Bo K. Siesjö reviews the mechanisms of brain cell damage, emphasizing the role of cellular energy failure and ion fluxes. Brain cells, particularly neurons, are vulnerable due to their high metabolic demands and limited energy storage. Conditions like stroke and head trauma can lead to cell death, with ischemia, hypoglycemia, and status epilepticus being major contributors. These conditions disrupt cellular energy homeostasis, leading to ion imbalances and mitochondrial dysfunction. Neurons rely on a complex network of organelles and transport systems to maintain function, and disruptions in these systems can result in severe damage. The paper discusses the role of ion fluxes, mitochondrial ion transport, and the impact of metabolic perturbations on neuronal function. It also highlights the importance of glial cells in maintaining ionic balance and supporting neuronal function. The review covers the effects of various insults on brain cells, including the severity and duration of these insults, and the resulting histopathological changes. The paper concludes that understanding these mechanisms is crucial for developing strategies to prevent or treat brain cell damage.Bo K. Siesjö reviews the mechanisms of brain cell damage, emphasizing the role of cellular energy failure and ion fluxes. Brain cells, particularly neurons, are vulnerable due to their high metabolic demands and limited energy storage. Conditions like stroke and head trauma can lead to cell death, with ischemia, hypoglycemia, and status epilepticus being major contributors. These conditions disrupt cellular energy homeostasis, leading to ion imbalances and mitochondrial dysfunction. Neurons rely on a complex network of organelles and transport systems to maintain function, and disruptions in these systems can result in severe damage. The paper discusses the role of ion fluxes, mitochondrial ion transport, and the impact of metabolic perturbations on neuronal function. It also highlights the importance of glial cells in maintaining ionic balance and supporting neuronal function. The review covers the effects of various insults on brain cells, including the severity and duration of these insults, and the resulting histopathological changes. The paper concludes that understanding these mechanisms is crucial for developing strategies to prevent or treat brain cell damage.