Acceleration by MS-818 of early muscle regeneration and enhanced muscle recovery after surgical transection

Morphological and functional evaluation of the effect of novel pyrimidine derivatives on regeneration of the sciatic nerve in rats

Two novel pyrimidine derivatives, RG2 and RG6, were studied using a rat's model of peripheral nerve injury. Toe-spreading reflex and skin sensitivity to pinch in the foot were monitored to follow recovery of motor and sensory functions in the treated animals. The remyelation rate in the distal segment of the damaged nerve was also studied using morphological analysis of cross-sections of the nerve stained with methylene blue. The obtained data demonstrate a high stimulating effect of RG2 and RG6 on the restoration of motor and sensory functions of the sciatic nerve, as well as on the post-traumatic regeneration of myelin fibers. Possible mechanisms of the observed effects are discussed.

Stem Cell Therapies for Neurodegenerative Diseases

Stem cell therapies have been proposed as a treatment option for neurodegenerative diseases, but the best stem cell source and therapeutic efficacy for neuroregeneration remain uncertain. Embryonic stem cells (ESCs) and neural stem cells (NSCs), which can efficiently generate neural cells, could be good candidates but they pose ethical and practical issues. Not only difficult to find the good source of those cells but also they alway pose immunorejection problem since they may not be an autologous cells. Even if we overcome the immunorejection problem, it has also been reported that transplantation of ESCs develop teratoma. Although adult stem cells are more accessible, they have a limited developmental potential. We developed technologies to increase potency of mesenchymal stem cells, which allow them to develop into neural cells, by over expression of the ESC gene, nanog. We also developed a small molecule compound, which significantly increases endogenous NSCs by peripheral administration, eliminating even the necessity of stem cell injection to the brain. These novel technologies may offer neuroregenerative therapies for Alzheimers disease (AD). However, we found that AD pathological condition prevent neurogenesis from NSCs. This chapter discusses how to overcome the problem associated stem cell therapy under AD pathology and introduces exosome as a tool to improve the modification of adult stem cells. These new technologies may open a door for the new era for AD therapy.

Engineering skeletal muscle tissue--new perspectives in vitro and in vivo

Muscle tissue engineering (TE) has not yet been clinically applied because of several problems. However, the field of skeletal muscle TE has been developing tremendously and new approaches and techniques have emerged. This review will highlight recent developments in the field of nanotechnology, especially electrospun nanofibre matrices, as well as potential cell sources for muscle TE. Important developments in cardiac muscle TE and clinical studies on Duchenne muscular dystrophy (DMD) will be included to show their implications on skeletal muscle TE.

MS-818 Accelerates Mobilization of Endothelial Progenitor Cells and Differentiation to Endothelial Cells

MS-818 that is a synthetic pyrimidine compound and shown to have neurotrophic actions, enhanced basic fibroblast growth factor (bFGF)-induced angiogenesis in vivo. However, the mechanism and whether MS-818 affects endothelial cells (ECs) directly is not known. Here, the authors investigated whether MS-818 alone could induce angiogenesis and tried to clarify the mechanism of neovascularization by MS-818 in terms of angiogenesis and vasculogenesis. The authors show that MS-818 affects ECs directly and induces migration of and tube formation by ECs in vitro (angiogenesis). Furthermore, the authors demonstrate that MS-818 mobilizes endothelial progenitor cells (EPCs) from the bone marrow and potentiates their differentiation to ECs (vasculogenesis). The effect of MS-818 on the endothelial differentiation was further confirmed with an in vitro differentiation system using mouse embryonic stem cells. MS-818 activates the mitogen-activated protein kinase (MAPK) pathway but not the phosphoinositol 3-kinase (PI3K)-Akt pathway in ECs. These results indicate that MS-818, a synthetic compound, promotes both angiogenesis and vasculogenesis.