Department of Nephrology, The Royal Melbourne Hospital, Parkville, Australia.
Department of Medicine (RMH), University of Melbourne, Parkville, Australia.
Osteoporos Int. 2022 Aug;33(8):1783-1794. doi: 10.1007/s00198-022-06420-z. Epub 2022 May 16.
Calciprotein particles (CPP) are nanoscale mineralo-protein aggregates that help stabilize excess mineral in the circulation. We examined the relationship between CPP and bone mineral density in Fabry disease patients. We found an inverse correlation with total hip and femoral neck density, but none with lumbar spine.
Calciprotein particles (CPP) are colloidal mineral-protein complexes made up primarily of the circulating glycoprotein fetuin-A, calcium, and phosphate. They form in extracellular fluid and facilitate the stabilization, transport, and clearance of excess minerals from the circulation. While most are monomers, they also exist in larger primary (CPP-I) and secondary (CPP-II) form, both of which are reported to be raised in pathological states. This study sought to investigate CPP levels in the serum of patients with Fabry disease, an X-linked systemic lysosomal storage disorder that is associated with generalized inflammation and low bone mineral density (BMD).
We compared serum CPP-I and CPP-II levels in 59 patients with Fabry disease (37 female) with levels in an age-matched healthy adult cohort (n=28) and evaluated their association with BMD and biochemical data obtained from routine clinical review.
CPP-I and CPP-II levels were higher in male Fabry disease patients than female sufferers as well as their corresponding sex- and age-matched controls. CPP-II levels were inversely correlated with BMD at the total hip and femoral neck, but not the lumbar spine. Regression analyses revealed that these associations were independent of common determinants of BMD, but at the femoral neck, a significant association was only found in female patients.
Low hip BMD was associated with high CPP-II in patients with Fabry disease, but further work is needed to investigate the relevance of sex-related differences and to establish whether CPP measurement may aid assessment of bone disease in this setting.
钙磷蛋白颗粒（CPP）是由循环中的糖蛋白胎球蛋白 A、钙和磷酸盐组成的纳米级矿化蛋白聚集体。它们在细胞外液中形成，有助于稳定循环中过量的矿物质，并促进其转运和清除。虽然大多数 CPP 是单体，但它们也以较大的初级（CPP-I）和次级（CPP-II）形式存在，这两种形式在病理状态下均被报道升高。本研究旨在探讨 Fabry 病患者血清中 CPP 水平，Fabry 病是一种 X 连锁系统性溶酶体贮积病，与全身炎症和低骨密度（BMD）有关。
我们比较了 59 例 Fabry 病患者（37 名女性）和年龄匹配的健康成年人队列（n=28）的血清 CPP-I 和 CPP-II 水平，并评估了它们与 BMD 及常规临床评估获得的生化数据的相关性。
与女性 Fabry 病患者和相应的性别及年龄匹配对照组相比，男性 Fabry 病患者的 CPP-I 和 CPP-II 水平更高。CPP-II 水平与全髋和股骨颈的 BMD 呈负相关，但与腰椎无关。回归分析表明，这些相关性独立于 BMD 的常见决定因素，但在股骨颈，仅在女性患者中发现了显著的相关性。
低髋 BMD 与 Fabry 病患者的 CPP-II 水平升高相关，但需要进一步研究以探讨性别差异的相关性，并确定 CPP 测量是否有助于评估该人群中的骨病。
