Depletion of cardiac cardiolipin synthase alters systolic and diastolic function

Edible plant oils with high n-3/n-6 polyunsaturated fatty acids ratio prolong the lifespan of Drosophila by modulating lipid metabolism

Edible plant oils with a high n-3/n-6 polyunsaturated fatty acids (PUFAs) ratio exhibit numerous health benefits, potentially due to their ability to modulate cellular lipidomes metabolism within the organism. To test this hypothesis, lifespan studies in Drosophila were conducted to assess the impact of 7 representative plant oils with different n-3/n-6 PUFA ratios on health outcomes. Subsequently, multi-dimensional MS-based shotgun lipidomics was utilized for class-targeted lipid analysis of cellular lipidomes in fly bodies. The plant oils with high n-3/n-6 PUFAs ratio significantly extended the lifespan of Drosophila, enhancing overall health. Lipidomics analysis revealed that these oils substantially increased the composition of 18:3 free FA, reduced compositions of phospholipid species containing 18:2 FA in flies, and enhanced mitochondrial functions by elevating T18:2 cardiolipin composition. The study provides insights into the mechanism(s) underlying the positive health effects of plant oils with high n-3/n-6 PUFAs ratio.

Glycerophospholipid and Sphingosine- 1-phosphate Metabolism in Cardiovascular Disease: Mechanisms and Therapeutic Potential

Cardiovascular disease remains a leading cause of mortality worldwide, driven by factors such as dysregulated lipid metabolism, oxidative stress, and inflammation. Recent studies highlight the critical roles of both glycerophospholipid and sphingosine- 1-phosphate metabolism in the pathogenesis of cardiovascular disorders. However, the contributions of glycerophospholipid-derived metabolites remain underappreciated. Glycerophospholipid metabolism generates bioactive molecules that contribute to endothelial dysfunction, lipid accumulation, and cardiac cell injury while also modulating inflammatory and oxidative stress responses. Meanwhile, sphingosine- 1-phosphate is a bioactive lipid mediator that regulates vascular integrity, inflammation, and cardiac remodeling through its G-protein-coupled receptors. The convergence of these pathways presents novel therapeutic opportunities, where dietary interventions such as omega- 3 polyunsaturated fatty acids and pharmacological targeting of sphingosine- 1-phosphate receptors could synergistically mitigate cardiovascular risk. This review underscores the need for further investigation into the interplay between glycerophospholipid metabolism and sphingosine- 1-phosphate signaling to advance targeted therapies for the prevention and management of cardiovascular disease.

An altered plasma lipidome-phenome network characterizes heart failure with preserved ejection fraction

AIMS

Heart failure with preserved ejection fraction (HFpEF) is a multifactorial, multisystemic syndrome that involves alterations in lipid metabolism. This study aimed to test whether distinct plasma lipid profiles or lipid entities or both are associated with clinical and functional echocardiographic parameters in HFpEF.

METHODS AND RESULTS

We examined the human plasma lipidome in HFpEF patients (n = 18) with left ventricular ejection fraction ≥50% and N-terminal pro-brain natriuretic peptide (NT-proBNP) >125 pg/mL and control subjects (n = 12) using mass spectrometry-based shotgun lipidomics. The cohort included 8 women and 22 men with average age of 67.8 ± 8.6 SD. The control and disease groups were not significantly different with respect to age, body mass index, systolic and diastolic blood pressure, and waist-to-hip ratio. The disease group experienced more fatigue (P < 0.001), had more often coronary artery disease (P = 0.04), and received more medications (beta-blockers, P < 0.001). The disease group had significantly different levels of HFpEF-relevant parameters, including NT-proBNP (P < 0.001), left ventricular mass index (P = 0.005), left atrial volume index (P = 0.001), and left ventricular filling index (P < 0.001), and lower left ventricular end-diastolic diameter (P = 0.014), with no difference in left ventricular ejection fraction. Significant differences in lipid profiles between HFpEF patients and controls could not be detected, including no significant differences in abundance of circulating lipids binned by carbon chain length or by double bonds, nor at the level of individual lipid species. However, there was a striking correlation between selected lipids with smoking status that was independent of disease status, as well as between specific lipids and hyperlipidaemia [with corresponding significance of either false discovery rate (FDR) <0.1 or FDR < 0.01]. In an exploratory network analysis of correlations, we observed significantly stronger correlations within the HFpEF group between individual lipids from the cholesterol ester and phosphatidylcholine (PC) classes and clinical/echocardiographic parameters such as left atrial volume index, left ventricular end-diastolic diameters, and heart rate (FDR < 0.1). In contrast, the control group showed significantly stronger negative correlations (FDR < 0.1) between individual species from the PC and sphingomyelin classes and left ventricular mass index or systolic blood pressure.

CONCLUSIONS

We did not find significant direct associations between plasma lipidomic parameters and HFpEF and therefore could not conclude that any specific lipids are biomarkers of HFpEF. The validation in larger cohort is needed to confidently conclude the absence of first-order associations.

SIRT3 regulates cardiolipin biosynthesis in pressure overload-induced cardiac remodeling by PPARγ-mediated mechanism

Cardiac remodeling is the primary pathological feature of chronic heart failure (HF). Exploring the characteristics of cardiac remodeling in the very early stages of HF and identifying targets for intervention are essential for discovering novel mechanisms and therapeutic strategies. Silent mating type information regulation 2 homolog 3 (SIRT3), as a major mitochondrial nicotinamide adenine dinucleotide (NAD)-dependent deacetylase, is required for mitochondrial metabolism. However, whether SIRT3 plays a role in cardiac remodeling by regulating the biosynthesis of mitochondrial cardiolipin (CL) is unknown. In this study, we induced pressure overload in wild-type (WT) and SIRT3 knockout (SIRT3-/-) mice via transverse aortic constriction (TAC). Compared with WT mouse hearts, the hearts of SIRT3-/- mice exhibited more-pronounced cardiac remodeling and fibrosis, greater reactive oxygen species (ROS) production, decreased mitochondrial-membrane potential (ΔΨm), and abnormal mitochondrial morphology after TAC. Furthermore, SIRT3 deletion aggravated TAC-induced decrease in total CL content, which might be associated with the downregulation of the CL synthesis related enzymes cardiolipin synthase 1 (CRLS1) and phospholipid-lysophospholipid transacylase (TAFAZZIN). In our in vitro experiments, SIRT3 overexpression prevented angiotensin II (AngII)- induced aberrant mitochondrial function, CL biosynthesis disorder, and peroxisome proliferator-activated receptor gamma (PPARγ) downregulation in cardiomyocytes; meanwhile, SIRT3 knockdown exacerbated these effects. Moreover, the addition of GW9662, a PPARγ antagonist, partially counteracted the beneficial effects of SIRT3 overexpression. In conclusion, SIRT3 regulated PPARγ-mediated CL biosynthesis, maintained the structure and function of mitochondria, and thereby protected the myocardium against cardiac remodeling.

Momordicine I alleviates isoproterenol-induced cardiomyocyte hypertrophy through suppression of PLA2G6 and DGK-ζ

This study aimed to observe the protective effect of momordicine I, a triterpenoid compound extracted from momordica charantia L., on isoproterenol (ISO)-induced hypertrophy in rat H9c2 cardiomyocytes and investigate its potential mechanism. Treatment with 10 μM ISO induced cardiomyocyte hypertrophy as evidenced by increased cell surface area and protein content as well as pronounced upregulation of fetal genes including atrial natriuretic peptide, β-myosin heavy chain, and α-skeletal actin; however, those responses were markedly attenuated by treatment with 12.5 μg/ml momordicine I. Transcriptome experiment results showed that there were 381 and 447 differentially expressed genes expressed in comparisons of model/control and momordicine I intervention/model, respectively. GO enrichment analysis suggested that the anti-cardiomyocyte hypertrophic effect of momordicine I may be mainly associated with the regulation of metabolic processes. Based on our transcriptome experiment results as well as literature reports, we selected glycerophospholipid metabolizing enzymes group VI phospholipase A₂ (PLA2G6) and diacylglycerol kinase ζ (DGK-ζ) as targets to further explore the potential mechanism through which momordicine I inhibited ISO-induced cardiomyocyte hypertrophy. Our results demonstrated that momordicine I inhibited ISO-induced upregulations of mRNA levels and protein expressions of PLA2G6 and DGK-ζ. Collectively, momordicine I alleviated ISO-induced cardiomyocyte hypertrophy, which may be related to its inhibition of the expression of glycerophospholipid metabolizing enzymes PLA2G6 and DGK-ζ.

Temporal lipid profiling in the progression from acute to chronic heart failure in mice and ischemic human hearts

BACKGROUND AND AIMS

Myocardial infarction (MI) is a leading cause of heart failure (HF). After MI, lipids undergo several phasic changes implicated in cardiac repair if inflammation resolves on time. However, if inflammation continues, that leads to end stage HF progression and development. Numerous studies have analyzed the traditional risk factors; however, temporal lipidomics data for human and animal models are limited. Thus, we aimed to obtain sequential lipid profiling from acute to chronic HF.

METHODS

Here, we report the comprehensive lipidome of the hearts from diseased and healthy subjects. To induce heart failure in mice, we used a non-reperfused model of coronary ligation, and MI was confirmed by echocardiography and histology, then temporal kinetics of lipids in different tissues (heart, spleen, kidney), and plasma was quantitated from heart failure mice and compared with naïve controls. For lipid analysis in mouse and human samples, untargeted liquid chromatography-linear trap quadrupole orbitrap mass spectrometry (LC-LTQ-Orbitrap MS) was performed.

RESULTS

In humans, multivariate analysis revealed distinct cardiac lipid profiles between healthy and ischemic subjects, with 16 lipid species significantly downregulated by 5-fold, mainly phosphatidylethanolamines (PE), in the ischemic heart. In contrast, PE levels were markedly increased in mouse tissues and plasma in chronic MI, indicating possible cardiac remodeling. Further, fold change analysis revealed site-specific lipid biomarkers for acute and chronic HF. A significant decrease in sulfatides (SHexCer (34:1; 2O)) and sphingomyelins (SM (d18:1/16:0)) was observed in mouse tissues and plasma in chronic HF.

CONCLUSIONS

Overall, a significant decreased lipidome in human ischemic LV and differential lipid metabolites in the transition of acute to chronic HF with inter-organ communication could provide novel insights into targeting integrative pathways for the early diagnosis or development of novel therapeutics to delay/prevent HF.