Distinctive Genetic Activity Pattern of the Human Dental Pulp between Deciduous and Permanent Teeth
PLOS ONE
Authors: Kim, Ji-Hee; Jeon, Mijeong; Song, Je-Seon; Lee, Jae-Ho; Choi, Byung-Jai; Jung, Han-Sung; Moon, Seok Jun; DenBesten, Pamela K.; Kim, Seong-Oh
Abstract
Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11-14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR). Other teeth were used for immunohistochemical analysis (IHC). Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1), leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), and gamma-aminobutyric acid A receptor beta 1 (GABRB1) were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration.
FGF2-responsive genes in human dental pulp cells assessed using a rat spinal cord injury model
JOURNAL OF BONE AND MINERAL METABOLISM
Authors: Sugiyama, Ken; Nagashima, Kosuke; Miwa, Takahiro; Shimizu, Yuta; Kawaguchi, Tomoko; Iida, Kazuki; Tamaoki, Naritaka; Hatakeyama, Daijiro; Aoki, Hitomi; Abe, Chikara; Morita, Hironobu; Kunisada, Takahiro; Shibata, Toshiyuki; Fukumitsu, Hidefumi; Tezuka, Ken-ichi
Abstract
The central nervous system in adult mammals does not heal spontaneously after spinal cord injury (SCI). However, SCI treatment has been improved recently following the development of cell transplantation therapy. We recently reported that fibroblast growth factor (FGF) 2-pretreated human dental pulp cells (hDPCs) can improve recovery in a rat model of SCI. This study aimed to investigate mechanisms underlying the curative effect of SCI enhanced via FGF2 pretreatment; we selected three hDPC lines upon screening for the presence of mesenchymal stem cell markers and of their functionality in a rat model of SCI, as assessed using the Basso, Beattie, and Bresnahan score of locomotor functional scale, electrophysiological tests, and morphological analyses. We identified FGF2-responsive genes via gene expression analyses in these lines. FGF2 treatment upregulated GABRB1, MMP1, and DRD2, which suggested to contribute to SCI or central the nervous system. In an expanded screening of additional lines, GABRB1 displayed rather unique and interesting behavior; two lines with the lowest sensitivity of GABRB1 to FGF2 treatment displayed an extremely minor effect in the SCI model. These findings provide insights into the role of FGF2-responsive genes, especially GABRB1, in recovery from SCI, using hDPCs treated with FGF2.