Hashimoto Michio, Hossain Shahdat, Al Mamun Abdullah, Matsuzaki Kentaro, Arai Hiroyuki
a Department of Environmental Physiology , Shimane University Faculty of Medicine , Izumo , Japan.
b Department of Biochemistry and Molecular Biology , Jahangirnagar University , Dhaka , Bangladesh.
Crit Rev Biotechnol. 2017 Aug;37(5):579-597. doi: 10.1080/07388551.2016.1207153. Epub 2016 Jul 17.
Docosahexaenoic acid (DHA, C22:6, ω-3) is a highly polyunsaturated omega-3 fatty acid. It is concentrated in neuronal brain membranes, for which reason it is also referred to as a "brain food". DHA is essential for brain development and function. It plays an important role in improving antioxidant and cognitive activities of the brain. DHA deficiency occurs during aging and dementia, impairs memory and learning, and promotes age-related neurodegenerative diseases, including Alzheimer's disease (AD). For about two decades, we have reported that oral administration of DHA increases spatial memory acquisition, stimulates neurogenesis, and protects against and reverses memory impairment in amyloid β peptide-infused AD rat models by decreasing amyloidogenesis and protects against age-related cognitive decline in the elderly. These results demonstrate a robust link between DHA and cognitive health. Rodents that were fed a diet low in ω-3 polyunsaturated fatty acids, particularly those that were DHA-deficient, frequently suffered from anxiety, depression and memory impairment. Although the exact mechanisms of action of DHA in brain functions are still elusive, a host of mechanisms have been proposed. For example, DHA, which inherently has a characteristic three-dimensional structure, increases membrane fluidity, strengthens antioxidant activity and enhances the expression of several proteins that act as substrates for improving memory functions. It reduces the brain amyloid burden and inhibits in vitro fibrillation and amyloid-induced neurotoxicity in cell-culture model. In this review, we discuss how DHA acts as a molecule with diverse functions.
二十二碳六烯酸（DHA，C22:6，ω-3）是一种高度多不饱和的ω-3脂肪酸。它集中在神经元细胞膜中，因此也被称为“脑食物”。DHA对大脑发育和功能至关重要。它在改善大脑的抗氧化和认知活动方面发挥着重要作用。DHA缺乏在衰老和痴呆过程中出现，损害记忆和学习能力，并促进包括阿尔茨海默病（AD）在内的与年龄相关的神经退行性疾病。大约二十年来，我们报告称，口服DHA可增加空间记忆获取，刺激神经发生，并通过减少淀粉样蛋白生成来预防和逆转淀粉样β肽注入的AD大鼠模型中的记忆损伤，并预防老年人与年龄相关的认知衰退。这些结果证明了DHA与认知健康之间的紧密联系。喂食低ω-3多不饱和脂肪酸饮食的啮齿动物，尤其是那些缺乏DHA的动物，经常患有焦虑、抑郁和记忆损伤。尽管DHA在脑功能中的具体作用机制仍然难以捉摸，但已经提出了许多机制。例如，DHA本身具有独特的三维结构，可增加膜流动性，增强抗氧化活性，并增强几种作为改善记忆功能底物的蛋白质的表达。它可减轻大脑淀粉样蛋白负担，并在细胞培养模型中抑制体外纤维化和淀粉样蛋白诱导的神经毒性。在这篇综述中，我们讨论了DHA如何作为一种具有多种功能的分子发挥作用。
