Lands Bill
Fellow, American Society for Nutrition, 6100 Westchester Park Drive, #1219, College Park, MD 20740, USA.
Prostaglandins Other Lipid Mediat. 2017 Nov;133:4-10. doi: 10.1016/j.prostaglandins.2017.05.002. Epub 2017 May 20.
A hyperbolic, saturable, competitive dynamic of ligand binding to metabolic enzymes and lipid mediator receptors gives non-linear dose-response interactions that need careful management when planning or interpreting nutrient-based interventions. Relatively indiscriminate metabolism during accumulation of HUFA from n-3 and n-6 nutrients allows the amounts of n-3 and n-6 nutrients to determine the HUFA balance accumulated in tissue phospholipids. However, when HUFA-based eicosanoid actions are more intense with n-6 than n-3 mediators, they cause healthy physiology to shift toward pathophysiology. The proportion of n-6 in tissue HUFA directly relates to the severity of conditions caused by excessive n-6 actions. In the absence of n-3 nutrients, dietary linoleate (18:2n-6) has a very narrow therapeutic window below 1 percent of food energy, and it is widened by n-3 nutrients. The predictable quantitative dynamics of competing n-3 and n-6 nutrients allows design of successful preventive nutrition protocols that confirm and extend the epidemiologically observed benefits of n-3 nutrients.
配体与代谢酶及脂质介质受体的结合呈现双曲线、饱和、竞争性动态，这会产生非线性剂量反应相互作用，在规划或解释基于营养素的干预措施时需要谨慎处理。从n-3和n-6营养素积累高度不饱和脂肪酸（HUFA）期间相对不加区分的代谢，使得n-3和n-6营养素的量能够决定组织磷脂中积累的HUFA平衡。然而，当基于HUFA的类二十烷酸作用在n-6介质中比在n-3介质中更强烈时，它们会使健康生理状态转向病理生理状态。组织HUFA中n-6的比例直接关系到由过量n-6作用引起的病症的严重程度。在缺乏n-3营养素的情况下，膳食亚油酸（18:2n-6）在低于食物能量1%时具有非常窄的治疗窗口，而n-3营养素会使其变宽。n-3和n-6营养素竞争的可预测定量动态，使得能够设计出成功的预防性营养方案，这些方案证实并扩展了流行病学观察到的n-3营养素的益处。
