Central regulation of energy homeostasis intelligent design: how to build the perfect survivor

Neurology Service, VA Medical Center, 385 Tremont Avenue, East Orange, NJ 07018-1095, USA.
Obesity (Impact Factor: 4.39). 09/2006; 14 Suppl 5(supplement 5):192S-196S. DOI: 10.1038/oby.2006.307
Source: PubMed

ABSTRACT The perfect survivor must be able to eat and store as many calories as possible when food is readily available as a buffer against periods of scarcity. He must also reduce energy expenditure when food is scarce and efficiently and accurately restore lost adipose stores when food is again available. These processes are dependent on information relayed to a distributed central network of metabolic sensing neurons through hard-wired neural, metabolic, and hormonal signals from the periphery. These sensing neurons engage neuroendocrine, autonomic, and motor processes involved in arousal, motor activity, and the ingestion, absorption, assimilation, storage, and expenditure of calories. A raised threshold in these metabolic sensors for detecting inhibitory signals from increasing adipose stores allows continued intake of excess calories when they are readily available. Unfortunately, this mechanism for surviving periods of feast and famine predisposes the perfect survivor to become obese when highly palatable, energy dense foods are readily available at low energetic cost. It further assures that raised adipose stores are metabolically defended against attempts to lower them. Thus, effective treatment of obesity will only come with a better understanding of the physiological, metabolic, and neurochemical processes that ensure this defense of an elevated body weight.

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    • "The mechanisms underlying obesity, fat mass development and the development of inflammation are not fully defined. Over the past decade, the physiological processes regulating body weight and energy homeostasis, including peripheral and central food intake regulatory signals and their integration, have received intense investigation (Small & Bloom, 2004; Wynne et al., 2005; Levin, 2006; Chaudhri et al., 2008; Neary & Batterham, 2009). In the present review, we will discuss the importance in obesity of one specific environmental factor that evolves with us and our dietary habits from birth to death, namely the gut microbiota. "
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    • "Active ongoing research over recent years is demonstrating that energy homeostasis is a much more complex, distributed, integrated circuitry involving the hypothalamus as well as other parts of the brain, the brain stem, peripheral tissues particularly adipose tissue and the digestive system that interact with a large number of different interacting signaling molecules including metabolites (Berthoud 2006; Schwartz 2006; Levin 2006; Blundell 2006; Moran 2006 "
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