A new study by researchers at the Massachusetts General Hospital Center for Engineering in Medicine (MGH-CEM), have cited that a composite present in grapefruit and other citrus fruits may help fight chronic infection by hepatitis C virus (HCV).
The compound, which is a common flavonoid naringenin, aids in blocking the secretion of HCV from infected cells. The results of this study may have implications in finding potential therapy for the infection in human patients. A combination of naringenin and antiviral medication might allow patient to clear the virus from their livers.
The study led by Yaakov Nahmias, PhD, of the MGH-CEM, has reported that HCV is bound to very low-density lipoprotein (vLDL, a so-called 'bad' cholesterol) when it is secreted from liver cells and that the viral secretion required to pass infection to other cells may be blocked by the common flavonoid naringenin.
'By finding that HCV is secreted from infected cells by latching onto vLDL, we have identified a key pathway in the viral lifecycle. These results suggest that lipid-lowering drugs, as well as supplements, such as naringenin, may be combined with traditional antiviral therapies to reduce or even eliminate HCV from infected patients,' said Nahmias.
While HCV infects about 3 pct of the world population existing antiviral medications are effective in only half of infected patients, 70 percent of whom develop chronic infection that can lead to cirrhosis or liver cancer.
As the virus does not integrate its genetic material into the DNA of infected cells like HIV, it is possible to totally clear the virus if new cells were not being infected by secreted virus.
'Identifying the route by which HCV is released from cells introduces a new therapeutic target. That pathway's dependence on cholesterol metabolism could allow us to interfere with viral propagation to other cells and tissues, using tools already developed for atherosclerosis treatment.' Yarmush is the Helen Andrus Benedict Professor of Surgery and Bioengineering at Harvard Medical School (HMS),' said Martin Yarmush, MD, PhD, director of the MGH-CEM.
Grapefruit's bitter taste is due to the presence of the flavonoid naringin, which is metabolized into naringenin, an antioxidant previously reported to help lower cholesterol levels.
It has been indicated through significant research that HCV infects liver cells by, in essence, 'hitching a ride' onto the natural lipoprotein-cholesterol metabolic pathway.
Previous research has shown that naringenin can reduce secretion of vLDL from liver cells, thereby causing the researchers to examine whether the compound might also lower HCV secretion from infected cells.
However, their experiments confirmed that naringenin does reduce the secretion of HCV from infected cell lines and showed that the compound hinders the mechanism for secreting a specific lipoprotein that binds HCV.
'This work presents the possibility that non-toxic levels of a dietary supplement, such as naringenin, could effectively block HCV secretion. This approach might eventually be used to treat patients who do not respond to or cannot take traditional interferon-based treatment or be used in combination with other agents to boost success rates,' said Raymond Chung, MD, MGH director of Hepatology.