Glial-derived neurotrophic factor GDNF

Especially, in vitro studies helped to understand the different ways of induction by astrocytes. These are able to secrete a range of chemical agents including transforming growth factor-P (TGF-P), glial-derived neurotrophic factor (GDNF), basic... 

Trophic factors exemplified by NGF and its family members, ciliary neurotrophic factor (CNTF) and glial derived neurotrophic factor (GDNF) all utilize increased tyrosine phosphorylation of cellular substrates to mediate neuronal cell survival. Actions of the NGF family of neurotrophins are not only dictated by ras activation through the Trk family of receptor tyrosine kinases, but also a survival pathway defined by phosphatidylinositol-3-kinase activity (Yao and Cooper, 1995), which gives rise to phosphoinositide intermediates that activate the serine/ threonine kinase Akt/PKB (Dudek et al., 1997). Induction of the serine-threonine kinase activity is critical for cell survival, as well as cell proliferation. Hence, for many trophic factors, multiple proteins constitute a functional multisubunit receptor complex that activates rai-depen-dent and ras-independent intracellular signaling. 

Role/Function of NGF. NGF is a neurotrophic protein molecule essential for the growth and survival of sympathetic and small-diameter afferent neurons (nociceptors) [27, 28] and is involved in neuronal function and plasticity [24]. NGF belongs to the neurotrophin family, which also includes the brain-derived neurotrophic factor (BDNF), glial-derived neurotrophic factor (GDNF), neurotrophin-3 (NT-3), and neurotrophin 4/5 (NT-4/5) [29, 30]. 

Villegas, S. N., Njaine, B., Linden, R., and Carri, N. G. (2006). Glial-derived neurotrophic factor (GDNF) prevents ethanol (EtOH) induced B92 glial cell death by both PI3K/AKT and MEK/ERK signaling pathways. Brain Res. Bull. 71(1-3), 116-126. 

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