However, conversely there are conflicting reports of higher levels of serum 3-hydroxykynurenine in AD [19], higher levels of serum kynurenine and anthranilic acid in females with a high neocortical amyloid-β load [10] and positive correlations between serum kynurenine metabolites with plasma amyloid-β(1–42) and neurofilament light chain [11]. Here, NEFL is linked to Alzheimer disease.