Wang, Yong

Background Disruption in rest‐activity rhythm (RAR) is an emerging risk factor for cardiovascular disease (CVD) and mortality, but the strength of evidence is unclear. Therefore, we conducted a systematic review and meta‐analysis to assess associations between RAR characteristics and cardiovascular disease incidence or prevalence, cardiovascular mortality, and all‐cause mortality. Methods A systematic search was conducted in PubMed, Web of Science, Cochrane Library, and Embase for cohort or cross‐sectional studies published up to August 2025. The exposure variables were nonparametric RAR parameters, including interdaily stability (describing day‐to‐day stability of the RAR), intradaily variability (a measure of RAR fragmentation), and relative amplitude (indicating robustness or strength of the RAR). The primary outcomes were cardiovascular mortality and all‐cause mortality. The secondary outcomes included cardiovascular disease prevalence and incidence. Results Seven studies involving 109 365 participants were included. Pooled results showed that higher intradaily variability was associated with a significantly increased risk of all‐cause mortality (hazard ratio [HR], 1.05 [95% CI, 1.02–1.09]) and cardiovascular disease prevalence (odds ratio, 1.73 [95% CI, 1.21–2.47]). Lower relative amplitude was significantly associated with higher cardiovascular mortality (HR, 1.50 [95% CI, 1.13–1.98]) and all‐cause mortality (HR, 1.46 [95% CI, 1.27–1.68]). Interdaily stability showed no significant associations with any outcome. Conclusions Measures of disrupted rest‐activity rhythms were associated with increased cardiovascular mortality, and all‐cause mortality. These findings support using RAR metrics as early, noninvasive risk indicators. Future work should investigate whether appropriately timed physical activity and sleep, as well as other interventions targeting RAR can mitigate cardiovascular risk.

Rationale: Anthracycline-induced cardiotoxicity (AIC) is a major side effect that limits the use of anthracyclines as effective chemotherapeutics. No mechanism-based therapy is available when cardiac function deteriorates. Objective: We aim to elucidate the dynamic autophagic defects in AIC and to identify a mechanism-based therapy via both genetic and pharmacological studies. Method and Results: Through phenotyping an adult AIC zebrafish model, we detected a biphasic response in autophagy: activation in the early stage and suppression in the later phase that is characterized by a decline in cardiac function. We conducted conditional genetic studies with atg7 , which encodes a rate-limiting autophagy core protein, and found that atg7 overexpression leads to therapeutic effects in the late phase but deleterious effects in the early phase of adult AIC. We then assessed the therapeutic effects of 37 Food and Drug Administration–approved autophagy activators using an embryonic AIC zebrafish model and identified spironolactone, pravastatin, and minoxidil as top-ranking drugs. We demonstrated the therapeutic efficacy of these Food and Drug Administration–approved autophagy activators in the adult AIC model and confirmed that these drugs exert therapeutic effects in the late phase but not in the early AIC phase. Finally, we demonstrated that the time-dependent therapeutic effects are conserved in a mouse AIC model and that spironolactone and rapamycin activated autophagy in an Atg7-dependent fashion. Conclusions: Our findings suggest that atg7-based autophagy activation is an effective therapeutic avenue to reversing the decline in cardiac function in AIC, highlighting the time-dependent nature of autophagy-based therapy.

RXRA is an endothelial- and early stage–predominant therapeutic target for treating anthracycline-induced cardiotoxicity.

ABSTRACT The adult zebrafish is an emerging vertebrate model for studying human cardiomyopathies; however, whether the simple zebrafish heart can model different subtypes of cardiomyopathies, such as dilated cardiomyopathy (DCM), remains elusive. Here, we generated and characterized an inherited DCM model in adult zebrafish and used this model to search for therapeutic strategies. We employed transcription activator-like effector nuclease (TALEN) genome editing technology to generate frame-shift mutants for the zebrafish ortholog of human BCL2-associated athanogene 3 (BAG3), an established DCM-causative gene. As in mammals, the zebrafish bag3 homozygous mutant (bag3e2/e2) exhibited aberrant proteostasis, as indicated by impaired autophagy flux and elevated ubiquitinated protein aggregation. Through comprehensive phenotyping analysis of the mutant, we identified phenotypic traits that resembled DCM phenotypes in mammals, including cardiac chamber enlargement, reduced ejection fraction characterized by increased end-systolic volume/body weight (ESV/BW), and reduced contractile myofibril activation kinetics. Nonbiased transcriptome analysis identified the hyperactivation of the mechanistic target of rapamycin (mTOR) signaling in bag3e2/e2 mutant hearts. Further genetic studies showed that mtorxu015/+, an mTOR haploinsufficiency mutant, repaired abnormal proteostasis, improved cardiac function and rescued the survival of the bag3e2/e2 mutant. This study established the bag3e2/e2 mutant as a DCM model in adult zebrafish and suggested mtor as a candidate therapeutic target gene for BAG3 cardiomyopathy.