HMOX1 and major depressive disorder: For example, Michels et al. [167] found increased GSH levels by 23% in PTSD cases compared to HC, while later on, Ogłodek reported increased plasma levels of GSH-Rd and HO-1, but reduced PON-1 levels in PTSD patients vs. HC, with the most pronounced aberrations in PTSD individuals with comorbid severe depression [168,169].