School of Psychology, Liverpool John Moores University, Liverpool, UK.
Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA.
Int J Neurosci. 2021 Apr;131(4):357-361. doi: 10.1080/00207454.2020.1744596. Epub 2020 Mar 31.
Major depressive disorder (MDD) in late life is linked to increased risk of subsequent dementia, but it is still unclear exactly what pathophysiological mechanisms underpin this link. A potential mechanism related to elevated risk of dementia in MDD is increased levels of α-synuclein (α-Syn), a protein found in presynaptic neuronal terminals. In this study, we examined cerebrospinal fluid (CSF) levels of α-Syn in conjunction with biomarkers of neurodegeneration (amyloid-β 42, total and phospho tau) and synaptic dysfunction (neurogranin), and measures of memory ability, in 27 cognitively intact older individuals with MDD and 19 controls. Our results show that CSF α-Syn levels did not significantly differ across depressed and control participants, but α-Syn was directly associated with neurogranin levels, and indirectly linked to poorer memory ability. All in all, we found that α-Syn may be implicated in the association between late life MDD and synaptic dysfunction, although further research is needed to confirm these results.
老年期重度抑郁症（MDD）与随后痴呆的风险增加有关，但尚不清楚是什么病理生理机制导致了这种联系。与 MDD 中痴呆风险增加相关的一个潜在机制是α-突触核蛋白（α-Syn）水平升高，α-Syn 是一种存在于突触前神经元末梢的蛋白质。在这项研究中，我们检查了 27 名认知正常的老年 MDD 患者和 19 名对照者的脑脊液（CSF）α-Syn 水平以及神经退行性变生物标志物（淀粉样β 42、总 tau 和磷酸化 tau）和突触功能障碍（神经颗粒蛋白），以及记忆能力的测量。我们的结果表明，CSF α-Syn 水平在抑郁组和对照组参与者之间没有显著差异，但 α-Syn 与神经颗粒蛋白水平直接相关，并与较差的记忆能力间接相关。总之，我们发现α-Syn 可能与老年期 MDD 和突触功能障碍之间的关联有关，尽管需要进一步的研究来证实这些结果。
