Lipomobilization in periparturient dairy cows influences the composition of plasma nonesterified fatty acids and leukocyte phospholipid fatty acids
Lipomobilization in periparturient dairy cows influences the composition of plasma nonesterified fatty acids and leukocyte phospholipid fatty acids
复制标题
DOI：
10.3168/jds.2009-2876
复制
发表时间：
2010-06-01
影响因子：
3.5
通讯作者：
Sordillo, L. M.
中科院分区：
文献类型：
--
作者：
Contreras, G. A.;O'Boyle, N. J.;Sordillo, L. M.
围产期的特征是代谢和免疫细胞功能的突然变化，使奶牛易于增加疾病的发病率。代谢变化包括能量平衡的改变，其导致脂质动员增加，从而导致血浆非酯化脂肪酸（NEFA）浓度升高。本研究的目的是确定脂质动员对血浆脂质组分和白细胞磷脂组成中脂肪酸谱的影响。分别于预产期前14 d、7 d、产犊时、产犊后7 d、14 d、30 d采集10头奶牛的血样。从血浆和外周血单核细胞中提取总脂质和脂质组分。通过测量血浆NEFA浓度来表征脂质动员的程度。血浆NEFA、血浆磷脂和白细胞磷脂的脂肪酸谱与血浆中总脂质的组成不同，其中亚油酸是最常见的脂肪酸。分娩前后和泌乳早期，血浆NEFA和磷脂组分中棕榈酸的比例显著增加，同时白细胞的磷脂脂肪酸谱也随之增加。相反，白细胞中的长链多不饱和脂肪酸的磷脂部分减少围产期期间，特别是在分娩后的第一个2周。这项研究表明，总血脂的组成并不一定反映围产期奶牛的NEFA和磷脂组分。这些发现是重要的，因为它是血浆磷脂部分，有助于膜磷脂的脂肪酸组成。NEFA磷脂组分中某些饱和脂肪酸的可用性增加可能有助于围产期白细胞功能的改变。
The periparturient period is characterized by sudden changes in metabolic and immune cell functions that predispose dairy cows to increased incidence of disease. Metabolic changes include alterations in the energy balance that lead to increased lipomobilization with consequent elevation of plasma nonesterified fatty acids (NEFA) concentrations. The objective of this study was to establish the influence of lipomobilization on fatty acid profiles within plasma lipid fractions and leukocyte phospholipid composition. Blood samples from 10 dairy cows were collected at 14 and 7 d before due date, at calving, and at 7, 14, and 30 d after calving. Total lipids and lipid fractions were extracted from plasma and peripheral blood mononuclear cells. The degree of lipomobilization was characterized by measurement of plasma NEFA concentrations. The fatty acid profile of plasma NEFA, plasma phospholipids, and leukocyte phospholipids differed from the composition of total lipids in plasma, where linoleic acid was the most common fatty acid. Around parturition and during early lactation, the proportion of palmitic acid significantly increased in the plasma NEFA and phospholipid fractions with a concomitant increase in the phospholipid fatty acid profile of leukocytes. In contrast, the phospholipid fraction of long-chain polyunsaturated fatty acids in leukocytes was diminished during the periparturient period, especially during the first 2 wk following parturition. This study showed that the composition of total plasma lipids does not necessarily reflect the NEFA and phospholipid fractions in periparturient dairy cows. These findings are significant because it is the plasma phospholipid fraction that contributes to fatty acid composition of membrane phospholipids. Increased availability of certain saturated fatty acids in the NEFA phospholipid fractions may contribute to altered leukocyte functions during the periparturient period.