To investigate the mechanism by which bone tunnel mechanical microenvironment optimization enhances tendon-bone healing after anterior cruciate ligament reconstruction,with a focus on the TAK1/NF-κB/MAPK signaling pathway
SHEN Fuguo
XIAO Wenlong
SUN Wencai
JIN Song
CUI Dongmei
Abstract：Objective To explore the facilitative effect of optimizing the mechanical microenvironment of the bone tunnel on tendon-bone healing after anterior cruciate ligament(ACL)reconstruction,and its regulatory correlation with the Transforming growth factor-β-activated kinase 1(TAK1)/Nuclear factor kappa-B(NF-κB)/Mitogen-activated protein kinase(MAPK)signaling pathway.Methods A rabbit model of anterior cruciate ligament(ACL)reconstruction was established and randomly allocated into four groups:the normal control(NC)group,the conventional forward drilling without bone grafting(FD)group,the forward drilling plus bone grafting(FD+BG)group,and the reverse drilling plus bone grafting(RD+BG)group.Hematoxylin-eosin(HE)staining was carried out to observe the histomorphological changes at the tendon-bone interface.Quantitative real-time polymerase chain reaction(qRT-PCR)was utilized to detect the messenger ribonucleic acid(mRNA)expressions of inflamma-tory factors interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α).Enzyme-linked immunosorbent assay(ELISA)was applied to measure the concentrations of the angiogenesis-related factor vascular endothelial growth factor(VEGF)and the tissue repair factor transforming growth factor-β1(TGF-β1).Western blot analysis was performed to evaluate the protein expressions of osteogenic factors osteocalcin(OCN),osteopontin(OPN),and key proteins in the TAK1/NF-κB/MAPK signaling pathway.Results Histomorphological findings indicated that the RD+BG group achieved the most optimal tendon-bone interface fusion,characterized by dense and mature newly-formed bone trabeculae.When compared with the FD+BG group,the RD+BG group showed significantly downregulated mRNA expressions of IL-6 and TNF-α,remarkably upregulated levels of VEGF,TGF-β1,along with protein expressions of OCN and OPN,and notably decreased phosphorylation ratios of key proteins in the TAK1/NF-κB/MAPK pathway(p-TAK1/TAK1,p-p65/p65,p-p38/p38)(P<0.05).Conclusion Optimization of the bone tunnel mechanical microenvironment(RD+BG)can effectively balance local inflammatory responses,precisely upregulate the expressions of repair-related and osteogenic factors,and consequently accelerate tendon-bone healing after ACL reconstruction.This process might be closely associated with the activation changes of the TAK1/NF-κB/MAPK signaling pathway,offering novel experimental evidence for the clinical refinement of ACL reconstruction surgery.
Keywords：anterior cruciate ligament reconstructiontendon-bone healingmechanical microenviron-mentTAK1/NF-κB/MAPK signaling pathwayosteogenic differentiationinflammatory regulation
Publication Date：2026-03-10
Online Publishing Date：2026-03-20(First online date of this platform, not the publication date of the document)
Pages：7( 807-813 )