Prophylactic Effects of NFκB Essential Modulator-Binding Domain Peptides on Bone Infection: An Experimental Study in a Rabbit Model

J Inflamm Res. 2022 Apr 28:15:2745-2759. doi: 10.2147/JIR.S346627. eCollection 2022.

Abstract

Introduction: Osteomyelitis is characterized by intensive inflammatory bone disease and remains a clinical challenge in orthopedic surgery, despite the advances made in medical and surgical therapies. Staphylococcus aureusis a major causative agent of osteomyelitis, causing the progressive inflammatory destruction of bone. Prophylaxis of osteomyelitis during orthopedic surgery is necessary. NFκB essential modulator-binding domain (NBD) peptides are cell-permeable peptide inhibitors of the IκB-kinase complex. The prophylactic effect of NBD peptides in relieving inflammation and inhibiting bone defects in osteomyelitis is still under investigation. Our purpose was to determine the preventive effect of NBD peptides in S. aureus infection-induced bone defects in osteomyelitis.

Methods: An S. aureus osteomyelitis rabbit model was used in this study. The rabbits were divided into four groups: NBD, cefazolin, control, and PBS. Clinical and laboratory indicators of erythrocyte-sedimentation rate, CRP, and TNFα levels were assessed to monitor systemic reactions. The efficacy of NBD peptides in S. aureus-induced osteomyelitis was evaluated by radiological, histological, and microbiological examinations, immunohistochemistry, immunofluorescence, and micro-CT scans.

Results: In general, NBD peptides effectively reduced clinical signs in rabbits when compared with the control group. Radiography indicated that there was more severe osteomyelitis in the bacterium-infection control group. There was no significance between cefazolin- and NBD-group average scores. The histological results of the lesion slices further confirmed different severity among the groups. Additionally, significant pathological differences were found between the cefazolin and NBD groups, and the PBS group showed no obvious pathological changes.

Conclusion: Prophylactic administration of NBD peptides to bone-defect areas inhibited bacterial spread and promoted bone regeneration, making NBD peptides a possible treatment option for prophylaxis in bone infections.

Keywords: NBD peptide; Staphylococcus aureus; bone infection; osteomyelitis.