Higher Aluminum Concentration in Alzheimer’s Disease After Box–Cox Data Transformation

Abstract

Evidence regarding the role of mercury and aluminum in the pathogenesis of Alzheimer's disease (AD) remains controversial. The aims of our project were to investigate the content of the selected metals in brain tissue samples and the use of a specific mathematical transform to eliminate the disadvantage of a strong positive skew in the original data distribution. In this study, we used atomic absorption spectrophotometry to determine mercury and aluminum concentrations in the hippocampus and associative visual cortex of 29 neuropathologically confirmed AD and 27 age-matched controls. The Box-Cox data transformation was used for statistical evaluation. AD brains had higher mean aluminum concentrations in the hippocampus than controls (0.357 vs. 0.090 μg/g; P = 0.039) after data transformation. Results for mercury were not significant. Original data regarding microelement concentrations are heavily skewed and do not pass the normality test in general. A Box-Cox transformation can eliminate this disadvantage and allow parametric testing.

Dietary flavonoid fisetin regulates aluminium chloride-induced neuronal apoptosis in cortex and hippocampus of mice brain

“…In this study, we demonstrate that AlCl 3 induces toxic fibrillar Aβ aggregation in cortex and hippocampus of mice brain. Moreover documented reports denote that aluminium was specifically deposited in cortex and hippocampal regions of AD patients and also in rodents exposed to aluminium [33,34,35]. These reports support documented report denotes that Amyloid-β 42 induces neuronal cell death via ASK-1 [36] and JNK activation [37].…”

Systematic review of potential health risks posed by pharmaceutical, occupational and consumer exposures to metallic and nanoscale aluminum, aluminum oxides, aluminum hydroxide and its soluble salts

“…The 27 subjects (12 women and 15 men, mean age 76 years) in the referent group had no signs of AD or other degenerative dementias on autopsy. Different statistical approaches used by Rusina et al (2011) provided somewhat different results: higher mean Al concentrations in the hippocampus were found in AD patients compared with the healthy individuals (0.357 vs 0.090 μg/g; p = 0.039) after Box-Cox data transformation, but not after standard logarithmic transformation to correct deviations from normality.…”

“…Rusina et al (2011) measured Al in brains from 29 deceased patients (mean age 79 years, women to men ratio 20:9) with neuropathologically confirmed AD. All these samples fulfilled the National Institute of Aging (Hyman et al 2012, McKhann et al 2011) and Reagan Institute (Newell et al 1999) AD diagnostic criteria.…”

“…As with all of the in vitro assays (Table 3), Aremu et al (2011), Castorina et al (2010), Gatta et al (2011), Nday et al (2010), and Yang et al (2011) provided no justification for the Al concentrations used in their assays. None of the authors compared their Al concentrations examined in vitro (Table 3) to the Al concentrations measured in human brain or other tissues (e.g., Akatsu et al 2011, House et al 2012, Rusina et al 2011). …”

Macrophages adhesion rate on Ti-6Al-4V substrates: polishing and DLC coating effects

“…Many studies have shown that Co -, Cr -, and Mo -ions are considered toxic, carcinogenic and also able to promote inflammation (Andrews et al, 2011;Hinüber et al, 2010;Jakobsen et al, 2007). Aluminum is also considered to be a risk factor for the pathogenesis of Alzheimer's disease (McLachlan et al, 1990;Rusina et al, 2011). However, Ti-6Al-4V has an advantage over Co-28Cr-26Mo because of the presence of Vanadium.…”