Department of Pharmacy, Kochi Medical School, Nankoku, Kochi, Japan.
J Pharm Pharmacol. 2010 Feb;62(2):241-6. doi: 10.1211/jpp.62.02.0012.
Non-alcoholic steatohepatitis is associated with the deposition of lipid droplets in the liver, and is characterised histologically by the infiltration of inflammatory cells, hepatocellular degeneration and liver fibrosis. Oxidative stress may play an important role in the onset and deterioration of non-alcoholic steatohepatitis. We previously reported that an Eriobotrya japonica seed extract, extracted in 70% ethanol, exhibited antioxidant actions in vitro and in vivo. In this study, we examined the effect of this extract in a rat model of non-alcoholic steatohepatitis.
The seed extract was given in the drinking water to fats being fed a methionine-choline-deficient diet for 15 weeks.
Increases in alanine aminotransferase and aspartate aminotransferase levels were significantly inhibited in rats fed the seed extract compared with the group on the diet alone. Formation of fatty droplets in the liver was also inhibited. Antioxidant enzyme activity in liver tissue was higher than in the diet-only group and lipid peroxidation was reduced compared with rats that also received the extract. Expression of 8-hydroxy-2'-deoxyguanosine and 4-hydroxy-2-nonenal was lower in the rats given the seed extract than in the diet-only group. In the former, liver tissue levels of transforming growth factor-beta and collagen were also decreased.
Thus, the E. japonica seed extract inhibited fatty liver, inflammation and fibrosis, suggesting its usefulness in the treatment of non-alcoholic steatohepatitis.
非酒精性脂肪性肝炎与肝内脂质滴沉积有关,其组织学特征为炎症细胞浸润、肝细胞变性和肝纤维化。氧化应激可能在非酒精性脂肪性肝炎的发病和恶化中起重要作用。我们之前报道过,70%乙醇提取的枇杷种子提取物具有体内外抗氧化作用。在本研究中,我们在非酒精性脂肪性肝炎大鼠模型中研究了该提取物的作用。
将种子提取物添加到饮用水中,给予脂肪饮食喂养的大鼠 15 周,该脂肪饮食中缺乏蛋氨酸和胆碱。
与仅喂食饮食的大鼠相比,喂食种子提取物的大鼠丙氨酸氨基转移酶和天冬氨酸氨基转移酶水平升高明显受到抑制。肝内脂肪滴的形成也受到抑制。与同时接受提取物的大鼠相比,肝组织中的抗氧化酶活性更高,脂质过氧化减少。给予种子提取物的大鼠 8-羟基-2'-脱氧鸟苷和 4-羟基-2-壬烯醛的表达低于仅喂食饮食的大鼠。前者肝组织转化生长因子-β和胶原的水平也降低。
因此,枇杷种子提取物抑制脂肪肝、炎症和纤维化,提示其在治疗非酒精性脂肪性肝炎方面的有用性。