Antequera Desireé, Sande Lucía, Mato Eliane García, Romualdi Deborah, Carrero Laura, Municio Cristina, Diz Pedro, Carro Eva
Neurobiology of Alzheimer's Disease Unit, Functional Unit for Research Into Chronic Diseases, Instituto de Salud Carlos III, Madrid, Spain.
Network Centre for Biomedical Research in Neurodegenerative Diseases (CIBERNED), ISCIII, Spain.
Brain Behav Immun Health. 2025 Apr 21;46:100999. doi: 10.1016/j.bbih.2025.100999. eCollection 2025 Jul.
Individuals with Down Syndrome (DS) have a high age-dependent risk of developing Alzheimer's disease (AD). In addition to genetic causes, this high risk involves dysregulated immune-inflammatory system. Low lactoferrin levels, one of the main antimicrobial proteins present in saliva, has been associated with AD. Here, we evaluated whether salivary lactoferrin levels change across the life span of individuals with DS. The study included 152 participants, 72 subjects with DS and 80 euploid individuals, and were divided into those under and over 45 years of age, accordingly with the age-dependent risk of AD. Median of salivary lactoferrin were higher among DS individual, in parallel to salivary total protein, but there were no differences in the ratio of lactoferrin to total protein in saliva between groups. Only DS individuals had higher median salivary lactoferrin levels in the age group under 45 years. Meanwhile non-significant differences were detected for the ratio salivary lactoferrin levels to total salivary protein between groups under 45 years, those levels were lower in DS subjects over 45 years old compared with the age-matched control group. Furthermore, the ratio of salivary lactoferrin levels to total protein in DS was associated with cognitive decline being lower in demented groups compared with mild and moderate cognitive impairment groups. In summary, this study indicates that salivary lactoferrin was dysregulated in DS, with significant lower ratio of salivary lactoferrin levels to total salivary proteins in individuals with DS over 45 years old, a population with a gradually increasing risk of AD.
唐氏综合征（DS）患者患阿尔茨海默病（AD）的风险随年龄增长而升高。除了遗传因素外，这种高风险还涉及免疫炎症系统失调。乳铁蛋白是唾液中主要的抗菌蛋白之一，其水平较低与AD有关。在此，我们评估了DS患者一生中唾液乳铁蛋白水平是否会发生变化。该研究纳入了152名参与者，其中72名DS患者和80名非DS个体，并根据AD的年龄依赖性风险将其分为45岁以下和45岁以上两组。DS个体的唾液乳铁蛋白中位数较高，与唾液总蛋白情况相似，但两组之间唾液中乳铁蛋白与总蛋白的比例没有差异。只有45岁以下年龄组的DS个体唾液乳铁蛋白中位数较高。同时，45岁以下两组之间唾液乳铁蛋白水平与唾液总蛋白的比例差异无统计学意义，45岁以上的DS患者该水平低于年龄匹配的对照组。此外，DS患者中唾液乳铁蛋白水平与总蛋白的比例与认知能力下降有关，痴呆组低于轻度和中度认知障碍组。总之，本研究表明DS患者唾液乳铁蛋白失调，45岁以上DS个体的唾液乳铁蛋白水平与唾液总蛋白的比例显著降低，而这一人群患AD的风险在逐渐增加。
