BECN1 and Parkinson disease: Transplantation of bone marrow mesenchymal stem cells upregulated beclin-1 expression, increasing autophagy in the hippocampus to clear Aβ.300 Furthermore, changes in bone-derived cytokines during ageing may also be implicated in several neurodegenerative diseases.301 For example, OCN decreases the Aβ load, increases glycolysis in microglia and astrocytes,302 and ameliorates motor deficits and dopaminergic neuronal loss in PD mice.303 LCN2 and sclerostin aggravate neuroinflammation and abolish synaptic plasticity,304,305 thereby accelerating the progression of AD, PD and ALS.306–308