Leptin  and  Food  Addiction.

Continued of  Chinese  Kitchen  Syndrome.

Author

Prof. Hayk S. Arakelyan. Full Professor in Medicine,

Doctor of Medical Sciences, Ph.D , Grand Ph.D .

Senior Expert of Interactive Clinical Pharmacology , Drug Safety,

Treatment Tactics, General Medicine and Clinical Research.

“Let food be thy medicine, thy medicine shall be thy food.”

“Hippocrates”

Introduction.

Leptin is a hormone predominantly made by adipose cells that helps to regulate energy balance by inhibiting hunger. Leptin is opposed by the actions of the hormone ghrelin, the "hunger hormone". Both hormones act on receptors in the arcuate nucleus of the hypothalamus to regulate appetite to achieve energy homeostasis.

Leptin  and Ghrelin.

Leptin and ghrelin are two hormones that have been recognized to have a major influence on energy balance. Leptin is a mediator of long-term regulation of energy balance, suppressing food intake and thereby inducing weight loss. Ghrelin on the other hand is a fast-acting hormone, seemingly playing a role in meal initiation. As a growing  number of people suffer from obesity, understanding the mechanisms by which various hormones and neurotransmitters have influence on energy balance has been a subject of intensive research. 

The influence of leptin on the dopamine system and implications for ingestive behavior.

Food intake is regulated by many factors, including sensory information, metabolic hormones, and the state of hunger. In modern humans, the drive to eat has proven to be incompatible with the excess food supply present in industrialized societies. Rates of obesity are increasing worldwide. The natural drive to eat, combined with a surplus of readily available food, are together partly responsible for this modern epidemic. In order to understand the source of this problem, we need to better define the molecular and neural mechanisms by which the brain regulates food intake, and why it is often difficult to control food ingestion in times of excess. The discovery that peripheral metabolic hormones, normally studied for their activity in the hypothalamus, act directly on dopamine neurons of brain dopamine centers to modulate feeding behavior, has provided new mechanisms for behavioral control. Here, recent findings are reviewed and with an emphasis on the potential implications as well as open questions that remain.

Glutamate  and  Leptin.

Leptin is a protein secreted by adipocytes that is important in regulating appetite and adiposity. Recent studies have suggested the presence of  leptin receptors in the arcuate nucleus of the hypothalamus (ANH). Neonatal administration of monosodium glutamate (MSG) damages the ANH, resulting in obesity and neuroendocrine dysfunction.

Dopamine D2 receptors in addiction-like reward dysfunction and compulsive eating.

development of obesity was coupled with emergence of a progressively worsening deficit in neural reward responses. Similar changes in reward homeostasis induced by cocaine or heroin are considered to be crucial in triggering the transition from casual to compulsive drug-taking. Accordingly, we detected compulsive-like feeding behavior. Administration of leptin has been shown to modulate behaviors that are dependent upon the mesolimbic dopamine circuit. For  example, leptin administration alters intracranial self-stimulation, suggesting an interaction with dopamine circuits that are thought to underlie the behavior. Other data have demonstrated that leptin attenuates the increased propensity to heroin relapse caused by food restriction (12) and can modulate conditioned place preference for sucrose or high fat food. These data suggest that leptin can modify reward based behavior and that this may occur via alteration in function of dopamine pathways . While this interaction with dopamine pathways could occur downstream from leptin’s effects on the hypothalamus, recent data also suggests a direct action of leptin on dopamine centers of the brain.

-Dopamine and food intake.

-Mutant  Leptins.

- Genetic Aspects and location of genes .

-Leptin ,  ghrelin body weight in humans and Diseases.

-Dopamine, the nucleus accumbens, and hedonics.

-Regulation of glutamate receptor trafficking by leptin.

-Glutamate and GABA in Appetite  Regulation.

-Food Addiction and Drugs.

-Food Addiction and Alcohol.

-Food Addiction and Smoking.

-Food Addiction and Diseases.

-Food Addiction and Brain Performance.

To be continued ....

If you have any questions concerning “ Leptin  and  Food  Addiction.”, interactive clinical pharmacology , or any other questions, please  inform  me .

 Prof. Hayk S. Arakelyan