Featured Research

from universities, journals, and other organizations

Fighting sleep: Potential new treatments for deadly sleeping sickness

Date:
January 17, 2013
Source:
University of Georgia
Summary:
While its common name may make it sound almost whimsical, sleeping sickness, or African trypanosomiasis, is in reality a potentially fatal parasitic infection that has ravaged populations in sub-Saharan Africa for decades, and it continues to infect thousands of people every year.

Roberto Docampo is the Barbara and Sanford Orkin/Georgia Research Alliance Eminent Scholar and a professor of cellular biology in the UGA Franklin College of Arts and Sciences.
Credit: Image courtesy of University of Georgia

While its common name may make it sound almost whimsical, sleeping sickness, or African trypanosomiasis, is in reality a potentially fatal parasitic infection that has ravaged populations in sub-Saharan Africa for decades, and it continues to infect thousands of people every year.

Few drugs have been developed to treat sleeping sickness since the 1940s, and those still in use are highly toxic, sometimes causing painful side effects and even death. But researchers at the University of Georgia have made a discovery that may soon lead to new therapies for this critically neglected disease that cause neither the risks nor the pain associated with traditional treatments.

The scientists at UGA's Center for Tropical and Emerging Global Diseases discovered a specific receptor tucked away in an organelle inside the disease-causing trypanosome parasite that regulates the release of calcium, which is responsible for numerous critical cell functions required for parasite growth and replication.

"This receptor is an attractive drug target," said Roberto Docampo, Barbara and Sanford Orkin/Georgia Research Alliance Eminent Scholar and co-author of a paper describing their findings published Jan. 14 in the early edition of the Proceedings of the National Academy of Sciences. "The mechanisms we have identified are critical for the survival of the parasite, so if we can manipulate them, we can stop the infection."

The calcium receptor identified by the researchers serves as a kind of messenger within the parasite, telling it when to secrete specific chemicals, when to divide and when to spread. They hypothesized that disrupting this system would leave the parasites incapable of growing and replicating within their human and animal hosts.

Docampo and his colleagues tested their hypothesis by watching genetically modified versions of the parasitic cell both in laboratory cultures and in mice. In both cases, the genetically altered parasites with dysfunctional calcium receptors were unable to replicate, and mice in the experimental group remained disease free.

"We knew that these organelles were rich in acidic calcium, but it is not until now that we understand how they released the calcium to control cell functions," said Docampo, who is a professor of cellular biology in the UGA Franklin College of Arts and Sciences. "Now that we better understand this critical pathway, we may begin thinking about new therapies for sleeping sickness."

The parasite is transmitted through the bite of the tsetse fly, a large flying insect found throughout the midcontinent of Africa that survives by drinking blood from human and animal hosts. Many previous global efforts to prevent transmission of sleeping sickness have focused on controlling or eradicating the tsetse fly, which has proven difficult.

Even when humans are successful in avoiding the bite of the tsetse fly, domesticated animals like cattle and pigs may fall victim to nagana, the animal version of sleeping sickness, which, when translated from Zulu, means "depressed in spirit." As the name implies, infected animals lose strength, do not produce milk and eventually die.

"We hear calls all the time for these countries in Africa to become more self-sufficient, but animal sleeping sickness has made it very difficult for many people in this region to establish strong agriculture," Docampo said. "We hope that potential therapies will be equally applicable to animals, and that it will have a positive impact on the area's economic outlook."

Docampo and his colleagues are also confident that their discovery will have applications beyond the treatment of sleeping sickness. Although the cells within humans and animals are more complex than trypanosomes, they do carry organelles that function in similar ways to the ones they hope to block in the parasite.

In research conducted with colleagues at the University of Illinois at Urbana-Champaign, Docampo found that the human version of these organelles plays an important role in blood clotting, which may lead to new therapies for uncontrollable bleeding and trauma.

"These are fundamental discoveries about cell life and function," Docampo said. "We will continue investigating the various roles this organelle plays in our lives and in the lives of other organisms, and we hope that these will lead to new therapies for a variety of disorders."

Other authors of the report include Guozhong Hwang, assistant research scientist, and Silvia N.J. Moreno, professor of cellular biology, both members of the CTEGD, and Paula J. Bartlett and Andrew P. Thomas from the New Jersey Medical School, Newark, N.J.


Story Source:

The above story is based on materials provided by University of Georgia. The original article was written by James Hataway. Note: Materials may be edited for content and length.


Journal Reference:

  1. G. Huang, P. J. Bartlett, A. P. Thomas, S. N. J. Moreno, R. Docampo. Acidocalcisomes of Trypanosoma brucei have an inositol 1,4,5-trisphosphate receptor that is required for growth and infectivity. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1216955110

Cite This Page:

University of Georgia. "Fighting sleep: Potential new treatments for deadly sleeping sickness." ScienceDaily. ScienceDaily, 17 January 2013. <www.sciencedaily.com/releases/2013/01/130117133217.htm>.
University of Georgia. (2013, January 17). Fighting sleep: Potential new treatments for deadly sleeping sickness. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2013/01/130117133217.htm
University of Georgia. "Fighting sleep: Potential new treatments for deadly sleeping sickness." ScienceDaily. www.sciencedaily.com/releases/2013/01/130117133217.htm (accessed July 30, 2014).

Share This




More Plants & Animals News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Raw: Otters Enjoy Water Slides at Japan Zoo

Raw: Otters Enjoy Water Slides at Japan Zoo

AP (July 30, 2014) River otters were hitting the water slides to beat the summer heatwave on Wednesday at Ichikawa City's Zoological and Botanical Garden. (July 30) Video provided by AP
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:
from the past week

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