Fight Aging!

Control over the structure of nuclear DNA is critical to both gene expression and interactions between DNA damage and DNA repair systems. Most of us are by now at least passingly familiar with the concept of the chromosomes of nuclear DNA existing as a mix of (a) spooled and tightly packaged regions known as heterochromatin, where gene sequences are hidden from transcriptional machinery and genes are thus not expressed, versus (b) unspooled regions where transcription can take place, the gene sequences read to allow assembly of corresponding RNA molecules. Epigenetic decorations to DNA and supporting molecules drive a constant shift between spooled and unspooled structures. This necessary regulation of structure and function all changes for the worse with advancing age for reasons that are incompletely understood.

There is a lot more to DNA structure than just this, however. For example, the intricate regulation of nuclear DNA structure incorporates the presence of double-strand breaks known as DNA gaps, distinct from the harmful DNA double strand breaks that occur as a form of damage. These DNA gaps are thought to reduce potentially damage-inducing stress forces, but this may or may not be their primary function. Researchers have observed that the number of these DNA gaps declines with age, and have speculated that this change may produce harm. In today's open access paper, researchers provide fairly direct evidence for this proposition via use of a gene therapy that directly induces DNA gap formation in aged non-human primates. The researchers observe a range of improvements in biomarkers of health following treatment, suggesting that more DNA gaps leads to improved cell and tissue function; all in all, quite an interesting outcome.

Box A of HMGB1 plasmid reverses the age-related changes in the plasma proteomic profile of perimenopausal monkeys

A characteristic feature of aging is the accumulation of DNA damage, which plays a significant role in the deterioration of cellular function. The sustained destruction of DNA and the subsequent activation or failure of the DNA-damage response (DDR) are pivotal in the aging process, often leading to detrimental cellular outcomes such as senescence, apoptosis, and telomere shortening. Maintaining DNA integrity is crucial for cell viability. One mechanism employed by cells to ensure this integrity involves the dynamic regulation of DNA structures, often observed as DNA gaps, known as youth-DNA-gaps. These gaps are believed to minimize mechanical stress and torsion forces within the DNA structure, thereby protecting it from damage. Interestingly, the number of these physiological DNA gaps typically is reduced in yeast, rats, and human cells as they age, as well as in chemically-induced senescent cells.

High Mobility Group Box 1 (HMGB1) protein has emerged as a key molecule involved in various biological processes highly relevant to aging, including inflammation, DNA repair, and cell senescence. The Box A domain of HMGB1 is a highly conserved DNA-binding domain crucial for modulating HMGB1's biological functions. Box A is known to bind DNA and interact with other proteins, acting as a molecular regulator that influences the formation of DNA gaps to enhance DNA integrity and protection. Growing evidence suggests that Box A-induced DNA gaps may reverse aging characteristics in vivo and in vitro, having been shown to inhibit liver fibrosis and improve aging brain functions in aged rat models. Furthermore, Box A can enhance stemness, suggesting a role in improving stem cell activity compromised by illness and aging.

This study investigates the potential role of the Box A domain HMGB1 in modulating age-related changes. We utilized a label-free quantitative proteomic technique to analyze the plasma proteome of three female adult and eight female perimenopausal cynomolgus macaques (Macaca fascicularis), with the perimenopausal group receiving an intravenous administration of the Box A plasmid. Proteomic analysis revealed differential expressions in proteins primarily associated with stress response, immune regulation, lipid transport, and cellular homeostasis following Box A plasmid intervention. Notably, the expression levels of key proteins, such as apolipoprotein E (APOE) and sex hormone-binding globulin (SHBG), showed a reversal effect, restoring levels closer to those observed in the younger, adult monkeys. These findings highlight the potential of the Box A of HMGB1 plasmid as a therapeutic candidate to mitigate age-related proteomic alterations, offering a novel avenue for targeted interventions in aging and associated diseases.

The burden of lingering senescent cells grows with age in tissues throughout the body. Cells enter the senescent state constantly, but the pace of clearance of senescent cells by the immune system falters with advancing age. Senescent cells secrete a mix of pro-inflammatory, pro-growth signals that are disruptive to tissue structure and function when sustained for the long term. Analysis of circulating molecules in a blood sample can in principle be used to measure the body-wide burden of senescent cells, though no strong consensus approach has emerged yet from the various methods demonstrated in recent years. Here, find another contender for that consensus approach, where researchers use proteomic assessment of blood samples to build a score based on the strength of senescent cell signaling, and find that this score correlates with mortality risk.

The accumulation of senescent cells is a recognized hallmark of biological aging and is associated with the onset of multiple chronic medical conditions. Senescent cells exhibit a distinct secretory profile, known as the senescence-associated secretory phenotype (SASP), which can propagate cellular senescence to neighboring and distant tissues. Measuring SASP factors in blood serves as a practical proxy for cellular senescence burden and may help track disease states and intervention outcomes.

We developed and validated a composite SASP Score by integrating large-scale population proteomics data with a semi-supervised deep learning framework. The analytical workflow included: (1) selection of biologically curated SASP proteins; (2) development of a Guided autoencoder with Transformer (GAET) model using data from the UK Biobank Pharma Proteomics Project (UKB-PPP); (3) internal evaluation and association analyses within the UK Biobank; and (4) external validation and longitudinal assessment in an independent randomized clinical trial cohort.

The deep learning-based SASP Score was a strong, independent predictor of mortality risk and incident serious, chronic medical conditions (e.g., dementia, COPD, myocardial infarction, stroke). In an independent cohort, multimodal exercise significantly changed the SASP Score trajectory over 18 months.

Link: https://doi.org/10.64898/2026.03.20.26348913

Excessive, constant inflammation in response to aspects of one's own cellular biochemistry is a feature of both autoimmune disease and aging. While transient inflammation is necessary for effective regeneration and defense against pathogens, constant unresolved inflammatory signaling is destructive to tissue structure and function. It is a major component of the pathology of common age-related conditions. The challenge in addressing this is that unwanted inflammation and desirable inflammation both involve the same molecular signals and points of control. To date, therapies that reduce chronic inflammation do so via crude blockade of signals or mechanisms, with the side effect of reduced immune capability, a reduction in the normal immune response when it is needed. The research community is slowly making progress towards finding points of distinction, however, approaches to intervention that have greater effects on unwanted inflammation than they do on the normal immune response. One such line of work is noted here, focused on autoimmunity.

Current autoimmune disease treatments like hydroxychloroquine work by broadly blocking endosomes, the compartments inside cells where incoming materials are sorted and processed, including molecules that trigger immune responses. While effective, this approach can lead to significant side effects - including gastrointestinal problems and, less commonly, vision damage-causing a significant number of patients to stop treatment.

Researchers focused on two proteins, Munc13-4 and syntaxin 7, that must bind together for immune sensors called Toll-like receptors (TLRs) to activate inside endosomes. This "molecular handshake" plays a key role in detecting the foreign DNA and RNA from invaders like viruses and bacteria. However, in autoimmune diseases, TLRs become overactive, detecting self-nucleic acids, for example, from neutrophil-extracellular traps, and trigger chronic, damaging inflammation even without a real threat.

The team screened roughly 32,000 compounds and identified molecules that specifically block the Munc13-4-syntaxin 7 interaction without disrupting other cellular functions. Because Munc13-4 is found mainly in immune cells, the compounds offer a targeted way to calm inflammation. "Most treatments for autoimmune diseases manage symptoms; they don't change the underlying course of the disease. What's exciting about this approach is its potential to be disease-modifying: targeting the specific molecular machinery that drives inflammation, rather than broadly suppressing the immune system."

The most potent compound, ENDO12, reduced inflammation in animal models that were also given a TLR-activating molecule. Blood levels of inflammatory markers - including immune system activators IL-6 and IFN-γ, and the enzyme myeloperoxidase - dropped significantly in those that were treated. Crucially, ENDO12 did not impair the animal models' ability to fight a real viral infection: they showed a normal antiviral immune response when exposed to a virus. This selectivity addresses a major concern with immunosuppressive drugs: that dampening inflammation might leave patients vulnerable to infections.

Link: https://www.scripps.edu/news-and-events/press-room/2026/20260406-catz-endotollins.html

A sizable body of evidence indicates that transposons contribute to degenerative aging. Transposons of various categories are DNA sequences that code for molecular machinery capable of writing copies of the original DNA into other locations in the genome. They are largely the remnants of ancient retroviral infections, altered and degraded over evolutionary time, while likely remaining an important mechanism of mutational change for future evolution. Transposons are suppressed in youth, the nuclear DNA sequences spooled and hidden from transcriptional machinery, but one of the noteworthy aspects of aging is a loss of epigenetic control over nuclear DNA structure and thus over gene expression. Stretches of DNA containing transposons unspool and become accessible to transcriptional machinery. Transposon expression produces molecules that are sufficiently virus-like for evolved defenses to react with inflammatory signaling, while the haphazard insertion of transposon sequences is a form of DNA damage, breaking genes.

Just like retroviruses, retrotransposons require reverse transcription to function. That part of the research and development community focused on HIV, human immunodeficiency virus, has spent decades developing ever better means of sabotaging reverse transcription. In today's open access paper, researchers report on their investigation of the effects of such antiretroviral drugs on measures of biological age. The researchers made use of data and samples originating from pharmacokinetic clinical studies of combinations of antiretroviral drugs in healthy volunteers. One combination of drugs did reduce measures of biological age, while the other did not. This suggests that there is indeed something interesting here, but that the fine details matter when it comes to the implementation of transposon suppression.

An FDA-Approved Tenofovir Alafenamide-Based Antiretroviral Therapy Reduces Biological Age in Healthy Adults: First Human Proof-of-Concept for Retrotransposon-Targeted Gerotherapeutics

Nearly half of the human genome (∼45%) is composed of transposable elements (TEs). Aging is accompanied by a progressive erosion of epigenetic silencing that permits the transcriptional reactivation of these TEs, particularly retrotransposons such as LINE-1 and endogenous retroviruses. In young somatic cells, these elements are maintained in a transcriptionally inert state by DNA methylation, heterochromatin, and KRAB-ZFP/KAP1 surveillance. However, with age the fidelity of these mechanisms declines, and retrotransposon-derived transcripts and cytoplasmic DNA accumulate. This age-dependent retroelement reactivation is now recognized as a proximal driver of biological aging hallmarks including a senescence-associated secretory phenotype (SASP) and age-related tissue dysfunction.

The dependence of retroelements on reverse transcription has made nucleoside reverse transcriptase inhibitors (NRTIs), which were developed and licensed for HIV treatment and prevention, attractive candidate gerotherapeutics. For instance, a retrospective analysis of longitudinal aging intervention studies identified antiretroviral therapy as one of the most consistent interventions associated with reductions across 16 epigenetic clocks. Early mechanistic work showed that multiple NRTIs including 3TC (lamivudine), tenofovir disoproxil fumarate (TDF), stavudine, and zidovudine can directly suppress human LINE-1 retrotransposition in cell-based reporter systems. Consistent with this, 3TC (lamivudine) blunted LINE-1 cDNA-triggered type I interferon signaling and components of the SASP in senescent human cells and reduced age-associated inflammatory signatures across multiple tissues in aged mice.

Here we evaluated DNA methylation-based measures of biological aging in healthy people without HIV (aged 18-50) using samples from two separate randomized, directly observed dosing pharmacokinetic studies of FDA-approved NRTI regimens containing emtricitabine / tenofovir-alafenamide (FTC/TAF; 200 mg/25 mg) or FTC / tenofovir-disoproxil fumarate (FTC/TDF; 200 mg/300 mg) for 12 weeks.

In the FTC/TAF study (N=36), epigenetic aging measures based on DNA methylation (DNAm) profiling decreased over follow-up, including DunedinPACE (-0.061) and PhenoAge (-6.33), with concordant reductions across additional systems-specific epigenetic clocks including those estimating brain aging. DNAm-based proxies of inflammatory biomarkers also declined, with significant reductions in epigenetic IL-6 (-0.058) and a trend toward reduced C-reactive protein (-0.231). In contrast, the FTC/TDF study (N=43) showed no significant changes across epigenetic clocks and proxies. These findings are consistent with TAF's more favorable cellular pharmacology compared with TDF and support gerotherapeutic effects of FTC/TAF.

Prospective placebo-controlled studies are warranted that integrate clinical pharmacology, direct transposable element readouts, and prespecified geroscience and DNA methylation-based aging endpoints.

There are apparently a great many people who at least intermittently use psilocybin. Interestingly, regular dosing with psilocybin has been shown to modestly extend life in mice, but it is likely that only a subset of human users approach the frequency of dosing used in the mouse studies. Finding those humans is ever the challenge, particularly if one wants to study long-term effects on aging. Here, a researcher takes an initial stab at comparing the longevity of psilocybin users with non-users based on publicly available information, but the sample size is so small that it isn't surprising to see a lack of useful results. The study is more interesting as a way to provoke (a) awareness of the evidence for psilocybin to interact with mechanisms of aging, and (b) some thought on what sort of study design would be both practical and useful.

Researchers have reported that psilocybin promotes resilience and extends lifespan in aged mice. This work garnered considerable media attention, with claims that psychedelics might also extend human lifespan. Psychedelics influence longevity-related pathways in rodents such as glucocorticoid receptor signaling and mitochondrial stress tolerance. In light of these findings and in search of some evidence that psychedelics can indeed extend human lifespan, we examined historical mortality patterns of psychedelic personalities (researchers and advocates who had documented, mostly self-claimed, psychedelic use) and compared this group to biomedical researchers (cancer and aging).

Using publicly available records, we identified individuals who died between 2010 and 2025: (i) psychedelic personalities with documented personal use (n = 11), (ii) cancer researchers (n = 12), and (iii) aging researchers (n = 5). Deaths before age 60 were excluded. Conditional life expectancy at age 40 for their birth cohorts (≈73-76 years, US/UK data) was used as a baseline. All three groups lived well beyond population averages, consistent with the survival advantage of highly educated professionals. Crucially, the psychedelic personalities did not outlive their biomedical peers.

Thus, while researchers have provided compelling mechanistic data in mice, translation to humans requires dose-specific and longitudinal studies to identify whether psychedelics such as psilocybin do indeed have some role in extending lifespan.

Link: https://doi.org/10.1038/s41514-026-00380-y

It is well established that females and males in mammalian (and many other) species exhibit meaningfully different trajectories of health and mortality in later life. It is also well established, at least in mice, that many of the interventions demonstrated to modestly slow aging have meaningfully different outcomes in males versus females. The question of why these differences exist has no satisfactory answer at the present time, however. There are a great many theories and potential contributions, but no data that concretely establishes the important mechanisms and relative sizes of these contributions to the overall effect.

The burden of aging is not shared equally between the sexes, as lifespan and healthspan differ between males and females. Lifespan, the length of time in which an organism is alive, is related to but distinct from healthspan, which is the length of time an organism is free of disease and disability. Women live longer than men in most countries, but women also experience more disease and disability than men.

While scientists seek interventions to increase both healthspan and lifespan, considering sex as a biological variable is imperative to ensure treatments will work optimally in both men and women, or to develop sex-specific interventions. Here, we review dietary, genetic, environmental, behavioral, and pharmacological interventions that increase lifespan in a sexually dimorphic manner in laboratory rodents, including the mouse which is the is most widely used mammalian model system in the aging field.

While sex differences in life history traits have long been of interest to evolutionary biologists, a cellular and molecular understanding of how these traits influence lifespan remains understudied. Starting from fertilization, differences in chromosome complement and hormone levels drive further morphological and behavioral differences. Crucial aspects of female biology, including the role of X chromosome regulation, the role of gonadal hormones, and the role of ovarian health, remain understudied in the context of aging interventions. Whether differences in response to interventions is due sex-specific differences in baseline lifespan, or differences in sexually dimorphic characteristics such as body size, adiposity, metabolism, or even gonadal hormone or chromosome status remains unknown.

Link: https://doi.org/10.1016/j.arr.2026.103123

In the US alone, new strains of influenza reliably emerge to kill tens of thousands of older people every year, hundreds of thousands in a bad year. The research and development community has yet to fully develop and deploy any of the possible approaches that might effectively shut down viral infections, such as descendants of the DRACO technology, and the aged immune system becomes ever less able to resist and control infections of all sorts. In later life, the immune system also becomes more inflammatory, more vulnerable to runaway inflammation during infection that leads to sepsis. Further, other aspects of aging make organs and tissues less able to resist the stresses that result from severe infection and accompanying inflammation.

One of the ways in which influenza infection and accompanying inflammation kills older people is by provoking what is known as a major adverse cardiovascular event, meaning a heart attack or stroke, that would otherwise not have occurred. One of the ways that influenza vaccination can help to reduce mortality is by preventing evident infection and all of its consequences. Another, as shown in today's open access paper, is by reducing the severity of the infection, the stress placed upon organ systems, and thus the risk of fatal heart attack and stroke. There are many good reasons to maintain a vaccination schedule in late life, even given the reduced capacity of the aged immune system, and this is one of them.

Influenza vaccination attenuates acute myocardial infarction and stroke risk following influenza infection: a register-based, self-controlled case series study, Denmark, 2014 to 2025

Influenza infection can trigger acute cardiovascular events through short-lived systemic inflammation that favours a pro-thrombotic state and destabilises vulnerable atherosclerotic plaques. Self-controlled case series studies, which compare event rates within individuals during prespecified risk time windows against their own baseline time, have consistently shown transient increases in cardiovascular risk after laboratory-confirmed influenza. A Canadian study reported a sixfold increase in acute myocardial infarction risk during the first 7 days after positive test results (incidence rate ratio (IRR) = 6.05); estimates from Spain and the Netherlands are similar. Studies employing finer temporal resolution have further characterised the risk profile, indicating that peak incidence increases within 3 days, then tapers back within 2-4 weeks.

Among mounting evidence suggesting that influenza vaccination reduces cardiovascular risk, a recent meta-analysis of randomised controlled trials estimated 32% lower risk. Two successive self-controlled case-series studies in the United Kingdom demonstrated a 20-23% reduced incidence for both acute myocardial infarction and stroke. In particular, the second study reported no evidence of sex-specific differences, and effects were slightly stronger among people vaccinated early in the influenza season. A meta-analysis including these same two studies provided further evidence of the protective effect of vaccination (pooled IRR = 0.84 for acute myocardial infarction).

In this self-controlled case series study in Denmark spanning 2014 to 2025, PCR-confirmed influenza was followed by a sharp, transient rise in the first-ever hospitalisations for acute myocardial infarction and stroke. Risk concentrated in the first week, peaking within 3 days, and declined back to baseline by 2 weeks. Prior influenza vaccination was associated with a significantly lower excess risk. This temporal profile aligns with studied mechanisms. Influenza infection has been shown to precipitate atherogenesis and has been epidemiologically linked to acute myocardial infarction and stroke in adults 40 years and older.

Vaccination can plausibly mitigate these effects by priming adaptive immunity and reducing viral replication, thereby dampening systemic inflammatory peaks. By vaccination status, the adjusted IRRs for cardiovascular events in this study were 4.7 and 2.4 for unvaccinated and vaccinated episodes, respectively. To our knowledge, this is the first study to show statistically significant attenuation of post-influenza cardiovascular risk by vaccination. A Canadian study observed similar results but possibly lacked statistical power to confirm them.

Researchers here describe a novel approach to encourage greater regeneration in heart tissue following the injury and lost function incurred during a heart attack. Their work falls into the growing category of practical gene therapies in which a small amount of easily accessible tissue, such as fat or muscle, is transfected to form a factory that generates and releases a beneficial circulating protein. Only a low dose of gene therapy vector is needed, and all of the present challenges in broader delivery of gene therapy are bypassed. The scope of possible uses is restricted to situations in which benefits can be derived from increased amounts of a specific protein in circulation, but this is still a large enough set of possibilities to support a broad industry.

During the first days of life, many mammals have a short-lived ability to regenerate heart muscle cells. A hormone called atrial natriuretic peptide (ANP) plays a key role by encouraging the growth of new blood vessels, calming inflammation, and reducing the formation of scars. As an individual ages, the amount of ANP in their bodies decreases substantially, and the regenerative capacity observed in newborn hearts largely disappears by adulthood. Researchers have understood the potential of ANP for decades, but it's difficult to use as a conventional drug because it begins breaking down after just a few minutes in the body.

Delivering a drug to the heart in a sustained and minimally invasive way is a significant challenge. Drugs aimed at organs such as the liver, lungs, or spleen can often accumulate naturally because of the unique features of their vascular systems and cellular uptake mechanisms. By contrast, the heart lacks such natural accumulation mechanisms, making efficient cardiac drug delivery more difficult. For researchers the solution was to stop trying to deliver the drug to the heart at all. Instead, they developed a two-phase approach that starts by creating a "prodrug" in skeletal muscle before transforming it into ANP within the heart itself.

The researchers designed RNA-lipid nanoparticles that encode Nppa, causing muscle cells in the thigh or arm to produce a molecule called pro-ANP. This molecule, which is not reactive in the body, circulates through the entire bloodstream. A specific enzyme, called Corin, transforms it into ANP. Corin is roughly 60 times more common in the heart than in other organs. In other words, the drug circulates until it reaches the one organ equipped to activate it. In lab experiments, a single injection significantly reduced scarring and improved heart function in small and large animals.

Link: https://www.engineering.columbia.edu/about/news/new-rna-therapy-could-help-heart-repair-itself

Researchers here review the landscape of immune aging with a particular focus on vulnerability to respiratory infections, such as influenza. As we age the immune system becomes ever less capable, the outcome of impaired manufacture of new immune cells, as well as issues that affect the internal workings of cells throughout the body, such as mitochondrial dysfunction and cellular senescence. At the same time the immune system becomes ever more active and inflammatory, a maladaptive reaction to forms of damage in cells and tissues. This creates a landscape in which infectious pathogens find it easier to overwhelm immune defenses, and in which inflammatory reactions to infection can readily become life-threatening, amplified by a dysfunctional immune system.

Every country around the globe is facing continuous growth in both the size and the proportion of older people; by 2050, the global population aged 60 years and above is projected to double, reaching approximately 2.1 billion people. As the population shifts towards older ages, new challenges are emerging, including increased healthcare demands. Among these challenges is "the destruction and remodelling of immune organ structure as well as innate and adaptive immune dysfunction with ageing", so-called immunosenescence, alongside inflammageing, a characteristic inflammatory state in which high levels of pro-inflammatory molecules are expressed. Both states predispose older adults to dysregulated immune responses and, inadvertently, to increased proportions of adverse outcomes, especially in the context of infections such as respiratory viral infections.

In this review, we examine the molecular and cellular pathophysiological mechanisms of immunosenescence and inflammageing that predispose older adults to increased morbidity and mortality from respiratory viral infections. We also outline the clinical implications of the ageing immune system, along with the most up-to-date evidence on possible biomarkers, preventative measures and treatment options aimed at mitigating the effects of immunosenescence on the vulnerability of older adults in respiratory viral infections.

Link: https://doi.org/10.1183/16000617.0248-2025

Cartilage tissue exhibits a relatively poor capacity for regeneration even in youth, but this capacity for maintenance and repair diminishes with age. There are thus some gains to be made in understanding why this happens and developing means of rejuvenation, but ultimately some form of regenerative medicine above and beyond natural degrees of healing will be needed in order to completely address the very prevalent joint issues that occur in later life and culminate in disabling degrees of cartilage loss and osteoarthritis. While this is widely studied, cartilage has so far proven to be a difficult tissue for the tissue engineering community to reproduce and manipulate. The load-bearing capacity and resilience necessary for its function in the body requires an accurate recreation of the complex extracellular matrix structure and cell behavior; pseudo-tissues of the sort that work well in tissue engineering for many organs are not good enough for cartilage.

Returning to the question of why cartilage tissue becomes less regenerative with age, in today's open access paper the authors turn their attention to macrophages. Macrophages of the innate immune system are present in large numbers in tissues throughout the body, and are deeply involved in the intricate processes that accompany tissue regeneration and tissue maintenance. Researchers have discovered a regulatory gene for macrophage behavior in cartilage that biases these cells towards pro-regenerative, anti-inflammatory patterns of behavior. Expression declines with age, however, and thus macrophages become increasingly inflammatory, leading to a reduced capacity for cartilage tissue maintenance and regeneration. Given the expression of this gene as a target, therapies can now be designed and tested to improve cartilage maintenance in older individuals.

Single-cell omics reveals arg-1 as a key regulator of age-dependent macrophage-mediated cartilage repair

Aging is a significant factor influencing the recovery capacity following cartilage injury, with notable differences observed between older and younger animals. Studies indicate that younger animals exhibit enhanced regenerative potential, including better cartilage repair and reduced inflammatory responses, compared to their older counterparts. This disparity may be attributed to age-related declines in stem cell activity, extracellular matrix synthesis, and immune function.

Macrophages play a multifaceted and context-dependent role in the pathogenesis of cartilage injury, contributing to both inflammatory progression and tissue repair. In the synovial microenvironment, macrophages exhibit remarkable plasticity, dynamically shifting between pro-inflammatory (M1-like) and anti-inflammatory (M2-like) phenotypes in response to local signals. While M1-polarized macrophages drive joint inflammation through the production of cytokines such as tumor necrosis factor-α (TNF-α), Interleukin-1β (IL-1β), and Interleukin-6 (IL-6), M2-like macrophages promote resolution of inflammation and tissue remodeling. However, this dichotomy is oversimplified, as single-cell studies reveal a spectrum of macrophage activation states in cartilage injury, with distinct subsets associated with disease severity and treatment response. Furthermore, synovial macrophages interact with fibroblasts, T cells, and osteoclasts, forming a complex cellular network that perpetuates joint destruction.

Our study employed single-cell RNA sequencing (scRNA-seq) to investigate the differential recovery capacity between young and aged animals following cartilage injury, explicitly addressing the inherent heterogeneity of immune cells within the joint. Through comprehensive profiling of joint tissues before and after injury, we aimed to identify age-dependent molecular mechanisms that govern post-injury recovery. Our analysis revealed that young animals exhibit a significantly higher proportion of anti-inflammatory macrophage subsets compared to aged counterparts, suggesting a link between specific immune cell states and enhanced tissue repair potential.

Further network analysis pinpointed Arg-1 (Arginase-1) as a central regulator within anti-inflammatory macrophages. Functional validation through in vivo and in vitro experiments demonstrated that Arg-1 overexpression inhibited inflammation and reactive oxygen species release in aged animals, partially rescuing their impaired recovery phenotype. These results not only elucidate the mechanistic basis for age-related disparities in cartilage injury recovery but also highlight Arg-1 as a novel therapeutic target to improve joint repair in elderly individuals. By integrating single-cell omics with mechanistic validation, this study provides critical insights into anti-inflammation macrophage in cartilage injury and offers a potential strategy to mitigate age-associated decline in tissue regeneration.

As the understanding of more recently discovered modes of programmed cell death are fleshed out, they receive greater attention from various groups focused on specific aspects of aging. In this review the programmed cell death mechanism is PANoptosis and the area of focus is the aging of the heart. Some means of preventing overly aggressive, maladaptive programmed cell death in the context of aging have performed fairly well in animal studies, but the details matter and progress towards useful therapies is ever slow and uncertain.

As the vital power organ of the human body, the health of the heart directly determines an individual's quality of life and longevity. With the accelerating global aging population, cardiac aging-related diseases have become a major public health threat. Although existing interventions (e.g., senolytics) can delay cardiac aging to some extent, their efficacy remains limited, necessitating the exploration of novel mechanisms to develop more effective therapeutic strategies.

In recent years, PANoptosis - an integrated cell death pathway - has emerged as a new research focus in cardiac aging. PANoptosis, a recently defined lytic cell death modality, integrates core molecular mechanisms of pyroptosis, apoptosis, and necroptosis into a dynamically regulated "death signaling network". As a unique programmed cell death paradigm, it transcends classical boundaries of these pathways by forming the PANoptosome complex, which orchestrates caspase family members. It may contribute to cardiac functional decline by accelerating cardiomyocyte loss, fibrosis, and chronic inflammation.

Targeting PANoptosis-based intervention strategies (e.g., gene editing, RNAi, combination therapy, and novel delivery systems) has demonstrated significant therapeutic potential, offering new preclinical avenues to delay or alleviate cardiac aging. This review summarizes the molecular mechanisms and roles of PANoptosis in cardiac aging, including its regulatory networks, key evidence driving cardiac aging, and targeted intervention strategies, thereby providing a theoretical foundation for developing PANoptosis-targeted therapies against cardiac aging.

Link: https://doi.org/10.3389/fcvm.2026.1759908

Does the correlation between late life vaccination and reduced risk of neurodegenerative conditions such as Alzheimer's disease exist because vaccination produces benefits such as reduced chronic inflammation via trained immunity, or because people who undergo vaccination tend to be more diligence in all matters relating to health? Mechanistic or behavioral, or both? And if both, how much of the overall observed effect size arises from each side? Researchers here find a way to obtain more insight into this correlation, as they show that different vaccine doses correlate with different degrees of reduced dementia risk. We should not expect this to be the case unless the outcome is driven by biological mechanisms resulting from vaccination.

Previous studies, including large cohort analyses comparing vaccinated and unvaccinated adults, suggest that routine immunizations such as inactivated influenza vaccines (IIVs) may reduce Alzheimer dementia (AD) risk. Whether AD risk differs after high-dose IIV (H-IIV) vs standard-dose IIV (S-IIV) remains unexamined. We hypothesized that AD risk would be lower among adults ≥65 years after H-IIV compared with S-IIV.

This retrospective cohort study analyzed data spanning 2014-2019 from IQVIA PharMetrics Plus for Academics, a US health care claims database. Eligible participants were ≥65 years with ≥2 years of continuous medical and pharmaceutical coverage and no previous diagnostic or pharmacotherapeutic indicators of cognitive impairment. Vaccinations were identified by name and Current Procedural Terminology codes. Participants were followed for up to 3 years postvaccination. Incident AD was defined using International Classification of Diseases codes and AD medication dispenses (cholinesterase inhibitors, memantine).

The H-IIV group included 120,775 unique participants (185,183 person-trials; mean age 74.4 ± 5.5 years; 57.3% female), and the S-IIV group included 44,022 participants (53,918 person-trials; mean age 73.0 ± 6.1; 56.4% female). H-IIV was associated with significantly lower AD risk during months 1-25 postvaccination. Further research is needed to clarify whether the observed difference reflects protection against influenza infection or non-infection-related mechanisms.

Link: https://doi.org/10.1212/WNL.0000000000214782

Transthyretin is one of a small number of proteins that can misfold and aggregate to cause pathology in tissues, primarily the cardiovascular system, but other organs as well once aggregation becomes very severe. Despite being a universal mechanism that operates in all older individuals, transthyretin amyloidosis is presently treated as a rare condition by the medical, development, and regulatory communities, because only the most severe cases exhibit evident symptoms that are easily diagnosed. Of those patients diagnosed, some have mutations that drive misfolding and aggregation of transthyretin, while some are simply the most severe examples of what is actually a prevalent issue in later later. Evidence from studies involving post-mortem examinations of tissues suggest that many very old people exhibit a degree of transthyretin amyloidosis that is in principle life-threatening, capable of contributing to cardiovascular mortality.

In recent years a number of drugs have been developed that act to reduce transthyretin misfolding and aggregation to a large enough degree to allow natural clearance mechanisms to catch up. As drugs go, they are fairly effective at achieving this outcome and have reasonable safety profiles. They are only used in the most severe, readily diagnosed patients, and thus regulated and priced as though transthyretin amyloidosis is a rare disease, however. Treatment is enormously expensive, as is usual for rare diseases, and will likely remain so until patent protection runs out and the drugs become generic. Before that point arrives there is all too little incentive for the drug owners to branch out and offer greater availability at a lower price point, regardless of the accumulating evidence for transthyretin amyloidosis to be a prevalent late life issue with meaningful effects on cardiovascular disease and mortality.

Nonetheless, it is worth keeping an eye on this part of the field as data accumulates from the long-term use of these transthyretin amyloidosis drugs. It provides an assessment of their value for a future of broadened generic use in the older population, once the market catches up with the science regarding implementation of that broader use. Today's open access paper is of interest in this regard, providing data on long-term use of acoramidis. Transthyretin exists in a dynamic equilibrium between monomer and tetramer forms, and only the monomer form contributes to amyloidosis. The better of the existing drugs, like acoramidis, act by stabilizing the tetramer form and thereby greatly reducing the size of the monomer pool. Clearly this works to reduce both amyloid and pathology.

Long-Term Durability of Acoramidis Efficacy in Transthyretin Amyloid Cardiomyopathy

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive disorder caused by destabilization of serum transthyretin (sTTR). Acoramidis, an approved therapy that achieves near-complete (≥90%) sTTR stabilization, demonstrated clinical benefit through month 30 in ATTRibute-CM, which was incremental through month 42 in the open-label extension (OLE); however, the longer-term durability of outcomes has not been reported.

This OLE of the ATTRibute-CM randomized clinical trial is an international, multicenter, ongoing OLE study. Data accumulated between October 2021 and April 2025 through month 24 of the OLE (month 54) are reported. Participants (aged 18-90 years) who completed ATTRibute-CM and met the OLE eligibility criteria were invited to enroll in the OLE. Data were analyzed from May 2025 through November 2025. All OLE participants received open-label oral acoramidis, 800 mg, twice daily. Acoramidis recipients from ATTRibute-CM continued therapy (continuous acoramidis) and placebo recipients switched to acoramidis (placebo to acoramidis).

The primary outcome was time to event for all-cause mortality (ACM), cardiovascular-related mortality (CVM), and first cardiovascular hospitalization (CVH), which was assessed for both groups. Biomarkers of disease progression (N-terminal pro-B-type natriuretic peptide [NT-proBNP]), sTTR, functional capacity (6-minute walk distance [6MWD]), and heart failure-related health status (Kansas City Cardiomyopathy Questionnaire-Overall Summary [KCCQ-OS] score) were analyzed.

In ATTRibute-CM, 632 participants were randomized to receive acoramidis (n = 421) or placebo (n = 211); mean (SD) age was 77.3 (6.6) years, and 62 participants (9.8%) were female. Overall, 389 participants enrolled in the OLE (263 in the continuous acoramidis group; 126 in the placebo-to-acoramidis group). Continuous acoramidis treatment reduced risks of ACM (hazard ratio [HR] 0.55) and CVM (HR 0.51) through month 54, with consistent efficacy across all prespecified subgroups. Continuous acoramidis reduced time to first CVH (HR 0.53) through month 54. Through month 54, continuous acoramidis stabilized increases in NT-proBNP, sustained higher sTTR levels, and stabilized KCCQ-OS score and 6MWD. Switching from placebo to acoramidis at month 30 was associated with stabilization of NT-proBNP and KCCQ-OS score and improvements in sTTR and 6MWD through month 54. No new long-term safety concerns were identified.

The capacity for neurons to regrow the axons that connect them is relatively limited. The tissue of large nerves, largely made up of axons, does not readily regenerate; the closer to the central nervous system one comes, the less the capacity for regrowth following injury. This is not the case for all species, and thus - in principle at least - there must be regulatory controls in cellular biochemistry that can be adjusted to encourage lesser degrees of obstructive scarring and greater regrowth of axons. Here, researchers report on one recently discovered way to enhance axon regrowth that works in both peripheral nerves and the spinal cord.

Axon regeneration is limited in the mammalian central nervous system. Neurons must balance stress responses with regenerative demands after axonal injury, but the mechanisms remain unclear. Here we identify aryl hydrocarbon receptor (AhR), a ligand-activated basic helix-loop-helix/PER-ARNT-SIM transcription factor, as a key regulator of this stress-growth switch. We show that ligand-mediated AhR signalling restrains axon growth, whereas neuronal deletion or pharmacological inhibition of AhR promotes axonal regeneration and functional recovery in both peripheral nerve and spinal cord injury models.

Mechanistic studies reveal that nerve injury induced AhR activation in dorsal root ganglion neurons enforces proteostasis and stress-response programs to preserve tissue integrity. By contrast, AhR ablation redirects the neuronal response towards elevated de novo translation and pro-growth signalling, enabling axon regeneration. This growth-promoting effect requires HIF1α, with shared transcriptional targets enriched for metabolic and regenerative pathways. Single-cell and epigenomic analyses further revealed that the AhR regulon engages the integrated stress response and DNA hydroxymethylation to rewire neuronal injury-response programs.

Together, our findings establish AhR as a neuronal brake on axon regeneration, integrating environmental sensing, protein homeostasis, and metabolic signalling to control the balance between stress adaptation and axonal repair.

Link: https://doi.org/10.1038/s41586-026-10295-z

New senolytic drugs to clear the accumulation of senescent cells in aged tissues are working their way into clinical trials at the usual slow pace for medical development, slowed even further by the poor biotech investment market of the past three years. Rubedo Life Science's first drug to target GPX4 mechanisms has now made it through a phase 1 trial; the company took the safer path of a topical application in skin conditions where cellular senescence is thought to be an important driver of pathology. That strategy looks promising based on the initial data. The largest challenge for biotech and pharmaceutical companies lies in convincing people to fund the first clinical trials in the first indication for their approach to drug development; given success, matters become easier after that point. So companies tend to initially pursue safer, more certain paths rather than those that may offer greater rewards in terms of addressing the burden of disease in the population.

Rubedo Life Sciences, focused on discovering and rapidly developing selective cellular rejuvenation medicines targeting aging cells, today announced preliminary results from a single-center, ascending-dose, randomized, double-blind, vehicle-controlled trial in patients with plaque psoriasis, atopic dermatitis, and skin aging (photo-aged skin). The recently completed Phase 1 clinical trial, conducted in the European Union, was designed to assess the safety, tolerability, clinical effects, plasma bioavailability, and pharmacodynamics of topical RLS-1496 - the first-ever GPX4 (selective glutathione peroxidase 4) modulator to be studied in human trials, and the first specifically targeting cellular rejuvenation, an area of great interest to the scientific community as a new therapeutic pathway. The study met its primary endpoint, with RLS-1496 also demonstrating early signs of efficacy.

In psoriasis patients an overall reduction in senescent cells seen with RLS-1496 in the mid- and high-dose cohorts. Some subjects treated with RLS-1496 had a reduction of senescent cells, which was associated with a reduction of inflammatory cytokines such as IL-19 and S100A7; this reduction was not seen in the vehicle cohort. An average 20% reduction in epidermal thickness was observed on histology in subjects treated with RLS-1496 for one month. A statistically significant relationship was seen between target engagement and improvement in clinical psoriasis severity.

In atopic dermatitis patients, even higher levels of target engagement and substantial clinical improvement were seen in atopic dermatitis subjects on RLS-1496. After one month of treatment, 25% of subjects on RLS-1496 had a ≥4-point change in pruritus (or itching) on the numeric rating scale (NRS); no vehicle subjects had a 4-point or more change on the NRS.

Early photo-aging data show a dose-dependent target engagement in non-lesional photo-aged skin. Histology, proteomics, and spatial transcriptomics indicate that collagen gene and protein expression increase with treatments over time, in particular, spatial transcriptomics shows an effect in dermal fibroblasts. Spatial transcriptomics show indication that senescence-associated secretory phenotype and inflammatory biomarkers decrease with treatments over time in keratinocytes.

Link: https://www.businesswire.com/news/home/20260326810310/en/Rubedo-Life-Sciences-Announces-Positive-Preliminary-Phase-1-Clinical-Trial-Results-for-Lead-Drug-Candidate-RLS-1496-in-Patients-with-Plaque-Psoriasis-Atopic-Dermatitis-and-Skin-Aging