bims-hafaim 2024-08-11 papers

Issue of 2024–08–11
four papers selected by
Kyle McCommis, Saint Louis University

J Pharm Pharm Sci. 2024 ;27 13080

The role of acetylation in obesity-induced cardiac metabolic alterations.

Obesity is a growing public health problem, with its prevalence rate having tripled in the last five decades. It has been shown that obesity is associated with alterations in cardiac energy metabolism, which in turn plays a significant role in heart failure development. During obesity, the heart becomes highly dependent on fatty acid oxidation as its primary source of energy (ATP), while the contribution from glucose oxidation significantly decreases. This metabolic inflexibility is associated with reduced cardiac efficiency and contractile dysfunction. Although it is well recognized that alterations in cardiac energy metabolism during obesity are associated with the risk of heart failure development, the molecular mechanisms controlling these metabolic changes are not fully understood. Recently, posttranslational protein modifications of metabolic enzymes have been shown to play a crucial role in cardiac energy metabolic changes seen in obesity. Understanding these novel mechanisms is important in developing new therapeutic options to treat or prevent cardiac metabolic alteration and dysfunction in obese individuals. This review discusses posttranslational acetylation changes during obesity and their roles in mediating cardiac energy metabolic perturbations during obesity as well as its therapeutic potentials.

Keywords: cardiac energy metabolism; fatty acid oxidation; heart failure; obesity; protein lysine acetylation

DOI: https://doi.org/10.3389/jpps.2024.13080

Eur J Heart Fail. 2024 Aug 09.

Landscape of glycolytic metabolites and their regulating proteins in myocardium from human heart failure with preserved ejection fraction.

Navid Koleini, Mariam Meddeb, Liang Zhao, Mohammad Keykhaei, Seoyoung Kwon, Farnaz Farshidfar, Virginia S Hahn, Erika L Pearce, Kavita Sharma, David A Kass.

AIMS: Heart failure (HF) with preserved ejection fraction (HFpEF) reflects half of all clinical HF yet has few therapies. Obesity and diabetes are now common comorbidities which have focused attention towards underlying myocardial metabolic defects. The profile of a major metabolic pathway, glycolytic intermediates and their regulating enzymes and ancillary pathways, remains unknown.
METHODS AND RESULTS: Endomyocardial biopsies from HFpEF (n = 37) and non-failing controls (n = 21) were assayed by non-targeted or targeted metabolomics and immunoblot to determine glycolytic and ancillary pathway metabolites and protein expression of their regulating enzymes. Glucose and GLUT1 expression were higher in HFpEF, but prominent glycolytic metabolites: glucose-6-phosphate, fructose-1,6-biphosphate (F1,6bP), and 3-phosphoglycerate were reduced by -78%, -91%, and -73%, respectively, versus controls. Expression of their corresponding synthesizing enzymes hexokinase, phospho-fructokinase, and phosphoglycerate kinase were also significantly lower (all p < 0.0005). Pentose phosphate and hexosamine biosynthetic pathway metabolites were reduced while glycogen content increased. Despite proximal reduction in key glycolytic intermediates, pyruvate increased but mitochondrial pyruvate transporter (MPC1) expression was reduced. Pyruvate dehydrogenase converting pyruvate to acetyl-CoA was more activated but some Krebs cycle intermediates were reduced. This HFpEF glycolytic profile persisted after adjusting for body mass index (BMI), diabetes, age, and sex, or in subgroup analysis with controls and HFpEF matched for BMI and diabetes/insulin history. In HFpEF, BMI but not glycated haemoglobin negatively correlated with F1,6bP (p = 7e-5, r = -0.61) and phosphoenolpyruvate (p = 0.006, r = -0.46).
CONCLUSIONS: Human HFpEF myocardium exhibits reduced glycolytic and ancillary pathway intermediates and expression of their synthesizing proteins. This combines features reported in HF with reduced ejection fraction and obesity/diabetes that likely exacerbate metabolic inflexibility.

Keywords: Glycolysis; HFpEF; Heart failure; Human; Metabolomics; Myocardium

DOI: https://doi.org/10.1002/ejhf.3389

medRxiv. 2024 Jul 25. pii: 2024.07.24.24310961. [Epub ahead of print]

Targeted Quantitative Plasma Metabolomics Identifies Metabolite Signatures that Distinguish Heart Failure with Reduced and Preserved Ejection Fraction.

Fawaz Naeem, Teresa C Leone, Christopher Petucci, Clarissa Shoffler, Ravindra C Kodihalli, Tiffany Hidalgo, Cheryl Tow-Keogh, Jessica Mancuso, Iphigenia Tzameli, Donald Bennett, John D Groarke, Rachel J Roth Flach, Daniel J Rader, Daniel P Kelly.

Background: Two general phenotypes of heart failure (HF) are recognized: HF with reduced ejection fraction (HFrEF) and with preserved EF (HFpEF). To develop HF disease phenotype-specific approaches to define and guide treatment, distinguishing biomarkers are needed. The goal of this study was to utilize quantitative metabolomics on a large, diverse population to replicate and extend existing knowledge of the plasma metabolic signatures in human HF.
Methods: Quantitative, targeted LC/MS plasma metabolomics was conducted on 787 samples collected by the Penn Medicine BioBank from subjects with HFrEF (n=219), HFpEF (n=357), and matched non-failing Controls (n=211). A total of 90 metabolites were analyzed, comprising 28 amino acids, 8 organic acids, and 54 acylcarnitines. 733 of these samples were also processed via an OLINK protein panel for proteomic profiling.
Results: Consistent with previous studies, unsaturated forms of medium/long chain acylcarnitines were elevated in the HFrEF group to a greater extent than the HFpEF group compared to Controls. A number of amino acid derivatives, including 1- and 3-methylhistidine, homocitrulline, and symmetric (SDMA) and asymmetric (ADMA) dimethylarginine were elevated in HF, with ADMA elevated uniquely in HFpEF. Plasma branched-chain amino acids (BCAA) were not different across the groups; however, short-chain acylcarnitine species indicative of BCAA catabolism were significantly elevated in both HF groups. The ketone body 3-hydroxybutyrate (3-HBA) and its metabolite C4-OH carnitine were uniquely elevated in the HFrEF group. Linear regression models demonstrated a significant correlation between plasma 3-HBA and NT-proBNP in both forms of HF, stronger in HFrEF.
Conclusions: These results identify plasma signatures that are shared as well as potentially distinguish between HFrEF and HFpEF. Metabolite markers for ketogenic metabolic re-programming in extra-cardiac tissues were identified as unique signatures in the HFrEF group, possibly related to the lipolytic action of increased levels of BNP. Future studies will be necessary to further validate these metabolites as HF biosignatures that may guide phenotype-specific therapeutics and provide insight into the systemic metabolic responses to HFpEF and HFrEF.
Clinical Perspective: What Is New?: "Real world" targeted metabolomic profiling on wide range of metabolites in a diverse population of patients with HFrEF and HFpEF.Levels of 3-hydroxybutyrate and its metabolite C4OH-carnitine were uniquely increased in the HFrEF group and correlated with levels of plasma NT-proBNP in both the heart failure groups, indicating the possibility of a heart-adipose-liver axis.Asymmetric dimethylarginine, a known inhibitor of nitric oxide synthase, was uniquely upregulated in HFpEF suggesting that there may also be an underlying component of vascular dysregulation contributing to HFpEF pathophysiology.What Are the Clinical Implications?: The plasma metabolomic changes seen in the heart failure cohorts support the existing theory of metabolic reprogramming, providing further rationale for the pursuit of therapeutic targets for the treatment of heart failure.Quantitative metabolomic profiling shows promise for guiding therapeutic decisions in HFrEF and HFpEF.Modulation of natriuretic peptides may enhance the delivery of ketone and fatty acids to the "fuel starved" failing heart.

DOI: https://doi.org/10.1101/2024.07.24.24310961

Circulation. 2024 Aug 05.

Dapagliflozin Enhances Arterial and Venous Compliance During Exercise in Heart Failure With Preserved Ejection Fraction: Insights From the Cardiac and Metabolic Effects of Dapagliflozin in Heart Failure With Preserved Ejection Fraction Trial.

Atsushi Tada, Daniel Burkhoff, Jwan A Naser, Tomonari Harada, Bianca Pourmussa, Yogesh N V Reddy, Michael D Jensen, Rickey Carter, Ryan T Demmer, Jeffrey Testani, Julio A Chirinos, Barry A Borlaug.

BACKGROUND: Systemic arterial compliance and venous capacitance are typically impaired in patients with heart failure with preserved ejection fraction (HFpEF), contributing to hemodynamic congestion with stress. Sodium-glucose cotransporter-2 inhibitors reduce hemodynamic congestion and improve clinical outcomes in patients with HFpEF, but the mechanisms remain unclear. This study tested the hypothesis that Dapagliflozin would improve systemic arterial compliance and venous capacitance during exercise in patients with HFpEF.
METHODS: In this secondary analysis from the Cardiac and Metabolic Effects of Dapagliflozin in Heart Failure With Preserved Ejection Fraction Trial, 37 patients with HFpEF (mean age 68 ± 9 years, women 65%) underwent invasive hemodynamic exercise testing with simultaneous echocardiography at baseline and following treatment for 24 weeks with Dapagliflozin or placebo. Radial artery pressure (BP) was measured continuously using a fluid-filled catheter with transformation to aortic pressure, central hemodynamics were measured using high-fidelity micromanometers, and stressed blood volume was estimated from hemodynamic indices fit to a comprehensive cardiovascular model.
RESULTS: There was no statistically significant effect of Dapagliflozin on resting BP, but Dapagliflozin reduced systolic BP during peak exercise (estimated treatment difference [ETD], -18.8 mm Hg [95% CI, -33.9 to -3.7] P=0.016). Reduction in BP was related to improved exertional total arterial compliance (ETD, 0.06 mL/mm Hg/m2 [95% CI, 0.003-0.11] P=0.039) and aortic root characteristic impedance (ETD, -2.6 mm Hg/mL*sec [95% CI: -5.1 to -0.03] P=0.048), with no significant effect on systemic vascular resistance. Dapagliflozin reduced estimated stressed blood volume at rest and during peak exercise (ETD, -292 mm Hg [95% CI, -530 to -53] P=0.018), and improved venous capacitance evidenced by a decline in ratio of estimated stressed blood volume to total blood volume (ETD, -7.3% [95% CI, -13.3 to -1.3] P=0.020). Each of these effects of Dapagliflozin at peak exercise were also observed during matched 20W exercise intensity. Improvements in total arterial compliance and estimated stressed blood volume were correlated with decreases in body weight, and reduction in systolic BP with treatment was correlated with the change in estimated stressed blood volume during exercise (r=0.40, P=0.019). Decreases in BP were correlated with reduction in pulmonary capillary wedge pressure during exercise (r=0.56, P<0.001).
CONCLUSIONS: In patients with HFpEF, treatment with Dapagliflozin improved systemic arterial compliance and venous capacitance during exercise, while reducing aortic characteristic impedance, suggesting a reduction in arterial wall stiffness. These vascular effects may partially explain the clinical benefits with sodium-glucose cotransporter-2 inhibitors in HFpEF.
REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04730947.

Keywords: Dapagliflozin; HFpEF; arterial compliance; arterial stiffness; exercise; heart failure; hemodynamics; mechanism; vascular stiffness; venous function

DOI: https://doi.org/10.1161/CIRCULATIONAHA.124.068788