title: Occupational exposure to aluminum and its amyloidogenic link with cognitive functions.
abstract: As many other metals, aluminum is a widely recognized neurotoxicant and its link with neurodegenerative disorders has been the subject of scientific debate. One proposal focuses on amyloid β deposition (amyloidogenesis) as the key player in triggering neuronal dysfunction the so-called amyloid cascade hypothesis. We undertook this study first to investigate the cognition status of workers exposed to Al dust in an Al factory in Southern Cairo, second, to evaluate serum amyloid precursor protein (APP) and cathepsin D (CD) enzyme activity to study the possible role of Al in amyloidogenesis, and finally to explore the relation between these potential biomarkers and cognitive functions. The study was conducted on 54 exposed workers and 51 matched controls. They were subjected to questionnaire, neurological examination and a cognitive test battery, Addenbrooke's Cognitive Examination - Revised (ACE-R). Serum Al, APP and CD enzyme activity were measured. A significant increase of serum Al was found in the exposed workers with an associated increase in serum APP and decrement in CD activity. The exposed workers displayed poor performance on the ACE-R test. No significant correlation was detected between ACE-R test total score and either APP or CD activity. We concluded that occupational exposure to Al is associated with cognitive impairment. The effect of occupational Al exposure on the serum levels of APP and CD activity may be regarded as a possible mechanism of Al in amyloidogenesis. However, our findings do not support the utility of serum APP and CD activity as screening markers for early or preclinical cognitive impairment.
authors: Department of Occupational & Environmental Medicine, Faculty of Medicine, Cairo University, Egypt.
authors: N H
authors: NH
authors: Zawilla
authors: Department of Medical Biochemistry, Faculty of Medicine, Cairo University, Egypt. Electronic address: fatma.taha@kasralainy.edu.eg.
authors: F M
authors: FM
authors: Taha
authors: Department of Neurology, Faculty of Medicine, Cairo University, Egypt.
authors: N A
authors: NA
authors: Kishk
authors: Department of Occupational & Environmental Medicine, Faculty of Medicine, Cairo University, Egypt.
authors: S A
authors: SA
authors: Farahat
authors: Department of Neurology, Faculty of Medicine, Cairo University, Egypt.
authors: M
authors: M
authors: Farghaly
authors: Department of Neurology, Faculty of Medicine, Bani-suef University, Egypt.
authors: M
authors: M
authors: Hussein
mesh_terms: D000328:Adult; D000395:Air Pollutants, Occupational / Q000633:toxicity*; D000535:Aluminum / Q000097:blood / Q000633:toxicity*; D000686:Amyloidosis / Q000139:chemically induced* / Q000523:psychology; D016022:Case-Control Studies; D002617:Chemical Industry; D003072:Cognition Disorders / Q000139:chemically induced*; D003430:Cross-Sectional Studies; D004391:Dust; D006801:Humans; D008875:Middle Aged; D016273:Occupational Exposure; D055815:Young Adult
chemical_list: D000395:Air Pollutants, Occupational; D004391:Dust; D000535:Aluminum
keywords: ACE-R test; Aluminum; Amyloid precursor protein; Amyloidogenesis; Cathepsin D activity; Occupational exposure