Induction of neurite outgrowth by α-phenyl-N-tert-butylnitrone through nitric oxide release and Ras-ERK pathway in PC12 cells

Abstract

It has previously been suggested that the spin trap agent α-phenyl-N-tert-butylnitrone (PBN) induces neurite outgrowth through activation of the Ras-ERK pathway in PC12 cells. However, the chemical properties of PBN contributing to its biological function and the detailed mechanism for the activation of Ras by PBN remain unknown. This study demonstrates that the hydrophobic structure of PBN is related to the activation of Ras, by comparing with hydrophilic analogues of PBN. [¹⁴C]-labelled PBN was found to localize in the lipid fraction and activate Ras indirectly. On the other hand, neurite outgrowth by PBN was inhibited by a nitric oxide (NO) scavenger. Moreover, the neurite outgrowth induced by PBN and the NO donor NOR4 was inhibited by the dominant negative Ras or MAPK/ERK inhibitor. Taken together, these results suggest that PBN is incorporated into the plasma membrane and induces neurite outgrowth in PC12 cells by activating the Ras-ERK pathway through NO release.

Keywords::

• Antioxidant
• neurogenesis
• nitric oxide

Declaration of interest: This work was supported, in part, by Grants-in-Aid for Basic Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology, Japan (No. 17380178, No. 18658118 and No. 19380172 [O.I.]), and by the JSPS Research Fellowship for Young Scientists [H.Y.]. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This paper was first published online on Early Online on 24 March 2010.