MEG3 and Parkinson disease: Additionally, the expression of lncRNA MEG3, that is involved in the aggravation of non-motor symptoms, cognitive decline, and PD stage, was downregulated in the plasma of PD patients as compared to healthy controls (Quan et al., 2020), whereas lncRNA NEAT1 was observed to be upregulated in peripheral blood cells of PD patients (Boros et al., 2020).