Relationship Between Obesity, Alzheimer's Disease, and Parkinson's Disease: an Astrocentric View.

Obesity is considered one of the greatest risk to human health and is associated with several factors including genetic components, diet, and physical inactivity. Recently, the relationship between obesity and numerous progressive and aging-related neurodegenerative diseases such as Parkinson's disease (PD) and Alzheimer's disease (AD) have been observed. Thus, the involvement of the most abundant and heterogeneous group of glial cells in neurodegenerative diseases, the astrocytes, is caused by a combination of the failure on their normal homeostatic functions and the increase of toxic metabolites upon pathological event. Upon brain damage, molecular signals induce astrocyte activation and migration to the site of injury, entering in a highly active state, with the aim to contribute to ameliorating or worsening the pathology. In this regard, the aim of this review is to elucidate the relationship between obesity, Alzheimer's disease, and Parkinson's disease and highlight the role of astrocytes in these pathologies.