目的:脂质运载蛋白2(LCN2)是一种参与许多生理功能的脂肪因子,包括骨代谢.我们先前在机械卸载诱导的骨质疏松症的小鼠模型和卧床志愿者队列中证明了其含义。因此,我们旨在研究其与绝经后骨质疏松症的关系。
方法:我们测量了血清LCN2,并将其水平与DickkopfWNT信号通路抑制剂1(DKK1)相关联,抗酒石酸酸性磷酸酶5B(TRAcP5B),硬化蛋白,尿I型胶原N末端端肽(NTX),血清I型胶原C末端端肽(CTX),与健康受试者相比,在年轻(50-65岁)和老年(66-90岁)骨质疏松妇女队列中通过ELISA进行的甲状旁腺激素和维生素K。还包括男性健康和骨关节炎患者的队列。Sobel调解分析用于检验年龄之间的间接关联,LCN2和DKK1或NTX。
结果:与健康受试者相比,骨质疏松和骨关节炎患者的LCN2水平没有变化,并且与BMD无关。然而,血清LCN2与健康女性(R=0.44;P=0.003)和男性(R=0.5;P=0.001)的年龄以及DKK1(R=0.47;P=0.003)和尿NTX(R=0.34;P=0.04)的血清浓度相关。Sobel介导分析显示LCN2介导了年龄与DKK1之间的间接关系(P=0.02),但不是NTX,在健康的科目。
结论:综合来看,结果表明,在健康个体中,LCN2、DKK1与年龄之间存在迄今未知的关联,但不是绝经后骨质疏松的女性。
OBJECTIVE: Lipocalin 2 (LCN2) is an adipokine involved in many physiological functions, including bone metabolism. We previously demonstrated its implication in mouse models of mechanical unloading-induced osteoporosis and in a cohort of bed rest volunteers. We therefore aimed at studying its involvement in postmenopausal osteoporosis.
METHODS: We measured serum LCN2 and correlated its levels to Dickkopf WNT Signaling Pathway Inhibitor 1 (DKK1), Tartrate Resistant Acid Phosphatase 5B (TRAcP5B), sclerostin, urinary N-terminal telopeptide of type I collagen (NTX), serum C-terminal telopeptide of type I collagen (CTX), parathyroid hormone and vitamin K by ELISA performed in a cohort of younger (50-65 years) and older (66-90 years) osteoporotic women in comparison to healthy subjects. A cohort of male healthy and osteoarthritic patients was also included. Sobel mediation analysis was used to test indirect associations among age, LCN2 and DKK1 or NTX.
RESULTS: LCN2 levels were unchanged in osteoporotic and in osteoarthritis patients when compared to healthy subjects and did not correlate with BMD. However, serum LCN2 correlated with age in healthy women (R = 0.44; P = 0.003) and men (R = 0.5; P = 0.001) and serum concentrations of DKK1 (R = 0.47; P = 0.003) and urinary NTX (R = 0.34; P = 0.04). Sobel mediation analysis showed that LCN2 mediates an indirect relationship between age and DKK1 (P = 0.02), but not with NTX, in healthy subjects.
CONCLUSIONS: Taken together, the results suggest a hitherto unknown association between LCN2, DKK1 and age in healthy individuals, but not in postmenopausal osteoporotic women.