Increased IL18 mRNA levels in peripheral artery disease and its association with triglyceride and LDL cholesterol levels: a pilot study

A Systematic Review of Interleukins as Diagnostic and Prognostic Biomarkers for Peripheral Artery Disease

Background: Peripheral artery disease (PAD) involves atherosclerosis of the lower extremity arteries and is a major contributor to limb loss and death worldwide. Several studies have demonstrated that interleukins (ILs) play an important role in the development and progression of PAD; however, a comprehensive literature review has not been performed. Methods: A systematic review was conducted and reported according to PRISMA guidelines. MEDLINE was searched from inception to 5 December 2022, and all studies assessing the association between ILs and PAD were included. Results: We included 17 studies from a pool of 771 unique articles. Five pro-inflammatory ILs (IL-1β, IL-2, IL-5, IL-6, and IL-8) and one pro-atherogenic IL (IL-12) were positively correlated with PAD diagnosis and progression. In contrast, two anti-inflammatory ILs (IL-4 and IL-10) were protective against PAD diagnosis and adverse limb events. Specifically, IL-6 and IL-8 were the most strongly associated with PAD and can act as potential disease biomarkers to support the identification and treatment of PAD. Conclusions: Ongoing work to identify and validate diagnostic/prognostic inflammatory biomarkers for PAD has the potential to assist clinicians in identifying high-risk patients for further evaluation and management which could reduce the risk of adverse cardiovascular and limb events.

Serum il-18 and rs187238 single nucleotide polymorphism are associated with high-density lipoprotein changes in covid-19 outpatients

AIM

COVID-19 is an inflammatory disease and its prognosis is associated with cardiovascular risk, which can be associated with changes in lipoprotein metabolism. The single nucleotide polymorphism (SNP) rs187238 of Interleukin (IL)-18 is extensively reported in association with worsening inflammatory and cardiovascular disease (CVD). This study evaluated the association of IL-18 levels and its SNP rs187238 with lipoprotein profile changes in COVID-19 outpatients.

METHODS

Observational, analytical, cross-sectional study that evaluated 250 patients with respiratory syndrome, 36% (n = 90) with COVID-19. Serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), triglycerides (TG), apolipoproteins A-I and B (Apo A-I and Apo B) and IL-18 levels were determined. Polymorphism genotyping was done by real-time polymerase chain reaction (qPCR). The significance level was p < 0.05.

RESULTS

Patients with COVID-19 showed a reduction in TC and HDL-c, without difference in IL-18. HDL-c and LDL-c had a high frequency outside the reference values. There was a negative correlation of IL-18 with HDL-c and a positive correlation with Apo B/Apo A-I ratio. The frequencies of the C (wild) and G (polymorphic) alleles between patients with and without COVID-19 followed the Hardy-Weinberg equilibrium. However, COVID-19 was associated with reduced HDL-c and Apo A-I values in patients with the CC genotype.

CONCLUSION

IL-18 levels and its SNP rs187238 were associated with decreased HDL-c and Apo A-I in COVID-19 outpatients.

No association between interleukin-18 levels and risk of cardiovascular disease: A Mendelian randomization study

OBJECTIVE

In this study, Mendelian randomization method was used to determine whether there was a causal association between inflammatory cytokine IL-18 and cardiovascular disease risk.

METHODS

We performed a meta-analysis to evaluate the association between IL-18-137G/C and -607C/A polymorphisms and phenotype of IL-18 levels, and also the risks of CVD. All the literatures were searched before September 30, 2019. The logistic regression and linear regression were used to evaluate between IL-18 level and the risk of CVDs.

RESULT

Twelve eligible articles of the association between IL-18-137G/C and CVD risks and 8 eligible literatures related to IL-18-607C/A and CVD risks; 2 qualified literatures of the association between IL-18 SNPs and IL-18 levels and 4 eligible literatures related to IL-18 levels and CVD risks. Data of 4 literatures on the correlation between IL-18 level and CVD were summarized. Compared with patients with CVD, the mean of IL-18 level in the normal group was significantly decreased by 50.844 pg/ml (P < 0.05). But the association between IL-18-137G/C, IL-18-607C/A and CVD were not significant (P > 0.05), and the association between IL-18-607C/A and IL-18 level was also not significant (P > 0.05), Mendelian randomization study was failed to prove the association between IL-18 level and CVD risk.

CONCLUSION

This study does not support a causal association between IL-18 level and the risks of CVD.

AGT rs699 and AGTR1 rs5186 gene variants are associated with cardiovascular-related phenotypes in atherosclerotic peripheral arterial obstructive disease

BACKGROUND

Peripheral arterial diseases (PAD) refer to the arterial diseases other than coronary arteries and the aorta. Atherosclerosis is the major cause of PAD. Renin angiotensin aldosterone system (RAAS)-related genes were associated with cardiovascular diseases. Angiotensin II is the pro-inflammatory, proliferative and vasoconstrictor effector of RAAS in the vascular system.

AIMS

In this study, we aimed to investigate whether the effects of the angiotensinogen (AGT) rs699 (M268T), angiotensin-converting enzyme (ACE) I/D (rs1799752), angiotensin II receptor type 1 (AGTR1) (A1166C) rs5186, and angiotensin II receptor type 2 (AGTR2) rs35474657 variants were associated with PAD etiology due to atherosclerotic involvement of aorta-iliac and femoro-popliteal artery occlusions.

METHODS

AGT rs699, AGTR1 rs5186, ACE I/D (rs1799752), AGTR2 rs35474657 gene variants were determined by real-time polymerase chain reaction (RT-PCR) in 63 PAD patients (33 femoro-popliteal, 30 aorta-iliac) and 70 healthy controls.

RESULTS

Although there was no significant relationship in the genotype frequencies of AGT rs699, AGTR1 rs5186, ACE I/D (rs1799752), and AGTR2 rs35474657 variants between PAD and control groups (p > 0.05), AGT rs699 TT genotype was significantly associated with fasting glucose (p = 0.023) in PAD patients. Besides, CC genotype of rs699 was significantly related with HDL-cholesterol levels (p = 0.020) in PAD group. Furthermore, AGTR1 rs5186 CC genotype carriers demonstrated significantly higher LDL-cholesterol (p = 0.034) and triglycerides levels (p = 0.007).

CONCLUSIONS

This report is the first to show an association between RAAS-related gene variants and their relation with the biochemical characteristics of PAD and suggests that RAAS-associated gene variants may have significant roles in cardiovascular related phenotypes of PAD patients.

Searching for the Genetic Determinants of Peripheral Arterial Disease: A Review of the Literature and Future Directions

Peripheral arterial disease (PAD) is a significant but under-recognized disease that is poorly understood despite population-scale genetic studies. To address this morbid disease, clinicians need additional tools to identify, prevent, and treat patients at risk for PAD. Genetic studies of coronary artery disease have yielded promising results for clinical application, which have thus far been lacking in PAD. In this article, we review recent findings, discuss limitations, and propose future directions of genomic study and clinical application. However, despite many studies, we still lack definitive genetic markers for PAD. This can be attributed to the heterogeneity of PAD's pathogenesis and clinical manifestations, as well as inconsistencies in study methodologies, limitations of current genetic assessment techniques, incompletely comprehended molecular pathophysiology, and confounding generalized atherosclerotic risk factors. The goals of this review are to evaluate the limitations of our current genetic knowledge of PAD and to propose approaches to expedite the identification of valuable markers of PAD.

Increased Expression of Interleukin-18 mRNA is Associated with Carotid Artery Stenosis

Background:

Carotid artery stenosis is the atherosclerotic narrowing of the proximal internal carotid artery and one of the primary causes of stroke. Elevated expression of the pleiotropic proinflammatory cytokine interleukin-18 has been demonstrated in human atherosclerotic plaques.

Aims:

To investigate whether the mRNA expression levels of interleukin-18 and interleukin-18-binding protein and interleukin-18 −137 G/C (rs187238) variants are associated with carotid artery stenosis development.

Study Design:

Case-control study.

Methods:

The mRNA expression levels of interleukin-18 and interleukin-18-binding protein and interleukin-18 rs187238 variants were evaluated by quantitative real-time polymerase chain reaction and real-time polymerase chain reaction, respectively, in the peripheral blood mononuclear cells of 70 patients with carotid artery stenosis (36 symptomatic, 34 asymptomatic) and 75 healthy controls.

Results:

Interleukin-18 mRNA expression was significantly increased in carotid artery stenosis patients compared to that in healthy controls (p=0.01). However, no significant difference was observed between interleukin-18-binding protein mRNA expression levels in patients with carotid artery stenosis and those in controls (p=0.101). Internal carotid artery stenosis severity was significantly higher in symptomatic patients than that in asymptomatic patients (p<0.001). A significant relationship was identified between interleukin-18 expression and internal carotid artery stenosis severity in patients with carotid artery stenosis (p=0.051). Interleukin-18 rs187238 polymorphism genotype frequencies did not significantly differ between patients with carotid artery stenosis and controls (p=0.246). A significant difference was identified between interleukin-18-binding protein gene expression and symptomatic and asymptomatic patients (p=0.026), but there was no difference in interleukin-18 expression between the symptomatic and asymptomatic subgroups (p=0.397).

Conclusion:

Interleukin-18 mRNA expression may affect carotid artery stenosis etiopathogenesis and internal carotid artery stenosis severity and also may play a mechanistic role in the pathogenesis of carotid artery stenosis, influencing the appearance of symptoms.

The roles of interleukins in perfusion recovery after peripheral arterial disease

In peripheral arterial disease (PAD) patients, occlusions in the major arteries that supply the leg makes blood flow dependent on the capacity of neovascularization. There is no current medication that is able to increase neovascularization to the ischemic limb and directly treat the primary problem of PAD. An increasing body of evidence supports the notion that inflammation plays an important role in the vascular remodeling and perfusion recovery after PAD. Interleukins (ILs), a group of proteins produced during inflammation, have been considered to be important for angiogenesis and arteriogenesis after tissue ischemia. This review summarizes the latest clinical and experimental developments of the role of ILs in blood perfusion recovery after PAD.

The Discovery of Novel Genomic, Transcriptomic, and Proteomic Biomarkers in Cardiovascular and Peripheral Vascular Disease: The State of the Art

Cardiovascular disease (CD) and peripheral vascular disease (PVD) are leading causes of mortality and morbidity in western countries and also responsible of a huge burden in terms of disability, functional decline, and healthcare costs. Biomarkers are measurable biological elements that reflect particular physiological or pathological states or predisposition towards diseases and they are currently widely studied in medicine and especially in CD. In this context, biomarkers can also be used to assess the severity or the evolution of several diseases, as well as the effectiveness of particular therapies. Genomics, transcriptomics, and proteomics have opened new windows on disease phenomena and may permit in the next future an effective development of novel diagnostic and prognostic medicine in order to better prevent or treat CD. This review will consider the current evidence of novel biomarkers with clear implications in the improvement of risk assessment, prevention strategies, and medical decision making in the field of CD.