Affiliations: [a] Vascular Biology and Mass Spectrometry Laboratory, Department of Experimental Medicine, Sapienza University, Rome, Italy | [b] Laboratory of Clinical and Behavioral Neurology, IRCCS Santa Lucia Foundation, Rome, Italy | [c] Unit of Geriatric Oncology, INRCA; Rome, Italy | [d] Department of Neuroscience, Tor Vergata University, Rome, Italy
Correspondence:
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Correspondence to: Luigi Iuliano, M.D., Sapienza University of Rome, Department of Experimental Medicine, Unit of Vascular Medicine, ~Vascular Biology & Mass Spectrometry Lab, Corso della Repubblica, 79 04100 Latina, Italy. Tel.: +39 0773 474098; Fax: +39 06 62 29 1089; E-mail: luigi.iuliano@uniroma1.it.
Abstract: Oxidative stress, which contributes to neuronal damage, is thought to be a pathophysiological mechanism of Alzheimer's disease (AD). Markers of oxidative stress may appear early in the preclinical, mild cognitive impairment (MCI) phase of AD. We investigated the interaction among enzymatic-derived oxysterols (24S-hydroxycholesterol and 27-hydroxycholesterol), markers of oxidative stress, including free radical-related oxysterols (7β-hydroxycholesterol and 7-ketocholesterol), and vitamin E in AD patients and two amnestic MCI subtypes, amnestic single-domain MCI (a-MCI) subjects, and multi-domain MCI (md-MCI) subjects, compared to healthy control subjects (HC). The study included 37 patients with AD, 24 with a-MCI, 29 with md-MCI, and 24 HC. Plasma assessments were made using isotope dilution-mass spectrometry. Although we found no significant change in free radical- or enzymatic-derived oxysterol concentrations in AD or MCI patients, vitamin E levels corrected for cholesterol were reduced in AD patients compared to HC. Results suggest that AD patients have upregulated cerebral oxidative stress or a nutritional deficit of vitamin E. The oxysterols investigated here are not useful markers for diagnosing AD or MCI.
