In vitro methods in autophagy research: Applications in neurodegenerative diseases and mood disorders

Abstract

BackgroundAutophagy is a conserved physiological intracellular mechanism responsible for the degradation and recycling of cytoplasmic constituents (e.g., damaged organelles, and protein aggregates) to maintain cell homeostasis. Aberrant autophagy has been observed in neurodegenerative diseases, including Alzheimer’s Disease (AD), Parkinson’s Disease (PD), Amyotrophic Lateral Sclerosis (ALS), and Huntington’s Disease (HD), and recently aberrant autophagy has been associated with mood disorders, such as depression. Several in vitro methods have been developed to study the complex and tightly regulated mechanisms of autophagy. In vitro methods applied to autophagy research are used to identify molecular key players involved in dysfunctional autophagy and to screen autophagy regulators with therapeutic applications in neurological diseases and mood disorders. Therefore, the aims of this narrative review are (1) to compile information on the cell-based methods used in autophagy research, (2) to discuss their application, and (3) to create a catalog of traditional and novel in vitro methods applied in neurodegenerative diseases and depression.MethodsPubmed and Google Scholar were used to retrieve relevant in vitro studies on autophagy mechanisms in neurological diseases and depression using a combination of search terms per mechanism and disease (e.g., “macroautophagy” and “Alzheimer’s disease”). A total of 37 studies were included (14 in PD, 8 in AD, 5 in ALS, 5 in %, and 5 in depression).ResultsA repertoire of traditional and novel approaches and techniques was compiled and discussed. The methods used in autophagy research focused on the mechanisms of macroautophagy, microautophagy, and chaperone-mediated autophagy. The in vitro tools presented in this review can be applied to explore pathophysiological mechanisms at a molecular level and to screen for potential therapeutic agents and their mechanism of action, which can be of great importance to understanding disease biology and potential therapeutic options in the context of neurodegenerative disorders and depression.ConclusionThis is the first review to compile, discuss, and provide a catalog of traditional and novel in vitro models applied to neurodegenerative disorders and depression.

Screening and identification of key biomarkers associated with amyotrophic lateral sclerosis and depression using bioinformatics

“…[32] New evidence suggests that there are many common pathogenic factors between ALS and depression, such as excessive apoptosis of post-mitotic cells, endocrine-disrupting chemicals (EDCs), changes in brain-derived neurotrophic factor (BDNF) levels in blood and the central nervous system, insulin resistance, and autophagy regulation. [33,34] Moreover, Young CA and others used a multi-attribute study to determine the prevalence of depression in ALS patients and found it to be common, affecting nearly a quarter of the large study population. 71.8% of comorbid depression patients developed it within 3 years of the ALS diagnosis.…”