Glial cell line-derived neurotrophic factor and is the first member of the GDNF family of ligands (GFL) found. Glial cell line-derived neurotrophic factor has been shown to interact with GFRA2 and GDNF family receptor alpha 1. GDNF has regenerative properties for brain cells and showed potential as treatment for Parkinson's disease - monkeys with an induced form of Parkinson's disease showed less trembling when treated with the drug, and neuronal fibres grew in part of the human brain exposed to the drug. However progress to a treatment is hampered by the problem of delivering the drug to brain cells through the blood-brain barrier in human.
Glial scar of the injury increase gene expression, thus compounding the response of other astrocytes and contributing to the heterogeneity. Particularly, astrocytes closest to the lesion generally secrete more inhibitory molecules into the extracellular matrix. Microglia are the second most prominent cell type present within the glial scar. They are the nervous system analog of immune system macrophages. Microglia rapidly activate near the injury and secrete several cytokines, bioactive lipids, coagulation factors, reactive oxygen intermediates, and neurotrophic factors. The expression of these molecules depends on the location of the microglial cells relative to the injury, with the cells closest to the injury