The association between three promoter polymorphisms of IL-1 and stroke: a meta-analysis

Association Between Interleukin-6 Gene Polymorphism and Severity of Coronary Artery Disease in Patients with Diabetes

Introduction

Previous studies have identified diabetes as a risk factor for coronary heart disease. This study determined the correlation between the IL-6 gene -572 G/C polymorphism and the incidence and severity of coronary heart disease in patients with diabetes.

Methods

One hundred four patients with diabetes who were admitted to our hospital from January 2019 to December 2020 were retrospectively enrolled in the current study. These patients were divided into a diabetes only group (group A, 27 patients) and a diabetes complicated by coronary heart disease group (group B, 77 patients). Seventy patients in the latter group were further divided into low, medium, and high Syntax score groups based on coronary angiography results. A correlation analysis between IL-6, blood lipids, and the IL-6 -572 G/C gene levels was performed.

Results

The serum IL-6 level in patients with the IL-6-572G/C-GG genotype was higher than patients with the GC and CC genotypes. In patients with diabetes, the presence of the IL-6-572G/C-GG and GC genotypes was associated with a significantly increased risk of developing coronary heart disease. Patients with the IL-6-572G/C-GG genotype and diabetes were shown to have more severe coronary artery lesions compared to patients with the CC genotype. Moreover, the G allele of the IL-6-572G/C gene was linked to a higher risk of coronary heart disease and more severe coronary artery lesions in patients with diabetes compared to the C allele.

Conclusion

The IL-6-572G/C gene polymorphism is associated with the incidence and severity of coronary heart disease in patients with diabetes.

Signaling pathways involved in ischemic stroke: molecular mechanisms and therapeutic interventions

Ischemic stroke is caused primarily by an interruption in cerebral blood flow, which induces severe neural injuries, and is one of the leading causes of death and disability worldwide. Thus, it is of great necessity to further detailly elucidate the mechanisms of ischemic stroke and find out new therapies against the disease. In recent years, efforts have been made to understand the pathophysiology of ischemic stroke, including cellular excitotoxicity, oxidative stress, cell death processes, and neuroinflammation. In the meantime, a plethora of signaling pathways, either detrimental or neuroprotective, are also highly involved in the forementioned pathophysiology. These pathways are closely intertwined and form a complex signaling network. Also, these signaling pathways reveal therapeutic potential, as targeting these signaling pathways could possibly serve as therapeutic approaches against ischemic stroke. In this review, we describe the signaling pathways involved in ischemic stroke and categorize them based on the pathophysiological processes they participate in. Therapeutic approaches targeting these signaling pathways, which are associated with the pathophysiology mentioned above, are also discussed. Meanwhile, clinical trials regarding ischemic stroke, which potentially target the pathophysiology and the signaling pathways involved, are summarized in details. Conclusively, this review elucidated potential molecular mechanisms and related signaling pathways underlying ischemic stroke, and summarize the therapeutic approaches targeted various pathophysiology, with particular reference to clinical trials and future prospects for treating ischemic stroke.

Interleukin-1 and Interleukin-6 Polymorphisms Might Influence Predisposition to Hemorrhagic Cerebral Vascular Diseases: A Meta-Analysis

BACKGROUND

Interleukin-1 (IL-1) and IL-6 polymorphisms might influence predisposition to hemorrhagic cerebral vascular diseases, but the results of already published studies regarding relationship between IL-1/IL-6 polymorphisms and hemorrhagic cerebral vascular diseases were still controversial and ambiguous.

OBJECTIVES

The authors designed this meta-analysis to more precisely estimate the relationship between IL-1/IL-6 polymorphisms and hemorrhagic cerebral vascular diseases by pooling the results of already published related studies.

METHODS

The authors searched PubMed, EMBASE, Web of Science, and CNKI for already published studies. Eighteen already published studies were pooled analyzed in this meta-analysis.

RESULTS

The pooled meta-analyses' results showed that distributions of IL-1A rs1800587, IL-1B rs16944, and IL-6 rs1800796 polymorphisms among patients and controls differed significantly. Moreover, distribution of the IL-6 rs1800795 polymorphism among patients and controls from Asians also differed significantly. Further analyses showed similar findings for IL-1A rs1800587, IL-1B rs16944, and IL-6 rs1800796 polymorphisms in aneurysmal subarachnoid hemorrhage (aSAH) subgroup.

CONCLUSIONS

This meta-analysis suggested that IL-1A rs1800587, IL-1B rs16944, and IL-6 rs1800796 polymorphisms might influence susceptibility to hemorrhagic cerebral vascular diseases, especially for aSAH. Moreover, IL-6 rs1800795 might influence susceptibility to hemorrhagic cerebral vascular diseases in Asians.

Clinacanthus nutans Mitigates Neuronal Death and Reduces Ischemic Brain Injury: Role of NF-κB-driven IL-1β Transcription

Neuroinflammation has been shown to exacerbate ischemic brain injury, and is considered as a prime target for the development of stroke therapies. Clinacanthus nutans Lindau (C. nutans) is widely used in traditional medicine for treating insect bites, viral infection and cancer, due largely to its anti-oxidative and anti-inflammatory properties. Recently, we reported that an ethanol extract from the leaf of C. nutans could protect the brain against ischemia-triggered neuronal death and infarction. In order to further understand the molecular mechanism(s) for its beneficial effects, two experimental paradigms, namely, in vitro primary cortical neurons subjected to oxygen-glucose deprivation (OGD) and in vivo rat middle cerebral artery (MCA) occlusion, were used to dissect the anti-inflammatory effects of C. nutans extract. Using promoter assays, immunofluorescence staining, and loss-of-function (siRNA) approaches, we demonstrated that transient OGD led to marked induction of IL-1β, IL-6 and TNFα, while pretreatment with C. nutans suppressed production of inflammatory cytokines in primary neurons. C. nutans inhibited IL-1β transcription via preventing NF-κB/p65 nuclear translocation, and siRNA knockdown of either p65 or IL-1β mitigated OGD-mediated neuronal death. Correspondingly, post-ischemic treatment of C. nutans attenuated IκBα degradation and decreased IL-1β, IL-6 and TNFα production in the ischemic brain. Furthermore, IL-1β siRNA post-ischemic treatment reduced cerebral infarct, thus mimicking the beneficial effects of C. nutans. In summary, our findings demonstrated the ability for C. nutans to suppress NF-κB nuclear translocation and inhibit IL-1β transcription in ischemic models. Results further suggest the possibility for using C. nutans to prevent and treat stroke patients.

Shared genetic risk factors for depression and stroke

BACKGROUND

The comorbidity of major depressive disorder (MDD) and stroke are common in clinic. There is a growing body of evidence suggesting a bi-directional relationship between stroke and depression. However, the mechanisms underlying the relationship between MDD and stroke are poorly investigated. Considering that both MDD and stroke can be heritable and are influenced by multiple risk genes, shared genetic risk factors between MDD and stroke may exist.

OBJECTIVE

The objective is to review the existing evidence for common genetic risk factors for both MDD and stroke and to outline the possible pathophysiological mechanisms mediating this association.

METHODS

A systematic review and meta-analysis was performed. Gene association studies regarding stroke and depression were searched in the database PubMed, CNKI, and Chinese Biomedical Literature Database before December 2018. Statistical analysis was performed using the software Revman 5.3.

RESULTS

Genetic polymorphisms of 4 genes, methylenetetrahydrofolate reductase (MTHFR) and apolipoprotein E (ApoE) have been demonstrated to associate with the increased risk for both MDD and stroke, while the association between identified polymorphisms in angiotensin converting enzyme (ACE) and serum paraoxonase (PON1) with depression is still under debate, for the existing studies are insufficient in sample size. These results suggest the possible pathophysiological mechanisms that are common to these two disorders, including immune-inflammatory imbalance, increased oxidative and nitrative stress, dysregulation of lipoprotein and lipid metabolism, and changes of cerebrovascular morphology and function. Other associated genes with few or conflicting results have also been included, and a few studies have investigated the effects of the described polymorphisms on MDD and stroke comorbidity, such as post stroke depression.

CONCLUSION

These findings suggest that shared genetic pathways may contribute to the comorbidity of MDD and stroke. Studies to evaluate the shared genetic variations between MDD and stroke may provide insights into the molecular mechanisms that trigger disease progression.

Post-stroke inflammation-target or tool for therapy?

Inflammation is currently considered a prime target for the development of new stroke therapies. In the acute phase of ischemic stroke, microglia are activated and then circulating immune cells invade the peri-infarct and infarct core. Resident and infiltrating cells together orchestrate the post-stroke inflammatory response, communicating with each other and the ischemic neurons, through soluble and membrane-bound signaling molecules, including cytokines. Inflammation can be both detrimental and beneficial at particular stages after a stroke. While it can contribute to expansion of the infarct, it is also responsible for infarct resolution, and influences remodeling and repair. Several pre-clinical and clinical proof-of-concept studies have suggested the effectiveness of pharmacological interventions that target inflammation post-stroke. Experimental evidence shows that targeting certain inflammatory cytokines, such as tumor necrosis factor, interleukin (IL)-1, IL-6, and IL-10, holds promise. However, as these cytokines possess non-redundant protective and immunoregulatory functions, their neutralization or augmentation carries a risk of unwanted side effects, and clinical translation is, therefore, challenging. This review summarizes the cell biology of the post-stroke inflammatory response and discusses pharmacological interventions targeting inflammation in the acute phase after a stroke that may be used alone or in combination with recanalization therapies. Development of next-generation immune therapies should ideally aim at selectively neutralizing pathogenic immune signaling, enhancing tissue preservation, promoting neurological recovery and leaving normal function intact.

Targeting phosphodiesterase 4 as a potential therapeutic strategy for enhancing neuroplasticity following ischemic stroke

Sensorimotor recovery following ischemic stroke is highly related with structural modification and functional reorganization of residual brain tissues. Manipulations, such as treatment with small molecules, have been shown to enhance the synaptic plasticity and contribute to the recovery. Activation of the cAMP/CREB pathway is one of the pivotal approaches stimulating neuroplasticity. Phosphodiesterase 4 (PDE4) is a major enzyme controlling the hydrolysis of cAMP in the brain. Accumulating evidences have shown that inhibition of PDE4 is beneficial for the functional recovery after cerebral ischemia; i. subtype D of PDE4 (PDE4D) is viewed as a risk factor for ischemic stroke; ii. inhibition of PDE4 enhances neurological behaviors, such as learning and memory, after stroke in rodents; iii.PDE4 inhibition increases dendritic density, synaptic plasticity and neurogenesis; iv. activation of cAMP/CREB signaling by PDE4 inhibition causes an endogenous increase of BDNF, which is a potent modulator of neuroplasticity; v. PDE4 inhibition is believed to restrict neuroinflammation during ischemic stroke. Cumulatively, these findings provide a link between PDE4 inhibition and neuroplasticity after cerebral ischemia. Here, we summarized the possible roles of PDE4 inhibition in the recovery of cerebral stroke with an emphasis on neuroplasticity. We also made some recommendations for future research.

Lack of association between interleukin-1 receptor antagonist gene 86-bp VNTR polymorphism and ischemic stroke: A meta-analysis

OBJECTIVE

The results of published studies which examined the association between variable number tandem repeat (VNTR) polymorphism of interleukin-1 receptor antagonist (IL-1RN) and ischemic stroke (IS) are conflicting. Thus, we performed a meta-analysis to examine the potential association between IL-1RN VNTR polymorphism and IS risk.

METHODS

A systematic literature search of PubMed, Embase, Medline, Web of Science, Cochrane Library, Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure, CQVIP, and WANFANG Database identified 10 studies with 2331 cases and 3335 controls. The pooled odds ratio (OR) with 95% confidence interval (95% CI) was calculated to evaluate the strength of the association. Subgroup analysis and meta-regression analysis were used to investigate the potential sources of heterogeneity. Begg funnel plots were used to explore the publication bias.

RESULTS

In this study, no enough proof was found to prove the association between IL-1RN 86-bp VNTR polymorphism and IS risk with random-effects model in the homozygous model (1/1 vs 2/2, OR = 0.97, 95% CI = 0.50-1.87, Pheterogeneity = .00), the heterozygous model (1/2 vs 2/2, OR = 0.64, 95% CI = 0.41-1.01, Pheterogeneity = .10), the dominant model (1/1 + 1/2 vs 2/2, OR = 0.85, 95% CI = 0.51-1.42, Pheterogeneity = .02), the recessive model (1/1 vs 1/2 + 2/2, OR = 0.69, 95% CI = 0.46-1.03, Pheterogeneity = .00), and allelic model (1 vs 2, OR = 1.24, 95% CI = 0.89-1.74, Pheterogeneity = .00). A marginally significant negative association was observed between IL-1RN 86-bp VNTR polymorphism and IS risk in the heterozygous model in the fixed-effects model (1/2 vs 2/2, OR = 0.71, 95% CI = 0.53-0.95, Pheterogeneity = .10). In subgroup analyses, similar association was found in the group whose control size was lower than 300.

CONCLUSION

In conclusion, our results suggested that there was no sufficient evidence to support the association between IL-1RN 86-bp VNTR polymorphism and IS. Further large epidemiologic studies need to be done to confirm these findings.

Interleukin-6 polymorphisms and risk of coronary artery diseases in a Chinese population: A case-control study

Objective:

We aimed to evaluate the relationship between IL-6-174G>C, -572G>C and -597G>A polymorphisms and development of coronary artery diseases in a Chinese population.

Methods:

A total of 275 patients with coronary artery disease and 296 healthy control subjects were collected between January 2013 and November 2014. The IL-6 genotyping for -174G>C, -592G>C and -597G>A polymorphic sites was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) according to the manufacturer instructions.

Results:

Using unconditional regression analysis, we observed that the AC and CC genotypes of IL-6 -592A>C were associated with the increased risk of developing coronary artery disease when compared with the AA genotype, and the adjusted ORs (95%CI) were 1.63(1.12-2.38) and 2.70(1.57-4.67), respectively. Additionally, the C allele of IL-6 -592A>C (OR=1.65, 95%CI=1.29-2.11) was correlated with a higher risk of developing coronary artery disease in comparison to the A allele. However, no relationship was found between IL-6-174G>C and -597G>A polymorphisms and coronary artery disease susceptibility.

Conclusion:

This study suggests that IL-6 -592G>C polymorphism is correlated with the risk of coronary artery disease. More well-designed prospective studies based on large sample size, multiple SNPs or haplotypes are required to confirm the current findings.

The association between vascular endothelial growth factor gene polymorphisms and stroke: a meta-analysis

OBJECTIVES

Numerous studies have investigated the relationships between vascular endothelial growth factor (VEGF) gene polymorphisms and stroke. However, their findings remain controversial. The objective of this study was to evaluate the relationships between VEGF gene polymorphisms and stroke by a meta-analysis.

MATERIALS AND METHODS

The PubMed, Embase, China National Knowledge Infrastructure database, Wanfang Chinese database, and VIP Chinese database were systemically searched. Data were extracted by two independent reviewers, and pooled odds ratio (OR) with 95% confidence interval (CI) were calculated.

RESULTS

Ten studies were included, including a total of 2331 cases and 1814 controls for +936C>T, 3040 cases and 2649 controls for -1154G>A. Under the dominant and recessive models, respectively, the overall ORs and 95% CIs of +936 T were 1.44, 1.09-1.90, P = 0.01 (1.53, 1.14-2.05, P = 0.005, in Asians) and 1.19, 0.85-1.65, P = 0.31, and the overall ORs and 95% CIs of -1154 A were 0.98, 0.87-1.10, P = 0.75 and 0.95, 0.82-1.11, P = 0.53. No publication bias was found in this meta-analysis.

CONCLUSIONS

The meta-analysis showed that +936C>T may be a risk factor for stroke, especially in Asians, while -1154G>A was not associated with stroke.

Genetic association between inflammatory genes (IL-1α, CD14, LGALS2, PSMA6) and risk of ischemic stroke: A meta-analysis

BACKGROUND

Sequence variations in genes involved in inflammatory system are known to contribute to the risk of cerebrovascular diseases (CVD) including stroke. Very few number of studies have been published in the context of the association between Interleukin-1α(IL-1α), CD14 cell surface glycoprotein (CD14), Galectin-2-encoding gene (LGALS2)and proteasome subunit type 6 (PSMA6) gene polymorphisms with susceptibility to ischemic stroke (IS).

OBJECTIVE

The present meta-analysis aimed to provide a comprehensive account of the association between IL-1α (-C889T and -C511T), CD14 (-C159T), LGALS2 (-C3279T) and PSMA6 (-C8G) gene polymorphisms and susceptibility to IS.

METHODS

A literature search for eligible genetic studies published before August 31, 2015 was conducted in the PubMed, Medline, EMBASE, OVID, and Google Scholar databases. Fixed or random effects models were used to estimate the Pooled Odds ratio (OR) and 95% confidence interval (CI) using RevMan 5.3 software.

RESULTS

Total 21 studies were included in our meta-analysis. No significant association was observed between IL-1α (-C889T) [OR = 1.18, 95% CI: 0.67-2.08, P = 0.58], IL-1α (-C511T) [OR = 0.95, 95% CI: 0.66-1.37, P = 0.77], LGALS2(-C2379T) [OR = 0.29, 95% CI: 0.02-4.26, P = 0.37] and CD14 (-C260T) [OR = 0.93, 95% CI: 0.77-1.11, P = 0. 42] gene polymorphisms and risk of IS. However, protective level of association was observed between PSMA6 (-C8G) gene polymorphism and susceptibility to IS under the recessive model [OR = 0.25, 95% CI: 0.08-0.72, P = 0.01].

CONCLUSION

Our meta-analysis shows that IL-1α (-C889T and -C511T), CD14 (-C159T), LGALS2 (-C3279T) and gene polymorphisms are not significantly associated with the risk of IS while PSMA6 (-C8G) gene polymorphism may play a protective role with the susceptibility of IS. Further prospective large epidemiological studies are needed to confirm these findings in different populations.