The Expression Profile of Dental Pulp-Derived Stromal Cells Supports Their Limited Capacity to Differentiate into Adipogenic Cells.

Letícia Fracaro,Carmen L K Rebelatto,Roberto H Herai,Paul J Travers,Paulo R S Brofman,Amanda Leitolis,Alejandro Correa,Lidiane M Boldrini-Leite,Alexandra C Senegaglia

doi:10.3390/ijms21082753

Abstract

Mesenchymal stromal cells (MSCs) can self-renew, differentiate into specialised cells and have different embryonic origins—ectodermal for dental pulp-derived MSCs (DPSCs) and mesodermal for adipose tissue-derived MSCs (ADSCs). Data on DPSCs adipogenic differentiation potential and timing vary, and the lack of molecular and genetic information prompted us to gain a better understanding of DPSCs adipogenic differentiation potential and gene expression profile. While DPSCs differentiated readily along osteogenic and chondrogenic pathways, after 21 days in two different types of adipogenic induction media, DPSCs cultures did not contain lipid vacuoles and had low expression levels of the adipogenic genes proliferator-activated receptor gamma (PPARG), lipoprotein lipase (LPL) and CCAAT/enhancer-binding protein alpha (CEBPA). To better understand this limitation in adipogenesis, transcriptome analysis in undifferentiated DPSCs was carried out, with the ADSC transcriptome used as a positive control. In total, 14,871 transcripts were common to DPSCs and ADSCs, some were unique (DPSCs: 471, ADSCs: 1032), and 510 were differentially expressed genes. Detailed analyses of overrepresented transcripts showed that DPSCs express genes that inhibit adipogenic differentiation, revealing the possible mechanism for their limited adipogenesis.

Highlights

Mesenchymal stromal cells (MSCs) are multipotent adult cells and are functionally defined as having the following features: capacity for self-renewal, the ability to differentiate into adipogenic, osteogenic and chondrogenic cell lines [1] and extensive paracrine and immunomodulatory activities [2]
Our results suggest that DPSCs poorly meet the defined criteria for bona fide multipotent MSCs, DPSCs are an interesting cell type with a putative neural potential worth further study
Inconsistent evidence about the adipogenic capacity of DPSCs demands a more thorough molecular characterisation of these cells for comparison with MSCs, such as adipose tissue-derived stromal cells (ADSCs), which are undoubtedly able to differentiate into adipocytes

Summary

Introduction

Mesenchymal stromal cells (MSCs) are multipotent adult cells and are functionally defined as having the following features: capacity for self-renewal, the ability to differentiate into adipogenic, osteogenic and chondrogenic cell lines [1] and extensive paracrine and immunomodulatory activities [2]. Depending on the source, MSCs may have different embryonic origins; for example, adipose tissue-derived stromal cells (ADSCs) have a mesodermal origin, and dental pulp-derived stromal cells (DPSCs) may have an ectodermal origin [4]. Published data are conflicting about the potential and the time required for DPSCs to achieve in vitro adipogenic differentiation. These studies neither clearly showed the presence of cells with lipid vacuoles after differentiation nor provided cell differentiation efficiency/quantification, and their conclusions were based solely on microscopic identification of a few differentiated cells [6,7,8]

Methods

Results

Conclusion