Uncovering the effect of low-frequency static magnetic field on tendon-derived cells: From mechanosensing to tenogenesis

Abstract

Magnetotherapy has been receiving increased attention as an attractive strategy for modulating cell physiology directly at the site of injury, thereby providing the medical community with a safe and non-invasive therapy. Yet, how magnetic field influences tendon cells both at the cellular and molecular levels remains unclear. Thus, the influence of a low-frequency static magnetic field (2 Hz, 350 mT) on human tendon-derived cells was studied using different exposure times (4 and 8 h; short-Term studies) and different regimens of exposure to an 8h-period of magnetic stimulation (continuous, every 24 h or every 48 h; long-Term studies). Herein, 8 h stimulation in short-Term studies significantly upregulated the expression of tendon-Associated genes SCX, COL1A1, TNC and DCN (p < 0.05) and altered intracellular Ca2+ levels (p < 0.05). Additionally, every 24 h regimen of stimulation significantly upregulated COL1A1, COL3A1 and TNC at day 14 in comparison to control (p < 0.05), whereas continuous exposure differentially regulated the release of the immunomodulatory cytokines IL-1β and IL-10 (p < 0.001) but only at day 7 in comparison to controls. Altogether, these results provide new insights on how low-frequency static magnetic field fine-Tune the behaviour of tendon cells according to the magnetic settings used, which we foresee to represent an interesting candidate to guide tendon regeneration.