The promoting effects of sesamin on osteoblast differentiation of human mesenchymal stem cells

Sesamin, a major lignan in sesame seeds and oils, is well known for its health promotion activity. However, its effects on bone cell functions are infrequently observed. In the study, the effects of sesamin on the differentiation of human mesenchymal stem cells (MSCs), osteoblasts, were examined. The differentiation of cells into osteoblasts suggested that sesamin (SE) in combination with osteogenic factors (OS) significantly increased calcium deposition. Although the osteoblastic differentiation markers including bone morphogenetic protein 2 (BMP-2), type I collagen (COL1A1) and alkaline phosphatase (ALP) of each cell donor showed different expressions both in gene type and time point, the increasing trends of COL1A1 and ALP were observed within the condition of OS + SE being compared with OS treatment. Increased ALP activity in OS + SE treatment could mediate the stimulatory effect of sesamin on osteoblast differentiation. Increased phosphorylation of p38 and ERK were related to increasing of ALP activity and mineralization in OS + SE treatment. Hence, it is suggested that sesamin enhanced osteoblast differentiation via activation of those MAPK signalling cascades. All results present that sesamin benefits differentiation of osteoblast progenitors towards functional bone forming cells, osteoblast. Thereby, sesamin would be a potential food supplement promoting bone health.