Increased extracellular matrix deposition during chondrogenic differentiation of dental pulp stem cells from individuals with neurofibromatosis type 1: an in vitro 2D and 3D study

Abstract

Neurofibromin converts Ras from an active (Ras-GTP) to an inactive form (Ras-GDP) [2]. [...]mutations in the NF1 gene lead to an increased intracellular Ras-activity [3]. To consider stem cells from dental origin as a potential in vitro model for studying NF1, a better characterization of those cells is mandatory. Activated Ras continually activates numerous intracellular signaling pathways, such as p38 kinase and MAPK/ERK pathway [3]. [...]a possible explanation for the greater deposition of extracellular matrix found in our study after chondrogenic differentiation is the constant activation of Ras, which elevates p38 kinase and ERK levels during the entire process of chondrogenic differentiation. [...]the absence of Ki-67 expression demonstrated that the cells had achieved the terminal stage of differentiation.