Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal;
Institute for Innovation, Capacity Building and Sustainability of Agri-food Production (Inov4Agro), UTAD, Vila Real, Portugal.
Anticancer Res. 2024 Nov;44(11):4843-4856. doi: 10.21873/anticanres.17310.
BACKGROUND/AIM: This study aimed to investigate the influence of Western diet on mammary cancer in Wistar female rats, focusing on systemic responses and tumor development.
Twenty-eight Wistar female rats were acclimatized and divided into four experimental groups (n=7 each): Western diet (WD), Western diet with N-methyl-N-nitrosourea (MNU) administration (WD+MNU), standard diet (CTR), and standard diet with MNU administration (CTR+MNU). MNU was administered intraperitoneally at 50 mg/kg at seven weeks of age to induce mammary cancer. The 20-week experiment involved monitoring animal weight, food and water intake. At the end of the study, rats were euthanized, and blood samples and organs were collected for hematological and plasma biochemical analysis, oxidative stress, and histo-pathological and immunobiological evaluations of the tumors.
No significant differences were found in body weight, composition, or organ weights, but the WD group showed reduced food and water intake and lower cholesterol levels. Leptin and adiponectin levels were higher in the WD+MNU group, suggestive of changes in appetite regulation. Histopathological analysis showed malignant tumors in both MNU-induced groups. However, WD groups had fewer tumors compared to the CTR+MNU group.
WD led to higher feed efficiency and increased visceral adipose tissue but decreased systemic cholesterol and triglyceride levels. While this diet resulted in lower tumor incidence, the volume and weight of the tumors were higher. Additionally, the WD decreased ERα and progesterone receptor immunoexpression, while Ki-67 immunoexpression was elevated.
背景/目的：本研究旨在探讨西方饮食对 Wistar 雌性大鼠乳腺癌的影响，重点关注全身反应和肿瘤发展。
将 28 只 Wistar 雌性大鼠适应环境后分为四组进行实验（每组 7 只）：西方饮食（WD）组、西方饮食+N-甲基-N-亚硝脲（MNU）处理组（WD+MNU）、标准饮食（CTR）组和标准饮食+MNU 处理组（CTR+MNU）。在 7 周龄时，通过腹腔内注射 50mg/kg 的 MNU 诱导乳腺癌。20 周的实验包括监测动物体重、食物和水的摄入。在研究结束时，处死大鼠，采集血液样本和器官，进行血液学和血浆生化分析、氧化应激以及肿瘤的组织病理学和免疫生物学评估。
体重、组成或器官重量无显著差异，但 WD 组的食物和水摄入量减少，胆固醇水平降低。WD+MNU 组的瘦素和脂联素水平较高，提示食欲调节发生变化。组织病理学分析显示，MNU 诱导的两组均有恶性肿瘤。然而，与 CTR+MNU 组相比，WD 组的肿瘤数量较少。
WD 导致更高的饲料效率和增加内脏脂肪组织，但降低了系统胆固醇和甘油三酯水平。虽然这种饮食降低了肿瘤的发生率，但肿瘤的体积和重量更高。此外，WD 降低了 ERα 和孕激素受体的免疫表达，而 Ki-67 的免疫表达升高。
