Impact of interleukin 13 (IL13) genetic polymorphism Arg130Gln on total serum immunoglobulin (IgE) levels and interferon (IFN)-γ gene expression

This cross-sectional study was designed to investigate the extent of genetic susceptibility by targeting variants in interleukin (IL)-4/IL-13 signalling pathways leading to atopic disease in early childhood. We evaluated involvement of five single nucleotide polymorphisms IL4 C-590T, IL13 C-1055T, IL13 Arg130Gln, IL4RA Ile50Val and IL4RA Gln576Arg, in the control of serum total and antigen-specific immunoglobulin (Ig)E levels. Furthermore, we analysed their association with changes in gene expression of five cytokines having key roles in inflammatory and anti-inflammatory immune response [IL-4, IL-13, interferon (IFN)-γ, IL-8 and IL-10]. Total and antigen-specific IgE levels in serum and gene expression of selected cytokines in peripheral blood were measured in 386 children aged 1-8 years. TaqMan allelic discrimination, amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and restriction fragment length polymorphisms (RFLP) methods validated by sequencing were used for genotyping. All genotypes for children with total and antigen-specific IgE levels in the normal range were in Hardy-Weinberg equilibrium. Gene expression analyses were carried out using TaqMan gene expression assays. We found elevated total IgE levels in carriers of IL13 Arg130Gln variant allele [odds ratio (OR) = 1·84; 95% confidence interval (CI) = 1·16-2·93]. This effect was more apparent for boys (OR = 2·31; 95% CI = 1·25-4·28). However, no significant association was observed for the other four variants examined. We found up-regulation of IFN-γ in children with elevated serum total IgE levels carrying the Arg130 allele (P = 0·005). No differences were found for IL4, IL8 or IL10, while IL13 gene expression was under the detection limit. IL13 Arg130Gln genotypes can play a role in genetic susceptibility to allergy via regulation of serum total IgE levels and affecting IFN-γ gene expression.

Plasma concentrations of selected antioxidants in autistic children and adolescents

Few studies have demonstrated an increased vulnerability to oxidative stress in autism. The results of previous studies have shown that endogenous antioxidant defence is insufficient, indicating that exogenous antioxidant could play a crucial role for oxidative stress prevention in autism. Plasma concentrations of vitamins C, E, A, carotenoids beta-carotene and lycopene were measured in 51 subjects with autistic spectrum disorders aged 5-18 years (27 children aged 5-10 years, 24 subjects aged 11-18 years). Older autistic group was compared with a group of healthy Slovak subjects aged 11-18 years. Older autistic subjects vs. healthy control showed significantly higher vitamin C and beta-carotene plasma values with 92% and 71% vs 54% and 13% of optimal over-threshold values, respectively. This indicates a reduced risk of free radical disease. In younger vs. older autistic group the similarly high plasma vitamin concentrations were recorded. Favourable values of these vitamins suggested that consumption of fruit and vegetables in autistic subjects is optimal. Autistic average vitamin E and A plasma concentrations (non-significantly changed in comparison to control group) were below-threshold with low percentage of over-threshold values. Insufficient vitamin E and A plasma values indicate lower consumption of food rich in vitamins A and E (e.g. whole-grain products, plant oils, oil seeds, nuts, fat spreads and dairy products). Autistic average lycopene concentration is lower in comparison to published non-Slovak data. Conclusions of this pilot study suggest that plasma concentrations of exogenous antioxidants, vitamins E and A, and lycopene in autistic subjects are insufficient (Tab. 1, Ref. 30). Full Text (Free, PDF) www.bmj.sk.

The redox state of glutathione in erythrocytes of individuals with Down syndrome

BACKGROUND

The redox state of glutathione has been used as indicator for the redox environment of the cell.

OBJECTIVES

To investigate relationships between the redox environments, the SOD activity, total antioxidant status and the oxidation stress markers production (MDA and lipofuscin).

METHODS

Individuals with Down syndrome and age-matched healthy controls were enrolled into a study. Some parameters of oxidative stress in serum were determined: reduced glutathione, oxidized glutathione, redox potential of this couple (Eh), activity of superoxide dismutase in the red blood cells as well as malondialdehyde and lipofuscin.

RESULTS

In the group of persons with DS statistically significant decrease in the GSH concentration was found, however, no differences in the GSSG concentration versus controls was observed. The redox potential values for couple GSH/GSSG are a statistically significantly increased in DS individuals compared to controls.

CONCLUSION

In this study we highlighted the different ways of view at the role of GSH in metabolism of persons with DS. It is useful to look at the GSH and GSSG concentrations separately as well as at redox potential value, which influence total redox state of organism (Tab. 2, Fig. 3, Ref. 30) Full Text (Free, PDF) www.bmj.sk.

Effects of a single transdermal nicotine dose on cognitive performance in adults with Down syndrome

Subjects with Down syndrome exhibit various types of cognitive impairment. Neuropathological and neurochemical studies revealed similarities between Down syndrome and Alzheimer's disease, cholinergic deficits being the most consistent findings. To explore the potential for cognitive enhancement utilizing nicotinic stimulation, 8 patients with Down syndrome (aged 18.5-31 years) received placebo and a single dose of transdermal nicotine (5 mg patch) over 2h in a single-blind, within-subjects repeated measures design. Auditory event-related potentials (ERPs) and neuropsychological tests, comprising digit symbol performance subtest from WAIS-R and the Frankfurt Attention Inventory (FAIR) were performed. Effects of nicotine administration in Down syndrome individuals were a decrease of ERP-P3 latency in 7 of 8 subjects (electrode position Cz: 386.9+/-24.0 ms vs. 363.1+/-26.9.2 ms, placebo vs. nicotine, respectively; P = 0.058) and an increase of ERP-P3 amplitude in 6 of 8 subjects (electrode position Cz: 17.4+/-5.5 vs. 18.0+/-4.5 microV, placebo vs. nicotine respectively; P = 0.725). Neuropsychological tests exhibited improvements in digit symbol performance subtest in 4 of 8 subjects and 7 of 8 subjects in the Frankfurt Attention Inventory. These results suggest that stimulating central nicotinic receptors might have an acute cognitive benefit in young adult Down syndrome subjects.