ABSTRACT
Neurodegenerative disease refers to neuronal loss as the principal pathology associated with disorders such as amyotrophic lateral sclerosis, Alzheimer’s disease, Huntington disease, Batten disease and Parkinson disease. Neurodegeneration often results from cell death and infl ammatory damage in brain areas affected in these diseases. The predominant form of cell death in neurodegenerative diseases is by apoptosis (Smale et al., 1995) but different mechanisms contribute to neuronal loss and disease progression. Accumulation of autophagosomes or disrupted axonal transport are also common features of many neurodegenerative diseases (Anglade et al., 1997; Sapp et al., 1997; Sasaki, 2011; Yu et al., 2005). Autophagic/lysosomal pathways are quality control systems of proteins and organelles in neurons and are essential in both physiological and pathological conditions (Klionsky and Emr, 2000). Dysfunctional autophagy machinery can initiate self-digestion of dying cells (Komatsu et al., 2006) with an inadequate autophagic response increasing vulnerability to stress conditions and induction of cell death (Komatsu et al., 2007; Ravikumar et al., 2005).
