Aging-Related Decline of Autophagy in Patients with Atrial Fibrillation-A Post Hoc Analysis of the ATHERO-AF Study

Oroxin B Resembles Bisoprolol in Attenuating Beta1-Adrenergic Receptor Autoantibody-Induced Atrial Remodelling via the PTEN/AKT/mTOR Signalling Pathway

Beta1-adrenergic receptor autoantibodies (β1-AAbs) promote atrial remodelling and ultimately lead to the development of atrial fibrillation (AF). Oroxin B is a natural flavonoid glycoside with a variety of biological activities, including anti-inflammatory and autophagy-promoting effects, and has therapeutic benefits for a variety of diseases. The aim of this study was to investigate the potential therapeutic role of Oroxin B in the development of β1-AAb-induced atrial fibrillation and to elucidate the underlying mechanisms involved. We established a rat model of β1-AAb-induced atrial fibrillation via active immunisation. The first stage was divided into three groups: the control group, the β1-AAb group and the β1-AAb + bisoprolol group. The second stage was divided into three groups: the control group, the β1-AAb group and the β1-AAb + Oroxin B group. Serum levels of β1-AAbs, atrial tissue levels of cyclic monophosphate (cAMP), atrial electrophysiological parameters, cardiac structure and function, mitochondrial structure, autophagy levels, cardiomyocyte apoptosis and myocardial fibrosis were examined. The results showed that bisoprolol, a β1-blocker, improved β1-AAb-induced atrial electrical remodelling, reduced atrial collagen deposition, ameliorated the increase in LAD and regulated the balance of autophagy and apoptosis in atrial myocytes through the PTEN/AKT/mTOR signalling pathway. Oroxin B, a PTEN agonist, can improve the impairment of autophagy homeostasis and apoptosis in atrial tissue by activating the PTEN/AKT/mTOR signalling pathway, thereby improving atrial structure and electrical remodelling. Moreover, Oroxin B may play a therapeutic role in β1AAb-induced atrial fibrillation. In conclusion, our results demonstrate the potential therapeutic role of Oroxin B in β1AAb-induced atrial fibrillation and the underlying mechanisms, suggesting that Oroxin B may be an effective antiarrhythmic medication.

Differences in Iron Kinetics during Cardiac Load between Patients with Atrial Fibrillation and Those with Sinus Rhythm

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.

Non-Genomic Hallmarks of Aging-The Review

Aging is a natural, gradual, and inevitable process associated with a series of changes at the molecular, cellular, and tissue levels that can lead to an increased risk of many diseases, including cancer. The most significant changes at the genomic level (DNA damage, telomere shortening, epigenetic changes) and non-genomic changes are referred to as hallmarks of aging. The hallmarks of aging and cancer are intertwined. Many studies have focused on genomic hallmarks, but non-genomic hallmarks are also important and may additionally cause genomic damage and increase the expression of genomic hallmarks. Understanding the non-genomic hallmarks of aging and cancer, and how they are intertwined, may lead to the development of approaches that could influence these hallmarks and thus function not only to slow aging but also to prevent cancer. In this review, we focus on non-genomic changes. We discuss cell senescence, disruption of proteostasis, deregualation of nutrient sensing, dysregulation of immune system function, intercellular communication, mitochondrial dysfunction, stem cell exhaustion and dysbiosis.

Autophagy-related proteins: Potential diagnostic and prognostic biomarkers of aging-related diseases

Autophagy plays a key role in cellular, tissue and organismal homeostasis and in the production of the energy load needed at critical times during development and in response to nutrient shortage. Autophagy is generally considered as a pro-survival mechanism, although its deregulation has been linked to non-apoptotic cell death. Autophagy efficiency declines with age, thus contributing to many different pathophysiological conditions, such as cancer, cardiomyopathy, diabetes, liver disease, autoimmune diseases, infections, and neurodegeneration. Accordingly, it has been proposed that the maintenance of a proper autophagic activity contributes to the extension of the lifespan in different organisms. A better understanding of the interplay between autophagy and risk of age-related pathologies is important to propose nutritional and life-style habits favouring disease prevention as well as possible clinical applications aimed at promoting long-term health.

Dual Pathway Inhibition with Rivaroxaban and Aspirin Reduces Inflammatory Biomarkers in Atherosclerosis

ABSTRACT

Dual pathway inhibition (DPI) with low-dose rivaroxaban and aspirin in patients with coronary artery disease (CAD) and/or peripheral artery disease (PAD) reduces the occurrence of cardiovascular (CV) events; however, the underlying mechanisms explaining these latter CV benefits are not clearly understood. Our explorative observational study aimed to evaluate the effect of dual pathway inhibition on plasma inflammation and coagulation markers among real-world patients with CAD and/or PAD. We prospectively included all consecutive patients with an established diagnosis of CAD and/or PAD treated with aspirin 100 mg once daily (OD) and rivaroxaban 2.5 mg twice daily (TD). Clinical evaluation and laboratory analyses, including hemoglobin, renal function (creatinine, urea, and cystatin-C), coagulation markers (INR and aPTT), inflammation markers (IL-6, CRP, lipoprotein-associated phospholipase A2, and copeptin), and growth differentiation factor-15 (GDF-15), were conducted at baseline, before starting treatment, and at 4 and 24 weeks after study drug administration. Fifty-four consecutive patients (mean age 66 ± 7 years; male 83%) who completed the 6-month follow-up were included. At 24-week follow-up, a statistically significant reduction in IL-6 serum levels [4.6 (3.5-6.5) vs. 3.4 (2.4-4.3) pg/mL ; P = 0.0001] and fibrinogen [336 (290-390) vs. 310 (275-364) mg/dL; P = 0.04] was shown; moreover, a significant increase in GDF-15 serum level [1309 (974-1961) vs. 1538 (1286-2913) pg/mL; P = 0.002] was observed. Hemoglobin, renal function, and cardiovascular homeostasis biomarkers remain stable over the time. The anti-Xa activity at both [0.005 (0-0.02) vs. 0.2 (0.1-0.34); P < 0.0001) significantly increased. The dual pathway inhibitions with low-dose rivaroxaban and aspirin in patients with CAD and/or PAD were associated with the reduction of inflammation biomarkers.