Contact Information:
Marge Dwyer
mhdwyer@hsph.harvard.edu
617-432-8416
Harvard School of Public Health
@HarvardHSPH



Kredyty mieszkaniowe Kredyty mieszkaniowe

Sprawdź aktualny ranking najlepszych kredytów mieszkaniowych w Polsce - atrakcyjne kredytowanie nieruchomości.
PRESS-NEWS.org - Press Release Distribution
FREE PRESS RELEASES DISTRIBUTION
RSS - Press News Release
Add Press Release

Excessive contact between cellular organelles disrupts metabolism in obesity


2014-11-24
(Press-News.org) Boston, MA - Researchers at Harvard School of Public Health (HSPH) have found a novel mechanism causing type 2 diabetes that could be targeted to prevent or treat the disease. The research highlights a previously unrecognized molecular pathway that contributes to the malfunction of liver cells in obesity, leading to insulin resistance and diabetes.

The study appears online November 24, 2014 in Nature Medicine.

"While it is well-established that obesity generates cellular and molecular stress leading to abnormal functioning of many cellular processes, the mechanisms remain incompletely understood," said senior author Gökhan S. Hotamisligil, chair of the Department of Genetics and Complex Diseases and the Sabri Ülker Center for Nutrient, Genetic, and Metabolic Research. "Our study revealed that one of these mechanisms involves metabolic stress-induced structural changes within liver cells that compromise their function."

The researchers used electron microscopy and other imaging techniques to view thousands of cells from the liver tissue of lean and obese mice. They counted each of the contact points between two cellular organelles -- the endoplasmic reticulum (ER) and mitochondria -- and demonstrated for the first time that the number of these connections, called MAMs, markedly increase during obesity.

Under normal conditions, these connections are necessary for the function of both organelles. However, co-authors Ana Paula Arruda, Benedicte Pers, and colleagues showed that the increased connectivity resulted in an excess of calcium being transferred from the ER to the mitochondria, leading to mitochondrial stress. In an elegant proof-of-principle approach, the researchers used synthetic molecules to decrease the physical distance between the ER and mitochondria in cells and in liver tissue and found that this intervention impaired mitochondrial function and made mice more sensitive to high fat diet-induced insulin resistance and diabetes.

The researchers also demonstrated that by disrupting the ER-mitochondrial interactions and calcium transfer, they could markedly improve the metabolic health of obese diabetic mice -- pointing the way to a potential treatment target in humans. "It turns out that the enhanced MAM formation in obesity is too much of a good thing, leading to functional failure of multiple organelles and amplification of cellular stress," Hotamisligil said.

INFORMATION:

HSPH authors included lead authors Ana Paula Arruda and Benedicte Pers, Günes Parlakgül, Ekin Guney, and Karen Inouye.

This work was supported in part by the National Institutes of Health (DK52539 and 1RC4-DK090942). Ana Paula Arruda is supported by PEW Charitable Trusts. Benedicte Pers is supported by the Alfred Benzon Foundation (Denmark).

"Chronic enrichment of hepatic endoplasmic reticulum-mitochondria contact leads to mitochondrial dysfunction in obesity," Ana Paula Arruda, Benedicte M. Pers, Güneş Parlakgül, Ekin Güney, Karen Inouye, and Gökhan S. Hotamisligil, Nature Medicine, online November 24, 2014, DOI: 10.1038/nm.3735

Harvard School of Public Health brings together dedicated experts from many disciplines to educate new generations of global health leaders and produce powerful ideas that improve the lives and health of people everywhere. As a community of leading scientists, educators, and students, we work together to take innovative ideas from the laboratory to people's lives--not only making scientific breakthroughs, but also working to change individual behaviors, public policies, and health care practices. Each year, more than 400 faculty members at HSPH teach 1,000-plus full-time students from around the world and train thousands more through online and executive education courses. Founded in 1913 as the Harvard-MIT School of Health Officers, the School is recognized as America's oldest professional training program in public health. For more information, visit http://www.hsph.harvard.edu or contact Marge Dwyer, 617-432-8416.

HSPH on Twitter: http://twitter.com/HarvardHSPH

HSPH on Facebook: http://www.facebook.com/harvardpublichealth

HSPH on You Tube: http://www.youtube.com/user/HarvardPublicHealth

HSPH home page: http://www.hsph.harvard.edu


ELSE PRESS RELEASES FROM THIS DATE:

New device could make large biological circuits practical

2014-11-24
CAMBRIDGE, MA -- Researchers have made great progress in recent years in the design and creation of biological circuits -- systems that, like electronic circuits, can take a number of different inputs and deliver a particular kind of output. But while individual components of such biological circuits can have precise and predictable responses, those outcomes become less predictable as more such elements are combined. A team of researchers at MIT has now come up with a way of greatly reducing that unpredictability, introducing a device that could ultimately allow such ...

Pain in a dish

Pain in a dish
2014-11-24
After more than six years of intensive effort, and repeated failures that made the quest at times seem futile, Harvard Stem Cell Institute (HSCI) researchers at Boston Children's Hospital (BCH) and Harvard's Department of Stem Cell and Regenerative Biology (HSCRB) have successfully converted mouse and human skin cells into pain sensing neurons that respond to a number of stimuli that cause acute and inflammatory pain. This "disease in a dish" model of pain reception may advance the understanding of different types of pain, identify why individuals differ in their pain ...

Masking HIV target cells prevents viral transmission in animal model

2014-11-24
Cloaking immune cells with antibodies that block T cell trafficking to the gut can substantially reduce the risk of viral transmission in a non-human primate model of HIV infection, scientists report. The findings suggest that drugs that are already in clinical trials for inflammatory bowel diseases might be effective in the treatment or prevention of HIV infection. The results are scheduled for publication in Nature Medicine. "We were surprised by the effects that we observed," says senior author Aftab Ansari, PhD, professor of pathology and laboratory ...

Animals steal defenses from bacteria

Animals steal defenses from bacteria
2014-11-24
It's a dog eat dog world, and bacteria have been living in it for a long time. It's of no surprise that bacteria have a sophisticated arsenal to compete with each other for valuable resources in the environment. In 2010, work led by University of Washington Department of Microbiology Associate Professor Joseph Mougous uncovered a weaponry system used in this warfare between bacteria. The combatants inject deadly toxins into rival cells. Now, in a surprising twist, Mougous and colleagues have found that many animals have taken a page from the bacterial playbook. They steal ...

Global warming cynics unmoved by extreme weather

Global warming cynics unmoved by extreme weather
2014-11-24
EAST LANSING, Mich. --- What will it take to convince skeptics of global warming that the phenomenon is real? Surely, many scientists believe, enough droughts, floods and heat waves will begin to change minds. But a new study led by a Michigan State University scholar throws cold water on that theory. Only 35 percent of U.S. citizens believe global warming was the main cause of the abnormally high temperatures during the winter of 2012, Aaron M. McCright and colleagues report in a paper published online today in the journal Nature Climate Change. "Many people already ...

Cooling with the coldest matter in the world

Cooling with the coldest matter in the world
2014-11-24
Physicists at the University of Basel have developed a new cooling technique for mechanical quantum systems. Using an ultracold atomic gas, the vibrations of a membrane were cooled down to less than 1 degree above absolute zero. This technique may enable novel studies of quantum physics and precision measurement devices, as the researchers report in the journal Nature Nanotechnology. Ultracold atomic gases are among the coldest objects in existence. Laser beams can be used to trap atoms inside a vacuum chamber and slow down their motion to a crawl, reaching temperatures ...

Italian natural history museums on the verge of collapse?

Italian natural history museums on the verge of collapse?
2014-11-24
Are Italian natural history museums (NHMs) on the verge of collapse? A new analysis published in the open access journal ZooKeys points out that these institutions are facing a critical situation due to progressive loss of scientific relevance, decreasing economic investments and scarcity of personnel. The study proposes that existing museums associate and collaborate to form a diffused structure, able to better manage their scientific collections and share resources and personnel. "Italy is universally known for its history, culture, food and art. The list of Italian ...

New method to determine antibiotic resistance fast

2014-11-24
Scientists from Uppsala University, the Science for Life Laboratory (SciLifeLab) in Stockholm and Uppsala University Hospital have developed a new method of rapidly identifying which bacteria are causing an infection and determining whether they are resistant or sensitive to antibiotics. The findings are now being published in the Journal of Clinical Microbiology. 'Clinical use of the method would mean that the right antibiotic treatment could be started straightaway, reducing unnecessary use of antibiotics,' says Professor Dan I. Andersson of Uppsala University, who ...

Cell's skeleton is never still

Cells skeleton is never still
2014-11-24
HOUSTON - (Nov. 24, 2014) - New computer models that show how microtubules age are the first to match experimental results and help explain the dynamic processes behind an essential component of every living cell, according to Rice University scientists. The results could help scientists fine-tune medications that manipulate microtubules to treat cancer and other diseases. Rice theoretical biophysicist Anatoly Kolomeisky and postdoctoral researcher Xin Li reported their results in the Journal of Physical Chemistry B. Microtubules are cylinders made of 13 protein strands ...

Sleep apnea linked to poor aerobic fitness

2014-11-24
People with moderate to severe obstructive sleep apnea may have an intrinsic inability to burn high amounts of oxygen during strenuous aerobic exercise, according to a new study led by researchers at University of California, San Diego School of Medicine. The study, reported in the current issue of Journal of Clinical Sleep Medicine, shows that people with sleep apnea, in which breathing repeatedly starts and stops during slumber, have a lower peak oxygen uptake during aerobic activity than those who do not suffer from the sleep disorder. People who suffer from apnea ...

LAST 30 PRESS RELEASES:

How your brain decides blame and punishment -- and how it can be changed

Uniquely human brain region enables punishment decisions

Pinpointing punishment

Chapman University publishes research on attractiveness and mating

E-cigarettes: Special issue from Nicotine & Tobacco Research

Placental problems in early pregnancy associated with 5-fold increased risk of OB & fetal disorders

UT study: Invasive brood parasites a threat to native bird species

Criminals acquire guns through social connections

Restoring ocean health

Report: Cancer remains leading cause of death in US Hispanics

Twin study suggests genetic factors contribute to insomnia in adults

To be fragrant or not: Why do some male hairstreak butterflies lack scent organs?

International team discovers natural defense against HIV

Bolivian biodiversity observatory takes its first steps

Choice of college major influences lifetime earnings more than simply getting a degree

Dominant strain of drug-resistant MRSA decreases in hospitals, but persists in community

Synthetic biology needs robust safety mechanisms before real world application

US defense agencies increase investment in federal synthetic biology research

Robots help to map England's only deep-water Marine Conservation Zone

Mayo researchers identify protein -- may predict who will respond to PD-1 immunotherapy for melanoma

How much water do US fracking operations really use?

New approach to mammograms could improve reliability

The influence of citizen science grows despite some resistance

Unlocking secrets of how fossils form

What happens on the molecular level when smog gets into the lungs?

Using ultrasound to clean medical instruments

Platinum and iron oxide working together get the job done

Tiny silica particles could be used to repair damaged teeth, research shows

A quantum lab for everyone

No way? Charity's logo may influence perception of food in package

[Press-News.org] Excessive contact between cellular organelles disrupts metabolism in obesity
Press-News.org is a service of DragonFly Company. All Rights Reserved.
Issuers of news releases are solely responsible for the accuracy of their content.