Cardioneuroablation (CNA) is proposed as a promising therapy for patients with sinoatrial node dysfunction (SND) that is mediated by excessive vagal tone. However, a series of urgent questions about CNA remain unanswered. From December 2020 to March 2022, six patients with symptomatic SND who underwent CNA were summarized in this report. Sequential CNA targeting Ao-SVC GP, PMLGP, RAGP, and LSGP was performed in patients, guided by fractionated intracardiac electrograms and dynamically evaluated by extracardiac vagal stimulation (ECVS). The results showed that Ao-SVC GP ablation led to a significant increase in heart rate (HR) and the elimination of sinus arrest evoked by ECVS, while the vagal responses of atrial ventricular block were eliminated by the ablation of PMLGP and LSGP. Post-procedure HR increased up to 64–86% of the maximum HR of an atropine test at baseline. The median HR from Holter monitoring increased from 52.8 ± 2.1 bpm at baseline to 73.0 ± 10.4 bpm after the procedure (p = 0.012) and to 71.3 ± 10.1 bpm at the six-month follow-up (p = 0.011). Bradycardia-related symptoms disappeared in all patients at the six-month follow-up. This case series reveals the feasibility of using the ECVS-assisted sequential CNA technique and indicates the critical role of ECVS in dynamically evaluating the impact of sequential CNA on the vagal control of SAN and AVN.

Background: Heart failure with preserved ejection fraction (HFpEF) is a multifaceted syndrome with high morbidity and mortality. Empagliflozin, an SGLT2 (sodium–glucose cotransporter 2) inhibitor, reduces adverse events in patients with HFpEF regardless of glycemic control. However, the precise cardioprotective mechanisms of SGLT2 inhibitor in HFpEF remain underexplored. Methods and Results: A “2‐hit” mouse model of HFpEF was developed via the high‐fat diet combined with N ^ω ‐nitro‐L‐arginine methyl ester. Male C57BL/6N mice were assigned to either a control group (n=10) or an HFpEF group (n=20), with the latter receiving empagliflozin (10 mg/kg per day, n=10) or vehicle (n=10) for 8 weeks. Cardiac function, hypertrophy, and fibrosis were evaluated by physiological, biochemical, and histological measurements. Mechanistic analysis, including RNA sequencing, Western blotting, and immunohistochemistry, was conducted. In vitro, H9c2 cardiomyocytes were exposed to angiotensin II and palmitate, followed by empagliflozin treatment. In vivo, empagliflozin treatment improved body weight, blood pressure, glucose tolerance, and reduced cardiac hypertrophy, fibrosis, and diastolic dysfunction in HFpEF mice. Mechanistic analysis revealed that empagliflozin modulated the AMPK (AMP‐activated protein kinase)/mTORC1 (mammalian target of rapamycin complex 1)/autophagy signaling pathway. Specifically, empagliflozin restored the autophagy markers (Beclin1 and LC3‐II [microtubule‐associated protein 1 light chain 3]) and altered the phosphorylation of AMPK, mTOR, and p70S6K (ribosomal protein S6 kinase beta‐1). Inhibition of AMPK or autophagy nullified the antihypertrophic effect of empagliflozin, underscoring the dependence on the AMPK/mTORC1/autophagy pathway. Conclusions: Empagliflozin effectively ameliorates cardiac remodeling and diastolic dysfunction in HFpEF by enhancing autophagy via the AMPK/mTORC1 pathway. These findings elucidate the direct cardioprotective mechanisms of empagliflozin and suggest potential therapeutic molecular targets for HFpEF.

Cardiac fibroblasts are a major source of cardiac fibrosis during heart repair processes in various heart diseases. Although it has been shown that cardiac fibroblasts become senescent in response to heart injury, it is unknown how the senescence of cardiac fibroblasts is regulated in vivo. Gata4, a cardiogenic transcription factor essential for heart development, is also expressed in cardiac fibroblasts. However, it remains elusive about the role of Gata4 in cardiac fibroblasts. To define the role of Gata4 in cardiac fibroblasts, we generated cardiac fibroblast-specific Gata4 knockout mice by cross-breeding Tcf21-MerCreMer mice with Gata4^fl/fl mice. Using this mouse model, we could genetically ablate Gata4 in Tcf21 positive cardiac fibroblasts in an inducible manner upon tamoxifen administration. We found that cardiac fibroblast-specific deletion of Gata4 spontaneously induces senescence in cardiac fibroblasts in vivo and in vitro. We also found that Gata4 expression in both cardiomyocytes and non-myocytes significantly decreases in the aged heart. Interestingly, when αMHC-MerCreMer mice were bred with Gata4^fl/fl mice to generate cardiomyocyte-specific Gata4 knockout mice, no senescent cells were detected in the hearts. Taken together, our results demonstrate that Gata4 deficiency in cardiac fibroblasts activates a program of cellular senescence, suggesting a novel molecular mechanism of cardiac fibroblast senescence.

Skeletal muscle regeneration declines with age despite the persistence of satellite cells (muscle stem cells, MuSCs), suggesting that regenerative impairment reflects functional dysregulation rather than MuSC depletion. Increasing evidence identifies early MuSC activation during the immediate post-injury period as a stress-sensitive, rate-limiting transition that is particularly vulnerable in aged muscle. Aged MuSCs exhibit elevated stress responses and reduced membrane remodeling capacity, accompanied by weakened activation-associated transcriptional induction. In contrast, proliferative and differentiation programs remain largely intact once activation is successfully initiated. These findings underscore that impaired coordination during early activation contributes to long-term regenerative decline in aging. Within this framework, MG53 (tripartite motif–containing protein 72, TRIM72), a muscle-enriched TRIM family E3 ubiquitin ligase originally identified as a mediator of sarcolemmal membrane repair, may also function as a stress-responsive regulator that stabilizes the early activation environment. Rather than directly determining cell fate, MG53 is proposed to facilitate activation by mitigating stress-associated membrane disruption and maintaining programmatic coordination under age-related physiological constraints. Most mechanistic evidence derives from rodent models, and direct validation in human aging muscle remains limited. These observations suggest that targeting early activation, rather than simply increasing proliferation, may better preserve regenerative capacity in aging skeletal muscle.

Skeletal muscle regeneration declines with age despite the persistence of satellite cells, indicating that regenerative impairment reflects functional dysregulation rather than stem cell loss. Increasing evidence identifies early satellite cell activation as a stress-sensitive, rate-limiting checkpoint that is preferentially disrupted in aged muscle. Integrative analyses indicate that aged satellite cells exhibit elevated stress programs and reduced membrane remodeling capacity, accompanied by weakened activa-tion-associated transcriptional signatures, while proliferative and differentiation pro-grams remain relatively accessible in successfully activated cells. This imbalance is consistent with impaired activation fidelity, in which early instability drives compen-satory downstream responses at the expense of long-term self-renewal. Within this framework, MG53 (TRIM72) is positioned beyond its canonical role in myofiber mem-brane repair as a permissive, stress-responsive regulator that stabilizes the early acti-vation environment. Rather than directly specifying cell fate, MG53 is proposed to support early activation by limiting stress-associated membrane disruption and main-taining coordination of the activation program under age-related constraints. These ob-servations suggest that restoring activation quality, rather than amplifying proliferation, may represent a more durable strategy to preserve regenerative capacity in aging skeletal muscle.

Genetic diseases can be caused by monogenic diseases, which result from a single gene mutation in the DNA sequence. Many innovative approaches have been developed to cure monogenic genetic diseases, namely by genome editing. A specific type of genomic editing, prime editing, has the potential advantage to edit the human genome without requiring double‐strand breaks or donor DNA templates for editing. Additionally, prime editing does not require a precisely positioned protospacer adjacent motif (PAM) sequence, which offers flexible target and more precise genomic editing. Here we detail a novel construction of a prime editing extended guide RNA (pegRNA) to target mutated leptin receptors in B6.BKS(D)‐Leprdb/J mice (db/db mice). The pegRNA was then injected into the flexor digitorum brevis (FDB) muscle of db/db mice to demonstrate in vivo efficacy, which resulted in pegRNA mediated base transversion at endogenous base transversion. Genomic DNA sequencing confirmed that prime editing could correct the mutation of leptin receptor gene in db/db mice. Furthermore, prime editing treated skeletal muscle exhibited enhanced leptin receptor signals. Thus, the current study showed in vivo efficacy of prime editing to correct mutant protein and rescue the physiology associated with functional protein.