Department of Medicine, University of Auckland, Private Bag 92019, Auckland, New Zealand.
Biometals. 2010 Jun;23(3):425-30. doi: 10.1007/s10534-010-9320-6. Epub 2010 Mar 16.
Lactoferrin is a pleiotropic factor with potent antimicrobial and immunomodulatory activities. In recent years, studies have shown that lactoferrin also acts on the skeleton to promote bone growth. Lactoferrin stimulates the proliferation and differentiation of the bone forming cells, the osteoblasts, and acts as a survival factor for these cells. Lactoferrin also inhibits osteoclastogenesis, reducing the number of cells that can actively resorb bone, thus producing a greater overall increase in bone volume. In vivo, local injection of lactoferrin results in substantial increases in bone area, establishing lactoferrin as an effector molecule in the skeleton. Investigations of the mechanism of action of lactoferrin in bone cells showed that the mitogenic effect of lactoferrin in osteoblasts is mediated mainly through LRP1, a member of the low density lipoprotein receptor-related proteins. Lactoferrin induces activation of p42/44 MAPK signaling as well as PI3-kinase-dependent phosphorylation of Akt in osteoblasts. Differential gene expression studies indicated a possible role for the activation of IGF1, Ptgs2 and Nfatc1 in mediating the mitogenic activity of lactoferrin in osteoblasts. Lactoferrin is a positive regulator of bone with a possible physiological role in bone growth and healing. There is a growing interest in the potential use of lactoferrin for the improvement of bone health, and in a number of recent studies dietary lactoferrin supplementation improved bone mineral density and bone strength. Lactoferrin appears to be a promising candidate for the development of an anabolic therapeutic factor for osteoporosis.
乳铁蛋白是一种具有强大抗菌和免疫调节活性的多功能因子。近年来的研究表明，乳铁蛋白还作用于骨骼，促进骨骼生长。乳铁蛋白刺激成骨细胞（骨形成细胞）的增殖和分化，并作为这些细胞的存活因子。乳铁蛋白还抑制破骨细胞的形成，减少可积极吸收骨的细胞数量，从而使骨量总体上有更大的增加。在体内，乳铁蛋白的局部注射导致骨面积的显著增加，从而使乳铁蛋白成为骨骼中的效应分子。对乳铁蛋白在骨细胞中的作用机制的研究表明，乳铁蛋白对成骨细胞的有丝分裂作用主要是通过 LDL 受体相关蛋白家族的成员 LRP1 介导的。乳铁蛋白诱导成骨细胞中 p42/44 MAPK 信号的激活以及 PI3-激酶依赖性 Akt 的磷酸化。差异基因表达研究表明，IGF1、Ptgs2 和 Nfatc1 的激活可能在介导乳铁蛋白在成骨细胞中的有丝分裂活性中起作用。乳铁蛋白是骨骼的正调节剂，在骨骼生长和愈合中可能具有生理作用。人们对乳铁蛋白在改善骨骼健康方面的潜在用途越来越感兴趣，在最近的一些研究中，饮食中乳铁蛋白的补充提高了骨密度和骨强度。乳铁蛋白似乎是开发用于治疗骨质疏松症的合成代谢治疗因子的有希望的候选物。
