Participation of TNF‐α in Inhibitory Effects of Adipocytes on Osteoblast Differentiation

Abstract

Mesenchymal stem cells from bone marrow (BM-MSCs) and adipose tissue (AT-MSCs) are attractive tools for cell-based therapies to repair bone tissue. In this study, we investigated the osteogenic and adipogenic potential of BM-MSCs and AT-MSCs as well as the effect of crosstalk between osteoblasts and adipocytes on cell phenotype expression. Rat BM-MSCs and AT-MSCs were cultured either in growth, osteogenic, or adipogenic medium to evaluate osteoblast and adipocyte differentiation. Additionally, osteoblasts and adipocytes were indirectly co-cultured to investigate the effect of adipocytes on osteoblast differentiation and vice versa. BM-MSCs and AT-MSCs exhibit osteogenic and adipogenic potential under non-differentiation-inducing conditions. When exposed to osteogenic medium, BM-MSCs exhibited higher expression of bone markers compared with AT-MSCs. Conversely, under adipogenic conditions, AT-MSCs displayed higher expression of adipose tissue markers compared with BM-MSCs. The presence of adipocytes as indirect co-culture repressed the expression of the osteoblast phenotype, whereas osteoblasts did not exert remarkable effect on adipocytes. The inhibitory effect of adipocytes on osteoblasts was due to the release of tumor necrosis factor alpha (TNF-α) in culture medium by adipocytes. Indeed, the addition of exogenous TNF-α in culture medium repressed the differentiation of BM-MSCs into osteoblasts mimicking the indirect co-culture effect. In conclusion, our study showed that BM-MSCs are more osteogenic while AT-MSCs are more adipogenic. Additionally, we demonstrated the key role of TNF-α secreted by adipocytes on the inhibition of osteoblast differentiation. Thus, we postulate that the higher osteogenic potential of BM-MSCs makes them the first choice for inducing bone repair in cell-based therapies.

Effect of stem cells combined with a polymer/ceramic membrane on osteoporotic bone repair

“…11 For bone regeneration based on the use of cells, several tissues have been investigated as cell source; however, the bone marrow still remains the most common source, at least in part, due to its ease of accessibility and multilineage differentiation potential. 34 In fact, we had previously demonstrated the ability of these cells to differentiate into multilineages, 35 which was associated with the expression of cell surface markers described in the present study, thus allowing to qualify them as MSCs. In this study, we opted for using these bone marrowderived MSCs harvested from healthy animals based on previous reports where these cells either undifferentiated or differentiated into osteoblasts displayed similar potential to induce bone formation, combined with the fact that bone marrow-derived cells induced more bone formation than adiposederived cells.…”

Hyperbaric Oxygen Therapy Improves the Osteogenic and Vasculogenic Properties of Mesenchymal Stem Cells in the Presence of Inflammation In Vitro

“…Despite several other works investigating the influence of TNF-α on osteogenic differentiation of MSCs, its role still remains controversial. Indeed, both stimulatory and inhibitory effects on MSCs osteoblastogenesis have been described for the pro-inflammatory cytokine [54,[56][57][58][59]. Most of these studies, however, agree on the fact that TNF-α influences the MSCs osteogenic differentiation in relation to cytokine concentration, timing and duration of administration, as well as to the cell types and species used [60][61][62][63].…”

Clinical applications of the jugal lipectomy technique: case reports

“…Recently, the literature discusses the ability of ABC to be an important source of mesenchymal stem cells, promising to produce bone tissue, muscle, cartilage, and fat. However, such information is not yet accurate and further studies are needed [12,13] .…”