Honigberg, Michael C

Platelets are central to hemostasis and thrombosis. Excessive platelet activation contributes to arterial thrombotic events, including myocardial infarction, ischemic stroke, and complications of peripheral artery disease, whereas excessive platelet inhibition increases bleeding risk. Antiplatelet therapy remains a cornerstone of secondary prevention in atherosclerotic and thrombotic cardiovascular diseases, yet current treatment paradigms do not fully account for biological heterogeneity in platelet function, including differences related to sex, age, hormonal status, and disease context. This state-of-the-art review examines current antiplatelet strategies, fundamental mechanisms of signal transduction, clinical indications, and limitations of preclinical and clinical studies, with a focus on sex-specific considerations and opportunities for personalized antiplatelet therapy. Aspirin and P2Y 12 receptor antagonists are widely used for secondary prevention. However, women have been underrepresented in many pivotal clinical trials, limiting the precision of sex-specific estimates of efficacy and bleeding risk. In parallel, commonly used preclinical models often fail to recapitulate the physiological conditions in which platelets interact with the vasculature, leukocytes, and soluble factors. Emerging therapeutic approaches seek to refine platelet inhibition by targeting pathways that reduce thrombotic risk while preserving hemostasis. Advancing antiplatelet therapy will require integration of mechanistic platelet biology with diverse clinical trial populations, standardized platelet phenotyping, and disease-specific approaches that account for how platelet function is altered across health and vascular disease.

Abstract Clonal hematopoiesis (CH) is characterized by expanding blood cell clones carrying somatic mutations in healthy aged individuals and is associated with various age-related diseases and all-cause mortality. While CH mutations affect diverse genes associated with myeloid malignancies, their mechanisms of expansion and disease associations remain poorly understood. We investigate the relationship between clonal fitness and clinical outcomes by integrating data from three longitudinal aging cohorts (n=713, observations=2,341). We demonstrate pathway-specific fitness advantage and clonal composition influence clonal dynamics. Further, the timing of mutation acquisition is necessary to determine the extent of clonal expansion reached during the host individual’s lifetime. We introduce MACS120, a metric combining mutation context, timing, and variant fitness to predict future clonal growth, outperforming traditional variant allele frequency measurements in predicting clinical outcomes. Our unified analytical framework enables standardized clonal dynamics inference across cohorts, advancing our ability to predict and potentially intervene in CH-related pathologies.

Peripartum cardiomyopathy (PPCM) is an idiopathic form of pregnancy-induced heart failure associated with preeclampsia. Circulating factors in late pregnancy are thought to contribute to both diseases, suggesting a common underlying pathophysiological process. However, what drives this process remains unclear. Using serum proteomics, we identified the senescence-associated secretory phenotype (SASP), a marker of cellular senescence associated with biological aging, as the most highly up-regulated pathway in young women with PPCM or preeclampsia. Placentas from women with preeclampsia displayed multiple markers of amplified senescence and tissue aging, as well as overall increased gene expression of 28 circulating proteins that contributed to SASP pathway enrichment in serum samples from patients with preeclampsia or PPCM. The most highly expressed placental SASP factor, activin A, was associated with cardiac dysfunction or heart failure severity in women with preeclampsia or PPCM. In a murine model of PPCM induced by cardiomyocyte-specific deletion of the gene encoding peroxisome proliferator–activated receptor γ coactivator-1α, inhibiting activin A signaling in the early postpartum period with a monoclonal antibody to the activin type II receptor improved heart function. In addition, attenuating placental senescence with the senolytic compound fisetin in late pregnancy improved cardiac function in these animals. These findings link senescence biology to cardiac dysfunction in pregnancy and help to elucidate the pathogenesis underlying cardiovascular diseases of pregnancy.

BACKGROUND: Premature menopause is a risk factor for accelerated cardiovascular aging, but underlying mechanisms remain incompletely understood. This study investigated the role of leukocyte telomere length (LTL), a marker of cellular aging and genomic instability, in the association of premature menopause with cardiovascular disease. METHODS: Participants from the UK Biobank and Women’s Health Initiative with complete reproductive history and LTL measurements were included. Primary analyses tested the association between age at menopause and LTL using multivariable-adjusted linear regression. Secondary analyses stratified women by history of gynecologic surgery. Mendelian randomization was used to infer causal relationships between LTL and age at natural menopause. Multivariable-adjusted Cox regression and mediation analyses tested the joint associations of premature menopause and LTL with incident coronary artery disease. RESULTS: This study included 130 254 postmenopausal women (UK Biobank: n=122 224; Women’s Health Initiative: n=8030), of whom 4809 (3.7%) had experienced menopause before age 40. Earlier menopause was associated with shorter LTL (meta-analyzed ß=−0.02 SD/5 years of earlier menopause [95% CI, −0.02 to −0.01]; P =7.2×10 -12 ). This association was stronger and significant in both cohorts for women with natural/spontaneous menopause (meta-analyzed ß=−0.04 SD/5 years of earlier menopause [95% CI, −0.04 to −0.03]; P <2.2×10 -16 ) and was independent of hormone therapy use. Mendelian randomization supported a causal association of shorter genetically predicted LTL with earlier age at natural menopause. LTL and age at menopause were independently associated with incident coronary artery disease, and mediation analyses indicated small but significant mediation effects of LTL in the association of menopausal age with coronary artery disease. CONCLUSIONS: Earlier age at menopause is associated with shorter LTL, especially among women with natural menopause. Accelerated telomere shortening may contribute to the heightened cardiovascular risk associated with premature menopause.

Human genetic studies support an inverse causal relationship between leukocyte telomere length (LTL) and coronary artery disease (CAD), but directionally mixed effects for LTL and diverse malignancies. Clonal hematopoiesis of indeterminate potential (CHIP), characterized by expansion of hematopoietic cells bearing leukemogenic mutations, predisposes both hematologic malignancy and CAD. TERT (which encodes telomerase reverse transcriptase) is the most significantly associated germline locus for CHIP in genome-wide association studies. Here, we investigated the relationship between CHIP, LTL, and CAD in the Trans-Omics for Precision Medicine (TOPMed) program ( n = 63,302) and UK Biobank ( n = 47,080). Bidirectional Mendelian randomization studies were consistent with longer genetically imputed LTL increasing propensity to develop CHIP, but CHIP then, in turn, hastens to shorten measured LTL (mLTL). We also demonstrated evidence of modest mediation between CHIP and CAD by mLTL. Our data promote an understanding of potential causal relationships across CHIP and LTL toward prevention of CAD.

Beyond conventional risk factors for cardiovascular disease, women face an additional burden of sex-specific risk factors. Key stages of a woman’s reproductive history may influence or reveal short- and long-term cardiometabolic and cardiovascular trajectories. Early and late menarche, polycystic ovary syndrome, infertility, adverse pregnancy outcomes (eg, hypertensive disorders of pregnancy, gestational diabetes, preterm delivery, and intrauterine growth restriction), and absence of breastfeeding are all associated with increased future cardiovascular disease risk. The menopause transition additionally represents a period of accelerated cardiovascular disease risk, with timing (eg, premature menopause), mechanism, and symptoms of menopause, as well as treatment of menopause symptoms, each contributing to this risk. Differences in conventional cardiovascular disease risk factors appear to explain some, but not all, of the observed associations between reproductive history and later-life cardiovascular disease; further research is needed to elucidate hormonal effects and unique sex-specific disease mechanisms. A history of reproductive risk factors represents an opportunity for comprehensive risk factor screening, refinement of cardiovascular disease risk assessment, and implementation of primordial and primary prevention to optimize long-term cardiometabolic health in women.