Interleukin-18 gene promoter 607A polymorphism, but not 137C polymorphism, is a protective factor for ischemic stroke in the Chinese population: A meta-analysis

Natural Compounds for SIRT1-Mediated Oxidative Stress and Neuroinflammation in Stroke: A Potential Therapeutic Target in the Future

Stroke is a fatal cerebral vascular disease with a high mortality rate and substantial economic and social costs. ROS production and neuroinflammation have been implicated in both hemorrhagic and ischemic stroke and have the most critical effects on subsequent brain injury. SIRT1, a member of the sirtuin family, plays a crucial role in modulating a wide range of physiological processes, including apoptosis, DNA repair, inflammatory response, and oxidative stress. Targeting SIRT1 to reduce ROS and neuroinflammation might represent an emerging therapeutic target for stroke. Therefore, we conducted the present review to summarize the mechanisms of SIRT1-mediated oxidative stress and neuroinflammation in stroke. In addition, we provide a comprehensive introduction to the effect of compounds and natural drugs on SIRT1 signaling related to oxidative stress and neuroinflammation in stroke. We believe that our work will be helpful to further understand the critical role of the SIRT1 signaling pathway and will provide novel therapeutic potential for stroke treatment.

Cumulative Evidence for Association Between IL-8 -251T>A and IL-18 -607C>A Polymorphisms and Colorectal Cancer Susceptibility: a Systematic Review and Meta-analysis

PURPOSE

The correlation of IL-8 and IL-18 gene polymorphisms with colorectal cancer (CRC) was investigated by previous studies, though the results remained conflicting. Thus, the meta-analysis was performed to investigate the association of IL-8 -251T>A and IL-18 -607C>A polymorphisms with CRC risk.

METHODS

A comprehensive search of the PubMed, Web of Science, CNKI, SciELO, and Wanfang databases was performed up to February 20, 2020. The strength of the associations was calculated with odds ratios (ORs) and their corresponding 95% of confidence intervals (CIs).

RESULTS

A total of 16 case-control studies including 13 studies with 3908 cases and 5005 controls on IL-8 -251T>A polymorphism and three studies with 396 cases and 560 controls on IL-18 -607C>A polymorphism were selected. Pooled data revealed that the IL-8 -251T>A and IL-18 -607C>A polymorphisms were not significantly associated with an increased risk of CRC in global population. When stratified by ethnicity, source of controls, sample size, and Hardy-Weinberg equilibrium (HWE), there were still no significant association between IL-8 -251T>A polymorphism and risk of CRC.

CONCLUSIONS

Our results revealed that the IL-8 -251T>A and IL-18 -607C>A polymorphisms were not associated with an increased susceptibility to CRC. We strongly call for further studies with larger sample sizes and different ethnicities to confirm our findings.

Investigation of The Relationship Between IL-18 (-607 C/A), IL-18 (-137 G/C) Gene Variations and Ischemic Stroke Disease Development in Thrace Region of Turkey

BACKGROUND

Ischemic stroke is a clinical condition characterized by focal or global cerebral dysfunction resulting from inhibition of brain blood flow. Genetic factors play an important role in the pathogenesis of ischemic stroke. As a result of IL-18 (-607 C/A, -137 G/C) gene variations, it is thought that binding of transcription factors may be affected and IL-18 mRNA expression can be modulated. Therefore, the purpose of our study is to investigate the roles of IL-18 (-607 C/A), IL-18 (-137 G/C) gene variations in the development of ischemic stroke in Trakya Region of Turkey.

METHODS

Our study was performed with 90 ischemic stroke patients and 89 healthy controls. Genotype distributions of IL-18 (-607 C/A, -137 G/C) gene variations were determined using polymerase chain reaction (PCR) method.

RESULTS

GC genotype and CA genotype of IL-18 (-137 G/C) and IL-18 (-607 C/A) gene variations were determined higher significantly in patent group as compared with other genotypes. However, the statistically significant difference was not determined between patients with ischemic stroke and healthy control groups in terms of IL-18 (-137 G/C) and IL-18 (-607 C/A) gene variations (p > 0,05). Allele frequencies of IL-18 (-137 G/C) and IL-18 (-607 C/A) in patient and control groups were significantly different from the Hardy-Weinberg distribution (p < .001 for all).

CONCLUSION

Although these gene variations' genotype distributions were not determined as a genetic risk factor for the development of ischemic stroke, allele frequencies of IL-18 (-137 G/C) and IL-18 (-607 C/A) in patient and control groups were significantly different from the Hardy-Weinberg distribution.

Interleukin-18 in Health and Disease

Interleukin (IL)-18 was originally discovered as a factor that enhanced IFN-γ production from anti-CD3-stimulated Th1 cells, especially in the presence of IL-12. Upon stimulation with Ag plus IL-12, naïve T cells develop into IL-18 receptor (IL-18R) expressing Th1 cells, which increase IFN-γ production in response to IL-18 stimulation. Therefore, IL-12 is a commitment factor that induces the development of Th1 cells. In contrast, IL-18 is a proinflammatory cytokine that facilitates type 1 responses. However, IL-18 without IL-12 but with IL-2, stimulates NK cells, CD4⁺ NKT cells, and established Th1 cells, to produce IL-3, IL-9, and IL-13. Furthermore, together with IL-3, IL-18 stimulates mast cells and basophils to produce IL-4, IL-13, and chemical mediators such as histamine. Therefore, IL-18 is a cytokine that stimulates various cell types and has pleiotropic functions. IL-18 is a member of the IL-1 family of cytokines. IL-18 demonstrates a unique function by binding to a specific receptor expressed on various types of cells. In this review article, we will focus on the unique features of IL-18 in health and disease in experimental animals and humans.

TGF-β1 Gene -509C/T Polymorphism and Coronary Artery Disease: An Updated Meta-Analysis Involving 11,701 Subjects

Background: The transforming growth factor-β1 (TGF-β1) gene -509C/T polymorphism has been suggested to be associated with increased coronary artery disease (CAD) risk. However, the individual studies results are still inconsistent. Objective and methods: To investigate the relationship between TGF-β1 gene -509C/T polymorphism and CAD, a meta-analysis involving 11,701 participants from 8 individual studies was conducted. The pooled odds ratios (ORs) and their corresponding 95% confidence intervals were evaluated by using random or fixed effect models. Results: A significant association between TGF-β1 gene -509C/T polymorphism and CAD was detected in the total population under allelic (OR: 1.130, 95% CI: 1.060-1.200, P = 0.0001), recessive (OR: 1.390, 95% CI: 1.100-1.750, P = 0.006), dominant (OR: 0.857, 95% CI: 0.785-0.935, P = 2.507 × 10^-4), homozygous (OR: 1.258, 95% CI: 1.098-1.442, P = 0.001), heterozygous (OR: 1.147, 95% CI: 1.046-1.257, P = 0.003), and additive genetic models (OR: 1.131, 95% CI: 1.063-1.204, P = 5.442 × 10^-5). In the subgroup analysis, there was a significant association between them in Chinese population under all of the genetic models (P < 0.05), except under the heterozygous genetic model (P > 0.05). In the Caucasian subgroup, a significant association between them was also detected under all of the genetic models (P < 0.05), except under the recessive genetic model (P > 0.05). Conclusions:TGF-β1 gene -509C/T polymorphism was significantly associated with increased CAD risk. The people with T allele of TGF-β1 gene -509C/T polymorphism might be predisposed to CAD.