期刊名称：International Journal of Health, Animal Science and Food Safety
印刷版ISSN：2283-3927
出版年度：2016
卷号：3
期号：1s
语种：English
出版社：Department of Health, Animal Science and Food Safety (VESPA)
摘要：Epigenetic conversion overcomes the stability of a terminally differentiated cell, allowing phenotype switch and providing an unlimited source of autologous cells of a different type. It is based on the exposure to an epigenetic modifier that increases cell plasticity, followed by a differentiation protocol. In our work we treat mammalian dermal fibroblasts with the demethylating agent 5-azacytidine. Cell differentiation is directed toward the endocrine pancreatic lineage, with a sequential combination of key growth factors. The overall duration of the process is 36 days (Pennarossa, 2013; Brevini, 2015; Brevini, 2015). However, this protocol, as well as all differentiation procedures described in the literature, uses high and non-physiological concentrations of glucose. Here we report experiments aimed at investigating whether the use of lower glucose concentrations, that more closely mimic the in vivo physiological environment, can support fibroblast conversion into β-like cells. To do so, cells were cultured as described above, but using lower and more physiological glucose levels, namely 5.5 and 8.5 mM that correspond to normoglycaemia before and after meals (International Diabetes Federation, 2007). Our results show that mammalian cells are not able to differentiate into insulin secreting cells in a low glucose environment. In particular, cells do not aggregate into pancreatic islet structures and display an altered gene expression pattern for several early pancreatic markers, when compared to the standard trend obtained with 17.5 mM of glucose. These results suggest that high glucose levels are essential for the achievement of the endocrine pancreatic differentiation process in mammalian cells and appear to be crucial for functional efficiency and morphological organization.
