Association of glutathione S-transferases M1, T1 and P1 gene polymorphisms with attention deficit and hyperactivity disorder in Korean children

Arsenic and fluoride co-exposure through drinking water and their impacts on intelligence and oxidative stress among rural school-aged children of Lahore and Kasur districts, Pakistan

Arsenic (As), and fluoride (F^-) are potent contaminants with established carcinogenic and non-carcinogenic impacts on the exposed populations globally. Despite elevated groundwater As and F^- levels being reported from various regions of Pakistan no biomonitoring study has been reported yet to address the co-exposure impact of As and F^- among school children. We aimed to investigate the effects of these two contaminants on dental fluorosis and intelligence quotient (IQ) along with the induction of oxidative stress in rural children under co-exposed conditions. A total of 148 children (5 to 16 years old) from the exposed and control group were recruited in the current study from endemic rural areas of Lahore and Kasur districts, Pakistan having elevated As and F^- levels in drinking water than permissible limits. We monitored malondialdehyde and its probable association with antioxidants activity (SOD, CAT, and GR) as a biomarker of oxidative stress. GSTM1/T1 polymorphisms were measured to find the impact of As on health parameters. Mean urinary concentrations of As (2.70 vs. 0.016 µg/L, P < 0.000) and F^- (3.27 vs. 0.24 mg/L, P < 0.000) as well as the frequency of dental fluorosis were found elevated among the exposed group. The cases of children with lower IQ were observed high in the exposed group. Additionally, lower concentrations of antioxidants (SOD, CAT, and GR) were found suggesting high susceptibility to F^- toxicity. The findings suggest that F^- accounted for high variations in health parameters of children under the co-exposure conditions with As.

Interaction of Blood Manganese Concentrations with GSTT1 in Relation to Autism Spectrum Disorder in Jamaican Children

Using data from 266 age- and sex-matched pairs of Jamaican children with autism spectrum disorder (ASD) and typically developing (TD) controls (2-8 years), we investigated whether glutathione S-transferase theta 1 (GSTT1) modifies the association between blood manganese concentrations (BMC) and ASD. After adjusting conditional logistic regression models for socioeconomic status and the interaction between GSTT1 and GSTP1 (glutathione S-transferase pi 1), using a recessive genetic model for GSTT1 and either a co-dominant or dominant model for GSTP1, the interaction between GSTT1 and BMC was significant (P = 0.02, P = 0.01, respectively). Compared to controls, ASD cases with GSTT1-DD genotype had 4.33 and 4.34 times higher odds of BMC > 12 vs. ≤ 8.3 μg/L, respectively. Replication in other populations is warranted.

WITHDRAWN: Co-exposure effects of arsenic and fluoride on intelligence and oxidative stress in school-aged children: A cohort study

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The Nrf2 pathway in psychiatric disorders: pathophysiological role and potential targeting

Introduction: All psychiatric disorders exhibit excitotoxicity, mitochondrial dysfunction, inflammation, oxidative stress, and neural damage as their common characteristic. The endogenous nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway is implicated in the defense mechanism against oxidative stress and has a significant role in psychiatric disorders.Areas covered: We explore the role of Nrf2 pathway and its modulators in psychiatric disorders. The literature was searched utilizing various databases such as Embase, Medline, Web of Science, Pub-Med, and Google Scholar from 2010 to 2020. The search included research articles, clinical reports, systematic reviews, and meta-analyses.Expert opinion: Environmental factors and genetic predisposition can be a trigger for the development of psychiatric disorders. Nrf2 downregulates certain inflammatory pathways and upregulates various antioxidant enzymes to maintain a balance. However, its intricate balance with NF-Kβ (Nuclear factor kappa light chain enhancer of activated B cells) and its crosstalk with the transcription factor Nrf2 is critical in severe oxidative stress. Several Nrf2 modulators are now in clinical trials and can help reduce oxidative stress and neuroinflammation. There are immense potential opportunities for these modulators to become a novel therapeutic option.

Glutathione S-transferase gene polymorphisms (GSTT1 and GSTM1) and risk of schizophrenia: A case-control study in Chinese Han population

Schizophrenia (SCZ) is a chronic disability disorder related to oxidative stress. Glutathione S-transferase (GST) is a group enzyme that protects cells and tissues from oxidative stress damage. Among GSTs, GSTT1 and GSTM1 have well defined genetic polymorphisms. The purpose of our research was to explore the correlation between GSTT1 and GSTM1 polymorphism and SCZ risk in Chinese Han population.A total of 650 subjects (386 SCZ patients and 264 healthy individuals) were included in this case-control designed study. The GSTT1 and GSTM1 polymorphisms were analyzed by multiplex polymerase chain reaction (PCR). We explored the relationship between these 2 polymorphisms and the risk of SCZ.We found that the GSTT1 null genotype had a protective effect on the development of SCZ [odds ratio (OR) = 0.601, 95% confidence interval (95% CI) = 0.412-0.986, P = .031]. We also found that the combination of null genotypes of the GSTT1 and GSTM1 genes was made at a lower risk of SCZ (OR = 0.452, 95% CI = 0.238-0.845, P = .028). However, we found no correction between Positive and Negative Syndrome Scale score (PANSS) and GSTM1, GSST1 genotypes in SCZ patients.Our finding revealed that GSTT1 null polymorphisms may be related to the reduced risk of SCZ in Chinese Han population, and this risk was further reduced with the combination of GSTT1 null polymorphisms and GSTM1 null polymorphisms.

Evaluation of the efficacy of drug treatment based on measurement of the oxidative stress, using reactive oxygen metabolites and biological antioxidant potential, in children with autism spectrum disorder and attention deficit hyperactivity disorder

Background

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, mainly characterized by impairment of social communication and restricted interests. ASD is frequently accompanied by attention deficit hyperactivity disorder (ADHD), which is characterized by carelessness, hyperactivity and impulsivity (ASD/ADHD). It has been suggested that ASD and ADHD are associated with oxidative stress, that is, that patients with ASD/ADHD are in a state of increased oxidative stress. There are currenr tly no objective or biological test criteria for evaluating the efficacy of drug therapy in these patients. The purpose of this study was to evaluate whether oxidative stress markers [serum reactive oxygen metabolites (d-ROMs) levels and biological antioxidant potential (BAP)] can be used as objective indicators for evaluating the efficacy of drug treatment in ASD/ADHD patients.

Methods

The subjects of this study subjects were 50 Japanese patients with ASD/ADHD aged 4 to 14 years old. Serum samples were obtained from the patients to measure the serum levels of d-ROMs and the serum BAP. The study subjects were divided into two age groups: preschool children (4 to 6 years old) and school-age children (7 to 14 years old), and the serum levels of d-ROMs, serum BAP, serum BAP/d-ROMs ratio (hereinafter, the prefix serum will be dropped), and scores on the Parent-interview ASD Rating Scales-Text Revision (PARS-TR) and ADHD Rating Scale (ADHD-RS) were determined before and after drug therapy and compared between the two groups. In addition, changes in the d-ROMs, BAP and BAP/d-ROMs ratio and changes in the scores on the PARS-TR and ADHD-RS after treatment were also analyzed.

Results

Significant decrease of the d-ROMs, BAP, and scores on the PARS-TR and ADHD-RS, with a significant increase of the BAP/d-ROMs ratio, was observed after treatment. In addition, a significant correlation was observed between the changes in the d-ROMs and changes in the scores on the PARS-TR and ADHD-RS after treatment in the school-age ASD/ADHD children.

Conclusion

Our results suggest the possibility that the serum level of d-ROMs may be useful as an objective assessment marker to supplement the subjective assessment of the effects of drug treatment in school-age children with ASD/ADHD.

Relationship between Antioxidant Status and Attention Deficit Hyperactivity Disorder Among Children

Background:

Attention deficit hyperactivity disorder (ADHD) is one of the prevalent neuropsychiatric disorders in childhood. In general, diagnoses of ADHD include inattention, hyperactivity, and impulsivity. Recent studies have reported increased oxidative stress in psychiatric disorders such as ADHD, but the results are conflicting. This research aimed to study the relationship between antioxidant status and ADHD in children of 6–13 years old.

Methods:

From schools, 32 ADHD students whose diseases were diagnosed by child and adolescence psychiatrist based on Diagnostic and Statistical Manual of Mental Disorders-IV index were recruited; moreover, 32 healthy subjects, which according to the medical history questionnaire of psychiatric disorder had not had chronic disease, were selected. Total antioxidant capacity (TAC), catalase (CAT), glutathione (GSH), and malondiadehyde (MDA) were measured. General information, health history, and medication history were collected. All participants completed a 168-item food frequency questionnaire. Dietary intakes of antioxidants were obtained through this questionnaire.

Results:

There was no significant difference between mean of energy intake and Zn, Se, vitamin E, C, and β-carotene as antioxidants between the two groups. The mean of serum TAC, GSH level, and CAT level in the patients were significantly lower than the healthy group (P < 0.001), but the mean of MDA was not significantly different between the two groups (P = 0.18).

Conclusions:

The result of this study indicates that, in ADHD, the serum levels of GSH, CAT, and TAC decrease; the level of antioxidant in the serum has been compromised to fight oxidative stress. More perspective studies with large sample sizes are essential to confirm these findings.