Your brain rewards you twice per meal

Your brain rewards you twice per meal: When you eat and when food reaches your stomach

We know a good meal can stimulate the release of the feel-good hormone dopamine, and now a study in humans  suggests that dopamine release in the brain occurs at two different times: at the time the food is first ingested and another once the food reaches the stomach. 

"With the help of a new positron emission tomography (PET) technique we developed, we were not only able to find the two peaks of dopamine release, but we could also identify the specific brain regions that were associated with these releases," says senior author.

 

 "While the first release occurred in brain regions associated with reward and sensory perception, the post-ingestive release involved additional regions related to higher cognitive functions."

 

In the study, 12 healthy volunteers received either a palatable milkshake or a tasteless solution while PET data were recorded. Interestingly, the subjects' craving or desire for the milkshake was proportionally linked to the amount of dopamine released in particular brain areas at the first tasting. But the higher the craving, the less delayed post-ingestive dopamine was released.

 

"On one hand, dopamine release mirrors our subjective desire to consume a food item. On the other hand, our desire seems to suppress gut-induced dopamine release," says group leader, who is co-first author on the study.

 

Suppression of gut-induced release could potentially cause overeating of highly desired food items. "We continue to eat until sufficient dopamine was released," The author says but adds that this hypothesis remains to be tested in further studies.

 

Earlier experiments have demonstrated gut-induced dopamine release in mice, but this is the first time it has been shown in humans.

THIS IS ONLY FOR INFORMATION, ALWAYS CONSULT YOU PHYSICIAN BEFORE HAVING ANY PARTICULAR FOOD/ MEDICATION/EXERCISE/OTHER REMEDIES.                                                                                  PS- THOSE INTERESTED IN RECIPES ARE FREE TO  VIEW MY BLOG-                                                                                           https://gseasyrecipes.blogspot.com/                                                                                                                                                                             FOR INFO ABOUT KNEE REPLACEMENT, YOU CAN VIEW MY BLOG-                                                     https:// kneereplacement-stickclub.blogspot.com/                                                                                        FOR CROCHET DESIGNS                                                                                                                                                                                                              https://gscrochetdesigns.blogspot.com

Just a few drinks may change how memories are formed

Just a few drinks in an evening may change how memories are formed at the fundamental, molecular level, a study suggests.

One of the many challenges with battling alcohol addiction and other substance abuse disorders is the risk of relapse, even after progress towards recovery, said researchers.

Even pesky fruit flies have a hankering for alcohol, and because the molecular signals involved in forming flies' reward and avoidance memories are much the same as those in humans, they are a good model for study, they said.

The study, published in the journal, in flies found that alcohol hijacks this memory formation pathway and changes the proteins expressed in the neurons, forming cravings.

Researchers uncovered the molecular signalling pathways and changes in gene expression involved in making and maintaining reward memories.
 
"One of the things I want to understand is why drugs of abuse can produce really rewarding memories when they're actually neurotoxins," said, an assistant professor. The team used genetic tools to selectively turn off key genes while training the flies where to find alcohol. This enabled them to see what proteins were required for this reward behaviour.

One of the proteins responsible for the flies' preference for alcohol is Notch, the researchers found.
Notch is the first "domino" in a signalling pathway involved in embryo development, brain development and adult brain function in humans and all other animals.

Molecular signalling pathways are not unlike a cascade of dominos -- when the first domino falls (in this case, the biological molecule activates), it triggers more that trigger more and so on.

One of the downstream dominos in the signalling pathway affected by alcohol is a gene called dopamine-2-like receptor, which makes a protein on neurons that recognises dopamine, the "feel-good" neurotransmitter.

"The dopamine-2-like receptor is known to be involved in encoding whether a memory is pleasing or aversive," a researcher  said. Alcohol hijacks this conserved memory pathway to form cravings.

In the case of the alcohol reward pathway studied, the signalling cascade didn't turn the dopamine receptor gene on or off, or increase or decrease the amount of protein made, she said.

Instead, it had a subtler effect -- it changed the version of the protein made by a single amino acid "letter" in an important area.

"We don't know what the biological consequences of that small change are, but one of the important findings from this study is that scientists need to look not only at which genes are being turned on and off, but which forms of each gene are getting turned on and off," she said.

"We think these results are highly likely to translate to other forms of addiction, but nobody has investigated that," she said.

The Prof. is working with an assistant professor , to look at DNA samples from patients with alcohol abuse disorders to see if they have genetic polymorphisms in any of the craving-related genes discovered in flies.

"If this works the same way in humans, one glass of wine is enough to activate the pathway, but it returns to normal within an hour," she said.

"After three glasses, with an hour break in between, the pathway doesn't return to normal after 24 hours. We think this persistence is likely what is changing the gene expression in memory circuits," she said .

"Just something to keep in mind the next time you split a bottle of wine with a friend or spouse," she said.

THIS IS ONLY FOR INFORMATION, ALWAYS CONSULT YOU PHYSICIAN BEFORE HAVING ANY PARTICULAR FOOD/ MEDICATION/EXERCISE/OTHER REMEDIES.                                                                                                                                                                                                       PS- THOSE INTERESTED IN RECIPES ARE FREE TO  VIEW MY BLOG-                                                                                           https://gseasyrecipes.blogspot.com/   

  FOR INFO ABOUT KNEE REPLACEMENT, YOU CAN VIEW MY BLOG-                                                                                          https:// kneereplacement-stickclub.blogspot.com/                              

FOR CROCHET DESIGNS                                                                                                                                                                                                                                 https://gscrochetdesigns.blogspot.com