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Old trees are remarkable for their ability to endure for centuries or even millennia, acting as recordkeepers of historical climate and custodians of genetic diversity. The secret to their longevity has long been a subject of fascination. Despite the challenges associated with studying old trees, such as massive size, slow growth rate, long lifespan and often remote habitat, accumulating studies have investigated the mechanisms underlying tree aging and longevity over the past decade. The recent publication of high‐quality genomes of long‐lived tree species, coupled with research on stem cell function and secondary metabolites in longevity, has brought us closer to unlocking the secrets of arboreal longevity. This review provides an overview of the global distribution of old trees and examines the environmental and anthropogenic factors that shape their presence. We summarize the contributions of physiological characteristics, stem cell activity, and immune system responses to their extraordinary longevity. We also explore the genetic and epigenetic 'longevity code', which consists of resistance and defense genes, DNA repair genes and patterns of DNA methylation modification. Further, we highlight key areas for future research that could enhance our understanding of the mechanisms underlying tree longevity. Summary statement: The mechanism of tree longevity is highly complex, including modular growth and aging of the organism, maintenance of stem cell activity, expansion of resistance genes, accumulation of resistance substances, DNA repair and epigenetic modification. [ABSTRACT FROM AUTHOR]

Higher serum cholesterol levels have been associated with an increased risk of dry eye disease (DED). The relationship between statin (HMG‐CoA reductase inhibitor) use and DED in patients with hyperlipidemia remains unclear. To investigate the association between statin use and the risk of DED in patients with hyperlipidemia, we conducted a population‐based retrospective cohort study utilizing data from Taiwan's Longitudinal Generation Tracking Database. Patients were categorized into statin users and nonusers, with a 5‐year follow‐up period. The study identified patients with newly diagnosed hyperlipidemia, excluding those with prior DED diagnoses. Matching and adjustments for covariates resulted in 41,931 individuals in each group. Patients receiving statin therapy were compared with those unexposed. Cumulative exposure doses were also evaluated to assess dose–response relationships. The primary outcome was the incidence of DED diagnosed during the follow‐up period. Cox proportional hazards regression models estimated the risk of DED, and conditional logistic regression analyzed the dose–response effect of statin exposure. Among 41,931 matched pairs, statin users exhibited a slightly increased risk of developing DED compared with nonusers (adjusted hazard ratio, 1.06; 95% CI, 1.02–1.11; p < 0.01). However, no dose–response relationship was observed between statin exposure and DED risk. Statin use among patients with hyperlipidemia is associated with a marginally higher risk of DED. These findings underscore the importance of regular eye examinations in this patient population to facilitate early detection and management of DED. [ABSTRACT FROM AUTHOR]

Ginkgo biloba leaves contain abundant flavonoids, and flavonoid accumulation is affected by age. MicroRNAs (miRNAs) play an important role in the plant aging pathway. However, the miRNAs involved in flavonoid biosynthesis related to age in G. biloba have rarely been studied. In this study, we compared 1-, 4-, and 7-year-old ginkgo seedings and found a significant decrease in the content of quercetin, kaempferol, and total flavonol aglycones with age. We then profiled miRNAs in G. biloba through high-throughput sequencing on leaf samples of 1-, 4-, and 7-year-old ginkgo. GO and KEGG analyses suggest that photosynthesis and hormones may influence the flavonoid content. In particular, we identified 29 miRNAs related to the aging pathway according to their miRNA expression patterns. Correlation analysis of age-related miRNAs and major flavonoid compounds screened 17 vital miRNAs, including miRN79, miR535a, miR166a, miR171a, and miR396. Interactive miRNA-transcription factor network analysis suggested that the pivotal miRN79-DELLA and miR535a-SPL modules may be involved in flavonoid biosynthesis and aging pathways through post-transcriptional regulation. Our findings provide insights into the age-dependent regulatory roles of miRNAs in flavonoid biosynthesis. [ABSTRACT FROM AUTHOR]