Featured Research

from universities, journals, and other organizations

Scientists use light to uncover the cause of sickle cell disease

Date:
November 5, 2013
Source:
Cell Press
Summary:
In sickle cell disease, hemoglobin -- the oxygen-carrying component of blood -- forms fibers that stiffen red blood cells and cause life-threatening symptoms. Using light-scattering techniques to study the detailed thermodynamics of this process, researchers have determined the strength of the forces that hold these fibers intact. The information could be used to design therapies that interfere with the sickling process.

In sickle cell disease, hemoglobin -- the oxygen-carrying component of blood -- forms fibers that stiffen red blood cells and cause life-threatening symptoms. Using light-scattering techniques to study the detailed thermodynamics of this process, researchers reporting in the November 5 issue of the Biophysical Journal, a Cell Press publication, have determined the strength of the forces that hold these fibers intact. The information could be used to design therapies that interfere with the sickling process.

Red blood cells resemble beanbags whose contents are molecules of hemoglobin that give the cells their "squishiness" by slipping past one another rather than sticking together. This is no easy feat, because the molecules have positive and negative charges spread around their surfaces, as well as oily patches that repel water and thus provide natural partners. Yet it's thought that when two places of mutual attraction meet, locations of repulsion also come together and keep the net sum of attraction at zero.

In rare cases, such as sickle cell disease, a mutation in hemoglobin disrupts this delicate cancellation of attractive spots, and large stiff fibers, or polymers, of hemoglobin form inside normally pliable red blood cells.

Dr. Frank Ferrone, of Drexel University in Philadelphia, and Dr. Yihua Wang, currently at the Mayo Clinic in Rochester, discovered that the cancellation is not as perfect as previously thought, however. In fact, hemoglobin molecules do indeed associate, especially when the temperature is high or when hemoglobin solutions are concentrated. "This is true for normal hemoglobin, and even more pronounced for sickle hemoglobin," says Dr. Ferrone. His team found that under physiological conditions, sickle cell hemoglobin molecules are more likely to be found in pairs than as solitary molecules.

The researchers made these discoveries while conducting experiments with light-scattering techniques: they measured how rays of light are deflected by sickle hemoglobin fibers in order to calibrate the strength of the connections that hold them together. "By comparing the propensity of molecules of sickle hemoglobin to associate into pairs with the propensity of normal hemoglobin to do so, the relative strengths of the two major bonds within the sickle polymer were determined. The sickle cell mutation site was far stronger," Dr. Ferrone explains. "This makes the sickle hemoglobin polymers behave much like long tiny coil springs and helps us to understand their stiffness, which causes so much difficulty for affected individuals."

The findings could lead to new drug therapies that target the regions of hemoglobin that are responsible for polymer formation.


Story Source:

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


Journal Reference:

  1. Wang et al. Dissecting the Energies that Stabilize Sickle Hemoglobin Polymers. Biophysical Journal, November 2013

Cite This Page:

Cell Press. "Scientists use light to uncover the cause of sickle cell disease." ScienceDaily. ScienceDaily, 5 November 2013. <www.sciencedaily.com/releases/2013/11/131105121413.htm>.
Cell Press. (2013, November 5). Scientists use light to uncover the cause of sickle cell disease. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2013/11/131105121413.htm
Cell Press. "Scientists use light to uncover the cause of sickle cell disease." ScienceDaily. www.sciencedaily.com/releases/2013/11/131105121413.htm (accessed September 1, 2014).

Share This




More Health & Medicine News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Liberia Continues Fight Against Ebola

Liberia Continues Fight Against Ebola

AFP (Aug. 30, 2014) Authorities in Liberia try to stem the spread of the Ebola epidemic by raising awareness and setting up sanitation units for people to wash their hands. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

Reuters - US Online Video (Aug. 30, 2014) California lawmakers pass a bill requiring universities to adopt "affirmative consent" language in their definitions of consensual sex, part of a nationwide drive to curb sexual assault on campuses. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
New Drug Could Reduce Cardiovascular Deaths

New Drug Could Reduce Cardiovascular Deaths

Newsy (Aug. 30, 2014) The new drug from Novartis could reduce cardiovascular deaths by 20 percent compared to other similar drugs. Video provided by Newsy
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