Clonal hematopoiesis associated with epigenetic aging and clinical outcomes

Clonal Hematopoiesis of Indeterminate Potential and Long-term Outcomes in Heart Transplantation

BACKGROUND

Clonal hematopoiesis of indeterminate potential (CHIP) mutations, an aging trait, has been associated with progression of cardiovascular disease and development of malignancy. Uncertainty prevails regarding a robust association between CHIP and heart transplantation outcomes.

OBJECTIVES

To determine prevalence of CHIP mutations in heart transplantation and their association with long-term outcomes including cardiac allograft vasculopathy (CAV), graft failure, malignancy, and all-cause mortality.

METHODS

We conducted a mixed retrospective-prospective observational study of heart transplant recipients with targeted sequencing for CHIP mutations (Variant allele frequency (VAF) of ≥2%). The primary composite outcome was first occurrence of CAV grade ≥2, graft failure, malignancy, cardiac re-transplantation, or all-cause death. Secondary outcomes were the individual components of the composite primary outcome. Sensitivity analyses with base-case and extreme scenarios were performed.

RESULTS

Among 95 HT recipients, 30 had CHIP mutations (31.6%). DNMT3A mutations were most common (44.7%) followed by PPM1D (13.2%), SF3B1 (10.5%), TET2 (7.9%) and TP53 (7.9%). The only significant independent predictor of CHIP was age at enrollment or age at transplantation. After multivariable adjustment, CHIP was not associated with the primary outcome which occurred in 44 (46.3%) patients (HR=0.487; 95%CI:0.197-1.204; p=0.119), malignancy alone or death.

CONCLUSION

We demonstrated no association between CHIP mutations and post-transplant outcomes including CAV, graft failure, malignancy, and all-cause mortality. In line with previously published data, our analysis provides additional evidence on the lack of clinical value of using CHIP mutations as a biomarker for surveillance in outcomes after heart transplantation.

Whole exome sequencing analyses reveal novel genes in telomere length and their biomedical implications

Telomere length is a putative biomarker of aging and is associated with multiple age-related diseases. There are limited data on the landscape of rare genetic variations in telomere length. Here, we systematically characterize the rare variant associations with leukocyte telomere length (LTL) through exome-wide association study (ExWAS) among 390,231 individuals in the UK Biobank. We identified 18 robust rare-variant genes for LTL, most of which estimated effects on LTL were significant (> 0.2 standard deviation per allele). The biological functions of the rare-variant genes were associated with telomere maintenance and capping and several genes were specifically expressed in the testis. Three novel genes (ASXL1, CFAP58, and TET2) associated with LTL were identified. Phenotypic association analyses indicated significant associations of ASXL1 and TET2 with cancers, age-related diseases, blood assays, and cardiovascular traits. Survival analyses suggested that carriers of ASXL1 or TET2 variants were at increased risk for cancers; diseases of the circulatory, respiratory, and genitourinary systems; and all-cause and cause-specific deaths. The CFAP58 carriers were at elevated risk of deaths due to cancers. Collectively, the present whole exome sequencing study provides novel insights into the genetic landscape of LTL, identifying novel genes associated with LTL and their implications on human health and facilitating a better understanding of aging, thus pinpointing the genetic relevance of LTL with clonal hematopoiesis, biomedical traits, and health-related outcomes.

Epigenetic and proteomic signatures associate with clonal hematopoiesis expansion rate

Clonal hematopoiesis of indeterminate potential (CHIP), whereby somatic mutations in hematopoietic stem cells confer a selective advantage and drive clonal expansion, not only correlates with age but also confers increased risk of morbidity and mortality. Here, we leverage genetically predicted traits to identify factors that determine CHIP clonal expansion rate. We used the passenger-approximated clonal expansion rate method to quantify the clonal expansion rate for 4,370 individuals in the National Heart, Lung, and Blood Institute (NHLBI) Trans-Omics for Precision Medicine (TOPMed) cohort and calculated polygenic risk scores for DNA methylation aging, inflammation-related measures and circulating protein levels. Clonal expansion rate was significantly associated with both genetically predicted and measured epigenetic clocks. No associations were identified with inflammation-related lab values or diseases and CHIP expansion rate overall. A proteome-wide search identified predicted circulating levels of myeloid zinc finger 1 and anti-Müllerian hormone as associated with an increased CHIP clonal expansion rate and tissue inhibitor of metalloproteinase 1 and glycine N-methyltransferase as associated with decreased CHIP clonal expansion rate. Together, our findings identify epigenetic and proteomic patterns associated with the rate of hematopoietic clonal expansion.

Impact of Clonal Hematopoiesis-Associated Mutations in Phase I Patients Treated for Solid Tumors: An Analysis of the STING Trial

PURPOSE

With liquid biopsy's widespread adoption in oncology, an increased number of clonal hematopoiesis-associated mutations (CHm) have been identified in patients with solid tumors. However, its impact on patient outcomes remains unclear. This study aimed to analyze and describe CHm in a cohort of phase I patients.

METHODS

Retrospective data collection from medical records and molecular profiles (Foundation One Liquid CDx Assay) was performed before first study drug administration at the Drug Development Department of Gustave Roussy (France) within the STING trial (ClinicalTrials.gov identifier: NCT04932525). CHm prevalence was assessed using any and ≥1% variant allele frequency (VAF) in epigenetic modifier genes (DNMT3A, TET2, and ASXL1).

RESULTS

From January 2021 to December 2022, 255 patients were enrolled in a phase I clinical trial. A total of 55% were male, with a median age of 62 years (24-86). Principal tumor locations were GI (27%) and genitourinary (21%). Overall, 104 patients (41%) had at least one CHm in liquid biopsy, with 55 patients (22%) having a VAF of ≥ 1%. The most frequent mutation was DNMT3A 73% at any VAF (n = 76) and 22% at 1% VAF (n = 23). Median progression-free survival (PFS) and overall survival were 3.8 months (m) for the CHm group versus 3.2 m for nonclonal hematopoiesis (CH; P = .08) and 18.26 m CHm versus 15.8 m non-CH (P = .9), respectively. PFS increased in the CHm population treated with targeted therapy (hazard ratio, 0.6 [95% CI, 0.42 to 0.84]; P = .004).

CONCLUSION

CHm was commonly found in patients with solid tumors treated in phase I trials, with a prevalence of 41% in our cohort. The most frequently mutated gene was DNMT3A. The presence of CHm had no impact on the population of patients treated in the phase I trials.

Tissue mosaicism following stem cell aging: blood as an exemplar

Loss of stem cell regenerative potential underlies aging of all tissues. Somatic mosaicism, the emergence of cellular patchworks within tissues, increases with age and has been observed in every organ yet examined. In the hematopoietic system, as in most tissues, stem cell aging through a variety of mechanisms occurs in lockstep with the emergence of somatic mosaicism. Here, we draw on insights from aging hematopoiesis to illustrate fundamental principles of stem cell aging and somatic mosaicism. We describe the generalizable changes intrinsic to aged stem cells and their milieu that provide the backdrop for somatic mosaicism to emerge. We discuss genetic and nongenetic mechanisms that can result in tissue somatic mosaicism and existing methodologies to detect such clonal outgrowths. Finally, we propose potential avenues to modify mosaicism during aging, with the ultimate aim of increasing tissue resiliency.

Clonal haematopoiesis, ageing and kidney disease

Clonal haematopoiesis of indeterminate potential (CHIP) is a preclinical condition wherein a sizeable proportion of an individual's circulating blood cells are derived from a single mutated haematopoietic stem cell. CHIP occurs frequently with ageing - more than 10% of individuals over 65 years of age are affected - and is associated with an increased risk of disease across several organ systems and premature death. Emerging evidence suggests that CHIP has a role in kidney health, including associations with predisposition to acute kidney injury, impaired recovery from acute kidney injury and kidney function decline, both in the general population and among those with chronic kidney disease. Beyond its direct effect on the kidney, CHIP elevates the susceptibility of individuals to various conditions that can detrimentally affect the kidneys, including cardiovascular disease, obesity and insulin resistance, liver disease, gout, osteoporosis and certain autoimmune diseases. Aberrant pro-inflammatory signalling, telomere attrition and epigenetic ageing are potential causal pathophysiological pathways and mediators that underlie CHIP-related disease risk. Experimental animal models have shown that inhibition of inflammatory cytokine signalling can ameliorate many of the pathological effects of CHIP, and assessment of the efficacy and safety of this class of medications for human CHIP-associated pathology is ongoing.

Geroscience and pathology: a new frontier in understanding age-related diseases

Geroscience, a burgeoning discipline at the intersection of aging and disease, aims to unravel the intricate relationship between the aging process and pathogenesis of age-related diseases. This paper explores the pivotal role played by geroscience in reshaping our understanding of pathology, with a particular focus on age-related diseases. These diseases, spanning cardiovascular and cerebrovascular disorders, malignancies, and neurodegenerative conditions, significantly contribute to the morbidity and mortality of older individuals. We delve into the fundamental cellular and molecular mechanisms underpinning aging, including mitochondrial dysfunction and cellular senescence, and elucidate their profound implications for the pathogenesis of various age-related diseases. Emphasis is placed on the importance of assessing key biomarkers of aging and biological age within the realm of pathology. We also scrutinize the interplay between cellular senescence and cancer biology as a central area of focus, underscoring its paramount significance in contemporary pathological research. Moreover, we shed light on the integration of anti-aging interventions that target fundamental aging processes, such as senolytics, mitochondria-targeted treatments, and interventions that influence epigenetic regulation within the domain of pathology research. In conclusion, the integration of geroscience concepts into pathological research heralds a transformative paradigm shift in our understanding of disease pathogenesis and promises breakthroughs in disease prevention and treatment.

Germline predisposition for clonal hematopoiesis

Clonal hematopoiesis (CH) is an entity hallmarked by skewed hematopoiesis with persistent overrepresentation of cells from a common stem/progenitor lineage harboring single-nucleotide variants and/or insertions/deletions. CH is a common and age-related phenomenon that is associated with an increased risk of hematological malignancies, cardiovascular disease, and all-cause mortality. While CH is a term of the hematological aspect, there exists a complex interaction with other organ systems, especially the cardiovascular system. The strongest factor in the development of CH is aging, however, other multiple factors also affect the development of CH including lifestyle-related factors and co-morbid diseases. In recent years, germline genetic factors have been linked to CH risk. In this review, we synthesize what is currently known about how genetic variation affects the risk of CH, how this genetic architecture intersects with myeloid neoplasms, and future prospects for CH.

Transcriptional and functional consequences of Oncostatin M signaling on young Dnmt3a-mutant hematopoietic stem cells

Age-associated clonal hematopoiesis (CH) occurs due to somatic mutations accrued in hematopoietic stem cells (HSCs) that confer a selective growth advantage in the context of aging. The mechanisms by which CH-mutant HSCs gain this advantage with aging are not comprehensively understood. Using unbiased transcriptomic approaches, we identified Oncostatin M (OSM) signaling as a candidate contributor to age-related Dnmt3a-mutant CH. We found that Dnmt3a-mutant HSCs from young adult mice (3-6 months old) subjected to acute OSM stimulation do not demonstrate altered proliferation, apoptosis, hematopoietic engraftment, or myeloid differentiation. Dnmt3a-mutant HSCs from young mice do transcriptionally upregulate an inflammatory cytokine network in response to acute in vitro OSM stimulation as evidenced by significant upregulation of the genes encoding IL-6, IL-1β, and TNFα. OSM-stimulated Dnmt3a-mutant HSCs also demonstrate upregulation of the anti-inflammatory genes Socs3, Atf3, and Nr4a1. In the context of an aged bone marrow (BM) microenvironment, Dnmt3a-mutant HSCs upregulate proinflammatory genes but not the anti-inflammatory genes Socs3, Atf3, and Nr4a1. The results from our studies suggest that aging may exhaust the regulatory mechanisms that HSCs employ to resolve inflammatory states in response to factors such as OSM.

Clonal Hematopoiesis, Inflammation, and Hematologic Malignancy

Somatic or acquired mutations are postzygotic genetic variations that can occur within any tissue. These mutations accumulate during aging and have classically been linked to malignant processes. Tremendous advancements over the past years have led to a deeper understanding of the role of somatic mutations in benign and malignant age-related diseases. Here, we review the somatic mutations that accumulate in the blood and their connection to disease states, with a particular focus on inflammatory diseases and myelodysplastic syndrome. We include a definition of clonal hematopoiesis (CH) and an overview of the origins and implications of these mutations. In addition, we emphasize somatic disorders with overlapping inflammation and hematologic disease beyond CH, including paroxysmal nocturnal hemoglobinuria and aplastic anemia, focusing on VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome. Finally, we provide a practical view of the implications of somatic mutations in clinical hematology, pathology, and beyond.

Methods for Estimating Personal Disease Risk and Phylogenetic Diversity of Hematopoietic Stem Cells

An individual's chronological age does not always correspond to the health of different tissues in their body, especially in cases of disease. Therefore, estimating and contrasting the physiological age of tissues with an individual's chronological age may be a useful tool to diagnose disease and its progression. In this study, we present novel metrics to quantify the loss of phylogenetic diversity in hematopoietic stem cells (HSCs), which are precursors to most blood cell types and are associated with many blood-related diseases. These metrics showed an excellent correspondence with an age-related increase in blood cancer incidence, enabling a model to estimate the phylogeny-derived age (phyloAge) of HSCs present in an individual. The HSC phyloAge was generally older than the chronological age of patients suffering from myeloproliferative neoplasms (MPNs). We present a model that relates excess HSC aging with increased MPN risk. It predicted an over 200 times greater risk based on the HSC phylogenies of the youngest MPN patients analyzed. Our new metrics are designed to be robust to sampling biases and do not rely on prior knowledge of driver mutations or physiological assessments. Consequently, they complement conventional biomarker-based methods to estimate physiological age and disease risk.

Epigenetic Mechanisms in Hematologic Aging and Premalignant Conditions

Hematopoietic stem cells (HSCs) are essential for maintaining overall health by continuously generating blood cells throughout an individual's lifespan. However, as individuals age, the hematopoietic system undergoes significant functional decline, rendering them more susceptible to age-related diseases. Growing research evidence has highlighted the critical role of epigenetic regulation in this age-associated decline. This review aims to provide an overview of the diverse epigenetic mechanisms involved in the regulation of normal HSCs during the aging process and their implications in aging-related diseases. Understanding the intricate interplay of epigenetic mechanisms that contribute to aging-related changes in the hematopoietic system holds great potential for the development of innovative strategies to delay the aging process. In fact, interventions targeting epigenetic modifications have shown promising outcomes in alleviating aging-related phenotypes and extending lifespan in various animal models. Small molecule-based therapies and reprogramming strategies enabling epigenetic rejuvenation have emerged as effective approaches for ameliorating or even reversing aging-related conditions. By acquiring a deeper understanding of these epigenetic mechanisms, it is anticipated that interventions can be devised to prevent or mitigate the rates of hematologic aging and associated diseases later in life. Ultimately, these advancements have the potential to improve overall health and enhance the quality of life in aging individuals.

Somatic mutation as an explanation for epigenetic aging

DNA methylation marks have recently been used to build models known as "epigenetic clocks" which predict calendar age. As methylation of cytosine promotes C-to-T mutations, we hypothesized that the methylation changes observed with age should reflect the accrual of somatic mutations, and the two should yield analogous aging estimates. In analysis of multimodal data from 9,331 human individuals, we find that CpG mutations indeed coincide with changes in methylation, not only at the mutated site but also with pervasive remodeling of the methylome out to ±10 kilobases. This one-to-many mapping enables mutation-based predictions of age that agree with epigenetic clocks, including which individuals are aging faster or slower than expected. Moreover, genomic loci where mutations accumulate with age also tend to have methylation patterns that are especially predictive of age. These results suggest a close coupling between the accumulation of sporadic somatic mutations and the widespread changes in methylation observed over the course of life.

Flattening the biological age curve by improving metabolic health: to taurine or not to taurine, that' s the question

The aging population is an important issue around the world especially in developed countries. Although medical advances have substantially extended life span, the same cannot be said for the duration of health span. We are seeing increasing numbers of elderly people who are frail and/or have multiple chronic conditions; all of these can affect the quality of life of the elderly population as well as increase the burden on the healthcare system. Aging is mechanistically related to common medical conditions such as diabetes mellitus, ischemic heart disease, cognitive decline, and frailty. A recently accepted concept termed 'Accelerated Biological Aging' can be diagnosed when a person's biological age-as measured by biomarkers of DNA methylation-is older than their corresponding chronological age. Taurine, a conditionally essential amino acid, has received much attention in the past few years. A substantial number of animal studies have provided a strong scientific foundation suggesting that this amino acid can improve cellular and metabolic health, including blood glucose control, so much that it has been labelled one of the 'longevity amino acids'. In this review article, we propose the rationale that an adequately powered randomized-controlled-trial (RCT) is needed to confirm whether taurine can meaningfully improve metabolic and microbiome health, and biological age. This trial should incorporate certain elements in order to provide the much-needed evidence to guide doctors, and also the community at large, to determine whether this promising and inexpensive amino acid is useful in improving human metabolic health.

The Cutting Edge of Epigenetic Clocks: In Search of Mechanisms Linking Aging and Mental Health

Individuals with psychiatric disorders are at increased risk of age-related diseases and early mortality. Recent studies demonstrate that this link between mental health and aging is reflected in epigenetic clocks, aging biomarkers based on DNA methylation. The reported relationships between epigenetic clocks and mental health are mostly correlational, and the mechanisms are poorly understood. Here, we review recent progress concerning the molecular and cellular processes underlying epigenetic clocks as well as novel technologies enabling further studies of the causes and consequences of epigenetic aging. We then review the current literature on how epigenetic clocks relate to specific aspects of mental health, such as stress, medications, substance use, health behaviors, and symptom clusters. We propose an integrated framework where mental health and epigenetic aging are each broken down into multiple distinct processes, which are then linked to each other, using stress and schizophrenia as examples. This framework incorporates the heterogeneity and complexity of both mental health conditions and aging, may help reconcile conflicting results, and provides a basis for further hypothesis-driven research in humans and model systems to investigate potentially causal mechanisms linking aging and mental health.

Clonal Hematopoiesis of Indeterminate Potential (CHIP) and Incident Type 2 Diabetes Risk

OBJECTIVE

Clonal hematopoiesis of indeterminate potential (CHIP) is an aging-related accumulation of somatic mutations in hematopoietic stem cells, leading to clonal expansion. CHIP presence has been implicated in atherosclerotic coronary heart disease (CHD) and all-cause mortality, but its association with incident type 2 diabetes (T2D) is unknown. We hypothesized that CHIP is associated with elevated risk of T2D.

RESEARCH DESIGN AND METHODS

CHIP was derived from whole-genome sequencing of blood DNA in the National Heart, Lung, and Blood Institute Trans-Omics for Precision Medicine (TOPMed) prospective cohorts. We performed analysis for 17,637 participants from six cohorts, without prior T2D, cardiovascular disease, or cancer. We evaluated baseline CHIP versus no CHIP prevalence with incident T2D, including associations with DNMT3A, TET2, ASXL1, JAK2, and TP53 variants. We estimated multivariable-adjusted hazard ratios (HRs) and 95% CIs with adjustment for age, sex, BMI, smoking, alcohol, education, self-reported race/ethnicity, and combined cohorts' estimates via fixed-effects meta-analysis.

RESULTS

Mean (SD) age was 63.4 (11.5) years, 76% were female, and CHIP prevalence was 6.0% (n = 1,055) at baseline. T2D was diagnosed in n = 2,467 over mean follow-up of 9.8 years. Participants with CHIP had 23% (CI 1.04, 1.45) higher risk of T2D than those with no CHIP. Specifically, higher risk was for TET2 (HR 1.48; CI 1.05, 2.08) and ASXL1 (HR 1.76; CI 1.03, 2.99) mutations; DNMT3A was nonsignificant (HR 1.15; CI 0.93, 1.43). Statistical power was limited for JAK2 and TP53 analyses.

CONCLUSIONS

CHIP was associated with higher incidence of T2D. CHIP mutations located on genes implicated in CHD and mortality were also related to T2D, suggesting shared aging-related pathology.

Biological age as a predictor of unplanned intensive care readmission during the same hospitalization

BACKGROUND

Biological age is increasingly being recognized as an important predictor of health but its utility in acute care setting remains uncertain.

OBJECTIVE

We assessed whether biological age on intensive care unit (ICU) admission can predict unplanned ICU readmission during the same hospitalization.

METHODS

The Levine PhenoAge model based on biomarkers of DNA methylation was used to determine each patient's biological age. The difference between PhenoAge and chronological age was indexed to the local context by regressing PhenoAge on chronological age using linear regression. A positive residual implied one's biological age was older than the corresponding chronological age compared to other patients - defined as PhenoAgeAccel.

RESULTS

Of the 2950 patients included, 153 (5.2%) had unplanned ICU readmission. Chronological age, Acute Physiology and Chronic Health Evaluation II score, the use of mechanical ventilation, vasopressor, or renal replacement therapy were not significantly different between those with and without readmission. PhenoAgeAccel was, however, more common among those who had unplanned ICU readmission (52% vs 43%, p =0.031). Quantitatively, the degree of phenotypical age above chronological age exhibited a 'dose-related' relationship with the risk of readmission (odds ratio 1.12, 95% confidence interval 1.01-1.24; p=0.040) after adjusting for chronological age, comorbidities, and severity of acute illness in the index (first) ICU admission.

CONCLUSION

Biological age was predictive of unplanned ICU readmission during the same hospitalization.

Epigenetic roles in clonal hematopoiesis and aging kidney-related chronic kidney disease

Accumulation of somatic hematopoietic stem cell mutations with aging has been revealed by the recent genome-wide analysis. Clonal expansion, known as clonal hematopoiesis of indeterminate potential (CHIP), is a premalignant condition of hematological cancers. It is defined as the absence of definitive morphological evidence of a hematological neoplasm and occurrence of ≥2% of mutant allele fraction in the peripheral blood. In CHIP, the most frequently mutated genes are epigenetic regulators such as DNMT3A, TET2, and ASXL1. CHIP induces inflammation. CHIP is shown to be associated with not only hematological malignancy but also non-malignant disorders such as atherosclerosis, cardiovascular diseases and chronic liver disease. In addition, recent several large clinical trials have shown that CHIP is also the risk factor for developing chronic kidney disease (CKD). In this review article, we proposed novel findings about CHIP and CHIP related kidney disease based on the recent basic and clinical research. The possible mechanism of the kidney injury in CHIP is supposed to be due to the clonal expansion in both myeloid and lymphoid cell lines. In myeloid cell lines, the mutated macrophages increase the inflammatory cytokine level and induce chronic inflammation. It leads to epigenetic downregulation of kidney and macrophage klotho level. In lymphoid cell lines, CHIP might be related to monoclonal gammopathy of renal significance (MGRS). It describes any B cell or plasma cell clonal disorder that does not fulfill the criteria for cancer yet produces a nephrotoxic monoclonal immunoglobulin that leads to kidney injury or disease. MGRS causes M-protein related nephropathy frequently observed among aged CKD patients. It is important to consider the CHIP-related complications such as hematological malignancy, cardiovascular diseases and metabolic disorders in managing the elderly CKD patients. There are no established therapies for CHIP and CHIP-related CKD yet. However, recent studies have supported the development of effective CHIP therapies, such as blocking the expansion of aberrant HSCs and inhibiting chronic inflammation. In addition, drugs targeting the epigenetic regulation of Klotho in the kidney and macrophages might be therapeutic targets of CHIP in the kidney.

Biological age is superior to chronological age in predicting hospital mortality of the critically ill

Biological age is increasingly recognized as being more accurate than chronological age in determining chronic health outcomes. This study assessed whether biological age, assessed on intensive care unit (ICU) admission, can predict hospital mortality. This retrospective cohort study, conducted in a tertiary multidisciplinary ICU in Western Australia, used the Levine PhenoAge model to estimate each patient's biological age (also called PhenoAge). Each patient's PhenoAge was calibrated to generate a regression residual which was equivalent to biological age unexplained by chronological age in the local context. PhenoAgeAccel was a dichotomized measure of the residuals, and its presence suggested that one was biologically older than the corresponding chronological age. Of the 2950 critically ill adult patients analyzed, 291 died (9.9%) before hospital discharge. Both PhenoAge and its residuals (after regressing on chronological age) had a significantly better ability to differentiate between hospital survivors and non-survivors than chronological age (area under the receiver-operating-characteristic curve 0.648 and 0.654 vs. 0.547 respectively). Being phenotypically older than one's chronological age was associated with an increased risk of mortality (PhenoAgeAccel hazard ratio [HR] 1.997, 95% confidence interval [CI] 1.568-2.542; p = 0.001) in a dose-related fashion and did not reach a plateau until at least a 20-year gap. This adverse association remained significant (adjusted HR 1.386, 95% CI 1.077-1.784; p = 0.011) after adjusted for severity of acute illness and comorbidities. PhenoAgeAccel was more prevalent among those with pre-existing chronic cardiovascular disease, end-stage renal failure, cirrhosis, immune disease, diabetes mellitus, or those treated with immunosuppressive therapy. Being phenotypically older than one's chronological age was more common among those with comorbidities, and this was associated with an increased risk of mortality in a dose-related fashion in the critically ill that was not fully explained by comorbidities and severity of acute illness.

Simultaneous sequencing of genetic and epigenetic bases in DNA

DNA comprises molecular information stored in genetic and epigenetic bases, both of which are vital to our understanding of biology. Most DNA sequencing approaches address either genetics or epigenetics and thus capture incomplete information. Methods widely used to detect epigenetic DNA bases fail to capture common C-to-T mutations or distinguish 5-methylcytosine from 5-hydroxymethylcytosine. We present a single base-resolution sequencing methodology that sequences complete genetics and the two most common cytosine modifications in a single workflow. DNA is copied and bases are enzymatically converted. Coupled decoding of bases across the original and copy strand provides a phased digital readout. Methods are demonstrated on human genomic DNA and cell-free DNA from a blood sample of a patient with cancer. The approach is accurate, requires low DNA input and has a simple workflow and analysis pipeline. Simultaneous, phased reading of genetic and epigenetic bases provides a more complete picture of the information stored in genomes and has applications throughout biomedicine.

Aging and Age-Related Epigenetic Drift in the Pathogenesis of Leukemia and Lymphomas: New Therapeutic Targets

One of the traits of cancer cells is abnormal DNA methylation patterns. The idea that age-related epigenetic changes may partially explain the increased risk of cancer in the elderly is based on the observation that aging is also accompanied by comparable changes in epigenetic patterns. Lineage bias and decreased stem cell function are signs of hematopoietic stem cell compartment aging. Additionally, aging in the hematopoietic system and the stem cell niche have a role in hematopoietic stem cell phenotypes linked with age, such as leukemia and lymphoma. Understanding these changes will open up promising pathways for therapies against age-related disorders because epigenetic mechanisms are reversible. Additionally, the development of high-throughput epigenome mapping technologies will make it possible to identify the "epigenomic identity card" of every hematological disease as well as every patient, opening up the possibility of finding novel molecular biomarkers that can be used for diagnosis, prediction, and prognosis.

Clonal haematopoiesis and dysregulation of the immune system

Age-related diseases are frequently linked to pathological immune dysfunction, including excessive inflammation, autoreactivity and immunodeficiency. Recent analyses of human genetic data have revealed that somatic mutations and mosaic chromosomal alterations in blood cells - a condition known as clonal haematopoiesis (CH) - are associated with ageing and pathological immune dysfunction. Indeed, large-scale epidemiological studies and experimental mouse models have demonstrated that CH can promote cardiovascular disease, chronic obstructive pulmonary disease, chronic liver disease, osteoporosis and gout. The genes most frequently mutated in CH, the epigenetic regulators TET2 and DNMT3A, implicate increased chemokine expression and inflammasome hyperactivation in myeloid cells as a possible mechanistic connection between CH and age-related diseases. In addition, TET2 and DNMT3A mutations in lymphoid cells have been shown to drive methylation-dependent alterations in differentiation and function. Here we review the observational and mechanistic studies describing the connection between CH and pathological immune dysfunction, the effects of CH-associated genetic alterations on the function of myeloid and lymphoid cells, and the clinical and therapeutic implications of CH as a target for immunomodulation.

New insight into the causes, consequences, and correction of hematopoietic stem cell aging

Aging of hematopoietic stem cells (HSCs) is characterized by lineage bias, increased clonal expansion, and functional decrease. At the molecular level, aged HSCs typically display metabolic dysregulation, upregulation of inflammatory pathways, and downregulation of DNA repair pathways. Cellular aging of HSCs, driven by cell-intrinsic and cell-extrinsic factors, causes a predisposition to anemia, adaptive immune compromise, myelodys, plasia, and malignancy. Most hematologic diseases are strongly associated with age. But what is the biological foundation for decreased fitness with age? And are there therapeutic windows to resolve age-related hematopoietic decline? These questions were the focus of the International Society for Experimental Hematology (ISEH) New Investigator Committee Fall 2022 Webinar. This review touches on the latest insights from two leading laboratories into inflammatory- and niche-driven stem cell aging and includes speculation on strategies to prevent or correct age-related decline in HSC function.

Molecular Studies for the Early Detection of Philadelphia-Negative Myeloproliferative Neoplasms

JAK2 V617F is the predominant driver mutation in patients with Philadelphia-negative myeloproliferative neoplasms (MPN). JAK2 mutations are also frequent in clonal hematopoiesis of indeterminate potential (CHIP) in otherwise "healthy" individuals. However, the period between mutation acquisition and MPN diagnosis (known as latency) varies widely between individuals, with JAK2 mutations detectable several decades before diagnosis and even from birth in some individuals. Here, we will review the current evidence on the biological factors, such as additional mutations and chronic inflammation, which influence clonal expansion and may determine why some JAK2-mutated individuals will progress to an overt neoplasm during their lifetime while others will not. We will also introduce several germline variants that predispose individuals to CHIP (as well as MPN) identified from genome-wide association studies. Finally, we will explore possible mutation screening or interventions that could help to minimize MPN-associated cardiovascular complications or even delay malignant progression.

Clonal Hematopoiesis of Indeterminate Potential From a Heart Failure Specialist's Point of View

Clonal hematopoiesis of indeterminate potential (CHIP) is a common bone marrow abnormality induced by age-related DNA mutations, which give rise to proinflammatory immune cells. These immune cells exacerbate atherosclerotic cardiovascular disease and may induce or accelerate heart failure. The mechanisms involved are complex but point toward a central role for proinflammatory macrophages and an inflammasome-dependent immune response (IL-1 [interleukin-1] and IL-6 [interleukin-6]) in the atherosclerotic plaque or directly in the myocardium. Intracardiac inflammation may decrease cardiac function and induce cardiac fibrosis, even in the absence of atherosclerotic cardiovascular disease. The pathophysiology and consequences of CHIP may differ among implicated genes as well as subgroups of patients with heart failure, based on cause (ischemic versus nonischemic) and ejection fraction (reduced ejection fraction versus preserved ejection fraction). Evidence is accumulating that CHIP is associated with cardiovascular mortality in ischemic and nonischemic heart failure with reduced ejection fraction and involved in the development of heart failure with preserved ejection fraction. CHIP and corresponding inflammatory pathways provide a highly potent therapeutic target. Randomized controlled trials in patients with well-phenotyped heart failure, where readily available anti-inflammatory therapies are used to intervene with clonal hematopoiesis, may pave the way for a new area of heart failure treatment. The first clinical trials that target CHIP are already registered.

Spectrum of clonal hematopoiesis in VEXAS syndrome

Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome is caused by somatic mutations in UBA1 (UBA1mut) and characterized by heterogenous systemic autoinflammation and progressive hematologic manifestations, meeting criteria for myelodysplastic syndrome (MDS) and plasma cell dyscrasias. The landscape of myeloid-related gene mutations leading to typical clonal hematopoiesis (CH) in these patients is unknown. Retrospectively, we screened 80 patients with VEXAS for CH in their peripheral blood (PB) and correlated the findings with clinical outcomes in 77 of them. UBA1mut were most common at hot spot p.M41 (median variant allele frequency [VAF] = 75%). Typical CH mutations cooccurred with UBA1mut in 60% of patients, mostly in DNMT3A and TET2, and were not associated with inflammatory or hematologic manifestations. In prospective single-cell proteogenomic sequencing (scDNA), UBA1mut was the dominant clone, present mostly in branched clonal trajectories. Based on integrated bulk and scDNA analyses, clonality in VEXAS followed 2 major patterns: with either typical CH preceding UBA1mut selection in a clone (pattern 1) or occurring as an UBA1mut subclone or in independent clones (pattern 2). VAF in the PB differed markedly between DNMT3A and TET2 clones (median VAF of 25% vs 1%). DNMT3A and TET2 clones associated with hierarchies representing patterns 1 and 2, respectively. Overall survival for all patients was 60% at 10 years. Transfusion-dependent anemia, moderate thrombocytopenia, and typical CH mutations, each correlated with poor outcome. In VEXAS, UBA1mut cells are the primary cause of systemic inflammation and marrow failure, being a new molecularly defined somatic entity associated with MDS. VEXAS-associated MDS is distinct from classical MDS in its presentation and clinical course.

Oncostatin M is a Master Regulator of an Inflammatory Network in Dnmt3a -Mutant Hematopoietic Stem Cells

Age-associated clonal hematopoiesis (CH) occurs due to somatic mutations accrued in hematopoietic stem cells (HSCs) that confer a selective advantage in the context of aging. The mechanisms by which CH-mutant HSCs gain this advantage with aging are not comprehensively understood. Using unbiased transcriptomic approaches, we identify Oncostatin M (OSM) signaling as a candidate contributor to aging-driven Dnmt3a -mutant CH. We find that Dnmt3a -mutant HSCs from young mice do not functionally respond to acute OSM stimulation with respect to proliferation, apoptosis, hematopoietic engraftment, or myeloid differentiation. However, young Dnmt3a -mutant HSCs transcriptionally upregulate an inflammatory cytokine network in response to acute OSM stimulation including genes encoding IL-6, IL-1β and TNFα. In addition, OSM-stimulated Dnmt3a -mutant HSCs upregulate the anti-inflammatory genes Socs3, Atf3 and Nr4a1 , creating a negative feedback loop limiting sustained activation of the inflammatory network. In the context of an aged bone marrow (BM) microenvironment with chronically elevated levels of OSM, Dnmt3a -mutant HSCs upregulate pro-inflammatory genes but do not upregulate Socs3, Atf3 and Nr4a1 . Together, our work suggests that chronic inflammation with aging exhausts the regulatory mechanisms in young CH-mutant HSCs that resolve inflammatory states, and that OSM is a master regulator of an inflammatory network that contributes to age-associated CH.

Clonal hematopoiesis is associated with protection from Alzheimer's disease

Clonal hematopoiesis of indeterminate potential (CHIP) is a premalignant expansion of mutated hematopoietic stem cells. As CHIP-associated mutations are known to alter the development and function of myeloid cells, we hypothesized that CHIP may also be associated with the risk of Alzheimer's disease (AD), a disease in which brain-resident myeloid cells are thought to have a major role. To perform association tests between CHIP and AD dementia, we analyzed blood DNA sequencing data from 1,362 individuals with AD and 4,368 individuals without AD. Individuals with CHIP had a lower risk of AD dementia (meta-analysis odds ratio (OR) = 0.64, P = 3.8 × 10-5), and Mendelian randomization analyses supported a potential causal association. We observed that the same mutations found in blood were also detected in microglia-enriched fraction of the brain in seven of eight CHIP carriers. Single-nucleus chromatin accessibility profiling of brain-derived nuclei in six CHIP carriers revealed that the mutated cells comprised a large proportion of the microglial pool in the samples examined. While additional studies are required to validate the mechanistic findings, these results suggest that CHIP may have a role in attenuating the risk of AD.

Transcription factor genetics and biology in predisposition to bone marrow failure and hematological malignancy

Transcription factors (TFs) play a critical role as key mediators of a multitude of developmental pathways, with highly regulated and tightly organized networks crucial for determining both the timing and pattern of tissue development. TFs can act as master regulators of both primitive and definitive hematopoiesis, tightly controlling the behavior of hematopoietic stem and progenitor cells (HSPCs). These networks control the functional regulation of HSPCs including self-renewal, proliferation, and differentiation dynamics, which are essential to normal hematopoiesis. Defining the key players and dynamics of these hematopoietic transcriptional networks is essential to understanding both normal hematopoiesis and how genetic aberrations in TFs and their networks can predispose to hematopoietic disease including bone marrow failure (BMF) and hematological malignancy (HM). Despite their multifaceted and complex involvement in hematological development, advances in genetic screening along with elegant multi-omics and model system studies are shedding light on how hematopoietic TFs interact and network to achieve normal cell fates and their role in disease etiology. This review focuses on TFs which predispose to BMF and HM, identifies potential novel candidate predisposing TF genes, and examines putative biological mechanisms leading to these phenotypes. A better understanding of the genetics and molecular biology of hematopoietic TFs, as well as identifying novel genes and genetic variants predisposing to BMF and HM, will accelerate the development of preventative strategies, improve clinical management and counseling, and help define targeted treatments for these diseases.

Biomarkers of aging through the life course: A Recent Literature Update

Purpose of review

The development of biomarkers of aging has greatly advanced epidemiological studies of aging processes. However, much debate remains on the timing of aging onset and the causal relevance of these biomarkers. In this review, we discuss the most recent biomarkers of aging that have been applied across the life course.

Recent findings

The most recently developed aging biomarkers that have been applied across the life course can be designated into three categories: epigenetic clocks, epigenetic markers of chronic inflammation, and mitochondrial DNA copy number. While these have been applied at different life stages, the development, validation, and application of these markers has been largely centered on populations of older adults. Few studies have examined trajectories of aging biomarkers across the life course. As the wealth of molecular and biochemical data increases, emerging biomarkers may be able to capture complex and system-specific aging processes. Recently developed biomarkers include novel epigenetic clocks; clocks based on ribosomal DNA, transcriptomic profiles, proteomics, metabolomics, and inflammatory markers; clonal hematopoiesis of indeterminate potential gene mutations; and multi-omics approaches.

Summary

Attention should be placed on aging at early and middle life stages to better understand trajectories of aging biomarkers across the life course. Additionally, novel biomarkers will provide greater insight into aging processes. The specific mechanisms of aging reflected by these biomarkers should be considered when interpreting results.

Emerging evidence on the role of clonal hematopoiesis of indeterminate potential in chronic kidney disease

Chronic kidney disease (CKD) was responsible for 1.2 million deaths globally in 2016. Despite the large and growing burden of CKD, treatment options are limited and generally only preserve kidney function. Characterizing molecular precursors to incident and progressive CKD could point to critically needed prevention and treatment strategies. Clonal hematopoiesis of indeterminate potential (CHIP) is typically characterized by the clonal expansion of blood cells carrying somatic mutations in specific driver genes. An age-related disorder, CHIP is rare in the young but common in older adults. Recent studies have identified causal associations between CHIP and atherosclerotic cardiovascular disease which are most likely mediated by inflammation, a hallmark of CKD. Animal evidence has supported causal effects of CHIP on kidney injury, inflammation, and fibrosis, providing impetus for human research. Although prospective epidemiologic studies investigating associations of CHIP with development and progression of CKD are few, intriguing findings have been reported. CHIP was significantly associated with kidney function decline and end stage kidney disease in the general population, although effect sizes were modest. Recent work suggests larger associations of CHIP with kidney disease progression in CKD patients, but further investigations in this area are needed. In addition, the accumulating literature has identified some heterogeneity in associations between CHIP and kidney endpoints across study populations, but reasons for these differences remain unclear. The current review provides an in-depth exploration into this nascent area of research, develops a conceptual framework linking CHIP to CKD, and discusses the clinical and public health implications of this work.

Blockade of IL-6 signaling alleviates atherosclerosis in Tet2-deficient clonal hematopoiesis

Clonal hematopoiesis (CH) increases the risk of atherosclerotic cardiovascular disease possibly due to increased plaque inflammation. Human studies suggest that limitation of interleukin-6 (IL-6) signaling could be beneficial in people with large CH clones, particularly in TET2 CH. Here we show that IL-6 receptor antibody treatment reverses the atherosclerosis promoted by Tet2 CH, with reduction of monocytosis, lesional macrophage burden and macrophage colony-stimulating factor 1 receptor (CSF1R) expression. IL-6 induces expression of Csf1r in Tet2-deficient macrophages through enhanced STAT3 binding to its promoter. In mouse and human Tet2-deficient macrophages, IL-6 increases CSF1R expression and enhances macrophage survival. Treatment with the CSF1R inhibitor PLX3397 reversed accelerated atherosclerosis in Tet2 CH mice. Our study demonstrates the causality of IL-6 signaling in Tet2 CH accelerated atherosclerosis, identifies IL-6-induced CSF1R expression as a critical mechanism and supports blockade of IL-6 signaling as a potential therapy for CH-driven cardiovascular disease.

Time to relapse in chronic lymphocytic leukemia and DNA-methylation-based biological age

Chronic lymphocytic leukemia (CLL) is a mature B cell neoplasm with a predilection for older individuals. While previous studies have identified epigenetic signatures associated with CLL, whether age-related DNA methylation changes modulate CLL relapse remains elusive. In this study, we examined the association between epigenetic age acceleration and time to CLL relapse in a publicly available dataset. DNA methylation profiling of 35 CLL patients prior to initiating chemoimmunotherapy was performed using the Infinium HumanMethylation450 BeadChip. Four epigenetic age acceleration metrics (intrinsic epigenetic age acceleration [IEAA], extrinsic epigenetic age acceleration [EEAA], PhenoAge acceleration [PhenoAA], and GrimAge acceleration [GrimAA]) were estimated from blood DNA methylation levels. Linear, quantile, and logistic regression and receiver operating characteristic curve analyses were conducted to assess the association between each epigenetic age metric and time to CLL relapse. EEAA (p = 0.011) and PhenoAA (p = 0.046) were negatively and GrimAA (p = 0.040) was positively associated with time to CLL relapse. Simultaneous assessment of EEAA and GrimAA in male patients distinguished patients who relapsed early from patients who relapsed later (p = 0.039). No associations were observed with IEAA. These findings suggest epigenetic age acceleration prior to chemoimmunotherapy initiation is associated with time to CLL relapse. Our results provide novel insight into the association between age-related DNA methylation changes and CLL relapse and may serve has biomarkers for treatment relapse, and potentially, treatment selection.

CHIPing away the progression potential of CHIP: A new reality in the making

Over the past few years, we have gained a deeper understanding of clonal hematopoiesis of indeterminate potential (CHIP), especially with regard to the epidemiology, clinical sequelae, and mechanical aspects. However, interventional strategies to prevent or delay the potential negative consequences of CHIP remain underdeveloped. In this review, we highlight the latest updates on clonal hematopoiesis research, including molecular mechanisms and clinical implications, with a particular focus on the evolving strategies for the interventions that are being evaluated in ongoing observational and interventional trials. There remains an urgent need to formulate standardized and evidence-based recommendations and guidelines for evaluating and managing individuals with clonal hematopoiesis. In addition, patient-centric endpoints must be defined for clinical trials, which will enable us to continue the robust development of effective preventive strategies and improve clinical outcomes.

A new risk factor associated with cardiovascular disease: clonal hematopoiesis of indeterminate potential

Clonal hematopoiesis is a prevalent disease associated with all-cause death. Not only because it can be a precancerous lesion of blood system diseases but also has a strong association with cardiovascular disease. A narrow term, clonal hematopoiesis of indeterminate potential (CHIP), was proposed by Steensma et al. [1] to describe individuals with detectable somatic clonal mutations in their genes in blood or bone marrow but without a diagnosis of hematological disease or unexplained cytopenia. Recently, studies have suggested that CHIP is associated with adverse cardiovascular disease progression, particularly in patients with ten-eleven translocation 2 (TET2) mutations or DNA methyltransferase 3 alpha (DNMT3A) mutations. Age is the most crucial factor which is associated with increased CHIP prevalence. The underlying mechanisms appear to be related to inflammatory status. However, new evidence suggests that genetic factors, lifestyle and environmental factors such as smoking, obesity, and diet also play essential roles in developing CHIP. More research needs to be done on the potential genetic mechanisms driving CHIP and the environmental factors that modulate CHIP risk. This review summarizes the latest research on CHIP, discusses in detail the strong association between clonal hematopoiesis and accelerated cardiovascular disease, and rationalizes the intervention of CHIP in combination with existing evidence, which may be beneficial for future treatment.

Clonal Hematopoiesis and Its Impact on Human Health

Aging is associated with increased mutational burden in every tissue studied. Occasionally, fitness-increasing mutations will arise, leading to stem cell clonal expansion. This process occurs in several tissues but has been best studied in blood. Clonal hematopoiesis is associated with an increased risk of blood cancers, such as acute myeloid leukemia, which result if additional cooperating mutations occur. Surprisingly, it is also associated with an increased risk of nonmalignant diseases, such as atherosclerotic cardiovascular disease. This may be due to enhanced inflammation in mutated innate immune cells, which could be targeted clinically with anti-inflammatory drugs. Recent studies have uncovered other factors that predict poor outcomes in patients with clonal hematopoiesis, such as size of the mutant clone, mutated driver genes, and epigenetic aging. Though clonality is inevitable and largely a function of time, recent work has shown that inherited genetic variation can also influence this process. Clonal hematopoiesis provides a paradigm for understanding how age-related changes in tissue stem cell composition and function influence human health.

Long-term risk associated with clonal hematopoiesis in patients with severe aortic valve stenosis undergoing TAVR

BACKGROUND

Mutations in the clonal hematopoiesis of indeterminate potential (CHIP)-driver genes DNMT3A and TET2 have been previously shown to be associated with short-term prognosis in patients undergoing TAVR for aortic valve stenosis. We aimed to extend and characterize these findings on long-term outcome in a large cohort.

METHODS

A total of 453 consecutive patients undergoing TAVR were included in an up to 4-year follow-up study. Next-generation sequencing was used to identify DNMT3A- and/or TET2-CHIP-driver mutations. Primary endpoint was all-cause mortality. Since CHIP-driver mutations appear to be closely related to DNA methylation, results were also assessed in patients who never smoked, a factor known to interfere with DNA methylation.

RESULTS

DNMT3A-/TET2-CHIP-driver mutations were present in 32.4% of patients (DNMT3A n = 92, TET2 n = 71), and were more frequent in women (52.4% vs. 38.9%, p = 0.007) and older participants (83.3 vs. 82.2 years, p = 0.011), while clinical characteristics or blood-derived parameters did not differ. CHIP-driver mutations were associated with a significantly higher mortality up to 4 years after TAVR in both univariate (p = 0.031) and multivariate analyses (HR 1.429, 95%CI 1.014-2.013, p = 0.041). The difference was even more pronounced (p = 0.011) in never smokers. Compared to TET2 mutation carriers, patients with DNMT3A mutations had significantly less frequently concomitant coronary and peripheral artery disease.

CONCLUSION

DNMT3A- and TET2-CHIP-driver mutations are associated with long-term mortality in patients with aortic valve stenosis even after a successful TAVR. The association is also present in never smokers, in whom no biasing effect from smoking on DNA methylation is to be expected.

Clonal hematopoiesis, somatic mosaicism, and age-associated disease

Somatic mosaicism, the occurrence of multiple genetically distinct cell clones within the same tissue, is an evitable consequence of human aging. The hematopoietic system is no exception to this, where studies have revealed the presence of expanded blood cell clones carrying mutations in preleukemic driver genes and/or genetic alterations in chromosomes. This phenomenon is referred to as clonal hematopoiesis and is remarkably prevalent in elderly individuals. While clonal hematopoiesis represents an early step toward a hematological malignancy, most individuals will never develop blood cancer. Somewhat unexpectedly, epidemiological studies have found that clonal hematopoiesis is associated with an increase in the risk of all-cause mortality and age-related disease, particularly in the cardiovascular system. Studies using murine models of clonal hematopoiesis have begun to shed light on this relationship, suggesting that driver mutations in mature blood cells can causally contribute to aging and disease by augmenting inflammatory processes. Here we provide an up-to-date review of clonal hematopoiesis within the context of somatic mosaicism and aging and describe recent epidemiological studies that have reported associations with age-related disease. We will also discuss the experimental studies that have provided important mechanistic insight into how driver mutations promote age-related disease and how this knowledge could be leveraged to treat individuals with clonal hematopoiesis.

Multi-omics and machine learning for the prevention and management of female reproductive health

Females typically carry most of the burden of reproduction in mammals. In humans, this burden is exacerbated further, as the evolutionary advantage of a large and complex human brain came at a great cost of women's reproductive health. Pregnancy thus became a highly demanding phase in a woman's life cycle both physically and emotionally and therefore needs monitoring to assure an optimal outcome. Moreover, an increasing societal trend towards reproductive complications partly due to the increasing maternal age and global obesity pandemic demands closer monitoring of female reproductive health. This review first provides an overview of female reproductive biology and further explores utilization of large-scale data analysis and -omics techniques (genomics, transcriptomics, proteomics, and metabolomics) towards diagnosis, prognosis, and management of female reproductive disorders. In addition, we explore machine learning approaches for predictive models towards prevention and management. Furthermore, mobile apps and wearable devices provide a promise of continuous monitoring of health. These complementary technologies can be combined towards monitoring female (fertility-related) health and detection of any early complications to provide intervention solutions. In summary, technological advances (e.g., omics and wearables) have shown a promise towards diagnosis, prognosis, and management of female reproductive disorders. Systematic integration of these technologies is needed urgently in female reproductive healthcare to be further implemented in the national healthcare systems for societal benefit.

Role of endocrine PACAP in age-related diseases

Pituitary adenylate cyclase activating polypeptide (PACAP) is a conserved neuropeptide, which confers diverse anti-aging endocrine and paracrine/autocrine effects, including anti-apoptotic, anti-inflammatory and antioxidant action. The results of the in vivo and in vitro experiments show that increasing emphasis is being placed on the diagnostic/prognostic biomarker potential of this neuropeptide in a wide array of age-related diseases. After the initial findings regarding the presence and alteration of PACAP in different body fluids in physiological processes, an increasing number of studies have focused on the changes of its levels in various pathological conditions associated with advanced aging. Until 2016 - when the results of previous human studies were reviewed - a vast majority of the studies had dealt with age-related neurological diseases, like cerebrovascular and neurodegenerative diseases, multiple sclerosis, as well as some other common diseases in elderly such as migraine, traumatic brain injury and post-traumatic stress disorder, chronic hepatitis and nephrotic syndrome. The aim of this review is to summarize the old and the new results and highlight those 'classical' and emerging clinical fields in which PACAP may become subject to further investigation as a diagnostic and/or prognostic biomarker in age-related diseases.

Genomic Aging, Clonal Hematopoiesis, and Cardiovascular Disease

Chronologic age is the dominant risk factor for coronary artery disease but the features of aging promoting coronary artery disease are poorly understood. Advances in human genetics and population-based genetic profiling of blood cells have uncovered the surprising role of age-related subclinical leukemogenic mutations in blood cells, termed "clonal hematopoiesis of indeterminate potential," in coronary artery disease. Such mutations typically occur in DNMT3A, TET2, ASXL1, and JAK2. Murine and human studies prioritize the role of key inflammatory pathways linking clonal hematopoiesis with coronary artery disease. Increasingly larger, longitudinal, multiomics analyses are enabling further dissection into mechanistic insights. These observations expand the genetic architecture of coronary artery disease, now linking hallmark features of hematologic neoplasia with a much more common cardiovascular condition. Implications of these studies include the prospect of novel precision medicine paradigms for coronary artery disease.

Risk factors for clonal hematopoiesis of indeterminate potential and mosaic chromosomal alterations

Clonal hematopoiesis of indeterminate potential (CHIP) and mosaic chromosomal alterations (mCAs) of the autosomes, X, and Y chromosomes are aging-related somatic mutations detectable in peripheral blood. The presence of these acquired mutations predisposes otherwise healthy adults to increased risk of several chronic aging-related conditions including hematologic cancers, atherosclerotic cardiovascular diseases, other inflammatory conditions, and mortality. While the public health impact and disease associations of these blood-derived somatic mutations continue to expand, the inherited, behavioral/lifestyle, environmental risk factors and comorbid conditions that influence their occurrence and progression have been less well characterized. Age is the strongest risk factor for all types of CHIP and mCAs. CHIP and mCAs are generally more common in individuals of European than non-European ancestry. Evidence for a genetic predisposition has been strongest for mosaic loss of Y chromosome in men. Genome-wide association studies have recently begun to identify common and rare germline genetic variants associated with CHIP and mCAs. These loci include genes involving cell cycle regulation, cell proliferation/survival, hematopoietic progenitor cell regulation, DNA damage repair, and telomere maintenance. Some loci, such as TERT, ATM, TP53, CHEK2, and TCL1A, have overlapping associations with different types of CHIP, mCAs, and cancer predisposition. Various environmental or co-morbid contexts associated with presence or expansion of specific CHIP or mCA mutations are beginning to be elucidated, such as cigarette smoking, diet, cancer chemotherapy, particulate matter, and premature menopause. Further characterization of the germline genetic and environmental correlates of CHIP/mCAs may inform our ability to modify their progression and ultimately reduce the risk and burden of chronic diseases associated with these clonal somatic phenomena.

Clonal Hematopoiesis of Indeterminate Potential in Patients with Solid Tumor Malignancies

Clonal hematopoiesis of indeterminate potential (CHIP) refers to the expansion of cells of hematopoietic lineage that carry acquired somatic alterations associated with hematologic malignancies. The most commonly altered genes giving rise to CHIP are DNMT3A, TET2, and ASXL1. However, advanced sequencing technologies have resulted in highly sensitive detection of clonal hematopoiesis beyond these known driver genes. In practice, CHIP is commonly identified as an incidental finding in liquid and tissue biopsies of patients with solid tumors. CHIP can have broad clinical consequences, given its association with hematologic malignancies and nonmalignant diseases. CHIP can also interfere with next-generation DNA sequencing results, so clinicians should pay careful attention when these results are being used to guide therapy. Future research is needed to determine how solid tumor malignancies and their treatments alter the progression of CHIP, and in turn, how CHIP might be used to improve treatment selection and outcomes for patients with solid tumors.

Sleep exerts lasting effects on hematopoietic stem cell function and diversity

A sleepless night may feel awful in its aftermath, but sleep's revitalizing powers are substantial, perpetuating the idea that convalescent sleep is a consequence-free physiological reset. Although recent studies have shown that catch-up sleep insufficiently neutralizes the negative effects of sleep debt, the mechanisms that control prolonged effects of sleep disruption are not understood. Here, we show that sleep interruption restructures the epigenome of hematopoietic stem and progenitor cells (HSPCs) and increases their proliferation, thus reducing hematopoietic clonal diversity through accelerated genetic drift. Sleep fragmentation exerts a lasting influence on the HSPC epigenome, skewing commitment toward a myeloid fate and priming cells for exaggerated inflammatory bursts. Combining hematopoietic clonal tracking with mathematical modeling, we infer that sleep preserves clonal diversity by limiting neutral drift. In humans, sleep restriction alters the HSPC epigenome and activates hematopoiesis. These findings show that sleep slows decay of the hematopoietic system by calibrating the hematopoietic epigenome, constraining inflammatory output, and maintaining clonal diversity.

Clonal hematopoiesis of indeterminate potential, DNA methylation, and risk for coronary artery disease

Age-related changes to the genome-wide DNA methylation (DNAm) pattern observed in blood are well-documented. Clonal hematopoiesis of indeterminate potential (CHIP), characterized by the age-related acquisition and expansion of leukemogenic mutations in hematopoietic stem cells (HSCs), is associated with blood cancer and coronary artery disease (CAD). Epigenetic regulators DNMT3A and TET2 are the two most frequently mutated CHIP genes. Here, we present results from an epigenome-wide association study for CHIP in 582 Cardiovascular Health Study (CHS) participants, with replication in 2655 Atherosclerosis Risk in Communities (ARIC) Study participants. We show that DNMT3A and TET2 CHIP have distinct and directionally opposing genome-wide DNAm association patterns consistent with their regulatory roles, albeit both promoting self-renewal of HSCs. Mendelian randomization analyses indicate that a subset of DNAm alterations associated with these two leading CHIP genes may promote the risk for CAD.

Clonal hematopoiesis of indeterminate potential and cardiovascular disease

Age is the most important risk factor for cardiovascular disease and appears to be more than a marker of cumulative exposure to other risk factors such as dyslipidemia and hypertension. With aging, genetic mutations occur that are not present in our germline DNA, observed as somatic mosaicism. Hematopoietic stem cells have an increased chance of developing mosaicism because they are highly proliferative, and mutations with survival benefits can establish clonal populations. Age-related clonal hematopoiesis resulting from somatic mutations was first described ∼25 years ago. The subset of clonal hematopoiesis in which a driver mutation with variant allele frequency of at least 2% occurs in a gene implicated in hematologic malignancies but in the absence of known hematologic malignancy or other clonal disorder is termed clonal hematopoiesis of indeterminate potential (CHIP). Large-scale exome-sequencing projects have recently enabled the study of CHIP frequency, gene-specific analyses, and longitudinal clinical consequences of CHIP, including an observed increased risk for cardiovascular disease. Animal models provide insight into the mechanisms by which CHIP increases cardiovascular disease risk, and combined animal, clinical, and epidemiological data suggest therapeutic implications for CHIP in cardiovascular disease prevention.

Genome-wide analyses of 200,453 individuals yield new insights into the causes and consequences of clonal hematopoiesis

Clonal hematopoiesis (CH), the clonal expansion of a blood stem cell and its progeny driven by somatic driver mutations, affects over a third of people, yet remains poorly understood. Here we analyze genetic data from 200,453 UK Biobank participants to map the landscape of inherited predisposition to CH, increasing the number of germline associations with CH in European-ancestry populations from 4 to 14. Genes at new loci implicate DNA damage repair (PARP1, ATM, CHEK2), hematopoietic stem cell migration/homing (CD164) and myeloid oncogenesis (SETBP1). Several associations were CH-subtype-specific including variants at TCL1A and CD164 that had opposite associations with DNMT3A- versus TET2-mutant CH, the two most common CH subtypes, proposing key roles for these two loci in CH development. Mendelian randomization analyses showed that smoking and longer leukocyte telomere length are causal risk factors for CH and that genetic predisposition to CH increases risks of myeloproliferative neoplasia, nonhematological malignancies, atrial fibrillation and blood epigenetic ageing.