Association between polymorphisms of TLR2-1-6 and bipolar disorder in a tunisian population.

BACKGROUND: Bipolar disorder (BD) is a complex neuropsychiatric disease that has been strongly linked to immune dysregulation. In particular, an abnormal inflammatory response mediated by toll-like receptor 2 - 1/6 (TLR2-1/6) was described in BD. Nevertheless, genetic factors' contribution is still unknown. Thus, we suggested that functional polymorphisms of TLR2, 1 and 6 could be involved in BD predisposition. METHODS AND RESULTS: TLR2, 1 and 6 polymorphisms were genotyped by PCR-RFLP in 292 controls and 131 patients from a Tunisian population. Polymorphisms and haplotype associations were explored in BD and binary logistic regression analysis was performed for more powerful associations. In dominant model, we found a significantly higher genotype and minor allele frequencies in healthy females compared to patients for TLR2-196-174Ins/Del (p = 0.04; OR = 0.3, p = 0.04; OR = 0.3, respectively) and for TLR6-S249P only with minor allele (p = 0.03; OR = 0.2). In contrast, TLR2-R677W CT + TT and T allele frequencies were significantly higher in BD (padjusted<10- 4; ORadjusted =46.6, p < 10- 4; OR = 6.3, respectively), specifically in females (CT + TT: 100%). Similarly, TLR1-R80T showed significantly increased GC + CC and C allele frequencies in patients compared to controls (padjusted=0.04; ORadjusted=4, p = 0.009; OR = 4.3, respectively). Moreover, haplotype investigation demonstrated that InsGTCGT (p < 10- 4, OR = 275) and delGCCGT (p = 0.03, OR = 18.5) were significantly overrepresented in BD patients compared to controls. CONCLUSIONS: We suggest that TLR2-196-174Ins/Del and TLR6-S249P could be protective factors of females against BD. However, TLR2-R677W and TLR1-R80T could be strongly associated with higher risk of BD. Interestingly, TLR2-R677W could be a genetic marker for BD in females. However, further studies with larger groups are needed to confirm these findings.

TLR4 Polymorphisms (T399I/D299G) Association with Schizophrenia and Bipolar Disorder in a Tunisian Population.

Immune dysregulation has been widely described in the pathophysiology of schizophrenia (SCZ) and bipolar disorder (BD). Particularly, TLR4-altered activation was proposed as one of the underlying processes of psychosis onset. Since TLR4 activation was altered by T399I and D299G polymorphisms, we hypothesized that those variants could present common genetic factors of SCZ and BD. A total of 293 healthy volunteers and 335 psychotic patients were genotyped using PCR-RFLP. Genotype, allele, and haplotype distribution between controls and patients were evaluated according to clinical parameters. Statistical analyses were adjusted by logistic regression. In dominant model, T399I CT + TT and allele frequency were significantly higher in controls compared to psychotic population (p = 0.004, p = 0.002, respectively), SCZ (p = 0.02, p = 0.01, respectively), and BD (p = 0.03, p = 0.02, respectively). Similarly, D299G AG + GG and allele frequency were significantly higher in controls compared to psychotic population (p = 0.04, p = 0.04, respectively) and SCZ (p = 0.04, p = 0.03, respectively). T399I CT + TT and T allele were overrepresented in controls compared to paranoid subgroup (Padjusted = 0.04, p = 0.04, respectively) and type I BD (p = 0.04). Moreover, T399I and D299G were less prevalent in SCZ late-onset age (p = 0.03, p = 0.02, respectively). TA haplotype was associated with protection from psychoses (p = 0.02) and particularly from schizophrenia (p = 0.04). In conclusion, TLR4 polymorphisms could present a preventive genetic background against psychoses onset in a Tunisian population. While T399I could be associated with protection against SCZ and BD, presenting an overlapping genetic factor between those psychoses, D299G was suggested to be associated with protection only from schizophrenia.

Eating disorder and anxiety during Covid19 pandemic: the Maghrebian experience.

The coronavirus pandemic is considered the worst-hit that the world had witnessed in the current century. The impact of the pandemic, especially during the lockdown, was not only diverse but also worldwide. The African continent, including the Maghreb, was no exception. The aim of this study was to assess the levels of anxiety and eating behaviors and their correlations in three Maghrebian countries following the official outbreak of the COVID19 pandemic. It is a cross-sectional study of 754 participants from Tunisia, Algeria and Morocco. It took place between 30 April and 2 July 2020. The survey showed that eating disorders represented 45.9% of the sample while 26.8% (202 participants) matched the anxiety criteria. Statistical significant factors for eating disorders were gender (p = 0.002; OR = 1.760), underweight (p = 0.021; OR = 0.306), anxiety (p = 0.001; OR = 0.470), bulimia (p = 0.000; OR = 0.794) and body dissatisfaction (p = 0.000; OR = 0.920). This rise goes along with other surveys in different parts of the world. These results can be explained by multiple reasons such as the 'food insecurity' mechanism, the excessive feeling of boredom and loneliness resulting from social distancing and the overwhelming overthinking about the onset of a serious economic crisis.

A Preventive Role of RANTES Genetic Variation against Undifferentiated Schizophrenia.

AIM: Due to conflicting data from relevant studies, evidence for chemokine alterations in the pathophysiology of schizophrenia (Scz) remains inconclusive. Thus, we aimed to investigate the impact of rs2107538, rs2280788, and rs2280789 polymorphisms in CCL5 gene, as well as rs333 within CCR5 gene and the development of Scz in a Tunisian cohort. METHODS: We performed a case-control study composed of 200 patients and 200 controls using RFLP-PCR. RESULTS: Among the analyzed polymorphisms, only rs2107538 imparted protection against Scz and more specifically to male sex. This protective effect remained valid for the undifferentiated form. Moreover, this SNP had an impact on patients' symptomatology. When focusing on haplotypes, we noticed that the rs2107538-rs2280788-rs2280789 ACT genetic combination, with only one mutated allele rs2107538A, displayed reduced frequency in both Scz (as a whole group) and undifferentiated subtype. The haplotype distribution profile implies that the A allele at rs2107538 could induce a protective effect by increasing RANTES production. CONCLUSION: Additional independent analyses are required to corroborate these findings and elucidate the functional implications of the discovered preventing genotypes and haplotypes in Scz.

Clinical and genetic influencing factors on clozapine pharmacokinetics in Tunisian schizophrenic patients.

Clozapine (Clz) is an atypical antipsychotic, which its pharmacokinetics can be influenced by several factors. The CYP1A2 and CYP2C19, major enzymes implicated in Clz metabolism, present an interethnic variation on their activity caused by single nucleotide polymorphisms (SNPs). The present study investigated the influence of genetic and nongenetic factors on Clz pharmacokinetics in a southern Mediterranean population. We included adult Tunisian schizophrenic patients having received Clz and undergone a therapeutic drug monitoring (TDM) of Clz by morning C0 monitoring. The genomic DNA was extracted using a salting-out procedure. CYP1A2*1F (rs762551;-163C>A), CYP1A2*1C (rs2069514;-3860 G>A) and CYP 2C19*2 (rs4244285; 681G>A) was analyzed using PCR-RFLP. Fifty-one patients were enrolled in the study. The mutant allele (CYP1A2*1F) was the most frequently detected (58.8%). For CYP1A2*1F, Clz dose-normalized (C0/D ratio) was as high as 1.28 ± 0.37 in CC versus 0.67 ± 0.32 ng mL-1 per mg day-1 in AA group (p < 0.001). The influence of genetic (CYP1A2*1F, CYP1A2*1C and CYP2C19*2) and nongenetic parameters (age, weight, gender, tobacco, coffee, and alcohol consumption) on the variation of the Clz C0/D ratio was investigated. Only the CYP1A2*1 F polymorphism correlates significantly with the Clz C0/D variation and could explain 24% of its variability. Our data support a critical role of the CYP1A2 -163C>A on the variation of Clz exposure in Tunisian schizophrenic patients. Considering its narrow therapeutic range, CYP1A2 genotyping combined with TDM of Clz may improve efficacy and safety of this drug. Further studies are needed to investigate this issue.

Lipid profile in schizophrenia: case control study.

INTRODUCTION: Cardiovascular diseases are common co morbidities of schizophrenia and constitute the main factors of high mortality in this pathology. Cardiovascular damages are favored by some risk factors, of which one of the most important is dyslipidemia. In this context, a study of lipid profile in schizophrenia is interesting.  The aims of this study were to compare the lipid profile of patients with schizophrenia to healthy controls and to investigate the associations between lipid parameters and demographics, clinical and treatment characteristics of the patients. METHODS: We conducted a case-control study between April 2013 and March 2014 on 78 patients with schizophrenia and 68 healthy subjects who benefited from the dosage of four serum lipid parameters: total cholesterol (TC), triglycerides (TG), High-density lipoprotein Cholesterol (HDL-C) and Low-density lipoprotein cholesterol (LDL-C). For the socio-demographic and clinical assessments, we used an information sheet and the following psychometric scales: PANSS (Positive And Negative Syndrome Scale), CGI (Clinical Global Impressions), GAF (Global Assessment Functionning) and the Calgary scale for depression. RESULTS: The comparative study showed that serum concentrations of TC and LDL-C were significantly higher for patients compared to healthy controls respectively with (t=2,83 ; p=0,008) and             (t=9,35; p<0,001), the cholesterol ratio (TC / HDL-C) was also significantly higher for patients           (t=2,23; p=0,033). The patients had significantly higher prevalence of hypercholesterolemia              (OR = 2.96) and low density hyperlipoproteinemia (OR = 18.79). The analytical study in the population of patients showed that the age ≥35 year-old, male gender and alcohol consumption were associated with disturbances in lipid parameters. Cannabis consumption was associated with significantly lower concentrations in TG. Concerning clinical features, paranoid schizophrenia was associated with less dyslipidemia unlike the depressive dimension assessed by the Calgary scale. There was a negative correlation between plasmatic TG concentrations and doses of antipsychotics. CONCLUSION: The vast majority of the literature confirms that patients with schizophrenia are at greater risk of dyslipidemia. This high risk appears to be more important with the consumption of alcohol and tobacco. It seems also that age and masculine gender are dyslipidemia risk factors for schizophrenic patients. The paranoid type of schizophrenia and positive symptoms seem to be associated with less dyslipidemia while depressive symptoms worsen lipid parameters. It then follows that, clinical and regular monitoring of lipid profile, lifestyle recommendations (smoking cessation, exercise and balanced diet) and appropriate therapeutic choices could help reduce morbidity and mortality among patients with schizophrenia. A special focus should be accorded to patients with high negative and depression symptoms.

Association of the IFN-γ (+874A/T) Genetic Polymorphism with Paranoid Schizophrenia in Tunisian Population.

Since growing evidence suggests a significant role of chronic low-grade inflammation in the physiopathology of schizophrenia, we have hypothesized that functional genetic variant of the IFN gamma (IFN-γ; +874A/T; rs2430561) gene may be involved in the predisposition to schizophrenia. This research is based on a case-control study which aims to identify whether polymorphism of the IFN-γ gene is a risk factor for the development of schizophrenia. The RFLP-PCR genotyping of the IFN-γ gene was conducted on a Tunisian population composed of 218 patients and 162 controls. The IFN-γ (+874A/T) polymorphism analysis showed higher frequencies of minor homozygous genotype (TT) and allele (T) in all patients compared with controls (11.5 vs. 4.9%; p = 0.03, OR = 2.64 and 30.7 vs. 24.1%, p = 0.04, OR = 1.4, respectively). This correlation was confirmed for male but not for female patients. Also, the T allele was significantly more common among patients with paranoid schizophrenia when compared with controls (25.8 vs. 4.9%, p = 0.0001; OR = 6.7). Using the binary regression analysis to eliminate confounding factors as age and sex, only this last association remained significant (p = 0.03; OR = 1.76, CI = 1.05-2.93). In conclusion, our results showed a significant association between +874A/T polymorphism of IFN-γ and paranoid schizophrenia, suggesting that this single nucleotide polymorphism (SNP) or another at proximity could predispose to paranoid schizophrenia. Since the minor allele of this polymorphism was correlated with an increased expression of their product, our study validates the hypothesis of excessive pro-inflammatory cytokine in the physiopathology of paranoid schizophrenia.

Neurological soft signs in Tunisian patients with first-episode psychosis and relation with cannabis use.

BACKGROUND: Neurological soft signs (NSS) are minor non-localizing neurological abnormalities that are conceptualized as neurodevelopmental markers that mediate the biological risk for psychosis. We aimed to explore the relationship between NSS and cannabis use, an environmental risk factor of psychosis. METHODS: This was a cross-sectional study in consecutively admitted patients hospitalized for first-episode psychosis. NSS were assessed by the NSS scale (23 items exploring motor coordination, motor integrative function, sensory integration, involuntary movements or posture, quality of lateralization). Presence of NSS was defined as a NSS scale total score ≥9.5. Cannabis use was ascertained with the cannabis subsection in the Composite International Diagnostic Interview. RESULTS: Among 61 first-episode psychosis patients (mean age = 28.9 ± 9.4 years; male = 86.9%, antipsychotic-naïve = 75.4%), the prevalence of current cannabis use was 14.8% (heavy use = 8.2%, occasional use = 6.6%). NSS were present in 83.6% of the sample (cannabis users = 66.7% versus cannabis non-users = 85.5%, p = 0.16). The mean total NSS score was 15.3 ± 6.7, with a significant lower total NSS score in cannabis users (11.2 ± 5.6 versus 16.0 ± 6.7, p = 0.048). Differences were strongest for the "motor coordination" (p = 0.06) and "involuntary movements" (p = 0.07) sub-scores. CONCLUSIONS: This study demonstrated a negative association between cannabis use and NSS, especially regarding motor discoordination. This finding supports the hypothesis that a strong environmental risk factor, such as cannabis, may contribute to the onset of psychosis even in the presence of lower biological and genetic vulnerability, as reflected indirectly by lower NSS scores. Nevertheless, additional studies are needed that explore this interaction further in larger samples and considering additional neurobiological and environmental risk factors.

Comparison of Mineral Contents in Three Different Tobacco Formulations.

We identified and quantified a variety of mineral elements in 18 tobacco samples purchased from a Tunisian market. In total, 25 mineral elements have been measured in cigarettes, water pipe tobacco, and smokeless tobacco using inductively coupled plasma-optical emission spectroscopy following microwave-assisted digestion. Statistical analyses were performed using SPSSTM, version 18.0. The lowest concentrations of all studied elements were observed in water pipe tobacco. Significantly higher concentrations of Al, Fe, Mg, Na, Ca, Cr, and Co were found in smokeless tobacco, while cigarettes brands contained the highest concentrations of K, Mn, Ni, Ba, and Sr. There was no significant difference between the mineral contents of local and foreign cigarettes and conventional and light cigarettes. Our findings demonstrated that local smokeless tobacco appears to be the most hazardous tobacco type. The concentration of minerals in light cigarettes was not significantly different from the concentration in conventional cigarettes.

IFNGR2 genetic polymorphism associated with sex-specific paranoid schizophrenia risk.

BACKGROUND: Considering current scientific evidence about the significant role of chronic low grade inflammation in the physiopathology of schizophrenia, it has been hypothesized that changes in pro-inflammatory cytokines such as interferon gamma may have a significant role in the predisposition to schizophrenia. AIM: This study focuses on identifying whether the functional polymorphism of interferon gamma receptor 2 (IFNGR2) is a risk factor for the development of schizophrenia. METHODS: This study was conducted by the RFLP-PCR on a Tunisian population composed of 225 patients with different sub-types of schizophrenia and 166 controls. RESULTS: The IFNGR2 (Q64R) polymorphism analysis showed higher frequencies of minor homozygous genotype (RR) and allele (R) in all patients compared to controls (21.8% vs 10.2%; p = .006, OR = 2.54) and (44% vs 34.9%; p = .01; OR = 1.46), respectively. This correlation was confirmed only for males. This study also noted a significant increase of the mutated homozygous (RR) genotype and (R) allele frequencies of IFNGR2 in paranoid schizophrenics compared to controls (31.4% vs 10.2%; p = .001; OR = 3.34 and 47.2% vs 34.9%; p = .009; OR = 1.66, respectively). This increase remains significant after using binary logistic regression to eliminate confounding factors such as age and sex. Additionally, carriers of RR genotype have significant lower scores on the Scale of Assessment of Positive (SAPS) and negative (SANS) symptoms comparatively to the carrier of the QQ + QR genotypes, suggesting that the R recessive allele carriers could have milder symptoms. CONCLUSION: The IFNGR2Q64R polymorphism is correlated with male sex and paranoid schizophrenia. It is suggested that a chronic neuroinflammation may predispose to the paranoid schizophrenia development in men.

The association between altered lipid profile and suicide attempt among Tunisian patients with schizophrenia.

BACKGROUND: There have been many studies on psychiatric disorders, but very little is known about the biology of suicide with schizophrenia. In the present study, we are looking for a possible connection between altered lipid profile and suicidal behavior in schizophrenic Tunisian patients. METHODS: Assay of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), and triglycerides (TG) has been done for 126 schizophrenic patients with and without suicide attempts and 131 healthy controls recruited in the University Hospital of Monastir. RESULTS: TC and LDL-c levels were significantly higher in schizophrenic patients compared to controls. TC was significantly lower in schizophrenic patients with suicide attempt compared to those without suicide attempt. Depending to the sonority of suicide attempt, TC was significantly lower in patients with recent suicide attempt compared to those with lifetime suicide attempt and without suicide attempt (p < 0.001), and no significant differences between TG, LDL-c, and HDL-c were noted. CONCLUSIONS: Results of this study showed that TC levels in schizophrenic patients after a recent suicide attempt are significantly lower than in patients without suicide attempt and with lifetime suicide attempts. TC can be one of biological markers defined suicidal risk for schizophrenic patients.

CT genotype of 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism is protector factor of major depressive disorder in the Tunisian population: a case control study.

BACKGROUND: Major depressive disorder (MDD) is a common psychiatric disorder with considerable mortality. Death from unnatural causes, largely suicidal or quasi-suicidal, has a particularly high risk for the functional disorders, especially depression and schizophrenia. One of the prospective risk factors for this disease is hyperhomocysteinemia and folate deficiency. The methylenetetrahydrofolate reductase (MTHFR) gene encodes for a 5-methylenetetrahydrofolate reductase involved in folate metabolism and neurotransmitter synthesis. The aim of this research is to study the association between the C677T polymorphism of MTHFR gene and depression in Tunisian population, to explore their relationship with clinical and therapeutic characteristics of this disease. And it may lead to discover a novel marker to identify a patient with a higher risk of development of depressive disorder to be. This marker can be used for better therapeutic management and prevent disease installation. METHODS: Our study included 208 depressive patients, 187 controls aged between 44.1 ± 13.5 and 38.9 ± 13.2 years, respectively. MTHFR gene polymorphisms were determined by PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). RESULTS: No significant difference was detected in the distribution of the genotype frequencies of MTHFR C677T polymorphisms (χ (2) = 5.443, df = 2, p = 0.066) between patients and controls. But when we study the risk of these genotypes, CT genotype is significantly more frequent in controls compared to patients, it may be a protection from depression (OR = 0.655, CI 95 % = 0.432-0.995, p = 0.047, OR* = 0.638, CI 95 %* = 0.415-0.983, p* = 0.04, before and after adjustment). Women, TT Genotype can increase four times the risk to be depressive. Addictive behavior seems to be associated with CT genotype and there was no significant association between clinical and therapeutic characteristics and this polymorphism. CONCLUSION: This paper is the first study to prove that CT genotype of MTHFR C677T polymorphism may protect from depression and TT genotype seems to be associated with women's depression. Further studies are required with other polymorphisms and biochemical factors that must be investigated to clarify the implication of MTHFR C677T polymorphism in the pathophysiology of depression.

C3 Polymorphism Influences Circulating Levels of C3, ASP and Lipids in Schizophrenic Patients.

Excessive activation of complement is associated with many diseases including schizophrenia. Investigation of C3 polymorphisms, circulating C3, cleavage product ASP/C3adesArg, and lipid metabolism. Cross-sectional analysis. C3 genotyping (CC vs GG for R102L) was performed on 434 Tunisian people consisting of 272 schizophrenic (SZ) patients and 162 control subjects. In a age- and gender-matched subgroups of the three genotypes (131 SZ and 112 NOR), plasma triglycerides, total cholesterol (C), LDL-C, HDL-C, ASP, and complement C3 were measured. C3 gene polymorphism influences BMI and plasma C3, ASP, triglyceride, total cholesterol, LDL-C and HDL-C among SZ patients (p < 0.05-0.0001), with increasing values demonstrated from CC (common form) to CG (heterozygote form) to GG (rare homozygote) forms. Significant correlations between plasma C3 and BMI, triglyceride, HDL-C and ASP (p < 0.05-0.0001) were observed, while ASP correlated with BMI and LDL-C (p = 0.005, p = 0.001, respectively) in SZ patients. Further, proportional conversion of C3 to ASP (%ASP/C3) also increased (p < 0.0001, GG>CG>CC). C3 polymorphisms and plasma C3, ASP and %ASP/C3 correlated with lipid parameters in this SZ population, suggesting that factors predisposing patients to schizophrenia are permissive for complement pathway activation and dyslipidemic influences.

[Prevalence of specific learning disorders in a cohort of children with school failure]. / Prévalence des troubles spécifiques des apprentissages dans une cohort d'enfants en difficultiés scolaries.

BACKGROUND: Specific learning disorders (SLD) are poorly known and studied in Tunisia. A National research project on their prevalence was launched recently. Aim of this study was to estimate prevalence of SLD in a cohort of children with school failure. METHODS: Cross-sectional descriptive study with a population of 287 First and Third grade Primary School students, screened by their teachers as facing learning problems through a systematic screening process based on achievement and behavior. Multidisciplinary assessment consisted in general medical examination, child psychiatry, child neurology, speech therapy and psychology (cognitive). 180 students have been assessed. RESULTS: Prevalence of SLD over study population was 32%, which gives a general population prevalence 6.4%. Most common SLDs were dyslexia and dyscalculia. Most of children with SLD came from disadvantaged social groups. CONCLUSION: Despite methodological limitations, this first study on SLD sheds some light on their prevalence in Tunisian students, and opens perspectives for future more focused studies and interventions for their management in Tunisia.

Prevalence and score of minor physical anomalies in patients with schizophrenia and their first degree relatives: a Tunisian study.

UNLABELLED: Minor physical anomalies (MPAs) have been consistently reported to be more frequent in schizophrenia subjects. Limited research has been conducted on these anomalies among biological relatives of patients with schizophrenia. The aims of this study were to investigate the MPAs in a Tunisian population: subjects with schizophrenia, their healthy siblings and control subjects. This study hypothesized that the mean MPAs score would be greater in patients than controls and that siblings would have intermediate scores. Furthermore, it was hypothesized that MPAs scores would be associated with negative and disorganised symptoms of schizophrenia. METHODS: We assessed 93 subjects with schizophrenia, 59 of their healthy siblings and 71 healthy controls, matched on gender and age. MPAs were assessed through use of a standardized scale derived from the Waldrop Scale [D. Gourion, G. Viot, C. Goldberger, M. Cartier, M.C. Bourdel, M.F. Poirier, J.P. Olié, H. Lôo, M.O. Krebs, 2001. French validation of a Minor Morphologic Anomalies Scale in schizophrenic patients and their parents. Encephale 27, 143-147]. The schizophrenia psychopathology was evaluated by the Positive and Negative Syndrome Scale (PANSS), Global Assessment of Functioning (GAF) and the Clinical Global Impression-Severity (CGI-S). RESULTS: Subjects with schizophrenia showed significantly higher MPAs score than siblings (4.6 ± 2.8 vs. 3.0 ± 2.1, p<0.0001) and controls groups: 1.9 ± 1.5 (p<0.0001). Siblings had significantly higher score than control subjects (p=0.02). MPAs were correlated negatively with age of onset of the disease, and age of first hospitalisation, and positively with number of hospitalisations. Positive correlations were found between MPAs and PANSS total score, PANSS negative sub-score and CGI-S score. COMMENTS: Results of this study showed that MPAs are more frequent in subjects with schizophrenia and their siblings compared to control subjects. Positive correlations were found between MPAs, age of onset, severity of illness, and negative symptoms of schizophrenia, suggesting that those anomalies are correlated to severe form of schizophrenia.

A gender-specific association of interleukin 1 receptor antagonist polymorphism with schizophrenia susceptibility.

OBJECTIVE: Recent genetic studies have revealed that the interleukin (IL) 1 gene complex is associated with schizophrenia in the Caucasian population; however, data from the North African population are limited. To further assess the role of interleukin 1 receptor antagonist protein (IL1Ra) in schizophrenia, we examined a functional multiallelic polymorphism localised in intron 2 of this receptor gene associated with an altered level of IL1Ra. METHODS: In the present case-control study, we have analysed the (86 bp) n polymorphism of the interleukin 1 receptor antagonist (IL1RN) gene (RS 1794068) by polymerase chain reaction genotyping in 259 patients with schizophrenia and 178 healthy controls from the Tunisian population. RESULTS: We showed that the frequencies of the IL1RN*2/2 genotype and allele 2 were higher in the patient group compared with the control group, and the difference was statistically significant [13.5% vs. 5.6%, p = 10-3, odds ratio (OR) = 3.2% and 32.8% vs. 21.9%, p = 3 × 10-4, OR = 1.76, respectively). When we evaluated the association between this genetic polymorphism and the clinical variables of schizophrenia, we found that the frequencies of the 2/2 genotype and allele 2 were significantly higher in the male patient group (p = 10-4 and 10-5, respectively) compared with the male control group, indicating a substantially increased risk for sex-onset schizophrenia with inheritance of the IL1RN2 allele. When the association between the genotypes and outcome was evaluated by multiple logistic regression analysis, the adjusted OR for the IL1RN genotypes remained statistically significant [1.39; 95% confidence interval (CI) = 1.11-1.73; p = 0.003]. CONCLUSION: The intron 2 polymorphism in IL1RN or a genetic polymorphism at proximity seems to be associated specifically with schizophrenia in the Tunisian male population.

Case control study: G-allele of rs4244165 in JAK1 gene correlated with high-level brief psychiatric rating scale in bipolar patients.

Bipolar disorder (BD) is a chronic and clinically complex disease, characterized by pathological disturbances in mood and energy. Cytokines can access the brain and their signaling pathways affect brain functions, such as neurotransmitter metabolism, neuroendocrine function, neural/synaptic plasticity, and mood neural circuitry. JAK 1 is the most common phosphorylation protein combined with the tyrosine kinase cytokine receptors; therefore, we investigated the association between the Janus family kinase 1 (JAK1) gene polymorphisms (rs2780895, rs4244165, and rs17127024) and susceptibility to BD. The case study population included 93 patients diagnosed with BD and 112 healthy controls, selected from the central coastal region of Tunisia. Polymerase chain reaction-restriction fragment length polymorphism was used to investigate these 3 JAK1 polymorphisms. We compared the sociodemographic and clinical parameters of 3 genotypes of this single nucleotide polymorphisms rs2780895, rs4244165, and rs17127024 of the JAK1 gene. The frequencies of the 3 genotypes were similar in the patient and control groups. One-way analysis of variance revealed a significant variation in rs4244165. After hospitalization, the average of the brief psychiatric rating scale score was significantly higher for the wild-type GG genotype than that for the double-mutation TT genotype (31.23% vs 22.85%, P = .043). The least significant difference post hoc test also showed a significant difference between the GG and TT genotypes at both hospital admission (P = .001) and after hospitalization (P = .012), with the GG genotype being associated with a higher brief psychiatric rating scale score. Haplotypic analysis revealed that the wild-type haplotype with the highest frequency (46.62%) was CTG. Our results showed no association between the 3 studied positions and bipolar disorder. However, the G-allele of rs4244165 in JAK1 is associated with the highest level of the brief psychiatric rating scale in patients with bipolar disorder. The JAK/signal transducer and activator of transcription pathway is an interesting therapeutic route that requires further investigations. Studying their regulatory regions can provide a clearer picture of all the interactions involved in the regulation of genetic expression in response to treatment.

Depression among medical students in Tunisia: Prevalence and associated factors.

BACKGROUND: Medical school is known for its lengthy process, which is both physically and emotionally draining. Students' mental balance would shrink as they progress in their medical training. A systematic review and meta-analysis reported that the prevalence of depressive symptoms among medical students remained relatively constant at 27.2%. AIM: To assess the prevalence of depressive symptoms among Tunisian medical students and evaluate its associated factors. METHODS: This is a descriptive cross-sectional study that was carried out in the second semester of the academic year 2017/2018, between April 2018 and July 2018 among 1138 medical students. Data were collected using a socio-demographic questionnaire and the Beck Depression Inventory-II (BDI-II). RESULTS: Sixty-four percent (n = 728) of the participants had depressive symptoms, of which 266 (23.4%) met the criteria for mild, 271 (23.8%) for moderate, and 191 (16.8%) for severe depressive symptoms. Female gender, low socio-economic level, smoking habits and history of mental disorder, performing leisure and physical activities, satisfaction toward a career choice, and happiness perception were the main prognostic factors for depression among medical students. Although academic grades may not be considered a prognostic factor, final-year students appeared to be less depressive than their colleagues. CONCLUSION: These findings give insight into mental health issues and comorbidities among Tunisian medical students. It is a hopeful request for decision-makers and academic authorities to set serious measures and draw effective interventions to minimize the currency of psychological distress among this subpopulation.

In vitro effects of three antidepressant drugs on plasma paraoxonase activity.

BACKGROUND: Paraoxonase 1 (PON1) is important in organophosphates and xenobiotic metabolism and as an antioxidant bio-scavenger. PON1 activity was shown to significantly decrease in depressed patients after antidepressant treatment instauration. Our aim was to investigate the in vitro inhibitory effects of three antidepressants (imipramine, amitriptyline and fluoxetine) on PON1 activity. METHODS: Plasma from healthy volunteers was spiked with antidepressant drugs. The working solutions were then diluted with plasma to obtain concentrations that covered the therapeutic margin. PON1 was tested by a kinetic method in triplicate after incubation at 37°C for 2 h. RESULTS: Tricyclic antidepressants significantly inhibited PON1. Fluoxetine had no effect. The inhibition percentage for imipramine was 15.6% at 100 µg/L after incubation for 1 h (131±1 vs. 155±2 IU/L; p<0.01). At 350 µg/L, the inhibition percentage for imipramine 19.2% after 1 h and 20.2% after 2 h. Amitriptyline was a stronger inhibitor: 26% after 30 min at 125 µg/L. At 250 µg/L, the inhibition percentage for amitriptyline was 36.5% after 30 min (100±4 vs. 159±2 IU/L; p<0.01). CONCLUSIONS: The tested tricyclic antidepressants significantly inhibit PON1 activity in a concentration-dependent manner. Amitriptyline had a higher inhibition potency than imipramine.

[Pseudocholinesterase activity in type 1 bipolar patients]. / Étude de l'activité pseudocholinestérasique chez des patients bipolaires de type 1.

This study aims to investigate the variation of pseudocholinesterase activity (BuChE) in bipolar patients and to explore its relation to the clinical and therapeutic characteristics of this disease. Our study included 105 patients with bipolar disorder and 100 control subjects aged 38.7 ±â€Š12.2 and 36.4 ±â€Š15.7 y, respectively. BuChE was determined by kinetic methods on Cobas Integra 400 plus™. Compared with controls, patients had a significantly higher pseudocholinesterase activity. Moreover, this increase was significantly associated (p = 0.001) with bipolar disorder with sensibility of 58% and specificity of 62% at threshold of 7392 IU/L. There was no significant change in pseudocholinesterase activity in relation to illness episodes and treatment, whereas the lowest values of this activity were seen in euthymic patients and those taking psychotics. Therefore, this activity is a real interest in the biological monitoring of patients as a risk factor for neurodegenerative diseases associated with bipolar disorder. But it would be most useful to evaluate their interest as a predictor of bipolar disorder in patients at risk.