IL1A and Parkinson disease: HSPB1 is highly expressed in astrocytes, is an established regulator of neuroinflammation, as well as demonstrating changes in expression related to both aging and neurodegenerative diseases, including Parkinson’s disease.26 Also reduced in the secretome of TNFα/IL1α/C1q treated ventral midbrain astrocytes were neurodegeneration-implicated proteins, CLU, APOE (minimal reduction) and IQCK27,28 (Fig. 2B).