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arXiv · 2003.05893

The effect of pulsed electromagnetic field exposure on osteoinduction of human mesenchymal stem cells cultured on nano-$TiO_{2}$ surfaces

Nora Bloise·Loredana Petecchia·Gabriele Ceccarelli·Lorenzo Fassina·Cesare Usai·Federico Bertoglio·Martina Balli·Massimo Vassalli·Maria Gabriella Cusella De Angelis·Paola Gavazzo·Marcello Imbriani·Livia Visai
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Abstract

Human bone marrow-derived mesenchymal stem cells (hBM-MSCs) are considered a great promise in the repair and regeneration of bone. Considerable efforts have been oriented towards uncovering the best strategy to promote stem cells osteogenic differentiation. In previous studies, hBM-MSCs exposed to physical stimuli such as pulsed electromagnetic fields (PEMFs) or directly seeded on nanostructured titanium surfaces ($TiO_{2}$) were shown to improve their differentiation to osteoblasts in osteogenic condition. In the present study, the effect of a daily PEMF-exposure on osteogenic differentiation of hBM-MSCs seeded onto nanostructured $TiO_{2}$ (with clusters under 100 nm of dimension) was investigated. $TiO_{2}$-seeded cells were exposed to PEMF (magnetic field intensity: 2 mT; intensity of induced electric field: 5 mV; frequency: 75 Hz) and examined in terms of cell physiology modifications and osteogenic differentiation. Results showed that PEMF exposure affected $TiO_{2}$-seeded cells osteogenesis by interfering with selective calcium-related osteogenic pathways, and greatly enhanced hBM-MSCs osteogenic features such as the expression of early/late osteogenic genes and protein production (e.g., ALP, COL-I, osteocalcin and osteopontin) and ALP activity. Finally, PEMF-treated cells resulted to secrete into conditioned media higher amounts of BMP-2, DCN and COL-I than untreated cell cultures. These findings confirm once more the osteoinductive potential of PEMF, suggesting that its combination with $TiO_{2}$ nanostructured surface might be a great option in bone tissue engineering applications.

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Nora Bloise, Loredana Petecchia, Gabriele Ceccarelli, Lorenzo Fassina, Cesare Usai, Federico Bertoglio, Martina Balli, Massimo Vassalli, Maria Gabriella Cusella De Angelis, Paola Gavazzo, Marcello Imbriani, Livia Visai. 2020-03-10. The effect of pulsed electromagnetic field exposure on osteoinduction of human mesenchymal stem cells cultured on nano-$TiO_{2}$ surfaces. https://doi.org/10.1371/journal.pone.0199046

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