Bone Marrow Versus Dental Pulp Stem Cells in Osteogenesis

Abstract

Although the consideration of stem cells is currently approaching its hundredth year as one of the organizing principles of developmental biology, it demonstrates no sign of losing its youthful luster. A range of sources of stem cells have been identified that has the potential to self-renewal and capacity to form multiple lineages. Regardless of the discovery of existence of stem cells in various tissues and body fluids, bone marrow has been potentially considered as a persuasive and primeval source of stem cells for treating a wide horizon of disease [1, 2]. Although bone marrow-derived MSCs could be differentiated into mesodermal and non-mesodermal lineages [3–5], osteoblasts, responsible for osteogenesis, and hematopoietic cells, for hematopoiesis are closely associated with the bone marrow, suggesting a reciprocal relationship between the two [6]. Much of the work in MSCs found within the bone marrow stroma on its in vitro and in vivo applications involved in osteogenesis, adipogenesis, cartilage, and muscle formation including osteoblast, osteocytes, adipocytes, chondrocytes, myoblast, and myocytes are gaining importance due to its inherent bone formation capacity [7]. Hence, bone marrow resident stem cells made them the most primitive and promising source from ancient days for treating bone-related diseases. Nevertheless, it is unfortunate that these sources could have not been effective in treatment of all possible diseases due to various disadvantages of BM-MSCs; one of the main drawbacks is that osteogenic potential of bone marrow cells decreases with age [8], and hence, the search for alternate sources of adult stem cells is also underway. It has been demonstrated that stromal adipocytes in bone marrow cavity increases as age increases. In other words, adipocyte accumulation in the human bone marrow stroma correlates with trabecular bone loss with aging [9–12]. Thus, adipose stromal cells both isolated either from bone marrow or from adipose tissue itself has evolved as a contemporary source for bone regeneration [13, 14]. However, we predict that identifying a source that will be similar to the characteristics of bone marrow, possessing inherent bone-forming capacity might be more valuable in bone tissue engineering, repair, and regeneration.