TNF and neurodegenerative disease: demonstrated that A1 reactive astrocytes are induced by classically‐activated neuroinflammatory microglia through the secretion of IL‐1α, TNF‐α, and C1q, a phenomenon observed in human neurodegenerative diseases such as Alzheimer's, Huntington's, Parkinson's, amyotrophic lateral sclerosis, and multiple sclerosis.[16] While some studies have suggested A1 reactive astrocytes contribute to depression‐like behaviors and memory deficits observed in mice,[8] Liu et al.