Differential involvement of phosphatidylinositol 3-kinase and p42/p44 mitogen activated protein kinase pathways in brain-derived neurotrophic factor-induced trophic effects on cultured striatal neurons.
Brain-derived neurotrophic factor (BDNF) is a potent trophic factor for striatal cells that promotes survival and/or differentiation of GABAergic neurons in vitro. In the present study, we show that the stimulation of cultured striatal cells with BDNF increased the phosphorylation of Akt and p42/p44. This effect was specifically blocked by inhibitors of phosphatidylinositol 3-kinase (PI3-K) pathways (LY294002 and wortmannin) or p42/p44 mitogen-activated protein (MAP) kinase (PD98059 and U0126). BDNF treatment induced an increase in the number of calbindin-positive neurons but not in the number of GABAergic or total cells. Furthermore, BDNF increased the degree of dendritic arborization, soma area and axon length of striatal neurons. However, PD98059 was more effective blocking BDNF effects on calbindin- than on GABA-positive neurons, whereas LY294002 inhibited morphological differentiation in both neuronal populations. Moreover, BDNF induced neuronal survival only through the activation of the PI3-K pathway.
Gavaldà
Núria
N
Departament de Biologia Cel.lular i Anatomia Patològica, Facultat de Medicina, Universitat de Barcelona, IDIBAPS, 08036 Barcelona, Spain.
Pérez-Navarro
Esther
E
Gratacòs
Elena
E
Comella
Joan X
JX
Alberch
Jordi
J
D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology*; D002478:Cells, Cultured; D003342:Corpus Striatum / Q000187:drug effects* / Q000201:enzymology; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D005260:Female; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009474:Neurons / Q000187:drug effects / Q000201:enzymology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley
D019208:Brain-Derived Neurotrophic Factor; D019869:Phosphatidylinositol 3-Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases