Neural Metabolic Networks: Key Elements of Healthy Brain Function.

Neural networks are responsible for processing sensory stimuli and driving the synaptic activity required for brain function and behavior. This computational capacity is expensive and requires a steady supply of energy and building blocks to operate. Importantly, the neural networks are composed of different cell populations, whose metabolic profiles differ between each other, thus endowing them with different metabolic capacities, such as, for example, the ability to synthesize specific metabolic precursors or variable proficiency to manage their metabolic waste. These marked differences likely prompted the emergence of diverse intercellular metabolic interactions, in which the shuttling and cycling of specific metabolites between brain cells allows the separation of workload and efficient control of energy demand and supply within the central nervous system. Nevertheless, our knowledge about brain bioenergetics and the specific metabolic adaptations of neural cells still warrants further studies. In this review, originated from the Fourth International Society for Neurochemistry (ISN) and Journal of Neurochemistry (JNC) Flagship School held in Schmerlenbach, Germany (2022), we describe and discuss the specific metabolic profiles of brain cells, the intercellular metabolic exchanges between these cells, and how these bioenergetic activities shape synaptic function and behavior. Furthermore, we discuss the potential role of faulty brain metabolic activity in the etiology and progression of Alzheimer's disease, Parkinson disease, and Amyotrophic lateral sclerosis. We foresee that a deeper understanding of neural networks metabolism will provide crucial insights into how higher-order brain functions emerge and reveal the roots of neuropathological conditions whose hallmarks include impaired brain metabolic function.