↑ ERK 1/2 (+22%, t = 2.293, p = 0.03) and JNK (+56%, t = 2.468, p = 0.02) expression in MDD pts, but not p38-MAPK, compared to HC. p-JNK/total JNK and p-p38/total p38 ↑ in MDD > HC. AD-free and AD-treated showed no significant ↑ in Keap-1 expression compared to HC. 21% ↓ of nuclear expression of Nrf2 in MDD pts. Here, MAPK8 is linked to major depressive disorder.