Stress and obesity: The ghrelin connection

Area of Science:

• Neuroendocrinology
• Metabolic Regulation
• Stress Physiology

Background:

• Ghrelin is a key hormone regulating feeding and energy homeostasis.
• Ghrelin secretion increases during acute stress and remains elevated with chronic stress, accompanied by metabolic shifts.
• These metabolic changes aim to restore homeostatic balance under stress.

Purpose of the Study:

• To review and propose the critical role of ghrelin in stress-induced homeostatic processes.
• To explore ghrelin's influence on appetite, energy expenditure, and fuel utilization during stress.
• To examine ghrelin's impact on reward pathways and stress resilience.

Main Methods:

• Review of existing literature on ghrelin's physiological effects.
• Analysis of ghrelin's neuroanatomical targets involved in stress response.
• Integration of data on ghrelin's metabolic and neuroprotective functions.

Main Results:

• Ghrelin targets the hypothalamus and brain stem, influencing the sympathetic nervous system to increase appetite and energy expenditure.
• It promotes carbohydrate utilization while sparing fat reserves.
• Ghrelin affects mesolimbic regions, modulating reward, protecting against stress-induced damage, and potentially enhancing stress resilience.

Conclusions:

• Ghrelin is a critical metabolic hormone essential for the physiological stress response.
• It plays a significant role in maintaining homeostatic balance during both acute and chronic stress.
• Ghrelin's actions on metabolic and neural pathways highlight its importance in adaptation to stress.