Effects of regenerative radioelectric asymmetric conveyer treatment on human normal and osteoarthritic chondrocytes exposed to IL-1β. A biochemical and morphological study

Giulia Collodel,¹ Antonella Fioravanti,² Nicola Antonio Pascarelli,² Antonello Lamboglia,² Vania Fontani,³ Margherita Maioli,^3–5 Sara Santaniello,^4,5 Gianfranco Pigliaru,^4,5 Alessandro Castagna,³ Elena Moretti,¹ Francesca Iacoponi,¹ Salvatore Rinaldi,³ Carlo Ventura<sup>3,5,6

1</sup>Department of Biomedical Sciences (Applied Biology), ²Department of Clinical Medicine and Immunological Sciences (Rheumatology Unit), University of Siena, Siena, Italy; ³Department of Regenerative Medicine, Rinaldi Fontani Institute, Florence, Italy; ⁴Department of Biomedical Sciences, University of Sassari, Sassari, Italy; ⁵Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, Bologna, Italy; ⁶Cardiovascular Department, S Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy

Purpose: Osteoarthritis (OA) is a degenerative disease characterized by a progressive loss of articular cartilage extracellular matrix and is due to functional impairments occurring in chondrocytes. In previous works, we highlighted that Regenerative Tissue Optimization (TO-RGN) treatment with radioelectric asymmetric conveyer (REAC) technology influenced the gene expression profiles controlling stem cell differentiation and the pluripotency of human skin-derived fibroblasts in vitro. Since interleukin-1 beta signaling has been implicated in the induction and progression of this disease (through metalloproteinase-3 synthesis and nitric oxide production), we investigated whether REAC TO-RGN might influence the biochemical and morphological changes induced by interleukin-1 beta in normal and OA chondrocytes.
Methods: The induction of metalloproteinase-3 and proteoglycan synthesis was evaluated by a solid-phase enzyme-amplified sensitivity immunoassay, and nitric oxide production was evaluated with the Griess method. Ultrastructural features were observed by transmission electron microscopy.
Results: REAC TO-RGN treatment decreased nitric oxide and metalloproteinase-3 production in normal and OA chondrocytes, while inducing an increase in proteoglycan synthesis. OA chondrocytes were more affected by REAC TO-RGN treatment than were normal chondrocytes. Ultrastructural changes confirmed that REAC TO-RGN may counteract the negative effects of interleukin-1 beta incubation.
Conclusion: The results of this in vitro study suggest that REAC TO-RGN treatment may represent a new, promising approach for the management of OA.

Keywords: human chondrocytes ultrastructure, metalloproteinase, nitric oxide, proteoglycans, REAC TO-RGN treatment