44E-10 |
Conjugated linoleic acid (CLA) enhances cell apoptosis and inhibits cell proliferation in mice forestomach cancer model |
B. Q. CHEN1, Y. Zhu2, J. R. Liu1, Y. J. Kim3, Y. B. Xue1, and R. H. Liu3. (1) Dept. of Nutrition & Food Hygiene, Harbin Medical School, 199 E. Dazhi St., Harbin, 150001, China, (2) Institute of Nutrition & Food Hygiene, Chinese Academy of Preventive Medicine, Nan Wei Rd. 29, Beijing, 100050, China, (3) Dept. of Food Science, Cornell Univ., Ithaca, NY 14853-7201 Stomach cancer is one of the most common cancers in the world. Conjugated linoleic acid (CLA) has been shown to be a potent anticancer compound against a variety of cancers in animal models at relatively low levels. The objective of this study was designed to: 1) to determine the anti-cancer activity of CLA in mice stomach cancer model in vivo; 2) To determine the ability of CLA in the inhibition of cell proliferation in vivo; and 3) To determine if CLA affects apoptosis in vivo. Mice forestomach cancer was induced by gavage with 1 mg of benzo(a)pyrene for 4-weeks. 0.25 and 0.5% of CLA were given in the diet at the expense of dextrose. Complete necropsies were performed to determine the number, size and location of all forestomach tumors at 23 weeks after B(a)P administration. Cell proliferation in vivo was determined by bromodeoxyuridine (BrdU) labeling of the mice forestomach tissues. Apoptosis in the mice forestomach tissues was evaluated by fluorescein immunohistochemistry stain technique. When the animals fed with CLA for 7 weeks after B(a)P treatment for 4 weeks, the tumor incidence was significantly reduced (p<0.05). All mice in the B(a)P group had tumors. Tumor incidence was 69% in the 0.25% CLA group, and 60% in the 0.5% CLA group. There was no tumor incidence when B(a)P was not treated. CLA decreased BrdU labeling positive cells in mice forestomach epithelial cells and adenocytes at 11th week after mice were exposed to B(a)P from 2-9 week. CLA mixture elevated cell apoptosis in mice forestomach epithlial cells and adnocytes. This study showed CLA suppresses mice forestomach cancers by multiple mechanisms including inhibition of cell proliferation and elevation of cell apoptosis.
Session 44E, Nutraceuticals & Functional Foods
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