The Multifaceted Clinical Readouts of Platelet Inhibition by Low-Dose Aspirin

Low-dose aspirin, maternal cardiometabolic health, and offspring respiratory health 9 to 14 years after delivery: Findings from the EAGeR Follow-up Study

BACKGROUND

Accumulating evidence shows that peri-conceptional and in-utero exposures have lifetime health impacts for mothers and their offspring.

OBJECTIVES

We conducted a Follow-Up Study of the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial with two objectives. First, we determined if women who enrolled at the Utah site (N = 1001) of the EAGeR trial (2007-2011, N = 1228) could successfully be contacted and agree to complete an online questionnaire on their reproductive, cardio-metabolic, and offspring respiratory health 9-14 years after original enrollment. Second, we evaluated if maternal exposure to low-dose aspirin (LDA) during pregnancy was associated with maternal cardio-metabolic health and offspring respiratory health.

METHODS

The original EAGeR study population included women, 18-40 years of age, who had 1-2 prior pregnancy losses, and who were trying to become pregnant. At follow-up (2020-2021), participants from the Utah cohort completed a 13-item online questionnaire on reproductive and cardio-metabolic health, and those who had a live birth during EAGeR additionally completed a 7-item questionnaire on the index child's respiratory health. Primary maternal outcomes included hypertension and hypercholesterolemia; primary offspring outcomes included wheezing and asthma.

RESULTS

Sixty-eight percent (n = 678) of participants enrolled in the follow-up study, with 10% and 15% reporting maternal hypertension and hypercholesterolemia, respectively; and 18% and 10% reporting offspring wheezing and asthma. We found no association between maternal LDA exposure and hypertension (risk difference [RD] -0.001, 95% confidence interval [CI] -0.05, 0.04) or hypercholesterolemia (RD -0.01, 95% CI -0.06, 0.05) at 9-14 years follow-up. Maternal LDA exposure was not associated with offspring wheezing (RD -0.002, 95% CI -0.08, 0.08) or asthma (RD 0.13, 95% CI 0.11, 0.37) at follow-up. Findings remained robust after considering potential confounding and selection bias.

CONCLUSIONS

We observed no association between LDA exposure during pregnancy and maternal cardiometabolic or offspring respiratory health.

Effect of Low-Dose Aspirin on the Elderly

Aspirin is a recognized and affordable antiplatelet medicine. Low amounts of aspirin have been used to prevent cardiovascular events, and it is still widely used for primary and secondary stroke prevention. The purpose of this review article is to evaluate the effects of using low doses of aspirin among elderly people. Although taking large dosages of aspirin (500 mg daily) reduces the long-term risk of colorectal cancer, its effectiveness for long-term prevention may be limited by adverse effects. Studies have assessed the relationship between aspirin dosage, incidence, and death in patients with colorectal cancer. Research has indicated that those with diabetes mellitus have an increased risk of cardiovascular events. Low amounts of aspirin have been used to prevent cardiovascular events. However, there is uncertainty regarding the potential benefits and risks associated with preventing the development of cardiovascular problems in individuals with diabetes. The use of aspirin lowers the risk of occlusive vascular events but raises the possibility of bleeding. More attention should be paid to reducing inappropriate aspirin usage in light of its prevalence, particularly among older persons, as the substantial continuous usage of this drug increases the chances of bleeding.

Contemporaneous Perioperative Inflammatory and Angiogenic Cytokine Profiles of Surgical Breast, Colorectal, and Prostate Cancer Patients: Clinical Implications

Surgery-induced tumor growth acceleration and synchronous metastatic growth promotion have been observed for decades. Surgery-induced wound healing, orchestrated through growth factors, chemokines, and cytokines, can negatively impact patients harboring residual or metastatic disease. We provide detailed clinical evidence of this process in surgical breast, prostate, and colorectal cancer patients. Plasma samples were analyzed from 68 cancer patients who had not received treatment before surgery or adjuvant therapy until at least four weeks post-surgery. The levels of plasma cytokines, chemokines, and growth factors were simultaneously quantified and profiled using multiplexed immunoassays for eight time points sampled per patient. The immunologic processes are induced immediately after surgery in patients, characterized by a drastic short-term shift in the expression levels of pro-inflammatory and angiogenic molecules and cytokines. A rapid and significant spike in circulating plasma levels of hepatocyte growth factor (HGF), interleukin-6 (IL-6), placental growth factor (PLGF), and matrix metalloproteinase-9 (MMP-9) after surgery was noted. The rise in these molecules was concomitant with a significant drop in transforming growth factor-β1 (TGF-β1), platelet-derived growth factor (PDGF-AB/BB), insulin-like growth factor-1 (IGF-1), and monocyte chemoattractant protein-2 (MCP-2). If not earlier, each plasma analyte was normalized to baseline levels within 1-2 weeks after surgery, suggesting that surgical intervention alone was responsible for these effects. The effects of surgical tumor removal on disrupting the pro-inflammatory and angiogenic plasma profiles of cancer patients provide evidence for potentiating malignant progression. Our findings indicate a narrow therapeutic window of opportunity after surgery to prevent disease recurrence.

Targeting memory loss with aspirin, a molecular mechanism perspective for future therapeutic approaches

Acetylsalicylic acid (ASA), also known as aspirin, was discovered in 1897 as an acetylated form of salicylate. It has been widely used for its anti-inflammatory and antiplatelet effects. It is commonly used for its cardiovascular benefits and is prescribed as secondary prophylaxis after a heart attack. Furthermore, low-dose, long-term ASA is used to reduce the risk of heart attack and stroke in individuals without prior cardiovascular disease. Acetylsalicylic acid acts as a non-selective inhibitor of cyclooxygenase (COX), which inhibits the synthesis of prostaglandins and prevents pro-inflammatory cytokines. Findings suggest that targeting cytokines and growth factors could be a potential therapeutic strategy for reducing neuroinflammation and slowing down the progression of dementia. Additionally, prostaglandins contribute to synaptic plasticity and can act as retrograde messengers in synapses. Research has implicated COX-1, one of the isoforms of the enzyme, in neuroinflammation and neurodegenerative disorders. The inhibition of COX-1 might potentially prevent impairments in working memory and reduce neuroinflammation caused by beta-amyloid proteins in some conditions, such as Alzheimer's disease (AD). Cyclooxygenase-2, an inducible form of the enzyme, is expressed in cortical and hippocampal neurons and is associated with long-term synaptic plasticity. The inhibition or knockout of COX-2 has been shown to decrease long-term potentiation, a process involved in memory formation. Studies have also demonstrated that the administration of COX-2 inhibitors impairs cognitive function and memory acquisition and recall in animal models. There remains a debate regarding the effects of aspirin on dementia and cognitive decline. Although some studies suggest a possible protective effect of non-steroidal anti-inflammatory drugs, including aspirin, against the development of AD, others have shown inconsistent evidence. This review provides an overview of the effects of ASA or its active metabolite salicylate on learning, memory, and synaptic plasticity.

Alpinia katsumadai Hayata Volatile Oil Is Effective in Treating 5-Fluorouracil-Induced Mucositis by Regulating Gut Microbiota and Modulating the GC/GR Pathway and the mPGES-1/PGE2/EP4 Pathways

This study was aimed to investigate the therapeutic effect and mechanism of AKHO on 5-fluorouracil (5-FU)-induced intestinal mucositis in mice. Mouse body weight, diarrhea score, and H&E staining were applied to judge the therapeutic effect of AKHO. 16S rDNA and nontargeted metabolomics have been used to study the mechanism. WB, ELISA, and immunohistochemistry were adopted to validate possible mechanisms. The results demonstrated that AKHO significantly reduced diarrhea scores and intestinal damage induced by 5-FU in mice. AKHO lowered the serum levels of LD and DAO, and upregulated the expressions of ZO-1 and occludin in the ileum. Also, AKHO upregulated the abundance of Lactobacillus in the gut and suppressed KEGG pathways such as cortisol synthesis and secretion and arachidonic acid metabolism. Further validation studies indicated that AKHO downregulated the expressions of prostaglandin E2 (PGE2), microsomal prostaglandin E synthase-1 (mPGES-1), and PGE2 receptor EP4, as well as upregulated the expression of glucocorticoid (GC) receptor (GR), leading to improved intestinal epithelial barrier function. Taken together, AKHO elicited protective effects against 5-FU-induced mucositis by regulating the expressions of tight junction proteins via modulation of GC/GR and mPGES-1/PGE2/EP4 pathway, providing novel insights into the utilization and development of this pharmaceutical/food resource.

Exploring the potential of quercetin/aspirin-loaded chitosan nanoparticles coated with Eudragit L100 in the treatment of induced-colorectal cancer in rats

Growing evidence suggests quercetin and aspirin may have anticancer properties, notably in the case of colorectal cancer. The goal of this study was to create Pluronic F127 and polyethylene glycol4000 solid dispersion-loaded chitosan nanoparticles for colonic quercetin and aspirin delivery. In 1:1 polymeric stoichiometric ratio, solubility and complex formation were verified. Solid dispersion-loaded chitosan nanoparticles with a diameter of 244.45 ± 8.5 nm, a surface charge of 34.1 ± 3.3 mV, and encapsulation effectiveness of 76.3 ± 4.3% were generated under ideal conditions. In some cases, coating with Eudragit L100 resulted in a decrease in zeta potential and an increase in particle size. The coated formulation released the actives in a pH-dependent manner, considering their physicochemical features. Surprisingly, when compared to the actives' suspension and uncoated formulation, the coated formulation had greater anti-inflammatory efficacy, with a substantial reduction of PGE2 and IL-8 production in colonic tissues (16.9 ± 7.9 ng/g tissue and 134.9 ± 10.1 pg/g tissue, respectively). It also reversed most of the dimethyl hydrazine-induced histological alterations in the colon. It also demonstrated a greater reduction in TNF expression in colonic tissues. As a result, Eudragit L100-coated QT/AS-loaded chitosan nanoparticles are suggested to provide a potential platform for colonic delivery of quercetin and aspirin.

Evaluation of impacts of aspirin therapy versus placebo on preeclampsia: An observational study

Background

Gestational hypertension and pre-eclampsia often increase maternal and neonatal mortality. The illness usually appears after the 20th week of pregnancy due to malnutrition or obesity. Untreated, it can lead to neonatal and maternal mortality. Low-dose Aspirin can prevent preeclampsia if started between 11 and 28 weeks. Several studies support this technique, although others have shown limited effectiveness and negative side effects.

Objective

This study aims to assess the effectiveness of aspirin treatment for the prevention of preeclampsia, taking into account any possible adverse reactions.

Methods

This observational research comprised 600 singleton pregnant women at high risk of pregnancy-induced hypertension. The aspirin group had 301 individuals and the placebo group 299. From 11 to 36 weeks of pregnancy, they received 150 mg of aspirin and 150 mg of placebo. Gestational hypertension was assessed at 25 weeks, 36 weeks, and 37 weeks. If any, aspirin and placebo-related adverse pregnancy and neonatal outcomes were reported.

Results

With aspirin therapy, 4 females and 14 females with placebo developed gestational hypertension before 25 weeks of pregnancy with an odds ratio of 0.283 (0.092-0.87); before 36 weeks, 5 females and 15 females with placebo developed GHD with an odds ratio of 0.331 (0.118-0.922); and after 37 weeks, 17 females and 35 females with placebo developed GHD. Preeclampsia occurred in 5 females in the aspirin group and 17 in the placebo group at <25 weeks (odds ratio 0.292 (0.106-0.802), 7 females in the aspirin arm and 25 females in the placebo arm at <36 weeks (odds ratio 0.278 (0.118-0.652), and 21 females in the aspirin arm and 39 females in the placebo arm at >37 weeks (odds ratio 0.5349 (0.307-0.930).

Conclusion

In pregnant women at high risk of prenatal hypertension and preeclampsia, aspirin therapy is very effective with minimal side effects.

Comparison of the Efficacy and Safety of Aspirin and Low-Molecular-Weight Heparin in Patients With a Fracture: A Meta-Analysis

The aim of this study is to compare the efficacy and safety of aspirin and low-molecular-weight heparin (LMWH) in preventing thromboembolic events in patients with fractures. The present meta-analysis was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched EMBASE, PubMed, and EBSCO to find articles comparing aspirin and LMWH in patients with orthopedic trauma from inception to April 15, 2023. Limits were set to studies published in the English language only. Outcomes assessed in this meta-analysis included VTE and all-cause mortality. VTE can manifest as deep venous thrombosis (DVT) and pulmonary embolism. For safety analysis, rates of wound complication, infection, and bleeding complications were compared between the two study groups. A total of three studies were included in this meta-analysis enrolling 12884 patients. The study found no significant difference between the two groups in the risk of DVT and pulmonary embolism, and aspirin was non-inferior to LMWH for the prevention of all-cause mortality in patients. Additionally, no significant safety risk was associated with aspirin thromboprophylaxis. These findings suggest that inexpensive over-the-counter aspirin is as effective as LMWH in terms of safety and efficacy profile, making it a feasible option to consider in clinical practice.

Aspirin prevents estrogen deficiency-induced bone loss by inhibiting osteoclastogenesis and promoting osteogenesis

BACKGROUND

Aspirin is a commonly used antipyretic, analgesic, and anti-inflammatory drug. Numerous researches have demonstrated that aspirin exerts multiple biological effects on bone metabolism. However, its spatiotemporal roles remain controversial according to the specific therapeutic doses used for different clinical conditions, and the detailed mechanisms have not been fully elucidated. Hence, in the present study, we aimed to identify the dual effects of different aspirin dosages on osteoclastic activity and osteoblastic bone formation in vitro and in vivo.

METHODS

The effects of varying doses of aspirin on osteoclast and osteoblast differentiation were evaluated in vitro. The underlying molecular mechanisms were detected using quantitative real-time polymerase chain reaction, western blotting, and immunofluorescence techniques. An ovariectomized rat osteoporosis model was used to assess the bone-protective effects of aspirin in vivo.

RESULTS

Aspirin dose-dependently suppressed RANKL-induced osteoclasts differentiation and bone resorption in vitro and reduced the expression of osteoclastic marker genes, including TRAP, cathepsin K, and CTR. Further molecular analysis revealed that aspirin impaired the RANKL-induced NF-κB and MAPK signaling pathways and prevented the nuclear translocation of the NF-κB p65 subunit. Low-dose aspirin promoted osteogenic differentiation, whereas these effects were attenuated when high-dose aspirin was administered. Both low and high doses of aspirin prevented bone loss in an ovariectomized rat osteoporosis model in vivo.

CONCLUSION

Aspirin inhibits RANKL-induced osteoclastogenesis and promotes osteogenesis in a dual regulatory manner, thus preventing bone loss in vivo. These data indicate that aspirin has potential applications in the prevention and treatment of osteopenia.

Prospective, randomized, controlled, trial to assess ASA DOSing by body mass index in HEalthy volunteers (DOSE study)

STUDY OBJECTIVE: Aspirin (ASA) has demonstrated inconsistent results in primary prevention of cardiovascular disease (CVD). Guidelines are also inconsistent in the recommendation of routine ASA use for primary prevention of CVD, but advocate dosing as a "one-size-fits-all" approach.

DESIGN

An intention-to-treat, double-blind, randomized, controlled, clinical trial comparing three treatment arms of ASA 81, 325, and 500 mg daily dosed for 14 days were evenly randomized across the dosing categories to measure the impact of dosing by body mass index (BMI) (20-24.9, 25-29.9, ≥30 kg/m² ) on ASA anti-platelet effects.

SETTING

University Ambulatory Clinic.

PATIENTS

Healthy volunteers defined as individuals who were medication free without acute or chronic significant health problems.

INTERVENTION

Change in ASA reactivity unit (ARU), salicylate levels, and thromboxane B2 (TxB2) levels were measured across BMI dosing categories and time. MAIN RESULTS: Fifty-four participants with a mean (±SD) age of 34.4 ± 10.9 years (M:F; 23:31) completed the study. Baseline ARU and TxB2 levels were not significantly different between obese and non-obese individuals. BMI was not a predictor of platelet inhibition. There was no interaction between gender and platelet activation at baseline or following ASA treatment. ASA 81 mg was associated with a lower ARU response (approximate 50% lower response) than either the 325-mg or the 500-mg doses of ASA. TxB2 and salicylate levels exhibited lower trends at 81 mg compared with higher doses.

CONCLUSIONS

In healthy male and female participants administered ASA for 14 days, obesity is not associated with increased basal platelet activation or ASA resistance. ASA 81 mg was significantly less effective in reducing platelet aggregation compared with ASA 325 and 500 mg, independent of BMI.

Fifty years with aspirin and platelets

In 2021, we reached the 50th anniversary of the publication of Sir John Vane's seminal paper in Nature New Biology describing the experiments supporting his mechanistic hypothesis that inhibition of prostaglandin synthesis might explain the main pharmacological effects of aspirin and aspirin-like drugs, that is, reduction in pain, fever and inflammation. Bengt Samuelsson's subsequent discoveries elucidating the cyclooxygenase pathway of platelet arachidonic acid metabolism motivated my research interest towards measuring platelet thromboxane A₂ biosynthesis as a tool to investigate the clinical pharmacology of cyclooxygenase inhibition by aspirin in health and disease. What followed was a long, winding road of clinical research leading to the characterization of low-dose aspirin as a life-saving antiplatelet drug that still represents the cornerstone of antithrombotic therapy. Having witnessed and participated in these 50 years of aspirin research, I thought of providing a personal testimony of how things developed and eventually led to a remarkable success story of independent research.

Low- or high-dose preventive aspirin use and risk of death from all-cause, cardiovascular disease, and cancer: A nationally representative cohort study

Background and aim: For a long time, aspirin has been recommended for the prevention of cardiovascular disease (CVD). However, results of long-term effects of aspirin use on the risk of CVD and all-cause death as well as cause-specific mortality are not consistent. This study aims to investigate the relationship between low- or high-dose preventive aspirin use and the risk of death from all-cause, CVD, and cancer among US adults aged 40 years and older. Methods: A prospective cohort study was conducted by utilizing four cycles of the National Health and Nutrition Examination Survey (NHANES) and linked 2019 mortality files. Cox proportional hazard models accounting for multiple covariates were used to calculate hazard ratio (HR) and 95% confidence interval (CI) for the associations between low- or high-dose aspirin use and risk of death. Results: A total of 10,854 individuals (5,364 men and 5,490 women) were enrolled in the study. During a median follow-up of 4.8 years, 924 death events including 294 CVD death and 223 cancer death were documented. We found no evidence that taking low-dose aspirin decreased the chance of dying from any cause (HR: 0.92, 95% CI: 0.79-1.06), CVD (HR: 1.03, 95% CI: 0.79-1.33), or cancer (HR: 0.80, 95% CI: 0.60-1.08). High-dose aspirin users had a higher risk of CVD death compared to participants who had never used aspirin (HR: 1.63, 95% CI: 1.11-2.41). Conclusion: Using low-dose aspirin has no effect on the risk of death from any causes, whereas taking high doses of aspirin increases the risk of CVD death.

Colorectal cancer chemoprevention: is aspirin still in the game?

Screening strategies have demonstrated their potential for decreasing the incidence and mortality of cancers, particularly that of colorectal cancer (CRC). Another strategy that has been developed to reduce CRC occurrence is the use of chemoprevention agents. Among them, aspirin is the most promising. Aspirin acts in colorectal tumourigenesis through several mechanisms, either directly in tumor cells or in their microenvironment, such as through its anti-inflammatory activity or its effect on the modulation of platelet function. Many retrospective studies, as well as follow-up of large cohorts from trials with primary cardiovascular end points, have shown that long-term treatment with daily low-dose aspirin decreases the incidence of adenomas and colorectal cancers. Therefore, aspirin is currently recommended by the United States Preventive Services Task Force (USPSTF) for primary prevention of CRC in all patients aged 50 to 59 with a 10-y risk of cardiovascular events greater than 10%. Furthermore, several studies have also reported that long-term aspirin treatment taking after CRC resection decreases recurrence risk and increases overall survival, especially in patients with PIK3CA-mutated tumors. This review summarizes current knowledge on the pathophysiological mechanisms of aspirin chemoprevention, discusses the primary clinical results on CRC prevention and highlights the potential biomarkers identified to predict aspirin efficacy.

Acetylsalicylic Acid-Primus Inter Pares in Pharmacology

Acetylsalicylic acid (ASA) is one of the first drugs to be obtained by synthesis while being the most used. It has experienced the longest lasting commercial success and is considered the most popular drug of the modern era. ASA, originally used as an anti-inflammatory medication, nowadays is predominantly used as an antiplatelet agent for prophylaxis in cardiac patients. Many studies show that the benefits of using ASA far outweigh the potential risk of side effects. With particular emphasis on the possibility of ASA repositioning for new therapies, extending the indications for use beyond the diseases from the spectrum of atherosclerotic diseases, such as cancer, requires shifting the benefit-risk ratio, although very good, even more towards safety. Interesting activities consisting not only of changing the formulation but also modifying the drug molecule seem to be an important goal of the 21st century. ASA has become a milestone in two important fields: pharmacy and medicine. For a pharmacist, ASA is a long-used drug for which individual indications are practically maintained. For a doctor, acetylsalicylic acid is primarily an antiplatelet drug that saves millions of lives of patients with coronary heart disease or after a stroke. These facts do not exempt us from improving therapeutic methods based on ASA, the main goal of which is to reduce the risk of side effects, as well as to extend effectiveness. Modified acetylsalicylic acid molecules already seem to be a promising therapeutic option.

Low-dose aspirin inhibits trophoblast cell apoptosis by activating the CREB/Bcl-2 pathway in pre-eclampsia

Excessive apoptosis of placental trophoblast cells is considered a major cause of pre-eclampsia (PE) pathogenesis. Phosphorylation of the widely expressed cAMP response element binding protein (CREB) regulates apoptosis and may be involved in PE incidence. Low-dose aspirin (LDA) is an effective approach for preventing PE with unclear mechanisms. Thus we examined whether LDA protects against PE by inhibiting trophoblast cell apoptosis through CREB. The effects of LDA on human PE placenta, PE model rat placenta, and hydrogen peroxide (H2O2)-induced HTR-8/SVneo cell apoptosis were analyzed. TUNEL assay, immunohistochemistry, Cell Counting Assay Kit-8 (CCK-8) assay, western blot, and flow cytometry assay were performed. In the placenta of human PE and rat PE models, the TUNEL index increased and was partially corrected with LDA pre-treatment. Meanwhile, decreased Bcl-2 and increased Bax expression were significantly reversed by LDA pre-treatment. In HTR-8/SVneo cells, H2O2 decreased cell viability, promoted apoptosis, reduced the Bcl-2/Bax ratio, aggravated loss of mitochondrial membrane potential (MMP), increased cytoplasmic cytochrome c release, and simultaneously activated caspase-9 and caspase-3. These effects were effectively restored by LDA pre-treatment in the cells. Moreover, LDA promoted CREB phosphorylation in trophoblast cells. CREB interference further promoted apoptosis, reduced the Bcl-2/Bax ratio, and increased MMP loss. CREB interference also reversed the inhibitory effect of LDA on H2O2-induced apoptosis in HTR-8/SVneo cells. Thus, LDA was shown to inhibit trophoblast cell mitochondrial apoptosis by activating the CREB/Bcl-2 pathway, providing novel evidence for the protective mechanism of LDA in PE.Abbreviations; PE: Pre-eclampsia; LDA: low-dose aspirin; CREB: cAMP response element binding protein; ROS: reactive oxygen species; H2O2: hydrogen peroxide; PBS: Phosphate-buffered saline; Bcl-2: B-cell lymphoma-2; MMP: Mitochondrial membrane potential; Cyt-c: CytochromeC.

Effect of body weight on bleeding events of aspirin in ischemic stroke or transient ischemic attack patients

WHAT IS KNOWN AND OBJECTIVES

Bleeding is the most common adverse reaction to aspirin and can lead to drug discontinuation or even be life-threatening in the secondary prevention of stroke or transient ischemic attack. The aim of this study was to evaluate risk factors for bleeding adverse reaction of aspirin in ischemic stroke or transient ischemic attack.

METHODS

This retrospective analysis included patients treated with aspirin (100 mg) as a secondary prevention for ischemic stroke or transient ischemic attack. The bleeding events that occurred during the first year were collected, including gastrointestinal, skin, nasal cavity, gum, and urinary tract bleeding events. Then, univariate and multivariate logistic regression analyses were used to identify independent factors associated with bleeding events of aspirin.

RESULTS AND DISCUSSION

A total of 578 patients were enrolled in this study, and 58 patients developed bleeding during the first year of secondary prevention. Body weight and combination with selective serotonin reuptake inhibitors were found to be significant risk factors for overall bleeding (p = 0.025 and 0.012). Body weight below 60 kg was a risk factor for overall bleeding and gastrointestinal bleeding events.

WHAT IS NEW AND CONCLUSION

Patients weighing less than 60 kg were at increased risk of bleeding with 100 mg aspirin for secondary prevention of cerebral infarction transient ischemic attack.

Modulation of Reactive Oxygen Species Homeostasis as a Pleiotropic Effect of Commonly Used Drugs

Age-associated diseases represent a growing burden for global health systems in our aging society. Consequently, we urgently need innovative strategies to counteract these pathological disturbances. Overwhelming generation of reactive oxygen species (ROS) is associated with age-related damage, leading to cellular dysfunction and, ultimately, diseases. However, low-dose ROS act as crucial signaling molecules and inducers of a vaccination-like response to boost antioxidant defense mechanisms, known as mitohormesis. Consequently, modulation of ROS homeostasis by nutrition, exercise, or pharmacological interventions is critical in aging. Numerous nutrients and approved drugs exhibit pleiotropic effects on ROS homeostasis. In the current review, we provide an overview of drugs affecting ROS generation and ROS detoxification and evaluate the potential of these effects to counteract the development and progression of age-related diseases. In case of inflammation-related dysfunctions, cardiovascular- and neurodegenerative diseases, it might be essential to strengthen antioxidant defense mechanisms in advance by low ROS level rises to boost the individual ROS defense mechanisms. In contrast, induction of overwhelming ROS production might be helpful to fight pathogens and kill cancer cells. While we outline the potential of ROS manipulation to counteract age-related dysfunction and diseases, we also raise the question about the proper intervention time and dosage.

Association between aspirin use during pregnancy and cardiovascular risk factors 2-7 years after delivery: The nuMoM2b Heart Health Study

OBJECTIVES

To evaluate the association between aspirin use during first pregnancy and later maternal cardiovascular risk.

STUDY DESIGN

In this secondary analysis of a prospective cohort, we included participants who carried their first pregnancy to 20 + weeks, had data regarding aspirin use, and attended a study visit 2-7 years following delivery. The exposure was aspirin use during the first pregnancy. We calculated aspirin use propensity scores from logistic regression models including baseline variables associated with aspirin use in pregnancy and cardiovascular risk. Outcomes of interest were incident cardiovascular-related diagnoses 2-7 years following delivery. Robust Poisson regression calculated the risk of outcomes by aspirin exposure, adjusting for the aspirin use propensity score.

MAIN OUTCOME MEASURES

The primary outcome was a composite of incident cardiovascular diagnoses at the time of the study visit: cardiovascular events, chronic hypertension, metabolic syndrome, prediabetes or type 2 diabetes, dyslipidemia, and chronic kidney disease.

RESULTS

Of 4,480 women included, 84 (1.9%) reported taking aspirin during their first pregnancy. 52.6% of participants in the aspirin-exposed group and 43.0% in the unexposed group had the primary outcome. After adjusting for the aspirin use propensity scores, aspirin use during the first pregnancy was not associated with any of the outcomes.

CONCLUSION

We did not detect an association between aspirin use during the first pregnancy and cardiovascular-related diagnoses 2-7 years later. Our study was only powered to detect a large difference in relative risk, so we cannot rule out a smaller difference that may be clinically meaningful.

Long-term low-dose acetylsalicylic use shows protective potential for the development of both vascular dementia and Alzheimer's disease in patients with coronary heart disease but not in other individuals from the general population: results from two large cohort studies

BACKGROUND

No population-based cohort study investigated a potential inverse association between long-term low-dose acetylsalicylic acid (ASA) use and all-cause dementia and its two most common sub-types Alzheimer's disease (AD) and vascular dementia (VD) so far.

METHODS

Cox regression models with inverse probability of treatment weighting to model the underlying cardiovascular risk were used to assess the associations of low-dose ASA use with all-cause dementia, AD, and VD incidence in community-dwelling older adults from the German ESTHER study (N = 5258) and the UK Biobank (N = 305,394). Inclusion criteria were age of 55 years or older and completed drug assessment. Meta-analyses of the individual participant data from the two prospective cohort studies were performed.

RESULTS

Four hundred seventy-six cases of all-cause dementia, 157 cases of AD, and 183 cases of VD were diagnosed over a median of 14.3 years of follow-up in ESTHER. In the UK Biobank, 5584 participants were diagnosed with all-cause dementia, 2029 with AD, and 1437 with VD over a median of 11.6 years. The meta-analysis of both cohorts revealed a weak reduction in hazards for all-cause dementia (hazard ratio (HR) [95% confidence interval (CI)]: 0.96 [0.93 to 0.99]). The strongest protective effect of low-dose ASA was observed in participants with coronary heart disease (CHD) in both cohorts, and a significant interaction was detected. In particular, in meta-analysis, a 31% reduction in hazard for AD, 69% for VD and 34% for all-cause dementia were observed (HR [95% CI]: 0.69 [0.59 to 0.80], 0.31 [0.27 to 0.35], 0.46 [0.42 to 0.50], respectively). Furthermore, compared to non-users, users of low-dose ASA for 10 years or longer (who likely use it because they have CHD or a related diagnosis putting them at an increased risk for cardiovascular events) demonstrated a strong protective effect on all dementia outcomes, especially for VD (HR [95% CI]: 0.48 [0.42 to 0.56]) whereas no protective associations were observed with shorter low-dose ASA use.

CONCLUSIONS

The protective potential of low-dose ASA for all-cause dementia, AD, and VD seems to strongly depend on pre-existing CHD and the willingness of patients to take it for a minimum of ten years.

Effect of taking aspirin before diagnosis on the prognosis of esophageal squamous cell carcinoma and analysis of prognostic factors

Objective

The 5-year survival rate of patients with esophageal squamous cell cancer (ESCC) is very low. However, long-term aspirin use has been suggested to have an adjuvant therapeutic effect. We therefore investigated the effect of long-term aspirin use before ESCC diagnosis on postoperative patient survival.

Methods

We carried out a retrospective cohort study of patients who underwent esophageal cancer resection in our hospital from 2008 to 2018. Patients were divided into an aspirin group (n = 79) and control group (n = 79), and were followed up until December 2019. We analyzed the clinicopathological and follow-up data of the patients during hospitalization, and the cyclooxygenase-2 (COX-2) protein expression levels by immunohistochemistry, and related these to postoperative survival.

Results

Patients who took aspirin had significantly lower survival rates than those who did not. COX-2-negative patients had better survival than patients with either low or high COX-2 expression levels. T stage was the only independent predictor of survival in patients who took aspirin.

Conclusions

Long-term regular use of aspirin before diagnosis had an adverse effect on postoperative survival in patients with ESCC. Different COX-2 protein expression levels were associated with significantly different postoperative survival rates, with COX-2-positive patients having the poorest survival.

Prediction of Low-Dose Aspirin-Induced Gastric Toxicity Using Nuclear Magnetic Resonance Spectroscopy-Based Pharmacometabolomics in Rats

BACKGROUND

Low-dose aspirin (LDA) is the backbone for secondary prevention of coronary artery disease, although limited by gastric toxicity. This study aimed to identify novel metabolites that could predict LDA-induced gastric toxicity using pharmacometabolomics.

METHODS

Pre-dosed urine samples were collected from male Sprague-Dawley rats. The rats were treated with either LDA (10 mg/kg) or 1% methylcellulose (10 mL/kg) per oral for 28 days. The rats' stomachs were examined for gastric toxicity using a stereomicroscope. The urine samples were analyzed using a proton nuclear magnetic resonance spectroscopy. Metabolites were systematically identified by exploring established databases and multivariate analyses to determine the spectral pattern of metabolites related to LDA-induced gastric toxicity.

RESULTS

Treatment with LDA resulted in gastric toxicity in 20/32 rats (62.5%). The orthogonal projections to latent structures discriminant analysis (OPLS-DA) model displayed a goodness-of-fit (R2Y) value of 0.947, suggesting near-perfect reproducibility and a goodness-of-prediction (Q2Y) of -0.185 with perfect sensitivity, specificity and accuracy (100%). Furthermore, the area under the receiver operating characteristic (AUROC) displayed was 1. The final OPLS-DA model had an R2Y value of 0.726 and Q2Y of 0.142 with sensitivity (100%), specificity (95.0%) and accuracy (96.9%). Citrate, hippurate, methylamine, trimethylamine N-oxide and alpha-keto-glutarate were identified as the possible metabolites implicated in the LDA-induced gastric toxicity.

CONCLUSION

The study identified metabolic signatures that correlated with the development of a low-dose Aspirin-induced gastric toxicity in rats. This pharmacometabolomic approach could further be validated to predict LDA-induced gastric toxicity in patients with coronary artery disease.

Sex-specific platelet activation through protease-activated receptor-1 in patients undergoing cardiac catheterization

BACKGROUND AND AIMS

Protease-activated receptor (PAR)-1-mediated platelet activation may vary according to sex and clinical situation. In order to investigate sex-specific platelet activation through PAR-1, we assessed platelet response to thrombin receptor-activating peptide (TRAP) in 562 patients undergoing cardiac catheterization without (Group 1A) and with (Group 1B) acute coronary syndrome (ACS). Subsequently, we sought to confirm our findings in 287 patients undergoing elective (Group 2A) or acute (Group 2B) percutaneous coronary intervention.

METHODS

TRAP-stimulated platelet surface expression of P-selectin and activated glycoprotein IIb/IIIa (GPIIb/IIIa) were measured by flow cytometry in Group 1. Light transmission aggregometry (LTA) and multiple electrode aggregometry (MEA) in response to TRAP were assessed in Group 2.

RESULTS

In Group 1A, platelet activation in response to TRAP was significantly higher in women compared to men (P-selectin: 511 MFI [443-597 MFI] vs. 471 MFI [393-552 MFI]; GPIIb/IIIa: 84 MFI [58-119 MFI] vs. 70 MFI [47-103 MFI]; both p ≤ 0.002). In contrast, in Group 1B, TRAP-stimulated P-selectin and activated GPIIb/IIIa were similar in men and women (both p ≥ 0.3). Likewise, TRAP-stimulated platelet aggregation was significantly higher in female patients in Group 2A (LTA: 66% [54-76%] vs. 51% [41-65%]; MEA: 78 AU [66-107 AU] vs. 62 AU [52-88 AU]; both p ≤ 0.02), whereas men and women in Group 2 B had similar platelet aggregation (p = 0.5). The occurrence of ischemic endpoints did not differ significantly between men and women in Group 1A and Group 1B.

CONCLUSIONS

Platelet PAR-1 signaling is more pronounced in women than in men without ACS. In ACS, however, PAR-1-mediated platelet activation is similar in male and female patients.

Efficacy and Safety of Aspirin for Primary Cardiovascular Risk Prevention in Younger and Older Age: An Updated Systematic Review and Meta-analysis of 178,310 Subjects from 21 Randomized Studies

AIMS

 The efficacy and safety of aspirin for primary cardiovascular disease (CVD) prevention is controversial. The aim of this study was to investigate the efficacy and safety of aspirin in subjects with no overt CVD, with a focus on age as a treatment modifier.

METHODS AND RESULTS

 Randomized trials comparing aspirin use versus no aspirin use or placebo were included. The primary efficacy outcome was all-cause death. The primary safety outcome was major bleeding. Secondary ischemic and bleeding outcomes were explored. Subgroup analyses were conducted to investigate the consistency of the effect sizes in studies including younger and older individuals, using a cut-off of 65 years. A total of 21 randomized trials including 173,810 individuals at a mean follow-up of 5.3 years were included. Compared with control, aspirin did not reduce significantly the risk of all-cause death (risk ratio: 0.96; 95% confidence interval: 0.92-1.00, p = 0.057). Major adverse cardiovascular events were significantly reduced by 11%, paralleled by significant reductions in myocardial infarction and transient ischemic attack. Major bleeding, intracranial hemorrhage, and gastrointestinal bleeding were significantly increased by aspirin. There was a significant age interaction for death (p for interaction = 0.007), with aspirin showing a statistically significant 7% relative benefit on all-cause death in studies including younger patients.

CONCLUSION

 The use of aspirin in subjects with no overt CVD was associated with a neutral effect on all-cause death and a modest lower risk of major cardiovascular events at the price of an increased risk in major bleeding. The benefit of aspirin might be more pronounced in younger individuals.

Aspirin at 120: Retiring, recombining, or repurposing?

During the past 20 years, we have witnessed the following trends in aspirin usage: (i) a "dropping" trend, characterized by the early discontinuation of low-dose aspirin from dual antiplatelet therapy or triple antithrombotic therapy (oral anticoagulation plus dual antiplatelet therapy in patients with atrial fibrillation) following an acute coronary syndrome or after percutaneous coronary intervention; (ii) a "combinatorial" trend, featuring the addition of a lower dose of a P2Y12 inhibitor or direct oral anticoagulant drug to low-dose aspirin for the long-term treatment of stable patients with atherosclerotic cardiovascular disease; and (iii) a "repurposing" trend, characterized by growing interest in the oncologic community to assess the chemopreventive effect of aspirin against certain types of cancers (particularly of the gastrointestinal tract), both as primary prevention and adjuvant therapy. The aim of this review is to present the mechanistic rationale underlying these trends, discuss the design and findings of trials testing novel treatments or new therapeutic applications of aspirin, and report on the ISTH Congress results on this topic.

Mechanisms of the antiangiogenic effects of aspirin in cancer

Aspirin is an old drug extracted from willow bark and is widely used for the prevention and treatment of cardiovascular diseases. Accumulating evidence has shown that aspirin use may significantly reduce the angiogenesis of cancer; however, the mechanism of the association between angiogenesis and aspirin is complex. Although COX-1 is widely known as a target of aspirin, several studies reveal other antiangiogenic targets of aspirin, such as angiotensin II, glucose transporter 1, heparanase, and matrix metalloproteinase. In addition, some data indicates that aspirin may produce antiangiogenic effects after acting in different cell types, such as endothelial cells, platelets, pericytes, and macrophages. In this review, we concentrate on research regarding the antiangiogenic effects of aspirin in cancer, and we discuss the molecular mechanisms of aspirin and its metabolites. Moreover, we discuss some mechanisms through which aspirin treatment may normalize existing blood vessels, including preventing the disintegration of endothelial adheres junctions and the recruitment of pericytes. We also address the antiangiogenic effects and the underlying mechanisms of aspirin derivatives, which are aimed at improving safety and efficacy.

Aspirin Use on Incident Dementia and Mild Cognitive Decline: A Systematic Review and Meta-Analysis

Background: More people with cognitive dysfunction and dementia also fall into the category of high vascular risk, for which aspirin is one of the most frequently used drugs. However, previous studies reporting that aspirin buffers against mild cognitive decline (MCI) and dementia remain controversial. We thus conducted an updated systematic review and meta-analysis to evaluate the association of aspirin use with the risk of MCI and dementia in older adults.

Methods: Data sources from PubMed, Embase, Web of Science, and the Cochrane Database for randomized controlled trails (RCTs) and cohort studies (published between January 1, 2000 and April 11, 2020). Relative risks (RRs) and 95% confidence intervals (95% CIs) were used to pool data on the occurrence of dementia and MCI with random-effects models.

Results: Of 3,193 identified articles, 15 studies (12 cohort studies and three RCTs) were eligible and were included in our analysis, which involved a total of 100,909 participants without cognitive dysfunctions or dementia at baseline. In pooled cohort studies, aspirin use did not reduce the incidence of MCI and dementia (the pooled RR = 0.97; 95% CI = 0.85–1.11; Ifor heterogeneity2 = 65%) compared with non-users. However, low-dose aspirin (75–100 mg/day) was associated with a decreased likelihood of developing dementia or MCI (the pooled RR = 0.75; 95% CI = 0.63–0.9; Ifor heterogeneity2 = 50.5%). This association existed in studies including all-cause dementia (the pooled RR = 0.82; 95% CI = 0.71–0.96) and Alzheimer's disease (AD) (the pooled RR = 0.54; 95% CI = 0.33–0.89), but not in MCI (the pooled RR = 0.58; 95% CI = 0.31–1.08). In RCTs, low-dose aspirin use was not significantly associated with less prevalence of dementia or MCI (RR = 0.94; 95% CI = 0.84–1.05; Ifor heterogeneity2 = 0.0%).

Conclusions: In cohort studies, we found that low-dose aspirin use had a higher likelihood of reducing the incidence of dementia, which was not supported by RCTs. The evidence was insufficient to fully evaluate the effect of aspirin on cognitive function and dementia. Well-designed studies and innovative approaches are therefore needed to clarify whether the use of aspirin improves cognitive function and reduces the risk of dementia.

Association between renal function and platelet reactivity during aspirin therapy in elderly patients with atherosclerotic cardiovascular disease

Background

Aspirin is the key treatment in the secondary prevention of atherosclerotic cardiovascular disease. High on-treatment platelet reactivity (HTPR) to aspirin has been reported to partially account for the enhanced risk of thrombotic events. In particular, HTPR has been described more frequently among elderly patients. The aim of this study was to identify the clinical and biological factors associated with HTPR in a real-life elderly population.

Methods

In this retrospective study, elderly patients with atherosclerotic cardiovascular disease on regular aspirin treatment were enrolled. Cardiovascular risk factors, routine biological parameters, comorbidities, and concomitant medications were recorded. The upper quartile of the platelet aggregation rate, determined by light transmission aggregometry with arachidonic acid, was defined as the HTPR group.

Results

A total of 304 patients were included (mean age 77 ± 8 years, 76% men). Patients in the HTPR group were older than the patients in the non-HTPR group (mean age: 79 ± 7 vs. 76 ± 8 years, p = 0.008). Patients with moderately decreased estimated glomerular filtration rate (eGFR) had a higher frequency of HTPR than patients with slightly decreased eGFR or normal eGFR (35.8, 22.5, 12.2%, respectively, p < 0.05). In multivariate analysis, an independent risk factor for HTPR was the eGFR (OR: 0.984, 95% CI: 0.980–0.988, p < 0.001).

Conclusions

Advanced age and decreased eGFR are correlated with poor pharmacodynamic response to aspirin.

Preventing the development of severe COVID-19 by modifying immunothrombosis

BACKGROUND

COVID-19-associated acute respiratory distress syndrome (ARDS) is associated with significant morbidity and high levels of mortality. This paper describes the processes involved in the pathophysiology of COVID-19 from the initial infection and subsequent destruction of type II alveolar epithelial cells by SARS-CoV-2 and culminating in the development of ARDS.

MAIN BODY

The activation of alveolar cells and alveolar macrophages leads to the release of large quantities of proinflammatory cytokines and chemokines and their translocation into the pulmonary vasculature. The presence of these inflammatory mediators in the vascular compartment leads to the activation of vascular endothelial cells platelets and neutrophils and the subsequent formation of platelet neutrophil complexes. These complexes in concert with activated endothelial cells interact to create a state of immunothrombosis. The consequence of immunothrombosis include hypercoagulation, accelerating inflammation, fibrin deposition, migration of neutrophil extracellular traps (NETs) producing neutrophils into the alveolar apace, activation of the NLRP3 inflammazome, increased alveolar macrophage destruction and massive tissue damage by pyroptosis and necroptosis Therapeutic combinations aimed at ameliorating immunothrombosis and preventing the development of severe COVID-19 are discussed in detail.

Genetic variation at the coronary artery disease risk locus GUCY1A3 modifies cardiovascular disease prevention effects of aspirin

AIMS

Efficacy of aspirin in primary prevention of cardiovascular disease (CVD) may be influenced by a common allele in guanylate cyclase GUCY1A3, which has been shown to modify platelet function and increase CVD risk.

METHODS AND RESULTS

We investigated whether homozygotes of the GUCY1A3 rs7692387 risk (G) allele benefited from aspirin in two long-term, randomized placebo-controlled trials of aspirin in primary CVD prevention: the Women's Genome Health Study (WGHS, N = 23 294) and a myocardial infarction (MI, N = 550) and stroke (N = 382) case-control set from the Physician's Health Study (PHS, N = 22 071). Bleeding risk was evaluated in the WGHS. In the placebo group of the WGHS, the GUCY1A3 risk (G) allele was confirmed to increase CVD risk [hazard ratio 1.38; 95% confidence interval (CI) 1.08-1.78; P = 0.01]. Random-effects meta-analysis of the WGHS and PHS revealed that aspirin reduced CVD events among risk allele homozygotes [G/G: odds ratio (OR) 0.79; 95% CI 0.65-0.97; P = 0.03] but increased CVD events among non-risk allele carriers (e.g. G/A: OR 1.39; 95% CI 1.03-1.87; P = 0.03) thus implying an interaction between genotype stratum and aspirin intake (Pinteraction = 0.01). Bleeding associated with aspirin increased in all genotype groups, with higher risks in heterozygotes.

CONCLUSION

In two randomized placebo-controlled trials in the setting of primary prevention, aspirin reduced the incidence of CVD events in individuals homozygous for the GUCY1A3 risk (G) allele, whereas heterozygote individuals had more events when taking aspirin.

A potential role for aspirin in the prevention and treatment of cholangiocarcinoma

Cholangiocarcinoma is the second most common primary hepatic cancer, with a rising incidence worldwide. Owing to late diagnosis and limited treatment options, the prognosis for cholangiocarcinoma remains dismal, compelling a search for new treatments. As aspirin exhibits a well-supported chemopreventive effect on common cancers, researchers have proposed using aspirin as a potential preventive and adjuvant agent for cholangiocarcinoma. In the present review of the literature, we provide a background on cholangiocarcinoma and potential mechanisms of action underlying the anticancer effect of aspirin. Although the exact mode of action remains unclear, multiple downstream effects of aspirin may interfere with cholangiocarcinogenesis, tumour growth and metastasis-including inhibiting the COX-2 pathway, preventing platelet aggregation and modulating certain proteins and signalling. This review also summarises evidence to support the chemopreventive effects of aspirin on common cancers, particularly colorectal cancer and discusses studies that report a positive outcome of aspirin in cholangiocarcinoma. Regular use of aspirin is associated with a reduced incidence of colorectal cancers as well as cholangiocarcinomas, and improved survival. Aspirin thus appears to play a role in the primary prevention and treatment of cholangiocarcinoma. However, further studies are needed to confirm these benefits and to establish a cause-and-effect relationship.

Aspirin for primary prevention of ST segment elevation myocardial infarction in persons with diabetes and multiple risk factors

BACKGROUND

Controversy exists as to whether low-dose aspirin use may give benefit in primary prevention of cardiovascular (CV) events. We hypothesized that the benefits of aspirin are underevaluated.

METHODS

We investigated 12,123 Caucasian patients presenting to hospital with acute coronary syndromes as first manifestation of CV disease from 2010 to 2019 in the ISACS-TC multicenter registry (ClinicalTrials.gov, NCT01218776). Individual risk of ST segment elevation myocardial infarction (STEMI) and its association with 30-day mortality was quantified using inverse probability of treatment weighting models matching for concomitant medications. Estimates were compared by test of interaction on the log scale.

FINDINGS

The risk of STEMI was lower in the aspirin users (absolute reduction: 6·8%; OR: 0·73; 95%CI: 0·65-0·82) regardless of sex (p for interaction=0·1962) or age (p for interaction=0·1209). Benefits of aspirin were seen in patients with hypertension, hypercholesterolemia, and in smokers. In contrast, aspirin failed to demonstrate a significant risk reduction in STEMI among diabetic patients (OR:1·10;95%CI:0·89-1·35) with a significant interaction (p: <0·0001) when compared with controls (OR:0·64,95%CI:0·56-0·73). Stratification of diabetes in risk categories revealed benefits (p interaction=0·0864) only in patients with concomitant hypertension and hypercholesterolemia (OR:0·87, 95% CI:0·65-1·15), but not in smokers. STEMI was strongly related to 30-day mortality (OR:1·93; 95%CI:1·59-2·35).

INTERPRETATION

Low-dose aspirin reduces the risk of STEMI as initial manifestation of CV disease with potential benefit in mortality. Patients with diabetes derive substantial benefit from aspirin only in the presence of multiple risk factors. In the era of precision medicine, a more tailored strategy is required.

FUNDING

None.

Novel Approaches to Fine-Tune Therapeutic Targeting of Platelets in Atherosclerosis: A Critical Appraisal

The pathogenesis of atherosclerotic vascular disease is driven by a multitude of risk factors intertwining metabolic and inflammatory pathways. Increasing knowledge about platelet biology sheds light on how platelets take part in these processes from early to later stages of plaque development. Recent insights from experimental studies and mouse models substantiate platelets as initiators and amplifiers in atherogenic leukocyte recruitment. These studies are complemented by results from genetics studies shedding light on novel molecular mechanisms which provide an interesting prospect as novel targets. For instance, experimental studies provide further details how platelet-decorated von Willebrand factor tethered to activated endothelial cells plays a role in atherogenic monocyte recruitment. Novel aspects of platelets as atherogenic inductors of neutrophil extracellular traps and particularities in signaling pathways such as cyclic guanosine monophosphate and the inhibitory adaptor molecule SHB23/LNK associating platelets with atherogenesis are shared. In summary, it was our intention to balance insights from recent experimental data that support a plausible role for platelets in atherogenesis against a paucity of clinical evidence needed to validate this concept in humans.

Aspirin and the risk of colorectal and other digestive tract cancers: an updated meta-analysis through 2019

BACKGROUND

Aspirin has been associated with a reduced risk of colorectal cancer, and possibly of a few other digestive tract cancers. The quantification of risk reduction and the optimal dose and duration of aspirin use for the prevention of colorectal and other digestive tract cancers remains unclear.

METHODS

To provide an up-to-date quantification of this association, we conducted a systematic review and meta-analysis of all observational studies on aspirin and cancers of the digestive tract sites published through March 2019. We estimated the pooled relative risk (RR) of cancer for regular aspirin use versus non-use using random-effects models, and, whenever data were available, we investigated the dose- and duration-risk relations.

RESULTS

Regular aspirin use is associated with a reduced risk of colorectal cancer [RR = 0.73, 95% confidence interval (CI) = 0.69-0.78, 45 studies], squamous-cell esophageal cancer (RR = 0.67, 95% CI = 0.57-0.79, 13 studies), adenocarcinoma of the esophagus and gastric cardia (RR = 0.61, 95% CI = 0.49-0.77, 10 studies), stomach cancer (RR = 0.64, 95% CI = 0.51-0.82, 14 studies), hepato-biliary tract cancer (RR = 0.62, 95% CI = 0.44-0.86, five studies), and pancreatic cancer (RR = 0.78, 95% CI = 0.68-0.89, 15 studies), but not of head and neck cancer (RR = 0.94, 95% CI = 0.76-1.16, 10 studies). The associations are somewhat stronger in case-control than in cohort and nested case-control studies and are characterized by some between-study heterogeneity. Risk estimates are consistent across sex, geographical areas, and other selected covariates. For colorectal cancer, an aspirin dose between 75 and 100 mg/day conveys a risk reduction of 10%, and a dose of 325 mg/day of 35%. For all neoplasms, except head and neck cancer, inverse duration-risk relations with aspirin use are found.

CONCLUSION

The present comprehensive meta-analysis supports and further quantifies the inverse association between regular aspirin use and the risk of colorectal and other digestive tract cancers, including some rare ones. The favorable effect of aspirin increases with longer duration of use, and, for colorectal cancer, with increasing dose.

Platelet Function Test Use for Patients with Coronary Artery Disease in the Early 2020s

In the field of antithrombotics, precision medicine is of particular interest, as it may lower the incidence of potentially life-threatening side effects. Indeed, antiplatelet drugs such as P2Y₁₂ inhibitors are one of the most common causes of emergency admissions for drug-related adverse events. The last ten years have seen a continuous debate on whether platelet function tests (PFTs) should be used to tailor antiplatelet drugs to cardiovascular patients. Large-scale randomized studies investigating the escalation of antiplatelet therapies according to the results of PFTs were mostly negative. Potent P2Y₁₂ inhibitors are recommended as a first-line treatment in acute coronary syndrome patients, bringing the bleeding risk at the forefront. De-escalation from prasugrel or ticagrelor to clopidogrel is now considered, with or without the use of a PFT. This review covers recent advances in escalation and de-escalation strategies based on PFTs in various clinical settings. It also describes the main features of the most popular platelet function tests as well as the potential added value of genetic testing. Finally, we detail practical suggestions on how PFTs could be used in clinical practice.

The effect of low-dose aspirin on colorectal cancer prevention and gastrointestinal bleeding according to bodyweight and body mass index: Analysis of UK primary care data

BACKGROUND

Meta-analysis of trial data suggests that in primary cardiovascular disease (CVD) prevention bodyweight modifies low-dose aspirin's effects on colorectal cancer (CRC) and major bleeding risk. We sought to investigate whether these effects are seen in patients with or without CVD in routine clinical practice by undertaking sub-analyses of data from two cohort studies with nested-case-control analyses.

METHODS

We followed ~200,000 new users of low-dose aspirin (75-300 mg/day) and a matched cohort of non-users to identify incident cases of CRC/upper gastrointestinal bleeding (UGIB). Adjusted relative risks (RRs) with 95% confidence intervals (CIs) were calculated for current vs. non-use of low-dose aspirin using logistic regression stratified by bodyweight/body mass index (BMI) strata.

RESULTS

RRs (95% CIs) for CRC by bodyweight were: 0.60 (0.50-0.72) for ≤70 kg, 0.68 (0.60-0.76) for >70 kg; and by BMI were 0.60 (0.52-0.68) for ≤28 kg/m², 0.76 (0.64-0.89) for >28 kg/m². For UGIB, estimates were: 1.49 (1.28-1.74) for ≤90 kg, 1.78 (1.29-2.45) for >90 kg/m², 1.44 (1.21-1.72) for ≤28 kg/m², 1.72 (1.38-2.16) for >28 kg/m². Results were similar in the primary CVD prevention population.

CONCLUSION

Our findings suggest that the effects of low-dose aspirin in reducing CRC risk and increasing UGIB risk are not modified by bodyweight/BMI.

Aspirin metabolites 2,3‑DHBA and 2,5‑DHBA inhibit cancer cell growth: Implications in colorectal cancer prevention

Although compelling evidence exists on the ability of aspirin to treat colorectal cancer (CRC), and numerous theories and targets have been proposed, a consensus has not been reached regarding its mechanism of action. In this regard, a relatively unexplored area is the role played by aspirin metabolites 2,3-dihydroxybenzoic acid (2,3-DHBA) and 2,5-dihydroxybenzoic acid (2,5-DHBA) in its chemopreventive actions. In a previous study, we demonstrated that 2,3-DHBA and 2,5-DHBA inhibited CDK1 enzyme activity in vitro. The aim of the present study was to understand the effect of these metabolites on the enzyme activity of all CDKs involved in cell cycle regulation (CDKs 1, 2, 4 and 6) as well as their effect on clonal formation in three different cancer cell lines. Additionally, in silico studies were performed to determine the potential sites of interactions of 2,3-DHBA and 2,5-DHBA with CDKs. We demonstrated that 2,3-DHBA and 2,5-DHBA inhibits CDK-1 enzyme activity beginning at 500 µM, while CDK2 and CDK4 activity was inhibited only at higher concentrations (>750 µM). 2,3-DHBA inhibited CDK6 enzyme activity from 250 µM, while 2,5-DHBA inhibited its activity >750 µM. Colony formation assays showed that 2,5-DHBA was highly effective in inhibiting clonal formation in HCT-116 and HT-29 CRC cell lines (250–500 µM), and in the MDA-MB-231 breast cancer cell line (~100 µM). In contrast 2,3-DHBA was effective only in MDA-MB-231 cells (~500 µM). Both aspirin and salicylic acid failed to inhibit all four CDKs and colony formation. Based on the present results, it is suggested that 2,3-DHBA and 2,5-DHBA may contribute to the chemopreventive properties of aspirin, possibly through the inhibition of CDKs. The present data and the proposed mechanisms should open new areas for future investigations.

Role of aspirin in primary prevention of cardiovascular disease

The benefits of aspirin therapy for the secondary prevention of cardiovascular disease clearly outweigh the risks of bleeding, and low-dose aspirin is uniformly recommended in this setting. However, no clear consensus exists about whether, and if so in whom, aspirin therapy is appropriate for the primary prevention of cardiovascular disease. Three trials of low-dose aspirin versus placebo in three populations at increased risk of myocardial infarction or ischaemic stroke in the absence of established cardiovascular disease were reported in 2018. The ASPREE trial in elderly people was terminated early for futility because aspirin had no effect on disability-free survival but significantly increased the risk of major haemorrhage and, unexpectedly, all-cause mortality. In the ASCEND trial in patients with diabetes mellitus and no evidence of vascular disease, aspirin significantly reduced serious vascular events but increased major bleeding. In the ARRIVE trial in people with multiple risk factors for cardiovascular disease, aspirin had no effect on major cardiovascular events but increased gastrointestinal bleeding. The aim of this Review is to place these new results in the context of previous evidence on aspirin for the primary prevention of cardiovascular disease and to appraise whether the new evidence is likely to enable the more targeted use of aspirin in particular individuals for whom the net benefit is both clinically worthwhile and statistically definite.

The dilemma of aspirin resistance in obese patients

Aspirin resistance (AR) commonly refers to the concept of reduced aspirin efficacy in preventing cardiovascular disease and platelet inhibition. Obesity increases the risk of heart disease three- to four-fold and has been associated with AR. Aspirin is used as a tool for both primary and secondary prevention, but recent studies suggest that its lack of efficacy for primary prevention is partly attributable to obesity. Several mechanisms have been described that contribute to AR in obese patients using pharmacokinetics and pharmacodynamics. AR may be attenuated through weight loss, alternative dosing regimens, and different drug formulations. With the global rise of obesity, it is imperative to find preventive therapies that adequately address atherosclerotic cardiovascular disease (ASCVD) risk in this population.

Aspirin and its pleiotropic application

Aspirin (acetylsalicylic acid), the oldest synthetic drug, was originally used as an anti-inflammatory medication. Being an irreversible inhibitor of COX (prostaglandin-endoperoxide synthase) enzymes that produce precursors for prostaglandins and thromboxanes, it has gradually found several other applications. Sometimes these applications are unrelated to its original purpose for example its use as an anticoagulant. Applications such as these have opened opportunities for new treatments. In this case, it has been tested in patients with cardiovascular disease to reduce the risk of myocardial infarct. Its function as an anticoagulant has also been explored in the prophylaxis and treatment of pre-eclampsia, where due to its anti-inflammatory properties, aspirin intake may be used to reduce the risk of colorectal cancer. It is important to always consider both the risks and benefits of aspirin's application. This is especially important for proposed use in the prevention and treatment of neurologic ailments like Alzheimer's disease, or in the prophylaxis of myocardial infarct. In such cases, the decision if aspirin should be applied, and at what dose may be guided by specific molecular markers. In this revived paper, the pleiotropic application of aspirin is summarized.

Aspirin alleviates endothelial gap junction dysfunction through inhibition of NLRP3 inflammasome activation in LPS-induced vascular injury

The loss of endothelial connective integrity and endothelial barrier dysfunction can lead to increased vascular injury, which is related to the activation of endothelial inflammasomes. There are evidences that low concentrations of aspirin can effectively prevent cardiovascular diseases. We hypothesized that low-dose aspirin could ameliorate endothelial injury by inhibiting the activation of NLRP3 inflammasomes and ultimately prevent cardiovascular diseases. Microvascular endothelial cells were stimulated by lipopolysaccharide (2 μg/mL) and administrated by 0.1–2 mmol/L aspirin. The wild type mice were stimulated with LPS (100 μg/kg/day), and 1 h later treated with aspirin (12.5, 62.5, or 125 mg/kg/day) and dexamethasone (0.0182 mg/kg/day) for 7 days. Plasma and heart were harvested for measurement of ELISA and immunofluorescence analyses. We found that aspirin could inhibit NLRP3 inflammasome formation and activation in vitro in dose-dependent manner and has correlation between the NLRP3 inflammasome and the ROS/TXNIP pathway. We also found that low-concentration aspirin could inhibit the formation and activation of NLRP3 inflammasome and restore the expression of the endothelial tight junction protein zonula occludens-1/2 (ZO1/2). We assume that aspirin can ameliorate the endothelial layer dysfunction by suppressing the activation of NLRP3 inflammasome.

Targeting Early Atherosclerosis: A Focus on Oxidative Stress and Inflammation

Atherosclerosis is a chronic vascular inflammatory disease associated to oxidative stress and endothelial dysfunction. Oxidation of low-density lipoprotein (LDL) cholesterol is one of the key factors for the development of atherosclerosis. Nonoxidized LDL have a low affinity for macrophages, so they are not themselves a risk factor. However, lowering LDL levels is a common clinical practice to reduce oxidation and the risk of major events in patients with cardiovascular diseases (CVD). Atherosclerosis starts with dysfunctional changes in the endothelium induced by disturbed shear stress which can lead to endothelial and platelet activation, adhesion of monocytes on the activated endothelium, and differentiation into proinflammatory macrophages, which increase the uptake of oxidized LDL (oxLDL) and turn into foam cells, exacerbating the inflammatory signalling. The atherosclerotic process is accelerated by a myriad of factors, such as the release of inflammatory chemokines and cytokines, the generation of reactive oxygen species (ROS), growth factors, and the proliferation of vascular smooth muscle cells. Inflammation and immunity are key factors for the development and complications of atherosclerosis, and therefore, the whole atherosclerotic process is a target for diagnosis and treatment. In this review, we focus on early stages of the disease and we address both biomarkers and therapeutic approaches currently available and under research.

Platelets and extracellular vesicles in cancer: diagnostic and therapeutic implications

Several pieces of evidence support the role of activated platelets in the development of the chronic inflammation-related diseases, such as atherothrombosis and cancer, mainly via the release of soluble factors and microparticles (MPs). Platelets and MPs contain a repertoire of proteins and genetic material (i.e., mRNAs and microRNAs) which may be influenced by the clinical condition of the individuals. In fact, platelets are capable of up-taking proteins and genetic material during their lifespan. Moreover, the content of platelet-derived MPs can be delivered to other cells, including stromal, immune, epithelial, and cancer cells, to change their phenotype and functions, thus contributing to cancer promotion and its metastasization. Platelets and MPs can play an indirect role in the metastatic process by helping malignant cells to escape from immunological surveillance. Furthermore, platelets and their derived MPs represent a potential source for blood biomarker development in oncology. This review provides an updated overview of the roles played by platelets and MPs in cancer and metastasis formation. The possible analysis of platelet and MP molecular signatures for the detection of cancer and monitoring of anticancer treatments is discussed. Finally, the potential use of MPs as vectors for drug delivery systems to cancer cells is put forward.

Association of the coronary artery disease risk gene GUCY1A3 with ischaemic events after coronary intervention

Aim

A common genetic variant at the GUCY1A3 coronary artery disease locus has been shown to influence platelet aggregation. The risk of ischaemic events including stent thrombosis varies with the efficacy of aspirin to inhibit platelet reactivity. This study sought to investigate whether homozygous GUCY1A3 (rs7692387) risk allele carriers display higher on-aspirin platelet reactivity and risk of ischaemic events early after coronary intervention.

Methods and results

The association of GUCY1A3 genotype and on-aspirin platelet reactivity was analysed in the genetics substudy of the ISAR-ASPI registry (n = 1678) using impedance aggregometry. The clinical outcome cardiovascular death or stent thrombosis within 30 days after stenting was investigated in a meta-analysis of substudies of the ISAR-ASPI registry, the PLATO trial (n = 3236), and the Utrecht Coronary Biobank (n = 1003) comprising a total 5917 patients. Homozygous GUCY1A3 risk allele carriers (GG) displayed increased on-aspirin platelet reactivity compared with non-risk allele (AA/AG) carriers [150 (interquartile range 91–209) vs. 134 (85–194) AU⋅min, P < 0.01]. More homozygous risk allele carriers, compared with non-risk allele carriers, were assigned to the high-risk group for ischaemic events (>203 AU⋅min; 29.5 vs. 24.2%, P = 0.02). Homozygous risk allele carriers were also at higher risk for cardiovascular death or stent thrombosis (hazard ratio 1.70, 95% confidence interval 1.08–2.68; P = 0.02). Bleeding risk was not altered.

Conclusion

We conclude that homozygous GUCY1A3 risk allele carriers are at increased risk of cardiovascular death or stent thrombosis within 30 days after coronary stenting, likely due to higher on-aspirin platelet reactivity. Whether GUCY1A3 genotype helps to tailor antiplatelet treatment remains to be investigated.