Low-frequency electromagnetic fields combined with tissue engineering techniques accelerate intervertebral fusion.

Abstract

BACKGROUND: Intervertebral fusion is the most common surgery to treat lumbar degenerative disease (LDD). And the graft material used in the operation is derived from the iliac crest to promote fusion. However, autografts possess the fatal disadvantage of lack of source. Therefore, economical and practical bone substitutes are urgently needed to be developed. Sinusoidal electromagnetic fields (EMF) combined with tissue engineering techniques may be an appropriate way to promote intervertebral fusion. METHODS: In this research, porous scaffolds made of polycaprolactone (PCL) and nano-hydroxyapatite (nHA) were used as cell carriers. Then, the scaffolds loaded with bone marrow mesenchymal stem cells (BMSCs) were treated with sinusoidal electromagnetic field and the osteogenic capability of BMSCs was tested later. In addition, an intervertebral disc of the tail vertebra of the rat was removed to construct a spinal intervertebral fusion model with a cell-scaffold implanted. The intervertebral fusion was observed and analyzed by X-ray, micro-CT, and histological methods. RESULTS: BMSCs stimulated by EMF possess splendid osteogenic capability under an osteogenic medium (OM) in vitro. And the conditioned medium of BMSCs treated with EMF can further promote osteogenic differentiation of the primitive BMSCs. Mechanistically, EMF regulates BMSCs via BMP/Smad and mitogen-activated protein kinase (MAPK)-associated p38 signaling pathways. In vivo experiments revealed that the scaffold loaded with BMSCs stimulated by EMF accelerated intervertebral fusion successfully. CONCLUSION: In summary, EMF accelerated intervertebral fusion by improving the osteogenic capacity of BMSCs seeded on scaffolds and might boost the paracrine function of BMSCs to promote osteogenic differentiation of the homing BMSCs at the injured site. EMF combined with tissue engineering techniques may become a new clinical treatment for LDD.

AI evidence extraction

Main findings

In vitro, BMSCs stimulated by sinusoidal EMF showed increased osteogenic capability under osteogenic medium, and conditioned medium from EMF-treated BMSCs promoted osteogenic differentiation of untreated BMSCs. Mechanistically, EMF was reported to regulate BMSCs via BMP/Smad and MAPK-associated p38 pathways. In a rat tail vertebra fusion model, scaffolds loaded with EMF-stimulated BMSCs accelerated intervertebral fusion based on imaging and histology.

Outcomes measured

• Osteogenic capability/differentiation of BMSCs in vitro
• Paracrine/conditioned-medium effects on osteogenic differentiation
• BMP/Smad signaling pathway activity
• MAPK-associated p38 signaling pathway activity
• Intervertebral fusion in vivo assessed by X-ray, micro-CT, histology

Limitations

• EMF exposure parameters (e.g., field strength, frequency, duration) not reported in the abstract
• Sample size not reported in the abstract
• Animal model and in vitro findings may not directly translate to humans
• Scaffold composition and cell-loading details are limited to brief description in the abstract

{
    "study_type": "animal",
    "exposure": {
        "band": "ELF",
        "source": "therapeutic/experimental sinusoidal electromagnetic field",
        "frequency_mhz": null,
        "sar_wkg": null,
        "duration": null
    },
    "population": "Rat tail vertebra intervertebral fusion model; bone marrow mesenchymal stem cells (BMSCs) in vitro",
    "sample_size": null,
    "outcomes": [
        "Osteogenic capability/differentiation of BMSCs in vitro",
        "Paracrine/conditioned-medium effects on osteogenic differentiation",
        "BMP/Smad signaling pathway activity",
        "MAPK-associated p38 signaling pathway activity",
        "Intervertebral fusion in vivo assessed by X-ray, micro-CT, histology"
    ],
    "main_findings": "In vitro, BMSCs stimulated by sinusoidal EMF showed increased osteogenic capability under osteogenic medium, and conditioned medium from EMF-treated BMSCs promoted osteogenic differentiation of untreated BMSCs. Mechanistically, EMF was reported to regulate BMSCs via BMP/Smad and MAPK-associated p38 pathways. In a rat tail vertebra fusion model, scaffolds loaded with EMF-stimulated BMSCs accelerated intervertebral fusion based on imaging and histology.",
    "effect_direction": "benefit",
    "limitations": [
        "EMF exposure parameters (e.g., field strength, frequency, duration) not reported in the abstract",
        "Sample size not reported in the abstract",
        "Animal model and in vitro findings may not directly translate to humans",
        "Scaffold composition and cell-loading details are limited to brief description in the abstract"
    ],
    "evidence_strength": "low",
    "confidence": 0.7399999999999999911182158029987476766109466552734375,
    "peer_reviewed_likely": "yes",
    "keywords": [
        "low-frequency electromagnetic fields",
        "sinusoidal electromagnetic field",
        "tissue engineering",
        "polycaprolactone",
        "nano-hydroxyapatite",
        "bone marrow mesenchymal stem cells",
        "osteogenic differentiation",
        "intervertebral fusion",
        "rat model",
        "BMP/Smad",
        "MAPK p38"
    ],
    "suggested_hubs": []
}

Comments

Log in to comment.

No comments yet.