1. Academic Validation
  2. The Effects of NF-κB Suppression on the Early Healing Response Following Intrasynovial Tendon Repair in a Canine Model

The Effects of NF-κB Suppression on the Early Healing Response Following Intrasynovial Tendon Repair in a Canine Model

  • J Orthop Res. 2023 Apr 24. doi: 10.1002/jor.25576.
Ryan A Lane 1 Nicole Migotsky 1 2 Necat Havlioglu 3 Leanne E Iannucci 2 Hua Shen 1 Spencer Lake 4 Shelly E Sakiyama-Elbert 5 Stavros Thomopoulos 6 7 Richard H Gelberman 1
Affiliations

Affiliations

  • 1 Department of Orthopaedic Surgery, Washington University, St Louis, Missouri, USA.
  • 2 Department of Biomedical Engineering, Washington University, St Louis, Missouri, USA.
  • 3 Department of Pathology, John Cochran VA Medical Center, St Louis, Missouri, USA.
  • 4 Mechanical Engineering & Materials Science, Washington University, St Louis, Missouri, USA.
  • 5 Department of Biomedical Engineering, Washington University, Seattle, Washington, USA.
  • 6 Department of Orthopaedic Surgery, Columbia University, New York, New York, USA.
  • 7 Department of Biomedical Engineering, Columbia University, New York, New York, USA.
Abstract

The highly variable clinical outcomes noted after intrasynovial tendon repair have been associated with an early inflammatory response leading to the development of fibrovascular adhesions. Prior efforts to broadly suppress this inflammatory response have been largely unsuccessful. Recent studies have shown that selective inhibition of IKK-β, an upstream activator of NF-κB signaling, mitigates the early inflammatory response and leads to improved tendon healing outcomes. In the current study, we test the hypothesis that oral treatment with the IKK-β Inhibitor ACHP (2-amino-6-[2-(cyclopropylmethoxy)-6-hydroxyphenyl]-4-piperidin-4-yl nicotinenitrile an inhibitor) will modulate the post-operative inflammatory response and improve intrasynovial flexor tendon healing. To test this hypothesis, the flexor digitorum profundus tendon of 21 canines was transected and repaired within the intrasynovial region and assessed after 3 and 14 days. Histomorphometry, gene expression analyses, immunohistochemistry, and quantitative polarized LIGHT imaging (QPLI) were used to examine ACHP-mediated changes. ACHP led to reduction in phosphorylated p-65, indicating that NF-κB activity was suppressed. ACHP enhanced expression of inflammation-related genes at 3 days and suppressed expression of these genes at 14 days. Histomorphometry revealed enhanced cellular proliferation and neovascularization in ACHP-treated tendons compared to time-matched controls. These findings demonstrate that ACHP effectively suppressed NF-κB signaling and modulated early inflammation, leading to increased cellular proliferation and neovascularization without stimulating the formation of fibrovascular adhesions. Together, these data suggest that ACHP treatment accelerated the inflammatory and proliferative phases of tendon healing following intrasynovial flexor tendon repair. This article is protected by copyright. All rights reserved.

Keywords

ACHP; Canine; IKK-β; Inflammation; Intrasynovial Flexor Tendon Repair; NF-κB.

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