Surai P F, Brillard J P, Speake B K, Blesbois E, Seigneurin F, Sparks N H
Department of Biochemistry and Nutrition, Scottish Agricultural College Auchincruive, Ayr, Scotland UK.
Theriogenology. 2000 Mar 15;53(5):1025-39. doi: 10.1016/S0093-691X(00)00249-1.
Recent studies on chicken semen have suggested that the lipid and fatty acid composition of spermatozoa may be important determinants of fertility. Phospholipid fatty acid composition, vitamin E content and in vitro susceptibility to lipid peroxidation of duck spermatozoa were investigated using GC-MS and HPLC based methods. The total phospholipid fraction of duck spermatozoa was characterized by high proportions of the n-6 polyunsaturated fatty acids arachidonic (20:4n-6), docosatetraenoic (22:4n-6) and docosapentaenoic (22:5n-6) acids but a substantial proportion of the n-3 fatty acid docosahexaenoic (22:6n-3) acid was also present. Palmitic (16:0) and stearic (18:0) fatty acids were the major saturates in sperm phospholipids. Among the phospholipid classes, phosphatidylserine (PS) had the highest degree of unsaturation due to very high proportions of 22:6n-3, 22:5n-6, 22:4n-6 and 20:4n-6, comprising together more than 75% of total fatty acids in this fraction. Phosphatidylethanolamine (PE) also contained high proportions of these four C(20-22) polyunsaturates, which together formed 60% of total fatty acids in this phospholipid. Spermatozoa and seminal plasma of duck semen were characterized by unexpectedly low content of vitamin E, being more than 4-fold lower than in chicken semen. In duck semen the major proportion of the vitamin E (>70%) was located in the spermatozoa. The very high proportion of 22:6n-3 in PS and PE fractions of duck sperm lipids and the comparatively low levels of vitamin E could predispose semen to lipid peroxidation. Nevertheless the in vitro susceptibilities to Fe2+-stimulated lipid peroxidation of duck and chicken spermatozoa were very similar. The results of the study suggest that increased superoxide dismutase and glutathione peroxidase activity and increased antioxidant activity of seminal plasma may compensate for the low levels of vitamin E to help protect the membranes of duck spermatozoa, which exhibit a high degree of unsaturation from oxidative stress.
近期关于鸡精液的研究表明，精子的脂质和脂肪酸组成可能是生育能力的重要决定因素。采用基于气相色谱-质谱联用（GC-MS）和高效液相色谱（HPLC）的方法，对鸭精子的磷脂脂肪酸组成、维生素E含量及体外脂质过氧化敏感性进行了研究。鸭精子的总磷脂部分具有以下特点：n-6多不饱和脂肪酸花生四烯酸（20:4n-6）、二十二碳四烯酸（22:4n-6）和二十二碳五烯酸（22:5n-6）比例较高，但也含有相当比例的n-3脂肪酸二十二碳六烯酸（22:6n-3）。棕榈酸（16:0）和硬脂酸（18:0）是精子磷脂中的主要饱和脂肪酸。在磷脂类别中，磷脂酰丝氨酸（PS）的不饱和度最高，因为其22:6n-3、22:5n-6、22:4n-6和20:4n-6的比例非常高，这四种脂肪酸在该部分总脂肪酸中所占比例超过75%。磷脂酰乙醇胺（PE）也含有高比例的这四种C（20 - 22）多不饱和脂肪酸，它们在这种磷脂的总脂肪酸中占60%。鸭精液的精子和精浆中维生素E含量出奇地低，比鸡精液中的含量低4倍多。在鸭精液中，大部分维生素E（>70%）存在于精子中。鸭精子脂质的PS和PE部分中22:6n-3的比例非常高，而维生素E水平相对较低，这可能使精液易发生脂质过氧化。然而，鸭和鸡精子对Fe2+刺激的脂质过氧化的体外敏感性非常相似。该研究结果表明，超氧化物歧化酶和谷胱甘肽过氧化物酶活性的增加以及精浆抗氧化活性的增强，可能弥补维生素E水平的不足，有助于保护具有高度不饱和度的鸭精子膜免受氧化应激。
