IL6 and central nervous system cancer: It has also been demonstrated in methamphetamine-administered rats that melatonin prevents drug-induced structural impairments in the BBB, along with decrements in the pro-inflammatory cytokines such as IL-1β, interleukin-6 (IL-6), TNF-α, NF-κB and nuclear factor erythroid 2-related factor (Nrf2) signaling, which are involved in antioxidant defense [118]; these same actions have been documented in glioma cell lines [119] and human neuroblastoma cells [120].