Featured Research

from universities, journals, and other organizations

Sweet way to detect prediabetes

Date:
July 9, 2010
Source:
Johns Hopkins Medical Institutions
Summary:
Having discovered a dramatic increase of an easy-to-detect enzyme in the red blood cells of people with diabetes and prediabetes, scientists say the discovery could lead to a simple, routine test for detecting the subtle onset of the disease, before symptoms or complications occur and in time to reverse its course.

Having discovered a dramatic increase of an easy-to-detect enzyme in the red blood cells of people with diabetes and prediabetes, Johns Hopkins scientists say the discovery could lead to a simple, routine test for detecting the subtle onset of the disease, before symptoms or complications occur and in time to reverse its course.

Pilot studies, published online April 22 in Diabetes, show the enzyme O-GlcNAcase is up to two to three times higher in people with diabetes and prediabetes than in those with no disease: "That's a big difference, especially in an enzyme that's as tightly regulated as this one is," says Gerald Hart, Ph.D., the DeLamar Professor and director of biological chemistry at the Johns Hopkins School of Medicine.

Building on their previous research, which showed how an abundant but difficult-to-detect sugar switch known as O-GlcNAc (pronounced oh-GLICK-nack) responded to nutrients and stress, the Hopkins team knew this small molecule was elevated in the red cells of patients with diabetes. "The question was whether the elevation happened in the earliest stages of diabetes and therefore might have value as a diagnostic tool," Hart said.

To find out, Kyoungsook Park, a graduate student of biological chemistry working in Hart's lab, focused on levels of O-GlcNAcase, an enzyme that removes O-GlcNAc in red cells. O-GlcNAc modifies many of the cell's proteins to control their functions in response to nutrients and stress. Nutrients, such as glucose and lipids, increase the extent of O-GlcNAc modification of proteins affecting their activities. When the extent of O-GlcNAc attached to proteins becomes too high, as occurs in diabetes, it is harmful to the cell.

First, Park purified human red blood cells by depleting them of their main constituent, hemoglobin. The samples had been collected by two sources -- the National Institute of Diabetes, Digestive and Kidney Diseases, or NIDDK, and Johns Hopkins Diabetes Center in collaboration with Christopher D. Saudek, M.D. -- and characterized as normal (36 samples), prediabetes (13 samples) and type 2 diabetes (53 samples) according to traditional tests that require patient fasting. Defined as normal hemoglobin A1c with impaired fasting glucose, prediabetes is an intermediate state of altered glucose metabolism with a heightened risk of developing type 2 diabetes and other associated complications.

Then, she measured and compared the amount of the enzyme protein within the red cells associated with the sugar molecule, O-GlcNAc.

"When I checked the enzyme levels and saw how dramatically different they were between the prediabetic cells and the controls, I thought I did something wrong," Park says. "I repeated the test five times until I could believe it myself."

Hart speculates that in diabetes and prediabetes, it's not a good thing for the increased amount of sugar to be attached to proteins, so the cell is responding by elevating the enzyme that gets rid of it.

"This is an example of how basic research is directly affecting a serious disease," Hart says, adding that his team's pilot studies encourage further investigation of a method that potentially could fill the void that currently exists for an easy, accurate routine test for prediabetes. "Only a much larger clinical trial will determine if, by measuring O-GlcNAcase, we can accurately diagnose prediabetes."

In addition to Park and Hart, Chistopher D. Saudek, also of Johns Hopkins University School of Medicine, is an author of the paper.

Funding was provided by the NIH NIDDK.


Story Source:

The above story is based on materials provided by Johns Hopkins Medical Institutions. Note: Materials may be edited for content and length.


Cite This Page:

Johns Hopkins Medical Institutions. "Sweet way to detect prediabetes." ScienceDaily. ScienceDaily, 9 July 2010. <www.sciencedaily.com/releases/2010/07/100708171349.htm>.
Johns Hopkins Medical Institutions. (2010, July 9). Sweet way to detect prediabetes. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2010/07/100708171349.htm
Johns Hopkins Medical Institutions. "Sweet way to detect prediabetes." ScienceDaily. www.sciencedaily.com/releases/2010/07/100708171349.htm (accessed July 31, 2014).

Share This




More Health & Medicine News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Peace Corps Pulls Workers From W. Africa Over Ebola Fears

Peace Corps Pulls Workers From W. Africa Over Ebola Fears

Newsy (July 30, 2014) The Peace Corps is one of several U.S.-based organizations to pull workers out of West Africa because of the Ebola outbreak. Video provided by Newsy
Powered by NewsLook.com
Weather Kills 2K A Year, But Storms Aren't The Main Offender

Weather Kills 2K A Year, But Storms Aren't The Main Offender

Newsy (July 30, 2014) Health officials say 2,000 deaths occur each year in the U.S. due to weather, but it's excessive heat and cold that claim the most lives. Video provided by Newsy
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

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