Schematic of the correlation among various cells and tissue components in the brain physiome. The neuron, the oligodendrocyte (OLG), the astrocyte, the endothelial cell (EC) and the microglia (MG) gather to form a neural circuit, myelination, the BBB and the immune system, leading to the prediction of neurotoxicity, neurodegeneration and neuroinflammation as drug side effects on the brain physiome.