PMID- 34988207
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20220429
IS  - 2305-5839 (Print)
IS  - 2305-5847 (Electronic)
IS  - 2305-5839 (Linking)
VI  - 9
IP  - 22
DP  - 2021 Nov
TI  - Role of the Alarmin S100A9 protein in inducing Achilles tendinopathy in rats.
PG  - 1698
LID - 10.21037/atm-21-5945 [doi]
LID - 1698
AB  - BACKGROUND: This study aimed to investigate the correlation between the Alarmin 
      S100A9 protein and Achilles tendinopathy (AT), and to reveal the role of this 
      protein in inducing AT. METHODS: In this study, 40 male Sprague-Dawley rats were 
      randomly divided into four groups: Control group (received no treatment), Injury 
      group (Achilles tendon tissues were cut intraoperatively), S100A9 group (received 
      a subcutaneous injection of rhS100A9 solution), and S100A9 + Paquinimod group 
      [received a subcutaneous injection of rhS100A9 and Paquinimod (1:1 ratio) into 
      the Achilles tendon]. At 1 week postoperatively, the four groups of rats were 
      euthanized, and the Achilles tendon tissues were isolated for histological 
      staining, immunohistochemistry (IHC), immunofluorescence, Sirius Red (SR) 
      staining, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end 
      labeling assay. RESULTS: Compared with both the Control and S100A9 + Paquinimod 
      groups, the Injury and S100A9 groups exhibited higher expression levels of S100A9 
      protein, matrix metalloproteinase-3 (MMP-3), and inflammatory factors. Regarding 
      histomorphology [hematoxylin-eosin (HE) staining and Safranin O/fast green (SOFG; 
      fast green and Safranin) training], the Achilles tendon tissues in the Injury and 
      S100A9 groups showed AT-like changes, and the fibers were extremely disorderly, 
      non-bundled, and ruptured, and some nuclei were spindles. As for collagen (Col) 
      remodeling, a large number of fresh collagen fibers had formed, the amounts of 
      Col-I and Col-II were lower, and a large quantity of Col-III was present. 
      Additionally, a large number of tendon cells had died in both the Injury and 
      S100A9 groups. CONCLUSIONS: This study showed that Alarmin S100A9 can induce 
      AT-like morphological changes and local inflammatory reactions, trigger collagen 
      fiber remodeling and tendon cell apoptosis, and ultimately induce AT.
CI  - 2021 Annals of Translational Medicine. All rights reserved.
FAU - Zhao, Bin-An
AU  - Zhao BA
AD  - Department of Orthopedics, Shanghai Tenth People's Hospital, School of Medicine, 
      Tongji University, Shanghai, China.
FAU - Li, Jun
AU  - Li J
AD  - Department of Orthopedics, Shanghai Tenth People's Hospital, School of Medicine, 
      Tongji University, Shanghai, China.
FAU - Xue, Chao
AU  - Xue C
AD  - Department of Orthopedics, Shanghai Tenth People's Hospital, School of Medicine, 
      Tongji University, Shanghai, China.
FAU - Li, Jie
AU  - Li J
AD  - Department of Orthopedics, Shanghai Zhabei District Central Hospital, Shanghai, 
      China.
FAU - Ge, Heng-An
AU  - Ge HA
AD  - Department of Orthopedics, Shanghai Tenth People's Hospital, School of Medicine, 
      Tongji University, Shanghai, China.
FAU - Cheng, Biao
AU  - Cheng B
AD  - Department of Orthopedics, Shanghai Tenth People's Hospital, School of Medicine, 
      Tongji University, Shanghai, China.
FAU - Su, Qi-Hang
AU  - Su QH
AD  - Department of Orthopedics, Shanghai Tenth People's Hospital, School of Medicine, 
      Tongji University, Shanghai, China.
LA  - eng
PT  - Journal Article
PL  - China
TA  - Ann Transl Med
JT  - Annals of translational medicine
JID - 101617978
PMC - PMC8667095
OTO - NOTNLM
OT  - Achilles tendinopathy (AT)
OT  - Alarmin S100A9
OT  - animal experiment
OT  - degeneration
OT  - inflammation
COIS- Conflicts of Interest: All authors have completed the ICMJE uniform disclosure 
      form (available at https://dx.doi.org/10.21037/atm-21-5945). The authors have no 
      conflicts of interest to declare.
EDAT- 2022/01/07 06:00
MHDA- 2022/01/07 06:01
PMCR- 2021/11/01
CRDT- 2022/01/06 06:00
PHST- 2021/10/09 00:00 [received]
PHST- 2021/11/19 00:00 [accepted]
PHST- 2022/01/06 06:00 [entrez]
PHST- 2022/01/07 06:00 [pubmed]
PHST- 2022/01/07 06:01 [medline]
PHST- 2021/11/01 00:00 [pmc-release]
AID - atm-09-22-1698 [pii]
AID - 10.21037/atm-21-5945 [doi]
PST - ppublish
SO  - Ann Transl Med. 2021 Nov;9(22):1698. doi: 10.21037/atm-21-5945.