Limits...
The selfish brain: stress and eating behavior.

Peters A, Kubera B, Hubold C, Langemann D - Front Neurosci (2011)

Bottom Line: Furthermore psychosocial stress elicits a marked increase in eating behavior in the post-stress phase.Subjects ingested more carbohydrates without any preference for sweet ingredients.These experimentally observed changes of cerebral demand, supply and need are integrated into a logistic framework describing the supply chain of the selfish brain.

View Article: PubMed Central - PubMed

Affiliation: Medical Clinic 1, University of Luebeck Luebeck, Germany.

ABSTRACT
The brain occupies a special hierarchical position in human energy metabolism. If cerebral homeostasis is threatened, the brain behaves in a "selfish" manner by competing for energy resources with the body. Here we present a logistic approach, which is based on the principles of supply and demand known from economics. In this "cerebral supply chain" model, the brain constitutes the final consumer. In order to illustrate the operating mode of the cerebral supply chain, we take experimental data which allow assessing the supply, demand and need of the brain under conditions of psychosocial stress. The experimental results show that the brain under conditions of psychosocial stress actively demands energy from the body, in order to cover its increased energy needs. The data demonstrate that the stressed brain uses a mechanism referred to as "cerebral insulin suppression" to limit glucose fluxes into peripheral tissue (muscle, fat) and to enhance cerebral glucose supply. Furthermore psychosocial stress elicits a marked increase in eating behavior in the post-stress phase. Subjects ingested more carbohydrates without any preference for sweet ingredients. These experimentally observed changes of cerebral demand, supply and need are integrated into a logistic framework describing the supply chain of the selfish brain.

No MeSH data available.


Related in: MedlinePlus

Flow chart showing allocative brain-pull mechanisms. The stress system fulfills brain-pull function (yellow area). It allows the brain to actively demand energy from the body. The stress system is hierarchically organized. At the level of the cerebral hemispheres, amygdala neurons convey an energy-on-demand signal via glutamatergic input into the VMH and the paraventricular nucleus (PVN). With activation of these nuclei at the hypothalamic level, the sympathetic nervous system (SNS) and the hypothalamus pituitary adrenal (HPA) systems are stimulated. These hypothalamic nuclei act via autonomic efferences and via cortisol upon the level of the autonomic viscero- and endocrine secretomotoneurons, i.e., they suppress beta cell insulin secretion. Cerebral insulin suppression (CIS) results in an increased ratio of GLUT1- to GLUT4-mediated glucose uptake. While insulin stimulates (insulin-dependent) GLUT4-mediated glucose uptake into muscle and fat tissue, it does not affect (insulin-independent) GLUT1-mediated glucose uptake across the blood–brain barrier. In this way, brain-pull mechanisms favor glucose fluxes directed toward the brain. There are three feedback loops tuning the brain-pull activity. First, intraneuronal ATP exerts negative feedback at the level of the VMH in order to limit further energy demand. Second, leptin which indicates the energy fill content in muscle and fat exerts positive feedback on VMH-neurons. Third, the stress system is a self-organizing system which optimizes its brain-pull function under the feedback influence of cortisol released from the adrenals. Cortisol exerts feedback inhibition at the hypothalamic level (PVN), and also modulates the processes of long-term potentiation and long-term depression at synapses which convey cerebral input signal directed to the amygdala neurons. In all, the brain-pull system is a hierarchically self-organized feedback-control system which matches the brain's energy supply with the cerebral energy needs.
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Figure 2: Flow chart showing allocative brain-pull mechanisms. The stress system fulfills brain-pull function (yellow area). It allows the brain to actively demand energy from the body. The stress system is hierarchically organized. At the level of the cerebral hemispheres, amygdala neurons convey an energy-on-demand signal via glutamatergic input into the VMH and the paraventricular nucleus (PVN). With activation of these nuclei at the hypothalamic level, the sympathetic nervous system (SNS) and the hypothalamus pituitary adrenal (HPA) systems are stimulated. These hypothalamic nuclei act via autonomic efferences and via cortisol upon the level of the autonomic viscero- and endocrine secretomotoneurons, i.e., they suppress beta cell insulin secretion. Cerebral insulin suppression (CIS) results in an increased ratio of GLUT1- to GLUT4-mediated glucose uptake. While insulin stimulates (insulin-dependent) GLUT4-mediated glucose uptake into muscle and fat tissue, it does not affect (insulin-independent) GLUT1-mediated glucose uptake across the blood–brain barrier. In this way, brain-pull mechanisms favor glucose fluxes directed toward the brain. There are three feedback loops tuning the brain-pull activity. First, intraneuronal ATP exerts negative feedback at the level of the VMH in order to limit further energy demand. Second, leptin which indicates the energy fill content in muscle and fat exerts positive feedback on VMH-neurons. Third, the stress system is a self-organizing system which optimizes its brain-pull function under the feedback influence of cortisol released from the adrenals. Cortisol exerts feedback inhibition at the hypothalamic level (PVN), and also modulates the processes of long-term potentiation and long-term depression at synapses which convey cerebral input signal directed to the amygdala neurons. In all, the brain-pull system is a hierarchically self-organized feedback-control system which matches the brain's energy supply with the cerebral energy needs.

Mentions: Furthermore, mechanisms, given in more detail beneath, which exert “allocative brain-pull mechanism” have been experimentally located (Figure 2). Such mechanisms are capable of limiting peripheral energy storage in favor of the brain. Those experiments have sustained the “Selfish Brain” theory, whose foundations have been laid from 1998 to 2004 (Peters et al., 2004), postulating the existence of such allocative mechanisms and implementing them as functional elements serving to maintain the brain's high energy content at the expense of the body. According to that concept, the brain simultaneously represents the highest regulatory authority and the consumer with the highest priority – it looks after itself first. In this respect, a competition among all organs drives energy allocation. In the following, we take a closer look at the mechanisms that can fulfill the function of allocative brain-pull.


The selfish brain: stress and eating behavior.

Peters A, Kubera B, Hubold C, Langemann D - Front Neurosci (2011)

Flow chart showing allocative brain-pull mechanisms. The stress system fulfills brain-pull function (yellow area). It allows the brain to actively demand energy from the body. The stress system is hierarchically organized. At the level of the cerebral hemispheres, amygdala neurons convey an energy-on-demand signal via glutamatergic input into the VMH and the paraventricular nucleus (PVN). With activation of these nuclei at the hypothalamic level, the sympathetic nervous system (SNS) and the hypothalamus pituitary adrenal (HPA) systems are stimulated. These hypothalamic nuclei act via autonomic efferences and via cortisol upon the level of the autonomic viscero- and endocrine secretomotoneurons, i.e., they suppress beta cell insulin secretion. Cerebral insulin suppression (CIS) results in an increased ratio of GLUT1- to GLUT4-mediated glucose uptake. While insulin stimulates (insulin-dependent) GLUT4-mediated glucose uptake into muscle and fat tissue, it does not affect (insulin-independent) GLUT1-mediated glucose uptake across the blood–brain barrier. In this way, brain-pull mechanisms favor glucose fluxes directed toward the brain. There are three feedback loops tuning the brain-pull activity. First, intraneuronal ATP exerts negative feedback at the level of the VMH in order to limit further energy demand. Second, leptin which indicates the energy fill content in muscle and fat exerts positive feedback on VMH-neurons. Third, the stress system is a self-organizing system which optimizes its brain-pull function under the feedback influence of cortisol released from the adrenals. Cortisol exerts feedback inhibition at the hypothalamic level (PVN), and also modulates the processes of long-term potentiation and long-term depression at synapses which convey cerebral input signal directed to the amygdala neurons. In all, the brain-pull system is a hierarchically self-organized feedback-control system which matches the brain's energy supply with the cerebral energy needs.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3105244&req=5

Figure 2: Flow chart showing allocative brain-pull mechanisms. The stress system fulfills brain-pull function (yellow area). It allows the brain to actively demand energy from the body. The stress system is hierarchically organized. At the level of the cerebral hemispheres, amygdala neurons convey an energy-on-demand signal via glutamatergic input into the VMH and the paraventricular nucleus (PVN). With activation of these nuclei at the hypothalamic level, the sympathetic nervous system (SNS) and the hypothalamus pituitary adrenal (HPA) systems are stimulated. These hypothalamic nuclei act via autonomic efferences and via cortisol upon the level of the autonomic viscero- and endocrine secretomotoneurons, i.e., they suppress beta cell insulin secretion. Cerebral insulin suppression (CIS) results in an increased ratio of GLUT1- to GLUT4-mediated glucose uptake. While insulin stimulates (insulin-dependent) GLUT4-mediated glucose uptake into muscle and fat tissue, it does not affect (insulin-independent) GLUT1-mediated glucose uptake across the blood–brain barrier. In this way, brain-pull mechanisms favor glucose fluxes directed toward the brain. There are three feedback loops tuning the brain-pull activity. First, intraneuronal ATP exerts negative feedback at the level of the VMH in order to limit further energy demand. Second, leptin which indicates the energy fill content in muscle and fat exerts positive feedback on VMH-neurons. Third, the stress system is a self-organizing system which optimizes its brain-pull function under the feedback influence of cortisol released from the adrenals. Cortisol exerts feedback inhibition at the hypothalamic level (PVN), and also modulates the processes of long-term potentiation and long-term depression at synapses which convey cerebral input signal directed to the amygdala neurons. In all, the brain-pull system is a hierarchically self-organized feedback-control system which matches the brain's energy supply with the cerebral energy needs.
Mentions: Furthermore, mechanisms, given in more detail beneath, which exert “allocative brain-pull mechanism” have been experimentally located (Figure 2). Such mechanisms are capable of limiting peripheral energy storage in favor of the brain. Those experiments have sustained the “Selfish Brain” theory, whose foundations have been laid from 1998 to 2004 (Peters et al., 2004), postulating the existence of such allocative mechanisms and implementing them as functional elements serving to maintain the brain's high energy content at the expense of the body. According to that concept, the brain simultaneously represents the highest regulatory authority and the consumer with the highest priority – it looks after itself first. In this respect, a competition among all organs drives energy allocation. In the following, we take a closer look at the mechanisms that can fulfill the function of allocative brain-pull.

Bottom Line: Furthermore psychosocial stress elicits a marked increase in eating behavior in the post-stress phase.Subjects ingested more carbohydrates without any preference for sweet ingredients.These experimentally observed changes of cerebral demand, supply and need are integrated into a logistic framework describing the supply chain of the selfish brain.

View Article: PubMed Central - PubMed

Affiliation: Medical Clinic 1, University of Luebeck Luebeck, Germany.

ABSTRACT
The brain occupies a special hierarchical position in human energy metabolism. If cerebral homeostasis is threatened, the brain behaves in a "selfish" manner by competing for energy resources with the body. Here we present a logistic approach, which is based on the principles of supply and demand known from economics. In this "cerebral supply chain" model, the brain constitutes the final consumer. In order to illustrate the operating mode of the cerebral supply chain, we take experimental data which allow assessing the supply, demand and need of the brain under conditions of psychosocial stress. The experimental results show that the brain under conditions of psychosocial stress actively demands energy from the body, in order to cover its increased energy needs. The data demonstrate that the stressed brain uses a mechanism referred to as "cerebral insulin suppression" to limit glucose fluxes into peripheral tissue (muscle, fat) and to enhance cerebral glucose supply. Furthermore psychosocial stress elicits a marked increase in eating behavior in the post-stress phase. Subjects ingested more carbohydrates without any preference for sweet ingredients. These experimentally observed changes of cerebral demand, supply and need are integrated into a logistic framework describing the supply chain of the selfish brain.

No MeSH data available.


Related in: MedlinePlus