Section of Gerontology and Geriatrics, Department of Medicine, Institute of Gerontology and Geriatrics, University of Perugia, Piazzale Gambuli 1, 06132, Perugia, Italy.
Section of Nutritional Sciences, University of Milan, Milan, Italy.
Eur J Nutr. 2020 Feb;59(1):119-126. doi: 10.1007/s00394-019-01892-y. Epub 2019 Jan 16.
Advancing age represents the strongest risk factor for Alzheimer's disease (AD), and the identification of biomarkers able to define what characterizes physiological aging from AD may represent a potential starting point for novel preventive strategies. Among these biomarkers, telomeres seem to be a promising target. Interestingly, high intake of carotenoid-rich food may play a role in protecting telomeres by oxidative stress reduction. Accordingly, low plasma β-carotene concentrations have been found in AD subjects when compared with cognitively healthy subjects. In this study, we aim at investigating the hypothesis that low β-carotene might be associated with markers of accelerated cellular aging, including leucocyte telomere length (LTL) and peripheral mononuclear cell (PBMC) telomerase activity in a cohort of old age subjects.
The study was conducted in 68 old age subjects, 37 AD, and 31 age-matched healthy controls. In all subjects, β-carotene plasma level, LTL and peripheral telomerase activity were measured.
In all populations, β-carotene significantly and positively (r = 0.320, p = 0.008) correlated with telomerase activity, independent of gender. A model having telomerase activity levels as the dependent variable, and age, gender, smoking habit, and β-carotene as independent variables, confirmed that β-carotene was independently associated with telomerase activity (β = 0.319, p = 0.012). Subjects affected by AD had significantly lower plasmatic levels of β-carotene (448 ± 66 mg/ml vs 497 ± 59 mg/ml, p = 0.001) and LTL (0.53 ± 0.25 vs 0.69 ± 0.29; p = 0.009) as compared with healthy controls. Β-carotene plasma level was associated with AD diagnosis (OR 0.988; IC95% 0.978-0.997; p = 0.013) independently of age, gender, smoking habit, ApoE genotype, and LTL.
Our data show that β-carotene may modulate telomerase activity in old age. Moreover, lower plasma β-carotene levels, correlating with peripheral telomerase activity, are associated with AD diagnosis independent of multiple covariates.
年龄增长是阿尔茨海默病（AD）最强的危险因素，确定能够区分生理衰老和 AD 的生物标志物，可能是新的预防策略的起点。在这些生物标志物中，端粒似乎是一个很有前途的靶点。有趣的是，富含类胡萝卜素的食物的高摄入量可能通过降低氧化应激来保护端粒。因此，与认知健康的受试者相比，AD 受试者的血浆 β-胡萝卜素浓度较低。在这项研究中，我们旨在调查低β-胡萝卜素可能与加速细胞衰老的标志物（包括白细胞端粒长度（LTL）和外周血单核细胞（PBMC）端粒酶活性）相关的假设，该研究在老年受试者的队列中进行。
该研究纳入了 68 名老年受试者，37 名 AD 患者和 31 名年龄匹配的健康对照者。所有受试者均检测了血浆 β-胡萝卜素水平、LTL 和外周端粒酶活性。
在所有人群中，β-胡萝卜素与端粒酶活性呈显著正相关（r=0.320，p=0.008），且独立于性别。以端粒酶活性为因变量，以年龄、性别、吸烟习惯和 β-胡萝卜素为自变量的模型证实，β-胡萝卜素与端粒酶活性独立相关（β=0.319，p=0.012）。患有 AD 的受试者血浆 β-胡萝卜素水平显著较低（448±66mg/ml 比 497±59mg/ml，p=0.001），LTL 水平也显著较低（0.53±0.25 比 0.69±0.29，p=0.009）。与健康对照组相比。β-胡萝卜素血浆水平与 AD 诊断相关（OR 0.988；95%CI 0.978-0.997；p=0.013），独立于年龄、性别、吸烟习惯、ApoE 基因型和 LTL。
我们的数据表明，β-胡萝卜素可能调节老年时的端粒酶活性。此外，与外周端粒酶活性相关的血浆β-胡萝卜素水平较低与 AD 诊断相关，且独立于多种混杂因素。
