However, it is important to note that not always there is a concordance between the mRNA and protein expression data [88–90] and that other antioxidant enzymes in the cell could also be relevant as scavenger molecules during the pathological process of NIHL such as Sod1, Catalase and Glutathione peroxidases (GPx1, GPx2 or GPx3). Here, GPX2 is linked to noise induced hearing loss.