Metabolic processes shape ageing and longevity at multiple levels. Emerging evidence shows that many of these processes are orchestrated within and between cellular organelles. Organelles function not only as metabolic reactors but also as signalling hubs, and their coordination plays crucial roles in maintaining cellular homeostasis and promoting organismal fitness. Rather than acting in isolation, organelles engage in dynamic crosstalk through membrane contact sites, metabolite exchange and signalling interplay. In recent years, organelles have been increasingly recognized as critical regulators of ageing and longevity. Here we summarize age-related organellar changes, highlight organelle-mediated intra- and intercellular signalling communication in lifespan and healthspan regulation, and discuss the active roles of organelles in microbiome-host interactions and transgenerational inheritance in regulating longevity. We further outline how longevity-promoting interventions influence organelles, and provide perspectives on how future technological advances may further accelerate progress in this emerging research topic.

Regulation of food intake in mammals is complex and controlled by an interplay between hedonic and homeostatic signals, including hormones like leptin, which senses fat storage and suppresses food intake. lack leptin and leptin receptors but still exhibit controlled eating. Here, we show that in eating can be regulated by a balance between saturated and monounsaturated fatty acids interacting with transcriptional pathways regulating lipid synthesis, c-AMP response element binding protein and AMP kinase. This effect is mediated at the endoplasmic reticulum through formation of phospholipids and activation of the IRE-1 sensor in the nervous system, which controls behavior through neuronal serotonin and the G-protein-coupled ligand/receptor pair PDF-1/PDFR-1. We show that this peptide/receptor pair may be an ancestral precursor of the whole family of GLP-1/GIP-related peptides and their receptors. Indeed, administration of a 37 amino acid peptide derived from PDF-1 resulted in a reduction in body weight and improved insulin sensitivity in mice. In worms, signaling through this pathway induced food-leaving behavior on concentrated food and roaming behavior on dispersed food, a state we have termed "food-apathy," paralleling pharmacologic effects of GLP-1/GIP-related peptides in humans. These findings highlight the potential evolutionary origin of this family of hormones and their receptors, and its link to metabolic and neuronal responses in control of feeding behavior.

The actin cytoskeleton is a fundamental and highly conserved structure that functions in diverse cellular processes, yet its direct contribution to organismal aging remains unclear. Here, we systematically interrogated how genetic and pharmacologic perturbations of actin structure and function influence lifespan and various hallmarks of aging in Caenorhabditis elegans. Whole-animal and tissue-specific knockdown of actin and key actin-binding proteins (ABPs) - arx-2 (Arp2/3), unc-60 (cofilin), and lev-11 (tropomyosin) - led to premature disruption of filament organization, reduced lifespan, and tissue-specific physiological defects. Bulk and single-nucleus RNA-sequencing revealed that ABP knockdowns elicited a strongly “aged” transcriptome. Actin dysfunction broadly exacerbated many age-associated phenotypes, including mitochondrial dysfunction, lipid dysregulation, loss of proteostasis, impaired autophagy, and intestinal barrier failure. Pharmacological destabilization with Latrunculin A mirrored genetic knockdowns, while mild stabilization with Jasplakinolide modestly extended lifespan, emphasizing that optimal and finely-tuned actin function is critical for healthy aging. Finally, analysis of human genome-wide association data revealed that common ACTB polymorphisms correlate with differences in age-related decline in gait speed, suggesting evolutionary conservation of actin’s role in healthy aging. Taken together, our results provide a comprehensive and publicly accessible resource that maps, for the first time, how actin integrity intersects with diverse aging pathways across tissues and scales. This descriptive framework is intended to enable future mechanistic discovery by offering a deep, unbiased dataset that can be integrated with emerging studies to define how actin dynamics contribute to aging.

Geroscience aims to target the aging process to extend healthspan. However, even isogenic individuals show heterogeneity in natural aging rate and responsiveness to pro-longevity interventions, limiting translational potential. Using RNAseq analysis of young, isogenic, subpopulations of Caenorhabditis elegans selected solely on the basis of the splicing pattern of an in vivo minigene reporter that is predictive of future life expectancy, we find a strong correlation in young animals between predicted life span and alternative splicing of mRNAs related to lipid metabolism. The activity of two RNA splicing factors, Reversed Polarity-1 (REPO-1) and Splicing Factor 1 (SFA-1), early in life is necessary for C. elegans response to specific longevity interventions and leads to context-specific changes to fat content that is mirrored by knockdown of their direct target POD-2/ACC1. Moreover, POD-2/ACC1 is required for the same longevity interventions as REPO-1/SFA-1. In addition, early inhibition of REPO-1 renders animals refractory to late onset suppression of the TORC1 pathway. Together, we propose that splicing factor activity establishes a cellular landscape early in life that enables responsiveness to specific longevity interventions and may explain variance in efficacy between individuals.

Microbiota-derived metabolites have emerged as key regulators of longevity. The metabolic activity of the gut microbiota, influenced by dietary components and ingested chemical compounds, profoundly impacts host fitness. While the benefits of dietary prebiotics are well-known, chemically targeting the gut microbiota to enhance host fitness remains largely unexplored. Here, we report a novel chemical approach to induce a pro-longevity bacterial metabolite in the host gut. We discovered that wild-type Escherichia coli strains overproduce colanic acids (CAs) when exposed to a low dose of cephaloridine, leading to an increased life span in the host organism Caenorhabditis elegans. In the mouse gut, oral administration of low-dose cephaloridine induced transcription of the capsular polysaccharide synthesis (cps) operon responsible for CA biosynthesis in commensal E. coli at 37 °C, and attenuated age-related metabolic changes. We also found that low-dose cephaloridine overcomes the temperature-dependent inhibition of CA biosynthesis and promotes its induction through a mechanism mediated by the membrane-bound histidine kinase ZraS, independently of cephaloridine's known antibiotic properties. Our work lays a foundation for microbiota-based therapeutics through chemical modulation of bacterial metabolism and highlights the promising potential of leveraging bacteria-targeting drugs in promoting host longevity.

Covalent inhibitors are an emerging class of therapeutics, but methods to comprehensively profile their binding kinetics and selectivity across the proteome have been limited. Here we introduce COOKIE-Pro (COvalent Occupancy KInetic Enrichment via Proteomics), an unbiased method for quantifying irreversible covalent inhibitor binding kinetics on a proteome-wide scale. COOKIE-Pro uses a two-step incubation process with mass spectrometry-based proteomics to determine k and K values for covalent inhibitors against both on-target and off-target proteins. We validated COOKIE-Pro using BTK inhibitors spebrutinib and ibrutinib, accurately reproducing known kinetic parameters and identifying both expected and unreported off-targets. The method revealed that spebrutinib has over 10-fold higher potency for TEC kinase compared to its intended target BTK. To demonstrate the method's utility for high-throughput screening, we applied a streamlined two-point strategy to a library of 16 covalent fragments. This approach successfully generated thousands of kinetic profiles, enabling the quantitative decoupling of intrinsic chemical reactivity from binding affinity at scale and validating the method's broad applicability. By providing a comprehensive view of covalent inhibitor binding across the proteome, COOKIE-Pro represents a powerful tool for optimizing the potency and selectivity of covalent drugs during preclinical development.

bioRxiv preprint: https://doi.org/10.1101/2025.06.19.660637

Epigenome is sensitive to metabolic inputs and crucial for aging. Lysosomes emerge as a signaling hub to sense metabolic cues and regulate longevity. We unveil that lysosomal metabolic pathways signal through the epigenome to regulate transgenerational longevity in Caenorhabditis elegans. We discovered that the induction of lysosomal lipid signaling and lysosomal AMP-activated protein kinase (AMPK), or the reduction of lysosomal mechanistic-target-of-rapamycin (mTOR) signaling, increases the expression of histone H3.3 variant and elevates H3K79 methylation, leading to lifespan extension across multiple generations. This transgenerational pro-longevity effect requires intestine-to-germline transportation of H3.3 and a germline-specific H3K79 methyltransferase, and can be recapitulated by overexpressing H3.3 or the H3K79 methyltransferase. This work uncovers a lysosome-epigenome signaling axis linking soma and germline to mediate the transgenerational inheritance of longevity.

bioRxiv preprint: https://www.biorxiv.org/content/early/2025/05/23/2025.05.21.652954

Fluorescence microscopy enables the visualization of cellular morphology, molecular distribution, ion distribution, and their dynamic behaviors during biological processes. Enhancing the signal-to-noise ratio (SNR) in fluorescence imaging improves the quantification accuracy and spatial resolution; however, achieving high SNR at fast image acquisition rates, which is often required to observe cellular dynamics, still remains a challenge. In this study, we developed a technique to rapidly freeze biological cells in milliseconds during optical microscopy observation. Compared to chemical fixation, rapid freezing provides rapid immobilization of samples while more effectively preserving the morphology and conditions of cells. This technique combines the advantages of both live-cell and cryofixation microscopy, i.e., temporal dynamics and high SNR snapshots of selected moments, and is demonstrated by fluorescence and Raman microscopy with high spatial resolution and quantification under low temperature conditions. Furthermore, we also demonstrated that intracellular calcium dynamics can be frozen rapidly and visualized using fluorescent ion indicators, suggesting that ion distribution and conformation of the probe molecules can be fixed both spatially and temporally. These results confirmed that our technique can time-deterministically suspend and visualize cellular dynamics while preserving molecular and ionic states, indicating the potential to provide detailed insights into sample dynamics with improved spatial resolution and temporal accuracy in observations.

Accumulating evidence indicates that biological aging can be accelerated by environmental exposures, collectively called the 'exposome'. The skin, as the largest and most exposed organ, can be viewed as a 'window' for the deep exploration of the exposome and its effects on systemic aging. The complex interplay across hallmarks of aging in the skin and systemic biological aging suggests that physiological processes associated with skin aging influence, and are influenced by, systemic hallmarks of aging. This bidirectional relationship provides potential avenues for the prevention of accelerated biological aging and the identification of therapeutic targets. We provide a review of the interactions between skin exposure, aging hallmarks in the skin and associated systemic changes, and their implications in treatment and disease. We also discuss key questions that need to be addressed to maintain skin and overall health, highlighting the need for the development of precise biomarkers and advanced skin models.