Could Nitric Oxide Play a Role in Hepatitis C Treatment?
A gaseous compound found in the body, nitric oxide (NO) holds a bit of irony for those with Hepatitis C. This substance can be toxic, but it also plays a number of important roles in preserving our health. Of special interest to individuals with chronic Hepatitis C, researchers from Egypt have found that higher blood concentrations of NO are associated with better responses to Hepatitis C therapy.
About Nitric Oxide
Nitric oxide is distinct from nitrous oxide (N2O – commonly used by dentists as an anesthetic) and nitrogen dioxide (NO2 a major air pollutant). Although these three nitrogen based compounds are different, nitric oxide quickly oxidizes in the air to nitrogen dioxide.
Denoted by the chemical formula NO, nitric oxide is an important signaling molecule in human physiology. Outside the human body, NO is an air pollutant that is produced by combustion. Nitric oxide is a free radical – a substance known to be toxic because of its ability to damage nearby cells. However, NO is a free radical that is specifically used by the immune system to defend against pathogens – like parasites, cancerous cells, viruses and bacteria. In addition, nitric oxide has a host of other valuable functions to the body. NO:
- relaxes blood vessels, thus reducing blood pressure
- regulates the binding and release of oxygen to hemoglobin, thus aiding the supply of oxygen to generate energy
- stimulates the production of new mitochondria, thus increasing a cell’s energy production capability
Due to its healthful characteristics, supplementing with nitric oxide is growing in popularity for a variety of health concerns.
Nitric Oxide and Hepatitis C Treatment
Due to its antiviral effects, one of the applications the medical community is finding for nitric oxide is in infectious diseases. As published in a December 2010 edition of the Journal of Gastrointestinal and Liver Diseases, Egyptian researchers sought to determine if nitric oxide levels in the blood could predict the outcome of Hepatitis C treatment.
For 56 people with chronic Hepatitis C genotype 4, the researchers tested nitric oxide levels before and during antiviral treatment with pegylated interferon and ribavirin. They found the following:
- Before Treatment – Nitric oxide levels were significantly higher in sustained responders (those who were successful in eliminating Hepatitis C) compared to relapsers (those who initially cleared the Hepatitis C virus but then the virus returned) and non-responders (those who were not successful in eliminating Hepatitis C).
- During Treatment – Again, nitric oxide levels were significantly higher in sustained responders compared to relapsers and non-responders.
The authors concluded that in people with chronic Hepatitis C genotype 4, nitric oxide levels appeared to be associated with the outcome of antiviral treatment. Furthermore, they proposed that a nitric oxide-based therapy could potentially improve the therapeutic outcome of Hepatitis C treatment.
Despite the pollution threat nitric oxide poses to the environment upon oxidation, its presence in the bloodstream seems to be a blessing in the battle against Hepatitis C. Even though the Egyptian NO study focused only on Hepatitis C genotype 4, their data could translate to the other genotypes. Either way, the results are encouraging and warrant more research into the role nitric oxide might have in the treatment of chronic Hepatitis C.
References:
http://biology.unm.edu/toolson/biotox/nitric_oxide.ppt, Toxic effects of Nitric Oxide, Martha Gutierrez, Malerie Mock, Retrieved January 2, 2011, University of New Mexico, 2011.
http://en.wikipedia.org/wiki/Nitric_oxide, Nitric Oxide, Retrieved January 2, 2011, Wikimedia Foundation, Inc., 2011.
http://www.cvphysiology.com/Blood%20Flow/BF011.htm, Nitric Oxide, Retrieved January 2, 2011, Richard E. Klabunde, PhD, 2011.
http://www.jgld.ro/2010/4/8.html, Nitric Oxide Levels and Sustained Virological Response to Pegylated-Interferon alpha2a plus Ribavirin in Chronic HCV Genotype 4 Hepatitis: a Prospective Study, Ibrahim, M, et al, Retrieved January 2, 2011, Journal of Gastrointestinal and Liver Diseases, December 2010.
http://www.medterms.com/script/main/art.asp?articlekey=22508, Definition of Nitric Oxide, Retrieved January 2, 2011, MedicineNet, Inc., 2011.
http://www.ncbi.nlm.nih.gov/pubmed/15979491, Role of nitric oxide (NO) in interferon-alpha therapy for hepatitis C, Hokari A, et al, Retrieved January 2, 2011, The Journal of Infection, July 2005.
http://www.ncbi.nlm.nih.gov/pubmed/21188329, Nitric oxide levels and sustained virological response to pegylated-interferon alpha2a plus ribavirin in chronic HCV genotype 4 hepatitis: A prospective study, Ibrahim M, et al, Retrieved January 2, 2011, Journal of Gastrointestinal and Liver Diseases, December 2010.