This study investigates the effects of overexpressing interleukin 6 (IL-6) in the central nervous system (CNS) using transgenic mice. The IL-6 gene was targeted to astrocytes via a fusion with the glial fibrillary acidic protein (GFAP) promoter. Transgenic mice with high levels of IL-6 expression developed severe neurological disorders characterized by running, tremors, ataxia, and seizures. Neuropathological findings included neurodegeneration, astrocytosis, angiogenesis, and increased production of acute-phase proteins. These results suggest that cytokines like IL-6 can have a direct pathogenic role in inflammatory, infectious, and neurodegenerative CNS diseases. The study also highlights the potential of using transgenic models to explore the role of cytokines in CNS pathologies.This study investigates the effects of overexpressing interleukin 6 (IL-6) in the central nervous system (CNS) using transgenic mice. The IL-6 gene was targeted to astrocytes via a fusion with the glial fibrillary acidic protein (GFAP) promoter. Transgenic mice with high levels of IL-6 expression developed severe neurological disorders characterized by running, tremors, ataxia, and seizures. Neuropathological findings included neurodegeneration, astrocytosis, angiogenesis, and increased production of acute-phase proteins. These results suggest that cytokines like IL-6 can have a direct pathogenic role in inflammatory, infectious, and neurodegenerative CNS diseases. The study also highlights the potential of using transgenic models to explore the role of cytokines in CNS pathologies.