Figure 1.

The process of autophagic flux and the putative steps of autophagic dysfunction in human diseases. A normal autophagic flux includes the autophagosome formation and maturation step, the autolysosome formation step and the degradation step. The possible defects that could lead to autophagic dysfunction in different human diseases are depicted: (1) autophagy induction and autophagosome formation; (2) inefficient autophagosome-lysosome fusion; (3) inefficient degradation of the autophagic vesicles in the lysosome. Examples of diseases for which alterations in each autophagic step have been described are shown. AD, Alzheimer's disease; ALS, Amyotrophic lateral sclerosis; HD, Huntington's disease; PD, Parkinson's disease.