Nerve Growth Factor-Induced Differentiation of PC12 Cells Is Accompanied by Elevated Adenylyl Cyclase Activity

Abstract

Rat pheochromocytoma (PC12) cells characteristically undergo differentiation when cultured with nerve growth factor (NGF). Here we show that NGF dramatically increased the adenylyl cyclase-activating property of forskolin in PC12 cells. This effect of NGF was well maintained even when NGF was removed after 4 days, even though the morphological features of neuronal differentiation were rapidly lost on removal of NGF. The enhanced cAMP production in response to forskolin could be due to a synergistic interaction between forskolin and endogenously released agonists acting on G_s-coupled receptors. However, responses to forskolin were not attenuated by antagonists of adenosine A2 receptors or pituitary adenylate cyclase-activating polypeptide (PACAP) receptors, suggesting that adenosine and PACAP were not involved. Adenylyl cyclases 3, 6 and 9 were the predominant isoforms expressed in PC12 cells, but we found no evidence for NGF-induced changes in expression levels of any of the 9 adenylyl cyclase isoforms, nor in the expression of Gα_s. These findings highlight that NGF has a subtle influence on adenylyl cyclase activity in PC12 cells which may influence more than the neurite extension process classically associated with neuronal differentiation.

Control of neurite outgrowth by RhoA inactivation

“…2006; Chen et al. 2010; Yung et al. 2010), it can be postulated that cAMP produced in the NGF‐signaling pathway is involved in triggering the initiation of neurite outgrowth.…”

“…It is likely that d-catenin is also related to the determination of neurite number of PC12 cells in response to cAMP. Because the cAMP which is produced by NGF in PC12 cells is a mediator of the differentiation of PC12 cells (Stessin et al 2006;Chen et al 2010;Yung et al 2010), it can be postulated that cAMP produced in the NGFsignaling pathway is involved in triggering the initiation of neurite outgrowth. However, it is not clear whether RhoA activity controls the number of primary processes.…”

P-Rex1 Controls Sphingosine 1-Phosphate Receptor Signalling, Morphology, and Cell-Cycle Progression in Neuronal Cells

“…We tested whether the increased cAMP levels derived from elevated expression levels of adenylyl cyclase in P-Rex1-deficient PC12-S1PR1 cells. Mammals have 10 different isoforms of adenylyl cyclases, and the major isoforms expressed in neuronal PC12 cells are adenylyl cyclases 3, 6, and 9 [ 54 ]. Against our expectations, Western blotting of total cell lysates showed that P-Rex1 deficiency decreased the level of adenylyl cyclase isoforms AC3 and AC9 compared to wild-type cells, and it also had a tendency to decrease the level of AC6 ( Figure 4 E,F).…”

Mesenchymal Stromal Cells to Treat Brain Injury

“…Further, the exact timing and concentration of the trophic factor are likely critical in determining to which pathways they contribute. Restore BBB (Nag et al, 2011) ANG-2 neuronal (Bechara et al, 2007) HB-EGF (Opanashuk et al, 1999) (Jin et al, 2002) neuronal (Jin et al, 2004) and glial (Korblum 1999) HGF (Honda et al, 1995;Shang et al, 2011) (Shang et al, 2011 neuronal and glial (Shang et al, 2011) (Hamanoue et al, 1996Shang et al, 2011;Shimamura et al, 2006) (* Distler et al, 2003;Shang et al, 2011;Shimamura et al, 2006) ↑ MSC homing (Neuss et al, 2004;Ponte et al, 2007;Son et al, 2006); ↓ glial scar (Shang et al, 2011;Shimamura et al, 2006) ↑cell homing (Sugiura et al, 2000) MCP-1 (Widera et al, 2004;Yan et al, 2007) ↑MSC homing M-CSF (Vincent et al, 2002) (Minamino et al, 2005) NGF (* Lykissas et al, 2007;Shirakura et al, 2004) neuronal (Yung et al, 2010;Zhu et al, 2011) Lee et al, 2011) *Indicates review article; NSC=Neural stem/progenitor cell; Growth factor abbr...…”