Brain/metabolism; Demyelinating Diseases/metabolism; Myelin Sheath/metabolism; Nerve Regeneration/genetics; Sialoglycoproteins/metabolism; Up-Regulation/physiology; Animals; Astrocytes/cytology; Astrocytes/drug effects; Astrocytes/metabolism; Brain/pathology; Cell Division/drug effects; Cell Division/genetics; Cells, Cultured; Coculture Techniques; Cuprizone; Demyelinating Diseases/chemically induced; Demyelinating Diseases/genetics; Disease Models, Animal; Female; Gene Expression Regulation, Developmental/drug effects; Gene Expression Regulation, Developmental/genetics; Mice; Mice, Inbred C57BL; Mice, Knockout; Microglia/cytology; Microglia/drug effects; Microglia/metabolism; Myelin Proteins/genetics; Myelin Proteins/metabolism; Myelin Sheath/drug effects; Oligodendroglia/cytology; Oligodendroglia/metabolism; Osteopontin; Rats; Recombinant Fusion Proteins/pharmacology; Sialoglycoproteins/deficiency; Sialoglycoproteins/genetics; Stem Cells/cytology; Stem Cells/metabolism