A Comprehensive Review of the Pleiotropic Effects of Ticagrelor

AIMS

This review summarizes the findings of preclinical studies evaluating the pleiotropic effects of ticagrelor. These include attenuation of ischemia-reperfusion injury (IRI), inflammation, adverse cardiac remodeling, and atherosclerosis. In doing so, it aims to provide novel insights into ticagrelor's mechanisms and benefits over other P2Y12 inhibitors. It also generates viable hypotheses for the results of seminal clinical trials assessing ticagrelor use in acute and chronic coronary syndromes.

METHODS AND RESULTS

A comprehensive review of the preclinical literature demonstrates that ticagrelor protects against IRI in the setting of both an acute myocardial infarction (MI), and when MI occurs while on chronic treatment. Maintenance therapy with ticagrelor also likely mitigates adverse inflammation, cardiac remodeling, and atherosclerosis, while improving stem cell recruitment. These effects are probably mediated by ticagrelor's ability to increase local interstitial adenosine levels which activate downstream cardio-protective molecules. Attenuation and augmentation of these pleiotropic effects by high-dose aspirin and caffeine, and statins respectively may help explain variable outcomes in PLATO and subsequent randomized controlled trials (RCTs).

CONCLUSION

Most RCTs and meta-analyses have not evaluated the pleiotropic effects of ticagrelor. We need further studies comparing cardiovascular outcomes in patients treated with ticagrelor versus other P2Y12 inhibitors that are mindful of the unique pleiotropic advantages afforded by ticagrelor, as well as possible interactions with other therapies (e.g., aspirin, statins, caffeine).

Analysis of Biodistribution and in vivo Toxicity of Varying Sized Polystyrene Micro and Nanoplastics in Mice

Introduction

Studies have shown that microplastics (MPs) and nanoplastics (NPs) could accumulate in the human body and pose a potential threat to human health. The purpose of this study is to evaluate the biodistribution and toxicity of MPs/NPs with different particle sizes comprehensively and thoroughly.

Methods

The purpose of this study was to investigate the biodistribution and in vivo toxicity of polystyrene (PS) MPs/NPs with different sizes (50 nm, 100 nm, and 500 nm). The BALB/c mice were given 100 μL of PS50, PS100 and PS500 at the dosage of 1 mg/kg BW or 10 mg/kg BW, respectively, by gavage once a day. After 28 consecutive days of treatment, the biodistribution of differently sized PS MPs/NPs was determined through cryosection fluorescence microscopy and fluorescent microplate reader analysis, and the subsequent effects of differently sized PS MPs/NPs on histopathology, hematology and blood biochemistry were also evaluated.

Results

The results showed that the three different sizes of PS MPs/NPs were distributed in the organs of mice, mainly in the liver, spleen, and intestine. At the same time, the smaller the particle size, the more they accumulate in the body and more easily penetrate the tissue. During the whole observation period, no abnormal behavior and weight change were observed. The results of H&E staining showed that no severe histopathological abnormalities were observed in the main organs in the low-dose exposure group, while. Exposure of three sizes of PS MPs/NPs could cause some changes in hematological parameters or biochemical parameters related to heart, liver, and kidney function; meanwhile, there were size- and dose-dependencies.

Conclusion

The biological distribution and toxicity of plastic particles in mice were more obvious with the decrease of particle size and the increase of concentration of plastic particles. Compared with MPs, NPs were easier to enter the tissues and produce changes in liver, kidney, and heart functions. Therefore, more attention should be paid to the toxicity of NPs.

Oxidized/unmodified-polyethylene microplastics neurotoxicity in mice: Perspective from microbiota-gut-brain axis

Microplastics (MPs) are inevitably oxidized in the environment, and their potential toxicity to organisms has attracted wide attention. However, the neurotoxicity and mechanism of oxidized polyethylene (Ox-PE) MPs to organisms remain unclear. Herein, we prepared oxidized low-density polyethylene (Ox-LDPE) and established a model of MPs exposure by continuously orally gavage of C57BL/6 J mice with LDPE-MPs/Ox-LDPE-MPs for 28 days with or without oral administration of Lactobacillus plantarum DP189 and galactooligosaccharides (DP189&GOS). The experimental results indicated that LDPE-MPs or Ox-LDPE-MPs caused several adverse effects in mice, mainly manifested by behavioral changes, disruption of the intestinal and blood-brain barrier (BBB), and simultaneous oxidative stress, inflammatory reactions, and pathological damage in the brain and intestines. Brain transcriptomic analysis revealed that the cholinergic synaptic signaling pathways, which affect cognitive function, were significantly disrupted after exposure to LDPE-MPs or Ox-LDPE-MPs. Real-time quantitative polymerase chain reaction and Western Blotting results further demonstrated that the critical genes (Slc5a7, Chat and Slc18a3) and proteins (Chat and Slc18a3) in the cholinergic synaptic signaling pathway were significantly down-regulated after exposure to LDPE-MPs or Ox-LDPE-MPs. These alterations lead to reduced acetylcholine concentration, which causes cognitive dysfunction in mice. Importantly, the DP189&GOS interventions effectively mitigated the MPs-induced cognitive dysfunction and intestinal microbiota alteration, improved intestinal and BBB integrity, attenuated the oxidative stress and inflammatory response, and also saw a rebound in the release of acetylcholine. These results indicated that LDPE-MPs and Ox-LDPE-MPs exert neurotoxic effects on mice by inducing oxidative stress, inflammatory responses, and dysregulation of cholinergic signaling pathways in the mouse brain. That probiotic supplementation is effective in attenuating MPs-induced neurotoxicity in mice. Overall, this study reveals the potential mechanisms of neurotoxicity of LDPE-MPs and Ox-LDPE-MPs on mice and their improvement measures, necessary to assess the potential risks of plastic contaminants to human health.

White blood cell count combined with LDL cholesterol as a valuable biomarker for coronary artery disease

OBJECTIVE

Inflammation and dyslipidemia are important pathophysiological bases for the occurrence and development of coronary artery disease (CAD); however, combination of these two entities is rarely used to diagnose CAD and its severity. Our aim was to determine whether the combination of white blood cell count (WBCC) and LDL cholesterol (LDL-C) can serve as a biomarker for CAD.

METHODS

We enrolled 518 registered patients and measured serum WBCC and LDL-C on admission. The clinical data were collected, and the Gensini score was used to assess the severity of coronary atherosclerosis.

RESULTS

WBCC and LDL-C levels in the CAD group were higher than in the control group ( P  < 0.01). Spearman correlation analysis showed that WBCC combined with LDL-C was positively correlated with the Gensini score ( r  = 0.708, P  < 0.01) and the number of coronary artery lesions ( r  = 0.721, P  < 0.01). Receiver operating characteristic curve analysis revealed that WBCC combined with LDL-C had a higher predictive value for CAD, severe CAD, and three-vessel CAD [area under the curve (AUC) values were 0.909, 0.867, and 0.811, respectively] than WBCC (AUC values were 0.814, 0.753, 0.716, respectively) and LDL-C (AUC values were 0.779, 0.806, 0.715, respectively) alone (all P  < 0.05).

CONCLUSION

WBCC combined with LDL-C is correlated with the degree of coronary artery lesion. It had high sensitivity and specificity in the diagnosis of CAD, severe CAD, and three-vessel CAD.

P2Y12 inhibitor monotherapy in patients undergoing percutaneous coronary intervention

For 20 years, dual antiplatelet therapy (DAPT), consisting of the combination of aspirin and a platelet P2Y₁₂ receptor inhibitor, has been the gold standard of antithrombotic pharmacology after percutaneous coronary intervention (PCI). In the past 5 years, several investigations have challenged this paradigm by testing the efficacy and safety of P2Y₁₂ inhibitor monotherapy (that is, without aspirin) following a short course of DAPT. Collectively, these studies suggested a reduction in the risk of major bleeding and no significant increase in thrombotic or ischaemic events compared with guideline-recommended DAPT. Current recommendations are evolving to inform clinical practice on the ideal candidates for P2Y₁₂ inhibitor monotherapy after PCI. Generalizing the results of studies of P2Y₁₂ inhibitor monotherapy requires a thorough understanding of their design, populations, interventions, comparators and results. In this Review, we provide an up-to-date overview on the use of P2Y₁₂ inhibitor monotherapy after PCI, including supporting pharmacodynamic and clinical evidence, practical recommendations and future directions.

Impact of preprocedural biological markers on 10-year mortality in the SYNTAXES trial

BACKGROUND

Creatinine clearance (CrCl) is an independent determinant of mortality in predictive models of revascularisation outcomes for complex coronary artery disease.

AIMS

This study aimed to investigate the impact of preprocedural biological markers on 10-year mortality following coronary revascularisation.

METHODS

The SYNTAX Extended Survival (SYNTAXES) study evaluated the 10-year vital status follow-up of 1,800 patients with de novo three-vessel (3VD) and/or left main coronary artery disease (LMCAD) randomised to include percutaneous or surgical coronary revascularisation. The associations between mortality and preprocedural C-reactive protein (CRP), haemoglobin, HbA1c, CrCl, fasting triglycerides, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol were analysed.

RESULTS

Out of 1,800 patients, 460 patients died before the 10-year follow-up. CRP, HbA1c and CrCl with threshold values of ≥2 mg/L, ≥6% (42 mmol/mol) and <60 ml/min, respectively, were associated with 10-year all-cause death (adjusted hazard ratio [95% confidence interval]: 1.35 [1.01-1.82], 1.51 [1.16-1.95], and 1.46 [1.07-2.00], respectively). There was no significant interaction between the biological markers on all-cause mortality and the type of revascularisation. Preprocedural lipid markers were not significantly associated with 10-year all-cause death, but the non-use of statins was a determinant factor of worse prognosis (adjusted hazard ratio [95% confidence interval]: 1.68 [1.26-2.25]).

CONCLUSIONS

Preprocedural biomarkers, such as CRP and HbA1c, are associated with long-term mortality post revascularisation, regardless of the revascularisation technique. Conventional lipidic biomarkers associated with high-risk of cardiovascular events seem to be effectively mitigated by the long-term use of statins, whereas the non-use of statins was a factor of a worse prognosis, emphasising the importance of pharmacological treatment.

TRIAL REGISTRATION

SYNTAXES ClinicalTrials.gov: NCT03417050. SYNTAX ClinicalTrials.gov: NCT00114972.

The Association Between High CHA2DS2-VASc Scores and Short and Long-Term Mortality for Coronary Care Unit Patients

Background

The CHA₂DS₂-VASc score has been associated with the prognosis of cardiovascular diseases. This study aimed to explore the association between the CHA₂DS₂-VASc score and all-cause mortality in coronary care unit (CCU) patients.

Methods

The study was based on the Medical Information Mart for Intensive Care (MIMIC) III database. CCU patients were divided into two groups according to CHA₂DS₂-VASc score: 0-3 (low risk)，4-9 (intermediate and high risk). The primary outcome was 30-day mortality, and the secondary endpoints included in-hospital, 1-year, and 5-year mortality. Propensity score matching (PSM) and sensitivity analyzes for the confounders were also performed. The restricted cubic splines flexibility model was used to demonstrate the relation between red blood cell volume distribution width (RDW), blood urea nitrogen (BUN), platelet, white blood cell (WBC), hemoglobin, phosphorus, glucose, potassium, sodium and 30-day mortality in the 0-3 score versus the 4-9 score groups after PSM.

Results

Among 4491 eligible patients, 988 patients with low CHA₂DS₂-VASc scores and 988 patients with intermediate and high CHA₂DS₂-VASc scores had similar propensity scores and were included in the analyzes. In the survival analysis, the patients with intermediate and high CHA₂DS₂-VASc scores were associated with higher 30-day mortality [hazard ratio (HR): 1.11; 95% confidence interval (CI), 1.02–1.20, P = .014], 1-year mortality [HR: 1.13; 95%CI, 1.06–1.19, P < .001], and 5-year mortality [HR: 1.13; 95%CI, 1.07–1.18, P < .001]. The interaction for 30-day mortality among subgroups was not significant between the 0-3 score versus the 4-9 score groups. The restricted cubic splines for 30-day mortality demonstrated an L-shaped trajectory for platelets and hemoglobin, a J-shaped trajectory for WBC, glucose and potassium, and a U-shaped trajectory for sodium, respectively (all nonlinear P <.001).

Conclusions

A high CHA₂DS₂-VASc score was an independent risk for 30-day, 1-year, and 5-year mortality for CCU patients.

Aspirin-free antiplatelet regimens after PCI: insights from the GLOBAL LEADERS trial and beyond

Historically, aspirin has been the primary treatment for the prevention of ischaemic events in patients with coronary artery disease. For patients undergoing percutaneous coronary intervention (PCI) standard treatment has been 12 months of dual antiplatelet therapy (DAPT) with aspirin and clopidogrel, followed by aspirin monotherapy; however, DAPT is undeniably associated with an increased risk of bleeding. For over a decade novel P2Y₁₂ inhibitors, which have increased specificity, potency, and efficacy have been available, prompting studies which have tested whether these newer agents can be used in aspirin-free antiplatelet regimens to augment clinical benefits in patients post-PCI. Among these studies, the GLOBAL LEADERS trial is the largest by cohort size, and so far has provided a wealth of evidence in a variety of clinical settings and patient groups. This article summarizes the state-of-the-art evidence obtained from the GLOBAL LEADERS and other trials of aspirin-free strategies.