血清 IGF-1 降低与肝性骨营养不良相关,是皮质骨而非小梁骨骨量低的主要决定因素。

Reduced Serum IGF-1 Associated With Hepatic Osteodystrophy Is a Main Determinant of Low Cortical but Not Trabecular Bone Mass.

机构信息

David B. Kriser Dental Center, Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, USA.

Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.

出版信息

J Bone Miner Res. 2018 Jan;33(1):123-136. doi: 10.1002/jbmr.3290. Epub 2017 Nov 6.

Abstract

Hepatic osteodystrophy is multifactorial in its pathogenesis. Numerous studies have shown that impairments of the hepatic growth hormone/insulin-like growth factor-1 axis (GH/IGF-1) are common in patients with non-alcoholic fatty liver disease, chronic viral hepatitis, liver cirrhosis, and chronic cholestatic liver disease. Moreover, these conditions are also associated with low bone mineral density (BMD) and greater fracture risk, particularly in cortical bone sites. Hence, we addressed whether disruptions in the GH/IGF-1 axis were causally related to the low bone mass in states of chronic liver disease using a mouse model of liver-specific GH-receptor (GHR) gene deletion (Li-GHRKO). These mice exhibit chronic hepatic steatosis, local inflammation, and reduced BMD. We then employed a crossing strategy to restore liver production of IGF-1 via hepatic IGF-1 transgene (HIT). The resultant Li-GHRKO-HIT mouse model allowed us to dissect the roles of liver-derived IGF-1 in the pathogenesis of osteodystrophy during liver disease. We found that hepatic IGF-1 restored cortical bone acquisition, microarchitecture, and mechanical properties during growth in Li-GHRKO-HIT mice, which was maintained during aging. However, trabecular bone volume was not restored in the Li-GHRKO-HIT mice. We found increased bone resorption indices in vivo as well as increased basal reactive oxygen species and increased mitochondrial stress in osteoblast cultures from Li-GHRKO and the Li-GHRKO-HIT compared with control mice. Changes in systemic markers such as inflammatory cytokines, osteoprotegerin, osteopontin, parathyroid hormone, osteocalcin, or carboxy-terminal collagen cross-links could not fully account for the diminished trabecular bone in the Li-GHRKO-HIT mice. Thus, the reduced serum IGF-1 associated with hepatic osteodystrophy is a main determinant of low cortical but not trabecular bone mass. © 2017 American Society for Bone and Mineral Research.

摘要

肝性骨营养不良的发病机制是多因素的。许多研究表明,非酒精性脂肪性肝病、慢性病毒性肝炎、肝硬化和慢性胆汁淤积性肝病患者的肝生长激素/胰岛素样生长因子-1 轴 (GH/IGF-1) 受损较为常见。此外,这些情况还与低骨密度 (BMD) 和更高的骨折风险相关,尤其是在皮质骨部位。因此,我们使用肝特异性生长激素受体 (GHR) 基因缺失 (Li-GHRKO) 的小鼠模型来探讨 GH/IGF-1 轴的破坏是否与慢性肝病状态下的低骨量有关。这些小鼠表现为慢性肝脂肪变性、局部炎症和 BMD 降低。然后,我们采用交叉策略通过肝 IGF-1 转基因 (HIT) 恢复肝产生 IGF-1。由此产生的 Li-GHRKO-HIT 小鼠模型使我们能够在肝疾病期间剖析肝源性 IGF-1 在骨营养不良发病机制中的作用。我们发现,肝源性 IGF-1 在 Li-GHRKO-HIT 小鼠的生长过程中恢复了皮质骨的获得、微结构和力学性能,并在衰老过程中得以维持。然而,Li-GHRKO-HIT 小鼠的小梁骨体积并未恢复。我们发现,与对照小鼠相比,Li-GHRKO 和 Li-GHRKO-HIT 小鼠体内的骨吸收指数增加,成骨细胞培养物中的基础活性氧增加,线粒体应激增加。全身标志物(如炎症细胞因子、骨保护素、骨桥蛋白、甲状旁腺激素、骨钙素或羧基末端胶原交联)的变化不能完全解释 Li-GHRKO-HIT 小鼠小梁骨减少的原因。因此,与肝性骨营养不良相关的血清 IGF-1 减少是皮质骨而不是小梁骨减少的主要决定因素。© 2017 美国骨骼与矿物质研究协会。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索