Using Mendelian Randomization studies to Assess Causality and Identify New Therapeutic Targets in Cardiovascular Medicine

Stress-Induced Hypercoagulability: Insights from Epidemiological and Mechanistic Studies, and Clinical Integration

By integrating findings from comprehensive reviews, meta-analyses, and cutting-edge genetic studies, this article illuminates the significance of stress-induced hypercoagulability in clinical medicine. In particular, the findings from numerous prospective cohort studies indicate that stress and hemostatic factors of a hypercoagulable state are associated with increased incident risk and poor prognosis for atherosclerotic cardiovascular disease and venous thromboembolism. Mendelian randomization studies suggest that these associations are partially causal. The review synthesizes extensive research on the link between acute and chronic stress and hypercoagulability, outlining a potential pathway from stress to thrombosis risk. Consistent with the allostatic load concept, acute stress-induced hypercoagulability, initially adaptive, can turn maladaptive under chronic stress or excessive acute stress, leading to arterial or venous thrombotic events. Individuals with predisposing factors, including atherosclerosis, thrombophilia, or immobilization, may exhibit an increased risk of thrombotic disease during stress. Contextual sociodemographic characteristics, the stress experience, and coping resources additionally modulate the extent of stress-induced hypercoagulability. Research into the neuroendocrine, cellular, and molecular bases reveals how stress influences platelet activation coagulation and fibrinolysis. The activation of the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis, along with vagal withdrawal, and the effects of catecholamines, cortisol, and vasopressin, are the central mechanisms involved. Hemoconcentration, inflammation, endothelial dysfunction, and thrombopoiesis additionally contribute to stress-induced hypercoagulability. Further research is needed to prove a causal link between chronic stress and hypercoagulability. This includes exploring its implications for the prevention and management of thrombotic diseases in stressed individuals, with a focus on developing effective psychosocial and pharmacological interventions.

Chemopreventive Agents After Pancreatic Resection for Ductal Adenocarcinoma: Legend or Scientific Evidence?

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is currently the fourth leading cause of cancer-related death in the USA. A wealth of evidence has demonstrated the chemopreventive activity of aspirin, statins, and metformin against PDAC. The aim of this study is to investigate the effect of aspirin, statins, and metformin on disease-free survival (DFS) and disease-specific survival (DSS) in a large population of PDAC patients undergoing pancreatic resection.

PATIENTS AND METHODS

All patients who underwent pancreatic resections between January 2015 and September 2018 were retrospectively reviewed. The potentially "chemopreventive agents" considered for the analysis were aspirin, statins, and metformin. Drug use was defined in case of regular assumption at least 6 months before diagnosis and regularly after surgery along the follow-up period.

RESULTS

A total of 430 patients were enrolled in this study, with median DFS and DSS of 21 months (IQR 13-30) months and 34 (IQR 26-52) months, respectively. On multivariable analysis, use of aspirin was associated with better DFS (HR: 0.62; p = 0.038). Metformin was associated with better DFS, without reaching statistical significance (p = 0.083). Use of statins did not influence DFS in the studied population. Aspirin, metformin, and statins were not associated with better DSS on multivariable analysis. Factors influencing DSS were pT3/pT4, N1, N2, no adjuvant treatment, G3, and ASA score > 3.

CONCLUSIONS

The results suggest that chronic use of aspirin is associated with increased DFS but not with better DSS after surgical resection in patients with PDAC.

Rosmarinic acid inhibits nicotine-induced C-reactive protein generation by inhibiting NLRP3 inflammasome activation in smooth muscle cells

Atherosclerosis is widely known to be a chronic inflammatory disease. C-reactive protein (CRP), an important inflammatory factor, plays an essential role in the pathogenesis of atherosclerosis. Nicotine, the main addictive component of cigarette, has been shown to induce the production of CRP. The aim of this study was to investigate the effect of rosmarinic acid (RA), a polyphenol with antiinflammatory activity, on nicotine-induced elevation of CRP in vascular smooth muscle cells (VSMCs). We found that pretreatment of VSMCs with RA attenuated nicotine-induced expression of CRP in a time- and dose-dependant manner. In addition, RA also inhibited the activation of NLR family pyrin domain containing 3 (NLRP3) inflammasome and reactive oxygen species (ROS) production resulting from nicotine treatment in VSMCs. To confirm these findings in vivo, we constructed a nicotine-induced atherosclerosis rat model. RA did not significantly reduce the serum nicotine level of the rats, whereas it significantly decreased the levels of serum lipids, including concentrations of cholesterol, triglycerides, and low-density lipoprotein cholesterol, and the serum level of CRP. RA also led to diminished nicotine-induced activation of NLRP3 inflammasome and elevation in the CRP level in the aortic tissue of the model rats. The results of this study suggested a protective role of RA in nicotine-induced atherosclerosis by inhibiting the ROS-NLRP3 inflammasome-CRP axial, and RA therefore represented a potential effective therapeutic approach to atherosclerosis, in particular for those who smoke.

Genome-wide mapping of plasma protein QTLs identifies putatively causal genes and pathways for cardiovascular disease

Identifying genetic variants associated with circulating protein concentrations (protein quantitative trait loci; pQTLs) and integrating them with variants from genome-wide association studies (GWAS) may illuminate the proteome's causal role in disease and bridge a knowledge gap regarding SNP-disease associations. We provide the results of GWAS of 71 high-value cardiovascular disease proteins in 6861 Framingham Heart Study participants and independent external replication. We report the mapping of over 16,000 pQTL variants and their functional relevance. We provide an integrated plasma protein-QTL database. Thirteen proteins harbor pQTL variants that match coronary disease-risk variants from GWAS or test causal for coronary disease by Mendelian randomization. Eight of these proteins predict new-onset cardiovascular disease events in Framingham participants. We demonstrate that identifying pQTLs, integrating them with GWAS results, employing Mendelian randomization, and prospectively testing protein-trait associations holds potential for elucidating causal genes, proteins, and pathways for cardiovascular disease and may identify targets for its prevention and treatment.

Genetics of Subclinical Coronary Atherosclerosis

Purpose of Review

This review highlights recent findings regarding genetics of coronary artery calcification (CAC), a marker of subclinical atherosclerosis burden, that is a precursor of clinical coronary artery disease.

Recent findings

CAC quantity is heritable. Genome wide association studies of common single nucleotide polymorphisms have identified genomic regions explaining ~2.4% of CAC heritability. Low frequency and rare variants explain additional variation in CAC. Evidence suggests that there may be different genetic etiologies for variation in CAC progression than for cross-sectional measures of CAC. Studies integrating multiple -omics data are providing new insights into the pathobiology of subclinical coronary atherosclerosis.

Summary

The future is promising for innovative studies utilizing whole genome sequencing data as well as other -omics such as epigenomic modifications of genes and gene expression. These studies may provide multiple sources of data pointing to the same gene or pathway, thus providing greater confidence in findings.