Polymorphisms in proinflammatory cytokines genes and susceptibility to Multiple Sclerosis

Advancing personalized medicine in neurodegenerative diseases: The role of epigenetics and pharmacoepigenomics in pharmacotherapy

About 80 % of brain disorders have a genetic basis. The pathogenesis of most neurodegenerative diseases is associated with a myriad of genetic defects, epigenetic alterations (DNA methylation, histone/chromatin remodeling, miRNA dysregulation), and environmental factors. The emergence of new sequencing technologies and tools to study the epigenome has led to identifying predictive biomarkers for earlier diagnosis, opening up the possibility of prophylactical interventions. As a result, advances in pharmacogenetics and pharmacoepigenomics now allow for personalized treatments based on the profile of each patient and the specific genetic and epigenetic mechanisms involved. This Review highlights the complexity of neurodegenerative diseases and the variability in patient responses to pharmacotherapy, emphasizing the influence of genetic polymorphisms on the pharmacokinetics and pharmacodynamics of drugs used to treat those conditions. We specifically discuss the potential modulatory effect of several genetic polymorphisms associated with an increased risk of developing different neurodegenerative diseases. We explore genetic and genomic technologies and the potential of analyzing individual-specific drug metabolism to predict and influence drug response and associated clinical outcomes. We also provide insights into the mechanism of action of the drugs under investigation and their potential impact on disease-modifying pathways. Finally, the Review underscores the great potential of this field to enhance the effectiveness and safety of drug treatments through personalized medicine.

TNF-alfa Gene Polymorphism Associations with Multiple Sclerosis

Background:TNF-α has a dual role in multiple sclerosis (MS), contributing to both protective and harmful effects. It activates immune cells, promotes the formation of inflammatory lesions in the central nervous system, and stimulates the production of other pro-inflammatory cytokines and chemokines, leading to myelin destruction and neuronal damage. Our research focused on investigating the relationship between TNF-alpha (rs1800630, rs1800629, and rs361525) gene polymorphisms and MS. Methods: 250 healthy controls and 250 multiple sclerosis (MS) patients were included in the study. DNA was extracted from leucocytes from peripheral venous blood by salt precipitation. Single nucleotide polymorphisms (SNPs) were tested using RT-PCR. Statistical analysis of the data was performed using IBM SPSS Statistics 29.0 data analysis software. Results: The analysis revealed that the rs361525 AG genotype was significantly less frequent in the MS group compared to the control group (4.0% vs. 7.2%, p = 0.042). Sex-specific analysis showed a significant difference in genotype distribution (GG, AG, AA) among males between the MS group and the control group (97.7%, 0%, 2.3% vs. 90.6%, 9.4%, 0%, p = 0.005). For the rs1800629 polymorphism, significant results were also found. In subjects younger than 39 years, the A allele was significantly less frequent in the MS group than in the control group (8.6% vs. 15.0%, p = 0.030). The most robust model indicated that the AA genotype reduced the odds of MS by approximately 2 fold compared to the AG + GG genotype (p = 0.044), and each A allele reduced the odds of MS by approximately 2 fold (p = 0.028). The rs1800630 A allele was significantly more common in males in the MS group than in the control group (21.0% vs. 12.9%, p = 0.046). Conclusions: In conclusion, our study identifies significant associations between TNF-alpha gene variants and MS. Specifically, the rs631525 AG genotype was less common in the MS group, with notable sex-specific differences observed. The rs1800629 A allele was statistically significantly less frequent in the MS group than in the control group, and the AA genotype reduced the odds of MS occurrence by ~2 fold compared with the AG + GG genotypes. Additionally, each A allele of rs1800629 was linked to a 2-fold decreased odds of MS occurrence. In males, the rs1800630 A allele was more frequent in the MS group. These findings highlight the relevance of TNF-alpha genetic variations in MS susceptibility, suggesting potential avenues for further research and therapeutic exploration.

Association between polymorphisms in TLR3, TICAM1 and IFNA1 genes and covid-19 severity in Southern Brazil

BACKGROUND

A distinct phenotype in Coronavirus disease 2019 (Covid-19) was observed in severe patients, consisting of a highly impaired interferon (IFN) type I response, an exacerbated inflammatory response.

OBJECTIVE

The aim of the present study was to investigate a possible association of single nucleotide polymorphisms (SNPs), in five genes related to the immune response, rs3775291 in TLR3; rs2292151 in TICAM1; rs1758566 in IFNA1; rs1800629 in TNF, and rs1800795 in IL6 with the severity of Covid-19.

METHODS

A cross-sectional study was performed, with non-severe and severe/critical patients diagnosed with Covid-19, by two public hospitals in Brazil. In total, 300 patients were genotyped for the SNPs, 150 with the non-severe form of the disease and 150 with severe/critical form.

RESULTS

The T/T genotype of TLR3 in recessive model shows 58% of protection against severe/critical Covid-19; as well as the genotypes G/A+A/A of TICAM1 in dominant model with 60% of protection, and in a codominant model G/A with 57% and A/A with 71% of protection against severe/critical Covid-19. Comparing severe and critical cases, the T/C genotype of IFNA1 in the codominant model and TC+C/C in the dominant model showed twice the risk of critical Covid-19.

CONCLUSION

We can conclude that rs3775291, rs2292151 and rs1758566 can influence the COVID-19 severity.

Multiple Sclerosis: New Insights into Molecular Pathogenesis and Novel Platforms for Disease Treatment

BACKGROUND

Multiple sclerosis (MS), a chronic inflammatory disorder, affects the central nervous system via myelin degradation. The cause of MS is not fully known, but during recent years, our knowledge has deepened significantly regarding the different aspects of MS, including etiology, molecular pathophysiology, diagnosis and therapeutic options. Myelin basic protein (MBP) is the main myelin protein that accounts for maintaining the stability of the myelin sheath. Recent evidence has revealed that MBP citrullination or deamination, which is catalyzed by Ca2+ dependent peptidyl arginine deiminase (PAD) enzyme leads to the reduction of positive charge, and subsequently proteolytic cleavage of MBP. The overexpression of PAD2 in the brains of MS patients plays an essential role in new epitope formation and progression of the autoimmune disorder. Some drugs have recently entered phase III clinical trials with promising efficacy and will probably obtain approval in the near future. As different therapeutic platforms develop, finding an optimal treatment for each individual patient will be more challenging.

AIMS

This review provides a comprehensive insight into MS with a focus on its pathogenesis and recent advances in diagnostic methods and its present and upcoming treatment modalities.

CONCLUSION

MS therapy alters quickly as research findings and therapeutic options surrounding MS expand. McDonald's guidelines have created different criteria for MS diagnosis. In recent years, ever-growing interest in the development of PAD inhibitors has led to the generation of many reversible and irreversible PAD inhibitors against the disease with satisfactory therapeutic outcomes.

Cytokine polymorphisms in patients with autoimmune hemolytic anemia

Autoimmune hemolytic anemia (AIHA) is due to autoantibodies with or without complement activation and involves cellular and cytokine dysregulation. Here, we investigated cytokine single-nucleotide polymorphisms (SNPs) of TNF-α, TGF-β1, IL-10, IL-6, and IFN-γ, along with their serum levels. The former were related to hematological parameters, therapy, and clinical outcome. The study included 123 consecutive patients with primary AIHA [77 warm AIHA and 46 cold agglutinin disease (CAD)], followed up for a median of 49 months. Results show that the allelic frequency of TNF-α -308 G/A polymorphisms was significantly lower in patients versus controls. Moreover, the genotypic frequency of TNF-α -308G/A and TGF-β gene codon 25 G/C genotypes was significantly lower in patients versus controls. Considering cytokine SNP genotypes associated with different gene expression levels, TNF-α high gene expression was significantly more frequent in patients, TGF-β and IL-10 high gene expression was higher in patients with more severe anemia, and TGF-β high gene expression was higher in patients with active disease. Considering treatment, TNF-α and TGF-β high gene expression was more frequent in multitreated patients and particularly in CAD. It may be speculated that this genetic predisposition to a stronger inflammatory response may result in a greater immune dysregulation and in a relapsed/refractory disease. Regarding cytokine serum levels, TNF-α and TGF-β were significantly lower, and IL-10 and IL-6 were significantly higher in patients versus controls, underlying the complex interplay between genetic background and disease features.

Interleukin-16 genetic polymorphisms in Guangxi Chinese with hepatitis B virus-related liver cirrhosis

BACKGROUND

Our previous study has reported that interleukin-16 (IL-16) genetic polymorphisms are significantly related to chronic hepatitis B (CHB) and hepatitis B virus-related (HBV-related) hepatocellular carcinoma (HCC). As CHB, liver cirrhosis (LC), and HCC are development processes, this study aimed to determine genetic correlation of IL-16 polymorphisms with HBV-related LC in a Chinese population.

METHODS

IL-16 gene rs11556218, rs4072111, and rs4778889 polymorphism in 129 patients with HBV-related LC and 168 healthy individuals were genotyped via polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). PCR-RFLP results were verified by DNA sequencing.

RESULTS

The allelic and genotypic distributions of IL-16 rs11556218, rs4072111, and rs4778889 polymorphisms in HBV-related LC patients showed no significant difference from those in healthy controls. Furthermore, no relationship was observed between the haplotype distribution and susceptibility to HBV-related LC.

CONCLUSIONS

This work provided the first evidence that the IL-16 genetic polymorphisms may not be associated with HBV-related LC risk.

Lack of association between TNFA and TNFB polymorphisms and the risk of multiple sclerosis: a meta-analysis from 37 studies

BACKGROUND

Epidemiological studies about the association between genetic polymorphisms in TNFA, TNFB, and IFNG and the risk for multiple sclerosis (MS) have been performed extensively. However, the results are inconclusive. The purpose of this meta-analysis was to evaluate the contribution of the polymorphisms in TNFA, TNFB, and IFNG to the susceptibility of MS.

METHODS

The PubMed, Web of Science, and China National Knowledge Infrastructure databases were searched to identify relevant studies up to October 2021. A meta-analysis was performed and pooled odds ratios (OR) and confidence intervals (CI) were computed using fixed or random effects models.

RESULTS

A marginally significant association of the IFNG +874AT genotype with high risk of MS was observed in a heterozygous comparison (OR = 1.51, 95% CI, 1.02-2.23). However, no significant association between the TNFA (-308G/A, -238G/A, and -376G/A) and TNFB +252A/G polymorphisms and MS risk was observed both in overall analysis and in subgroup analysis.

CONCLUSION

This meta-analysis provides evidence that the TNFA (-308G/A, -238G/A, and -376G/A) and TNFB +252A/G polymorphisms were not risk factors for the occurrence of MS. Further studies with larger samples are necessary to reach the concise results about the contribution of other polymorphisms to the risk of MS.

Toll-like receptor 10 gene polymorphism and risk of multiple sclerosis among Iraqi patients

Background

Toll-like receptors (TLRs) are a family of 10 pattern recognition receptors (TLR1–TLR10) involved in the regulation of inflammatory and immune responses besides their role in the pathogenesis of autoimmune diseases including multiple sclerosis (MS). TLR10 is the least studied TLR in MS, and data for single nucleotide polymorphisms (SNPs) of the TLR10 gene are limited. Therefore, a case–control study was performed on 85 patients with relapsing–remitting MS and 86 healthy controls (HC) to explore SNPs in the promoter region of TLR10 gene. A 927-bp region was amplified, and Sanger sequencing identified 10 SNPs with a minor allele frequency ≥ 10% (rs200395112 T/A, rs201802754 A/T, rs201228097 T/A, rs113588825 G/A, rs10004195 T/A, rs10034903 C/G, rs10012016 G/A/C, rs10012017 G/T, rs33994884 T/Deletion [Del] and rs28393318 A/G).

Results

Del allele and T/Del genotype of rs33994884, as well as AG genotype of rs28393318, showed significantly lower frequencies in MS patients compared to HC. Allele and genotype frequencies of the 10 SNPs showed no significant differences between MS patients classified according to the Expanded Disability Status Scale. Haplotype analysis revealed that haplotype A-T-A-G-A-G-G-T-A showed a significantly increased frequency in MS patients compared to HC (odds ratio [OR] = 9.70; 95% confidence interval [CI] = 1.28–73.31; corrected probability [pc] = 0.03), while frequency of A-T-A-G-T-C-A-T-G haplotype was significantly decreased (OR = 0.10; 95% CI = 0.01–0.85; pc = 0.05).

Conclusions

The study indicated that two SNPs may influence susceptibility to MS (rs33994884 and rs28393318), but haplotype analysis of TLR10 gene SNPs was more informative.