Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Reduced body temperature extends lifespan in study from the Scripps Research Institute

06.11.2006
Lifespan lengthened without dietary restriction

"Our study shows it is possible to increase lifespan in mice by modest but prolonged lowering of core body temperature," said Bruno Conti, an associate professor at Scripps Research who led the study. "This longer lifespan was attained independent of calorie restriction."

Prior to this study, researchers had known that core body temperature and aging were related in cold-blooded animals. Scientists had also known that lifespan could be extended in warm-blooded animals by reducing the number of calories they consumed, which also lowered core body temperature. But the degree of calorie restriction needed to extend lifespan is not easy to achieve, even in mice.

Prior to the current study, critical questions about the relation between calorie restriction, core body temperature, and lifespan remained unanswered. Was calorie restriction itself responsible for longer lifespan, with reduced body temperature simply a consequence? Or was the reduction of core body temperature a key contributor to the beneficial effects of calorie restriction? Conti and colleagues wanted to find out.

To tackle the problem, the scientists decided to try to lower core body temperature directly, without restricting food intake. In cold-blooded animals, such as roundworms (C. elegans) and fruitflies (Drosophila), this task is straight-forward--core body temperature can be lowered simply by changing the temperature of the environment. But for warm-blooded animals, the task is much more challenging.

Conti and colleagues decided to focus their efforts on the preoptic area of the hypothalamus, a structure in the brain that acts as the body's thermostat and is crucial to temperature regulation. Just as holding something warm near the thermostat in a room can fool it into thinking that the entire room is hotter so that the air conditioning turns on, the Scripps Research team reasoned that they could reset the brain's thermostat by producing heat nearby.

To do so, they created a mouse model that produced large quantities of uncoupling protein 2 in hypocretin neurons in the lateral hypothalamus, which is near the preoptic area. The action of uncoupling protein 2 produced heat, which diffused to other brain structures, including the preoptic area. And, indeed, the extra heat worked to induce a continuous reduction of the core body temperature of the mice, lowering it from 0.3 to 0.5 degrees Celsius.

The scientists were then able to measure the effect of lowered core body temperature on lifespan, finding that the mice with lowered core body temperature had significantly longer median lifespan than those that didn't. While this effect was observed in both males and females, in this study the change was more pronounced in females-median lifespan was extended about 20 percent in females and about 12 percent in males.

The researchers performed several experiments to make sure that other factors were not contributing to the lowered core body temperature. They confirmed that the experimental mice were normal in their ability to generate fever, and that these mice moved around about the same amount as normal mice. In addition, the researchers verified that the hypocretin neurons producing uncoupling protein 2 were not involved in temperature regulation.

Importantly, the mice in this study were allowed to eat as much food as they wished, and the experimental and control mice ate the same amount. The weight of the female experimental and control mice did not differ significantly. However, experimental male mice weighed about 10 percent more than the control group, most likely reflecting the reduced energy required to maintain a lower core body temperature, according to the paper.

"Our model addresses something more basic than the amount of food," said Tamas Bartfai, who is chair of the Molecular and Integrative Neurosciences Department, director of the Harold L. Dorris Neurological Research Center at Scripps Research, and an author of the paper. "It works at the level of the thermoregulatory set point that is governed by intra-brain temperature and neurotransmitters. This mechanism, we believe, will be a good target for pharmacological manipulation or heating."

The idea to manipulate the temperature set-point came when Conti and Bartfai joined Scripps Research in the year 2000. Both scientists share common interests in neuroimmunology and the mechanisms of fever. It took over five years of work to conclude this study.

The researchers are now working to identify the precise mechanisms that are responsible for the beneficial effects of reduced core body temperature. They are also investigating whether their findings can be applied to research on obesity.

Keith McKeown | EurekAlert!
Further information:
http://www.scripps.edu

More articles from Health and Medicine:

nachricht Scientists learn more about how gene linked to autism affects brain
19.06.2018 | Cincinnati Children's Hospital Medical Center

nachricht Overdosing on Calcium
19.06.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Carbon nanotube optics provide optical-based quantum cryptography and quantum computing

19.06.2018 | Physics and Astronomy

How to track and trace a protein: Nanosensors monitor intracellular deliveries

19.06.2018 | Life Sciences

New material for splitting water

19.06.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>