Search

ObjectivesDetermine the role of apolipoprotein M (ApoM) in anthracycline (Dox) cardiotoxicity.BackgroundApoM binds the cardioprotective sphingolipid sphingosine-1-phosphate (S1P). Circulating ApoM is inversely associated with mortality in human heart failure (HF).MethodsIn the Penn HF Study (PHFS), we tested the relationship between ApoM and mortality in a subset with anthracycline-induced cardiomyopathy. We measured ApoM in humans and mice treated with Dox and utilized hepatic ApoM transgenic (ApomTG), ApoM knockout (ApomKO), ApoM knock-in mice with impaired S1P binding, and S1P receptor 3 (S1PR3) knockout mice in Dox cardiotoxicity. We assayed autophagy in left ventricular tissue from anthracycline-induced HF patients versus donor controls.ResultsApoM was inversely associated with mortality in PHFS, and Dox reduced circulating ApoM in mice and breast cancer patients.ApomTGmice were protected from Dox-induced cardiac dysfunction and loss of left ventricular mass.ApomTGattenuated Dox-induced impairment in autophagic flux in vivo and accumulation of insoluble p62, which was also observed in the myocardium of patients with anthracycline-induced HF. In vehicle-treated mice, ApoM negatively regulated transcription factor EB (TFEB), a master regulator of autophagy and lysosomal biogenesis. The effect of ApoM on TFEB required both S1P binding and S1PR3. In the presence of Dox, ApoM preserved TFEB and cardiomyocyte lysosomal abundance assessed as lysosomal associated membrane protein 1 positive structures in vivo, while S1P mimetic pretreatment of cardiomyocytes prevented Dox-induced changes in lysosomal pH.ConclusionsApoM attenuates Dox cardiotoxicity via the autophagy-lysosome pathway. The association between ApoM and reduced mortality may be explained by its role in sustaining autophagy.HighlightsCirculating ApoM is inversely associated with survival in human anthracycline-induced cardiomyopathyAnthracycline treatment reduces circulating ApoM in humans and miceIncreasing ApoM attenuates doxorubicin cardiotoxicity, lysosomal injury and preserves myocardial autophagic flux, but does not impact doxorubicin anti-neoplastic efficacyAutophagic impairment is characteristic of human anthracycline cardiomyopathy

Summary Background COVID-19 can lead to multiorgan failure. Dapagliflozin, a SGLT2 inhibitor, has significant protective benefits for the heart and kidney. We aimed to see whether this agent might provide organ protection in patients with COVID-19 by affecting processes dysregulated during acute illness. Methods DARE-19 was a randomised, double-blind, placebo-controlled trial of patients hospitalised with COVID-19 and with at least one cardiometabolic risk factor (ie, hypertension, type 2 diabetes, atherosclerotic cardiovascular disease, heart failure, and chronic kidney disease). Patients critically ill at screening were excluded. Patients were randomly assigned 1:1 to dapagliflozin (10 mg daily orally) or matched placebo for 30 days. Dual primary outcomes were assessed in the intention-to-treat population: the outcome of prevention (time to new or worsened organ dysfunction or death), and the hierarchial composite outcome of recovery (change in clinical status by day 30). Safety outcomes, in patients who received at least one study medication dose, included serious adverse events, adverse events leading to discontinuation, and adverse events of interest. This study is registered with ClinicalTrials.gov , NCT04350593 . Findings Between April 22, 2020 and Jan 1, 2021, 1250 patients were randomly assigned with 625 in each group. The primary composite outcome of prevention showed organ dysfunction or death occurred in 70 patients (11·2%) in the dapagliflozin group, and 86 (13·8%) in the placebo group (hazard ratio [HR] 0·80, 95% CI 0·58–1·10; p=0·17). For the primary outcome of recovery, 547 patients (87·5%) in the dapagliflozin group and 532 (85·1%) in the placebo group showed clinical status improvement, although this was not statistically significant (win ratio 1·09, 95% CI 0·97–1·22; p=0·14). There were 41 deaths (6·6%) in the dapagliflozin group, and 54 (8·6%) in the placebo group (HR 0·77, 95% CI 0·52–1·16). Serious adverse events were reported in 65 (10·6%) of 613 patients treated with dapagliflozin and in 82 (13·3%) of 616 patients given the placebo. Interpretation In patients with cardiometabolic risk factors who were hospitalised with COVID-19, treatment with dapagliflozin did not result in a statistically significant risk reduction in organ dysfunction or death, or improvement in clinical recovery, but was well tolerated. Funding AstraZeneca.

Ceramides are a class of bioactive sphingolipids increasingly recognized in metabolic disease, heart failure (HF), atherosclerosis, and cardiovascular death ([1][1]). Despite accumulating evidence linking ceramides to HF risk, little is known about circulating ceramides and clinical outcomes in HF

Previous studies demonstrate that the Montney rock samples have a dual-wettability pore network. Recovery of the oil retained in small hydrophobic pores is a unique challenge. In this study, we apply dual-core imbibition (DCI) method on several Montney core plugs and introduce imbibition-recovery (IR) trio to investigate the recovery mechanisms in rocks with dual-wettability pore network. First, we evaluate the wetting affinity of five twin core-plugs from the Montney Formation by measuring spontaneous imbibition of reservoir oil and brine, and by measuring equilibrium contact angle. We place one plug of each pair in the oil and the other in the brine, and measure the weight change periodically. Second, we place the oil-saturated plugs in the brine to visualize the expelled oil droplets and measure volume of the recovered oil. We comparatively analyze the spontaneous imbibition data from the first step and the oil recovery data from the second step in one imbibition-recovery trio (oil imbibition, brine imbibition, and imbibition oil recovery). The results of air-liquid contact angle and spontaneous imbibition tests on dry samples suggest that affinity of the samples to oil is higher than that to brine, in an air-liquid system. However, the results of liquid-liquid contact angle and counter-current imbibition tests suggest that affinity of the samples to water is higher than that to oil, in a liquid-liquid system. For each twin set, the oil recovery curve follows the trend of brine imbibition curve, and the final oil recovery is always less than the equilibrated water uptake of dry samples. This observation indicates that water can only access the hydrophilic part of the pore network initially saturated with oil.

Endothelial function may be deranged in heart failure with preserved ejection fraction (HFpEF). Serum NO-derived metabolites (NO m ) might provide a biochemical surrogate of endothelial function in patients with heart failure (HF). We measured serum NO m in 415 participants in the Penn HF Study. Participants with HFpEF (n = 82) and those whose EF had recovered (Recovered-HF, n = 125) were matched 1:1 to heart failure with reduced ejection fraction (HFrEF) participants based on age, gender, race, tobacco use, and eGFR. Serum NO m levels were quantified after chemical reduction coupled with gas-phase chemiluminescence detection. After adjustment for matching covariates and BMI, HFpEF (34.5 μM; interquartile range [IQR] 25.0, 51.5) participants had lower NO m levels than HFrEF (41.0 μM; IQR 28.3, 58.0; ratio of HFpEF:HFrEF 0.82, 95% confidence interval [CI] 0.67 to 0.99; p = 0.04), which further decreased when adjusted for covariates that affect endothelial function (ratio 0.79, 95% CI 0.65 to 0.98; p = 0.03). There were no differences between HFrEF (34.0; IQR 25.3, 49.0) and matched Recovered-HF (36.0 μM; IQR 25.0, 55.0) or HFpEF and Recovered-HF. Age (+21%/10-year increase, p m in HFpEF, whereas age (+11%/10-year increase, p = 0.03), current tobacco use (+67%, p = 0.01), and eGFR (p = 0.01) associated with NO m in Recovered-HF. In conclusion, HFpEF participants have reduced NO m compared with HFrEF in this matched cohort. This might suggest either compromised endothelial function or poor dietary intake. Black race was associated with lower NO m in HFpEF.

Background Cardiac allograft vasculopathy (CAV) is a major cause of mortality after cardiac transplantation. High-density lipoprotein (HDL) cholesterol efflux capacity (CEC) is inversely associated with coronary artery disease. In 2 independent studies, we tested the hypothesis that reduced CEC is associated with mortality and disease progression in CAV. Methods We tested the relationship between CEC and survival in a cohort of patients with CAV ( n = 35). To determine whether reduced CEC is associated with CAV progression, we utilized samples from the Clinical Trials in Organ Transplantation 05 (CTOT05) study to determine the association between CEC and CAV progression and status at 1 year ( n = 81), as assessed by average change in maximal intimal thickness (MIT) on intravascular ultrasound. Results Multivariable Cox proportional hazard models demonstrated that higher levels of CEC were associated with improved survival (hazard ratio 0.26, 95% confidence interval 0.11 to 0.63) per standard deviation CEC, p = 0.002). Patients who developed CAV had reduced CEC at baseline and 1-year post-transplant. We observed a significant association between pre-transplant CEC and the average change in MIT, particularly among patients who developed CAV at 1 year (β = −0.59, p = 0.02, R 2 = 0.35). Conclusion Reduced CEC is associated with disease progression and mortality in CAV patients. These findings suggest the hypothesis that interventions to increase CEC may be useful in cardiac transplant patients for prevention or treatment of CAV.

Background & Aims The lysosome is an acidic organelle that is important for maintaining cellular and metabolic homeostasis in hepatocytes. Lysosomal dysfunction and chronic inflammation coexist, and both contribute to obesity-associated hepatic insulin resistance. However, in the context of obesity, the interplay between inflammatory signals and hepatic lysosomal function remains largely unknown. Inducible nitric oxide synthase (iNOS) is a hallmark for inflammation, and is activated in obesity. The aim of this study is to understand the molecular link between iNOS-mediated lysosomal nitric oxide (NO) production, hepatic lysosomal function, and autophagy in the context of obesity-associated insulin resistance. Methods The role of iNOS in hepatic autophagy, as related to insulin and glucose homeostasis were studied in mice with diet-induced obesity (DIO). The effects and mechanisms of iNOS-mediated lysosomal NO production on lysosomal function and hepatic autophagy were studied in primary hepatocytes as well as in a mouse model of DIO. Results We demonstrate that obesity promotes iNOS localization to the lysosome and decreases levels of lysosomal arginine, resulting in an accumulation of NO in hepatic lysosomes. This lysosomal NO production is attenuated by treatment with a NO scavenger, while co-overexpression of mTOR and a lysosomal arginine transporter (SLC38A9) enhances lysosomal NO production and suppresses autophagy. In addition, we show that deletion of iNOS ameliorates lysosomal nitrosative stress in the livers of DIO mice, promotes lysosomal biogenesis by activating transcription factor EB (TFEB), and enhances lysosomal function and autophagy. Lastly, deletion of iNOS in mice with DIO improves hepatic insulin sensitivity, which is diminished by suppression of TFEB or autophagy related 7 (Atg7). Conclusions Our studies suggest that lysosomal iNOS-mediated NO signaling disrupts hepatic lysosomal function, contributing to obesity-associated defective hepatic autophagy and insulin resistance., Graphical abstract

Stable plasma nitric oxide metabolites (NOx), predominantly composed of nitrate, are markers of endogenous nitric oxide (NO) production, NO utilization, and dietary intake and may be indicators of vascular health. We enrolled subjects undergoing a clinically-indicated cardiac MRI. Plasma NOx levels

Obesity, Sleep Apnea, LV Remodeling and Myocardial Fibrosis Assessed with Cardiac MRI Both obesity and sleep apnea (SA) are predictive of heart failure (HF). Limited data are available regarding the independent effects of SA and obesity on left ventricular (LV) remodeling. We recruited 280