Role of prothrombotic polymorphisms in successful or unsuccessful aging.

The study of the genetic profile of centenarians aims to identify the genes and allelic variants which may influence a greater life expectancy and that can be considered as predisposing factors associated to the aging diseases, such as Alzheimer. Centenarians, that represent a cohort of selected survivors, show an hypercoagulability state characterised by striking signs of high coagulation enzyme activity, as directly assessed by the tested higher plasma level of some important factors involved in the haemostasis balance. Anyway, these individuals seem to have a reduced susceptibility to dementia, as well as to cardiovascular events. In this study we analyze the frequencies of Leiden Factor V polymorphism (G1691A), and G20210A of prothrombin (FII) in three cohorts of subjects: patients with Alzheimer's disease (unsuccessful aging), nonagenarians (successful aging) and young healthy controls, to assess whether allelic variants associated to the modification of haemostatic system function, may play a role in the protection or susceptibility to Alzheimer disease, as well as to reach a successful aging. No significant differences were observed in the frequencies of the three groups studied. These results indicate that the presence or absence of the gene variants examined did not influence the achievement of advanced age and are not risk factors for Alzheimer's disease. The state of hypercoagulability and the possession of these risk alleles appear to be compatible with the achievement of longevity and are not implied as risk factors in Alzheimer disease development.

Sharing pathogenetic mechanisms between acute myocardial infarction and Alzheimer's disease as shown by partially overlapping of gene variant profiles.

Gene variants that promote inflammation and cholesterol metabolism have been associated with acute myocardial infarction (AMI) and Alzheimer's disease (AD). We investigated a panel of relevant polymorphisms to distinguish genetic backgrounds for AMI and AD: IL10 -1082G/A, IL6 -174G/C, TNF -308G/A, IFNG +874T/A, SERPINA3 -51G/T, HMGCR -911C/A, APOE ε2/3/4 (280 AMI cases, 257 AD cases, and 1307 population controls, all Italian (presumed risk alleles are shown in bold). Six genetic risk sets I to VI were identified by fuzzy latent classification: I had low risk; II and III had low risk before age 65 (II, III); low risk sets lacked pro-inflammatory alleles for HMGCR-TNF-APOE. Pro-inflammatory alleles for SERPINA3-IL10-IFNG were found for high risk sets IV to VI. Set IV 'AMI < age 40, AD < age 65' included risk alleles for HMGCR. Set V 'AMI over a broad range of age' included risk alleles for TNF+IL6. Set VI 'AMI at ages 40 to 55, AD ages 65+' included APOE ε4. Close resemblance to the high risk sets, as indicated by membership scores close to one, defined high relative risks. We conclude that AMI and AD share genetic backgrounds involving cholesterol metabolism and the upregulation of inflammation and that gene-gene interactions in relevant sets of genes may be useful in defining inherited risk for common disorders.

Altered glycosylation profile of purified plasma ACT from Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is one of the most frequent cause of neurodegenerative disorder in the elderly. Inflammation has been implicated in brain degenerative processes and peripheral markers of brain AD related impairment would be useful. Plasma levels of alpha-1-antichymotrypsin (ACT), an acute phase protein and a secondary component of amyloid plaques, are often increased in AD patients and high blood ACT levels correlate with progressive cognitive deterioration. During inflammatory responses changes in the micro-heterogeneity of ACT sugar chains have been described. METHODS: N-Glycanase digestion from Flavobacterium meningosepticum (PNGase F) was performed on both native and denatured purified ACT condition and resolved to Western blot with the purpose to revealed the ACT de-glycosylation pattern.Further characterization of the ACT glycan profile was obtained by a glycoarray; each lectin group in the assay specifically recognizes one or two glycans/epitopes. Lectin-bound ACT produced a glyco-fingerprint and mayor differences between AD and controls samples were assessed by a specific algorithms. RESULTS: Western blot analysis of purified ACT after PNGase F treatment and analysis of sugar composition of ACT showed significantly difference in "glyco-fingerprints" patterns from controls (CTR) and AD; ACT from AD showing significantly reduced levels of sialic acid. A difference in terminal GlcNac residues appeared to be related with progressive cognitive deterioration. CONCLUSIONS: Low content of terminal GlcNac and sialic acid in peripheral ACT in AD patients suggests that a different pattern of glycosylation might be a marker of brain inflammation. Moreover ACT glycosylation analysis could be used to predict AD clinical progression and used in clinical trials as surrogate marker of clinical efficacy.

Blood inflammatory proteins and risk of incident depression in the elderly.

BACKGROUND: It is unclear whether high levels of blood inflammatory proteins are associated with the risk of developing depression in late life. METHODS: Blood C-reactive protein, interleukin (IL)-6, 1 -antichymotrypsin (ACT), intercellular adhesion molecule 1, and tumor necrosis factor were measured in an elderly cohort (n = 968). Major depression diagnosed according to clinical criteria and relevant depressive symptoms measured by the Geriatric Depression Scale (score 6 10) were assessed at baseline and 4 year later. RESULTS: Baseline IL-6 and ACT were increased in both prevalent major depression and relevant depressive symptoms. Baseline ACT was increased in incident major depression. All associations weakened below significance after adjustment for possible confounders and multiple comparisons. CONCLUSIONS: Blood inflammatory proteins do not predict the risk of developing depression in older age.

Role of cyclooxygenase-2 and 5-lipoxygenase polymorphisms in Alzheimer's disease in a population from northern Italy: implication for pharmacogenomics.

Alzheimer's disease (AD) is a neurodegenerative disorder clinically characterized by cognitive deficit with progressive worsening of memory. Recent data indicate that neurons, as well as other brain cells, can express enzymes such as cyclooxygenases (COXs) and 5-lipoxygenase (5-LO) which are considered important in inflammatory cells. Moreover, it has been demonstrated that COX-2 and 5-LO enzymes play a considerable role in the pathophysiology of AD. In order to assess the possible role of COX-2 and 5-LO single nucleotide polymorphisms (SNPs) in AD, we examined their distribution in 341 AD patients and 190 controls from Northern Italy. A significant difference was observed in the distribution of the -765G COX-2 and -1708A 5-LO alleles between AD cases and controls (p=0.03 for -765G/C COX-2 SNP; and p=0.007 for -1708G/A 5-LO SNP). Hence, COX-2 -765G and 5-LO -1708A alleles were overrepresented in AD patients and underrepresented in controls. Our data suggest that these alleles of COX-2 and 5-LO could be risk factors for AD. These results seem of some importance for a pharmacogenomic approach.

Multivariable network associated with cognitive decline and dementia.

Data mining of a large data base from the population longitudinal study named "The Conselice Study" has been the focus of the present investigation. Initially, 65 years old or older participants were interviewed, underwent medical and cognitive examination, and were followed up for 5 years: 937 subjects completed the follow-up. Relationships of 35 genetic and/or phenotypic factors with incident cognitive decline and dementia were investigated. The new mathematical approach, called the Auto Contractive Map (AutoCM), was able to show the differential importance of each variables. This new variable processing created a semantic connectivity map that: (a) preserved non-linear associations; (b) showed connection schemes; (c) captured the complex dynamics of adaptive interactions. This method, based on an artificial adaptive system, was able to define the association strength of each variable with all the others. Few variables resulted to be aggregation points and were considered as major biological hubs. Three hubs were identified in the hydroxyl-methyl-gutaryl-CoA reductase (HMGCR) enzyme, plasma cholesterol levels and age. Gene variants and cognate phenotypic variables showed differential degrees of relevance to brain aging and dementia. This data analysis method was compared with another mathematical model called mutual information relevance network and results are presented and discussed.

Pathophysiology of age-related diseases.

A Symposium regarding the Pathophysiology of Successful and Unsuccessful Ageing was held in Palermo, Italy on 7-8 April 2009. Three lectures from that Symposium by G. Campisi, L. Ginaldi and F. Licastro are here summarized. Ageing is a complex process which negatively impacts on the development of various bodily systems and its ability to function. A long life in a healthy, vigorous, youthful body has always been one of humanity's greatest dreams. Thus, a better understanding of the pathophysiology of age-related diseases is urgently required to improve our understanding of maintaining good health in the elderly and to program possible therapeutic intervention.

Adipocytokines in Down's syndrome, an atheroma-free model: Role of adiponectin.

Down's syndrome (DS) is the most frequent chromosomal aberration in men. Moreover DS is considered an atheroma-free model. Plasma levels of interleukin-6 (IL-6), tumor necrosis factor-alpha high sensitivity (hsTNF-alpha), leptin and adiponectin from non-demented DS subjects of three different age cohorts (2-14, 20-50 and above 60 years) and healthy controls were measured. No clinical and sub-clinical inflammation was apparent in DS patients. Plasma levels of hsTNF-alpha, IL-6 and leptin were higher in children than in adult and old DS subjects. Instead, serum levels of adiponectin were increased in older DS patients than in DS children and adults. High levels of circulating adiponectin might protect DS from clinical complications of atherosclerosis.

Alpha 1 antichymotrypsin genotype is associated with increased risk of prostate carcinoma and PSA levels.

BACKGROUND: Prostate cancer (PCa) is the most common non-skin cancer among men in Western countries. Inflammation appears to be involved in the pathogenesis of PCa. Recent studies have shown that many inflammatory genes are associated with the risk of PCa. Alpha 1 antichymotrypsin (ACT) is an acute phase protein and it is part of the circulating prostate specific antigen (PSA). PATIENTS AND METHODS: Allele and genotype frequencies of a promoter single nucleotide polymorphism (SNP) in ACT gene were investigated in patients with benign prostate hypertrophy (BHP) or PCa and controls. RESULTS: The G allele was more represented in PCa patients (odds ratio = 2.349). The PSA levels and prostatic volume did not correlate with the ACT genotype. However, stratifying subjects by age, a correlation of PSA levels and the GG genotype in young PCa patients was found. CONCLUSION: Carriers of the ACT G allele are at risk of developing PCa and genotyping healthy subjects could be a new approach for early prevention.

Endogenous sex hormones as risk factors for dementia in elderly men and women.

BACKGROUND: The associations of endogenous sex hormones with risk of dementia in the elderly population are not well known. METHODS: The relationship of baseline serum total estradiol (E2) and free testosterone (FT) to 4-year risk of all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VaD) was examined in a dementia-free, population-based cohort of 433 women (mean age 74 years) and 376 men (mean age 73 years). Multivariable proportional hazards regression was used to adjust for sociodemographic and lifestyle variables, body mass index, apolipoprotein E genotype, cardiovascular conditions, and homocysteinemia. RESULTS: Dementia developed in 71 women (46 AD, 21 VaD) and 39 men (23 AD, 12 VaD). In women with high E2 (serum E2 >or= 10 pg/mL), the multivariable-adjusted hazard ratio (HR) for dementia was 1.75 (95% confidence interval [CI], 1.06-2.89). The corresponding multivariable-adjusted HR for AD was 1.94 (95% CI, 1.04-3.61), whereas no association was found for VaD. No association with dementia was found for serum FT in women and for either serum E2 or FT in men. CONCLUSION: High serum E2 is an independent predictor for dementia and AD in elderly women.

Apolipoprotein E genotypic frequencies among Down syndrome patients imply early unsuccessful aging for ApoE4 carriers.

Down syndrome (DS) might be considered a model for unsuccessful and early aging, possibly accelerated for those who carry the APOE4 allele associated with common age-related diseases, e.g., Alzheimer's disease and a poor prognosis after acute myocardial infarction, causing lower ApoE4 frequencies among the very old in general populations. We compared ApoE genotypic frequencies found for healthy adults (n = 211, age < 40; n = 79, ages 70-79; n = 71, ages > 90) to those found for DS patients (n = 106, mean age 9 years), all living in western Sicily. We found that the frequency of the ApoE23 genotype increased with age among the healthy adults (8.5%, 6.4%, 19.7%; p = 0.024) while ApoE34 frequency decreased (16.1%, 12.6%, 4.1%; p = 0.012). DS patients had APOE34 genotypic frequencies very similar to those found in septuagenarians (9%; p = 0.005). Analyzing results according to surviving rate of persons with DS, an age-related reduction of ApoE3/4 genotype frequency was found comparing =5 years old to >5 years old DS subjects. These results highlight DS as a model to understand the role of APOE4 allele in unsuccessful ageing considering that a number of proinflammatory supernumerary genes (Cu/Zn superoxide dismutase, Ets-2 transcription factors, Down syndrome critical region 1, stress-inducible factor, interferon-alpha receptor and the amyloid precursor protein) are located on chromosome 21 and are implied in the pathologic processes of DS.

The hydroxy-methyl-glutaryl CoA reductase promoter polymorphism is associated with Alzheimer's risk and cognitive deterioration.

A link between cholesterol and Alzheimer's disease (AD) had been suggested. Hydroxy-methylglutaryl-coenzyme A reductase (HMGCR) is the rate limiting enzyme in the synthesis of cholesterol. A single nucleotide polymorphism (SNP) in the promoter of this gene, never described in Italian AD population, was investigated in case-control studies. Genotype distribution and allele frequency in two groups of AD patients and non demented controls were investigated. A cohort of AD patients were also followed up for 2 years, cognitive performances recorded and a possible influence of this SNP on the disease progression was tested. The CC genotype of the HMGCR gene was associated with a reduced risk of AD. Conversely the A allele of this polymorphism was over represented in AD patients. The presence of the A allele was also associated with an accelerated cognitive deterioration in AD patients followed up for 2 years. However, transfection experiments showed that this polymorphism did not directly influence functional activity in luciferase reporter gene assays. This polymorphism of the HMGCR gene appears to be linked to both AD risk and disease progression. Present findings reinforce the notion that abnormal regulation of cholesterol metabolism is a key factor in the pathogenesis of the disease.

The G51S purine nucleoside phosphorylase polymorphism is associated with cognitive decline in Alzheimer's disease patients.

Alzheimer's disease (AD) is a polygenic and multifactorial complex disease, whose etiopathology is still unclear, however several genetic factors have shown to increase the risk of developing the disease. Purine nucleotides and nucleosides play an important role in the brain. Besides their role in neurotransmission and neuromodulation, they are involved in trophic factor release, apoptosis, and inflammatory responses. These mediators may also have a pivotal role in the control of neurodegenerative processes associated with AD. In this report the distribution of the exonic G/A single nucleotide polymorphism (SNP) in purine nucleoside phosphorylase (PNP) gene, resulting in the amino acid substitution serine to glycine at position 51 (G51S), was investigated in a large population of AD patients (n=321) and non-demented control (n=208). The PNP polymorphism distribution was not different between patients and controls. The polymorphism distribution was also analyzed in AD patients stratified according to differential progressive rate of cognitive decline during a 2-year follow-up. An increased representation of the PNP AA genotype was observed in AD patients with fast cognitive deterioration in comparison with that from patients with slow deterioration rate. Our findings suggest that the G51S PNP polymorphism is associated with a faster rate of cognitive decline in AD patients, highlighting the important role of purine metabolism in the progression of this neurodegenerative disorder.

Polymorphisms of pro-inflammatory genes and Alzheimer's disease risk: a pharmacogenomic approach.

Clinically and pathologically Alzheimer's disease (AD) represents a sequential progressive neurodegenerative disorder. AD is etiologically heterogeneous and accounts for a majority of dementia in western societies. Inflammation clearly occurs in pathologically vulnerable regions of the AD brain and the search for genetic factors influencing the pathogenesis of AD has lead to the identification of numerous gene polymorphisms that might act as susceptibility modifiers. Accordingly, several reports have indicated that the risk of AD is substantially influenced by several genetic polymorphisms in the promoter region, or other untranslated regions, of genes encoding inflammatory mediators, although not all the studies were replied. Here, we review several data suggesting that inflammatory genetic variation may contribute to AD susceptibility. All together this information may represent the basis both for future recognition of individuals at risk and for the pharmacogenomic driving of drug responsiveness.

Blood inflammatory markers and risk of dementia: The Conselice Study of Brain Aging.

Incidence studies of blood inflammatory markers as predictors of dementia in older age are few and did not take into account hyperhomocysteinemia, although this condition is associated with both inflammation and increased risk of dementia. We investigated the relationships of baseline serum C-reactive protein (CRP), serum interleukin 6 (IL6), plasma alpha-1-antichymotrypsin, and hyperhomocysteinemia (defined as plasma total homocysteine>15 micromol/L) with risk of incident Alzheimer's disease (AD) and vascular dementia (VaD) in a dementia-free Italian population-based elderly cohort (n=804, 53.2% women, mean age 74 years) with 4 years of follow-up. No inflammatory marker, alone or in combination, predicted AD risk whereas the combination of high CRP and high IL6 was associated with risk of VaD (HR, 2.56; 95%CI, 1.21-5.50) independently of socio-demographic confounders, traditional risk factors and hyperhomocysteinemia. By contrast, in the same model, hyperhomocysteinemia was independently associated with AD (HR, 1.91; 95%CI, 1.02-3.56) but not VaD risk. Blood inflammatory markers are associated with increased VaD risk but do not predict AD, which seems selectively associated with hyperhomocysteinemia.

Plasma nerve growth factor (NGF) and inflammatory cytokines (IL-6 and MCP-1) in young and adult subjects with Down syndrome: an interesting pathway.

OBJECTIVES: Down's syndrome (DS) is the most frequent chromosomal aberration in men and it is invariably associated with mental retardation. MATERIAL AND METHODS: Plasma levels of nerve growth factor (NGF), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) from non demented DS subjects of three different age-cohorts (2-14 years; 20-50 yrs; >60 yrs) and healthy controls were measured. No clinical and sub-clinical inflammation was apparent in DS patients. RESULTS: Plasma levels of NGF were higher in children, adult and old DS subjects than in controls. However, a significant age-related decrease of NGF levels was present in DS subjects. Serum levels of IL-6 and MCP-1 were also increased in DS children and adults, but not in older DS patients. CONCLUSIONS: High levels of circulating NGF might protect DS from clinical complications of atherosclerosis. However, the striking decrement of peripheral NGF levels with advancing age may predispose DS to clinical manifestation of dementia after adulthood.

Apolipoprotein E e4 allele affects risk of hyperhomocysteinemia in the elderly.

BACKGROUND: Apolipoprotein E (APOE) plays a central role in VLDL metabolism. Both APOE e4 allele (APOE4) and C-reactive protein (CRP) are associated with greater risk of dementia and vascular disease, but APOE4 carriers have lower blood concentrations of CRP than do noncarriers, possibly through a mechanism favoring the clearance of the CRP VLDL-bound fraction. Homocysteine, another risk factor for vascular disease and dementia, also binds to VLDL in blood. However, the association between APOE4 and hyperhomocysteinemia has never been thoroughly investigated. OBJECTIVE: We investigated in an elderly population whether 1) APOE4 is associated with hyperhomocysteinemia [plasma total homocysteine (tHcy) > 15 micromol/L], 2) hyperhomocysteinemia affects the association between APOE4 and high CRP (serum CRP > 3 mg/L), and 3) B vitamin status affects these associations. DESIGN: APOE4 genotypes were assessed and tHcy, CRP, and serum concentrations of folate and vitamin B-12 were measured in 671 cognitively healthy subjects (52% women; mean age: 73 y) from an Italian population-based prospective cohort study. RESULTS: APOE4 carriers without high CRP [multivariate-adjusted odds ratio (OR): 0.22; 95% CI: 0.08, 0.59] had a lower risk of hyperhomocysteinemia than did noncarriers. The risk of high CRP was lower in APOE4 carriers without hyperhomocysteinemia (multivariate-adjusted OR: 0.51; 95% CI: 0.31, 0.85) than in noncarriers. The associations were not affected by B vitamin status. CONCLUSION: Independently from B vitamin status, APOE4 carriers have a lower risk of hyperhomocysteinemia and of high CRP than do noncarriers, but the presence of one condition attenuates the association of APOE4 with the other condition.

VEGF gene and phenotype relation with Alzheimer's disease and mild cognitive impairment.

BACKGROUND: The expression of vascular endothelial growth factor (VEGF) represents one potential mechanism whereby vascular and Alzheimer's disease (AD) pathologies are related. The authors investigated whether AD cases, especially those having a rapid cognitive decline, more commonly carried a functional promoter gene variant for VEGF (-2578C/A) and showed elevated plasma levels of Vegf. In addition, the authors investigated whether patterns of association also were found for mild cognitive impairment (MCI) and conversion from MCI to AD. METHODS: Group 1 included 317 AD cases and 320 unaffected control subjects. Group 2 included 113 MCI patients and 130 control subjects. Plasma levels of Vegf were measured by chemiluminescence for a subset of group 1. Genotype determinations were made for all subjects. FINDINGS: The VEGF AA genotype was associated with an increased risk of developing AD (OR = 1.616, p = 0.046). This genotype also was associated with an accelerated cognitive decline in APOE small epsilon4 positive patients with AD (AA vs. CC OR = 6.5, p = 0.04). The VEGF AA genotype was a risk factor for MCI (OR = 2.5, p = 0.037) and MCI conversion to AD in APOE small epsilon4+ (OR = 6.5, CI = 2.014-20.980; p = 0.002). Vegf plasma levels were higher in patients with AD than controls (230 pg/mL vs. 42 pg/mL), and were even higher in those patients with a fast cognitive decline and the APOE epsilon4 allele. INTERPRETATION: Modulation of VEGF expression is a potential mechanism associated with the risk of developing AD and its clinical deterioration.

Impaired regulation of immune responses in cognitive decline and Alzheimer's disease: lessons from genetic association studies.

Altered levels of cytokines and acute-phase proteins have been described in the blood and brain of patients with Alzheimer's disease. Microglia are resident cells of the brain and metabolic upregulation of these cells may play a crucial role in the development of the neurodegeneration associated with Alzheimer's disease. Studies focusing on gene polymorphisms of molecules with immune regulatory function have demonstrated an association with increased risk of the disease and confirmed the pivotal role of immune responses in Alzheimer's disease pathogenesis. Several gene variants may also influence the rate of the cognitive decline associated with the disease. A definite immune-related gene polymorphism profile may be a feature of a limited group of patients with early onset of the disease and fast clinical deterioration. Only this group of patients may benefit from anti-inflammatory treatment.

Metabolic Syndrome: prevalence and prediction of mortality in elderly individuals.

OBJECTIVE: Little is known about the prevalence of the metabolic syndrome among elderly people in Italy, its association with all-cause mortality, and whether measurement of serum C-reactive protein (CRP) and interleukin (IL)-6 affects this association. RESEARCH DESIGN AND METHODS: The baseline prevalence of metabolic syndrome, diagnosed according to the National Cholesterol Education Program (NCEP) criteria, and all-cause mortality at 4 years were recorded in an Italian population-based cohort (981 subjects, 55% women, aged 65-97 years). A Cox model adjusted for sociodemographic, lifestyle, and medical variables was used to investigate 1) whether metabolic syndrome was a predictor of mortality and 2) how the association was affected by baseline high CRP (>3 mg/l) and IL-6 (>1.33 pg/ml). RESULTS: Overall, metabolic syndrome prevalence was 27.2% [95% CI 24.0-30.5] and higher in women (33.3% [28.7-38.0]) than in men (19.6% [15.5-24.2]). During follow-up, 137 deaths occurred. Using the no metabolic syndrome/no high IL-6 group as the reference, mortality was not associated with the metabolic syndrome alone (multivariable-adjusted hazard ratio 1.24 [0.60-2.59]), only weakly associated with high IL-6 alone (1.66 [1.04-2.63]), but strongly associated with the concurrent presence of metabolic syndrome and high IL-6 (3.26 [2.00-5.33]). High CRP was not a mortality predictor (0.83 [0.58-1.20]) nor did it affect the association of the other variables with mortality. CONCLUSIONS: Metabolic syndrome by NCEP criteria is highly prevalent in the Italian elderly population. It is not itself associated with mortality but may improve the usefulness of IL-6 as a mortality predictor in older age.