Efficient megakaryopoiesis and platelet production require phospholipid remodeling and PUFA uptake through CD36

Platelet lipidomics and de novo lipogenesis: impact on health and disease

PURPOSE OF REVIEW

Lipids play vital roles in platelet structure, signaling, and metabolism. In addition to capturing exogenous lipids, platelets possess the capacity for de novo lipogenesis, regulated by acetyl-coA carboxylase 1 (ACC1). This review aims to cover the critical roles of platelet de novo lipogenesis and lipidome in platelet production, function, and diseases.

RECENT FINDINGS

Upon platelet activation, approximately 20% of the platelet lipidome undergoes significant modifications, primarily affecting arachidonic acid-containing species. Multiple studies emphasize the impact of de novo lipogenesis, with ACC1 as key player, on platelet functions. Mouse models suggest the importance of the AMPK-ACC1 axis in regulating platelet membrane arachidonic acid content, associated with TXA 2 secretion, and thrombus formation. In human platelets, ACC1 inhibition leads to reduced platelet reactivity. Remodeling of the platelet lipidome, alongside with de novo lipogenesis, is also crucial for platelet biogenesis. Disruptions in the platelet lipidome are observed in various pathological conditions, including cardiovascular and inflammatory diseases, with associations between these alterations and shifts in platelet reactivity highlighted.

SUMMARY

The platelet lipidome, partially regulated by ACC-driven de novo lipogenesis, is indispensable for platelet production and function. It is implicated in various pathological conditions involving platelets.

Metabolomics profile and machine learning prediction of treatment responses in immune thrombocytopenia: A prospective cohort study

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by antibody-mediated platelet destruction and impaired platelet production. The mechanisms underlying ITP and biomarkers predicting the response of drug treatments are elusive. We performed a metabolomic profiling of bone marrow biopsy samples collected from ITP patients admission in a prospective study of the National Longitudinal Cohort of Hematological Diseases. Machine learning algorithms were conducted to discover novel biomarkers to predict ITP patient treatment responses. From the bone marrow biopsies of 91 ITP patients, we quantified a total of 4494 metabolites, including 1456 metabolites in the positive mode and 3038 metabolites in the negative mode. Metabolic patterns varied significantly between groups of newly diagnosed and chronic ITP, with a total of 876 differential metabolites involved in 181 unique metabolic pathways. Enrichment factors and p-values revealed the top metabolically enriched pathways to be sphingolipid metabolism, the sphingolipid signalling pathway, ubiquinone and other terpenoid-quinone biosynthesis, thiamine metabolism, tryptophan metabolism and cofactors biosynthesis, the phospholipase D signalling pathway and the phosphatidylinositol signalling system. Based on patient responses to five treatment options, we screened several metabolites using the Boruta algorithm and ranked their importance using the random forest algorithm. Lipids and their metabolism, including long-chain fatty acids, oxidized lipids, glycerophospholipids, phosphatidylcholine and phosphatidylethanolamine biosynthesis, helped differentiate drug treatment responses. In conclusion, this study revealed metabolic alterations associated with ITP in bone marrow supernatants and a potential biomarker predicting the response to ITP.

Immunometabolism in atherosclerotic disorders

Cardiovascular diseases (CVDs), including atherosclerosis, myocardial infarction and heart failure, are the leading causes of morbidity and mortality worldwide. Emerging evidence suggests a crucial role for immune cell dysfunction and inflammation in the progression of this complex set of diseases. Recent advances demonstrate that immune cells, tightly linked to CVD pathogenesis, are sensitive to environmental signals and respond by engaging immunometabolic networks that shape their behavior. Inflammatory cues and altered nutrient availability within atherosclerotic plaques or following ischemia synergize to elicit metabolic shifts in immune cells that influence the course of disease pathology. Understanding these metabolic adaptations and how they contribute to cellular dysfunction may reveal novel therapeutic approaches for the treatment of CVD. Here we provide a comprehensive summary of the metabolic reprogramming that occurs in immune cells and their progenitors during CVD, offering insights into the potential therapeutic interventions to mitigate disease progression.

Ferroptosis-Regulated Cell Death as a Therapeutic Strategy for Neurodegenerative Diseases: Current Status and Future Prospects

Ferroptosis is increasingly being recognized as a key element in the pathogenesis of diverse diseases. Recent studies have highlighted the intricate links between iron metabolism and neurodegenerative disorders. Emerging evidence suggests that iron homeostasis, oxidative stress, and neuroinflammation all contribute to the regulation of both ferroptosis and neuronal health. However, the precise molecular mechanisms underlying the involvement of ferroptosis in the pathological processes of neurodegeneration and its impact on neuronal dysfunction remain incompletely understood. In our Review, we provide a comprehensive analysis and summary of the potential molecular mechanisms underlying ferroptosis in neurodegenerative diseases, aiming to elucidate the disease progression of neurodegeneration. Additionally, we discuss potential therapeutic agents that modulate ferroptosis with the goal of identifying novel drug molecules for the treatment of neurodegenerative disorders.

Lipid remodeling in megakaryocyte differentiation and platelet biogenesis

Lipid remodeling, from fatty acid transport and de novo lipid synthesis, is necessary for megakaryocyte differentiation and platelet production. Dietary saturated fatty acids, impaired fatty acid transport and/or dysfunction in lipid biogenesis can contribute to low platelet counts.