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Importance Typical cysteine-altering NOTCH3 ( NOTCH3 cys ) variants are highly prevalent (approximately 1 in 300 individuals) and are associated with a broad spectrum of small vessel disease (SVD), ranging from early-onset stroke and dementia (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy [CADASIL]) to nonpenetrance. A staging system that captures the full NOTCH3 -SVD severity spectrum is needed and currently lacking. Objective To design a simple disease severity staging system that captures the broad clinicoradiological NOTCH3 -SVD severity spectrum. Design, Setting, and Participants A cohort study was performed in which the NOTCH3 -SVD severity staging system was developed using a discovery cohort (2019-2020) and validated in independent international CADASIL cohorts (1999-2023) and the UK Biobank. Clinical and imaging data were collected from participants originating from 23 international CADASIL cohorts and from the UK Biobank. Eligibility criteria were presence of a NOTCH3 cys variant, availability of brain magnetic resonance imaging, and modified Rankin Scale score. The discovery cohort consisted of 195 NOTCH3 cys -positive cases from families with CADASIL; the validation set included 1713 NOTCH3 cys -positive cases from 15 countries. The UK Biobank cohort consisted of 101 NOTCH3 cys -positive individuals. Data from 2-year (2019-2023) and 18-year (1999-2017) follow-up studies were also analyzed. Data analysis was performed from July 2023 to August 2024. Main Outcomes and Measures Percentage of cases following the sequence of events of the NOTCH3 -SVD stages, and the association between the stages and ischemic stroke, intracerebral hemorrhage, global cognition, processing speed, brain volume, brain microstructural damage, and serum neurofilament light chain (NfL) level. Results The NOTCH3 -SVD staging system encompasses 9 disease stages or substages, ranging from stage 0 (premanifest stage) to stage 4B (end stage). Of all 1908 cases, which included 195 in the discovery cohort (mean [SD] age, 52.4 [12.2] years) and 1713 in the validation cohorts (mean [SD] age, 53.1 [13.0] years), 1789 (94%) followed the sequence of events defined by the NOTCH3 -SVD staging system. The NOTCH3 -SVD stages were associated with neuroimaging outcomes in the NOTCH3 cys -positive cases in the CADASIL cohorts and in the UK Biobank and with cognitive outcomes and serum NfL level in cases from the CADASIL cohorts. The NOTCH3 -SVD staging system captured disease progression and was associated with 18-year survival. Conclusions and Relevance The NOTCH3 -SVD staging system captures the full disease spectrum, from asymptomatic individuals with a NOTCH3 cys variant to patients with end-stage disease. The NOTCH3 -SVD staging system is a simple but effective tool for uniform disease staging in the clinic and in research.

Background: Patients with normal resting left ventricular ejection fraction (LVEF) without either coronary artery disease (CAD) or a hypertensive response can paradoxically develop reduced LVEF during exercise stress echocardiography (ESE). The clinical phenotype and outcomes of these patients is unknown. Hypothesis: Patients who paradoxically develop reduced LVEF during exercise may represent a sub-phenotype of heart failure with preserved LVEF (HFpEF). Aims: To describe the baseline characteristics and clinical outcomes of this unique patient population. Methods: Among all ESE performed between January 2003 and December 2022, patients without a hypertensive response to exercise and without CAD by angiogram within 90 days of ESE, who had a resting LVEF ≥50% with a ≥5% LVEF decrease during ESE were identified. All-cause mortality, HF hospitalization, and atrial fibrillation (AF) outcomes were assessed. Kaplan-Meier and Cox regression methods were used to analyze time-to-event outcomes. Results: Among 213,643 stress echocardiograms performed, 134 patients met eligibility criteria (Table 1). The mean age of the population was 66±10 years, 76% were women, and 16% had AF at baseline. Mean LVEF was 58±4% at rest and 43±4% at peak stress. Stress electrocardiogram met criteria for ischemia in 14%. The 10-year all-cause mortality risk was 12.9% (95% CI 5.5-20.3) with 10 (37%) of 27 deaths due to cancer (Figure 1, Panel A). The 10-year estimated risk of HF hospitalization was 17.6% (95% CI 9.0-26.2) (Figure 1, Panel B). Among 112 patients without AF at baseline, the 10-year risk of developing AF was 23.4% (95% CI 13.4-33.4). Conclusions: Patients with exercise-induced reduced LVEF in the absence of obstructive CAD have a high incidence of HF hospitalizations and AF. Given the preponderance of women, risk for AF, HF hospitalizations, and cancer-related deaths, the possibility that this condition is an early sub-phenotype of HFpEF should be investigated.

Background: Electrocardiography-based artificial intelligence (AI-ECG) validated models that detect cardiac disease are increasingly being applied in clinical practice. The utility of such tools to detect insidious cardiac disease in patients with normal baseline left ventricular ejection fraction (LVEF) who paradoxically develop reduced LVEF during exercise stress echocardiography (ESE), and do not have coronary artery disease (CAD) or hypertension, is unknown. Hypothesis: AI-ECG is useful to diagnose insidious cardiac disease and predict clinical outcomes in patients with exercise-induced cardiomyopathy. Aims: To assess the utility of AI ECG in patients with exercise-induced cardiomyopathy. Methods: Among all ESE performed between January 2003 and December 2022, patients without a hypertensive response to exercise and without CAD (confirmed by coronary angiography within 90 days after ESE), with resting LVEF ≥50% and a paradoxical ≥5% LVEF decrease during ESE were identified. A previously validated AI-ECG algorithm that predicts atrial fibrillation (AF), reduced LVEF, and cardiac amyloidosis (CA) was applied to the baseline ECG closest to the time of ESE. The predicted probability of AF, reduced LVEF, and CA if above the published thresholds, was determined. Results: There were 134 patients with exercise-induced cardiomyopathy who were identified. The mean age of this cohort was 66±10 years, 76% were women and 16% had AF at baseline. Mean LVEF was 58±4% at rest and 43±4% at peak stress. The median follow-up period was 6.8 years (IQR 3.0-12.2). Among patients without a baseline history of AF (n=112), AI-ECG identified 29% with a significant probability of AF, which was associated with a subsequent AF diagnosis at univariable analysis (HR 2.505, 95%CI 1.016-6.177, p=0.046). There were 10 patients with an AI-ECG prediction of reduced LVEF among whom 3 were subsequently hospitalized with HF. AI-ECG was positive for CA in 8 and 3 amongst these had subsequent HF hospitalizations (Table). Conclusions: Baseline AI-ECG may help predict subsequent AF and diagnose preclinical amyloid cardiomyopathy in patients who by resting echocardiography do not seem to have cardiac disease but with exercise develop reduced LVEF.

Case Description: A 68-year-old man with end-stage renal disease on dialysis, peripheral vascular disease with metatarsal amputations, atrial fibrillation and type 1 diabetes was admitted for foot osteomyelitis secondary to MSSA bacteremia. Transesophageal echocardiogram revealed mobile mitral valve vegetations up to 1.8cm on the atrial aspect of the posterior mitral valve leaflet which prolapsed through the mitral valve during diastole. Ejection fraction was 60% and there was trivial-mild mitral regurgitation without valvular destruction or peri-annular extension into the mitral annulus. MRI brain showed bilateral cerebral and cerebellar hemispheric infarcts, consistent with acute embolic stroke. He was at high risk for both recurrent embolism and operative mortality (STS risk score 51%) due to his comorbidities and risk of hemorrhagic conversion of stroke. After shared decision making, percutaneous aspiration of the mitral vegetation was performed with AngioVac (Fig). Cerebral embolism protection devices were deployed prior to AngioVac evacuation of the mass. There was no residual mitral regurgitation and only a small vegetation strand remained (Fig). Surgical pathology confirmed MSSA endocarditis. Blood cultures remained negative, and the patient did not suffer from recurrent embolic events. The patient underwent revision metatarsal amputation and was discharged with a 6-week course of IV cefazolin. Discussion: Infective endocarditis with high embolic risk is life-threatening and challenging to treat in patients with high surgical risk. We illustrate a case of percutaneous vegetation aspiration using the AngioVac device in our patient who suffered from embolic strokes due to MSSA mitral valve endocarditis. Meta-analyses have shown clinically successful debulking in 90% of cases, with 82% of patients able to clear bacteremia with AngioVac. Although most commonly used in right-sided lesions, percutaneous debulking of left-sided endocarditis with AngioVac and cerebral protection can be considered as a treatment strategy in select patients with prohibitive surgical risk.

Tubulin polyglutamylation is a posttranslational modification that occurs primarily along the axoneme of cilia. Defective axoneme polyglutamylation impairs cilia function and has been correlated with ciliopathies, including Joubert Syndrome (JBTS). However, the precise mechanisms regulating proper axoneme polyglutamylation remain vague. Here, we show that cyclin-dependent kinase 6 (CDK6), but not its paralog CDK4, localizes to the cilia base and suppresses axoneme polyglutamylation by phosphorylating RAB11 family interacting protein 5 (FIP5) at site S641, a critical regulator of cilia import of glutamylases. S641 phosphorylation disrupts the ciliary recruitment of FIP5 and its association with RAB11, thereby reducing the ciliary import of glutamylases. Encouragingly, the FDA-approved CDK4/6 inhibitor Abemaciclib can effectively restore cilia function in JBTS cells with defective glutamylation. In summary, our study elucidates the regulatory mechanisms governing axoneme polyglutamylation and suggests that developing CDK6-specific inhibitors could be a promising therapeutic strategy to enhance cilia function in ciliopathy patients.

Neuropathic pain is a debilitating chronic condition that lacks effective treatment. The role of cytokine- and chemokine-mediated neuroinflammation in its pathogenesis has been well documented. Follistatin (FST) is a secreted protein known to antagonize the biological activity of cytokines in the transforming growth factor–β (TGF-β) superfamily. The involvement of FST in neuropathic pain and the underlying mechanism remain largely unknown. Here, we report that FST was up-regulated in A-fiber sensory neurons after spinal nerve ligation (SNL) in mice. Inhibition or deletion of FST alleviated neuropathic pain and reduced the nociceptive neuron hyperexcitability induced by SNL. Conversely, intrathecal or intraplantar injection of recombinant FST, or overexpression of FST in the dorsal root ganglion (DRG) neurons, induced pain hypersensitivity. Furthermore, exogenous FST increased neuronal excitability in nociceptive neurons. The biolayer interferometry (BLI) assay and coimmunoprecipitation (co-IP) demonstrated direct binding of FST to the insulin-like growth factor–1 receptor (IGF1R), and IGF1R inhibition reduced FST-induced activation of extracellular signal–regulated kinase (ERK) and protein kinase B (AKT), as well as neuronal hyperexcitability. Further co-IP analysis revealed that the N-terminal domain of FST exhibits the highest affinity for IGF1R, and blocking this interaction with a peptide derived from FST attenuated Nav1.7-mediated neuronal hyperexcitability and neuropathic pain after SNL. In addition, FST enhanced neuronal excitability in human DRG neurons through IGF1R. Collectively, our findings suggest that FST, released from A-fiber neurons, enhances Nav1.7-mediated hyperexcitability of nociceptive neurons by binding to IGF1R, making it a potential target for neuropathic pain treatment.

Introduction: Neonatal pig hearts exhibit remarkable regenerative capacity within two days post-birth. In this study, we propose that a comprehensive multiomics analysis encompassing circRNA, miRNA, and mRNA data from neonatal mouse hearts can unveil intricate circRNA-miRNA-mRNA relationships associated with cardiac regeneration. Our aim is to identify new novel circRNAs and miRNAs implicated in cardiomyocyte proliferation through leveraging multiomics analysis. Methods: Utilizing neonatal mouse hearts, we conducted circRNA, miRNA, and mRNA sequencing across four different postnatal days (P1, P3, P7, and P28; n=6, encompassing both males and females). We employed integrative bioinformatics analyses across distinct experimental designs (P1 vs P3, P1 vs P7, and P1 vs P28). Back splice junctions generated by CIRCexplorer2’s parse command was utilized to annotate sequenced circRNAs as known or novel. Validation of circRNA, miRNA, and mRNA expression levels was achieved through qRT-PCR, while protein expression levels were assessed via western blotting. Fluorescence in situ hybridization (FISH) technology was employed to determine circRNA localization. The functional significance of key genes involved in cardiomyocyte proliferation was assessed via siRNA-mediated knockdown of circRNAs and miRNAs, accompanied by cell cycle assessment using bioluminescence assay and immunostaining. Results: Intersection of differentially expressed target genes from circRNA, miRNA, and mRNA analyses at each experimental design facilitated the construction of circRNA-miRNA-mRNA regulatory networks, aiding in the development of cardiac regeneration-related regulatory networks and inference of novel relationships between circRNA, miRNA, and mRNA. Integrative bioinformatics analysis revealed significant alterations in circRNA-miRNA-mRNA expression profiles during postnatal cardiomyocyte maturation in mice. Pathway enrichment analysis identified several differentially expressed circRNAs enriched in cell division and proliferation-related pathways. qPCR and cell cycle studies identified 17 potential circRNAs associated with cardiomyocyte proliferation in mice, with knockdown of these circRNAs significantly impacting cardiomyocyte cell cycle. Conclusion: Our findings suggest a crucial role for circRNAs in the regulation of neonatal myocardial regeneration.

ABSTRACT Background The optimal exercise regimen for alleviating sarcopenia remains uncertain. This study aimed to investigate the efficacy of high‐intensity interval training (HIIT) over moderate‐intensity continuous training (MICT) in ameliorating sarcopenia. Methods We conducted a randomized crossover trial to evaluate plasma proteomic reactions to acute HIIT (four 4‐min high‐intensity intervals at 70% maximal capacity alternating with 4 min at 30%) versus MICT (constant 50% maximal capacity) in inactive adults. We explored the relationship between a HIIT‐specific protein relative to MICT, identified via comparative proteomic analysis, eukaryotic translation elongation factor 1 epsilon 1 (EEF1E1) and sarcopenia in a paired case–control study of elderly individuals (aged over 65). Young (3 months old) and aged (20 months old) mice were randomized to sedentary, HIIT and MICT groups (five sessions/week for 4 weeks; n = 8 for each group). Measurements included skeletal muscle index, hand grip strength, expression of atrophic markers Atrogin1 and MuRF1 and differentiation markers MyoD, myogenin and MyHC‐II via western blotting. We examined the impact of EEF1E1 siRNA and recombinant protein on D‐galactose‐induced myoblast senescence, measuring senescence‐associated β‐galactosidase and markers like p21 and p53. Results The crossover trial, including 10 sedentary adults (32 years old, IQR 31–32) demonstrated significant alterations in the abundance of 21 plasma proteins after HIIT compared with MICT. In the paired case–control study of 84 older adults (84 years old, IQR 69–81; 52% female), EEF1E1 was significantly increased in those with sarcopenia compared to those without (14.68 [95%CI, 2.02–27.34] pg/mL, p = 0.03) and was associated with skeletal muscle index ( R 2 = 0.51, p < 0.001) and hand grip strength ( R 2 = 0.54, p < 0.001). In the preclinical study, aged mice exhibited higher EEF1E1 mRNA and protein levels in skeletal muscle compared to young mice, accompanied by a lower muscle mass and strength, increased cellular senescence and protein degradation markers and reduced muscle differentiation efficiency (all p < 0.05). HIIT reduced EEF1E1 expression and mitigated age‐related muscle decline and atrophy in aged mice more effectively than MICT. Notably, EEF1E1 downregulation via siRNA significantly counteracted D‐galactose‐induced myoblast senescence as evidenced by reduced markers of muscle protein degradation and improved muscle differentiation efficiency (all p < 0.05). Conversely, treatments that increased EEF1E1 levels accelerated the senescence process ( p < 0.05). Further exploration indicated that the decrease in EEF1E1 was associated with increased SIRT1 level and enhanced autophagy. Conclusions This study highlights the potential of HIIT as a promising approach to prevent and treat sarcopenia while also highlighting EEF1E1 as a potential intervention target.