Monika Paul-Samojedny

Functional Polymorphism in the Interleukin-6 and Interleukin-10 Genes in Patients with Paranoid Schizophrenia —A Case-Control Study

Schizophrenia is a multifactorial disease with changes in immunological system. Such changes are the result of cytokine-level disturbances connected with cytokine gene polymorphisms. However, research about cytokine gene polymorphisms in schizophrenia has been surprisingly limited and ambiguous. The aim of the study was to identify whether polymorphisms of interleukin (IL)-6 and IL-10 are risk factors for the development of paranoid schizophrenia in case-control study. IL-6 (−174G/C; rs 1800795) and IL-10 (−1082G/A; rs 1800896) promoter polymorphisms in patients with paranoid schizophrenia and healthy individuals were genotyped using polymerase chain reaction–restriction fragment length polymorphism method. Differences in IL-6 and IL-10 promoter haplotypes may play an important role in determining the transcription level for IL-6 and IL-10 genes in schizophrenic patients. The presence of allele C at position −174 of IL-6 promoter sequence may correlate with increasing risk of paranoid schizophrenia in the Polish population, but research on a broadened group of people is needed. The presence of allele G at position −1082 of IL-10 promoter sequence correlates with increasing risk of paranoid schizophrenia in the Polish population. The coexistence of genotype GG at position −1082 of IL-10 promoter sequence and genotype GC at position −174 of IL-6 promoter sequence correlates with increasing risk of paranoid schizophrenia in the Polish population.

Interleukin-1beta Promoter (−31T/C and −511C/T) Polymorphisms in Major Recurrent Depression

To elucidate a genetic predisposition to major depressive disorder, we investigated two polymorphisms (−31T/C and −511C/T) in the interleukin-1beta promoter region in patients who suffered from major recurrent depression. The aim of the current work was to compare alleles and genotype layout between patients with major recurrent depression and healthy people. We would like to indicate such combination of genotypes which corresponds with major recurrent depression. Correlations between genotypes for analyzed polymorphisms and number of episodes, number of points in Hamilton Depression Rating Scale, and age of onset were investigated as well. The study group consisted of 94 patients diagnosed with major recurrent depression. The control group included 206 healthy individuals. Both groups involved representatives of Caucasian population. Genotyping of polymorphisms was performed by using PCR-RFLP technique. A specific haplotype, composed of the C allele at −31 and the T allele at −511, has a tendency to have a statistically significant difference (p = 0.064) between patients and control group. Correspondence analysis revealed that genotype T/T at −31 and genotype C/C at −511 are associated with major recurrent depression. No association was found between genotypes for studied polymorphic sites and number of episodes, number of points in Hamilton Depression Rating Scale, and age of onset.

Imipramine and fluoxetine inhibit LPS-induced activation and affect morphology of microglial cells in the rat glial culture

BACKGROUND Recent evidence has suggested that antidepressants evoke neuroprotective and immunomodulatory effects in the brain, partly at least, by inhibiting glia activation. This study has been conducted on the lipopolysaccharide (LPS)-stimulated primary rat mixed glial cell culture in order to better recognize the influence of imipramine (a tricyclic antidepressant) and fluoxetine (a selective serotonin reuptake inhibitor) on the important balance between pro- and anti-inflammatory cytokines produced by the glial cells. Moreover, microscopic observations were made to describe the morphological alterations in the studied cell cultures exposed to the drugs. METHODS The effect of both antidepressants on TNF-α, IL-1β and IL-10 levels was determined by ELISA. The mRNA levels of mentioned cytokines were evaluated by qRT-PCR assay. Moreover, drug influence on the LPS-stimulated level of NF-κB p65 subunit in nuclear fraction was determined by the colorimetric transcription factor assay. RESULTS After LPS-stimulation both drugs decreased concentration of TNF-α and IL-1β in culture medium and expression of TNF-α and IL-1β mRNAs in cellular extracts. They also diminished the LPS-induced nuclear translocation of NF-κB p65 subunit. In contrast, imipramine and fluoxetine induced a few-fold weaker suppressing effect on the levels of IL-10. Parallelly to the inhibition of the LPS-induced inflammatory response, the antidepressants prevented the morphological alterations of cells elicited by LPS. Moreover, in unstimulated cultures imipramine but not fluoxetine caused transformation of microglia cells into cells with neuron-like morphology. CONCLUSIONS Imipramine and fluoxetine, by modulating glia activation, may exert anti-inflammatory effects in the CNS. It also seems that microglia cells are important target particularly for imipramine.

Association of interleukin 2 (IL-2), interleukin 6 (IL-6), and TNF-alpha (TNFα) gene polymorphisms with paranoid schizophrenia in a Polish population.

Numerous reports have brought attention to the potential role of cytokines in schizophrenia. The aim of the study was to determine whether polymorphisms of IL-2, IL-6, and TNFα genes are risk factors for development of paranoid schizophrenia in a Polish population. Promoter polymorphisms of IL-6 (rs1800795), TNFα (rs1800629), and IL-2 (rs2069762) genes in patients (N=115) and controls (N=135) were genotyped by PCR-RFLP and AS-PCR methods, respectively. Genotype TT and allele T for IL-2 polymorphism, and genotype AA and allele A for TNFα polymorphism were found to be significantly associated with paranoid schizophrenia. Similarly, haplotypes CTA and GTA increased the risk (4.4 times and 5.9 times, respectively) of schizophrenia. To reveal associations between Positive and Negative Symptom Scale subscales and age at onset of schizophrenia, the authors used a novel method called Grade Correspondence Analysis. This analysis revealed that patients with early age at onset have higher scores on the Negative and General subscales of PANSS, and, in that group of patients, haplotype CTA was the most represented. As far as is known, this analysis was used for the first time with reference to genetic data.

BDNF val66met Polymorphism Is Associated With Age at Onset and Intensity of Symptoms of Paranoid Schizophrenia in a Polish Population

The brain-derived neurotrophic factor (BDNF) is one of the candidate genes for schizophrenia. There is evidence that val66met polymorphism may be involved in the pathophysiology of schizophrenia. The authors genotyped val66met (rs6265) polymorphism of the BDNF gene in 208 inpatients with paranoid schizophrenia and 254 control subjects in a Polish population. There was no association between val66met polymorphism and development of paranoid schizophrenia in either men or women. However, an association was found between this polymorphism and age at onset and psychopathology of paranoid schizophrenia. Men with the val/met genotype had an earlier age at onset, and the val/val genotype predisposed to more severe symptoms, particularly on the General Psychopathology Scale of the Positive and Negative Symptoms Scale (PANSS-G). The analysis of PANSS single items has shown that patients with the val/met genotype had higher scores on a hallucinatory behavior item than those with other genotypes.

Association study of interferon gamma (IFN-γ) +874T/A gene polymorphism in patients with paranoid schizophrenia.

Schizophrenia is a multifactorial disease with changes affecting the immune system. Dysregulation of the cytokine network in schizophrenia has been well documented. Such changes may occur due to disturbances in cytokine levels that are linked to polymorphisms of cytokine genes. However, research in the role of cytokine gene polymorphisms in schizophrenia has been surprisingly scanty. The aim of this study was to identify, in a case control study, whether polymorphism of IFN-γ gene is a risk factor for the development of paranoid schizophrenia. To the best of our knowledge, this is the first study that examines the association between the IFN-γ gene polymorphism and psychopathological symptoms in patients with paranoid schizophrenia. Polymorphism of IFN-γ (+874T/A, rs 62559044) in schizophrenic patients (n = 179), as well as healthy individuals (n = 196), both Polish residents, was genotyped using AS-PCR method. Of note, when analyzing the results, we took into consideration the gender of studied individuals. Surprisingly, a single-nucleotide polymorphism in the first intron of the IFN-γ gene was found to be associated with paranoid schizophrenia in males, but not in females. The presence of allele A at position +874 in the IFN-γ gene correlates with 1.66-fold higher risk of paranoid schizophrenia development in males. Differences in the genotypes may have an important role in determining the level of I gene transcription. Because other polymorphisms have been demonstrated to influence IFN-γ transcription, further analysis is necessary to clarify the role of this gene in the pathogenesis of paranoid schizophrenia.

Moclobemide exerts anti-inflammatory effect in lipopolysaccharide-activated primary mixed glial cell culture

An increasing body of evidence indicates that glial activation and neuroinflammation play an important role in the pathogenesis of psychiatric and neurodegenerative diseases. Activated glial cells secrete various cytokines that influence neurotransmission, hypothalamus–pituitary–adrenal axis activity, neuronal plasticity and neurogenesis. It has been suggested that alterations in cytokine networks are involved in the mechanism of action of antidepressant drugs. Until now, only a few studies demonstrated that some tricyclic antidepressants and selective serotonin reuptake inhibitors reduced production of pro-inflammatory cytokines in brain glia cells. We have investigated for the first time whether the antidepressant, moclobemide (a reversible selective inhibitor of monoamine oxidase-A) has an influence on pro-inflammatory cytokines [interleukin (IL)-1β and tumor necrosis factor (TNF)-α] and anti-inflammatory cytokine (IL-10) in primary rat mixed glial cell cultures stimulated by lipopolysaccharide (LPS). Our results showed that moclobemide used in a wide range of concentrations diminished LPS-stimulated IL-1β and TNF-α mRNAs expression in cellular extracts and remarkably reduced the levels of both pro-inflammatory cytokines in culture medium. In opposite to this, the drug had no influence on IL-10 mRNA and slightly reduced IL-10 concentration. Moreover, moclobemide decreased LPS-stimulated translocation of NFκB p65 subunit into cellular nuclei. These results suggest that moclobemide exerts anti-inflammatory effect in the central nervous system because it affects the balance between pro- and anti-inflammatory cytokines (IL-1β, TNF-α/IL-10) in primary mixed glial cell cultures.

Chronic social instability stress enhances vulnerability of BDNF response to LPS in the limbic structures of female rats: a protective role of antidepressants.

The aim of the present study was to estimate the influence of antidepressants given chronically on brain-derived neurotrophic factor (BDNF) alterations induced by lipopolysaccharide (LPS) in the amygdala and hippocampus of female rats subjected to chronic social instability stress (CSIS) for 29-30 days. CSIS was used as a paradigm known to be more stressful for females because stress induces affective disorders more frequently in women than men. An increased relative adrenal weight and a tendency towards the enhanced plasma corticosterone concentration were found in the stressed rats. Sucrose preference was not changed. On the last experimental day, the rats in the estrus phase were injected ip with LPS (1mg/kg). In the stressed rats, LPS administration decreased BDNF mRNA levels in both limbic structures. Desipramine (10mg/kg), fluoxetine (5mg/kg) or tianeptine (10mg/kg) given ip once daily reversed the effect of the combined stress and LPS, and tianeptine induced the strongest effects. These results indicate that chronic stress enhances vulnerability of BDNF response to deleterious influence of neuroinflammation in the examined limbic structures, what may account for its role in triggering neuropsychiatric diseases. The observed effect of antidepressants may be of significance for their therapeutic effects in the stress-induced affective disorders in females.

Knockdown of AKT3 (PKBγ) and PI3KCA Suppresses Cell Viability and Proliferation and Induces the Apoptosis of Glioblastoma Multiforme T98G Cells

Glioblastoma multiforme (GBM) is the most malignant and invasive human brain tumor that is difficult to treat and has a very poor prognosis. Thus, new therapeutic strategies that target GBM are urgently needed. The PI3K/AKT/PTEN signaling pathway is frequently deregulated in a wide range of cancers. The present study was designed to examine the inhibitory effect of AKT3 or PI3KCA siRNAs on GBM cell growth, viability, and proliferation.T98G cells were transfected with AKT3 and/or PI3KCA siRNAs. AKT3 and PI3KCA protein-positive cells were identified using FC and Western blotting. The influence of specific siRNAs on T98G cell viability, proliferation, cell cycle, and apoptosis was evaluated as well using FC. Alterations in the mRNA expression of AKT3, PI3KCA, and apoptosis-related genes were analyzed using QRT-PCR. Knockdown of AKT3 and/or PI3KCA genes in T98G cells led to a significant reduction in cell viability, the accumulation of subG1-phase cells and, a reduced fraction of cells in the S and G2/M phases. Additionally, statistically significant differences in the BAX/BCL-2 ratio and an increased percentage of apoptotic cells were found. The siRNA-induced AKT3 and PI3KCA mRNA knockdown may offer a novel therapeutic strategy to control the growth of human GBM cells.

Interleukin-1B promoter (-31T/C and -511C/T) polymorphisms in paranoid schizophrenia.

Department of Medical Genetics, Medical University of Silesia, Sosnowiec, Department of Psychiatry and Psychotherapy, Medical University of Silesia, Katowice and Department of Instrumental Analysis, Division of Statistics, Medical University of Silesia, Sosnowiec, Poland Correspondence to Paulina Borkowska, PhD, Department of Medical Genetics, Medical University of Silesia, Ostrogorska 30, 41-200 Sosnowiec, Poland Tel/fax: + 48 32 364 14 01; e-mail: paubor85@gmail.com