Haplotypes of TNFα/ß Genes Associated with Sex-Specific Paranoid Schizophrenic Risk in Tunisian Population.

Several medical research findings have announced a strong association between the biology of cytokines and various brain activities. Since growing evidences suggest the crucial and complex role of the tumor necrosis factor in the CNS, we have hypothesized that functional genetic variants of the LTA and TNFA genes (LTA +252A/G (rs909253) and TNFA -857C/T (rs1799724) and TNFA -238G/A (rs361525)) may be involved in the predisposition to schizophrenia. This research is based on a case-control study. The RFLP-PCR genotyping was conducted on a Tunisian population composed of 208 patients and 208 controls. We found a strong significant overrepresentation of the minor alleles (G, T, and A, respectively) in all patients compared with controls (p = 0.003, OR = 1.55; p = 0.005, OR = 1.78; and p = 0.0001, OR = 1.74, respectively). This correlation was confirmed for male but not for female patients. Interestingly, the frequencies of the minor alleles were significantly more common among patients with paranoid schizophrenia when compared with controls (p = 0.003, OR = 1.75; p = 5 · 10-6, OR = 3.04; and p = 4 · 10-6, OR = 2.35, respectively). This potential association was confirmed by a logistic binary regression analysis only for the development of the paranoid form of schizophrenia (p = 0.001/OR = 2.6; p = 0.0002/OR = 3.2; and p = 0.0004/OR = 3.1, respectively) and remained not significant for the other subtypes. Moreover, our study showed an important association between GCA haplotype and the development of this pathological form (p = 10-4, OR = 3.71). In conclusion, our results proved a significant association between the three polymorphisms and paranoid schizophrenia, at least in the Tunisian population, suggesting a substantially increased risk for paranoid schizophrenia with dominant inheritance of these three minor alleles.

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.

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.

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.

Toxoplasma gondii infection in schizophrenia and associated clinical features.

The belief that latent toxoplasmosis is asymptomatic has been questioned, in particular due to the repeated highlighted link between the Toxoplasma gondii infection and an increased incidence of schizophrenia. However, to understand this relationship, the effect of infection with Toxoplasma gondii on the severity of schizophrenia has been poorly studied. Our work focused on comparing the prevalence of Toxoplasma infection between schizophrenic patients and healthy controls, as well as comparing the clinical features and the demographic characteristics between Toxoplasma-seronegative and Toxoplasma-seropositive patients with schizophrenia. The rate of IgG antibody in the schizophrenia patients was 74.8% compared 53.8% in controls. Patients with schizophrenia had a significantly higher mean of serum IgG antibodies to T. gondii compared to controls. The seropositive male patients had a higher age of disease onset, a higher BPRS score, a greater negative PANSS score and a lower GAF score than the seronegative male patients. These results suggest a higher severity of clinical symptoms in the male patients with schizophrenia. This study provides further evidence to the hypothesis that exposure to Toxoplasma may be a risk factor for schizophrenia. Moreover, toxoplasmosis in men with schizophrenia may lead to more severe negative and cognitive symptoms and a less favorable course of schizophrenia.

Paraoxonase 1 activity and lipid profile in schizophrenic patients.

OBJECTIVE: This study aimed to investigate the variations of paraoxonase 1 (PON1) activity and lipid profile in patients with schizophrenia and the association of this activity with the sociodemographic, clinical and therapeutical characteristics of this population. PATIENTS AND METHODS: Our cross-sectional study included 140 schizophrenic patients and 119 control subjects aged respectively 37.3±10.4 and 41.4±10 years. PON1 activity was determined using Konelab 30™ equipment (Thermo Electron Corporation). Plasma total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (c-HDL) and low-density lipoprotein cholesterol (c-LDL) concentrations were determined using Cobas 6000™ (Roche Diagnostics), apolipoproteins (ApoA1, ApoB) and lipoprotein (a) (Lp(a)) were determined using Integra 400 plus (Roche Diagnostics). RESULTS: Compared to controls, patients had no significant decrease of PON1 activity and significantly lower ApoA1, c-HDL levels, and significantly higher levels of TG, ApoB, Lp(a) and TC/c-HDL and ApoB/ApoA1 ratios. Furthermore, PON1 activity was correlated with TG/c-HDL ratio. The lowest PON1 activity was noted in obese patients, in paranoid sub-type and in patients treated with combination of typical and atypical antipsychotics without significant difference. Moreover, it was associated with gender and cigarette smoking but not with alcohol consumption status. CONCLUSION: Schizophrenic patients had a decrease in PON1 activity and perturbations in their lipid profiles that contribute to increase the risk of cardiovascular diseases. In addition, our results revealed that there was no association between the decrease of PON1 activity and any demographic or clinical characteristics. Therefore, such patients require specific care, particularly with regard to their lipid profile.

Prevalence and Impact of Anxiety and Depression on Type 2 Diabetes in Tunisian Patients over Sixty Years Old.

Objectives. To estimate the prevalence of anxiety and depression using the Hospital Anxiety and Depression Scale (HADS) in a population aged over sixty years with type 2 diabetes and to study the impact of anxiety and depression on glycemic balance and disease outcome. Results. The prevalence of anxiety and depression in the 62 subjects included in the study was, respectively, 40.3% and 22.6%. We found a relationship between these disorders and complicated diabetes. The subjects having an imperfectly balanced diabetes had a higher average anxiety score than those having a good glycemic control (9.1 ± 4.2 versus 6.5 ± 3.1; P = 0.017). No relationship was found between diabetes balance and depression. Conclusion. Association between anxiety and depressive disorders and diabetes is frequent and worsens patients' outcome, in terms of diabetes imbalance as well as in terms of diabetic complications. Our study shows that there is need for physicians to detect, confirm, and treat anxiety and depressive disorders in elderly diabetic patients.

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.

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.

[Butyrylcholinesterase activity in schizophrenic patients]. / Étude de l'activité butyrylcholinestérase chez des patients schizophrènes.

Butyrylcholinesterase (BChE) is an enzyme that has been investigated for its putative role in neurodegenerative and neuropsychiatric disorders. The aim of our work was to study BChE activity variations in schizophrenic patients and to investigate the involvement of this enzyme in schizophrenia and the importance of determining its activity in this disease. This cross-sectional study was carried out 131 (104 males and 27 females, mean age  = 38.0  ±â€Š 11.4 years) patients with chronic schizophrenia according DSM-IV criteria and 90 (64 males and 26 females, mean age  = 37.1  ±  15.9 years) healthy controls. Plasma BChE activity was determined by a kinetic method on Integra 400plus(TM) (Roche Diagnostics). Patients with schizophrenia had higher plasma BChE activity than controls (P < 0.0001). Female patients had higher BChE activity and smokers had lower BChE activity than non-smokers either in patients and controls. In patients with schizophrenia, BChE activity was not differed with age, alcohol status and clinical sub-types, and was not correlated to duration of illness. Concerning therapeutic features, BChE activity was higher in patients treated with antipsychotics monotherapy than those treated with an association of antipsychotic and anticholinergic drugs, without significant difference (P  = 0.196). Schizophrenic patients showed an increase BChE activity, which could be related to the pathophysiology of schizophrenia.

[Compared effects of etomidate and propofol for anaesthesia during electroconvulsive therapy]. / Effets comparés de l'étomidate et du propofol pour l'anesthésie lors de l'électroconvulsivothérapie.

OBJECTIVE: Electroconvulsive therapy (ECT) requires repeated short-term anaesthesia with muscle relaxation and deep narcosis and uses several anaesthetic agents. The aim of this study was to assess the quality of the anaesthetic technique applied for ECT by comparing two products: propofol and etomidate. METHODS: This was a prospective randomised study that included ECT sessions. Patients were distributed into two groups. Patients of Group 1 underwent general anaesthesia with propofol (1.5mg.kg(-1)) and succinylcholine (0.75 mg.kg(-1)). Patients of Group 2 were administered etomidate (0.15 mg.kg(-1)) and succinylcholine (0.75 mg.kg(-1)). None of the patients included had any absolute or relative contraindication to ECT. RESULTS: 104 sessions were included, with 52 sessions per group. Group 1 was composed of 12 patients and Group 2 of 13. The demographical characteristics and indication for ECT were comparable in the two groups. There was no haemodynamic variation (notably drop in blood pressure) between the groups. The duration of seizures was significantly more prolonged in the etomidate group (28.76 +/- 3.29 seconds) than in the propofol group (23.84 +/- 7.18 seconds), with significant difference (p = 0.000018). Awakening was calm in both groups. CONCLUSION: The pharmacological properties of propofol and etomidate reply precisely to the requirements of anaesthesia for ECT. Nevertheless, no drop in blood pressure was observed with the greater prolongation of seizures in the etomidate group compared with the propofol group.