TNF and spinocerebellar ataxia type 1: These results suggested that as pathological conditions develop in the SCA1 mice, microglia are activated first and subsequently trigger astrocyte activation through release of ATP and inflammatory mediators such as proinflammatory cytokines (e.g., IL-1, TNFα) or other inflammatory mediators (e.g., prostaglandin E2) [105](Fig. 17).