Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New data on fructose-sweetened beverages and hepatic metabolism

16.03.2007
According to figures published by the World Health Organitzation (WHO), in the year 2015 some 2.3 bn adults will be overweight and more than 700 million will suffer from obesity, a pathology which is increasingly being seen in children.

In addition, for some time now the high incidence of obesity in developed countries has coincided with an increase in the consumption of beverages sweetened with fructose, a powerful sweetener. A team from the University of Barcelona (UB) has recently published a study in the journal Hepatology which provides clues to the molecular mechanism through which the fructose in beverages may alter lipid energy metabolism and cause fatty liver and metabolic syndrome.

The study was led by Dr Juan Carlos Laguna of the Department of Pharmacology and Therapeutic Chemistry at the Faculty of Pharmacy, who is also the director of the research group “Nuclear receptors regulating energy metabolism as pharmacological targets”, with the participation of Núria Roglans, Laia Vilà, Mireia Farré, Marta Alegret, Rosa Mª Sánchez and Manuel Vázquez-Carrera.

This preclinical study published in Hepatology was carried out with laboratory rats receiving fructose- or glucose-sweetened liquid intake. No solid food was given. “The fructose in fruit has nothing to do with this study,” stresses Professor Laguna. “Fruit is healthy and its consumption is strongly recommended. Our study focuses on liquid fructose intake as an addition to the ordinary diet.”

Fructose is mainly metabolized in the liver, the target organ of the metabolic alterations caused by the consumption of this sugar. In this study, rats receiving fructose-containing beverages presented a pathology similar to metabolic syndrome, which in the short term causes lipid accumulation (hypertriglyceridemia) and fatty liver, and at later stages hypertension, resistance to insulin, diabetes and obesity.

The fructose used to sweeten beverages alters the lipid metabolism in the liver and, according to the authors, represents a calorie overload to which the body’s metabolism is unable to adapt. Specifically, fructose increases fat synthesis in the liver and reduces its degradation through action on a specific nuclear receptor (PPARa), which controls fatty acid ß-oxidation. “The most novel finding,” says Laguna, “is that this molecular mechanism is related to an impairment in the leptin signal. Leptin is a hormone that plays a key role in the body’s energy control; among its peripheral actions, it accelerates fat oxidation in the liver and reduces its synthesis.”

The study shows that rats receiving beverages with fructose have an excess of leptin in blood. Curiously, though, the liver does not show the effects that one would expect in the presence of high levels of this hormone. It seems that the deficit in the degradation of the fatty acids in the liver may be related to the leptin resistance, which affects a transcription factor (Stat-3) involved in the signalling pathway of leptin in the liver and the hypothalamus. Nor were significant weight differences found between the rats drinking liquids with glucose or fructose, “possibly because this was a short-term experiment and there was no time to detect such changes,” notes Professor Laguna.

Poorly balanced diets and the lack of physical exercise are key factors in the increase of obesity and other metabolic diseases in modern societies. In epidemiological studies in humans, the effect of the intake of fructose-sweetened beverages seems to be more intense in women. Professor Laguna’s team intends to continue research on a variety of fronts: the study of the difference in response between sexes; the study of the molecular mechanisms of leptin resistance in the liver in rat models; experimental studies with hepatocyte cell cultures, and, further into the future, pilot studies of a fructose-rich diet in humans to find possible markers of metabolic alterations in blood cells.

Rosa Martínez | alfa
Further information:
http://www.ub.edu

Further reports about: Fructose Laguna Leptin beverages liver metabolic metabolism molecular mechanism

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>