Studies have identified significant changes in sphingolipid levels at the onset of AD, with further results showing that increased ceramide levels that may contribute to neuronal death through oxidative stress and decreased sphingomyelin levels, implicating these lipids in the metabolism of APP and suggesting a complex role in AD progression (He et al., 2010; Castro et al., 2009; Söderberg et al., 1992). Here, APP is linked to Alzheimer disease.