Adipose tissue in bone regeneration - stem cell source and beyond

Abstract

Adipose tissue (AT) is recognized as a complex organ involved in major home-ostatic body functions, such as food intake, energy balance, immunomodulation, development and growth, and functioning of the reproductive organs. The role of AT in tissue and organ homeostasis, repair and regeneration is increasingly recognized. Different AT compartments (white AT, brown AT and bone marrow AT) and their interrelation with bone metabolism will be presented. AT-derived stem cell populations - adipose-derived mesenchymal stem cells and pluripotent-like stem cells. Multilineage differentiating stress-enduring and dedifferentiated fat cells can be obtained in relatively high quantities compared to other sources. Their role in different strategies of bone and fracture healing tissue engineering and cell therapy will be described. The current use of AT- or AT-derived stem cell populations for fracture healing and bone regenerative strategies will be presented, as well as major challenges in furthering bone regenerative strategies to clinical settings.

Keywords: Adipose tissue; Adipose-derived stem cells; Bone engineering; Bone metabolism; Dedifferentiated fat cells; Fracture healing; Multilineage differentiating stress-enduring.

Figure 1

Adipose-derived mesenchymal stem cell osteogenesis under magnetomechanical stimulation. A: Osteogenesis of adipose-derived mesenchymal stem cells (ADSCs) loaded with micronutrient powders (MNPs) exposed to alternating MFs; B: Osteogenesis of ADSCs without MNPs exposed to MFs assessed with OsteoImage^® Lonza showing green fluorescence for the deposited calcified extracellular matrix.