Persistent mesodermal differentiation capability of bone marrow MSCs isolated from aging patients with low energy traumatic hip fracture and osteoporosis: clinical evidence

Abstract

Abstract Background Low-energy trauma-elicited bone fractures represent a sign of bone fragility and ongoing osteoporosis. The low energy hit, such as a slight fall down from a bed, standing height, or fewer, results in a bone fracture, especially in the hip, which is a life-threatening risk for the older adult and a heavy burden for the social economics. Bone can self-heal and maintain the homeostasis of anabolism and catabolism to preserve a healthy bony structure. Meanwhile, bone marrow-derived stem cells (BMSCs) are critical in osteogenesis, leading to metabolic homeostasis in the healthy bony microenvironment. Notably, patients with low-energy traumatic bone fractures usually suffer a higher level of bony catabolism accompanied by osteoporosis. However, whether the BMSCs derived from the patients who suffered osteoporosis and low-energy traumatic hip fracture preserve a sustained mesodermal differentiation capability, especially in osteogenesis, is yet to be explored in a clinical setting.Methods Therefore, we collected BMSCs from clinical hip fracture patients accompanied by evidenced osteoporosis in the current study. The CD markers identification, cytokines examination, and osteogenic and adipogenic differentiation were evaluated and compared with the BMSCs withdrawn from the healthy young donors. Meanwhile, the BMSCs doubling time, doubling level, and cumulative population doubling level of proliferation test were also examined.Results Data reveals that BMSCs collected from elderly osteoporotic patients expressed more abundant interleukin 6 (IL-6) and vascular endothelial growth factor (VEGF) than the BMSCs collected from young donors. However, the CD markers and osteogenic and adipogenic differentiation capability in these elderly osteoporotic patients and healthy young donors are identical. Notably, the proliferation capability of BMSCs derived from aging osteoporotic patients compared with BMSCs from healthy juvenile donors reveal an equivalent level in passages 3 ~ 4 that is conventionally used for clinical cell transplantation.Conclusion Collectively, our data evidence that BMSCs derived from elderly osteoporotic patients hold the equivalent differentiation capability identical to BMSCs derived from youth, and the unbalanced bony homeostasis and subsequent osteoporosis in the older adult need further detailed exploration.