Biomarkers in unstable carotid plaque: Physiopathology and Prediction

Characterization of the proteome of stable and unstable carotid atherosclerotic plaques using data-independent acquisition mass spectrometry

BACKGROUND

Currently, noninvasive imaging techniques and circulating biomarkers are still insufficient to accurately assess carotid plaque stability, and an in-depth understanding of the molecular mechanisms that contribute to plaque instability is still lacking.

METHODS

We established a clinical study cohort containing 182 patients with carotid artery stenosis. After screening, 39 stable and 49 unstable plaques were included in the discovery group, and quantitative proteomics analysis based on data independent acquisition was performed for these plaque samples. Additionally, 35 plaques were included in the validation group to validate the proteomics results by immunohistochemistry analysis.

RESULTS

A total of 397 differentially expressed proteins were identified in stable and unstable plaques. These proteins are primarily involved in ferroptosis and lipid metabolism-related functions and pathways. Plaque validation results showed that ferroptosis- and lipid metabolism-related proteins had different expression trends in stable plaques versus unstable fibrous cap regions and lipid core regions. Ferroptosis- and lipid metabolism-related mechanisms in plaque stability were discussed.

CONCLUSIONS

Our results may provide a valuable strategy for revealing the mechanisms affecting plaque stability and will facilitate the discovery of specific biomarkers to broaden the therapeutic scope.

Homocysteine Combined with Apolipoprotein B as Serum Biomarkers for Predicting Carotid Atherosclerosis in the Oldest-Old

Background

The measurement of serum biomarkers is a promising decision aid in the assessment of atherosclerosis. However, data on the levels and epidemiological distribution of serum biomarkers of carotid atherosclerosis (CAS) in the oldest-old are limited. This study aimed to investigate the characteristics of CAS serum biomarkers in the oldest-old over 80 and explore their predictive value for CAS.

Methods

As part of the China Hainan Centenarian Cohort Study, a total of 1565 individuals over 80 years old were included. Atherosclerosis was assessed by carotid plaque and carotid intima-media thickness. Serum biomarker levels, demographic indicators, and physical examination indicators were detected. Prediction factors correlated to the CAS were explored by logistic regression and verified by receiver operating characteristic curve analysis. Multivariate regression models were fitted, along with subgroup analysis and robustness tests.

Results

Among the oldest-old population, 83.5% (1306) had CAS. In a fully adjusted multivariate logistic regression model, systolic blood pressure (SBP), heart rhythm (HR), serum homocysteine (Hcy), and apolipoprotein B (ApoB) levels were significantly and positively associated with CAS in the oldest-old (PS < 0.001). ROC analysis indicated that the combination of serum Hcy, ApoB, SBP, and HR increased the predictive value for CAS in the oldest-old (area under the curve: 0.856, 95% CI: 0.803-0.879; sensitivity: 81.8%; specificity: 85.9%).

Conclusion

SBP, HR, Hcy and ApoB are independent risk factors for CAS in the oldest-old. The specific set of biomarkers and their combination with other risk markers may be a promising strategy for assessing CAS in the elderly, especially in global aging.

Update on Biomarkers Associated with Large-Artery Atherosclerosis Stroke

Intracranial and extracranial large-artery atherosclerosis (LAA) are a main cause of ischemic stroke. Biomarkers may aid in the diagnosis of LAA and help to stratify patients' risk of stroke. We performed a narrative review of the literature, mainly published in the last five years, with the aim of identifying biomarkers associated either with intracranial or extracranial LAA in humans. Several potential biomarkers of LAA, mainly related to lipidic pathways and inflammation, have been studied. Diagnostic biomarkers of LAA were evaluated by measuring biomarkers levels in patients with LAA stroke and other stroke etiologies. Some biomarkers were associated with the functional prognosis of LAA stroke patients. Increased levels of IL-6 and sLOX-1 were associated with a risk of progression of carotid atherosclerotic disease. Findings support the notion that the immune system plays a central role in the pathogenesis of LAA. Overall, in most studies, results were not externally validated. In the future, biomarkers could be useful for the selection of patients for clinical trials. To adopt these biomarkers in clinical practice, we will need robust multicentric studies proving their reproducibility and a clear practical applicability for their use.