Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, Gwanak-gu, Republic of Korea.
Exp Anim. 2010;59(5):595-604. doi: 10.1538/expanim.59.595.
Obesity is a condition of abnormal adipose tissue storage and recently it has been recognized as a major factor in metabolic syndrome. High-fat diet-induced obesity in the C57BL/6 mouse is an important animal model because of its similarities with human obesity. The aim of the present study was to estimate obesity, liver injury and steatohepatitis, and the distribution of inducible nitric oxide synthase (iNOS) in mice with high-fat diet induced obesity. Three-week-old male C57BL/6J mice were fed either a high-fat diet (D-60: 60 kcal% fat, or D-45: 45 kcal% fat) or a normal diet (D-10: 10 kcal% fat) for 15 weeks. Oral glucose tolerance tests and intraperitoneal glucose tolerance tests showed that the D-60 mice had severely impaired glucose tolerance. In serum chemistry values and histopathological lesions, the D-60 group showed severe steatohepatitis. A distinct positive signal for iNOS was detected by immunohistochemistry in the cytoplasm of hepatocytes around the central vein in the D-45 and D-60 groups. Serum insulin levels and insulin immunohistochemistry in the pancreas showed pancreatic injury and insulin resistance in the D-60 group. We observed the presence of more iNOS in the high-fat diet-induced obese mouse, which has characteristics of non-alcoholic steatohepatitis (NASH) and diabetes, and expect that these background pathological data will be useful in research on obesity, diabetes mellitus, and non-alcoholic fatty liver disease.
肥胖是一种异常脂肪组织储存的状况，最近它被认为是代谢综合征的一个主要因素。高脂肪饮食诱导的 C57BL/6 小鼠肥胖是一种重要的动物模型，因为它与人类肥胖有相似之处。本研究旨在评估高脂肪饮食诱导肥胖小鼠的肥胖、肝损伤和脂肪性肝炎，以及诱导型一氧化氮合酶（iNOS）的分布。将 3 周龄雄性 C57BL/6J 小鼠分别喂食高脂肪饮食（D-60：60%热量脂肪，或 D-45：45%热量脂肪）或正常饮食（D-10：10%热量脂肪）15 周。口服葡萄糖耐量试验和腹腔内葡萄糖耐量试验表明，D-60 组的葡萄糖耐量严重受损。在血清化学值和组织病理学病变中，D-60 组表现出严重的脂肪性肝炎。免疫组织化学显示，D-45 和 D-60 组中央静脉周围的肝细胞细胞质中 iNOS 呈明显阳性信号。血清胰岛素水平和胰腺胰岛素免疫组化显示，D-60 组存在胰腺损伤和胰岛素抵抗。我们观察到在高脂肪饮食诱导肥胖的小鼠中存在更多的 iNOS，其具有非酒精性脂肪性肝炎（NASH）和糖尿病的特征，我们期望这些背景病理数据将有助于肥胖、糖尿病和非酒精性脂肪肝疾病的研究。
