Administration of exogenous PEA in old mice prior to infection effectively alleviated the excessive systemic release of pro-inflammatory mediators (IL-6, IL-1β, CXCL1, and MIP-1α), which are known to cause cerebral edema, vasculitis, and neuronal and axonal injury, leading to death or long-term sequelae in meningitis patients (48). The gene discussed is CXCL1; the disease is brain edema.