Impact of myocardial reperfusion on human plasma lipidome

Lipidomics and cardiovascular disease

Cardiovascular diseases (CVDs) remain the leading cause of mortality worldwide, necessitating innovative approaches for early detection and personalized interventions. Lipidomics, leveraging advanced mass spectrometry techniques, has become instrumental in deciphering lipid-mediated mechanisms in CVDs. This review explores the application of lipidomics in identifying biomarkers for myocardial infarction, heart failure, stroke, and calcific aortic valve stenosis (CAVS). This review examines the technological advancements in shotgun lipidomics and LC/MS, which provide unparalleled insights into lipid composition and function. Key lipid biomarkers, including ceramides and lysophospholipids, have been linked to disease progression and therapeutic outcomes. Integrating lipidomics with genomic and proteomic data reveals the molecular underpinnings of CVDs, enhancing risk prediction and intervention strategies. This review positions lipidomics as a transformative tool in reshaping cardiovascular research and clinical practice.

Targeted circulating lipid mediators and immune cell gene transcripts after ST-elevation myocardial infarction

Residual inflammation drives atherogenesis to atherosclerosis and myocardial infarction, which triggers acute inflammation. In preclinical studies, polyunsaturated fatty acids-derived specialized pro-resolving mediators (SPMs) have been shown to promote recovery after myocardial infarction (MI), in contrast to proinflammatory lipid mediators (PIMs). However, the dynamic changes of lipid mediators after ST-elevation myocardial infarction (STEMI), particularly after percutaneous coronary intervention (PCI) and respective gene transcripts, are poorly understood. Therefore, the study aimed to assess the early dynamic changes in circulating lipid mediators and lipid pathway transcripts in patients with STEMI who undergo PCI. In this prospective observational clinical study, patients with STEMI (n = 10) and control subjects (n = 6) were included. Plasma samples for lipid mediator profiling (targeted oxylipids) and whole blood for inflammation-related transcript expression were collected at baseline before PCI, 2-, and 24-h post-PCI. A total of 10 patients with STEMI received PCI with a mean age of 53.3 yr, 90% male. Linoleic acid and docosapentaenoic acid levels were higher in patients with STEMI. A subset of PIM levels [hydroxyeicosatetraenoic acids, prostaglandin (PG)E2] was elevated at the baseline, with a subsequent decrease in circulating levels at 2 h after PCI [thromboxanes, leukotriene B4 (LTB4), 20-hydroxy-LTB4]. A subset of SPM levels was elevated at the baseline of STEMI suggestive overlap of inflammation-resolution signaling. The temporal kinetics of lipid mediators showed that both the initiation of inflammation and the resolution process start simultaneously and continue as an endogenous repair mechanism during STEMI. Therefore, approaches to increase these endogenous bioactive resolution mediators content and/or efficacy before PCI should be considered in treating patients with MI.NEW & NOTEWORTHY Polyunsaturated fatty acids-derived SPMs are decisive in myocardial infarction (MI) recovery, contrasting with proinflammatory lipid mediators (PIMs). A study on early lipid changes post-percutaneous coronary intervention (PCI) in patients with STEMI shows baseline elevation and post-PCI decrease in PIMs, whereas some SPM levels remain elevated. Findings highlight simultaneous inflammation and resolution in STEMI, emphasizing the need to enhance endogenous repair processes before PCI for better MI treatment.

A Lipidomics Approach to Determine the Role of Lipids and Its Crosstalk with Autophagy in Lung Cancer Metastasis

Non-small cell lung cancer (NSCLC) is among the most malignant tumors with high propensity for metastasis and is the leading cause of cancer-related death globally. Most patients present with regional and distant metastasis, associated with poor prognosis. Lipids may play an essential role in either activating or inhibiting detachment-induced apoptosis (anoikis), where the latter is a crucial mechanism to prevent metastasis, and it may have a cross-talk with autophagy. Autophagy has been shown to be induced in various human cancer metastasis, modulating tumor cell motility and invasion, cancer cell differentiation, resistance to anoikis, and epithelial to mesenchymal transition. Hence, it may play a crucial role in the transition of benign to malignant phenotypes, the core of metastasis initiation. Here, we provide a method we have established in our laboratory for detecting lipids in attached and detached non-small lung cancer cells and show how to analyze lipidomics data to find its correlation with autophagy-related pathways.

Highly reliable LC-MS lipidomics database for efficient human plasma profiling based on NIST SRM 1950

Liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS)-based methods have become the gold standard methodology for the comprehensive profiling of the human plasma lipidome. However, both the complexity of lipid chemistry and LC-HRMS-associated data pose challenges to the characterization of this biological matrix. In accordance with the current consensus of quality requirements for LC-HRMS lipidomics data, we aimed to characterize the NIST® Standard Reference Material for Human Plasma (SRM 1950) using an LC-ESI(+/-)-MS method compatible with high-throughput lipidome profiling. We generated a highly curated lipid database with increased coverage, quality, and consistency, including additional quality assurance procedures involving adduct formation, within-method m/z evaluation, retention behavior of species within lipid chain isomers, and expert-driven resolution of isomeric and isobaric interferences. As a proof-of-concept, we showed the utility of our in-house LC-MS lipidomic database -consisting of 592 lipid entries- for the fast, comprehensive, and reliable lipidomic profiling of the human plasma from healthy human volunteers. We are confident that the implementation of this robust resource and methodology will have a significant impact by reducing data redundancy and the current delays and bottlenecks in untargeted plasma lipidomic studies.

BCL2L13 Influences Autophagy and Ceramide Metabolism without Affecting Temozolomide Resistance in Glioblastoma

Temozolomide (TMZ) resistance in glioblastoma (GB) poses a significant therapeutic challenge. We developed a TMZ-resistant (TMZ-R) U251 GB model, revealing distinct differences in cell viability, apoptosis, autophagy, and lipid metabolism between TMZ-R and non-resistant (TMZ-NR) cells. TMZ-NR cells exhibited heightened sensitivity to TMZ-induced apoptosis, while TMZ-R cells-maintained viability. Autophagy flux was completely inhibited in TMZ-R cells, indicated by LC3βII and SQSTM1 accumulation. BCL2L13, which showed higher expression in TMZ-R cells, demonstrated increased interaction with Ceramide Synthase 6 (CerS6) and reduced interaction with Ceramide Synthase 2 (CerS2) in TMZ-NR cells. BCL2L13 knockdown (KD) disrupted autophagy flux, decreasing autophagosome accumulation in TMZ-R cells while increasing it in TMZ-NR cells. These changes contributed to altered ceramide profiles, where TMZ-R cells displayed elevated levels of Cer 16:0, 18:0, 20:0, 22:0, 24:0, and 24:1. Our findings highlight BCL2L13 and altered ceramide metabolism as potential therapeutic targets to overcome TMZ resistance in GB.

Sensory Neurons Release Cardioprotective Factors in an In Vitro Ischemia Model

Sensory neurons densely innervate the myocardium. The role of their sensing and response to acute and prolonged ischemia is largely unclear. In a cellular model of ischemia-reperfusion injury, the presence of sensory neurons increases cardiomyocyte survival. Here, after the exclusion of classical neurotransmitter release, and measurement of cytokine release, we modified the experiment from a direct co-culture of primary murine cardiomyocytes and sensory neurons to a transfer of the supernatant. Sensory neurons were exposed to ischemia and the resulting conditioned supernatant was transferred onto cardiomyocytes. This approach largely increased the tolerance of cardiomyocytes to ischemia and reperfusion. Towards the identification of the mechanism, it was demonstrated that after ten-fold dilution, the conditioned solution lost its protective effect. The effect remained after removal of extracellular vesicles by ultracentrifugation, and was not affected by exposure to protease activity, and fractionation pointed towards a hydrophilic agent. Solutions conditioned by HEK293t cells or 3T3 fibroblasts also increase cardiomyocyte survival, but to a lower degree. A metabolomic search identified 64 at least two-fold changed metabolites and lipids. Many of these could be identified and are involved in essential cellular functions. In the presented model for ischemia-reperfusion, sensory neurons secrete one or more cardioprotective substances that can improve cardiomyocyte survival.

Blood-Derived Lipid and Metabolite Biomarkers in Cardiovascular Research from Clinical Studies: A Recent Update

The primary prevention, early detection, and treatment of cardiovascular disease (CVD) have been long-standing scientific research goals worldwide. In the past decades, traditional blood lipid profiles have been routinely used in clinical practice to estimate the risk of CVDs such as atherosclerotic cardiovascular disease (ASCVD) and as treatment targets for the primary prevention of adverse cardiac events. These blood lipid panel tests often fail to fully predict all CVD risks and thus need to be improved. A comprehensive analysis of molecular species of lipids and metabolites (defined as lipidomics and metabolomics, respectively) can provide molecular insights into the pathophysiology of the disease and could serve as diagnostic and prognostic indicators of disease. Mass spectrometry (MS) and nuclear magnetic resonance (NMR)-based lipidomics and metabolomics analysis have been increasingly used to study the metabolic changes that occur during CVD pathogenesis. In this review, we provide an overview of various MS-based platforms and approaches that are commonly used in lipidomics and metabolomics workflows. This review summarizes the lipids and metabolites in human plasma/serum that have recently (from 2018 to December 2022) been identified as promising CVD biomarkers. In addition, this review describes the potential pathophysiological mechanisms associated with candidate CVD biomarkers. Future studies focused on these potential biomarkers and pathways will provide mechanistic clues of CVD pathogenesis and thus help with the risk assessment, diagnosis, and treatment of CVD.

Lipidomic Predictors of Coronary No-Reflow

The ‘no-reflow’ phenomenon (NRP) after primary percutaneous coronary intervention (PCI) is a serious complication among acute ST-segment elevation myocardial infarction (STEMI) patients. Herein, a comprehensive lipidomics approach was used to quantify over 300 distinct molecular species in circulating plasma from 126 patients with STEMI before and after primary PCI. Our analysis showed that three lipid classes: phosphatidylcholine (PC), alkylphosphatidylcholine (PC(O)), and sphingomyelin (SM), were significantly elevated (p < 0.05) in no-reflow patients before primary PCI. The levels of individual fatty acids and total fatty acid levels were significantly lower (p < 0.05) in no-reflow subjects after PCI. The grouping of patients based on ECG ST-segment resolution (STR) also demonstrated the same trend, confirming the possible role of these differential lipids in the setting of no-reflow. Sphingomyelin species, SM 41:1 and SM 41:2, was invariably positively correlated with corrected TIMI frame count (CTFC) at pre-PCI and post-PCI. The plasma levels of SM 42:1 exhibited an inverse association (p < 0.05) consistently with tumor necrosis factor-alpha (TNF-α) at pre-PCI and post-PCI. In conclusion, we identified plasma lipid profiles that distinguish individuals at risk of no-reflow and provided novel insights into how dyslipidemia may contribute to NRP after primary PCI.