Citations

BACKGROUND: TRPC6 (transient receptor potential canonical 6) channels, encoded by the TRPC6 gene, are widely expressed in cardiomyocytes and play a critical role in maintaining intracellular Ca 2 + homeostasis. Variants in TRPC6 are associated with chemotherapy-related cardiomyopathy. Specifically, the TRPC6 A404V polymorphism, with a minor (404 V) allele frequency of 12% in the general population, has been identified in patients undergoing anthracycline therapy. However, the underlying mechanisms remain largely unexplored. METHODS: Using patch-clamp recordings, Ca 2 + imaging, computational analysis, and molecular biology techniques, we assessed the effects of doxorubicin and its metabolite, doxorubicinol, on regulating TRPC6 alanine (A) at position 404 replaced by valine (V; A404V) channel expression and function in a heterologous expression system and native cardiac cells. RESULTS: Both additive and recessive models demonstrated a significant association between the TRPC6 A404V variant and doxorubicin-related cardiomyopathy. The TRPC6 A404V channel exhibited higher membrane expression levels compared with the wild type (WT) control. Patch-clamp recordings showed that both TRPC6 WT and A404V channels remained mostly inactive at baseline. Application of 50 μmol/L 1-oleoyl acetyl-sn-glycerol (OAG), a TRPC6 activator, significantly increased the inward- and outward-current densities of WT and A404V channels. Furthermore, a 24-hour treatment with 0.5 μmol/L doxorubicin enhanced TRPC6 mRNA expression and potentiated the OAG effects on both WT and A404V channels, with a more pronounced response in A404V channels. Treatment with 0.5 μmol/L doxorubicinol had no effect on OAG-induced current densities in either WT or A404V channels. Doxorubicin effects on intracellular Ca 2 + levels were confirmed by Ca 2 + imaging in native cardiac cells. Computational modeling revealed that the A404V mutation induces a conformational change in the OAG-binding pocket, enhancing its interaction with OAG in the A404V protein compared with the WT control. CONCLUSIONS: The TRPC6 A404V is a gain-of-function variant that exhibits enhanced activity in the presence of doxorubicin. Therefore, the TRPC6 A404V variant represents a risk factor for anthracycline-induced cardiotoxicity in patients with cancer.

Background While delivery of supplemental oxygen is a life-saving therapy, exposure to high oxygen, called hyperoxia, leads to increased intensive care unit mortality. Hyperoxia induces oxidant-mediated acute lung injury (ALI) and pulmonary cell death, called hyperoxic ALI (HALI). Elucidating molecular mechanisms in HALI could identify therapeutic targets in ALI. Methods In the current study, we examined in vivo effects of HALI on Beclin-1 (BCN1), which regulates autophagy, and modulation of BCN1 by epidermal growth factor receptor (EGFR). Effects of HALI on BCN1 and autophagy were examined in mice with genetically decreased EGFR (EGFR Wa5/+ ). Wildtype (WT) and EGFR Wa5/+ mice were exposed to 100% oxygen for 24–72 hours along with normoxia controls (eight groups; n=4–6/group), and analysis of pulmonary BCN1 and autophagy was completed. Results In WT, HALI led to increased BCN1 (59% increased total BCN1/β-Actin; p<0.01) in lung and alveolar epithelium (484% increased H-score; p<0.001). HALI led to decreased microtubule-associated protein 1B-light chain (LC3B)-II/-I ratios (43% decrease; p<0.05) and increased p62 (93% increase; p<0.05), suggesting reduced autophagic flux. In human alveolar type-II cells derived from induced pluripotent stem cells (AT2s iPSC ), HALI caused increased LDH release (130% increase; p<0.0001) and decreased LC3B-II/-I ratios (32% decrease; p<0.05). We previously showed that EGFR Wa5/+ mice are protected in HALI. In the current study, EGFR Wa5/+ mice showed increased pulmonary BCN1 (122% increase; p<0.05), reduced phosphorylated-(p-)/total BCN1 (47% decrease; p<0.05) and decreased LC3B-II/-I ratios (70% decrease; p<0.01) in HALI compared with WT. In addition, wortmannin (1 mg/kg), which decreases BCN1-mediated autophagy, increased mortality in HALI compared with vehicle control (n=10/group; 18% decreased hours survived; p<0.001). Conclusions These data delineate a novel cell death pathway in HALI involving BCN1 and EGFR with therapeutic potential.

INTRODUCTION: This study used the novel C-reactive protein-albumin-lymphocyte (CALLY) index to explore its relationship with the risk of developing gallstones. METHODS: This study conducted a cross-sectional analysis of the National Health and Nutrition Examination Survey data from 2017 to 2020; multivariable logistic regression examined the CALLY-gallstone association. Restricted cubic splines tested nonlinearity. Subgroup and mediation analyses explored population variations and mediating effects (Conicity, lipid accumulation product, and a body shape index). Receiver operating characteristic curves compared CALLY, systemic immune inflammation index, systemic inflammatory response index, and aggregate index of systemic inflammation predictive performance. RESULTS: After comprehensive adjustments, the highest CALLY quartile had significantly lower gallstone risk vs the lowest (odds ratio 0.56, 95% confidence interval 0.34–0.94). Restricted cubic splines revealed a linear inverse correlation. Subgroup analyses generally supported this inverse relationship. Mediation analysis identified the Conicity index as the strongest mediator (21.47%, P < 0.001), followed by lipid accumulation product and a body shape index (10.72% each, P < 0.001). Receiver operating characteristic analysis showed CALLY (area under the curve = 0.604) outperformed systemic immune inflammation index (0.540), systemic inflammatory response index (0.550), and aggregate index of systemic inflammation (0.546). DISCUSSION: A significant inverse association exists between the CALLY index and gallstone prevalence. The CALLY index demonstrates superior predictive ability compared with other indices, suggesting its potential utility as an objective biomarker for early gallstone risk identification.

Abstract Introduction The Hunger Vital Sign (HVS) is a two‐item, validated food insecurity screener recommended by the American Academy of Pediatrics. Given its brevity, HVS could be useful in assessing food insecurity in pregnant populations, for whom high‐quality nutrition and food access is essential. However, the HVS has not been evaluated in obstetric settings. Thus, we aimed to evaluate the performance of the HVS compared to the gold standard, the 18‐item US Household Food Security Survey Module (HFSSM) among low‐income, urban pregnant people. Methods We conducted a prospective study at a multi‐hospital tertiary health system (September 2023 to April 2024) in the United States. English‐ or Spanish‐speaking individuals from zip codes in which ≥10% of households were under the federal poverty line or who had publicly funded antenatal care completed a 20‐min self‐administered survey, which included the HFSSM and HVS. Food insecurity was defined as marginal, low, or very low food insecurity on the HFSSM; the prevalence of food insecurity was assessed and evaluated by participant characteristics. A positive screen on the HVS was defined as a “often true” or “sometimes true” to either item. Descriptive statistics were performed to characterize the performance of the HVS compared to the HFSSM. Results Of 713 potentially eligible participants based on medical record review, 192 (27%) completed an eligibility screener and were found to be eligible. Of these, 171 (89%) completed the survey. Nearly half (41%) of participants ( n = 70; of whom 74% received publicly funded care) screened positive for food insecurity on the HFSSM. HVS sensitivity was 83%, while specificity was 96%. The positive predictive value of the HVS was 94% and negative predictive value was 89%. Conclusion The two‐item HVS had relatively high accuracy for detecting food insecurity in this low‐income, urban obstetric population. Incorporating this brief screener into prenatal care may enable efficient, clinically useful food insecurity detection and intervention to address this need.

Abstract SRD5A3-CDG is a rare autosomal recessive congenital disorder of glycosylation characterized by multisystemic dysfunction, including neurological, psychomotor, cognitive, and visual impairments. Approximately 60 cases have been reported, with treatment limited to symptomatic management. SRD5A3 encodes a polyprenal reductase enzyme essential for synthesizing dolichol, a lipid carrier of the oligosaccharide precursor in N-glycosylation. To address the lack of effective treatments and disease models suitable for high-throughput screening, we developed the first C. elegans model of SRD5A3-CDG, harboring the homozygous W19X nonsense mutation commonly observed in patients. This model recapitulates disease-relevant phenotypes, including developmental delays, neurological dysfunction, and mevalonate pathway dysregulation. Using this model, we conducted a high-throughput motility-based drug repurposing screen and identified atorvastatin, an FDA-approved HMG-CoA reductase inhibitor, as a repurposing candidate. Atorvastatin rescued disease-relevant phenotypes in the worm model and restored polyprenol-to-dolichol ratios in patient fibroblasts. These findings highlight atorvastatin as a promising drug repurposing candidate for SRD5A3-CDG.

Abstract Background Invasive aspergillosis (IA) remains a common cause of both direct and contributable mortality in patients with hematologic malignancies (HM). Given the advances in antifungal management, it would be important to assess IA-attributable mortality (AM) and contributable mortality (CM), in addition to overall mortality (OM). Methods We retrospectively reviewed the records of 76 consecutive HM patients with proven/probable culture-positive IA (MSG/EORTC criteria) from 2015 to 2021. Death causality was adjudicated based on published criteria. AM was defined as death “due to” IA, while CM as death “due to” and “with” IA. OM encompassed death from any cause. Mortality rates and death causalities were evaluated at 2-, 4-, 6-, and 12-week intervals following IA diagnosis. A multivariate competing risk analysis was performed to identify independent risk factors for 6-week AM, with other death causalities as the competing event. To increase diagnostic accuracy, we excluded culture-negative, Aspergillus galactomannan (GM) positive cases, as GM can be produced by other hyalohyphomycetes. Results The median patient age was 60 years (61%). Lymphoma and multiple myeloma (L/MM) were the most common HM (40, 53%). The remaining patients had active leukemia. Twenty-nine patients (38%) had prior stem cell transplantation, and 10 (13%) had graft-versus-host disease. Aspergillus fumigatus was the most common species (47%). Six and 12-week mortality rates were 18.7% and 22.7% for AM, 42.7% and 49.3% for CM, and 45.3% and 53.3% for OM, respectively. Notably, 2-week OM was 27.6%. Lack of neutrophil recovery was the only independent risk factor for 6-week AM on multivariate analysis (OR=4.2, p=0.006). Conclusion Our findings reflect the modern reality of culture-documented IA, occurring mostly in HM patients with heavily pretreated L/MM not routinely receiving mold-active prophylaxis, and in those with active leukemia. In this real-life contemporary HM population, culture-positive IA was associated with high cumulative OM and CM. Understanding AM and CM rates could lead to more accurate sample size estimations in clinical mycology trials. Such trials should be pragmatic and assess antifungal failure at an earlier time point than the traditional 4-week mark post-diagnosis. Disclosures Dimitrios P. Kontoyiannis, MD, AbbVie, Inc: Advisory Board Participation|Astellas: Grant/Research Support|Basilea: Advisor/Consultant|Cidara, Inc: Advisory Board Participation|F2G, Inc: Advisor/Consultant|Gilead: Advisor/Consultant|Gilead: Grant/Research Support|Knight, Inc: Honoraria|Pfizer: Advisor/Consultant|Scynexis: Advisor/Consultant|TTF Pharmaceuticals, Inc: Advisor/Consultant|US-Israel Binational Sci Foundation: Grant/Research Support

Significance: Immune checkpoint inhibitors (ICIs) have transformed cancer therapy by reactivating antitumor immunity and improving outcomes across multiple malignancies. Yet, clinical observations and preclinical studies suggest that ICIs may increase long-term cardiovascular disease risk, including hypertension, atherosclerosis, and thrombosis. The underlying mechanisms remain incompletely defined, highlighting the need for focused investigation into the vascular consequences of immune activation. Recent Advances: ICI-induced immune activation disrupts vascular and immune homeostasis through persistent production of reactive oxygen species (ROS), mitochondrial dysfunction, and accumulation of cell-free DNA (cfDNA). Sustained T-cell activation enhances ROS generation, driving DNA damage and senescence in both endothelial and immune cells. ICIs may also promote endothelial-to-mesenchymal transition (EndoMT) through chronic oxidative and inflammatory signaling, contributing to fibrosis, vascular stiffness, and chronic inflammation. Transforming growth factor-beta, although immunosuppressive in many contexts, can drive profibrotic and EndoMT programs within the vasculature. Other cytokines and regulators, including interleukin-17 and regulator of calcineurin 1, have been implicated in vascular remodeling, atherosclerosis, and hypertension. Critical Issues: The relative roles of ROS, mitochondrial dysfunction, cfDNA-driven inflammation, and EndoMT in ICI-associated vascular senescence remain unclear. While inflammation-induced vascular damage is well-recognized, direct ICI-specific mechanisms require stronger evidence. How senescent endothelial and immune cells influence therapy resistance and remodeling of the tumor microenvironment also remains to be defined. Future Directions: Mitochondrial and cytosolic ROS sources—arising from electron leakage during oxidative phosphorylation and NADPH oxidases activity—shape immune signaling and sustain T-cell activation during checkpoint blockade. The DNA damage response kinases ataxia-telangiectasia mutated and ATM- and Rad3-related, activated by oxidative and replicative stress, engage p53-dependent senescence pathways in endothelial and immune cells. Future studies should evaluate biomarkers such as cfDNA and thrombospondin-1 and explore senescence-targeting or redox-modulating interventions that may alleviate cardiovascular toxicity without diminishing antitumor efficacy. This review outlines mechanistic pathways linking ICIs to vascular dysfunction and senescence, integrating preclinical data with emerging clinical insights. It distinguishes established processes from ICI-specific hypotheses and identifies key gaps requiring clinical validation. Antioxid. Redox Signal. 00, 000–000.

Abstract INTRODUCTION Tau species lacking truncation of the N‐terminal region, including plasma N‐terminal tau fragment 1 (NT1), have been previously associated with cognitive decline, neurodegeneration, and tau pathology in late‐onset sporadic Alzheimer's disease (AD). METHODS Here, we examined cross‐sectional and longitudinal plasma NT1 as a possible predictor of cognitive, clinical, and core AD biomarker trajectories in autosomal dominant AD (ADAD). RESULTS NT1 levels in ADAD mutation carriers (MC; n = 132) increased across the disease continuum, compared to non‐carriers (NC; n = 75), becoming elevated about a decade prior to estimated symptom onset. Cross‐sectional and longitudinal NT1 levels in MC were associated with clinical, cognitive, and biomarker changes. NT1 increases continued in symptomatic phases of disease, a distinct trajectory from that seen with CSF p‐tau217 and other phospho‐tau species. DISCUSSION Together, our results suggest that plasma NT1—alone or combined with other tau measures—may be useful in studying AD‐related clinical, cognitive, and biomarker outcomes. Highlights Leveraging a deeply phenotyped cohort of individuals carrying a pathogenic variant for autosomal dominant Alzheimer's disease (ADAD) and their non‐carrier family members, our results suggest that plasma N‐terminal tau fragment 1 (NT1) levels mirrored changes in clinical, cognitive, and neurodegenerative measures in ADAD, particularly in late asymptomatic and early symptomatic phases of disease. NT1 levels correlated with cerebrospinal fluid (CSF) measures of tau pathology but less so with CSF or imaging measures of β‐amyloid pathology. Together with previous supportive findings in preclinical and symptomatic sporadic AD, these results suggest that plasma NT1—alone or combined with other tau measures—may be useful in studying AD‐related tau pathology and neurodegeneration across a wide spectrum of disease.

ABSTRACT Gain-of-function mutations in the transient receptor potential 6 (TRPC6) channel have recently been recognized as risk factors for both doxorubicin (DOX)-induced cardiomyopathy. Functional evaluation of TRPC6 missense variants is therefore important for cancer patients undergoing anthracycline treatment. However, traditional electrophysiological methods are labor-intensive and time-consuming. In this study, we compared the functional responses of TRPC6 missense variants to 1-oleoyl-2-acetyl-sn-glycerol (OAG), a TRPC6 agonist, using molecular docking and patch clamp recording techniques. For the wild-type (WT) TRPC6 structure (PDB ID: 6UZ8), OAG exhibited a binding energy of -4.49 kcal/mol and a dissociation constant (Kd) of 0.511 mM. Twenty TRPC6 missense variants were identified from cancer patients in the Mayo Clinic database. Of these, fifteen variants had resolvable structures, nine of which displayed increased Kd values and six decreased Kd values compared to WT in molecular docking analysis. Patch clamp recordings revealed that TRPC6 WT and mutant channels were inactive at baseline but were activated upon 50 μM OAG stimulation, except two loss-of-function variants. Moreover, a 24-h treatment with 0.5 μM DOX significantly enhanced OAG-induced channel activation. All three variants identified in patients with heart failure demonstrated gain-of-function properties in both electrophysiological measurements and in-silico predictions. Importantly, the results obtained from molecular docking and patch clamp recordings were strongly correlated, showing an 82% concordance, higher than the predictions from AlphaMissense. These findings indicate that our computational analysis provides a rapid and reliable method for predicting the functional impact of TRPC6 missense variants, which may aid clinical decision-making in cancer patients receiving chemotherapy.

Acute myocardial infarction (AMI) is a significant factor leading to the death of patients with coronary heart disease. Both AMI and reperfusion therapy after AMI cause myocardial cell death, which plays a significant role in heart failure. Following the restoration of blood flow during reperfusion, myocardial cells generate a large amount of oxygen free radicals, causing various forms of myocardial ischemia–reperfusion (IR) injury (IRI), ultimately leading to multiple types of myocardial cell death, among which apoptosis and necroptosis are the two major types. Given the extremely limited regenerative capacity of myocardium, inhibiting myocardial cell apoptosis and necroptosis is a key strategy for reducing mortality in patients with AMI. Both apoptosis and necroptosis are regulated by the BCL2 family of proteins, which were modulated by multiple signaling pathways, converging at BAK/BAX-mediated mitochondrial outer membrane permeabilization (MOMP), as well as mitochondrial inner membrane permeabilization (MIMP). BAK/BAX double knock out (DKO) mice showed reduced cell apoptosis, necroptosis, and infarct size in AMI animal models compared to wild type. This review describes the role of BCL2 family proteins in regulating apoptotic and necroptotic myocardial cell death during AMI and IR, explores the upstream pathways modulating apoptosis and necroptosis, and summarizes the recent advances in targeting BAK and/or BAX for cardiac protection. In addition, targeted delivery of BAK/BAX inhibitors to cardiomyocytes during AMI or myocardial IR has the potential to reduce myocardial cell death and therefore lower the mortality and enhance long-term prognosis for myocardial infarction patients.