societies for Hand Therapy (IFSHT)

17.06. - 21.06.2019, Berlin

Aging Affects Tenogenic and Chondrogenic Gene Expression in Mouse Intrasynovial Tendons

Meeting Abstract

  • presenting/speaker Masanori Hayashi - Department of Orthopaedic Surgery, Shinshu University, Matsumoto, Japan
  • Hiroko Iwakawa - Department of Orthopaedic Surgery, Shinshu University, Matsumoto, Japan
  • Yo Kitamura - Department of Orthopaedic Surgery, Shinshu University, Matsumoto, Japan
  • Shigeharu Uchiyama - Department of Orthopaedic Surgery, Okaya City Hospital, Okaya, Japan
  • Hiroyuki Kato - Department of Orthopaedic Surgery, Shinshu University, Matsumoto, Japan

International Federation of Societies for Surgery of the Hand. International Federation of Societies for Hand Therapy. 14th Triennial Congress of the International Federation of Societies for Surgery of the Hand (IFSSH), 11th Triennial Congress of the International Federation of Societies for Hand Therapy (IFSHT), 11th Triennial Congress of the International Federation of Societies for Hand Therapy (IFSHT). Berlin, 17.-21.06.2019. Düsseldorf: German Medical Science GMS Publishing House; 2020. DocIFSSH19-370

doi: 10.3205/19ifssh0270, urn:nbn:de:0183-19ifssh02707

Published: February 6, 2020

© 2020 Hayashi et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. See license information at http://creativecommons.org/licenses/by/4.0/.


Outline

Text

Objectives/Interrogation: It is well known that aging alters the musculoskeletal system, resulting in tissue degeneration and age-associated injury and disease. Tenosynovitis is also considered to be an age-associated intrasynovial tendon disease. However, little is known about the pathogenic mechanism of tenosynovitis and its relation to tendon degeneration during the aging process. Senescence accelerated mouse (SAM) P6, a strain with low peak bone density, is an osteoporosis and senescence model mouse. The purpose of this study is to investigate age-related changes in SAMP6 mouse intrasynovial tendon.

Methods: Eighty hind paws were obtained from forty mice: ten 8-week SAMR1 mice, ten 8-week SAMP6 mice, ten 24-week SAMR1 mice, and ten 24-week SAMP6 mice. SAMR1 mice were used as controls for SAMP6 mice. The right side hind paws of each mouse were used for real-time PCR. Relative expression levels of scleraxis, tenomodulin, collagen type I, Sox9, Sox5, Sox6, and aggrecan were compared. The left side hind paws were used for histological analyses and immunohistochemical analyses with anti-tenomodulin and anti-aggrecan antibody.

Results and Conclusions: Gene expression analysis for tenogenic marker showed decreased expression of tenomodulin and collagen type I and slightly increased expression of scleraxis in DDF tendons of 24-week SAMR1 and SAMP6 mice compared with 8-week SAMR1 and SAMP6 mice. There was no statistical difference between SAMR1 and SAMP6 in each week. Analysis for chondrogenic marker showed that Sox9 and Sox6 expression in DDF tendons of SAMP6 was higher than in SAMR1 in both 8- and 24-week mice. The expressions of Sox5 and aggrecan were higher in 8-week SAMP6 mice than in SAMR1 mice and increased in 24-week SAMR1 mice.

Histological analysis showed no changes in DDF tendon and surrounding tissues of both 8- and 24-week SAMP6 and SAMR1 mice. Immunohistochemical analysis showed the expression of tenomodulin was reduced in DDF tendons of 24-week SAMR1 and SAMP6 mice compared with 8-week SAMR1 and SAMP6 mice. The trend was much stronger in SAMP6 than in SAMR1 mice. Immunostaining of aggrecan showed no difference between 8- and 24-week SAMP6 and SAMR1 mice.

This study demonstrates decreased expression of tenogenic marker and increased expression of chondrogenic marker in intrasynovial tendon with aging. Chondroid metaplasia has also been found in the A1 pulley in adult trigger fingers (Sbernardori et al., 2007). This may be associated with the pathogenesis of tendon degeneration and tenosynovitis.