Featured Research

from universities, journals, and other organizations

Pregnant, constipated and bloated? Fly poo may tell you why

Date:
January 5, 2011
Source:
Wellcome Trust
Summary:
Clues about how the human gut helps regulate our appetite have come from a most unusual source -- fruit fly feces. Scientists are using the fruit fly to help understand aspects of human metabolism, including why pregnant women suffer from bloating and constipation, and even the link between a low calorie diet and longevity.

These are nerve cells in the gut of the Drosophila melanogaster.
Credit: Irene Miguel-Aliaga, University of Cambridge

Clues about how the human gut helps regulate our appetite have come from a most unusual source -- fruit fly faeces. Scientists at the University of Cambridge are using the fruit fly to help understand aspects of human metabolism, including why pregnant women suffer from bloating and constipation, and even the link between a low calorie diet and longevity.

Although scientists have known for some time that there are as many as 500 million nerve cells in our gut, the sheer complexity that this presents means that little is known about the different types of nerve cell and their functions.

Now, researchers led by Dr Irene Miguel-Aliaga, with funding from the Wellcome Trust and the Biotechnology and Biological Sciences Research Council, have used the fruit fly, Drosophila melanogaster, to investigate the function of these intestinal neurons. The fly has simpler versions of our nervous and digestive systems, which lend it to genetic manipulation. Their findings are published in the journal Cell Metabolism.

"We reasoned that what comes out of the gut may be able to tell us about what is going on inside," explains Dr Miguel-Aliaga. "So, we devised a method to extract information about several metabolic features from the flies' faecal deposits -- which are actually rather pretty and don't smell bad. Then we turned specific neurons on and off and examined what came out."

Dr Miguel-Aliaga and colleagues found that these intestinal neurons have very important and specialised functions, such as regulating appetite or adjusting intestinal water balance during reproduction.

Female flies in their reproductive stage get constipated -- their gut emptying rate is reduced even though they are eating more food; at the same time, they retain more water and the contents of their intestines become more concentrated. The researchers showed that these intestinal changes are triggered by the sex peptide, a hormone that males inject into the female during copulation, which activates of a small group of gut neurons. This shares the same function as the sex hormones found in humans, such as progesterone, oxytocin and oestrogen.

"Humans and fruit flies reproduce in very different ways, yet the associated symptoms of constipation and bloating and their cause -- a reproductive hormone -- are the same," explains Dr Miguel-Aliaga. "This suggests that this mechanism has been conserved through evolution. These intestinal changes may provide a benefit at a time of high nutritional demand by maximizing nutrient absorption."

The research also provides tantalising clues about the link between calorie intake and longevity. Intestinal changes which help maximize nutrient absorption would likely be active all the time, as they would provide a selective advantage when food is scarce. However, in flies -- and possibly in humans -- this may come at a cost: a shorter lifespan.

It has been known for some time that when female flies mate and receive the sex peptide, this shortens their lifespan; however, this is not caused entirely by their increased food intake or because they are laying many eggs, the two most obvious effects of this sex peptide. The explanation, argue the researchers, may lie in the intestinal changes triggered by the sex peptide that lead to constipation and water retention.

"A mechanism that maximises nutrient absorption by slowing the passage of food through the intestine is fine when food is scarce or during reproduction," says Dr Miguel-Aliaga, "but when we are eating a normal diet, constipation may lead to the build up of waste products produced during internal metabolism. Similarly, it could lead to changes in the composition of the gut bacteria, which are essential to regulating metabolism.

"Our research suggests that in addition to paying attention to what we eat, which has been the focus of longevity research, we may also have to consider what our body does with the food and what goes on in our guts."


Story Source:

The above story is based on materials provided by Wellcome Trust. Note: Materials may be edited for content and length.


Journal Reference:

  1. Paola Cognigni, Andrew P. Bailey, Irene Miguel-Aliaga. Enteric Neurons and Systemic Signals Couple Nutritional and Reproductive Status with Intestinal Homeostasis. Cell Metabolism, 2011; 13 (1): 92-104 DOI: 10.1016/j.cmet.2010.12.010

Cite This Page:

Wellcome Trust. "Pregnant, constipated and bloated? Fly poo may tell you why." ScienceDaily. ScienceDaily, 5 January 2011. <www.sciencedaily.com/releases/2011/01/110104133907.htm>.
Wellcome Trust. (2011, January 5). Pregnant, constipated and bloated? Fly poo may tell you why. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2011/01/110104133907.htm
Wellcome Trust. "Pregnant, constipated and bloated? Fly poo may tell you why." ScienceDaily. www.sciencedaily.com/releases/2011/01/110104133907.htm (accessed October 2, 2014).

Share This



More Health & Medicine News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pregnancy Spacing Could Have Big Impact On Autism Risks

Pregnancy Spacing Could Have Big Impact On Autism Risks

Newsy (Oct. 1, 2014) A new study says children born less than one year and more than five years after a sibling can have an increased risk for autism. Video provided by Newsy
Powered by NewsLook.com
Robotic Hair Restoration

Robotic Hair Restoration

Ivanhoe (Oct. 1, 2014) A new robotic procedure is changing the way we transplant hair. The ARTAS robot leaves no linear scarring and provides more natural results. Video provided by Ivanhoe
Powered by NewsLook.com
Insertable Cardiac Monitor

Insertable Cardiac Monitor

Ivanhoe (Oct. 1, 2014) A heart monitor the size of a paperclip that can save your life. The “Reveal Linq” allows a doctor to monitor patients with A-Fib on a continuous basis for up to 3 years! Video provided by Ivanhoe
Powered by NewsLook.com
Attacking Superbugs

Attacking Superbugs

Ivanhoe (Oct. 1, 2014) Two weapons hospitals can use to attack superbugs. Scientists in Ireland created a new gel resistant to superbugs, and a robot that can disinfect a room in minutes. Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins