![](http://pinterest.com/pin/create/button/?url=http://trecnews4u.blogspot.com/2014/05/obesitas-apakah-lipid-adalah-obat-keras.html&media=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgpfA3x8YGdlb1Lo-gxYTAS-qQF5aglD0FJZVG3eu8S_zoR9HmZ_LzB67PyJHpE4gGk133z3lCZwfDY5nYgCsu1ujQ37WH_16Bry7xJR3CX0krGmS4BN3pJQetPL4PAtgv7DWUbBUxQ8CzP/s72-c/140415084200-large.jpg&description=..SILAHKAN MENGGUNAKAN " MESIN TRANSLATE "..GOOGLE TRANSLATEÂ DISAMPING KANAN INI............. PLEASE USE ........ " T...){kind=link}
DISAMPING KANAN INI.............
PLEASE USE ........ "TRANSLATE MACHINE" .. GOOGLE TRANSLATE BESIDE RIGHT THIS
..................
Obesity:
Are lipids hard drugs for the brain?
Obesity:
Are lipids hard drugs for the brain?
Date:
April 15,
2014
Source:
CNRS (Délégation Paris Michel-Ange)
Summary:
Why can we get up for a piece of chocolate, but never
because we fancy a carrot? Research has demonstrated part of the answer:
triglycerides, fatty substances from food, may act in our brains directly on
the reward circuit, the same circuit that is involved in drug addiction. These
results show a strong link in mice between fluctuations in triglyceride
concentration and brain reward development. Identifying the action of
nutritional lipids on motivation and the search for pleasure in dietary intake
will help us better understand the causes of some compulsive behaviors and
obesity.
...........................
Why can we get up for a piece of chocolate, but never
because we fancy a carrot? Serge Luquet's team at the "Biologie
Fonctionnelle et Adaptative" laboratory (CNRS/Université Paris Diderot)
has demonstrated part of the answer: triglycerides, fatty substances from food,
may act in our brains directly on the reward circuit, the same circuit that is
involved in drug addiction. These results, published on April 15, 2014 in Molecular Psychiatry,
show a strong link in mice between fluctuations in triglyceride concentration
and brain reward development. Identifying the action of nutritional lipids on
motivation and the search for pleasure in dietary intake will help us better
understand the causes of some compulsive behaviors and obesity.
Though the
act of eating responds to a biological need, it is also an essential cultural
and social function in our modern societies. Meals are generally associated
with a strong notion of pleasure, a feeling that pushes us towards food.
Sometimes this is dangerous: 2.8 million people worldwide die from the consequences
of obesity each year. Fundamentally, obesity is caused by imbalance between
calories consumed and expended. A sedentary life combined with an abundance of
sugary, fatty foods provides fertile ground for this disease.
The body
uses sugars and fats as energy sources. The brain only consumes glucose. So why
do we find an enzyme that can decompose triglycerides, lipids that come in
particular from food, at its core, at the heart of the reward mechanism? A team
at the "Biologie Fonctionnelle et Adaptative" laboratory
(CNRS/Université Paris Diderot) led by Serge Luquet, a CNRS researcher, has
tackled this fundamental question.
If they have
the choice, normal behavior in mice is to prefer a high-fat diet to simpler
foods. To simulate the action of a good meal, researchers have developed an
approach that allows small quantities of lipids to be injected directly into
the brains of mice. They observed that an infusion of triglycerides in the
brain reduces the animal's motivation to press a lever to obtain a food reward.
It also reduces physical activity by half. What is more, an "infused"
mouse balances its diet between the two food sources offered (high-fat foods
and simpler foods).
To ensure
that it is indeed the lipids injected that change the mice's behavior, these
Parisian scientists made sure that the lipids could not be detected by the
animal's brain any longer. They managed to remove the specific enzyme for
triglycerides by silencing its coding gene, but only at the heart of the reward
mechanism. The animal then shows increased motivation to obtain a reward, and
if given the choice, consumes much richer food than average. This work echoes
the previous work by their colleagues[1]: reducing this enzyme in the
hippocampus causes obesity.
Paradoxically,
with obesity, blood (and therefore brain) triglyceride levels are higher than
average. So obesity is often associated with overconsumption of sugary, fatty
foods. The researchers explain this: with long-lasting high exposure to
triglycerides, mice always display lower locomotor activity. By contrast, food
rewards are still attractive! The ideal conditions for weight gain are
therefore in place. At high triglyceride contents, the brain adapts to obtain
its reward, similar to the mechanisms observed when people consume drugs.
Story
Source:
The above
story is based on materials provided by CNRS (Délégation Paris Michel-Ange). Note:
Materials may be edited for content and length.
Journal
Reference:
- Alexandre Picard, Claude Rouch, Nadim Kassis, Valentine S. Moullé, Sophie Croizier, Raphaël G. Denis, Julien Castel, Nicolas Coant, Kathryn Davis, Deborah J. Clegg, Stephen C. Benoit, Vincent Prévot, Sébastien Bouret, Serge Luquet, Hervé Le Stunff, Céline Cruciani-Guglielmacci, Christophe Magnan. Hippocampal lipoprotein lipase regulates energy balance in rodents. Molecular Metabolism, 2014; 3 (2): 167 DOI: 10.1016/j.molmet.2013.11.002
Cite This
Page:
CNRS (Délégation Paris Michel-Ange).
"Obesity: Are lipids hard drugs for the brain?." ScienceDaily.
ScienceDaily, 15 April 2014.
<www.sciencedaily.com/releases/2014/04/140415084200.htm>.
