In embryonic hearts explanted on collagen gels, epicardial cells delaminate and form vascular tubes, thus providing a model for coronary tubulogenesis. Using this model, we show that fibroblast growth factors (FGFs) 1, 2, 4, 8, 9, and 18 contribute to tubulogenesis and that the availability of multiple FGFs provides the optimal tubulogenic response. Moreover, the FGF effects are vascular endothelial growth factor (VEGF) -dependent, while VEGF-induced tubulogenesis requires FGF signaling.
View Article and Find Full Text PDFExogenous bone marrow-derived cells (BMDCs) are promising therapeutic agents for the treatment of tissue ischemia and traumatic injury. However, until we identify the molecular mechanisms that underlie their actions, there can be no rational basis for the design of therapeutic strategies using BMDCs. The pro-healing effects of BMDCs are apparent very shortly after treatment, which suggests that they may exert their effects by the modulation of acute inflammation.
View Article and Find Full Text PDFInt J Physiol Pathophysiol Pharmacol
November 2009
Bone marrow-derived cells contribute to repair of injured tissue and to the maintenance of tissue homeostasis, but the extent to which perturbations of systemic homeostasis modulate this contribution is unknown. Accordingly, hematopoietic chimeras were used to determine contributions of bone marrow-derived cells to hepatocytes, skeletal muscle myocytes, and cardiomyocytes in healthy young, healthy old, and young obese diabetic mice. Mice with multiple genomic copies of a non-expressed β-globin/pBR322 sequence served as bone marrow donors.
View Article and Find Full Text PDFAims/hypothesis: Bone marrow cell mobilisation potently induces vascular growth in ischaemic tissue, possibly by mobilising endothelial cell progenitors. Thus, mobilising agents might not be therapeutic when endothelial cell progenitors are dysfunctional, as in diabetes mellitus. Local injection of autologous endothelial cell progenitors also stimulates vascular growth in ischaemic tissue, but endothelial cell progenitors from people with multiple cardiovascular risk factors and from obese diabetic mice are marginally therapeutic or inhibitory.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
January 2007
Over the past decade, the old idea that the bone marrow contains endothelial cell precursors has become an area of renewed interest. While some still believe that there are no endothelial precursors in the blood, even among those who do, there is no consensus as to what they are or what they do. In this review, we describe the problems in identifying endothelial cells and conclude that expression of endothelial nitric oxide synthase may be the most reliable antigenic indicator of the phenotype.
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