4.4. Cell cycle genes

The upregulation of cell cycle genes, including cyclins, c-Myc (V-myc avian myelocytomatosis viral oncogene homolog) and GADD45A (growth arrest and DNA damage-inducible, alpha), is being reported after 24 hours of SCI [27]. Once these genes are activated, it induces apoptosis and astrocytic proliferation through formation of the glial scar [27]. In the initial stages of SCI, upregulation of associated genes, such as BAX (BCL2-associated X protein), BAK-1 (BCL2-antagonist/killer 1) and CASP3 (caspase 3, apoptosis-related cysteine peptidase), is being reported. In later stages, the upregulation of STAT3 (signal transducer and activator of transcription 3 (acute-phase response factor)) and PI3K (phosphoinositide 3-kinase) and downregulation of GSK-3 (glycogen synthase kinase 3) are being observed [25]. In addition, earlier upregulation of genes that are involved in preventing apoptosis such as PDGF (platelet-derived growth factor), TGFB (transforming growth factor-β), VEGF (vascular endothelial growth factor) and anti-apoptotic proteins is being reported [24].
