A Polymorphism Within the 3'UTR of NLRP3 is Associated with Susceptibility for Ischemic Stroke in Chinese Population

The gain-of-function variant in the NLRP3 gene predicts the effectiveness of brief psychotherapy but not the risk of major depression

Major depressive disorder (MDD) is a highly prevalent psychiatric condition whose pathophysiology has been linked to neuroinflammatory processes involving the NLRP3 inflammasome. To address this point, the study investigated the association of the NLRP3 rs10754558 polymorphism with MDD diagnosis in a young adults population based study and the effectiveness of brief psychotherapies in a randomized clinical trial. A cross-sectional, population-based study was conducted with 1100 individuals aged 18-35 years, including 615 controls and 485 patients with MDD. Diagnosis was determined using the Mini International Neuropsychiatric Interview (M.I.N.I.) based on DSM-IV criteria. Our clinical trial included 227 participants with MDD aged 18-60 years from a randomized clinical trial evaluating the effectiveness of two brief psychotherapies for MDD. Depressive and anxiety symptoms were assessed at baseline, post-treatment (16-18 weeks), and 6-month follow-up using the Beck Depression Inventory-II (BDI-II) and the Beck Anxiety Inventory (BAI). Statistical analyses included logistic regression and generalized estimating equation (GEE) model adjusted for demographic and clinical variables. The results showed no significant association between rs10754558 genotypes and MDD diagnosis. However, when evaluating the efficacy of brief psychotherapies, the GG genotype was associated with poorer treatment outcomes for both depressive and anxiety symptoms compared to the GC/CC genotypes (p < 0.05). Longitudinal analysis revealed significant differences over time, with GG individuals demonstrating less symptom improvement (BDI-II: baseline 36.61 to follow-up 21.75; BAI: baseline 26.32 to follow-up 19.55) compared to GC/CC genotypes (BDI-II: baseline 32.05 to follow-up 20.29; BAI: baseline 22.05 to follow-up 17.96). These findings suggest that the GG genotype, previously characterized as a gain-of-function variant, may contribute to genetic heterogeneity influencing psychotherapy outcomes. This highlights the potential for genetic markers, such as rs10754558, to inform personalized psychiatric treatments and improve therapeutic strategies.

Association and interaction analysis of NLRP3 gene polymorphisms with hypertension risk: a case-control study in China

BACKGROUND

The NLRP3 inflammasome, a pivotal mechanism regulating inflammatory responses and featuring the pyrin domain containing 3 (NLRP3) within the NOD-like receptor family, is widely recognized as a central pathogenic factor in cardiovascular diseases. The present study endeavors to delve into the correlation and potential interplay between the rs10754558 polymorphism of NLRP3 and the predisposition to hypertension among the Chinese adult population.

METHODS

All the participants who came from a community in Bengbu, China were investigated by being interviewed with a questionnaire. Overall, 354 paired case-control participants were analyzed. Genomic DNA was extracted from 5ml venous blood using the Tiangen DNA extraction kit. The rs10754558 polymorphism of the NLRP3 gene was genotyped by TaqMan allelic discrimination real-time PCR.The association between the rs10754558 polymorphism and hypertension risk was investigated by a logistic regression analysis. Furthermore, an additive interaction analysis was conducted using related indicators, including the relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP), and synergy index (SI).

RESULTS

Participants carrying the GG genotype were more likely to develop hypertension than participants carrying the CC genotype (adjusted odds ratio [OR]: 2.16, 95% confidence interval [CI]: 1.33-3.52). A significant additive interaction between the NLRP3 polymorphism and obesity status concerning the risk of hypertension was observed, as estimated by all indicators: RERI (1.12, 95% CI: 0.70-1.5), AP (0.34, 95% CI: 0.14-0.53), and SI (1.92, 95% CI: 1.03-3.59). The values of RERI (1.74, 95% CI: 0.37-3.11), AP (0.46, 95% CI: 0.21-0.70), and SI (2.62, 95% CI: 1.18-5.83) showed that a significant interaction between the rs10754558 polymorphism and a family history of hypertension.

CONCLUSIONS

Our findings indicate a significant association between the NLRP3 rs10754558 polymorphism and the risk of hypertension in Chinese adults. Moreover, a notable additive interaction emerges between NLRP3 polymorphisms and obesity status, further amplifying the risk of hypertension.

Neuroprotection or Sex Bias: A Protective Response to Traumatic Brain Injury in the Females

Traumatic brain injury (TBI) is a major healthcare problem and a common cause of mortality and morbidity. Clinical and preclinical research suggests sex-related differences in short- and longterm outcomes following TBI; however, males have been the main focus of TBI research. Females show a protective response against TBI. Female animals in preclinical studies and women in clinical trials have shown comparatively better outcomes against mild, moderate, or severe TBI. This reflects a favorable protective nature of the females compared to the males, primarily attributed to various protective mechanisms that provide better prognosis and recovery in the females after TBI. Understanding the sex difference in the TBI pathophysiology and the underlying mechanisms remains an elusive goal. In this review, we provide insights into various mechanisms related to the anatomical, physiological, hormonal, enzymatic, inflammatory, oxidative, genetic, or mitochondrial basis that support the protective nature of females compared to males. Furthermore, we sought to outline the evidence of multiple biomarkers that are highly potential in the investigation of TBI's prognosis, pathophysiology, and treatment and which can serve as objective measures and novel targets for individualized therapeutic interventions in TBI treatment. Implementations from this review are important for the understanding of the effect of sex on TBI outcomes and possible mechanisms behind the favorable response in females. It also emphasizes the critical need to include females as a biological variable and in sufficient numbers in future TBI studies.

Ischemic Preconditioning Provides Neuroprotection by Inhibiting NLRP3 Inflammasome Activation and Cell Pyroptosis

Increasing evidence has demonstrated that ischemic preconditioning (IPC) increases cerebral tolerance to subsequent prolonged ischemic insults. However, the exact mechanisms underlying the process have not been fully explored. In the current study, we aim to investigate whether NLRP3 inflammasome and cell pyroptosis are involved in the neuroprotective mechanism of IPC after ischemic stroke. In vitro, IPC was set up by exposing BV-2 cells to 10 min of oxygen-glucose deprivation (OGD). In vivo, IPC was performed by a transient cerebral ischemia of 10 min occlusion of the middle cerebral artery (MCA) in mice. We found that the NLRP3 inflammasome was activated and cell pyroptosis was induced at 6 h and 24 h post-stroke in an ischemic brain. IPC treatment increased cell viability under OGD state, reduced the infarct size, and attenuated the neurological deficits of mice. However, the effects NLRP3 inflammasome activation and pyroptosis after stroke were attenuated by IPC, which decreased the expression of NLRP3, ASC, cleaved caspase 1, and GSDMD-N and reduced the production of IL-1β and IL-18. In addition, confocal immunofluorescence staining of Annexin V-mCherry and SYTOX green was inhibited by IPC. These findings suggest a more enhanced link between IPC and inflammatory signature and cell death, highlighting that the NLRP3 inflammasome may act as a promising target for the prevention and treatment of ischemic stroke.

Fine particulate matter exposure aggravates ischemic injury via NLRP3 inflammasome activation and pyroptosis

Aims

Accumulating evidence has suggested that airborne fine particulate matter (PM2.5) exposure is associated with an increased risk of ischemic stroke. However, the underlying mechanisms have not been fully elucidated. In this study, we aim to investigate the role and mechanisms of NLRP3 inflammasome and pyroptosis in ischemic stroke after PM2.5 exposure.

Methods

The BV‐2 and HMC‐3 microglial cell lines were established and subjected to oxygen–glucose deprivation and reoxygenation (OGD/R) with or without PM2.5 exposure. We used the CCK‐8 assay to explore the effects of PM2.5 on cell viability of BV‐2 and HMC‐3 cells. Then, the effects of PM2.5 exposure on NLRP3 inflammasome and pyroptosis following OGD/R were detected by western blotting, ELISA, and the confocal immunofluorescence staining. Afterwards, NLRP3 was knocked down to further validate the effects of PM2.5 on cell viability, NLRP3 inflammasome activation, and pyroptosis after OGD/R in HMC‐3 cells. Finally, the intracellular reactive oxygen species (ROS) was measured and the ROS inhibitor N‐acetyl‐L‐cysteine (NAC) was used to investigate whether ROS was required for PM2.5‐induced NLRP3 inflammasome activation and pyroptosis under ischemic conditions.

Results

We found that PM2.5 exposure decreased the viability of BV‐2 and HMC‐3 cells in a dose‐ and time‐dependent manner under ischemic conditions. Furthermore, PM2.5 exposure aggravated NLRP3 inflammasome activation and pyroptosis after OGD/R, as indicated by an increased expression of NLRP3, ASC, pro‐caspase‐1, Caspase‐1, GSDMD, and GSDMD‐N; increased production of IL‐1β and IL‐18; and enhanced Caspase‐1 activity and SYTOX green uptake. However, shRNA NLRP3 treatment attenuated the effects of PM2.5 on cell viability, NLRP3 inflammasome activation, and pyroptosis. Moreover, we observed that PM2.5 exposure increased the production of intracellular ROS following OGD/R, while inhibiting ROS production with NAC partially attenuated PM2.5‐induced NLRP3 inflammasome activation and pyroptosis under ischemic conditions.

Conclusion

These results suggested that PM2.5 exposure triggered the activation of NLRP3 inflammasome and pyroptosis under ischemic conditions, which may be mediated by increased ROS production after ischemic stroke. These findings may provide a more enhanced understanding of the interplay between PM2.5 and neuroinflammation and cell death, and reveal a novel mechanism of PM2.5‐mediated toxic effects after ischemic stroke.

Genetic contribution and functional impairment of inflammasome in sickle cell disease

BACKGROUND

Sickle cell disease (SCD), one of the most common single-gene disorders, is caused by mutations in the hemoglobin ß-chain gene. Clinical presentation is heterogeneous, and inflammation is a common condition. Thereby, we hypothesized that inflammasome and related cytokine IL-1ß could represent significant SCD pathogenesis contributors.

MATERIAL AND METHODS

161 SCD (SS/Sβ) patients were enrolled for the study. Seven single nucleotide polymorphisms (SNPs) in 5 inflammasome genes (NLRP1, NLRP3, NLRC4, CARD8, IL1B) were selected based on minor allele frequency. Total peripheral blood mononuclear cells (PBMC) and monocytes were isolated from 10 out of 161 SCD patients (HbSS) and 10 healthy donors (control group, Ctrl) for inflammasome analysis.

RESULTS

SCD patients presented a functional impairment of inflammasome, with monocytes and peripheral blood mononuclear cells (PBMC) exhibiting a different NLRP3 inflammasome activation rate. Gain-of-function variants in NLRP1 and IL1B genes resulted associated with a mild SCD clinical presentation.

DISCUSSION

Our results can contribute to the understanding of SCD inflammation. SCD patients showed possible exhaustion of monocytes due to chronic inflammation, moreover others cells in PBMC can contribute to the NLRP3 inflammasome activation. NLRP1 gain-of-function was associated with mild clinical presentation, suggesting that other inflammasome receptors can be involved in SCD. This is the first study reporting a significant contribution of inflammasome SNPs in SCD.

Genetic Polymorphisms of FCRL3, NLRP3 and IL2 are Associated with the Risk of Head and Neck Cancer in a Chinese Population

Purpose

This study aimed to evaluate the associations between immune-related gene (FCRL3, NLRP3 and IL2) polymorphisms and the risk of head and neck cancer (HNC).

Methods

Six polymorphisms of FCRL3, NLRP3 and IL2 were genotyped in 400 HNC cases and 400 controls using a MassARRAY platform.

Results

rs11264799-T was a protective variant against HNC risk, while rs7528684-G, rs35829419-A and rs6822844-T were all risk alleles for HNC (p < 0.05). rs11264799-TT was correlated with reduced HNC risk, while rs7528684-GG and rs6822844-TG were associated with an elevated risk of disease (p < 0.05). Moreover, rs11264799 was correlated with a declining risk of HNC in three genetic models (p < 0.05). In contrast, rs7528684 exhibited an elevated risk of HNC in recessive and additive models; rs35829419 and rs6822844 were associated with an increased risk of disease in dominant and additive models (p < 0.05). Finally, an interaction was observed between the above SNPs and drinking (p < 0.05).

Conclusion

The results expand our knowledge on immune-related gene polymorphisms in HNC and provide clues for further functional study on the pathogenesis of HNC.

A gain-of-function NLRP3 3'-UTR polymorphism causes miR-146a-mediated suppression of NLRP3 expression and confers protection against sepsis progression

Nucleotide-binding domain and leucine-rich repeat (LRR)-containing family protein 3 (NLRP3) regulated the maturation of inflammation-related cytokines by forming NLRP3 inflammasome, which plays pivotal roles in sepsis pathogenesis. In this study, we evaluated the genetic association of NLRP3 polymorphisms with sepsis (640 patients and 769 controls) and characterized the impact of NLRP3 polymorphisms on NLRP3 expression and inflammatory responses. No significant differences were observed in genotype/allelic frequencies of NLRP3 29940G>C between sepsis cases and controls. The G allele was significantly overrepresented in patients with septic shock than those in sepsis subgroup, and the GC/GG genetypes were related to the 28-day mortality of sepsis. Lipopolysaccharide challenge to peripheral blood mononuclear cells showed a significant suppression of NLRP3 mRNA expression and release of IL-1β and TNF-α in CC compared with the GC/GG genotype category. Functional experiments with luciferase reporter vectors containing the NLRP3 3′-UTR with the 29940 G-to-C variation in HUVECs and THP-1 cells showed a potential suppressive effect of miR-146a on NLRP3 transcription in the presence of the C allele. Taken together, these results demonstrated that the 29940 G-to-C mutation within the NLRP3 3′-UTR was a gain-of-function alteration that caused the suppression of NLRP3 expression and downstream inflammatory cytokine production via binding with miR-146a, which ultimately protected patients against susceptibility to sepsis progression and poor clinical outcome.

Migraine and neuroinflammation: the inflammasome perspective

BACKGROUND

Neuroinflammation has an important role in the pathophysiology of migraine, which is a complex neuro-glio-vascular disorder. The main aim of this review is to highlight findings of cortical spreading depolarization (CSD)-induced neuroinflammatory signaling in brain parenchyma from the inflammasome perspective. In addition, we discuss the limited data of the contribution of inflammasomes to other aspects of migraine pathophysiology, foremost the activation of the trigeminovascular system and thereby the generation of migraine pain.

MAIN BODY

Inflammasomes are signaling multiprotein complexes and key components of the innate immune system. Their activation causes the production of inflammatory cytokines that can stimulate trigeminal neurons and are thus relevant to the generation of migraine pain. The contribution of inflammasome activation to pain signaling has attracted considerable attention in recent years. Nucleotide-binding domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) is the best characterized inflammasome and there is emerging evidence of its role in a variety of inflammatory pain conditions, including migraine. In this review, we discuss, from an inflammasome point of view, cortical spreading depolarization (CSD)-induced neuroinflammatory signaling in brain parenchyma, the connection with genetic factors that make the brain vulnerable to CSD, and the relation of the inflammasome with diseases that are co-morbid with migraine, including stroke, epilepsy, and the possible links with COVID-19 infection.

CONCLUSION

Neuroinflammatory pathways, specifically those involving inflammasome proteins, seem promising candidates as treatment targets, and perhaps even biomarkers, in migraine.

Vascular Risk Factors and Alzheimer's Disease: Blood-Brain Barrier Disruption, Metabolic Syndromes, and Molecular Links

Alzheimer's disease (AD) is a neurodegenerative disorder, marked by cortical and hippocampal deposition of amyloid-β (Aβ) plaques and neurofibrillary tangles and cognitive impairment. Studies indicate a prominent link between cerebrovascular abnormalities and the onset and progression of AD, where blood-brain barrier (BBB) dysfunction and metabolic disorders play key risk factors. Pericyte degeneration, endothelial cell damage, astrocyte depolarization, diminished tight junction integrity, and basement membrane disarray trigger BBB damage. Subsequently, the altered expression of low-density lipoprotein receptor-related protein 1 and receptor for advanced glycation end products at the microvascular endothelial cells dysregulate Aβ transport across the BBB. White matter lesions and microhemorrhages, dyslipidemia, altered brain insulin signaling, and insulin resistance contribute to tau and Aβ pathogenesis, and oxidative stress, mitochondrial damage, inflammation, and hypoperfusion serve as mechanistic links between pathophysiological features of AD and ischemia. Deregulated calcium homeostasis, voltage gated calcium channel functioning, and protein kinase C signaling are also common mechanisms for both AD pathogenesis and cerebrovascular abnormalities. Additionally, APOE polymorphic alleles that characterize impaired cerebrovascular integrity function as primary genetic determinants of AD. Overall, the current review enlightens key vascular risk factors for AD and underscores pathophysiologic relationship between AD and vascular dysfunction.

Inflammaging and neurodegenerative diseases: Role of NLRP3 inflammasome activation in brain atherosclerotic vascular disease

The activation of the NLRP3 inflammasome-IL-1β pathway has been clearly shown to be involved in the pathophysiology of cardiovascular diseases, but its role in cerebral atherosclerotic vascular disease has not been fully clarified. Here we provide an overview on the current knowledge about the relevance of the activation of this mechanism in the onset of acute brain atherosclerotic vascular disease and the subsequent tissue damage. Some variants of NLRP3-related genes seem to reduce the susceptibility to acute ischaemic stroke in selected cohorts, although no clear evidence exists either supporting or excluding any role of this pathway in its pathophysiology. Interestingly, robust experimental and clinical data support a major role of the activation of the NLRP3 inflammasome-IL-1β pathway in the post-event inflammatory cascade which leads to neurodegeneration. This evidence highlights a potential dual role of these molecules in brain pre- and post-ischaemic events, supporting the need for further studies, including clinical trials evaluating the modulation of this pathway for stroke prevention and post-stroke treatment.

Investigating the possible association between NLRP3 gene polymorphisms and myasthenia gravis

INTRODUCTION

In this case-control study, we investigated the association between nucleotide oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) single-nucleotide polymorphisms (SNPs) rs10754558, rs3806265, rs4612666, and rs35829419 and myasthenia gravis (MG).

METHODS

Samples from MG patients were selected from a previous study conducted in our neuromuscular clinic, which investigated the association between human leukocyte antigen (HLA) class II genes and MG. Genetic data of controls were also available from another study. The NLRP3 SNPs genotyping was performed using the TaqMan method.

RESULTS

A total of 93 blood samples from eligible Iranian patients with MG and 56 samples from healthy controls were obtained. The NLRP3 rs3806265 "C" allele was significantly more frequent in MG patients (P < .001; odd ratio [OR] = 2.33, 95% confidence interval [CI]: 1.4-4.0) than controls. The "CC" genotype of this SNP was found in 18.27% of patients, but none of the controls (P < .001). The distribution of other SNPs was similar between the groups.

DISCUSSION

These preliminary results suggest that there might be some associations between the NLRP3 gene polymorphism and MG.

RalA exerts an inhibitory effect on IL-1β/IL-18 secretion by blocking NLRP3 inflammasome activation in levornidazole-treated human THP-1 macrophages

The NLRP3 inflammasome is an important mediator of inflammatory responses and its regulation is an active area of research. RalA is a Ras-like GTPase, which play pivotal roles in the biology of cells. So far, there have been very few studies on RalA regulating inflammatory responses. Bioinformatics analysis predicted that RalA might participate in the regulatory network of NLRP3 inflammasome, which has been confirmed in THP-1 macrophages. After virtual screening of compounds, it was found that levonidazole selected from our virtual small molecule compound library has the potential to bind to RalA. Of note, the interaction of RalA/levornidazole was verified by Surface Plasmon Resonance-Biacore T200, LC/MS analysis and Western blotting analysis. Molecular dynamics simulations revealed that the conformational changes of RalA might be regulated by levornidazole. Additionally, IL-1β/IL-18 secretion from ATP + LPS stimulated THP-1-derived macrophages was RalA-dependently suppressed by levornidazole, suggesting that RalA might have an inhibitory effect on NLRP3 inflammasome activation. The results of co-immunoprecipitation and RalA depletion experiments showed that levornidazole could induce RalA to block the assembly of NLRP3/ASC/pro-caspase-1 complex, thereby reducing the levels of cleaved-caspase-1 and IL-1β/IL-18 secretion. Our study has suggested an anti-inflammatory function of RalA and identified its targeting chemical compound. Overall, this study clarifies a novel pharmacological mechanism by which RalA/levornidazole inhibits NLRP3 inflammasome activation and IL-1β/IL-18 secretion.

A Common NLRC4 Gene Variant Associates With Inflammation and Pulmonary Function in Human Immunodeficiency Virus and Tuberculosis

BACKGROUND

Inflammasomes mediate inflammation in adults living with both human immunodeficiency virus (HIV) and tuberculosis (TB), but the relevance of inflammasome gene polymorphisms in TB-associated pulmonary damage is unknown. We hypothesized that functional single-nucleotide polymorphisms (SNPs) in inflammasome pathway genes modify systemic and pulmonary inflammation, contributing to respiratory impairment in adults living with HIV/pulmonary TB.

METHODS

This was a prospective cohort study set in South Africa following individuals living with HIV/TB up to 48 weeks post-antiretroviral therapy (ART) initiation. Ten functional SNPs in 5 inflammasome pathway genes were related to circulating inflammatory biomarkers and lung function assessed by spirometry pre- and post-ART initiation. Analyses used 2-sided t tests, Wilcoxon rank sum tests, Spearman correlation coefficients, linear regression, and generalized estimating equation models.

RESULTS

Among 102 patients with baseline samples, the minor allele (T) in NLRC4 rs385076 was independently associated with lower levels of interleukin (IL)-18 and IL-6 before and up to 12 weeks post-ART initiation (Benjamini-Hochberg corrected P values < .02). Patients with the CT/TT genotypes also had improved lung function vs CC patients up to 48 weeks post-ART initiation (forced vital capacity, 206 mL higher; 95% confidence interval [CI], 67-345 mL; P = .004 and forced expiratory volume in 1 second, 143 mL higher; 95% CI, 11-274 mL; P = .034).

CONCLUSIONS

A common SNP in the NLRC4 inflammasome may modify TB-associated inflammation in clinically relevant ways. This SNP may identify high-risk groups for lung damage in TB. Inhibition of NLRC4 activity may be an important approach for TB host-directed therapy.

Inhibition of NLRP3 Inflammasome: A Prospective Target for the Treatment of Ischemic Stroke

Stroke is one of the major devastating diseases with no effective medical therapeutics. Because of the high rate of disability and mortality among stroke patients, new treatments are urgently required to decrease brain damage following a stroke. In recent years, the inflammasome is a novel breakthrough point that plays an important role in the stroke, and the inhibition of inflammasome may be an effective method for stroke treatment. Briefly, inflammasome is a multi-protein complex that causes activation of caspase-1 and subsequent production of pro-inflammatory factors including interleukin (IL)-18 and IL-1β. Among them, the NLRP3 inflammasome is the most typical inflammasome, which can detect cell damage and mediate inflammatory response to tissue damage in ischemic stroke. The NLRP3 inflammasome has become a key mediator of post-ischemic inflammation, leading to a cascade of inflammatory reactions and cell death eventually. Thus, NLRP3 inflammasome is an ideal therapeutic target due to its important role in the inflammatory response after ischemic stroke. In this mini review article, we will summarize the structure, assembly, and regulation of NLRP3 inflammasome, the role of NLRP3 inflammasome in ischemic stroke, and several treatments targeting NLRP3 inflammasome in ischemic stroke. The further understanding of the mechanism of NLRP3 inflammasome in patients with ischemic stroke will provide novel targets for the treatment of cerebral ischemic stroke patients.

Genetic susceptibility to cerebrovascular disease: A systematic review

Investigation of genetic susceptibility to cerebrovascular disease has been of growing interest. A systematic review of human studies assessing neurogenomic aspects of cerebrovascular disease was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. Any association study exploring genetic variants located in the exome associated with one of the major cerebrovascular diseases with at least 500 subjects was eligible for inclusion. Of 6874 manuscripts identified, 35 studies met the inclusion criteria. Most studies of interest focused on ischemic stroke and cerebrovascular occlusive disease. Large cohort genetic association studies on hemorrhagic cerebrovascular disease were less common. In addition to rare, well-established monogenic conditions with significant risk for cerebrovascular disease, a number of genetic variants are also relevant to cerebrovascular pathogenesis as part of a multifactorial process. The 45 polymorphisms identified were located in genes involved in processes related to endothelial and vascular health (15 (33.4%) variants), plasma lipid metabolism (10 (22.2%) variants), inflammation (9 (20%) variants), coagulation (3 (6.7%) variants), and blood pressure modulation (2 (4.4%) variants), and other (6 (13.3%) variants). This work represents a comprehensive overview of genetic variants in the exome relevant to ischemic and hemorrhagic stroke pathophysiology.

Lipoprotein lipase gene polymorphisms as risk factors for stroke: a computational and meta-analysis

OBJECTIVES

Stroke is the most common neurological disorder and genetic susceptibility has an important role in its etiology. Polymorphism in several genes such as lipoprotein lipase (LPL) is propounded as a risk for stroke. This meta-analysis investigated the association of rs285 and rs320 LPL polymorphism with stroke risk.

MATERIALS AND METHODS

We searched PubMed, Clarivate Analytics Web of Science, Google Scholar, and Science Direct databases for appropriate studies. The odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate the strength of this association. Also, the effects of four common polymorphisms (rs268, rs285, rs320, and rs328) on the molecular aspects of LPL were evaluated by in silico tools. Five studies were included in meta-analysis after screening.

RESULTS

Our data indicated that rs320 significantly decreased the risk of stroke (G vs. T: OR= 0.64, 95%CI=0.54-0.76; GG vs. TT: OR=0.47, 95%CI=0.29-0.75; TG vs. TT: OR=0.65, 95%CI=0.53-0.80; TG+GG vs. TT: OR=0.62, 95%CI=0.51-0.75; GG vs. TT+TG: OR=0.51, 95%CI=0.32-0.82). Moreover, a significant association between rs285 and diminution of stroke risk was seen (P- vs. P+: OR=0.72, 95%CI=0.58-0.91; P-P- vs. P+P+: OR=0.50, 95%CI=0.31-0.82; P+P-+P-P- vs. P+P+: OR=0.72, 95%CI=0.53-0.96; P-P- vs. P+P++P+P-: OR=0.581, 95%CI=0.369-0.916). Also, the same results were observed after stratifying, without any publication bias (PEgger>0.05). Furthermore, computational analysis revealed that rs268 and rs328 may affect the protein structure (prediction: non-neutral; score=19; expected accuracy=59%) while rs320 could affect the RNA structure (distance=0.2264, P-value=0.0534; P<0.2 is significant).

CONCLUSION

This meta-analysis indicated that risk of stroke was decreased in rs320 and rs285 polymorphisms in the LPL gene.

Rs4612666 Polymorphism of the NLRP3 Gene Is Associated with the Occurrence of Large Artery Atherosclerotic Ischemic Strokes and Microembolic Signals

Purpose

Large artery atherosclerosis (LAA) ischemic stroke (IS) is the most common IS subtype, and microemboli are clinically important for indicating an increased risk of IS. Nucleotide-binding domain-like receptor protein 3 (NLRP3) plays a crucial role in the pathogenesis of atherosclerosis. The aim of this study is to investigate the relationship between NLRP3 gene polymorphisms and susceptibility for LAA IS and microembolic signals (MES) in the Chinese Han population.

Methods

We studied 293 patients diagnosed with LAA IS and 265 controls. Transcranial Doppler (TCD) was used to monitor the MES in all of the patients. Depending on the presence or absence of MES, the patients were divided into MES-positive and MES-negative subgroups. PCR-RFLP or direct sequencing were used to analyze three NLRP3 gene polymorphisms.

Results

Seventy-six patients presented with MES and the MES-positive rate was 25.94%. Logistic regression analysis showed that the TT genotype frequency for the rs4612666 gene polymorphism was higher in study patients than in the controls (adjusted P = 0.001) and higher in MES-positive patients compared to MES-negative patients (adjusted P = 0.015). The T allele of rs4612666 was associated with an increased risk for developing LAA IS and MES (P = 0.001; P = 0.015, resp.). Prevalence of the CCC haplotype was higher in the controls than in the patients (P = 0.009) and prevalence of the TGT haplotype was lower in the controls than in the patients (P = 0.019).

Conclusions

The NLRP3 rs4612666 gene polymorphism may be related to the occurrence of LAA IS and MES, suggesting that the NLRP3 gene polymorphism increases the susceptibility of LAA IS by changing the plaque vulnerability.

The NLRP3 and CASP1 gene polymorphisms are associated with developing of acute coronary syndrome: a case-control study

The protein products of NLRP3 and CASP1 genes are involved in the cleavage of pro-IL-1B and pro-IL-18 leading to the active cytokines, which play an important role in the development of the acute coronary syndrome (ACS). The aim of the present study was to evaluate whether NLRP3 and CASP1 gene polymorphisms are biomarkers of ACS susceptibility in Mexican population. Two polymorphisms of the CASP1 gene [G+7/in6A (rs501192) and A10370-G Exon-6 (rs580253)] and one of the NLRP3 gene [UTR'3 G37562-C (rs10754558)] were genotyped by 5' exonuclease TaqMan assays in a group of 617 patients with ACS and 609 control individuals. Under recessive model, the CASP1 G+7/in6A polymorphism was associated with an increased risk of developing ACS when compared to healthy controls (OR = 1.76, 95% CI 1.08-2.86, P _Res  = 0.022). In the same way, under recessive model, the CASP1 A10370-G was associated with increased risk of ACS (OR = 1.75, 95% CI 1.07-2.85, P _Res  = 0.025). Moreover, under co-dominant, dominant, over-dominant, and additive models, the NLRP3 UTR'3 G37562-C was associated with a decreased risk of ACS (OR = 0.45, 95%CI 0.22-0.92, P _Co-dom  = 0.006; OR = 0.61, 95%CI 0.44-0.84, P _Dom  = 0.002; OR = 0.67, 95%CI 0.48-0.94, P _Over-dom  = 0.02; and OR = 0.65, 95%CI 0.50-0.94, P _Add  = 0.02, respectively). In summary, this study demonstrates that the G+7/in6A and A10370-G polymorphisms of the CASP1 gene are associated with increased risk of developing ACS, whereas the UTR'3 G37562-C polymorphism of the NLRP3 gene is associated with a decreased risk of developing ACS in Mexican population.

Common Variation in NLRP3 Is Associated With Early Death and Elevated Inflammasome Biomarkers Among Advanced HIV/TB Co-infected Patients in Botswana

Background

Elevated inflammation is associated with early mortality among HIV/tuberculosis (TB) patients starting antiretroviral therapy (ART); however, the sources of immune activation are unclear. We hypothesized that common variation in innate immune genes contributes to excessive inflammation linked to death. As single nucleotide polymorphisms (SNPs) in inflammasome pathway genes can increase risk for inflammatory diseases, we investigated their association with early mortality among a previously described cohort of HIV/TB patients initiating ART in Botswana.

Methods

We genotyped 8 SNPs within 5 inflammasome pathway genes and determined their association with death. For adjusted analyses, we used a logistic regression model. For SNPs associated with mortality, we explored their relationship with levels of systemic inflammatory markers using a linear regression model.

Results

Ninety-four patients in the parent study had samples for genetic analysis. Of these, 82 (87%) were survivors and 12 (13%) died within 6 months of starting ART. In a logistic regression model, NLRP3 rs10754558 was independently associated with a 4.1-fold increased odds of death (95% confidence interval, 1.04–16.5). In adjusted linear regression models, the NLRP3 rs10754558-G allele was linked to elevated IL-18 at baseline (Beta, 0.23; SE, 0.10; P = .033) and week 4 post-ART (Beta, 0.24; SE, 0.11; P = .026). This allele was associated with increased MCP-1 at baseline (Beta, 0.24; SE, 0.10; P = .02) and IL-10 (Beta, 0.27; SE, 0.11; P = .013) at week 4 post-ART.

Conclusion

The NLRP3 rs10754558-G SNP is associated with an increased risk for early mortality in HIV/TB patients initiating ART. These patients may benefit from therapies that decrease inflammasome-mediated inflammation.

Inflammasome biology, molecular pathology and therapeutic implications

Inflammasomes are intracellular multiprotein signaling complexes, mainly present in myeloid cells. They commonly assemble around a cytoplasmic receptor of the nucleotide-binding leucine-rich repeat containing receptor (NLR) family, although other cytoplasmic receptors like pyrin have been shown to form inflammasomes. The nucleation of the multiprotein scaffolding platform occurs upon detection of a microbial, a danger or a homeostasis pattern by the receptor that will, most commonly, associate with the adaptor protein ASC (apoptosis-associated speck-like protein containing a CARD) through homotypic domain interactions resulting in recruitment of procaspase-1. This will lead to the autoproteolytic activation of caspase-1, which regulates the secretion of proinflammatory IL1β and IL18 cytokines and pyroptosis, a caspase-1-mediated form of cell death. Pyroptosis occurs through cleavage of Gasdermin D, a membrane pore forming protein. Recently, non-canonical inflammasomes have been described, which directly sense intracellular pathogens through caspase-4 and -5 in humans, leading to pyroptosis. Inflammasomes are important in host defense; however, a deregulated activity is associated with a number of inflammatory, immune and metabolic disorders. Furthermore, mutations in inflammasome receptor coding genes are causal for an increasing number of rare autoinflammatory diseases. Biotherapies targeting the products of inflammasome activation as well as molecules that directly or indirectly inhibit inflammasome nucleation and activation are promising therapeutic areas. This review discusses recent advances in inflammasome biology, the molecular pathology of several inflammasomes, and current therapeutic approaches in autoinflammatory diseases and in selected common multifactorial inflammasome-mediated disorders.

Genetics of Inflammasomes

Mutations in inflammasome genes are responsible for rare monogenic and polygenic autoinflammatory diseases. On the other side, genetic polymorphisms in the same molecules contribute to the development of common multifactorial diseases (i.e., autoimmune diseases, cardiovascular pathologies, cancer). In this chapter we depicted the current knowledge about inflammasome genetics.

Cordycepin confers neuroprotection in mice models of intracerebral hemorrhage via suppressing NLRP3 inflammasome activation

Neuroinflammation has been recognized as a major contributor to brain injury caused by intracerebral hemorrhage (ICH). Nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome acts as an important mediator of inflammatory response in various inflammation-related diseases including hemorrhagic insults. Cordycepin has recently been shown to possess anti-inflammatory effect; however, its role and the possible underlying mechanisms in ICH remain unclear. This study was designed to investigate the neuroprotective effect of cordycepin in mice models of ICH and to elucidate the underlying molecular mechanisms. ICH was induced in male ICR mice by injecting autologous blood infusion stereotactically. Cordycepin was then given intraperitoneally (i.p.) at 30 min after ICH induction. The results demonstrated that NLRP3 inflammasome was activated and exacerbated the inflammatory progression after ICH. Cordycepin treatment significantly alleviated neurological deficits, brain edema, and perihematomal tissue damage following ICH. These changes were accompanied by downregulated NLRP3 inflammasome components expression and a reduction of production and release of inflammasome substrates interleukin-1beta (IL-1β) and interleukin-18 (IL-18). Furthermore, cordycepin ameliorated neuronal death in the perihematomal regions, accompanied by a large reduction in the expression of high-mobility group protein B 1 (HMGB1) post-ICH. In conclusion, this study provides in vivo evidence that cordycepin confers neuroprotective effect in the models of ICH, possibly through the suppression of NLRP3 inflammasome activation.

Are the innate and adaptive immune systems setting hypertension on fire?

Hypertension is the most common chronic cardiovascular disease and is associated with several pathological states, being an important cause of morbidity and mortality around the world. Low-grade inflammation plays a key role in hypertension and the innate and adaptive immune systems seem to contribute to hypertension development and maintenance. Hypertension is associated with vascular inflammation, increased vascular cytokines levels and infiltration of immune cells in the vasculature, kidneys and heart. However, the mechanisms that trigger inflammation and immune system activation in hypertension are completely unknown. Cells from the innate immune system express pattern recognition receptors (PRR), which detect conserved pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) that induce innate effector mechanisms to produce endogenous signals, such as inflammatory cytokines and chemokines, to alert the host about danger. Additionally, antigen-presenting cells (APC) act as sentinels that are activated by PAMPs and DAMPs to sense the presence of the antigen/neoantigen, which ensues the adaptive immune system activation. In this context, different lymphocyte types are activated and contribute to inflammation and end-organ damage in hypertension. This review will focus on experimental and clinical evidence demonstrating the contribution of the innate and adaptive immune systems to the development of hypertension.

Association of Matrix Metalloproteinase-1 and Matrix Metalloproteinase-3 Gene Variants with Ischemic Stroke and Its Subtype

BACKGROUND

Genetic variations in the genes of matrix metalloproteinases (MMPs) may play an important role in the pathogenesis of ischemic stroke (IS). Here we investigate the association between MMP-1 -1607 1G/2G and MMP-3 -1171 5A/6A genetic polymorphisms and etiological subtypes of IS in the Han Chinese population.

METHODS

A total of 640 eligible patients with IS and 637 age- and gender-matched apparently healthy volunteers were enrolled. Subtypes of IS were classified by Trial of Org 10172 in Acute Stroke Treatment criteria. MMP-1 (-1607 1G/2G) and MMP-3 (-1171 5A/6A) polymorphisms were evaluated using polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

The frequencies of the 5A/6A + 5A/5A genotypes and 5A allele were significantly higher in patients with IS than in controls (P <.001, P <.001, respectively). No association was found between MMP-1 1G/2G polymorphism and overall IS. In subgroup analyses, MMP-1 1G/2G and 2G/2G genotypes increased the risk of small-artery occlusion (SAO) subtype (multivariate-adjusted, P <.001, P = .002, respectively), and MMP-3 5A/6A + 5A/5A genotypes were related with large-artery atherosclerosis (LAA) subtype (multivariate-adjusted, P <.001). Haplotype analyses indicated that 2G-6A and 1G-5A increased the risk of SAO (multivariate-adjusted, P = .029) and LAA (multivariate-adjusted, P <.001), respectively.

CONCLUSIONS

MMP-1 (-1607 1G/2G) and MMP-3 (-1171 5A/6A) polymorphisms may contribute to different subtypes of IS susceptibility.

Inflammasomes link vascular disease with neuroinflammation and brain disorders

The role of inflammation in neurological disorders is increasingly recognised. Inflammatory processes are associated with the aetiology and clinical progression of migraine, psychiatric conditions, epilepsy, cerebrovascular diseases, dementia and neurodegeneration, such as seen in Alzheimer's or Parkinson's disease. Both central and systemic inflammatory actions have been linked with the development of brain diseases, suggesting that complex neuro-immune interactions could contribute to pathological changes in the brain across multiple temporal and spatial scales. However, the mechanisms through which inflammation impacts on neurological disease are improperly defined. To develop effective therapeutic approaches, it is imperative to understand how detrimental inflammatory processes could be blocked selectively, or controlled for prolonged periods, without compromising essential immune defence mechanisms. Increasing evidence indicates that common risk factors for brain disorders, such as atherosclerosis, diabetes, hypertension, obesity or infection involve the activation of NLRP3, NLRP1, NLRC4 or AIM2 inflammasomes, which are also associated with various neurological diseases. This review focuses on the mechanisms whereby inflammasomes, which integrate diverse inflammatory signals in response to pathogen-driven stimuli, tissue injury or metabolic alterations in multiple cell types and different organs of the body, could functionally link vascular- and neurological diseases and hence represent a promising therapeutic target.