The composition and concentration of these products is influenced by numerous factors, such as neuronal activity, circadian rhythm, biological sex and age.34–36 Among these, proteins such as Aβ, tau, α-synuclein, and huntingtin have gained particular attention because of their association with neurodegenerative conditions such as AD, Parkinson’s (PD) and Huntington’s disease (HD), respectively. This evidence concerns the gene MAPT and Parkinson disease.