Polymorphism of glutathione S-transferase M1 and T1 genes and susceptibility to psoriasis disease: A study from North India

Polymorphisms of the GCLC Gene Are Novel Genetic Markers for Susceptibility to Psoriasis Associated with Alcohol Abuse and Cigarette Smoking

The aim of this pilot study was to investigate whether single nucleotide polymorphisms (SNP) in the gene encoding the catalytic subunit of glutamate cysteine ligase (GCLC) are associated with the risk and clinical features of psoriasis. A total of 944 unrelated individuals, including 474 patients with a diagnosis of psoriasis and 470 healthy controls, were recruited for the study. Six common SNPs in the GCLC gene were genotyped using the MassArray-4 system. Polymorphisms rs648595 (OR = 0.56, 95% CI 0.35-0.90; P_perm = 0.017) and rs2397147 (OR = 0.54, 95% CI 0.30-0.98; P_perm = 0.05) were associated with susceptibility to psoriasis in males. In the male group, diplotype rs2397147-C/C × rs17883901-G/G was associated with a decreased risk of psoriasis (FDR-adjusted p = 0.014), whereas diplotype rs6933870-G/G × rs17883901-G/G (FDR-adjusted p = 0.045) showed an association with an increased disease risk in females. The joint effects of SNPs with tobacco smoking (rs648595 and rs17883901) and alcohol abuse (rs648595 and rs542914) on psoriasis risk were observed (P_perm ≤ 0.05). We also found multiple sex-independent associations between GCLC gene polymorphisms and various clinical features such as earlier disease onset, the psoriatic triad, and specific localizations of skin lesions. The present study is the first to show that polymorphisms of the GCLC gene are significantly associated with the risk of psoriasis and related to its clinical features.

Psoriasis between Autoimmunity and Oxidative Stress: Changes Induced by Different Therapeutic Approaches

Psoriasis is defined as chronic, immune-mediated disease. Regardless of the development of new therapeutic approaches, the precise etiology of psoriasis remains unknown and speculative. The aim of this review was to systematize the results of previous research on the role of oxidative stress and aberrant immune response in the pathogenesis of psoriasis, as well as the impact of certain therapeutic modalities on the oxidative status in patients with psoriasis. Complex immune pathways of both the innate and adaptive immune systems appear to be major pathomechanisms in the development of psoriasis. Oxidative stress represents another important contributor to the pathophysiology of disease, and the redox imbalance in psoriasis has been reported in skin cells and, systemically, in plasma and blood cells, and more recently, also in saliva. Current immune model of psoriasis begins with activation of immune system in susceptible person by some environmental factor and loss of immune tolerance to psoriasis autoantigens. Increased production of IL-17 appears to be the most prominent role in psoriasis pathogenesis, while IL-23 is recognized as master regulator in psoriasis having a specific role in cross bridging the production of IL-17 by innate and acquired immunity. Other proinflammatory cytokines, including IFN-γ, TNF-α, IL-1β, IL-6, IL-22, IL-26, IL-29, or IL-36, have also been reported to play important roles in the development of psoriasis. Oxidative stress can promote inflammation through several signaling pathways. The most noticeable and most powerful antioxidative effects exert various biologics compared to more convenient therapeutic modalities, such as methotrexate or phototherapy. The complex interaction of redox, immune, and inflammatory signaling pathways should be focused on further researches tackling the pathophysiology of psoriasis, while antioxidative supplementation could be the solution in some refractory cases of the disease.

Role of ABCB1 and glutathione S-transferase gene variants in the association of porphyria cutanea tarda and human immunodeficiency virus infection

In Argentina, porphyria cutanea tarda (PCT) is strongly associated with infection with human immunodeficiency virus (HIV); however, whether the onset of this disease is associated with HIV infection and/or the antiretroviral therapy has not been determined. The ABCB1 gene variants c.1236C>T, c.2677G>T/A and c.3435C>T affect drug efflux. The GSTT1 null, GSTM1 null and GSTP1 (c.313A>G) gene variants alter Glutathione S-transferase (GST) activity, modifying the levels of xenobiotics. The aim of the present study was to evaluate the role of genetic variants in initiation of PCT and to analyze the genetic basis of the PCT-HIV association. Control individuals, and HIV, PCT and PCT-HIV patients were recruited, PCR-restriction fragment length polymorphism was used to genotype the ABCB1 and GSTP1 variants, and multiplex PCR was used to study the GSTM1 and GSTT1 variants. The high frequency of c.3435C>T (PCT and PCT-HIV) and c.1236C>T (PCT) suggested that the onset of PCT were not specifically related to HIV infection or antiretroviral therapy for these variants. c.2677G>T/A frequencies in the PCT-HIV patients were higher compared with the other groups, suggesting that a mechanism involving antiretroviral therapy served a role in this association. PCT-HIV patients also had a high frequency of GSTT1 null and low frequency for GSTM1 null variants; thus, the genetic basis for PCT onset may involve a combination between the absence of GSTT1 and the presence of GSTM1. In conclusion, genes encoding for proteins involved in the flow and metabolism of xenobiotics may influence the PCT-HIV association. The present study is the first to investigate the possible role of GST and ABCB1 gene variants in the triggering of PCT in HIV-infected individuals, to the best of our knowledge, and may provide novel insights into the molecular basis of the association between PCT and HIV.

Uncovering the mechanism of Jueyin granules in the treatment of psoriasis using network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Our clinical practice demonstrated that Jueyin granules (JYG) benefit patients with mild to moderate psoriasis vulgaris without apparent adverse effects. JYG have been shown to inhibit epidermal proliferation in an imiquimod (IMQ)-induced psoriasis-like mouse model, as well as keratinocyte proliferation. Moreover, JYG causes no acute or chronic toxicity in animal models. However, its related molecular mechanism has still not been elucidated.

AIM OF THE STUDY

To assess the mechanism of JYG against psoriasis.

MATERIALS AND METHODS

This study combined network pharmacology analysis with experiments to investigate the mechanism of JYG against psoriasis. First, the molecular docking technology was used to construct the network of medicinal materials-core active plant ingredients-core targets and identify possible drug targets. Next, high-performance liquid chromatography (HPLC) was used for quality control of JYG. Finally, a mice model of psoriasis was used to further verify the effects of JYG.

RESULTS

(1) Molecular docking analysis of network pharmacology revealed that the therapeutic effects of JYG on psoriasis might be achieved through Vitamin D Receptor (VDR) effects. (2) The concentrations of chlorogenic acid and paeoniflorin were determined using HPLC to establish quality control of JYG. (3) JYG ameliorated pathological characteristics that included in vivo reductions in erythema, scale, and infiltration scores of back and ear lesions in IMQ-induced psoriasis-like mice. Moreover, a reduced number of PCNA-positive and Ki67-positive cells were observed in the epidermis of JYG-treated lesions. JYG also reduced inflammation (interleukin (IL)-17, IL-23) in the peripheral blood of IMQ-induced psoriasis-like mice. As expected, JYG was found to upregulate VDR expression and downregulate p-STAT3 expression in the IMQ group, which may contribute to its mechanism against psoriasis.

CONCLUSION

Overall, this study clarifies the mechanism of JYG against psoriasis and provides evidence to support its clinical use.

Association of Genetic Polymorphisms in GSTP1, GSTM1, and GSTT1 Genes with Vesicoureteral Reflux Susceptibility in the Children of Southeast Iran

Background:

Vesicoureteral reflux (VUR) disease is the most common type of urinary tract anomalies in children. Genetic risk factors may be associated with the etiology of VUR. The role of the Glutathione S-transferases (GSTs) as multifunctional enzymes is cellular oxidative stress handling. This is the first study aimed at evaluating the relative risk of GSTP1, GSTM1, and GSTT1 polymorphisms in VUR susceptibility in children and provides new important insights into the genetics of affected children.

Methods:

The study was done in 2013 in Sistan and Baluchestan University, eastern Iran. Genotyping of three GSTP1, GSTM1, and GSTT1 genes were determined using the multiplex polymerase chain reaction assay in 216 reactions for 72 VUR children and 312 reactions for 104 healthy controls.

Results:

The presence of GSTT1 deletion was associated with high risk of VUR in children, whereas GSTP1 and GSTM1 genotypes did not show the same effect. Furthermore, the combination of GSTT1/GSTM1 and GSTT1/ GSTP1 genotypes showed a significant influence on lower risk of VUR in children.

Conclusion:

Deletion of GSTT1 functional gene is a genetic risk factor causing VUR in children. Interestingly, the combination of GSTM1 and GSTP1 null genotypes with GSTT1 has shown a protective role against risk of GSTT1 deletion.

The influence of GSTT/GSTM null genotypes in scarring

Background and aims

The process of scarring is a common denominator of interest for the medical field. From general medicine to dentistry, pathological scar tissue represents a challenge in providing optimal care to a patient. The present study aims to investigate whether a systemically reduced antioxidant potential, revealed by null isoforms of glutathione S transferase, affects the process of scarring in a group of female patients.

Methods

The study is based on a group of 54 patients with physiological scars after a 6-month observation period, as well as 18 patients with hypertrophic or atrophic scars. Peripheral venous blood was collected, from which DNA was extracted using a commercial kit. Genotyping followed a Multiplex PCR protocol for GSTT1/GSTM1.

Results

In a dominant model, the combination of wild type (heterozygous or homozygous) GSTT1 and GSTM1 was negatively associated with pathological scarring, with the wild type (heterozygous or homozygous) GSTM1 genotype being potentially responsible for this effect. Other factors affecting pathological scarring were investigated: family history, phototype, as well as scores on the POSAS and SCAR scales.

Conclusions

The presence of GSTT1 and GSTM1 alleles brings forward an increased antioxidant capacity, serving as a protective factor for patients during scar formation.

Association between genetic polymorphisms of glutathione S-transferase M1/T1 and psoriasis in a population from the area of the strict of messina (Southern Italy)

Glutathione S-transferases (GST) are antioxidant enzymes with frequent genetic polymorphisms. Homozygosis for gene deletion ("null" genotype) of GSTM1 and GSTT1, causing decrease of the antioxidant potential of the organism, is frequent, with variable frequency in different ethnic contexts. Although oxidative stress notoriously plays a role in the pathogenesis of psoriasis, few studies exist on the association between GSTM1/GSTT1 genotype and psoriasis, with different results. We aimed to assess the frequency of GSTM1/GSTT1 polymorphisms in Southern Italian psoriatic patients and controls and investigate the association of the GSTM1/GSTT1 genotype with individual and disease parameters. To this aim, the GSTM1/GSTT1 genotype of 148 psoriatic patients and 148 age- and sex-matched controls was defined by PCR on oral mucosa cells. GSTT1 null was associated with psoriasis (55.4% of patients vs. 25% of controls, p = 9.58 × 10^-8, odds ratio 3.73), while GSTM1 null was not. The GSTM1/GSTT1 "double null" genotype conferred an even higher odds ratio for psoriasis (5.94). The association between psoriasis and GSTT1 null was stronger in women (54.1% of patients vs. 19.7% of controls, p = 8.13 × 10^-5) than in men (56.3% of patients vs. 28.7% of controls, p = 0.0002). No association was found between GSTM1/GSTT1 genotype and psoriasis severity, age of onset or comorbidities (psoriatic arthritis, metabolic syndrome). The remarkable differences among the few available data on the association between GSTM1/GSTT1 polymorphisms and psoriasis suggest the need for further studies, on different and larger populations, to improve knowledge on the pathogenesis of psoriasis and possibly provide more precise and personalised prevention and treatment in the future.

Pathophysiological Alterations of Redox Signaling and Endocannabinoid System in Granulocytes and Plasma of Psoriatic Patients

Inflammatory granulocytes are characterized by an oxidative burst, which may promote oxidative stress and lipid modification both in affected tissues and on a systemic level. On the other hand, redox signaling involving lipid peroxidation products acting as second messengers of free radicals play important yet not fully understood roles in the pathophysiology of inflammation and various stress-associated disorders. Therefore, the aim of this study was to evaluate the onset of oxidative stress and alterations of enzyme-dependent lipid metabolism resulting from redox imbalance in granulocytes and plasma obtained from patients with psoriasis vulgaris or psoriatic arthritis in comparison to the healthy subjects. The results obtained revealed enhanced activity of pro-oxidant enzymes nicotinamide adenine dinucleotide phosphate (NADPH) and xanthine oxidases in granulocytes with a decrease of enzymatic and non-enzymatic antioxidants in the plasma of psoriatic patients. The nuclear factor erythroid 2–related factor 2 (Nrf2) and its regulators were increased in both forms of psoriasis while heme oxygenase 1 levels were increased only in psoriasis vulgaris. The redox imbalance was associated with decreased levels of phospholipids and of free polyunsaturated fatty acids but with enhanced activity of enzymes involved in lipid metabolism (phospholipase A2, acetylhydrolase PAF, cyclooxygenases 1 and 2) and increased lipid peroxidation products 4-hydroxynonenal, isoprostanes, and neuroprostanes. Increased endocannabinoids and G protein-coupled receptor 55 were observed in both forms of the disease while expression of the cannabinoid type 1 receptor (CB1) was increased only in patients with psoriatic arthritis, which is opposite to the cannabinoid type 2 receptor. This receptor was increased only in psoriasis vulgaris. Changes in protein expression promoted the apoptosis of granulocytes by increased caspases mainly in psoriasis vulgaris. This study indicates that inhibition of the Nrf2 pathway in psoriatic arthritis promotes a redox imbalance. In addition, increased expression of CB1 receptors leads to increased oxidative stress, lipid modifications, and inflammation, which, in turn, may promote the progression of psoriasis into the advanced, arthritic form of the disease.