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Introduction: Atrial fibrillation (AF) is a common arrhythmia associated with aging. Many known risk factors are associated with AF, but many senior individuals do not develop AF despite having multiple risk factors. This finding suggests that other factors may be involved in AF onset. This study aimed to identify upregulated genes in the peripheral blood and left atrium of patients with AF. These genes may serve as potential biomarkers to predict AF onset risk and its complications. Methods: Gene expression data were analyzed from blood (n = 3) and left atrial samples (n = 15) of patients with AF and sinus rhythm. We evaluated the significant genes identified using p value analysis of weighted average difference to confirm their rankings. We created figures for the genes using GeneMANIA and performed a functional analysis using Cytoscape3.10.1. Hub and bottleneck genes were identified based on degree and betweenness centrality. We used reference expression (RefEx) to confirm the organs in which the extracted genes were expressed. Heatmaps and Gene ontology term evaluation were performed to further elucidate the biological functions of the genes. Results: We identified 12 upregulated genes (CAST, ASAH1, MAFB, VCAN, DDIT4, FTL, HEXB, PROS1, BNIP3L, PABPC1, YBX3, and S100A6) in both the blood and left atrium of patients with AF. We analyzed the gene functions using GeneMANIA and Cytoscape. The identified genes were involved in a variety of pathways, including lysosomal function and lipid and sphingolipid catabolism. Next, we investigated whether the 12 identified genes identified were systemically expressed or had high organ specificity. Finally, RefEx was used to analyze the gene expression levels in various tissues. Four genes, FTL, ASAH1, S100A6, and PABPC1, were highly expressed in the normal heart tissue. Finally, we evaluated the expression levels of the 12 genes in the blood of patients with AF using a heatmap. Our findings suggest that the 12 genes identified in this study, especially the lysosome-related genes (FTL and ASAH1), may be involved in AF pathogenesis. Conclusion: Lysosome-related genes may be important to understand the AF pathophysiology and to develop AF-related future studies. Plain Language Summary: Atrial fibrillation (AF) is an aging disorder and risk factor for patients with cardiovascular disease, which is the leading cause of mortality among senior individuals. Despite intensive research, the prevalence of AF is rising in the senior population, and identifying new therapeutic targets and prognostic markers is therefore critically important. Our research focuses on the lysosomal pathway. Lysosome mediates protein degradation, which is activated in the heart and blood. We conducted bioinformatics analyses of publicly available databases to identify the upregulated genes and pathways in patients with AF. We analyzed gene expression data from blood and left atrium samples of patients with AF and sinus rhythm. We identified 12 upregulated genes in the blood and left atrium in patients with AF. These genes are mainly involved in lysosome-related functions. These findings suggest that the 12 genes identified in this study, especially lysosome-related genes, may be involved in the AF pathogenesis. Lysosome-related genes are important for cellular homeostasis and waste degradation. Therefore, their upregulation in patients with AF may play a role in disease development and progression. Our study proposes new insights into the underlying molecular mechanisms of AF and identifies potential biomarkers for predicting the AF onset risk or complications. [ABSTRACT FROM AUTHOR]

Objectives: We conducted a text mining analysis of 40 years of literature on cardiac aging from PubMed to investigate the current understanding on cardiac aging and its mechanisms. This study aimed to embody what most researchers consider cardiac aging to be. Methods: We used multiple text mining and machine learning tools to extract important information from a large amount of text. Results: Analysis revealed that the terms most frequently associated with cardiac aging include "diastolic," "hypertrophy," "fibrosis," "apoptosis," "mitochondrial," "oxidative," and "autophagy." These terms suggest that cardiac aging is characterized by mitochondrial dysfunction, oxidative stress, and impairment of autophagy, especially mitophagy. We also revealed an increase in the frequency of occurrence of "autophagy" in recent years, suggesting that research on autophagy has made a breakthrough in the field of cardiac aging. Additionally, the frequency of occurrence of "mitophagy" has increased significantly since 2019, suggesting that mitophagy is an important factor in cardiac aging. Conclusions: Cardiac aging is a complex process that involves mitochondrial dysfunction, oxidative stress, and impairment of autophagy, especially mitophagy. Further research is warranted to elucidate the mechanisms of cardiac aging and develop strategies to mitigate its detrimental effects. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Although atrial fibrillation is a prevalent condition, it is crucial to recognize that it can be effectively addressed by identifying the underlying disease and not merely assuming that it is caused by aging. [ABSTRACT FROM AUTHOR]

Aim: Cardiac aging, which causes cardiac diastolic dysfunction, frequently occurs in older people. The role of autophagy in cardiac aging is the subject of intensive research. Autophagy comprises steps called the autophagosome formation and autophagosome–lysosome fusion. Caloric restriction (CR) is the gold standard used to induce autophagosome formation, and autophagosome–lysosome fusion is reduced by aging. However, few studies are available that survey and compare signaling during CR (autophagosome formation induced status) and old (potentially autophagosome–lysosome fusion‐reduced status). Here we aimed to identify the rate‐limiting step of autophagic disorders during cardiac aging. Methods: We employed bioinformatics to analyze publicly available DNA microarray datasets. The first dataset compared the hearts of young and old C57BL6 mice (OLD). The second dataset compared the hearts of young C57BL6 mice fed a normal diet with those of young C57BL6 mice subjected to CR. Results: We analyzed OLD‐upregulated genes that were significantly associated with the Gene Ontogeny term "Autophagy," indicating that autophagic genes were upregulated in OLD mice. The autophagy‐related gene Atg5 and Atg5‐related genes were upregulated in OLD and CR mice. The identified hub and bottleneck genes are autophagic autophagosome formation suppressors such as Sirt2, Ilk and Islr, as well as the autophagosome–lysosome fusion inducer Snapin. Conclusions: Autophagosome formation genes were upregulated in aging mice subjected to CR, indicating that an upregulated autophagosome formation is not a change specific to cardiac aging. However, autophagosome–lysosome fusion genes, particularly the lysosome transportation‐related gene Snapin, were downregulated in aging, indicating that autophagosome–lysosome fusion may cause autophagic disorders in cardiac aging. Geriatr Gerontol Int 2021; 21: 108–115. [ABSTRACT FROM AUTHOR]

Introduction: The prevalence of atrial fibrillation (AF) increases with age. Although most AF cases are caused by irregular electrical impulses near the pulmonary vein, not all elderly individuals develop AF. Moreover, risk factors such as hypertension and diabetes do not always lead to AF, even in severe conditions such as pneumonia. We aimed to examine iron kinetics, including ferritin, in patients with AF and individuals in normal sinus rhythm (NSR) using peripheral blood samples., Methods: This case-control study included 178 patients who visited the outpatient clinic of a cardiovascular and arrhythmia specialist at the National Center for Geriatrics and Gerontology between August and October 2023. Patients with missing iron-related blood tests and those with pacemaker implantation were excluded. Iron parameters (ferritin, free iron, transferrin saturation) were compared between AF (n = 53) and NSR (n = 125) groups., Results: The AF group had higher log brain natriuretic peptide (BNP) levels, indicating increased cardiac load (AF 2.18 vs. NSR 1.53). However, there were no significant differences in iron parameters between the AF and NSR groups. After matching for age, sex, and coronary artery disease, the AF group showed an increasing trend in ferritin and a decreasing trend in free iron with BNP elevation, suggesting chronic inflammation. In contrast, the NSR group showed no significant changes in iron parameters with BNP elevation., Conclusion: Patients with AF are more likely to have elevated ferritin levels and decreased free iron levels during cardiac overload. Thus, they are more likely to present with chronic inflammation associated with cardiac overload in AF. Future studies should investigate the mechanisms underlying this phenomenon and its implications for AF treatment., (© 2024 S. Karger AG, Basel.)

Aim: The coronavirus disease (COVID-19) pandemic has caused significant disruptions in various aspects of daily life. The Japanese Government declared a state of emergency in April 2020, which resulted in reduced physical activity. This study investigated the impact of these lifestyle changes by generation among outpatients with cardiovascular disease (CVD)., Methods: In autumn 2020, we conducted a questionnaire survey of 1,156 CVD outpatients who visited the Department of Cardiology at our institution. The survey collected data on physical activities and changes in daily behaviors over the course of the COVID-19 pandemic. Participants were classified into 3 age groups: middle-aged (n=114, ≤64 years old), semi-old (n=330, aged 65-74 years old), and old (n=712, ≥75 years old). The number of steps per day and sedentary time per day were compared between autumn 2019 and 2020, over the course of the pandemic., Results: In autumn 2020, the number of steps per day was significantly decreased and sedentary time significantly increased in all age groups compared to the pre-pandemic levels. However, there were no significant differences in the extent of changes in steps per day or sedentary time over the study period across all age groups. Regarding changes in daily behaviors, only the old-age group reported a decline in volunteering and reduced utilization of daycare services., Conclusions: The COVID-19 pandemic has resulted in changes in daily activities and lifestyles across all age groups. Because lifestyle patterns differ across generations, it may be necessary to implement age-specific interventions and procedures.