The selfish brain: competition for energy resources.

Area of Science:

• Neuroscience
• Metabolic Regulation
• Endocrinology

Background:

• The brain, with high energy demands and limited storage, requires precise regulation of its adenosine triphosphate (ATP) concentration.
• Existing models do not fully explain the brain's priority in energy management over peripheral tissues.
• The blood-brain barrier isolates the brain, necessitating unique mechanisms for nutrient supply and energy homeostasis.

Purpose of the Study:

• To present a new paradigm for organismal energy supply regulation, emphasizing the brain's primary role.
• To elucidate the mechanisms by which the brain ensures its own ATP concentration.
• To explore the connection between brain energy regulation, the limbic-hypothalamus-pituitary-adrenal (LHPA) system, and the pathogenesis of eating disorders.

Main Methods:

• Investigated the role of ATP-sensitive potassium channels in neocortical neurons for sensing ATP levels.
• Examined the function of mineralocorticoid and glucocorticoid receptors in setting the LHPA system's balance point.
• Proposed a model integrating neocortical and LHPA system functions in nutrient allocation and energy homeostasis.

Main Results:

• The brain actively regulates its ATP concentration by controlling nutrient allocation between neural and peripheral tissues.
• A 'glutamate command' signal, originating from neocortical ATP sensing, influences glucose uptake locally and systemically.
• The LHPA system's setpoint, determined by high- and low-affinity receptors, can be pathologically altered by various stressors, impacting energy balance and body mass.

Conclusions:

• The 'Selfish Brain Theory' posits that the brain prioritizes its energy supply, influencing peripheral metabolism.
• A 'principle of balance' involving pairs of high- and low-affinity receptors governs biological setpoints.
• Dysregulation in brain energy management and the LHPA system is implicated in the development of anorexia nervosa and obesity.