Sex-specific analysis in Behçet's disease reveals higher genetic risk in male patients.

OBJECTIVES: Behçet's disease tends to be more severe in men than women. This study was undertaken to investigate sex-specific genetic effects in Behçet's disease. METHODS: A total of 1762 male and 1216 female patients with Behçet's disease from six diverse populations were studied, with the majority of patients of Turkish origin. Genotyping was performed using an Infinium ImmunoArray-24 BeadChip, or extracted from available genotyping data. Following imputation and extensive quality control measures, genome-wide association analysis was performed comparing male to female patients in the Turkish cohort, followed by a meta-analysis of significant results in all six populations. In addition, a weighted genetic risk score for Behçet's disease was calculated and compared between male and female patients. RESULTS: Genetic association analysis comparing male to female patients with Behçet's disease from Turkey revealed an association with male sex in HLA-B/MICA within the HLA region with a GWAS level of significance (rs2848712, OR = 1.46, P = 1.22 × 10-8). Meta-analysis of the effect in rs2848712 across six populations confirmed these results. Genetic risk score for Behçet's disease was significantly higher in male compared to female patients from Turkey. Higher genetic risk for Behçet's disease was observed in male patients in HLA-B/MICA (rs116799036, OR = 1.45, P = 1.95 × 10-8), HLA-C (rs12525170, OR = 1.46, P = 5.66 × 10-7), and KLRC4 (rs2617170, OR = 1.20, P = 0.019). In contrast, IFNGR1 (rs4896243, OR = 0.86, P = 0.011) was shown to confer higher genetic risk in female patients. CONCLUSIONS: Male patients with Behçet's disease are characterized by higher genetic risk compared to female patients. This genetic difference, primarily derived from our Turkish cohort, is largely explained by risk within the HLA region. These data suggest that genetic factors might contribute to differences in disease presentation between men and women with Behçet's disease.

Plasma oxysterols in drug-free patients with schizophrenia.

Evidence from clinical, genetic, and medical studies has shown the neuronal developmental disorder aspect of schizophrenia (SZ). Whereas oxysterols are vital factors in neurodevelopment, it is still unknown whether they are involved in the pathophysiology of SZ. The current study aims to explore the profile of oxysterols in plasma, ratio to total cholesterol (Tchol) and the association with clinical factors in patients with SZ. Forty men diagnosed with SZ and forty healthy controls matched for age and sex were included in the study. The ratios of cholestane-3ß,5α,6ß-triol, 27-hydroxycholesterol (27-OHC) and Cholestanol to Tchol increased in the schizophrenic group compared to controls. However, levels of 24S-hydroxycholesterol (24-OHC) were not significantly different between patients and controls. For the SZ patients, the plasma 24-OHC levels were positively correlated with the positive and negative syndrome total scores (PANSS) but negatively correlated with the Montreal Cognitive Assessment scores (MOCA). Moreover, the ratio Cholestanol to Tchol was negatively correlated with MOCA scores and positively correlated with PANSS general. The binary logistic regression analysis revealed that the ratio Cholestane-3ß,5α,6ß-triol/TChol could be considered as an independent risk factor for SZ. On the other hand, the receiver's operating characteristics analysis corresponding to potential biomarkers on SZ showed Areas Under the Curve (AUCs) of 82.1%; 69.7% and 77.6% for the ratio of Cholestane-3ß,5α,6ß-triol/TChol, 27-OHC/TChol and Cholestanol/TChol respectively. The relevance of Cholestane-3ß,5α,6ß-triol, 27-OHC and Cholestanol assays as biomarkers of this disease deserves further investigation.

Selected plasma oxysterols as a potential multi-marker biosignature panel for Behçet's Disease.

Clinical, genetic, and medical evidence has shown the inflammatory vasculitis aspect of Behçet's Disease (BD). Whereas oxysterols are vital factors in inflammation and oxidative stress, it is still unknown whether they are involved in the pathophysiology of BD. The current study aims to explore the profile of oxysterols in plasma of BD patients. Thirty patients diagnosed with BD and forty healthy controls matched for age and gender were included. Results showed that the cholestane-3ß,5α,6ß-triol, 27-hydroxycholesterol (27-OHC) and cholestanol levels were higher in BD than controls. In addition, plasma levels of 7-ketocholesterol (7-KC) and 25-hydroxycholesterol (25-OHC) were lower in BD patient. However, levels of 24S-hydroxycholesterol (24-OHC) did not significantly differ. For BD patients, the plasma 7-KC level was negatively correlated with the BD activity index (BDAI) while 27-OHC was positively correlated with high-sensitivity C-reactive protein (hs-CRP) in patients with active course of the disease. According to ROC analysis, a remarkable increase in the area under the curve (AUC) with a higher sensitivity (Se) and specificity (Sp) for 7-KC, 25-OHC and 27-OHC combined markers was observed. The present study indicated that the identification of the predictive value of these three-selected biomarkers related to oxidative stress and inflammation in patients should lead to a better identification of the etiological mechanism of BD.

Predictive value of oxidative stress biomarkers in drug-free patients with bipolar disorder.

OBJECTIVE: Oxidative stress is one of the primary etiological mechanisms of bipolar disorder (BD). METHODS: The present study was conducted over a period of 24 months on Tunisian on 34 drug­free male patients with BD (mean age: 34.5 years) and 101 age and gender matched controls (mean age: 34.20 years) were enrolled in the study. RESULTS: Plasma reduced glutathione (GSH) and total thiols levels were significantly decreased in patients compared to controls (respectively p < .001; p = .009). In addition, malondialdehyde (MDA), advanced oxidation protein products (AOPP), protein carbonyls (PC) and homocysteine (Hcys) concentrations and glutathione peroxidase (GSH-Px) activity were significantly increased in patients compared to controls (p = .002; p < .001; p = .001; p < .001 and p = .016, respectively). The binary logistic regression analysis revealed that MDA, AOPP and Hcys could be considered as independent risk factors for BD. When using CombiROC analysis, a remarkable increase in the area under the curve (AUC) with higher sensitivity (Se) and specificity (Sp) for MDA, AOPP, PC, GSH-Px and Hcys combined markers was observed. CONCLUSIONS: Overall, the identification of the predictive value of these five selected biomarkers related to oxidative stress in drug free patients should lead to a better identification of the etiological mechanism of BD.

Plasma oxysterols: Altered level of plasma 24-hydroxycholesterol in patients with bipolar disorder.

Cholesterol and its oxygenated metabolites, including oxysterols, are intensively investigated as potential players in the pathophysiology of brain disorders. Altered oxysterol levels have been described in patients with numerous neuropsychiatric disorders. Recent studies have shown that Bipolar disorder (BD) is associated with the disruption of cholesterol metabolism. The present study was aimed at investigating the profile of oxysterols in plasma, their ratio to total cholesterol and their association with clinical parameters in patients with BD. Thirty three men diagnosed with BD and forty healthy controls matched for age and sex were included in the study. Oxysterol levels were measured by isotope-dilution ultra-performance liquid chromatography-tandem mass spectrometry. Significantly higher levels were observed for cholestane-3ß,5α,6ß-triol, 27-hydroxycholesterol (27-OHC) and Cholestanol in patients with BD. The concentration of 24-hydroxycholesterol (24-OHC) was significantly lower in patients compared to controls. 24-OHC was also negatively correlated to MAS subscale score (r =-0.343; p = 0.049). In patients, 24-OHC was inversely correlated with age (r = -0.240; p = 0.045). Multivariate analysis found that BD acute decompensation was independently related to the rise in plasma 24-OHC (p = 0.002; OR = 0.966, 95 % CI [0.945 - 0.987]). However, the 24-OHC assay relevance as a biomarker of this disease deserves further investigation in other studies.

Genetic Association of a Gain-of-Function IFNGR1 Polymorphism and the Intergenic Region LNCAROD/DKK1 With Behçet's Disease.

OBJECTIVE: Behçet's disease is a complex systemic inflammatory vasculitis of incompletely understood etiology. This study was undertaken to investigate genetic associations with Behçet's disease in a diverse multiethnic population. METHODS: A total of 9,444 patients and controls from 7 different populations were included in this study. Genotyping was performed using an Infinium ImmunoArray-24 v.1.0 or v.2.0 BeadChip. Analysis of expression data from stimulated monocytes, and epigenetic and chromatin interaction analyses were performed. RESULTS: We identified 2 novel genetic susceptibility loci for Behçet's disease, including a risk locus in IFNGR1 (rs4896243) (odds ratio [OR] 1.25; P = 2.42 × 10-9 ) and within the intergenic region LNCAROD/DKK1 (rs1660760) (OR 0.78; P = 2.75 × 10-8 ). The risk variants in IFNGR1 significantly increased IFNGR1 messenger RNA expression in lipopolysaccharide-stimulated monocytes. In addition, our results replicated the association (P < 5 × 10-8 ) of 6 previously identified susceptibility loci in Behçet's disease: IL10, IL23R, IL12A-AS1, CCR3, ADO, and LACC1, reinforcing the notion that these loci are strong genetic factors in Behçet's disease shared across ancestries. We also identified >30 genetic susceptibility loci with a suggestive level of association (P < 5 × 10-5 ), which will require replication. Finally, functional annotation of genetic susceptibility loci in Behçet's disease revealed their possible regulatory roles and suggested potential causal genes and molecular mechanisms that could be further investigated. CONCLUSION: We performed the largest genetic association study in Behçet's disease to date. Our findings reveal novel putative functional variants associated with the disease and replicate and extend the genetic associations in other loci across multiple ancestries.

Predictive value of oxidative stress biomarkers in drug­free patients with schizophrenia and schizo-affective disorder.

Several studies have suggested that oxidative stress may represent one of the primary etiological mechanisms of schizophrenia (SZ) and schizoaffective disorder (SAD) which can be targeted by therapeutic intervention. The present study was conducted over a period of 24 months, between June 2016 and June 2018. All enrolled subjects were Tunisian, forty five drug­free male patients with SZ (mean age: 37.6 years), twenty one drug­free male patients with SAD (mean age: 28.8 years) and hundred and one age and gender matched controls (mean age: 34.2 years) were enrolled in the study. Plasma reduced glutathione (GSH) and Total thiols levels were significantly decreased in patients compared to controls (respectively p<0.001; p=0.050). In addition, malondialdehyde (MDA), advanced oxidation protein products (AOPP) and protein carbonyls (PC) concentrations and glutathione peroxidase (GSH-Px) activity were significantly increased in patients compared to controls (p<0.001; p<0.001; p<0.001 and p=0.003 respectively). The binary logistic regression analysis revealed that MDA, AOPP, PC and GSH-Px could be considered as independent risk factors for SZ and SAD. When using ROC analysis, a remarkable increase in the area under the curve (AUC) with higher sensitivity (Se) and specificity (Sp) for MDA, AOPP, PC and GSH-Px combined markers was observed. The present study indicated that the identification of the predictive value of this four-selected biomarkers related to oxidative stress in drug free patients should lead to a better identification of the etiological mechanism of SZ or SAD.

[Bipolar disorder vulnerability: The vitamin D path]. / Vulnérabilité au Trouble Bipolaire: La Piste de la Vitamine D.

OBJECTIVES: Bipolar disorder (BD) etiopathogenesis is still not well elucidated. It has recently been proven that 25-hydroxy vitamin D (25OHD) has an anti-inflammatory and neuroprotective role. Our objectives were to measure 25OHD plasma levels in patients with BD in acute decompensation and compare them with patients with schizophrenia (SCZ) or schizoaffective disorder (SAD) and with healthy controls. METHODS: This is a cross-sectional case-control study including male inpatients with a decompensation of their disease who were diagnosed with BD, SCZ or SAD according to DSM-5 criterias. The control group was constituted by unrelated healthy subjects, age-and-sex matched. RESULTS: The 25OHD level was significantly higher only in patients with BD compared to controls. 25OHD was also positively correlated to the PANSS scale (r = 0.282, p < 0.001) and to different MOCA scores (r = 0.326, p = 0.006) as well as aspects related to abstraction, attention and memory capacity. Multivariate analysis found that BD acute decompensation was independently related to the rise in plasma 25OHD (p = 0.012; OR =1.157, [1.032 -1.297]). CONCLUSION: Our study shows that BD acute decompensation is associated with the rise in plasma 25OHD synthesis. However, the vitamin D dosage relevance as a biomarker of this disease warrants a verification in other studies.

OBJECTIFS: L'étiopathogénie du trouble bipolaire (TB) demeure non encore bien élucidée. Récemment, il a été prouvé que la 25-hydroxy-vitamine D(25OHD) a un rôle anti-inflammatoire et neuroprotecteur. Nos objectifs étaient de mesurer les concentrations plasmatiques de la 25OHD chez des patients atteints de TB en décompensation aigue et de les comparer à celles de patients souffrant de schizophrénie (SCZ) ou de trouble schizo-affectif (TSA) et à celles de témoins sains. MÉTHODES: Il s'agissait d'une étude transversale de type cas-témoins qui a inclus des patients de sexe masculin hospitalisés pour une décompensation de leur maladie et chez qui les diagnostics de TB, SCZ, ou de TSA ont été retenus selon les critères du (DSM-5). Le groupe témoin a été constitué de sujets sains non apparentés, appariés selon l'age et le sexe. RÉSULTATS: La concentration de la 25OHD était significativement plus élevée uniquement chez les patients atteints de TB par rapport aux témoins. la 25OHD était aussi corrélée positivement à l'échelle PANSS (r = 0.282, p < 0.001) et aux différents scores de l'échelle MOCA (r = 0.326, p = 0.006) ainsi qu'aux dimensions concernant la capacité d'abstraction, d'attention et la mémoire . A l'analyse multivariée, la décompensation aigue du TB était liée de manière indépendante à l'élévation de la 25OHD plasmatique (p = 0.012; OR = 1.157, [1.032 -1.297]). CONCLUSION: Notre étude a montré que la décompensation aigue des TB était associée à une élévation de la synthèse de la 25OHD plasmatique. Toutefois, la pertinence du dosage de la vitamine D comme biomarqueur de cette maladie mérite d'être vérifiée par d'autres études.

Plasma Saturated and Monounsaturated Fatty Acids in Behçet's Disease.

BACKGROUND: Fatty Acid (FA) composition of serum has been associated with many markers of inflammation. In this study, we tried to examine plasma Saturated Fatty Acid (SFA) and Monounsaturated Fatty Acid (MUFA) composition in Behçet's Disease (BD) patients. The associations between the circulating FA levels and some markers of inflammation have also been investigated. METHODS: This study is a cross-sectional one. In fact, a total of 101 BD patients and healthy controls group of 99 subjects are enrolled. Gas Chromatograph equipped with a Capillary Split/Splitless Injector and flame ionization detector was used to analyze the plasma SFA and MUFA compositions. The high sensitivity C-Reactive Protein (hsCRP) and fibrinogen levels were measured using standard techniques. RESULTS: BD patients had significantly higher proportions of Mystiric Acid (MA), Palmitic Acid (PAM), Palmitoleic Acid (POA) and Stearoyl-CoA Desaturase (SCD)-16, compared to controls.The results revealed that patients with severe involvements had high levels of POA and total MUFA associated with higher SCD-16 activity compared to those with minor ones. The receiver operator characteristic curve analysis revealed that POA could well discriminate BD patients with severe clinical manifestations. In the bivariate analysis, hsCRP was found to be positively correlated with total SAFA and POA elongase activity index but negatively correlated with SCD-18 activity index. The STA, POA, elongase and SCD-16 activity index are correlated with fibrinogen. On the other hand, the multivariate analysis showed that POA remained associated with higher levels of hsCRP. CONCLUSION: Unfavourable plasma SFA and MUFA profile were reported in BD patients. POA, which is associated with higher plasma hsCRP level, may play a role in the pathogenesis of BD.

Association of hyperhomocysteinemia with genetic variants in key enzymes of homocysteine metabolism and methotrexate toxicity in rheumatoid arthritis patients.

OBJECTIVES: The study investigated the association between plasma homocysteine, folate and vitamin B12 with 5,10 methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), thymidylate synthase (TYMS 2R â†’ 3R) and methionine synthase (MTR A2756G) polymorphisms and methotrexate (MTX) treatment and toxicity in Tunisian Rheumatoid arthritis (RA) patients. METHODS: A total of 185 patients with RA were included. Homocysteine (Hcy) was assessed by fluorescence polarization immunoassay, and folate and vitamin B12 were measured by chemiluminescence immunoassays. The genetic polymorphisms were analyzed by PCR or PCR-RFLP. Hyperhomocysteinemia (HHC) was considered for Hcy > 15 µmol/L. RESULTS: MTHFR C677T polymorphism was associated with HHC in RA patients (multi-adjusted OR, 95% CI 2.18, [1.07-4.57]; p = 0.031). No association was detected with the remaining polymorphisms. Plasma Hcy, folate, and vitamin B12 did not differ according to each polymorphism, or with MTX treatment or toxicity. However, HHC was more prevalent in patients with than those without MTX toxicity (32.7 vs. 16.7%; p = 0.035). CONCLUSIONS: The MTHFR 677TT genotype is an independent risk factor for HHC in Tunisians RA patients. HHC could be a useful marker of MTX toxicity in RA patients.

Determination of the CCR5∆32 frequency in Emiratis and Tunisians and the screening of the CCR5 gene for novel alleles in Emiratis.

BACKGROUND: The chemokine receptor components play crucial roles in the immune system and some of them serve as co-receptors for the HIV virus. Several studies have documented that variants in chemokine receptors are correlated with susceptibility and resistance to infection with HIV virus. For example, mutations in the chemokine receptor 5 gene (CCR5) resulting in loss-of-function (such as the homozygous CCR5∆32) confer high degree of resistance to HIV infection. Heterozygotes for these variants exhibit slow progression to AIDS. The prevalence of CCR5 polymorphisms varies among ethnic and geographical groups. For example, the CCR5∆32 variant is present in 10-15% of north Europeans but is rarely encountered among Africans. This study aims to identify the prevalence of some CCR5 variants in two geographically distant Arab populations (namely Emiratis and Tunisians). METHODOLOGY: The prevalence of CCR5 gene variants including CCR5∆32, FS299, C101X, A29S and C178R has been determined using PCR and direct DNA sequencing. A total of 403 unrelated healthy individuals (253 Emiratis and 150 Tunisians) were genotyped for the CCR5∆32 variant using PCR amplification and gel electrophoresis. In addition, 200 Emiratis have been screened for other SNPs using Sanger DNA sequencing. RESULTS: Among Emiratis, the allele frequency of the CCR5∆32 variant has been found to be 0.002. In addition, two variants L55Q and A159 were found at a frequency of 0.002. Moreover, the prevalence of the CCR5∆32 variant in Tunisians was estimated to be 0.013 which is relatively higher than its frequency in Emiratis but lower than Europeans. CONCLUSION: We conclude that the allele frequency of the most critical CCR5 polymorphism (∆32) is extremely low among Emiratis compared to other Arabs and North Europeans. In addition, very low allele frequencies of other CCR5 polymorphisms have been detected among Emiratis.

Intima-media thickness of carotid artery in patients with Behçet's disease.

BACKGROUND AND AIMS: In this study we investigated the carotid intima-media thickness (cIMT) in Tunisian patients with Behçet's disease (BD), and we evaluated the relationship between traditional and nontraditional cardiovascular risk factors, disease manifestations, disease severity, use of immunosuppressive agents and cIMT in patients with BD. METHODS: Fifty patients with BD were individually matched to 50 control subjects on the basis of age, gender and traditional cardiovascular risk factors. Subjects with diabetes mellitus, evidence of myocardial infarction or cerebrovascular disease were excluded from the study. Patients with arterial involvement were also excluded. We measured serum high-sensitivity C-reactive protein (hsCRP), fibrinogen, creatinine levels and lipid profile. We also measured serum vitamin B12, folate, total plasma homocysteine levels, and HOMA-IR values. We used B-mode ultrasonography to assess the cIMT. RESULTS: cIMT in the BD group was significantly higher than in the control group (0.658 ± 0.112 mm vs. 0.581 ± 0.087 mm, respectively, p <10(-3)). The frequency of plaques in the carotid arteries was similar between study groups. In univariate analyses, the cIMT of BD patients was correlated with age (r = 0.510, p <10(-3)), male gender (p = 0.032), and creatinine clearance (r = -0.421, p = 0.003). It was inversely correlated with HOMA-IR values and serum vitamin B12 level. cIMT values were independent of disease manifestations, disease duration, or corticoid therapy. In the multivariate analysis, only male gender and creatinine clearance remained significantly associated with cIMT. CONCLUSIONS: Our data indicate morphologic evidence of subclinical atherosclerosis in patients with BD. Increased arterial wall thickness was not associated with the disease duration, clinical manifestations and immunosuppressive therapy.

Atherogenic lipid profile in Behçet's disease: evidence of alteration of HDL subclasses.

BACKGROUND AND AIMS: Behçet's disease (BD) is an inflammatory vasculitis, most common in the Mediterranean area and Asia. Evidence for accelerated atherosclerosis in BD has been observed. The relationship between cardiovascular risk factors and accelerated atherosclerosis in patients with BD is still controversial. The aim of this study was to evaluate the lipid profile and to investigate the low-density lipoprotein (LDL) size and the distribution of high-density lipoprotein (HDL) subpopulations in BD patients. METHODS: Thirty six BD patients were compared to 36 healthy controls. Total cholesterol (TC), triglycerides (TG) and HDL-cholesterol (HDL-C) levels were measured using standard techniques. HDL subclasses and LDL-C size were estimated using polyacrylamide linear gradient gel electrophoresis. The LDL-C/HDL-C ratio was also calculated. High-sensitive C-reactive protein (hsCRP) level was measured by a turbidimetric method. Homocysteine (Hcy) level was determined using a liquid chromatography tandem mass spectrometry (LC/MS/MS). RESULTS: In BD patients, HDL-C levels as well as its subfraction levels were decreased (respectively, p <10(-6) and p <10(-3)). Percentage of HDL2 subpopulation was also decreased (p=0.02). HDL3 subfraction was significantly higher (p=0.02). The LDL-C/HDL-C ratio and CRP level were increased (respectively, p=10(-4) and p=0.003). TC was correlated with CRP. HDL-C and its subfractions were correlated with CRP and TG levels. HDL subparticle percentages were also correlated with age. CONCLUSIONS: Our findings of a reduction of HDL-C and HDL2 subpopulation and an increase HDL3 subclass and a higher LDL-C/HDL-C ratio may be considered as important predictors of cardiovascular events in BD patients.