Featured Research

from universities, journals, and other organizations

Hepatitis C Virus May Need Enzyme's Help To Cause Liver Disease

Date:
July 11, 2008
Source:
University of Pittsburgh Schools of the Health Sciences
Summary:
A key enzyme may explain how hepatitis C infection leads to serious liver diseases. A new shows that fatty acid synthase is highly elevated in human liver cells exposed to the hepatitis C virus, suggesting that testing enzyme levels could help predict more serious, long-lasting health consequences from hepatitis C.

A key enzyme may explain how hepatitis C infection causes fatty liver -- a buildup of excess fat in the liver, which can lead to life-threatening diseases such as cirrhosis and liver cancer, report University of Pittsburgh Graduate School of Public Health and School of Medicine researchers.

The study shows that an enzyme known to play a major role in lipid production, fatty acid synthase (FAS), was highly elevated in human liver cells exposed to the hepatitis C virus. While preliminary, the research suggests that testing for elevated levels of FAS could help determine which patients with hepatitis C virus may go on to develop more serious, long-lasting health consequences brought on by fatty liver.

Nearly 200 million people worldwide are infected by hepatitis C, including 4 million Americans. Seventy percent of people with hepatitis C develop chronic liver disease, and the infection is the leading reason for liver transplantation in the United States.

Unlike hepatitis A and B, there is no vaccine to prevent hepatitis C infection. Since hepatitis C typically has no symptoms, many people do not know they have the infection until they develop signs of liver failure or fatty liver, sometimes decades after infection. The virus replicates and mutates quickly, helping it to evade discovery and attack by the immune system and allowing it to slowly wreak damage on the liver.

"Our study has provided new insight into how hepatitis C causes fatty liver. This has important implications for future studies and efforts to understand how the virus causes an increase in fatty acid levels that can lead to serious liver conditions," said Tianyi Wang, Ph.D., assistant professor, Department of Infectious Diseases and Microbiology, University of Pittsburgh Graduate School of Public Health, and the study's lead author.

To identify possible proteins in the hepatitis C virus linked to an increase in fatty acids, Dr. Wang worked with Thomas Conrads, Ph.D., co-director of clinical proteomics at the University of Pittsburgh Cancer Institute, and colleagues on a mass spectrometry-based proteomics approach in which they measured protein expression from liver cell cultures exposed to the hepatitis C virus. The approach sorted proteins based on their weight and electrical charge, looking for divergent patterns linked to the virus. Of the 175 proteins they identified, only FAS was highly elevated in cell cultures. Furthermore, when they blocked the expression of FAS, they noted a three to four times decrease in the level of the virus, indicating that FAS is directly linked to the virus's expression.

"Viruses are very complex, so it is challenging to determine what proteins may be at play in their survival and growth," said Dr. Wang. "The proteomic approach we used revealed many proteins linked to hepatitis C that may be worthy of further study, but FAS appears to be the protein most strongly associated with the production of fatty acids that can cause liver disease."

"Our next step in this research is to see how high the level of FAS is in tissue samples from hepatitis C patients and determine whether elevated FAS levels directly result in overproduction of fat in livers. If we learn that FAS is highly present in tissue, testing for it may be a way to predict those at risk for liver disease."

The study was published in the July 9 online issue of Hepatology. In addition to Drs. Wang and Conrads, other authors include Wei Yang, Ph.D., Sara Chadwick, B.S., and Shufeng Liu, Ph.D., University of Pittsburgh Graduate School of Public Health; Brian Hood, Ph.D., University of Pittsburgh Cancer Institute; Simon Watkins, Ph.D., University of Pittsburgh School of Medicine; and Guangxiang Luo, Ph.D., University of Kentucky College of Medicine.

The research was supported by a grant from the National Institutes of Health and University of Pittsburgh Central Research Development Funds.


Story Source:

The above story is based on materials provided by University of Pittsburgh Schools of the Health Sciences. Note: Materials may be edited for content and length.


Cite This Page:

University of Pittsburgh Schools of the Health Sciences. "Hepatitis C Virus May Need Enzyme's Help To Cause Liver Disease." ScienceDaily. ScienceDaily, 11 July 2008. <www.sciencedaily.com/releases/2008/07/080709091717.htm>.
University of Pittsburgh Schools of the Health Sciences. (2008, July 11). Hepatitis C Virus May Need Enzyme's Help To Cause Liver Disease. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2008/07/080709091717.htm
University of Pittsburgh Schools of the Health Sciences. "Hepatitis C Virus May Need Enzyme's Help To Cause Liver Disease." ScienceDaily. www.sciencedaily.com/releases/2008/07/080709091717.htm (accessed July 23, 2014).

Share This




More Health & Medicine News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Courts Conflicted Over Healthcare Law

Courts Conflicted Over Healthcare Law

AP (July 22, 2014) Two federal appeals courts issued conflicting rulings Tuesday on the legality of the federally-run healthcare exchange that operates in 36 states. (July 22) Video provided by AP
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Scientists Find New Way To Make Human Platelets

Scientists Find New Way To Make Human Platelets

Newsy (July 22, 2014) Boston scientists have discovered a new way to create fully functioning human platelets using a bioreactor and human stem cells. Video provided by Newsy
Powered by NewsLook.com
Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

TheStreet (July 21, 2014) New research shows Gilead Science's drug Sovaldi helps in curing hepatitis C in those who suffer from HIV. In a medical study, the combination of Gilead's Hep C drug with anti-viral drug Ribavirin cured 76% of HIV-positive patients suffering from the most common hepatitis C strain. Hepatitis C and related complications have been a top cause of death in HIV-positive patients. Typical medication used to treat the disease, including interferon proteins, tended to react badly with HIV drugs. However, Sovaldi's %1,000-a-pill price tag could limit the number of patients able to access the treatment. TheStreet's Keris Lahiff reports from New York. Video provided by TheStreet
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