University Eye Clinic Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands.
School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.
PLoS One. 2021 May 28;16(5):e0252630. doi: 10.1371/journal.pone.0252630. eCollection 2021.
Recently, the level of growth differentiation factor 15 (GDF-15) in blood, was proposed as biomarker to detect mitochondrial dysfunction. In the current study, we evaluate this biomarker in open-angle glaucoma (OAG), as there is increasing evidence that mitochondrial dysfunction plays a role in the pathophysiology of this disease.
Plasma GDF-15 concentrations were measured with ELISA in 200 OAG patients and 61 age-matched controls (cataract without glaucoma). The OAG patient group consisted of high tension glaucoma (HTG; n = 162) and normal tension glaucoma (NTG; n = 38). Groups were compared using the Kruskal-Wallis nonparametric test with Dunn's multiple comparison post-hoc correction. GDF-15 concentration was corrected for confounders identified with forward linear regression models.
Before correcting for confounders, median plasma GDF-15 levels was significantly lower in the combined OAG group (p = 0.04), but not when analysing HTG and NTG patients separately. Forward linear regression analysis showed that age, gender, smoking and systemic hypertension were significant confounders affecting GDF-15 levels. After correction for these confounders, GDF-15 levels in OAG patients were no longer significantly different from controls. Subgroup analysis of the glaucoma patients did not show a correlation between disease severity and plasma GDF-15, but did reveal that for NTG patients, intake of dietary supplements, which potentially improve mitochondrial function, correlated with lower plasma GDF-15.
The present study suggests that plasma GDF-15 is not suited as biomarker of mitochondrial dysfunction in OAG patients.
最近，血液中生长分化因子 15（GDF-15）的水平被提出作为检测线粒体功能障碍的生物标志物。在目前的研究中，我们评估了这种生物标志物在开角型青光眼（OAG）中的作用，因为越来越多的证据表明线粒体功能障碍在这种疾病的病理生理学中起作用。
使用 ELISA 法测量 200 例 OAG 患者和 61 名年龄匹配的对照者（白内障伴无青光眼）的血浆 GDF-15 浓度。OAG 患者组包括高眼压青光眼（HTG；n = 162）和正常眼压青光眼（NTG；n = 38）。使用 Kruskal-Wallis 非参数检验和 Dunn 多重比较事后校正比较各组。使用向前线性回归模型校正混杂因素后，校正 GDF-15 浓度。
在未校正混杂因素之前，联合 OAG 组的血浆 GDF-15 水平显著降低（p = 0.04），但分别分析 HTG 和 NTG 患者时则不然。向前线性回归分析显示，年龄、性别、吸烟和系统性高血压是影响 GDF-15 水平的显著混杂因素。校正这些混杂因素后，OAG 患者的 GDF-15 水平与对照组不再有显著差异。青光眼患者的亚组分析显示，疾病严重程度与血浆 GDF-15 之间无相关性，但确实表明对于 NTG 患者，饮食补充剂的摄入（可能改善线粒体功能）与较低的血浆 GDF-15 相关。
本研究表明，血浆 GDF-15 不适合作为 OAG 患者线粒体功能障碍的生物标志物。
