H2AX and Bilateral tonic-clonic seizure: We found the expression of senescent markers SA-β-Gal, P21, γ-H2AX, and COX2 as well as downregulation of Lamin B1 in cortical neurons in mice that developed chronic focal seizures and generalized tonic-clonic seizures 2 months after kainic acid injection (Supplemental Figure 10), but not in mice 3 days after acute epileptic seizures (Supplemental Figure 9).