Milk Thistle Interferes With Hepatitis C Replication
For centuries, the extract from the milk thistle plant has been used to improve liver function. This practice is widely recognized – especially by the millions of people living with chronic Hepatitis C – a viral infection that can cause progressive damage to the liver. Hundreds of studies have provided evidence that silymarin, milk thistle’s extract, is a potent liver cell protector. However, there have also been an abundance of conflicting reports regarding milk thistle’s ability to directly affect the Hepatitis C virus. Providing even more reason for those with Hepatitis C to take milk thistle, a new study tips the scales of doubt by showing that silymarin exerts multiple effects against the lifecycle of the Hepatitis C virus.
Two previous studies that have indicated silymarin’s usefulness against Hepatitis C include:
- The February 2008 issue of Hepatology looked at milk thistle use among 1,145 participants in the HALT-C study, sponsored by the National Institute of Diabetes and Digestive and Kidney Disease. Although milk thistle users in this study showed similar liver enzyme levels and Hepatitis C viral loads to non-users, those taking milk thistle showed fewer liver-related symptoms and an improved quality of life.
- The March 2010 issue of Gastroenterology published a French study where researchers evaluated a commercially available intravenous preparation of silibinin – the most active component of silymarin – in those with the Hepatitis C virus. The researchers agreed that silibinin inhibited Hepatitis C polymerase function – a result comparable to what the STAT-C (specifically targeted antiviral therapy for Hepatitis C) drugs can do – without their accompanying hazards.
The new study that further identifies milk thistle as an anti-Hepatitis C substance examined the antiviral properties and mechanisms of silymarin on cultured (grown in a lab) human liver cells infected with the virus. The study, funded in part by the National Center for Complementary and Alternative Medicine (NCCAM), was published in the June 2010 edition of the journal, Hepatology.
After growing human liver cells and infecting them with the Hepatitis C virus, the cells were exposed to either standard Hepatitis C drug treatment or a diluted dose of silymarin. The researchers then found the following:
- Silymarin prevented the entry and fusion of the Hepatitis C virus into the target liver cells.
- Silymarin inhibited the ability of the virus to produce RNA, thus interfering with a portion of the virus’ lifecycle.
- When measured against untreated cells, silymarin significantly decreased viral load (although to a lesser degree than treatment with interferon did).
- Silymarin prevented the cell-to-cell spread of the Hepatitis C virus.
Upon carefully taking all of the variables into account, the researchers concluded that silymarin’s antiviral action appears to include blocking the entry and transmission of the Hepatitis C virus, possibly by targeting the host cell.
Experts agree that more well-structured trials are needed to understand, quantify and verify silymarin’s effectiveness against the Hepatitis C virus. More ammunition is required to break down the wall of doubt surrounding this herb’s contribution to the Hepatitis C community. In the meantime, there is sufficient evidence confirming silymarin’s ability to protect liver cells and improve liver function – two properties that everyone with Hepatitis C could benefit from.
http://nccam.nih.gov/research/results/spotlight/061610.htm, Effects of Milk Thistle Extract on the Hepatitis C Virus Lifecycle, Retrieved August 13, 2010, National Institutes of Health National Center for Complementary and Alternative Medicine, 2010.
http://www.hcvadvocate.org/news/newsLetter/2010/advocate0210.html#2, Healthwise: Milk Thistle, Lucinda K. Porter, RN, Retrieved August 13, 2010, Hepatitis C Support Project, 2010.
http://www.ncbi.nlm.nih.gov/pubmed/19962982, Silibinin and related compounds are direct inhibitors of hepatitis C virus RNA-dependent RNA polymerase, Ahmed-Belkacem A, et al, Retrieved August 14, 2010, Gastroenterology, March 2010.
http://www.ncbi.nlm.nih.gov/pubmed/20512985, Multiple effects of silymarin on the hepatitis C virus lifecycle, Wagoner J, et al, Retrieved August 13, 2010, Hepatology, June 2010.
http://www.webmd.com/digestive-disorders/tc/milk-thistle-topic-overview?ecd=wnl_hep_071510, Milk Thistle – Topic Overview, Retrieved August 14, 2010, WebMD, LLC, 2010.