Analysis of manganese superoxide dismutase (MnSOD Ala-9Val) and glutathione peroxidase (GPx1 Pro 198 Leu) gene polymorphisms in psoriasis

Selenium and Arsenic Levels, Prevalence of Common Variants of Genes Involved in Their Metabolism, and Psoriasis Disease

Using an Inductively Coupled Plasma Mass Spectrometer we measured the concentration of selenium and arsenic in serum and blood samples from 336 unselected psoriatic patients and 336 matched healthy controls to evaluate any associations with the clinical course of the disease. We genotyped 336 patients and 903 matched controls to evaluate the prevalence of SOD2 (rs4880), CAT (rs1001179), GPX1 (rs1050450), and DMGDH (rs921943) polymorphisms using Taqman assays. The mean selenium (Se) level in serum was 74 µg/L in patients and 86 µg/L in controls (p < 0.001). The mean Se level in blood was 95 µg/L in patients and 111 µg/L in controls (p < 0.001). Psoriasis risk was greatest among participants with the lowest serum (<68.75 µg/L, OR: 8.30; p < 0.001) and lowest blood concentrations of Se (<88.04 µg/L, OR: 10.3; p < 0.001). Similar results were observed in subgroups of males and females. We found an inverse correlation of selenium levels with PASI, NAPSI, and BSA scores. There was no significant difference in the distribution of the CAT, GPX1, DMGDH, and SOD2 polymorphisms. Among carriers of rs4880, rs1001179, and rs921943 polymorphisms, blood selenium levels were significantly lower. The mean arsenic level in serum was 0.79 µg/L in patients and 0.7 µg/L in controls (p = 0.2). The mean concentration in blood was 1.1 µg/L in patients and 1.3 µg/L in controls (p < 0.001). In conclusion, we found that lower selenium levels, in blood and serum, are associated with psoriasis risk and its more severe course. Future prospective studies should focus on the optimalisation of the concentration of this trace element not only for prophylactic guidance but also to support the treatment of this disease.

Circulating glutathione peroxidase and superoxide dismutase levels in patients with epilepsy: A meta-analysis

PURPOSE

Glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) are assessed as oxidative stress markers to determine the impact of oxidation on the levels of GSH-Px and SOD in patients with epilepsy (PWE) and healthy controls.

METHODS

A meta-analysis was completed on twenty-nine published studies. A total of 636 PWE and 665 healthy controls, 303 PWE and 191 controls, and 22 PWE and 22 controls were included to study GSH-Px levels in erythrocytes, serum and plasma, respectively. For SOD studies, there were 610 PWE and 680 controls, 464 PWE and 382 controls, and 62 PWE with 77 controls for erythrocytes, serum and plasma, respectively.

RESULTS

Meta-analysis showed that the erythrocyte SOD level was significantly lower in PWE than in healthy controls (SMD =-1.96; 95% CI [-2.93, -0.99]; P<0.0001). Moreover, the meta-analysis demonstrated that in serum and plasma, SOD levels in PWE were significantly lower than those in healthy controls (SMD =-1.47; 95% CI [-2.47, -0.48]; P<0.0001). Erythrocyte GSH-Px levels had a tendency to decrease in PWE compared with healthy controls (SMD =-0.31; 95% CI [-1.48, 0.85]; P=0.598), but the results showed no significant difference.

CONCLUSION

Our results showed reduced SOD levels in erythrocytes, serum and plasma in PWE, which may be an indicator of oxidative damage in epilepsy. This is the first meta-analysis of circulating GSH-Px and SOD levels in PWE and healthy controls.

Single-Nucleotide Polymorphisms and Markers of Oxidative Stress in Healthy Women

Purpose

There is accumulating evidence that oxidative stress is an important contributor to carcinogenesis. We hypothesized that genetic variation in genes involved in maintaining antioxidant/oxidant balance would be associated with overall oxidative stress.

Methods

We examined associations between single nucleotide polymorphisms (SNPs) in MnSOD, GSTP1, GSTM1, GPX1, GPX3, and CAT genes and thiobarbituric acid-reactive substances (TBARS), a blood biomarker of oxidative damage, in healthy white women randomly selected from Western New York (n = 1402). We used general linear models to calculate age-adjusted geometric means of TBARS across the variants. We also examined the associations within strata of menopausal status.

Results

For MnSOD, being heterozygous was associated with lower geometric means of TBARS (less oxidative stress), 1.28 mg/dL, compared to homozygous T-allele or homozygous C-allele,1.35 mg/dL, and 1.31 mg/dL correspondingly (p for trend = 0.01). This difference remained among postmenopausal women, 1.40 mg/dL for TT, 1.32 mg/dL for TC, and 1.34mg/dL for CC (p for trend 0.015); it was attenuated among premenopausal women. SNPs in the other genes examined (GSTP1, GSTM1, GPX1, GPX3, and CAT) were not associated with TBARS.

Conclusions

Our findings suggest that genetic variation in MnSOD gene may be associated with oxidative status, particularly among postmenopausal women.

A manganese superoxide dismutase (MnSOD) from ark shell, Scapharca broughtonii: Molecular characterization, expression and immune activity analysis

Manganese superoxide dismutase (MnSOD) is one of the key members of the antioxidant defense enzyme family, however, data regarding to the immune function of MnSOD in mollusks still remain limited now. In this study, a full-length MnSOD cDNA was identified by rapid amplification of cDNA ends (RACE) method from cDNA library of ark shell Scapharca broughtonii (termed SbMnSOD). The cDNA contained an open reading frame (ORF) of 696 bp which encoded a polypeptide of 232 amino acids, a 5'-UTR with length of 32 bp and a 3'-UTR of 275 bp. Four putative amino acid residues (His-57, His-105, Asp-190 and His-194) responsible for manganese coordination were located in the most highly conserved regions of SbMnSOD and the signature sequence (DVWEHAYY) also existed in SbMnSOD. The deduced amino acid sequence of SbMnSOD shared high homology to MnSOD from other species. All those data revealed that the SbMnSOD was a novel member of the MnSOD family. The mRNA expression profiles of SbMnSOD in tissues of foot, gill, mantle, adductor muscle, hemocytes and hepatopancreas analyzed by quantitative real-time PCR (qRT-PCR) suggested the mRNA transcripts of SbMnSOD distributed in all the examined tissues. Importantly, Vibrio anguillarum challenge resulted in the increased expression of SbMnSOD mRNA with a regular change trend in all examined tissues, indicating SbMnSOD actively participated in the immune response process. What's more, further analysis on the antibacterial activity of the recombinant SbMnSOD showed that the fusion protein could remarkably inhibit growth of both Gram-positive and Gram-negative bacteria. The present results clearly suggested that SbMnSOD was an acute phase protein involved in the immune reaction in S. broughtonii.