Gamma-oryzanol promotes neurite extension in NGF-primed PC12 cells and enhances viability/process elongation in immortalized Schwann cells.

Phytochemicals are natural compounds found in vegetables and fruits. Gamma-oryzanol (Orz) is present in rice bran generated during the milling process. Health effects of Orz have yet to be fully elucidated. We found that Orz treatment enhanced neurite/process extension in both nerve growth factor-primed PC12 pheochromocytoma cells and immortalized Schwann cells (IFRS1 cells). Orz also improved the viability of IFRS1 cells cultured under low-serum conditions. LY294002, a PI3K inhibitor, caused a polygonal cobblestone-like morphology in IFRS1 cells, while Orz treatment cancelled this effect. Although LY294002 increased the number of apoptotic IFRS1 cells, this effect was not influenced by Orz treatment, suggesting that the effects of Orz on Schwann cell morphology are mediated through downstream effectors of the PI3K pathway rather than through cell viability. Taken together, Orz promotes process extension of two types of neural cells and enhances Schwann cell viability, suggesting therapeutic potential for regeneration after peripheral nerve injury.