Aikaterini Zisaki

APOE epsilon‐4 allele and cytokine production in Alzheimer's disease

The APOE epsilon‐4 allele has consistently emerged as a susceptibility factor for Alzheimers disease (AD). Pro‐inflammatory cytokines are detectable at abnormal levels in AD, and are thought to play a pathophysiological role. Animal studies have shown dose‐dependent correlations between the number of APOE epsilon‐4 alleles and the levels of pro‐inflammatory cytokines. The aims of this study were to investigate the influence of APOE genotypes on TNF‐α, IL‐6, and IL‐1β secreted by peripheral blood mononuclear cells (PBMC) from human patients with AD and to analyze the correlation between cytokine production and AD clinical features.

Association of SORL1 Alleles with Late-Onset Alzheimer's Disease. Findings from the GIGAS_LOAD Study and Mega-Analysis

The pathophysiology of Alzheimers disease (AD) is influenced by sorting-protein related receptor (sorLa) that is less expressed in AD patients. The gene encoding sorLa (SORL1) has been investigated as a susceptibility factor for late-onset AD (LOAD) with conflicting results. Our objectives were to confirm the association between SORL1 SNPs and LOAD in two independent South-European centers and to perform a mega-analysis of published samples. We analyzed three SORL1 SNPs (intron 6: rs668387; rs689021; rs641120) from the Greece-Italy Genetic Association Study on lateonset AD (GIGAS_LOAD). Greek sample included 96 patients with LOAD (DSM-IV) and 120 unrelated controls. In Italy, a community-based sample is ongoing. 47 LOAD patients and 165 controls were recruited until study endpoint. These samples and previously published ones (Alzgene) were pooled as in a single study. A test for trend was used to analyze genotype association. In the GIGAS_LOAD sample no association was detected between SORL1 genotypes and LOAD. Conversely all SNPs were associated with LOAD in mega-analysis based on ordinal classification of genotypes (Armitages test: p < 0.001). Although our analysis of pooled samples has positive results for the association between SORL1 and AD, there is substantial heterogeneity across studies. Thus further examination into SORL1 SNPs and the population is necessary to determine the role of SORL1 in LOAD.

Vitamin B12 Levels in Alzheimer's Disease: Association with Clinical Features and Cytokine Production

Alzheimers disease (AD) has been associated with up-regulation of pro-inflammatory cytokines (e.g., specific gene variants for TNF-alpha; IL-6; IFN-gamma) and low plasma levels of cyanocobalamin (vitamin B12). Our goal was to relate B12 levels to AD symptoms and to expression of pro-inflammatory cytokines. Clinical manifestations were investigated for a case series of fifty-five outpatients using the MMSE, Neuropsychiatric Inventory (NPI) and Cornell Scale for Depression in Dementia (CDDS). Plasma B12 levels were measured by radioligand binding assay. Basal and PMA-stimulated levels of IFN-gamma, TNF-alpha, and IL-6 were measured by ELISPOT (PBMC culture supernatant). 47 patients were genotyped for APOE. Ten patients (18%) had their B12 levels below < 250 pg/ml. They did not statistically differ from those 45 who had normal levels in most demographic and clinical features; their MMSE scores were lower (14.7 vs 19.6 p=0.03) but not after adjustment for disease duration. A greater basal production of IL-6 was reported in patients who had low B12 levels compared to normal B12 subjects (1333 pg/ml vs 976 p< 0.01); this association was confirmed after controlling for age of onset and APOE genotype. In conclusion, low B12 level is associated with greater production of IL-6 in peripheral blood mononuclear cells. Further research is warranted to elucidate whether this neuroinflammatory effect of cobalamin is implicated in the pathophysiology of AD.

Depression and Social Phobia Secondary to Alcohol Dependence

Background: According to the self-medication hypothesis, individuals with depression and anxiety disorders use alcohol to control their symptoms and subsequently become dependent. Conversely, alcohol dependence disorder (ADD) can cause or exacerbate psychiatric disorders. This study analyzed the characteristics of depression and social phobia secondary to ADD. (1) What is their functional impact? (2) Are they independent or associated conditions? (3) Do they completely remit in abstinent individuals? (4) Is the remission of one disorder associated with the remission of the other disorder? Methods: Sixty-four inpatients with ADD were evaluated with depression and anxiety disorder scales upon admission to hospital and after 5 weeks of detoxification. Results: Baseline comparisons differentiated patients with a Hamilton Rating Scale for Depression (HDRS) score >35 (n = 50; 78%) from those with an HDRS score ≤35 by higher levels of generalized anxiety and lower global functioning. Patients with generalized social phobia [Leibowitz Social Anxiety Scale (LSAS) score >60: n = 20; 31.2%] were not distinguishable from those with an LSAS score ≤60 by depressive and anxiety disorder symptoms. In postdetoxification assessment, patients who remitted from depression (HDRS score <7: n = 35; 54.6%) had a lower generalized anxiety and marginally higher levels of hypochondriasis compared to nonremitter subjects (HDRS score ≧7). Patients who remitted from social phobia (LSAS score <30: n = 32; 50%) did not significantly differ from nonremitter subjects in depressive and anxiety disorder symptoms. Generalized anxiety (Hamilton Rating Scale for Anxiety) and hypochondriasis (Whiteley Index) were the significant predictors of global functioning (Global Assessment Scale). Conclusions: Depression and social phobia secondary to ADD are independent conditions that do not completely remit after cessation of drinking. Specific treatments are needed to reduce residual depressive and anxiety symptoms in abstinent alcoholics.

Interleukin-1 alpha and beta, TNF-alpha and HTTLPR gene variants study on alcohol toxicity and detoxification outcome.

Genetic factors may influence the liability to treatment outcome and medical complications in alcoholism. In the present study we investigated the IL-1A rs1800587, IL-1B rs3087258, TNF-alpha rs1799724 and the HTTLPR variants in a sample of 64 alcohol dependents and 47 relatives versus a set of clinical parameters and outcome measures. Alcohol dependents had a less favorable clinical profile compared to relatives (higher cholesterol, triglycerides, glucose, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, gamma-glutamyltransferase). After detoxification, all clinical indexes improved and hepatic enzyme levels were similar in alcohol dependents and relatives, except for the GGT that remained significantly higher in alcohol dependents. Alcoholic depressive and anxiety scores were significantly reduced after detoxification. IL-1A, IL-1B, TNF-alpha and HTTLPR variants were not associated with any baseline clinical index or change after detoxification. In our sample IL-1A, IL-1B, TNF-alpha and HTTLPR do not appear as liability factors for alcohol toxicity or detoxification outcome, however the small sample size may influence the observed results.

TPH2 gene variants and anxiety during alcohol detoxification outcome

Clinical outcome of alcoholism may be partly under genetic control. The serotonergic system is involved in alcohol intake, and it has been widely investigated in alcohol dependence. Recently, attention has been focused on the neuronal tryptophan hydroxylase 2 gene (TPH2). TPH2 variants have been consistently associated with anxiety-related traits; since anxiety is critical for alcohol dependence treatment, in the present paper we investigated 9 SNPs within the THP2 gene in anxiety symptoms during the detoxification procedure. The sample comprised 68 alcohol-dependent patients who where evaluated with the Hamilton Rating Scale for Anxiety, before and after the detoxification procedure. Other psychopathological indicators of outcome, such as depression and anxiety sub-features were also investigated. We did not observe a role for TPH2 variants in the efficacy of treatment in relieving anxiety and other psychopathological symptoms. However, a haplotype that included the promoter rs4570625 polymorphism (associated with anxiety-related traits in previous studies) showed an association with the severity of anxiety symptoms on admission. This preliminary finding, although obtained on a small sample, may provide further support for a role of the TPH2 gene in emotional behaviors. Furthermore, the present study suggests the possible functional significance of the promoter rs4570625 polymorphism. The present preliminary results are of interest in alcoholism, given that comorbidity with anxiety represents a critical problem in treatment settings and response to detoxification.

Impact of 5-HTTLPR polymorphism on alexithymia in alcoholic patients after detoxification treatment.

Alexithymia symptoms have been reported in individuals suffering from alcohol abuse and other substance use disorders (SUDs) (Thorberg et al., 2009; Malat et al., 2010). However, alexithymia does not seem to be a stable disorder in SUD patients; indeed, symptoms’ decline has been reported in some individuals after detoxification treatment (de Haan et al., 2012). A combination of genetic and environmental influences may contribute to individual differences in alexithymia (Baughman et al., 2011). Therefore, genetic factors may modulate the risk to develop alexithymia symptoms in SUD patients and the recovery from symptoms after detoxification. In a previous study, we investigated a set of genetic variants in detoxification outcome, taking into account also alexithymia (Serretti et al., 2006b). We observed a reduction of alexithymia symptoms after treatment but not dependently from genetic variants. In particular, reduction of alexithymia symptoms was not influenced by the biallelic length polymorphism within the promoter region of the serotonin transporter gene (5-HTTLPR long/short), a polymorphism that has received much interest in several psychopathologic dimensions,