Bone Marrow Mesenchymal Stromal Cells Stimulate Skeletal Myoblast Proliferation through the Paracrine Release of VEGF

Abstract

Mesenchymal stromal cells (MSCs) are the leading cell candidates in the field of regenerative medicine. These cells have also been successfully used to improve skeletal muscle repair/regeneration; however, the mechanisms responsible for their beneficial effects remain to be clarified. On this basis, in the present study, we evaluated in a co-culture system, the ability of bone-marrow MSCs to influence C2C12 myoblast behavior and analyzed the cross-talk between the two cell types at the cellular and molecular level. We found that myoblast proliferation was greatly enhanced in the co-culture as judged by time lapse videomicroscopy, cyclin A expression and EdU incorporation. Moreover, myoblasts immunomagnetically separated from MSCs after co-culture expressed higher mRNA and protein levels of Notch-1, a key determinant of myoblast activation and proliferation, as compared with the single culture. Notch-1 intracellular domain and nuclear localization of Hes-1, a Notch-1 target gene, were also increased in the co-culture. Interestingly, the myoblastic response was mainly dependent on the paracrine release of vascular endothelial growth factor (VEGF) by MSCs. Indeed, the addition of MSC-derived conditioned medium (CM) to C2C12 cells yielded similar results as those observed in the co-culture and increased the phosphorylation and expression levels of VEGFR. The treatment with the selective pharmacological VEGFR inhibitor, KRN633, resulted in a marked attenuation of the receptor activation and concomitantly inhibited the effects of MSC-CM on C2C12 cell growth and Notch-1 signaling. In conclusion, this study provides novel evidence for a role of MSCs in stimulating myoblast cell proliferation and suggests that the functional interaction between the two cell types may be exploited for the development of new and more efficient cell-based skeletal muscle repair strategies.

Extracellular Vesicles Secreted by Human Urine-Derived Stem Cells Promote Ischemia Repair in a Mouse Model of Hind-Limb Ischemia

“…In this study, we observed that both USCs-EVs and iMSCs-EVs promoted C2C12 myoblast proliferation. Previous studies reported that VEGF, HGF and IGF-1 were not only potential proangiogenic factors but also promoted myoblast proliferation [53][54][55][56][57][58][59]. In the present study, we found that VEGF, HGF and IGF-1 were loaded in the USCs-EVs.…”

Prevention of Bleomycin-Induced Lung Inflammation and Fibrosis in Mice by Naproxen and JNJ7777120 Treatment

“…Tissue samples were homogenized on ice and lysed as previously reported (Sassoli et al, 2012). Total protein extract (1 mg) was precleared by Protein G (Sigma-Aldrich) for 1 hour at 4°C.…”

Intravenous administration of bone marrow-derived multipotent mesenchymal stromal cells enhances the recruitment of CD11b+ myeloid cells to the lungs and facilitates B16-F10 melanoma colonization

“…One of them is through support to the growth of endogenous progenitor cells such as cardiac stem cells [29] and skeletal myoblasts [30]. The mitogenic stimuli provided by MSCs are mediated by secreted molecules such as the vascular endothelial growth factor (VEGF), or by direct cell-to-cell contact interactions [31].…”