Sarotra Pooja, Sharma Gayatri, Kansal Shevali, Negi Anjana Kumari, Aggarwal Ritu, Sandhir Rajat, Agnihotri Navneet
Department of Biochemistry, Panjab University, Chandigarh, 160014, India.
Lipids. 2010 Sep;45(9):785-98. doi: 10.1007/s11745-010-3459-3. Epub 2010 Aug 25.
n-3 Polyunsaturated fatty acids (PUFA) have a chemopreventive effect while n-6 PUFA promote carcinogenesis. The effect of these essential fatty acids may be related to oxidative stress. Therefore, the study was designed to evaluate the effect of different ratios of fish oil (FO) and corn oil (CO) in the prevention of colon cancer. Male Wistar rats were divided into control, dimethylhydrazine dihydrochloride (DMH) treated, FO + CO (1:1) and FO + CO (2.5:1). All the groups, except the control received a weekly injection of DMH for 4 weeks. The animals were sacrificed either 48 h later (initiation phase) or kept for 16 weeks (post initiation phase). DMH treatment in the initiation phase animals showed mild to moderate inflammation, decreased ROS and TrxR activity, increased antioxidants, apoptosis and ACF multiplicity. The post initiation study showed severe inflammation with hyperplasia, increased ACF multiplicity and ROS levels, a decrease in antioxidants and apoptosis. The FO + CO (1:1) treated animals showed severe inflammation, a decrease in ROS, an increase in antioxidants and apoptosis in the initiation phase. FO + CO (1:1) in the post initiation phase and FO + CO (2.5:1) in the initiation showed mild inflammation, increased ROS, apoptosis and decreased antioxidants. There was a decrease in ACF multiplicity and ROS levels, increased antioxidants and apoptosis in the post initiation phase study. The present study suggests that FO has a dose- and time-dependent chemopreventive effect in colon cancer mediated through oxidative stress and apoptosis.
n-3多不饱和脂肪酸（PUFA）具有化学预防作用，而n-6多不饱和脂肪酸则促进癌症发生。这些必需脂肪酸的作用可能与氧化应激有关。因此，本研究旨在评估鱼油（FO）和玉米油（CO）不同比例组合在预防结肠癌方面的作用。将雄性Wistar大鼠分为对照组、二甲基肼二盐酸盐（DMH）处理组、FO + CO（1:1）组和FO + CO（2.5:1）组。除对照组外，所有组每周注射一次DMH，共注射4周。在注射后48小时（启动阶段）处死动物，或饲养16周（启动后阶段）。启动阶段经DMH处理的动物表现出轻度至中度炎症，活性氧（ROS）和硫氧还蛋白还原酶（TrxR）活性降低，抗氧化剂增加，细胞凋亡和异常隐窝灶（ACF）数量增多。启动后研究显示有严重炎症伴增生，ACF数量和ROS水平增加，抗氧化剂和细胞凋亡减少。在启动阶段，经FO + CO（1:1）处理的动物表现出严重炎症，ROS减少，抗氧化剂增加，细胞凋亡增加。在启动后阶段，FO + CO（1:1）组以及在启动阶段FO + CO（2.5:1）组表现出轻度炎症，ROS、细胞凋亡增加，抗氧化剂减少。在启动后阶段研究中，ACF数量和ROS水平降低，抗氧化剂和细胞凋亡增加。本研究表明，鱼油在结肠癌中具有剂量和时间依赖性的化学预防作用，其作用通过氧化应激和细胞凋亡介导。
