Skip to main content

Movement comes with appetite: Insulin supresses orexin

domain-b.com : Healthy eating: Movement comes with appetite:

A body that is provided with food too often gets caught up in the maelstrom of a lack of exercise, obesity and ultimately diabetes. The trigger is a molecular switch that is controlled by insulin, a new study by scientists from ETH Zurich has revealed.

[...]

The key switch player in this is a transcription factor called Foxa2. Transcription factors are proteins that make sure other genes are activated and converted into proteins.

Foxa2 is found in the liver, where it influences fat-burning, but also in two important neuron populations in the hypothalamus - the region of the brain that controls the daily rhythm, sleep, intake of food and sexual behavior. The control element for Foxa2 activity is insulin, in both the liver and the hypothalamus.

If a person or animal ingests food, the beta cells in the pancreas release insulin, which blocks Foxa2. When fasting, there is a lack of insulin and Foxa2 is active. In the brain, the scientists have discovered, Foxa2 assists the formation of two proteins: MCH and orexin.

[...]

These two brain messenger substances trigger different behaviour patterns: the intake of food and spontaneous movement. If mammals are hungry, they are more alert and physically active. In short, they hunt and look for food. "If you watch a cat or a dog before feeding it, you can see this very clearly", says Stoffel.

Explanation found for lack of movement
The researchers discovered a disorder in obese mice: in these animals, Foxa2 is permanently active, regardless of whether the animals are fasting or full. This explains a well-known but until now unaccountable phenomenon: the lack of movement in obese people and animals.

To prove this, the researchers used a genetic trick to breed mice, in the brains of which Foxa2 is always active, regardless of whether they have just eaten or are fasting.

These mice produce more MCH and orexin and move five times more than normal animals, in which insulin deactivates Foxa2 after eating or which are obese. The genetically modified mice lose fatty tissue and form larger muscles. Their sugar and fat metabolism works flat out and their blood values are considerably improved.

Three meals a day suffice
For Stoffel, the study clearly shows that, "The body needs fasting periods to stay healthy." Moreover, you should make sure you have a good body weight. He therefore doesn't think much of eating many little meals spread out over the day; it is better to eat less frequently but well, and leave room in between to get hungry.

After all, because insulin is released during every meal, thus suppressing Foxa2, the motivation to do physical exercise and burn sugar and fat visibly decreases.

(Original: Silva JP, von Meyenn F, Howell J, Thorens B, Wolfrum C, Stoffel M. "Regulation of adaptive behaviour during fasting by hypothalamic Foxa2". Nature. Epub 2009 December 3, doi: 10.1038/nature08589."

Comments

Popular posts from this blog

Insulin Resistance- cause of ADD, diabetes, narcolepsy, etc etc

Insulin Resistance Insulin Resistance Have you been diagnosed with clinical depression? Heart disease? Type II, or adult, diabetes? Narcolepsy? Are you, or do you think you might be, an alcoholic? Do you gain weight around your middle in spite of faithfully dieting? Are you unable to lose weight? Does your child have ADHD? If you have any one of these symptoms, I wrote this article for you. Believe it or not, the same thing can cause all of the above symptoms. I am not a medical professional. I am not a nutritionist. The conclusions I have drawn from my own experience and observations are not rocket science. A diagnosis of clinical depression is as ordinary as the common cold today. Prescriptions for Prozac, Zoloft, Wellbutrin, etc., are written every day. Genuine clinical depression is a very serious condition caused by serotonin levels in the brain. I am not certain, however, that every diagnosis of depression is the real thing. My guess is that about 10 percent of the people taking ...

Could Narcolepsy be caused by gluten? :: Kitchen Table Hypothesis

Kitchen Table Hypothesis from www.zombieinstitute.net - Heidi's new site It's commonly known that a severe allergy to peanuts can cause death within minutes. What if there were an allergy that were delayed for hours and caused people to fall asleep instead? That is what I believe is happening in people with Narcolepsy. Celiac disease is an allergy to gliadin, a specific gluten protein found in grains such as wheat, barley and rye. In celiac disease the IgA antigliadin antibody is produced after ingestion of gluten. It attacks the gluten, but also mistakenly binds to and creates an immune reaction in the cells of the small intestine causing severe damage. There is another form of gluten intolerance, Dermatitis Herpetiformis, in which the IgA antigliadin bind to proteins in the skin, causing blisters, itching and pain. This can occur without any signs of intestinal damage. Non-celiac gluten sensitivity is a similar autoimmune reaction to gliadin, however it usually involves the...

Blue-blocking Glasses To Improve Sleep And ADHD Symptoms Developed

Blue-blocking Glasses To Improve Sleep And ADHD Symptoms Developed Scientists at John Carroll University, working in its Lighting Innovations Institute, have developed an affordable accessory that appears to reduce the symptoms of ADHD. Their discovery also has also been shown to improve sleep patterns among people who have difficulty falling asleep. The John Carroll researchers have created glasses designed to block blue light, therefore altering a person's circadian rhythm, which leads to improvement in ADHD symptoms and sleep disorders. […] How the Glasses Work The individual puts on the glasses a couple of hours ahead of bedtime, advancing the circadian rhythm. The special glasses block the blue rays that cause a delay in the start of the flow of melatonin, the sleep hormone. Normally, melatonin flow doesn't begin until after the individual goes into darkness. Studies indicate that promoting the earlier release of melatonin results in a marked decline of ADHD symptoms. Bett...