The Osteogenic Priming of Mesenchymal Stem Cells is Impaired in Experimental Diabetes

Diabetes mellitus encompasses a group of metabolic conditions embracing the dysfunction and failure of various tissues and organs, including bone. Sustained bone alterations seem to result from anabolic, rather than catabolic processes, and suggest a decreased osteoblastic recruitment and activity. Current knowledge on the cellular and molecular mechanisms were provided by studies performed with osteogenic populations cultured in diabetic-simulated conditions, and osteogenic-induced precursor populations harvested from diabetic animals, sustaining an impaired cellular behavior in terms of osteogenic responsiveness and function. However, the reasons leaning to this impairment remain essentially unknown, as the priming capability and functionality of undifferentiated precursors, developed within the diabetic environment, have not been addressed. Accordingly, this work aims to evaluate the functionality and osteogenic priming capability of bone marrow-derived mesenchymal stem cells (MSCs), harvested from animals with experimental diabetes, and grown in the absence of any given differentiation factor. MSCs developed within a diabetic microenvironment displayed an impaired behavior, with diminished cell viability and proliferation, altered cytoskeleton organization, impaired osteogenic priming, and increased adipogenic activation. Further, the osteogenic induction of diabetic MSCs resulted in an impaired osteogenic commitment. The modified cell phenotype may be related, at least in part, with altered activity of ERK WNT and p38 signaling pathways in diabetic-derived cultures. Specific strategies, aiming the modulation of the verified hindrances, may be of therapeutic value to enhance the functionality of diabetic MSCs and sustain an improved outcome in the metabolism and regeneration of the bone tissue in diabetic conditions.