Proinsulin C-peptide modulates the expression of ERK1/2, type I collagen and RANKL in human osteoblast-like cells (Saos-2)

Publication date: 15 February 2017
Source:Molecular and Cellular Endocrinology, Volume 442
Author(s): Cristina Russo, Veronica Lazzaro, Carmine Gazzaruso, Samantha Maurotti, Yvelise Ferro, Piero Pingitore, Francesca Fumo, Adriana Coppola, Pietro Gallotti, Valentina Zambianchi, Mariangela Fodaro, Emanuela Galliera, Monica Gioia Marazzi, Massimiliano Marco Corsi Romanelli, Sandro Giannini, Stefano Romeo, Arturo Pujia, Tiziana Montalcini
A lower bone mass accompanied by a higher bone fragility with increased risk of fracture are observed in individuals with type 1 diabetes mellitus. Low C-peptide levels are associated with low lumbar mineral density in postmenopausal woman. In this work, we investigated the role of C-peptide on the osteoblast cell biology in vitro. We examined intracellular pathways and we found that C peptide activates ERK1/2 in human osteoblast-like cells (Saos-2). We also observed that proinsulin C-peptide prevents a reduction of type I collagen expression and decreases, in combination with insulin, receptor activator of nuclear factor-κB (RANKL) levels. In this work we show for the first time that Cpeptide activates a specific intracellular pathway in osteoblasts and it modulates the expression of protein involved in bone remodeling. Our results suggest that both C-peptide may have a role in bone metabolism. Further studies are needing to fully clarify its role.



http://ift.tt/2i5XMjy