ESSENTIALITY OF DIETARY OMEGA 3 FATTY ACIDS IN PRIMATES

Omega-3脂肪酸是光感受器和 神经膜以及前列腺素等的前体 二十烷类化合物。我们之前对恒河猴的研究表明， 妊娠期和婴儿期低omega-3脂肪酸饮食导致 大脑和视网膜的水平降低，视网膜功能受损， 视觉敏锐度发育较慢和视觉注意力的变化。全 这些发现在人类婴儿中得到证实，并导致 婴儿配方奶粉中的omega-3脂肪酸。我们现在正在研究 不同膳食水平和来源对omega-3脂肪的影响 酸对免疫系统功能的影响。 我们比较了三组以低摄入量喂养的恒河猴 亚麻酸(18：3w3)，亚麻酸含量高，或补充 较长链的欧米茄-3脂肪酸，二十二碳六烯酸(DHA， 22：6w3)，在灵长类动物的乳汁中发现，但在目前的美国婴儿中没有 公式。对免疫系统功能进行了几周的评估 在动物的变化带来不可避免的压力之前和之后 住房间。中性粒细胞的数量和比例，总计 淋巴细胞、CD4+、CD8+和CD20+淋巴细胞亚群 通过差异细胞计数和流式细胞仪测定 对T淋巴细胞有丝分裂原植物血凝素(PHA)的反应是 通过三组人的血液样本进行测量。 在所有时间点上，喂食DHA的动物的 对PHA的反应比喂食低水平或高水平的 亚麻酸。此外，补充DHA的动物有一个 显著提高CD8+淋巴细胞的比例 (抑制性/细胞毒性T淋巴细胞)，以及较低的CD4+/CD8+比率， 而不是喂食高亚麻酸饮食的动物。所有节食组都表现出 免疫系统对这一举动的反应是变化，但他们没有 以不同的方式回应。我们探索了两者之间可能的关系 这些发现和疾病的发生率，特别是轻微的 在猕猴身上常见的胃肠道感染。 添加DHA的动物的发病率显著降低。 出生后前4个月发生胃肠道寄生虫感染。 这些结果表明，补充DHA可能会减少 炎症反应，从而改善某些疾病过程。 在喂食高水平omega-3的成年人中发现了这种影响 脂肪酸，但以前从未在婴儿中得到证实 目前正在考虑将DHA水平用于人类婴儿喂养。我们是 试图证实这一发现并探索其背后的原因 机械装置。

Omega-3 fatty acids are a major constituent of photoreceptor and neural membranes as well as precursors of prostaglandins and other eicosanoids. Our previous studies of rhesus monkeys demonstrated that diets low in omega-3 fatty acids during gestation and infancy led to reduced levels in the brain and retina, deficits in retinal function, slower visual acuity development and changes in visual attention. All of these findings were confirmed in human infants and led to increased omega-3 fatty acids in human infant formulas. We are now examining the effects of different dietary levels and sources of omega-3 fatty acids on immune system function. We compared three groups of rhesus monkeys raised on diets low in linolenic acid (18:3w3), high in linolenic acid, or supplemented with the longer-chain omega-3 fatty acid, docosahexaenoic acid (DHA, 22:6w3), which is found in primate milk but not in current US infant formulas. Immune system function was evaluated for several weeks before and after the unavoidable stress of a change in the animals' housing room. The number and proportion of neutrophils, total lymphocytes, and CD4+, CD8+ and CD20+ lymphocyte subsets were determined by differential cell counts and flow cytometry, and response to a T-lymphocyte mitogen, phytohemagglutinin (PHA), was measured in blood samples from the three groups. Over all timepoints, animals fed DHA had a significantly lower response to PHA than animals fed either low or high levels of linolenic acid. In addition, DHA-supplemented animals had a significantly higher proportion of CD8+ lymphocytes (suppressor/cytotoxic T-lymphocytes), and a lower CD4+/CD8+ ratio, than animals fed the high linolenic acid diet. All diet groups showed immune system changes in response to the move, but they did not respond differentially. We explored possible relationships between these findings and the incidence of illness, specifically minor gastrointestinal infections which are common in macaque monkeys. DHA-supplemented animals had a significantly lower incidence of gastrointestinal parasitic infections in the first 4 postnatal months. These results suggest that DHA supplementation may reduce inflammatory responses and thereby ameliorate some disease processes. Such effects have been found in adults fed high levels of omega-3 fatty acids, but have not been demonstrated previously in infants with the DHA levels now being considered for human infant feeding. We are attempting to confirm this finding and explore its underlying mechanisms.