Cited by 235Dementia and Cognitive Impairment ResearchAntioxidant Activity and Oxidative StressAlzheimer's disease research and treatments

Plasma chain-breaking antioxidants in Alzheimer's disease, vascular dementia and Parkinson's disease

Foy, C.J.·1999·QJM

Abstract

We studied the plasma chain-breaking antioxidants alpha carotene, beta carotene, lycopene, Vitamin A, Vitamin C, Vitamin E and a measure of total antioxidant capacity, TAC, in 79 patients with Alzheimer's disease (AD), 37 patients with vascular dementia (VaD), 18 patients with Parkinson's disease and dementia (PDem), and 58 matching controls, together with 41 patients with Parkinson's disease (PD) and 41 matching controls. Significant reductions in individual antioxidants were observed in all dementia groups. When compared to controls, the following were reduced: Vitamin A in AD (p < 0.01) and VaD (p < 0.001); Vitamin C in AD (p < 0.001), VaD (p < 0.001) and PDem (p < 0.01); Vitamin E in AD (p < 0.01) and VaD (p < 0.001); beta carotene in VaD (p = 0.01); lycopene in PDem (p < 0.001). Lycopene was also reduced in PDem compared to AD (p < 0.001) and VaD (p < 0.001). Antioxidant levels in PD were not depleted. No significant change in TAC was seen in any group. The reduction in plasma chain-breaking antioxidants in patients with dementia may reflect an increased free-radical activity, and a common role in cognitive impairment in these conditions. Increased free-radical activity in VaD and PDem could be associated with concomitant AD pathology. Individual antioxidant changes are not reflected in TAC.

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  • Patients with neurological disorders such as PD have decreased plasma levels of vitamin C; level of vitamin C can be considered a biomarker of PD progression.

    “Patients suffering from neurological disorders such as PD have been reported to have decreased plasma levels of vitamin C; the level of vitamin C can be considered a biomarker of PD progression (Foy et al. 1999).”

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  1. King D, Playfer JR, Roberts NB. Concentrations of vitamins Bull 1988; 24:709-11.

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Authors
Foy, C. J.
Affiliations
Queen's University Belfast (GB)
Corresponding author
Foy, C.J.
Venue
QJM
Published
1999-01-01
Volume
92
Issue
1
Pages
39-45
ISSN
  • 0033-5622 (ISSN-L)
  • 1460-2393
OpenAlex
W2139931759
Cited by
235
References
37
Citations by year
2026: 1 · 2025: 4 · 2024: 9 · 2023: 9 · 2022: 7 · 2021: 13 · 2020: 9 · 2019: 7 · 2018: 7 · 2017: 7 · 2016: 11 · 2015: 10 · 2014: 13 · 2013: 6 · 2012: 10
FWCI
8.56
Type
journal article
Language
en
Open access
closed
Locations
  • QJM (publishedVersion)
  • PubMed (publishedVersion)
  • Research Portal (Queen's University Belfast) (submittedVersion)
Topics
  • Health Sciences › Medicine › Psychiatry and Mental health › Dementia and Cognitive Impairment Research
  • Health Sciences › Medicine › Biochemistry › Antioxidant Activity and Oxidative Stress
  • Health Sciences › Medicine › Physiology › Alzheimer's disease research and treatments
Keywords
plasma antioxidants, chain-breaking antioxidants, Alzheimer's disease, vascular dementia, Parkinson's disease, Parkinson's disease dementia, vitamin E, vitamin C, vitamin A, beta-carotene, lycopene, alpha-carotene, total antioxidant capacity, free radicals, oxidative stress, cognitive impairment
MeSH terms
Aged, Aged, 80 and over, Alzheimer Disease, Antioxidants, Carotenoids, Female, Free Radicals, Humans, Male, Middle Aged, Oxidation-Reduction, Parkinson Disease, Vitamins, Dementia, Vascular

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