Chen Yung-Ju, Wallig Matthew A, Jeffery Elizabeth H
Departments of Food Science and Human Nutrition and.
Pathobiology, University of Illinois, Urbana, IL.
J Nutr. 2016 Mar;146(3):542-50. doi: 10.3945/jn.115.228148. Epub 2016 Feb 10.
The high-fat and high-sugar Westernized diet that is popular worldwide is associated with increased body fat accumulation, which has been related to the development of nonalcoholic fatty liver disease (NAFLD). Without treatment, NAFLD may progress to hepatocellular carcinoma (HCC), a cancer with a high mortality rate. The consumption of broccoli in the United States has greatly increased in the last 2 decades. Epidemiologic studies show that incorporating brassica vegetables into the daily diet lowers the risk of several cancers, although, to our knowledge, this is the first study to evaluate HCC prevention through dietary broccoli.
We aimed to determine the impact of dietary broccoli on hepatic lipid metabolism and the progression of NAFLD to HCC. Our hypothesis was that broccoli decreases both hepatic lipidosis and the development of HCC in a mouse model of Western diet-enhanced liver cancer.
Adult 5-wk-old male B6C3F1 mice received a control diet (AIN-93M) or a Western diet (high in lard and sucrose, 19% and 31%, wt:wt, respectively), with or without freeze-dried broccoli (10%, wt:wt). Starting the following week, mice were treated once per week with diethylnitrosamine (DEN; 45 mg/kg body weight intraperitoneally at ages 6, 7, 8, 10, 11, and 12 wk). Hepatic gene expression, lipidosis, and tumor outcomes were analyzed 6 mo later, when mice were 9 mo old.
Mice receiving broccoli exhibited lower hepatic triglycerides (P < 0.001) and NAFLD scores (P < 0.0001), decreased plasma alanine aminotransferase (P < 0.0001), suppressed activation of hepatic CD68(+) macrophages (P < 0.0001), and slowed initiation and progression of hepatic neoplasm. Hepatic Cd36 was downregulated by broccoli feeding (P = 0.006), whereas microsomal triglyceride transfer protein was upregulated (P = 0.045), supporting the finding that dietary broccoli decreased hepatic triglycerides.
Long-term consumption of whole broccoli countered both NAFLD development enhanced by a Western diet and hepatic tumorigenesis induced by DEN in male B6C3F1 mice.
在全球流行的高脂肪、高糖的西式饮食与体内脂肪堆积增加有关，而这与非酒精性脂肪性肝病（NAFLD）的发生相关。未经治疗的NAFLD可能会进展为肝细胞癌（HCC），这是一种死亡率很高的癌症。在过去20年中，美国西兰花的消费量大幅增加。流行病学研究表明，将十字花科蔬菜纳入日常饮食可降低多种癌症的风险，不过据我们所知，这是第一项评估通过食用西兰花预防HCC的研究。
我们旨在确定食用西兰花对肝脏脂质代谢以及NAFLD进展为HCC的影响。我们的假设是，在西式饮食增强型肝癌小鼠模型中，西兰花可减少肝脏脂肪变性和HCC的发生。
5周龄成年雄性B6C3F1小鼠接受对照饮食（AIN-93M）或西式饮食（分别富含19%和31%的猪油和蔗糖，重量比），添加或不添加冻干西兰花（10%，重量比）。从下周开始，小鼠每周一次腹腔注射二乙基亚硝胺（DEN；6、7、8、10、11和12周龄时剂量为45 mg/kg体重）。6个月后，即小鼠9月龄时，分析肝脏基因表达、脂肪变性和肿瘤情况。
食用西兰花的小鼠肝脏甘油三酯水平较低（P < 0.001），NAFLD评分较低（P < 0.0001），血浆丙氨酸转氨酶降低（P < 0.0001），肝脏CD68(+)巨噬细胞的激活受到抑制（P < 0.0001），肝脏肿瘤的起始和进展减缓。喂食西兰花可使肝脏Cd36下调（P = 0.006），而微粒体甘油三酯转移蛋白上调（P = 0.045），这支持了食用西兰花可降低肝脏甘油三酯的发现。
长期食用完整的西兰花可对抗西式饮食增强的雄性B6C3F1小鼠的NAFLD发展以及DEN诱导的肝脏肿瘤发生。
