Novel Nrf2/ARE activator, trans-coniferylaldehyde, induces a HO-1-mediated defense mechanism through a dual p38alpha/MAPKAPK-2 and PK-N3 signaling pathway ; Novel Nrf2/ARE activator, trans-coniferylaldehyde, induces a HO-1-mediated defense mechanism through a dual p38α/MAPKAPK-2 and PK-N3 signaling pathway