Colostral and milk insulin-like growth factors and related substances: Mammary gland and neonatal (intestinal and systemic) targets
Colostral and milk insulin-like growth factors and related substances: Mammary gland and neonatal (intestinal and systemic) targets
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DOI：
10.1016/s0739-7240(02)00149-2
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发表时间：
2002-07-01
影响因子：
2.1
通讯作者：
Baumrucker, CR
中科院分区：
文献类型：
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作者：
Blum, JW;Baumrucker, CR
初乳和乳汁中激素和调节因子的鉴定导致了对它们在乳腺和新生儿组织发育和维持中的作用的深入研究。转基因小鼠中胰岛素样生长因子（IGFs）和胰岛素样生长因子结合蛋白（IGFBPs）对哺乳末期乳腺生物学的影响。在牛中，IGFBP-3是乳腺分泌物中的主要IGFBP。除了结合IGFs，IGFBP-3还结合乳铁蛋白（Lf）。分泌的IGFBP-3重新进入乳腺上皮细胞，并且在核定位序列的存在下，IGFBP-3和Lf进入细胞核。核IGFBP-3通过视黄酸-X-受体影响凋亡信号传导，而Lf通过未知机制影响凋亡事件。这种相互作用可能影响乳房发育和退化。此外，摄入的初乳生物活性因子可以在新生儿中发挥调节功能。胰岛素样生长因子和胰岛素的肠道受体受年龄和/或饮食的影响。喂养IGF-I没有影响，但初乳提取物具有小肠效应（刺激增殖和绒毛大小），表明几个因素，而不是一个单一的生物活性因子负责。新生儿代谢和内分泌的系统变化取决于初乳的成分、数量、喂养时间和持续时间。产后早期初乳。摄入不仅对免疫球蛋白的提供和吸收很重要。因此，在新生小牛中，出生后前24小时内缺乏初乳摄入导致免疫球蛋白G、β-胡萝卜素和维生素A水平低，持续数周，脂肪酸、必需氨基酸和谷氨酰胺/谷氨酸盐比值的血浆模式受到影响。在小牛口服胰岛素样生长因子-I没有和喂养初乳乳清提取物只有轻微的影响代谢和内分泌性状。因此，乳腺分泌物影响乳腺和新生儿组织的调节功能。(C)2002年爱思唯尔科技有限公司All rights reserved.
The identification of hormones and regulatory factors in colostrum and milk has led to intensive investigations on their roles in the development and maintenance of the mammary and neonatal tissues. Insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) in transgenic mice influence mammary biology gland towards the end of lactation. In the bovine, IGFBP-3 is the major IGFBP in mammary secretions. In addition to binding IGFs, IGFBP-3 also binds to lactoferrin (Lf). Secreted IGFBP-3 re-enters mammary epithelial cells and with, the presence of a nuclear localization sequence, IGFBP-3 and Lf enter the nucleus. Nuclear IGFBP-3 affects apoptotic signaling through the retinoic-x-receptors, while Lf affects apoptotic events through unknown mechanisms. Such interactions likely influence mammary development and involution. Furthermore, ingested colostral bioactive factors can exert regulatory functions in neonates. Intestinal receptors for IGFs and insulin are modified by age and/or diet. Feeding IGF-I had no effect, but colostrum extracts had small intestinal effects (stimulation of proliferation and villus size), suggesting that several factors, rather than one single bioactive factor were responsible. Systemic changes of metabolic and endocrine profiles in neonates depend on composition, amounts, time and duration of feeding colostrum. Early postnatal colostrum. intake is not only important for the provision and absorption of immunoglobulins. Thus, in neonatal calves the lack of colostrum intake during the first 24 h after birth results in a low immunoglobulin G, beta-carotene and Vitamin A status that persists for weeks and plasma patterns of fatty acids, essential amino acids and the glutamine/glutamate ratios are affected. In calves oral administration of IGF-I had no and feeding of colostrum whey extracts had only minor effects on metabolic and endocrine traits. Thus, mammary secretions influence regulatory functions of mammary and neonatal tissues. (C) 2002 Elsevier Science Inc. All rights reserved.