IntroductionThe wearing-off phenomenon is characterized by the recurrence of motor and non-motor symptoms of Parkinsonism during a period free from levodopa. It is a pivotal aspect marking the end of the pharmacological “honeymoon” period in Parkinson’s disease (PD). A growing body of literature is connecting sex with the likelihood of developing fluctuations. We investigated such an association in a post-hoc analysis of the large WORK-PD study.MethodsWORK-PD analyzed the usability of the wearing-off questionnaire 19 (WOQ19) in clinical practice and included cross-sectional data on age, disease duration, time on levodopa, Hoehn and Yahr stage, and WOQ19 scores of 532 PD patients. In the present study, we selected patients with an exposure time to levodopa of at least 1 year.ResultsA total of 380 patients were included. Women reported a higher number of wearing-off symptoms than men (6.09 ± 3.39 vs 4.96 ± 3.11, p = 0.0006). Sex groups also differed in non-motor symptoms (2 ± 1.9 vs 1.5 ± 1.5, p = 0.021), particularly behavioral wearing-off scores being higher in women (p < 0.001). The latter were primarily featured by anxiety-related phenomena. Finally, there was a significant interaction between behavioral symptoms, sex, and age at onset (df = 2, F = 9.79, p < 0.0001), whereas no such interaction was observed with levodopa exposure and motor impairment, unlike motor symptoms.DiscussionWomen showed a greater propensity than men to experience wearing-off, particularly non-motor fluctuations on the anxiety spectrum. The latter may demonstrate a lesser reliance on dopamine compared to motor symptoms. This observation could be underpinned by biological variances between genders at the neurotransmitter level.
Background: Although disturbed sleep is frequent in patients with mild cognitive impairment (MCI) and dementia due to Alzheimer’s disease (AD), the association between sleep and tau pathology is unclear. Objective: This case series focused on measuring the sleep-wake rhythm over 7 days through actigraphy in patients diagnosed with MCI due to AD. Further, the association between sleep-wake cycle and tau deposition measured through positron emission tomography (PET) was explored. Methods: This case series included 6 MCI due to AD patients (2 women and 4 men, mean age 73.17±5.53 years), who completed neuropsychological testing, 7-day actigraphy, and tau PET imaging with radiolabeled compounds aimed to estimate the density and distribution of aggregated tau neurofibrillary tangles in the brain. Results: The case series indicated that patients with MCI due to AD who exhibited greater tau deposition in the frontal, parietal, and limbic regions, as well as in the precuneus and olfactory regions, also showed increased sleep fragmentation, as measured through actigraphy. Conclusion: The findings from this case series suggest a potential link between tau deposition in key brain regions associated with AD and both sleep fragmentation and sleep-wake cycle dysregulation in a small sample of patients with MCI due to AD. These preliminary results warrant further investigation in larger, more comprehensive studies to confirm and expand upon these findings.
IMPORTANCE Alzheimer disease (AD), a neurodegenerative disease characterized by beta-amyloid plaques and tau tangles in the brain, represents an unmet medical need with no fully approved therapeutics to modify disease progression. OBJECTIVE To investigate the safety and efficacy of crenezumab, a humanized monoclonal immunoglobulin G4 antibody targeting beta-amyloid oligomers, in participants with prodromal to mild (early) AD. DESIGN, SETTING, AND PARTICIPANTS Two phase 3 multicenter randomized double-blind placebo-controlled parallel-group efficacy and safety studies of crenezumab in participants with early AD, CREAD and CREAD2, were initiated in 2016 and 2017, respectively, and were designed to evaluate the efficacy and safety of crenezumab in participants with early AD. CREAD (194 sites in 30 countries) and CREAD2 (209 sites in 27 countries) were global multicenter studies. A total of 3736 and 3664 participants were screened in CREAD and CREAD2, respectively. A total of 3736 and 3664 participants were screened in CREAD and CREAD2, respectively. Both trials enrolled individuals aged 50 to 85 years with early AD. Participants with some comorbidities and evidence of cerebral infarction or more than 4 microbleeds or areas of leptomeningeal hemosiderosis on magnetic resonance imaging were excluded. After 2923 and 2858 were excluded, respectively, 813 participants in CREAD and 806 in CREAD2 were randomly assigned in a 1:1 ratio to either placebo or crenezumab. In the final analysis, there were 409 participants in the placebo group and 404 in the crenezumab group in CREAD and 399 in the placebo group and 407 in the crenezumab group in CREAD2. Data were analyzed up until January 2019 and August 2019, respectively. INTERVENTIONS Participants received placebo or 60 mg/kg crenezumab intravenously every 4 weeks for up to 100 weeks. MAIN OUTCOMES AND MEASURES The primary outcome was change from baseline to week 105 in Clinical Dementia Rating-Sum of Boxes (CDR-SB) score. RESULTS There were 813 participants in CREAD (mean [SD] age, 70.7 [8.2] years; 483 female and 330 male) and 806 in CREAD2 (mean [SD] age, 70.9 [7.7] years; 456 female and 350 male). Baseline characteristics were balanced between both groups. The between-group difference in mean change from baseline in CDR-SB score (placebo minus crenezumab) was -0.17 (95% CI, -0.86 to 0.53; P = .63) at week 105 in the CREAD study (88 placebo; 86 crenezumab). Compared with previous trials, no new safety signals were identified, and amyloid-related imaging abnormalities with edema were rare, mild, and transient. No meaningful changes in AD biomarkers were observed. Both studies were discontinued following a preplanned interim analysis indicating that CREAD was unlikely to meet the primary end point. CONCLUSIONS AND RELEVANCE Crenezumab was well tolerated but did not reduce clinical decline in participants with early AD.
Background: Meta-analyses indicated the breakdown of copper homeostasis in the sporadic form of Alzheimer's disease (AD), comprising copper decreases within the brain and copper increases in the blood and the pool not bound to ceruloplasmin (non-Cp Cu, also known in the literature as "free" copper). The calculated non-Cp Cu (Walshe's) index has many limitations.Methods: A direct fluorescent method for non-Cp Cu detection has been developed and data are presented herein. The study included samples from 147 healthy subjects, 36 stable mild cognitive impairment (MCI) and 89 AD patients, who were tested for non-Cp Cu through the direct method, total serum copper, ceruloplasmin concentration and o-dianisidine ceruloplasmin activity. The indirect non-Cp Cu Walshe's index was also calculated.Results: The direct method was linear (0.9-5.9 mu M), precise (within-laboratory coefficient variation of 9.7% for low and 7.1% for high measurements), and had a good recovery. A reference interval (0-1.9 mu M) was determined parametrically in 147 healthy controls (27-84 years old). The variation of non-Cp Cu was evaluated according to age and sex. Non-Cp Cu was 1.5 times higher in AD patients (regarding the upper value of the reference interval) than in healthy controls. Healthy, MCI and AD subjects were differentiated through the direct non-Cp Cu method [areas under the curve (AUC) = 0.755]. Considering a 95% specificity and a 1.91 mu mol/L cut-off, the sensitivity was 48.3% (confidence interval 95%: 38%-58%). The likelihood ratio (LR) was 9.94 for positive test results (LR +) and 0.54 for negative test result (LR -).Conclusions: The direct fluorescent test reliably and accurately measures non-Cp Cu, thereby determining the probability of having AD. Keywords: Alzheimer's disease; ceruloplasmin; copper; metal; mild cognitive impairment; non-ceruloplasmin copper.
BACKGROUND:Meta-analyses show that copper non-bound to ceruloplasmin (non-Cp Cu, also known as 'free' copper) in serum is higher in a percentage of Alzheimer's disease (AD) patients. Genetic heterogeneity in AD patients stratified on the basis of non-Cp Cu cut-off sustains the existence of a copper AD metabolic subtype.OBJECTIVE:In order to find evidence of the existence of a detectable metabolic subtype of AD associated to copper abnormalities, we explore the hypothesis of a neuroimaging pattern heterogeneity in an homogenous and well characterized AD population classified in two groups by the stratification of patients on the basis non-Cp Cu cut-off.METHOD:We assessed levels of copper, ceruloplasmin, non-Cp Cu, cerebrospinal levels of total Tau protein (h-tau), Thr 181 phosphorylated tau protein (P-tau) and β-amyloid 1-42, and APOE4 genotype in 66 AD patients and compared neuroimaging indices of a visual rating scale of cerebral atrophy and neurovascular burden in AD patients stratified in 'Normal' and 'High' non-Cp Cu groups.RESULTS:The stratification for non-Cp Cu originated AD groups which did not differ for medial temporal lobe atrophy, periventricular hyperintensities, deeper hyperintensities (including frontal, parietooccipital and temporal white matter hyperintensities), infratentorial hyperintensities indices, while they differed for global atrophy. More specifically, AD patients within the high non-Cp Cu group had a less severe burden of global atrophy (p=0.042).CONCLUSION:This neuroimaging heterogeneity between AD groups is suggestive of the existence of a copper metabolic subtype of AD; non-Cp Cu appears a good marker of this copper AD.
Abnormal handling of copper is the cause of Wilson disease (WD), a rare disorder typified by increased levels in plasma copper not-bound to ceruloplasmin (nCp-Cu, also known as ‘free’ copper). In Alzheimer’s disease (AD), meta-analyses show that copper decreases in brain but increases in serum, due to the nCp Cu component increase. Despite the similarities, a direct comparison of copper biological status in the two diseases has never been carried out. To fill this gap, we evaluated serum copper, ceruloplasmin, nCp-Cu and Cu:Cp in 385 CE and 336 healthy controls previously investigated that were compared with 9 newly diagnosed WD patients. We then assessed 24 h copper urinary excretion in 24 WD patients under D-penicillamine (D-pen) treatment and in 35 healthy controls, and compared results with those of AD patients participating to a D-pen phase II clinical trial previously published. After adjusting for sex and age, serum nCp-Cu and Cu:Cp resulted higher in AD and in WD than in healthy controls (both p < 0.001). While nCp-Cu was similar between AD and WD, Cu:Cp was higher in WD (p < 0.016). 24 h urinary copper excretion in AD patients (12.05 μg/day) was higher than in healthy controls (4.82 μg/day; p < 0.001). 77.8% of the AD patients under D-pen treatment had a 24 h urinary excretion higher than 200 μg/day, suggestive of a failure of copper control. This study provides new insight into the pathophysiology of copper homeostasis in AD, showing a failure of copper control and the Cu:Cp ratio as an eligible marker.
Objective Meta‐analyses show that nonbound ceruloplasmin (non‐Cp) copper (also known as free or labile copper) in serum is higher in patients with Alzheimer disease (AD). It differentiates subjects with mild cognitive impairment (MCI) from healthy controls. However, a longitudinal study on an MCI cohort has not yet been performed to assess the accuracy of non‐Cp copper for the prediction of conversion from MCI to AD during a long‐term follow‐up. Methods The study included 42 MCI converters and 99 stable MCI subjects. We assessed levels of copper, ceruloplasmin, non‐Cp copper, iron, transferrin, ferritin, and APOE genotype. A multiple Cox regression analysis—with age, sex, baseline Mini‐Mental State Examination, APOE4 , iron, non‐Cp copper, transferrin, ferritin, hypercholesterolemia, and hypertension as covariates—was applied to predict the conversion from MCI to AD. Results Among the evaluated parameters, the only significant predictor of conversion to AD was non‐Cp copper (hazard ratio = 1.23, 95% confidence interval = 1.03–1.47, p = 0.022); for each additional micromole per liter unit (μmol/l) of non‐Cp copper, the hazard increased by ∼20%. Subjects with non‐Cp copper levels >1.6μmol/l had a hazard conversion rate (50% of conversion in 4 years) that was ∼3× higher than those with values ≤1.6μmol/l (<20% in 4 years). The rate of conversion was similar between APOE4 carriers and noncarriers ( p = 0.321), indicating that the non‐Cp copper association was independent of APOE4 . Interpretation Non‐Cp copper appears to predict conversion from MCI to AD. These results encourage healthy life style choices and dietary intervention to modify this risk. ANN NEUROL 2014;75:574–580
OBJECTIVE:Verifying the validity and feasibility of the WOQ-19 as a useful tool in routine clinical practice and in management of patients. METHODS:532 consecutive Parkinson's disease (PD) patients were recruited from 6 different neurological outpatient units, specialized in movement disorders, of central Italy. Inclusion criteria were diagnosis of PD and any current pharmacological treatment of PD while exclusion criteria were evident cognitive or depressive impairment, infusion with dopamine agonists or Duodopa, or Deep Brain Stimulation therapy. Patients were asked to complete the Italian version of WOQ-19 before the neurological visit. A medical form for the collection of demographic and clinical data of patients and for the evaluation of comprehensibility and usability the WOQ-19 was filled by the neurologist during the visit. RESULTS:Our data confirmed that WOQ-19 was able to identify WO in 69% of patients, a percentage similar to the recently reported in the Italian WOQ-19 validation study. Motor symptoms were more frequent than non-motor symptoms (80% vs. 20%). Patients who experienced WO had a higher age of PD onset, more severe disease, longer disease duration and were more likely to be female. CONCLUSIONS:The WOQ-19 was understandable for the patient, easily administered and suitable for routine outpatient use. It could be also particularly useful in clinical practice in the early identification of non-motor symptoms, often under reported by patients and revealed only with clinical support.
Objective. To verify whether systemic biometals dysfunctions affect neurotransmission in living Alzheimer's disease (AD) patients. Methods. We performed a case-control study using magnetoencephalography to detect sensorimotor fields of AD patients, at rest and during median nerve stimulation. We analyzed position and amount of neurons synchronously activated by the stimulation in both hemispheres to investigate the capability of the primary somatosensory cortex to reorganize its circuitry disrupted by the disease. We also assessed systemic levels of copper, ceruloplasmin, non-Cp copper (i.e., copper not bound to ceruloplasmin), peroxides, transferrin, and total antioxidant capacity. Results. Patients' sensorimotor generators appeared spatially shifted, despite no change of latency and strength, while spontaneous activity sources appeared unchanged. Neuronal reorganization was greater in moderately ill patients, while delta activity increased in severe patients. Non-Cp copper was the only biological variable appearing to be associated with patient sensorimotor transmission. Conclusions. Our data strengthen the notion that non-Cp copper, not copper in general, affects neuronal activity in AD. Significance. High plasticity in the disease early stages in regions controlling more commonly used body parts strengthens the notion that physical and cognitive activities are protective factors against progression of dementia.
Objective. To verify whether systemic biometals dysfunctions affect neurotransmission in living Alzheimer’s disease (AD) patients.Methods. We performed a case-control study using magnetoencephalography to detect sensorimotor fields of AD patients, at rest and during median nerve stimulation. We analyzed position and amount of neurons synchronously activated by the stimulation in both hemispheres to investigate the capability of the primary somatosensory cortex to reorganize its circuitry disrupted by the disease. We also assessed systemic levels of copper, ceruloplasmin, non-Cp copper (i.e., copper not bound to ceruloplasmin), peroxides, transferrin, and total antioxidant capacity.Results. Patients’ sensorimotor generators appeared spatially shifted, despite no change of latency and strength, while spontaneous activity sources appeared unchanged. Neuronal reorganization was greater in moderately ill patients, while delta activity increased in severe patients. Non-Cp copper was the only biological variable appearing to be associated with patient sensorimotor transmission.Conclusions. Our data strengthen the notion that non-Cp copper, not copper in general, affects neuronal activity in AD.Significance. High plasticity in the disease early stages in regions controlling more commonly used body parts strengthens the notion that physical and cognitive activities are protective factors against progression of dementia.
INTRODUCTION:Due to growing evidence of sensorimotor integration impairment in focal task-specific hand dystonia, we aimed at describing primary sensory (S1) and primary motor (M1) cortex source activities and their functional cross-talk during a non-dystonia-inducing sensorimotor task free of biases generated by the interfering with the occurrence of dystonic movements. METHOD:Magnetoencephalographic brain signals and opponens pollicis (OP) electromyographic activities were acquired at rest and during a simple isometric contraction performed either alone or in combination with median nerve stimulation. The task was performed separately with the right and left hand by eight patients suffering from focal task-specific hand dystonia and by eight healthy volunteers. Through an ad hoc procedure Functional Source Separation (FSS), distinct sources were identified in S1 (FSS1) and M1 (FSM1) devoted to hand control. Spectral properties and functional coupling (coherence) between the two sources were assessed in alpha [8,13]Hz, beta [14,32]Hz and gamma [33,45]Hz frequency bands. RESULTS:No differences were found between spectral properties of patients and controls for either FSM1 or FSS1 cerebral sources. Functional coupling between FSM1 and FSS1 (gamma band coherence), while comparable between dystonic patients and healthy controls at rest, was selectively reduced in patients during movement. All findings were present in both hemispheres. DISCUSSION:Because previous literature has shown that gamma-band sensory-motor synchronization reflects an efficiency index of sensory-motor integration, our data demonstrate that, in dystonic patients, uncoupling replaces the functional coupling required for efficient sensory-motor control during motor exertion. The presence of bi-hemispheric abnormalities in unilateral hand dystonia supports the presence of an endophenotypic trait.
Copper dyshomeostasis leading to a labile Cu(2+) not bound to ceruloplasmin ("free" copper) may influence Alzheimer's disease (AD) onset or progression. To investigate this hypothesis, we investigated ATP7B, the gene that controls copper excretion through the bile and concentrations of free copper in systemic circulation. Our study analyzed informative ATP7B single-nucleotide polymorphisms (SNPs) in a case-control population (n=515). In particular, we evaluated the genetic structure of the ATP7B gene using the HapMap database and carried out a genetic association investigation. Linkage disequilibrium (LD) analysis highlighted that our informative SNPs and their LD SNPs covered 96% of the ATP7B gene sequence, distinguishing two "strong LD" blocks. The first LD block contains the gene region encoding for transmembrane and copper-binding, whereas the second LD block encodes for copper-binding domains. The genetic association analysis showed significant results after multiple testing correction for all investigated variants (rs1801243, odds ratio [OR]=1.52, 95% confidence interval [CI]=1.10-2.09, p=0.010; rs2147363, OR=1.58, 95% CI=1.11-2.25, p=0.010; rs1061472, OR=1.73, 95% CI=1.23-2.43, p=0.002; rs732774, OR=2.31, 95% CI=1.41-3.77, p<0.001), indicating that SNPs in transmembrane domains may have a stronger association with AD risk than variants in copper-binding domains. Our study provides novel insights that confirm the role of ATP7B as a potential genetic risk factor for AD. The analysis of ATP7B informative SNPs confirms our previous hypothesis about the absence of ATP7B in the significant loci of genome-wide association studies of AD and the genetic association study suggests that transmembrane and adenosine triphosphate (ATP) domains in the ATP7B gene may harbor variants/haplotypes associated with AD risk.
Copper dyshomeostasis leading to a labile Cu(2+) not bound to ceruloplasmin ("free" copper) may influence Alzheimer's disease (AD) onset or progression. To investigate this hypothesis, we investigated ATP7B, the gene that controls copper excretion through the bile and concentrations of free copper in systemic circulation. Our study analyzed informative ATP7B single-nucleotide polymorphisms (SNPs) in a case-control population (n=515). In particular, we evaluated the genetic structure of the ATP7B gene using the HapMap database and carried out a genetic association investigation. Linkage disequilibrium (LD) analysis highlighted that our informative SNPs and their LD SNPs covered 96% of the ATP7B gene sequence, distinguishing two "strong LD" blocks. The first LD block contains the gene region encoding for transmembrane and copper-binding, whereas the second LD block encodes for copper-binding domains. The genetic association analysis showed significant results after multiple testing correction for all investigated variants (rs1801243, odds ratio [OR]=1.52, 95% confidence interval [CI]=1.10-2.09, p=0.010; rs2147363, OR=1.58, 95% CI=1.11-2.25, p=0.010; rs1061472, OR=1.73, 95% CI=1.23-2.43, p=0.002; rs732774, OR=2.31, 95% CI=1.41-3.77, p<0.001), indicating that SNPs in transmembrane domains may have a stronger association with AD risk than variants in copper-binding domains. Our study provides novel insights that confirm the role of ATP7B as a potential genetic risk factor for AD. The analysis of ATP7B informative SNPs confirms our previous hypothesis about the absence of ATP7B in the significant loci of genome-wide association studies of AD and the genetic association study suggests that transmembrane and adenosine triphosphate (ATP) domains in the ATP7B gene may harbor variants/haplotypes associated with AD risk.
The link between biometals and Alzheimer's disease (AD) has been investigated with a focus on local metal accumulations. In this work, we have looked at systemic metal changes and computed a score (M-score) based on metal disarrangements to discriminate patients with AD from patients with vascular dementia (VaD) and from controls. We measured serum levels of iron, copper, ceruloplasmin, transferrin, and total antioxidant capacity (TAS), performed Apolipoprotein E (APOE) genotyping and calculated non-ceruloplasmin copper ('free' copper') levels, transferrin saturation, total iron binding capacity, and ceruloplasmin-transferrin ratio (Cp/Tf) in 93 patients with AD, 45 patients with VaD, and 48 controls. All subjects underwent biochemical, neuroimaging and cognitive evaluations. Significant differences were observed among the tested groups for the levels of copper, free copper, peroxides, and TAS and for the Cp/Tf with disparity in couple comparison. On this basis we created the M-score as linear combination of biometal variables and APOE genotype. Besides its ability to discriminate AD patients vs. controls (ROC AUC=90%), M-score was able to distinguish AD vs. VaD (ROC AUC=79%). Moreover, we calculated the sensitivity and the specificity for M-score and for the other significant variables: M-score reached the highest sensitivity without a relevant loss in terms of specificity. When we compared M-score with APOE genotype and Medial Temporal Atrophy score, it resulted statistically better than these diagnostic markers. In conclusion, we confirm the link between biometals and AD and suggest its potential as diagnostic tool. Further studies may elucidate its potential role as reliable diagnostic test.
Alzheimer's disease (AD) is the most common form of dementia in the elderly. The causes of AD are very complex but there is general agreement about the existence of a link between Alzheimer's disease and oxidative stress. The Glutathione S-transferases (GSTs) act to detoxify products of oxidation that cause damage to macromolecules. Particular attention has been focused on GST genes because polymorphisms are important determinants of disease risk.To evaluate if GSTA1, GSTM1, GSTP1, and GSTT1 genes are associated with LOAD we screened a case control population (n = 311).Differences in genotype distributions between AD patients and controls were found only for the GSTM1 null genotype (P<0.001). In addition, a logistic regression analysis also conferred a positive association between the GSTM1 null genotype and LOAD after adjustment for age and gender (OR = 2.09; 95%CI = 1.31-3.35). The GSTM1 enzyme detoxifies substances such as exogenous and endogenous metabolites and plays a regulatory role in cellular signaling. Previous studies have highlighted that GSTM1 has a role in neurodegenerative disorders, but no data have associated the GSTM1 gene with AD risk. Our outcome suggests that the GSTM1 null genotype is a risk factor for AD in Italian patients. (C) 2012 Elsevier B.V. All rights reserved.
It is now accepted that transition metals, such as iron and copper, are involved in the pathogenesis of the Alzheimer's disease (AD) through their participation in toxic oxidative phenomena. In this context, hemochromatosis (Hfe) and transferrin (Tf) genes are of particular importance, since they play a key role in iron homeostasis. Also, signs of liver distress which accompany metal dysmetabolisms have been shown to be linked to AD. In order to investigate whether and how all these factors are interconnected, in this study we have explored the relationship of the gene variants of Hfe H63D and C282Y and of Tf C2 with serum markers of iron status (iron, ferritin, TF, TF-saturation, ceruloplasmin -CP-, CP and TF serum concentrations (CP/TF) ratio), and of liver function (albumin, transaminases, prothrombin time-prothrombin time (PT)) in a sample of 160 AD patients and 79 healthy elderly controls. Albumin resulted in lower, PT longer and AST/ALT higher ratios in AD patients than in controls, indicating a distress of the liver. Also TF was lower and ferritin higher in AD. Multiple logistic regression backward analyses, performed to evaluate the effects of our biochemical variables upon the probability of developing AD, revealed that a one-unit TF serum-decrease increases the probability of AD by 80%, a one-unit albumin serum-decrease reduces this probability by 20%, and a one-unit increase of AST/ALT ratio generates a 4-fold probability increase. Patients who were carriers of the H63D mutation showed higher levels of iron, lower levels of TF and CP and higher CP/TF ratios, a panel resembling hemochromatosis. This picture was found neither in H63D non-carrier patients, nor in healthy controls. Our results suggest the existence of a link between Hfe mutations and iron abnormalities that increases the probability of developing AD when accompanied by a distress of the liver.
Different factors interact to develop neurodegeneration in patients with dementia and other neurodegenerative disorders. Oxidative stress and the ε4 allele of apolipoprotein E (ApoE) are associated with significant alteration in lipid metabolism, in turn connected to a variety of neurodegenerative diseases and aging. Thus, a better understanding of the pathogenetic pathways associated with lipid dyshomeostasis may elucidate the causes of neurodegenerative processes. To address this issue, we evaluated the effects of antioxidant status and APOE genotype on neurodegeneration in patients with dementia of the Alzheimer type (AD), with vascular dementia (VaD), and in elderly healthy controls. Eighty-two AD, 42 VaD patients, and 26 healthy controls were recruited and underwent medial temporal lobe atrophy (MTA) assessment, white matter hyperintensities rating (WMH), serum total antioxidant status assaying (TAS), and APOE genotyping. A logistic regression algorithm applied to our data revealed that a 0.01 mmol/L decrease of TAS concentration increased the probability of MTA by 24% (p=0.038) and that carriers of the APOE ε4 allele showed higher WMH scores (p=0.018), confirming that small variations in antioxidant systems homeostasis are associated with relevant modifications of disease risk. Furthermore, in individuals with analogous TAS values, the presence of the ε4 allele increased the predicted probability of having MTA. These outcomes further sustain the interaction of oxidative stress and APOE genotype to neurodegeneration.
The link between iron and Alzheimer's disease (AD) has been mainly investigated with a focus on the local accumulation of this metal in specific areas of the brain that are critical for AD. In the present study, we have instead looked at systemic variations of markers of iron metabolism. We measured serum levels of iron, ceruloplasmin, and transferrin and calculated the transferrin saturation and the ceruloplasmin to transferrin ratio (Cp/Tf). Cp/Tf and transferrin saturation increased in AD patients. Cp/Tf ratios also correlated positively with peroxide levels and negatively with serum iron concentrations. Elevated values of ceruloplasmin, peroxides, and Cp/Tf inversely correlated with MMSE scores. Isolated medial temporal lobe atrophy positively correlated with Cp/Tf and negatively with serum iron. All these findings indicate that the local iron accumulation found in brain areas critical for AD should be viewed in the frame of iron systemic alterations.