Pizato Nathalia, Bonatto Sandro, Piconcelli Maressa, de Souza Lauro M, Sassaki Guilherme L, Naliwaiko Katya, Nunes Everson A, Curi Rui, Calder Philip C, Fernandes Luiz Claudio
Department of Physiology, Federal University of Paraná, Paraná, Brazil.
Nutrition. 2006 Apr;22(4):425-32. doi: 10.1016/j.nut.2005.11.001. Epub 2006 Feb 10.
We investigated the effect of the dietary ratio of omega-6 to omega-3 polyunsaturated fatty acids (PUFAs) from postweaning until adulthood on T-lymphocyte proliferation, T-lymphocyte subpopulations (helper and cytotoxic), and production of cytotoxic mediators by macrophages in tumor-bearing rodents.
Weanling male Wistar rats received a normal low-fat (40 g/kg of diet) chow diet or a high-fat (300 g /kg) diet that included fish or sunflower oil or blends of fish and sunflower oils to yield omega-6:omega-3 PUFA ratios of approximately 6:1, 30:1, and 60:1 ad libitum. After 8 wk, 50% of rats in each group were inoculated with 1 mL of 2 x 10(7) Walker 256 cells. Fourteen days after tumor inoculation, animals were killed and lymphocytes and macrophages were obtained for study.
The diets richest in omega-6 PUFA resulted in higher proliferation of thymus, spleen, and gut-associated lymphocytes compared with the chow diet irrespective of tumor burden. In contrast, the fish oil diet resulted in lower proliferation of thymus and spleen lymphocytes compared with the chow diet. Diets rich in omega-6 PUFA decreased the proportion of CD8+ lymphocytes. In non-tumor-bearing and tumor-bearing rats, hydrogen peroxide production by macrophages was highest in rats that consumed diets high in omega-3 PUFAs. Superoxide and nitric oxide production were little affected by the dietary ratio of omega-6 to omega-3 PUFAs.
Dietary omega-6 and omega-3 PUFA contents alter immune function in non-tumor-bearing and tumor-bearing rats. The omega-3 PUFAs decreased T-cell proliferation but increased hydrogen peroxide production compared with omega-6 PUFAs. Decreased tumor growth and cachexia and increased survival previously reported for fish oil in Walker 256 tumor-bearing rats may be related to improved macrophage function rather than to improved T-cell function.
我们研究了从断奶到成年期饮食中ω-6与ω-3多不饱和脂肪酸（PUFA）的比例对荷瘤啮齿动物T淋巴细胞增殖、T淋巴细胞亚群（辅助性和细胞毒性）以及巨噬细胞产生细胞毒性介质的影响。
断乳雄性Wistar大鼠随意摄入正常低脂（40克/千克饮食）饲料或高脂（300克/千克）饲料，其中包括鱼油、葵花籽油或鱼油与葵花籽油的混合物，以产生约6:1、30:1和60:1的ω-6:ω-3 PUFA比例。8周后，每组50%的大鼠接种1毫升2×10⁷Walker 256细胞。肿瘤接种14天后，处死动物并获取淋巴细胞和巨噬细胞进行研究。
无论肿瘤负荷如何，富含ω-6 PUFA的饮食与普通饲料相比，导致胸腺、脾脏和肠道相关淋巴细胞的增殖更高。相比之下，与普通饲料相比，鱼油饮食导致胸腺和脾脏淋巴细胞的增殖更低。富含ω-6 PUFA的饮食降低了CD8⁺淋巴细胞的比例。在无瘤和荷瘤大鼠中，摄入富含ω-3 PUFA饮食大鼠的巨噬细胞产生的过氧化氢最高。超氧化物和一氧化氮的产生很少受到ω-6与ω-
