Research suggests that astrocytes are the source of tumor necrosis factor (TNF) mediating homeostatic synaptic plasticity. The role of astrocytes and other cells, such as microglia, in brain function and disorder is being explored, with a focus on their potential impact on synaptic transmission and neuroinflammation. The study of astrocytes and cytokines, including TNF, is an area of ongoing research, with implications for understanding brain health and disease.