Possible role of fatty acids in milk as the regulator of the expression of cytosolic binding proteins for fatty acids and vitamin A through PPARalpha in developing rats.
Possible role of fatty acids in milk as the regulator of the expression of cytosolic binding proteins for fatty acids and vitamin A through PPARalpha in developing rats.
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DOI：
10.3177/jnsv.53.515
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发表时间：
2007-12
影响因子：
1.6
通讯作者：
K. Mochizuki;H. Mochizuki;H. Kawai;Y. Ogura;M. Shimada;S. Takase;T. Goda
中科院分区：
文献类型：
--
作者：
K. Mochizuki;H. Mochizuki;H. Kawai;Y. Ogura;M. Shimada;S. Takase;T. Goda
牛奶中的脂肪酸被认为在出生后小肠的肠成熟和基因表达中起重要作用。在这项研究中，我们确定了空肠的mRNA水平，在大鼠中，过氧化物酶体增殖物激活受体α（PPARalpha）和PPARdelta，这是脂肪酸的核受体。我们还测量了产后期间其靶基因的表达，即肝脏型脂肪酸结合蛋白（L-FABP）和细胞视黄醇结合蛋白II型（CRBPII）。PPARalpha、L-FABP和CRBPII的mRNA水平在哺乳期逐渐升高，然后在断奶期结束时急剧下降到较低水平，而PPARdelta的mRNA水平则没有变化。在17日龄的幼鼠，断奶到高脂肪饮食，表现出显着更高的mRNA水平的PPARalpha，L-FABP和CRBPII比那些断奶到低脂肪饮食。在连续四天的断奶期间口服给予PPARalpha配体WY 14，643导致PPARalpha、L-FABP和CRBPII基因的mRNA水平平行增加。此外，辛酸和油酸，这是牛奶中脂肪酸的主要成分，诱导空肠PPARalpha，L-FABP和CRBPII基因表达。我们的研究结果表明，牛奶中的脂肪酸可能发挥关键作用，在维持一个增强的L-FABP和CRBPII基因在小肠中的表达水平，大概是作为诱导剂的PPARalpha基因表达。
Fatty acids in milk are thought to play an important role in intestinal maturation and gene expression in the postnatal small intestine. In this study, we determined the jejunal mRNA levels, in rats, of peroxisome proliferator-activated receptor alpha (PPARalpha) and PPARdelta which are nuclear receptors for fatty acids. We also measured expression of their target genes during the postnatal period, namely liver type fatty acid-binding protein (L-FABP) and cellular retinol-binding protein, type II (CRBPII). The mRNA levels of PPARalpha, L-FABP and CRBPII, but not PPARdelta, gradually increased during the suckling period and then sharply declined to a low level at the end of the weaning period. Rat pups at 17 d of age, weaned to a high-fat diet, showed significantly greater mRNA levels of PPARalpha, L-FABP and CRBPII than those weaned to a low-fat diet. Oral administration of PPARalpha ligand, WY14,643 during four consecutive days of the weanling period caused a parallel increase in the mRNA levels of PPARalpha, L-FABP and CRBPII genes. Furthermore, caprylic acid and oleic acid, which are major components of fatty acids in milk, induced jejunal PPARalpha, L-FABP and CRBPII gene expression. Our results suggest that fatty acids in milk may play a pivotal role in maintaining an enhanced level of expression of L-FABP and CRBPII genes in the small intestine, presumably by acting as inducers of PPARalpha gene expression.