Anbuselvam C, Vijayavel K, Balasubramanian M P
Department of Pharmacology and Environmental Toxicology, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai 600 113, Tamil Nadu, India.
Chem Biol Interact. 2007 Jul 20;168(3):229-36. doi: 10.1016/j.cbi.2007.04.007. Epub 2007 Apr 22.
Reactive oxygen species (ROS) directly or indirectly involves in multistage process of carcinogenesis. Antioxidant activity of methanolic extract of Operculina turpethum stems (MEOT) on 7,12 dimethylbenz(a)anthracene (DMBA) induced breast cancer was investigated in female Sprague-Dawley rats. Changes in the levels of lipid peroxidation and antioxidants system was evaluated in addition to tumour development. Twenty four female rats were divided into four groups: control, DMBA, DMBA+MEOT and MEOT. In the DMBA group, rats were intragastrically administered with 20 mg of DMBA using corn oil as vehicle. Animals of DMBA+MEOT group received a single dose of 20 mg of DMBA dissolved in corn oil intragastrically followed by O. turpethum extract (100 mg/kg body weight), while MEOT group received O. turpethum extract (100 mg/kg body weight) intragastrically daily for a period of 45 days. After the experimental period of 45 days, oxidative stress parameters were assessed in serum, liver and breast of both control and experimental groups. In addition to this, tumour weight of breast was also assessed. A significant increase in lipid peroxidation levels were observed in the tested samples of cancer induced rats while the activities of enzymic antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and non-enzymic antioxidants like glutathione (GSH), ascorbic acid (Vitamin C) and alpha-tocopherol (Vitamin E) were decreased in cancer-bearing animals when compared to control animals. A significant (P<0.05) increase in the tumour weight was observed in the breast of DMBA group and the breast tumour weight decreased significantly (P<0.05) in the DMBA+MEOT groups. Oral administration of MEOT remarkably reduced the lipid peroxidation activity and increased the antioxidants level in drug treated animals and decreased the tumour weight significantly (P<0.05). This result suggests that MEOT shows antioxidant activity and play a protective role against DMBA induced breast cancer.
活性氧（ROS）直接或间接参与癌症发生的多阶段过程。在雌性斯普拉格-道利大鼠中研究了盒果藤茎甲醇提取物（MEOT）对7,12-二甲基苯并(a)蒽（DMBA）诱导的乳腺癌的抗氧化活性。除了肿瘤发展情况外，还评估了脂质过氧化水平和抗氧化系统的变化。将24只雌性大鼠分为四组：对照组、DMBA组、DMBA+MEOT组和MEOT组。在DMBA组中，大鼠以玉米油为载体经胃内给予20 mg DMBA。DMBA+MEOT组的动物先经胃内给予溶解于玉米油中的单剂量20 mg DMBA，随后给予盒果藤提取物（100 mg/kg体重），而MEOT组每天经胃内给予盒果藤提取物（100 mg/kg体重），持续45天。在45天的实验期后，评估对照组和实验组大鼠血清、肝脏和乳腺中的氧化应激参数。除此之外，还评估了乳腺肿瘤重量。在诱导癌症的大鼠测试样本中观察到脂质过氧化水平显著升高，而与对照动物相比，荷瘤动物体内超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx）等酶促抗氧化剂以及谷胱甘肽（GSH）、抗坏血酸（维生素C）和α-生育酚（维生素E）等非酶促抗氧化剂的活性降低。在DMBA组的乳腺中观察到肿瘤重量显著（P<0.05）增加，而在DMBA+MEOT组中乳腺肿瘤重量显著（P<0.05）降低。口服MEOT可显著降低药物治疗动物的脂质过氧化活性，提高抗氧化剂水平，并显著（P<0.05）降低肿瘤重量。该结果表明，MEOT具有抗氧化活性，并对DMBA诱导的乳腺癌起到保护作用。
