日本研究人员8日宣布，他们在蓝莓的叶子中发现一种化学物质，可以阻止丙肝病毒的复制，从而延缓或阻止疾病发作。这项研究有助于科学家研发新的丙肝疗法。
日本宫崎大学的研究人员在美国新一期《生物化学杂志》上报告说，潜伏在人体内的丙肝病毒有些需要20年甚至以上的时间才会发病，他们因此设想可能是某种食物补充剂延缓或阻止了疾病的发作。研究人员检查了近300种农产品，结果发现在蓝莓叶子中有一种名为原花青素的物质可以阻止丙肝病毒的复制，从而达到延缓或阻止疾病发作的目的。
过量的原花青素对人体有害，但研究人员表示，使用它对抗丙肝病毒的剂量是安全的。类似原花青素的物质在很多可食用植物中都能够找到，他们认为，原花青素可以作为一种对抗丙肝病毒的安全食物补充剂。
研究人员希望下一步能弄清楚原花青素阻止丙肝病毒复制的机制。（生物谷Bioon.com）
生物谷推荐原始出处：
J. Biol. Chem., Vol. 284, Issue 32, 21165-21176, August 7, 2009
Proanthocyanidin from Blueberry Leaves Suppresses Expression of Subgenomic Hepatitis C Virus RNA*
Masahiko Takeshita, Yo-ichi Ishida, Ena Akamatsu, Yusuke Ohmori?, Masayuki Sudoh?, Hirofumi Uto||, Hirohito Tsubouchi||, and Hiroaki Kataoka**1
From the From the Research Division, Minami Nippon Dairy Co-op Co., Ltd., Miyazaki 885-0073, , the Miyazaki Prefectural Industrial Support Foundation, Miyazaki 880-0303, , the ?Kamakura Research Laboratories, Chugai Pharmaceutical Co., Ltd., Kanagawa 247-8530, , the ||Department of Digestive Disease and Life-style Related Disease, Health Research Human and Environmental Sciences, Kagoshima University, Graduate School of Medicine and Dental Sciences, Kagoshima 890-8520, and , the **Section of Oncopathology and Regenerative Biology, Department of Pathology, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan
ABSTRACT
Hepatitis C virus (HCV) infection is a major cause of chronic liver disease such as chronic hepatitis, cirrhosis, and hepatocellular carcinoma. While searching for new natural anti-HCV agents in agricultural products, we found a potent inhibitor of HCV RNA expression in extracts of blueberry leaves when examined in an HCV subgenomic replicon cell culture system. This activity was observed in a methanol extract fraction of blueberry leaves and was purified by repeated fractionations in reversed-phase high-performance liquid chromatography. The final purified fraction showed a 63-fold increase in specific activity compared with the initial methanol extracts and was composed only of carbon, hydrogen, and oxygen. Liquid chromatography/mass-ion trap-time of flight analysis and butanol-HCl hydrolysis analysis of the purified fraction revealed that the blueberry leaf-derived inhibitor was proanthocyanidin. Furthermore, structural analysis using acid thiolysis indicated that the mean degree of polymerization of the purified proanthocyanidin was 7.7, consisting predominantly of epicatechin. Proanthocyanidin with a polymerization degree of 8 to 9 showed the greatest potency at inhibiting the expression of subgenomic HCV RNA. Purified proanthocyanidin showed dose-dependent inhibition of expression of the neomycin-resistant gene and the NS-3 protein gene in the HCV subgenome in replicon cells. While characterizing the mechanism by which proanthocyanidin inhibited HCV subgenome expression, we found that heterogeneous nuclear ribonucleoprotein A2/B1 showed affinity to blueberry leaf-derived proanthocyanidin and was indispensable for HCV subgenome expression in replicon cells. These data suggest that proanthocyanidin isolated from blueberry leaves may have potential usefulness as an anti-HCV compound by inhibiting viral replication.
