Effect of Absogen® on aging gene expression in mesenchymal dental pulp stem cells
The dental pulp forms the core of every vital tooth. It has a nutritive,
formative, and reparative function. To fulfill these functions, it has a complex architecture and contains numerous cells and tissues such as lymphatics, neural fibers, connective tissue, blood vessels, and stem cells. Stem cells are pluripotent cells capable of giving rise to specialized cells in the body. The ones present in the dental pulp, also known as dental pulp stem cells (DPSC), are a kind of mesenchymal stem cell (MSC). They were described as well as characterized for the first time by Gronthos et al. in 2000 and were found comparable to bone marrow stem cells (Gronthos et al., 2000). DPSCs express stem cell markers such as Klf4, Oct4, Sox2, SSEA-3, SSEA-4, and Nanog (Ahmed et al., 2016; Kerkis et al., 2007). They respond by differentiating into specialized cells if the dental pulp suffers an insult. They give rise to dentin-forming cells, i.e. odontoblasts when they are damaged due to an external stimulus to help maintain the integrity of the pulp. DPSCs also have adipogenic, osteogenic, chondrogenic, myogenic, and neurogenic potential. The p21 and p16 gene expression is the marker of aging and senescence in the cells which with p53 regulates the aging, senescence, and death in cells. In this pilot study we have analyzed the effect of Absogen on p21 and p16 gene expression in DPSCs where the aging was introduced using D-galactose.
The treatment of D-galactose induced the higher gene expression of aging related genes p21 and p16. This elevated gene expression was decreased with the treatment of Absogen. The initial data of this pilot study suggests that Absogen clearly affects the gene expression of aging genes and it should be tested further of signaling pathways related to the process of aging in various cells like keratinocytes, melanocytes, and other dermal cells.