PERIPHERAL 8-ISO-PGF2α AS A BIOMARKER IN BOSNIAN PATIENTS WITH ALZHEIMER’S DISEASE AND VASCULAR DEMENTIA

Background: Cerebrospinal levels of isoprostanes (IsoPs) have been established as biomarkers of oxidative stress in Alzheimer’s disease (AD) and vascular dementia (VD). The value of peripheral levels in the diagnostics of these diseases is less conclusive. The aim of this study was to determine serum 8-iso-prostaglandin-F2alpha (8-iso-PGF2α) levels in Bosnian AD and VD patients and to establish whether there is an association between 8-iso-PGF2α serum concentration and cognitive impairment (CI) in patients with dementia. Subjects and methods: Serum levels of 8-iso-PGF2α were measured by enzyme immunoassay method in AD (n=30) and VD patients (n=30) and control subjects (CG, n=30). The AD and VD group were further stratified according to the level of CI. Results: The serum 8-iso-PGF2α levels were significantly higher in the AD (74.00 pg/mL) and VD groups (38.00 pg/mL) compared to the CG (17.50 pg/mL). A significant difference in serum 8-iso-PGF2α levels between patients with moderate and severe CI was not established in either AD or VD. Conclusion: Serum 8-iso-PGF2α proved to be a good biomarker in AD and VD, however it cannot be recommended for the differentiation of moderate and severe CI

ASSOCIATION OF NEUROPEPTIDE S RECEPTOR 1 AND GLUTAMATE DECARBOXYLASE 1 GENE POLYMORPHISMS WITH POSTTRAUMATIC STRESS DISORDER

Background: Posttraumatic stress disorder (PTSD) is an anxiety disorder caused by highly traumatic experiences. The aim of this study was to investigate the influence of single nucleotide polymorphisms (SNPs) in the neuropeptide S receptor 1 (NPSR1) and the glutamate decarboxylase 1(GAD1) gene on PTSD and its psychopathological aspects among individuals affected by the Balkan wars during the 90s. Subjects and methods: This study was conducted as part of the South Eastern Europe (SEE) study on molecular mechanisms of PTSD. It comprised 719 participants (539 males), including those with current PTSD, remitted PTSD and healthy volunteers. Psychometric evaluation was performed using the Mini International Neuropsychiatric Interview (M.I.N.I.), the Clinician Administrated PTSD Scale (CAPS) andthe Brief Symptom Inventory (BSI). We examined NPSR1 single nucleotide polymorphism (SNP) rs324981 and GAD1 variant rs3749034 genotypes. Case-control analyses were carried out using logistical regression to determine genotype differences between all patients that had either current or remitted PTSD and control individuals. To analyse the influence of the analysed SNPs on PTSD severity, we performed linear regression analyses with CAPS and BSI within each of the two patient groups separately. All of the calculations were performed for additive allelic, recessive, dominant and genotypic models. Results: We observed a nominally significant association for the major allele (G) of GAD1 rs3749034 with an increased risk to develop PTSD in a case control analysis in the recessive model (P=0.0315, odds ratio=0.47, SE=0.35). In contrast, a nominally significant association of the minor allele (A) with higher CAPS scores was identified within the patient group with lifetime PTSD in the dominant model (P=0.0372, ????=6.29, SE=2.99). None of these results did withstand correction for multiple tests. No nominal significant results of GAD1 rs3749034 were found with regard to the intensity of psychological BSI symptoms. Case control analyses of NPSR1 rs324981 revealed a nominally significant higher risk for homozygous T allele carriers to develop PTSD (P=0.0452) in the recessive model. On the other hand, the T allele showed a nominally significant association with higher BSI scores in patients suffering from lifetime PTSD in the recessive model (P=0.0434). Again, these results were not significant anymore after correction for multiple tests. No associations of NPSR1 rs324981 and CAPS score was identified. Conclusion: The findings of this study provide some evidence that the NPSR1 and GAD1 polymorphisms might play a role in the development of war-related PTSD and its related psychological expressions. Further research is needed to elucidate the interactions of specific gene variants and environmental factors in the development of PTSD

ASSOCIATIONS BETWEEN POLYMORPHISMS IN THE SOLUTE CARRIER FAMILY 6 MEMBER 3 AND THE MYELIN BASIC PROTEIN GENE AND POSTTRAUMATIC STRESS DISORDER

Background: Previous research showed inconsistent results concerning a possible association between solute carrier family 6 member 3 (SLC6A3) gene polymorphisms and dopamine symptoms of posttraumatic stress disorder (PTSD). Several studies also indicate that the myelin basic protein (MBP) gene is of importance in the etiology of several psychiatric disorders. The aim of this study was to investigate the relation of distinct SLC6A3 and MBP gene polymorphisms with PTSD and whether SLC6A3 and MBP genotypes contribute to PTSD symptom severity. Subjects and methods: The study included 719 individuals who had experienced war trauma in the South Eastern Europe (SEE). Genotypes of variable number tandem repeat (VNTR) polymorphism within the SLC6A3 gene were assessed in 696 participants, and the single nucleotide polymorphism (SNP) rs12458282 located within the MBP gene region was genotyped in a total of 703 subjects. The Mini International Neuropsychiatric Interview, the Clinical Administrated PTSD Scale (CAPS) and Brief Symptom Inventory (BSI), were used for data collection. Results: No significant differences concerning the investigated SLC6A3 and MBP polymorphisms was identifiable between PTSD and non PTSD participants. Also we could not detect significant influence of these distinct SLC6A3 and MBP alleles on the severity of PTSD symptoms (CAPS) or BSI scores. However, the results of MBP rs12458282 within the patients with lifetime PTSD may point to a possible correlation of the major allele (T) with elevated CAPS scores. Conclusions: Our results do not support an association of the analysed SLC6A3 and MBP gene polymorphisms with PTSD in war traumatized individuals. We found that there is a possibility for a correlation of the T allele rs12458282 within the MBP gene with higher CAPS scores in lifetime PTSD patients which would need to be tested in a sample providing more statistical power

THE ASSOCIATION OF CATECHOL-O-METHYL-TRANSFERASE AND INTERLEUKIN 6 GENE POLYMORPHISMS WITH POSTTRAUMATIC STRESS DISORDER

Background: Posttraumatic stress disorder (PTSD) is a disorder that occurs in some people who have experienced a severe traumatic event. Several genetic studies suggest that gene encoding proteins of catechol O-methyl-transferase (COMT) may be relevant for the pathogenesis of PTSD. Some researchers suggested that the elevation of interleukin-6 (IL6) correlates with major depression and PTSD. The aim of this study was to investigate whether the single nucleotide polymorphisms COMT rs4680 (Val158Met) and IL6 rs1800795 are associated with PTSD and contribute to the severity of PTSD symptoms. Subjects and methods: This study comprised 747 participants that experienced war between 1991 and 1999 in the South Eastern Europe conflicts. COMT rs4680 (Val158Met) and IL6 rs1800795 genotypes were determined in 719 participants (369 with and 350 without PTSD). The Mini International Neuropsychiatric Interview (M.I.N.I.), the Clinician Administrated PTSD Scale (CAPS) questionnaire and the Brief Symptom Inventory (BSI) were used for data collection. Results: Regarding the COMT gene polymorphism, the results of the regression analyses for BSI total score were significant in the lifetime PTSD group in the dominant (P=0.031) and the additive allelic model (P=0.047). Regarding the IL6 gene, a significant difference was found for the recessive model predicting CAPS total score in the lifetime PTSD group (P=0.048), and indicated an association between the C allele and higher CAPS scores. n the allelic, genotypic and rezessive model, the results for BSI total score were significant in the lifetime PTSD group (P=0.033, P=0.028 and P=0.009), suggesting a correlation of the C allele with higher BSI scores Conclusion: Although our nominally significant results did not withstand correction for multiple tests they may support a relevance of the COMT (Val158Met) and IL6 rs1800795 polymorphism for aspects of PTSD in war traumatized individuals

THE ROLE OF TAQI DRD2 (RS1800497) AND DRD4 VNTR POLYMORPHISMS IN POSTTRAUMATIC STRESS DISORDER (PTSD)

Background: Posttraumatic stress disorder (PTSD) is a complex stress related disorder, that follows a severe traumatic experience, characterized with an intense sense of terror, fear, and helplessness. The aim of this study is to identify associations of genetic variations within candidate genes DRD2 and DRD4 with various PTSD related phenotypes. PTSD lifetime and PTSD current subjects were analyzed separately, each of them were analyzed in a Case/Control design, as well as regarding BSI and CAPS within cases only. Subjects and methods: 719 (487 male, 232 female) participants who had experienced war-related trauma between 1991 and 1999 in Bosnia and Hercegovina, Kosovo and Croatia were included in the study. Sociodemographic questionnaire, Clinician Administered PTSD Scale (CAPS) and the Brief Symptom Inventory (BSI) were used to collect clinical data. Results: The DRD2 rs1800497 variant and a variable number tandem repeat (VNTR) located in exon three of DRD4 were investigated for association with PTSD. In case control analyses we did not identify any significant associations. Within the PTSD current patients, we identified an association of DRD2 rs1800497 with BSI in the genotypic and the recessive model with the T allele as the risk allele. Conclusion: Our findings suggest that rs1800497 of DRD2 gene is involved in pathogenesis of PTSD

ROLE OF THE ALLELIC VARIATION IN THE 5-HYDROXYTRYPTAMINE RECEPTOR 1A (HTR1A) AND THE TRYPTOPHAN HYDROXYLASE 2 (TPH2) GENES IN THE DEVELOPMENT OF PTSD

Background: Post-traumatic stress disorder (PTSD) is a stress related disorder which can occur in an individual after exposure to a traumatic event. It most commonly co-occurs with depression. The two disorders share not only overlapping symptoms, but also genetic diathesis. The aim of this study was to investigate the potential role of single nucleotide polymorphisms (SNPs) of the two serotonergic candidate genes 5-hydroxytryptamine receptor 1A (HTR1A) and tryptophan hydroxylase 2 (TPH2) in the pathogenesis of PTSD and comorbid psychopathology. Subjects and methods: 719 (487 males, 232 females) participants who had experienced war-related trauma between 1991 and 1999 in Bosnia and Herzegovina, Kosovo and Croatia were included in the study. The Sociodemographic questionnaire, Mini International Neuropsychiatric Interview (M.I.N.I.), Clinician Administered PTSD Scale (CAPS) and Brief Symptom Inventory (BSI) were used to collect clinical data. The SNPs rs6295 (HTR1A), rs11178997 and rs1386494 (TPH2) were investigated for their association with PTSD and comorbid psychopathology. Results: A nominal significant association was found between the BSI total score in Lifetime PTSD with the SNP rs6295 of the HTR1A gene. The best result was seen in the dominant model (P=0.018), with the minor allele (C) being the risk allele. Several BSI subscores were also associated with the minor (C) allele in Lifetime PTSD. No association was found for the TPH2 SNPs rs11178997 and rs1386494 in relation to PTSD or comorbid psychopathology. Conclusions: Our findings suggest that rs6295 in the HTR1A gene may contribute to the psychopathology of PTSD

MOLECULAR MECHANISMS OF POSTTRAUMATIC STRESS DISORDER (PTSD) AS A BASIS FOR INDIVIDUALIZED AND PERSONALIZED THERAPY: RATIONALE, DESIGN AND METHODS OF THE SOUTH EASTERN EUROPE (SEE)-PTSD STUDY

Posttraumatic Stress Disorder (PTSD) is a major health problem in South Eastern Europe (SEE). Available treatment options are not efficient enough and the course is often chronic. Little is known about molecular mediators and moderators of pathogenesis and therapy. Genetic and epigenetic variation may be one central molecular mechanism. We therefore established a consortium combining clinical expertise on PTSD from SEE countries Bosnia-Herzegovina (Sarajevo, Tuzla and Mostar), Kosovo (Prishtina) and Croatia (Zagreb) with genetic and epigenetic competence from Germany (Würzburg) in 2011 within the framework of the DAAD (Deutscher Akademischer Austauschdienst)-funded Stability Pact for South Eastern Europe. After obtaining ethical votes and performing rater trainings as well as training in DNA extraction from EDTA blood between 2011 and 2013, we recruited 747 individuals who had experienced war-related trauma in the SEE conflicts between 1991 and 1999. 236 participants had current PTSD, 161 lifetime PTSD and 350 did not have and never had PTSD. Demographic and clinical data are currently merged together with genetic and epigenetic data in a single database to allow for a comprehensive analysis of the role of genetic and epigenetic variation in the pathogenesis and therapy of PTSD. Analyses will be done to a great degree by PhD students from participating SEE centers who in addition to participation in the project had an opportunity to take part in spring and summer schools of the DFG (Deutsche Forschungsgemeinschaft) funded Research Training Group (RTG) 1253 and thus meet PhD students from Germany and other countries We are confident that our project will not only contribute to a better understanding of genetic and epigenetic mechanisms of PTSD as a basis for future individualized and personalized therapies, but also to the academic development of South Eastern Europe

International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci.

The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations

Potential causal association between gut microbiome and posttraumatic stress disorder

Background: The causal effects of gut microbiome and the development of posttraumatic stress disorder (PTSD) are still unknown. This study aimed to clarify their potential causal association using mendelian randomization (MR). Methods: The summary-level statistics for gut microbiome were retrieved from a genome-wide association study (GWAS) of the MiBioGen consortium. As to PTSD, the Freeze 2 datasets were originated from the Psychiatric Genomics Consortium Posttraumatic Stress Disorder Working Group (PGC-PTSD), and the replicated datasets were obtained from FinnGen consortium. Single nucleotide polymorphisms meeting MR assumptions were selected as instrumental variables. The inverse variance weighting (IVW) method was employed as the main approach, supplemented by sensitivity analyses to evaluate potential pleiotropy and heterogeneity and ensure the robustness of the MR results. We also performed reverse MR analyses to explore PTSD’s causal effects on the relative abundances of specific features of the gut microbiome. Results: In Freeze 2 datasets from PGC-PTSD, eight bacterial traits revealed a potential causal association between gut microbiome and PTSD (IVW, all P < 0.05). In addition, Genus.Dorea and genus.Sellimonas were replicated in FinnGen datasets, in which eight bacterial traits revealed a potential causal association between gut microbiome and the occurrence of PTSD. The heterogeneity and pleiotropy analyses further supported the robustness of the IVW findings, providing additional evidence for their reliability. Conclusion: Our study provides the potential causal impact of gut microbiomes on the development of PTSD, shedding new light on the understanding of the dysfunctional gut-brain axis in this disorder. Our findings present novel evidence and call for investigations to confirm the association between their links, as well as to illuminate the underlying mechanisms

Potential causal association between gut microbiome and posttraumatic stress disorder

Funding Information: We thank the participants and working staff including the Psychiatric Genomics Consortium Posttraumatic Stress Disorder Working Group, the FinnGen consortium, and the MiBioGen consortium. Publisher Copyright: © 2024, The Author(s).Background: The causal effects of gut microbiome and the development of posttraumatic stress disorder (PTSD) are still unknown. This study aimed to clarify their potential causal association using mendelian randomization (MR). Methods: The summary-level statistics for gut microbiome were retrieved from a genome-wide association study (GWAS) of the MiBioGen consortium. As to PTSD, the Freeze 2 datasets were originated from the Psychiatric Genomics Consortium Posttraumatic Stress Disorder Working Group (PGC-PTSD), and the replicated datasets were obtained from FinnGen consortium. Single nucleotide polymorphisms meeting MR assumptions were selected as instrumental variables. The inverse variance weighting (IVW) method was employed as the main approach, supplemented by sensitivity analyses to evaluate potential pleiotropy and heterogeneity and ensure the robustness of the MR results. We also performed reverse MR analyses to explore PTSD’s causal effects on the relative abundances of specific features of the gut microbiome. Results: In Freeze 2 datasets from PGC-PTSD, eight bacterial traits revealed a potential causal association between gut microbiome and PTSD (IVW, all P < 0.05). In addition, Genus.Dorea and genus.Sellimonas were replicated in FinnGen datasets, in which eight bacterial traits revealed a potential causal association between gut microbiome and the occurrence of PTSD. The heterogeneity and pleiotropy analyses further supported the robustness of the IVW findings, providing additional evidence for their reliability. Conclusion: Our study provides the potential causal impact of gut microbiomes on the development of PTSD, shedding new light on the understanding of the dysfunctional gut-brain axis in this disorder. Our findings present novel evidence and call for investigations to confirm the association between their links, as well as to illuminate the underlying mechanisms.publishersversionpublishe