Article Date: 10 Aug 2009 - 1:00 PDT

A chemical found in blueberry leaves has shown a strong effect in blocking the replication of the Hepatitis C virus, opening up a new avenue for treating chronic HCV infections, which affect 200 million people worldwide and can eventually lead to cirrhosis and liver cancer.

Among the areas of especially high Hepatitis C incidence is the Miyazaki prefecture of southern Japan, a trend that led Hiroaki Kataoka and colleagues at the University of Miyazaki and elsewhere in Japan on a search for better treatment options. Currently, there is no vaccine for HCV, and though a combination drug regimen can clear HCV infection, this treatment is only about 60% effective on average and poses risks of severe side effects.

Kataoka and colleagues believed that since HCV is localized in the liver and can take 20 years or more to develop into disease, a dietary supplement might help slow or stop disease progression. So they screened nearly 300 different agricultural products for potential compounds that suppress HCV replication and uncovered a strong candidate in the leaves of rabbit-eye blueberry (native to the southeastern US).

They purified the compound and identified it as proanthocyandin (a polyphenol similar to the beneficial chemicals found in grapes and wine). While proanthocyandin can be harmful, Kataoka and colleagues noted its effective concentration against HCV was 100 times less than the toxic threshold, and similar chemicals are found in many edible plants, suggesting it should be safe as a dietary supplement. In the meantime, the researchers now hope to explore the detailed mechanisms of how this chemical stops HCV replication.

From the Article: "Proanthocyanidin from Blueberry Leaves Suppresses Expression of Subgenomic Hepatitis C Virus RNA" by Masahiko Takeshita, Yo-ichi Ishida, Ena Akamatsu, Yusuke Ohmori, Masayuki Sudoh, Hirofumi Uto, Hirohito Tsubouchi, and Hiroaki Kataoka. Article link: http://www.jbc.org/cgi/content/full/284/32/21165

Source:
Nick Zagorski
American Society for Biochemistry and Molecular Biology

Blueberries, Asparagus and HCV
—C.D. Mazoff, PhD

Being a lover of blueberries and asparagus, the recent news articles about research done on blueberries and HCV and asparagus and liver toxicity not only got my interest but also perked up my appetite!

I’ll eat as many blueberries as I can when they are in season – in smoothies, with ice cream, on my morning granola or cornflakes, or whatever. I always knew that blueberries were good antioxidants, but I didn’t know that an extract from the leaves has been shown to be a powerful agent against HCV.

Findings published in a recent article in the Journal of Biological Chemistry, by Masahiko Takeshita et al. of the University of Miyazaki “suggest that proanthocyanidin isolated from blueberry leaves may have potential usefulness as an anti-HCV compound by inhibiting viral replication,” thus slowing or stopping disease progression.¹

The researchers screened nearly 300 different agricultural products for potential compounds that suppress HCV replication and found one in the leaves of blueberries. The researchers purified the compound and identified it as proanthocyanidin, a polyphenol similar to the beneficial chemicals found in grapes. Okay, I eat grapes too. Double yum.

Apparently the blueberry extract found to be most effective comes from a type of blueberry found in the South eastern USA: Rabbit eye blueberries (Vaccinium ashei).

A quick look on the internet showed me that Rabbit eye blueberries have been used in Food research for some time, but they are not the type used in blueberry extracts found in most health food stores – I checked. Hmmmm???

I did find this, however: “The common blueberry is an abundant source of several potent antioxidants, particularly Anthocyanin and related compounds. Clinical studies have shown that Anthocyanin neutralizes free radicals which are specific to age-related mental clarity and memory capacity. This particular family of antioxidants has also been proven effective in fighting the free radicals responsible for macular degeneration and other age-related eye disorders. A 2001 study at Tufts University rated blueberries as the most potent antioxidant of over 60 foods tested (Tufts University. Researching a Blueberry/Brain Power Connection. TuftsUniversity Health and Nutrition Letter, March 2001, Vol. 19. Number 1)”.²

Further investigation showed me that what blueberries do is lower cholesterol and other lipids, like triglycerides.

In fact research done at Saga University in Japan and published in 2008, showed that Vaccinium ashei had a startling efficacy in lowering hepatic lipids in rats.³

But nowhere could I find out where to get this extract, or how the extract is made, or if eating more blueberries would produce a similar effect. Bummer.

Asparagus
Just when I thought things couldn’t get better, along comes this news item about an article on Asparagus published in the Journal of Food Science saying that “an extract from asparagus may increase the function of enzymes in the liver and boost the metabolism of alcohol.” The researchers from Korea concluded that “the leaves of A. officinalis, which are normally discarded, have the potential for use in therapy designed to protect the liver from various harmful insults.” Sadly, again, no extract recipe.

Asparagus has long been used as an herbal medicine in Asia thanks to its anticancer effects. It also has antifungal, anti-inflammatory and diuretic properties, and its health properties probably result from its high levels of folate and potassium, and Vitamin C. Green asparagus contains approximately six times the levels of Vitamin C than citrus fruits. (http://food-facts.suite101.com)

Okay…but where do I find this stuff, and how do I make sure that it’s what it says it is, and how much do I take, and what are the side effects if any. All this worry is making me hungry.

I’ve got an idea. While I’m waiting for more information, I think I’ll make myself some grilled wild salmon with blueberry sauce, have lots of asparagus on the side, and worry about it tomorrow. Because the way it seems to me is that lowering serum lipids and boosting glucose tolerance is the best thing I can do for my liver in the meantime, and that I can control my health for now with my diet.

Notes:
¹“Proanthocyanidin from Blueberry Leaves Suppresses Expression of Subgenomic Hepatitis C Virus RNA,” J. Biol. Chem., Vol. 284, Issue 32, 21165-21176, August 7, 2009

²www.blueberryextract.com

³Effect of Vaccinium ashei reade Leaves on Lipid Metabolism in Otsuka Long-Evans Tokushima Fatty Rats. Koji NAGAO1, et al. Saga University. Bioscience, Biotechnology, and Biochemistry Vol. 72 (2008) , No. 6 pp.1619-1622.

http://www.hcvadvocate.org/news/newsLetter/2009/advocate0909.html#5