Genetic polymorphisms modifying oxidative stress are associated with disease activity in rheumatoid arthritis patients

Tumour necrosis factor gene polymorphisms in Egyptian patients with rheumatoid arthritis and their relation to disease activity and severity

Aim of the study

The present case control study was conducted to assess the association of LTA 252 A>G, TNF-α 308 G>A, and TNF-α 1031 T>C gene polymorphisms with rheumatoid arthritis (RA), and their involvement in disease activity and severity.

Material and methods

A total of 70 Egyptians, including 35 RA patients and 35 healthy control individuals, were included in the study. The RA patients comprised 34 females and one male. Cases with RA were diagnosed by a rheumatologist and fulfilled the 2010 ACR/EULAR criteria. Modified disease activity score (DAS28) was used to assess disease activity. Van Der Heijde-modified Sharp score (vdHSS) was used to assess radiological changes for assessment of disease severity. PCR-RFLP was used to detect the association of LTA 252 A>G, TNF-α 308 G>A, and TNF-α 1031 T>C gene polymorphisms with RA.

Results

TNF-α 308 G allele and TNF-α 308 GG genotype were significantly higher in RA patients compared to healthy control subjects (p = 0.04 and p = 0.001, respectively). TNF-α 308 G allele and GG genotype were significantly higher in the RA non-remission group compared to the remission group (p = 0.008, p < 0.001). Patients with the TNF-α 308 AG genotype had higher mean of Sharp score compared to the patients with the GG and AA genotypes (p = 0.007). There was no significant association between LTA 252 A>G and TNF-α 1031 T>C gene polymorphisms and RA.

Conclusions

Our results suggest that TNF-α 308 G/A gene polymorphism is genetically associated with RA and involved in disease activity and severity in Egyptian patients.

Association between SOD1, CAT, GSHPX1 polymorphisms and the risk of inflammatory bowel disease in the Polish population

PURPOSE

The main aim of this study was investigate the association between the genetic polymorphism of antioxidant enzyme genes: SOD1, CAT and GSHPX1 and the risk of inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis in the Polish population.

METHODS

A total of 445 subjects including 200 patients with IBD and 245 controls were allowed in this study. We determined activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx1) and examination their association with the SNPs of respective genes (SOD1 +35A/C, CAT C-262T and GSHPX1 Pro197Leu). RFLP technique was used to determine the selected genes polymorphisms. Antioxidant enzymes activity were evaluated in erythrocyte hemolysate of 23 patients with non-active IBD and 30 healthy participants.

RESULTS

The A/C genotype and the C allele frequencies of A/C polymorphism of SOD1 gene were significantly associated with the reduced risk of IBD (OR=0.43; 95% CI 0.23; 0.83). Alike, C/T (OR=0.45; 95% CI= 0.29; 0.70) and T/T genotype (OR=0.43; 95% CI= 0.21; 0.87) of GSHPX1 gene polymorphism diminished the susceptibility to IBD. A significant decrease of CAT (P=0.028) and increase of GPx1 (P=0.025) enzyme activities were seen in IBD patients compared to control.

CONCLUSIONS

Our data confirm dysregulated antioxidant capacity in patients suffering from IBD. Both, the SOD1 A/C genotype as well as GSHPX1 C/T and T/T genotypes may be associated with a reduction risk of IBD in the Polish population.

Is 4-Hydroxynonenal a Predictive Parameter for the Development of Joint Erosion in Patients With Rheumatoid Arthritis?

Objectives

This study aims to evaluate serum 4-hydroxynonenal (4-HNE) levels and its clinical and radiological significance in patients with rheumatoid arthritis (RA).

Patients and methods

The study included 40 patients (8 males, 32 females; mean age 51.4±11.2 years; range 24 to 72 years) with RA and 30 healthy controls (8 males, 32 females; mean age 53.0±11.7 years; range 24 to 72 years. Serum 4-HNE levels were measured using sandwich enzyme-linked immunosorbent assay method. Patients with disease activity score 28 ≤3.2 and >3.2 were allocated into low and high/moderate disease activity groups, respectively. Additionally, patients were divided into two groups as early RA (disease duration ≤2 years) and established RA (disease duration ≥2 years). Functional disability was evaluated using health assessment questionnaire. Radiographs were scored using the modified Larsen scoring.

Results

Serum 4-HNE levels in patients with RA were significantly higher than controls (p=0.001). Serum 4-HNE levels did not correlate with laboratory or clinical parameters of disease activity including erythrocyte sedimentation rate, C-reactive protein, disease activity score 28, and health assessment questionnaire. Serum 4-HNE levels were higher in patients with established RA than patients with early RA (r=0.487, p=0.001). Besides, modified Larsen score which indicates structural damage correlated significantly with serum 4-HNE levels (p=0.001).

Conclusion

These results indicate that serum 4-HNE levels may be used as an indicator for structural damage such as erosions in the early stage of RA; however, they are not efficient to monitor disease activity.

Genetic disorders coupled to ROS deficiency. Redox Biol. 2015;6:135-156. [PMID: 26210446 DOI: 10.1016/j.redox.2015.07.009]

Maintaining the redox balance between generation and elimination of reactive oxygen species (ROS) is critical for health. Disturbances such as continuously elevated ROS levels will result in oxidative stress and development of disease, but likewise, insufficient ROS production will be detrimental to health. Reduced or even complete loss of ROS generation originates mainly from inactivating variants in genes encoding for NADPH oxidase complexes. In particular, deficiency in phagocyte Nox2 oxidase function due to genetic variants (CYBB, CYBA, NCF1, NCF2, NCF4) has been recognized as a direct cause of chronic granulomatous disease (CGD), an inherited immune disorder. More recently, additional diseases have been linked to functionally altered variants in genes encoding for other NADPH oxidases, such as for DUOX2/DUOXA2 in congenital hypothyroidism, or for the Nox2 complex, NOX1 and DUOX2 as risk factors for inflammatory bowel disease. A comprehensive overview of novel developments in terms of Nox/Duox-deficiency disorders is presented, combined with insights gained from structure–function studies that will aid in predicting functional defects of clinical variants.

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Deficiency in reactive oxygen species is often caused by NADPH oxidase variants.

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Overview of chronic granulomatous disease and alterations in the Nox2 complex.

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CGD iPS cells as promising novel tools.

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Risk for inflammatory bowel disease by Nox2 complex, Nox1 and Duox2 mutations.

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Loss-of-function variants in DUOX2 and DUOXA2 trigger congenital hypothyroidism.

Potential of ayurgenomics approach in complex trait research: leads from a pilot study on rheumatoid arthritis

Background

Inconsistent results across association studies including Genome-wide association, have posed a major challenge in complex disease genetics. Of the several factors which contribute to this, phenotypic heterogeneity is a serious limitation encountered in modern medicine. On the other hand, Ayurveda, a holistic Indian traditional system of medicine, enables subgrouping of individuals into three major categories namely Vata, Pitta and Kapha, based on their physical and mental constitution, referred to as Prakriti. We hypothesised that conditioning association studies on prior risk, predictable in Ayurveda, will uncover much more variance and potentially open up more predictive health.

Objectives and Methods

Identification of genetic susceptibility markers by combining the prakriti based subgrouping of individuals with genetic analysis tools was attempted in a Rheumatoid arthritis (RA) cohort. Association of 21 markers from commonly implicated inflammatory and oxidative stress pathways was tested using a case-control approach in a total cohort comprising 325 cases and 356 controls and in the three subgroups separately. We also tested few postulates of Ayurveda on the disease characteristics in different prakriti groups using clinico-genetic data.

Results

Inflammatory genes like IL1β (C-C-C haplotype, p = 0.0005, OR = 3.09) and CD40 (rs4810485 allelic, p = 0.04, OR = 2.27) seem to be the determinants in Vata subgroup whereas oxidative stress pathway genes are observed in Pitta (SOD3 rs699473, p = 0.004, OR = 1.83; rs2536512 p = 0.005; OR = 1.88 and PON1 rs662, p = 0.04, OR = 1.53) and Kapha (SOD3 rs2536512, genotypic, p = 0.02, OR = 2.39) subgroups. Fixed effect analysis of the associated markers from CD40, SOD3 and TNFα with genotype X prakriti interaction terms suggests heterogeneity of effects within the subgroups. Further, disease characteristics such as severity was most pronounced in Vata group.

Conclusions

This exploratory study suggests discrete causal pathways for RA etiology in prakriti based subgroups, thereby, validating concepts of prakriti and personalized medicine in Ayurveda. Ayurgenomics approach holds promise for biomarker discovery in complex diseases.

Association analysis of TNFR2, VDR, A2M, GSTT1, GSTM1, and ACE genes with rheumatoid arthritis in South Asians and Caucasians of East Midlands in the United Kingdom

Genetic associations of TNFR2, VDR (Bsm I and Fok I), A2M, GSTT(1), GSTM(1) and ACE in South Asian and Caucasian patients with rheumatoid arthritis (RA) were assessed in this study. DNA samples from South Asians (134 cases, 149 controls) and Caucasians (137 cases, 150 controls) from the East Midlands of the United Kingdom were genotyped for seven polymorphisms. All cases were rheumatoid-factor positive. Significant genetic associations were observed with TNFR2 R-R (OR = 3.16, CI 1.20-9.26, P < 0.05), A2M 1-1 (OR = 2.09, CI 1.21-3.64, P < 0.05) and GST T(1)null (OR = 1.97, CI 1.07-3.68, P < 0.05) among Caucasian patients. In South Asians, VDR Bsm I B-B genotype (OR = 2.08, CI 1.23-3.52, P < 0.05), A2M 2-2 genotype (OR = 3.99, CI 1.19-17.18, P < 0.05), and GST T(1)null genotype (OR = 2.81, CI 1.40-5.77, P < 0.002) genotypes were associated with RA. In the majority of cases, recessive and multiplicative modes of inheritance explained the observed associations. This study demonstrates that ethnicity affects the genetic associations in RA.