De blaadjes van blauwe bessen tegen hepatitis C*
Hepatitis C is een besmettelijke leverziekte als gevolg van een infectie door het
hepatitis C virus. Een infectie verloopt in het begin meestal symptoomloos. De infectie gaat in de meerderheid van de gevallen (70%) ongemerkt over in een chronische vorm en kan leiden tot leverschade (verlittekening), cirrose en zelfs leverkanker. Alhoewel er medicijnen zijn die de infectie kunnen verhelpen gebeurt dit slechts in de helft van de gevallen met flinke bijwerkingen. Sommige mensen krijgen pas 20 of 30 jaar na de besmetting klachten wanneer de lever al is aangetast. Uit een Japanse studie blijkt nu dat er mogelijk ook een natuurlijke oplossing kan zijn. De Japanse wetenschappers bestudeerden ongeveer 300 verschillende planten om hun effecten tegen een hepatitis C infectie. Een belangrijke kandidaat bleek het blad van een speciale blauwe bes, de Vaccinium virgatum te zijn. De in het blad aanwezige
proanthocyanen bleken het vermenigvuldigen van het virus te kunnen stoppen. De wetenschappers gaan nu onderzoeken waarom dat gebeurt.
Blueberry Leaves May Heal Hepatitis C
Hepatitis C is a contagious liver disease resulting from infection with the hepatitis C virus (HCV). Although the infection can be mild and not even produce noticeable symptoms, once established in the body chronic hepatitis C infection can progress to fibrosis (when the liver is scarred), cirrhosis, liver failure and even liver cancer. According to the Centers for Disease Control (CDC), the virus becomes persistent and chronically infects the liver in about 85 percent of those who contract HCV. Persistent infection is treated by western medicine with medications like peginterferon and ribavirin. And while it's true these drugs can wipe out the infection, they are only effective about half the time and they can produce very severe, debilitating side effects. So people who aren't cured by the drugs and who go on to develop cirrhosis or liver cancer may face death from the infection or require a liver transplant.
But now there's another avenue of hope for the 270 to 300 million people who are infected with hepatitis C worldwide. Research just published in the American Society of Biochemistry and Molecular Biology's Journal of Biochemistry (JVC) concludes a chemical found in blueberry leaves actually blocks the replication of the hepatitis C virus, shutting it down. This finding could open up a new and natural avenue for treating chronic HCV infections, according to scientist Hiroaki Kataoka and colleagues at the University of Miyazaki in Japan.
Because HCV is localized in the liver and can take two decades or more to develop into significant disease, Kataoka and colleagues reasoned a dietary supplement might help slow or stop disease progression over the years. They decided to screen around 300 different agricultural products for potential compounds that might be effective at suppressing HCV replication. The results? They uncovered a strong candidate for a natural HCV fighter -- the leaves of the rabbit-eye blueberry, a plant native to the southeastern US.
They purified the specific compound in the leaves that is active against HCV and an analysis showed it is a proanthocyandin (a polyphenol much like the beneficial natural chemicals found in grapes and wine). While large doses of proanthocyandin can be toxic, Kataoka and his research team found the plant's effective concentration against HCV was 100 times less than the toxic threshold. What's more, similar chemicals are found in many edible plants, so the scientists believe it should be safe as a dietary supplement. The researchers are now planning to study exactly how this chemical blocks replication of the hepatitis C virus.
Reference:
"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. (Oktober
2009)
