α-亚麻酸代谢
中文名称
通路描述
α-亚麻酸 (ALA, 18:3(n-3)) 是一种omega-3脂肪酸，因人类无法合成，故通过饮食获得。ALA在人类健康中具有重要作用。它通过一系列交替的脱饱和和延长反应转化为长链更不饱和的n-3脂肪酸。来自ALA的omega-3产物如二十碳五烯酸 (EPA) 和二十二碳六烯酸 (DHA) 可减轻炎症，并可能降低慢性疾病的风险，如心脏病和关节炎。所有脱饱和和延长步骤均发生在内质网 (ER) 中，除了最后一步需要转位至过氧化物酶体进行部分beta-氧化。α-亚麻酸途径涉及以下步骤：18:3(n-3)--> 18:4(n-3)-->20:4(n-3)-->20:5(n-3)-->22:5(n-3)-->24:5(n-3)-->24:6(n-3)-->22:6(n-3)。该过程中涉及两种脱饱和酶：delta-6脱饱和酶将18:3(n-3)转化为18:4(n-3)以及将24:5(n-3)转化为24:6(n-3)；delta-5脱饱和酶将20:4(n-3)转化为20:5(n-3)。
英文描述
alpha-linolenic acid (ALA) metabolism Alpha-linolenic acid (ALA, 18:3(n-3)) is an omega-3 fatty acid, supplied through diet as it cannot be synthesized by humans. ALA has an important role in human health. It is converted to long chain more unsaturated n-3 fatty acids by a series of alternating desaturation and elongation reactions. Omega-3 products of ALA such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) reduce inflammation and may help lower risk of chronic diseases, such as heart disease and arthritis. All the desaturation and elongation steps occur in the endoplasmic reticulum (ER) except for the final step which requires translocation to peroxisomes for partial beta-oxidation.
The alpha-linolenic acid pathway involves the following steps: 18:3(n-3)--> 18:4(n-3)-->20:4(n-3)-->20:5(n-3)-->22:5(n-3)-->24:5(n-3)-->24:6(n-3)-->22:6(n-3). Two desaturation enzymes are involved in this process: delta-6 desaturase that converts 18:3(n-3) to 18:4(n-3) and 24:5(n-3) to 24:6(n-3) respectively, delta-5 desaturase 20:4(n-3) to 20:5(n-3). (Sprecher 2002).
The alpha-linolenic acid pathway involves the following steps: 18:3(n-3)--> 18:4(n-3)-->20:4(n-3)-->20:5(n-3)-->22:5(n-3)-->24:5(n-3)-->24:6(n-3)-->22:6(n-3). Two desaturation enzymes are involved in this process: delta-6 desaturase that converts 18:3(n-3) to 18:4(n-3) and 24:5(n-3) to 24:6(n-3) respectively, delta-5 desaturase 20:4(n-3) to 20:5(n-3). (Sprecher 2002).
所含基因
12 个基因