GFAP and Encephalopathy: Zeng et al. [125] recently demonstrated that rapamycin has strong efficacy for preventing seizures and prolonging survival in Tsc1GFAPCKO mice, a mouse model of TSC with conditional inactivation of the Tsc1 gene in glial fibrillary acidic protein (GFAP)–positive cells (Tsc1GFAPCKO mice), which develops progressive epilepsy, encephalopathy, and premature death, as well as cellular and molecular brain abnormalities likely contributing to epileptogenesis.