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Platelet ACKR3/CXCR7 surface expression is enhanced and influences prognosis in coronary artery disease (CAD) patients, who exhibit a distinct atherothrombotic platelet lipidome. Current investigation validates the potential of ACKR3/CXCR7 in regulating thromboinflammatory response through its impact on the platelet lipidome. CAD patients with enhanced platelet ACKR3/CXCR7 expression exhibited reduced aggregation. Pharmacological CXCR7 agonist (VUF11207) significantly reduced prothrombotic platelet response in blood from acute coronary syndrome patients ex vivo. CXCR7 agonist administration reduced thrombotic functions and thromboinflammatory plateletleukocyte interactions post–myocardial infarction and arterial injury in vivo. ACKR3/CXCR7 ligation did not affect surface availability of surface receptors, coagulation profile, bleeding time, plasma-dependent thrombin generation (thrombinoscopy), or clot formation (thromboelastography) but counteracted activation-induced phosphatidylserine exposure and procoagulant platelet-assisted thrombin generation. Targeted (micro-UHPLC-ESI-QTrap-MS/MS) and untargeted (UHPLCESI-QTOF-MS/MS) lipidomics analysis revealed that ACKR3/CXCR7 ligation favored generation of antithrombotic lipids (dihomo-γ-linolenic acid [DGLA], 12-hydroxyeicosatrienoic acid [12-HETrE]) over cyclooxygenase-1 (COX-1) or 12-lipoxygenase (12-LOX) metabolized prothrombotic and phospholipase-derived atherogenic lipids in healthy subjects and CAD patients, contrary to antiplatelet therapy. Through 12-HETrE, ACKR3/CXCR7 ligation coordinated with Gαs-coupled prostacyclin receptor to trigger cyclic adenosine monophosphate/protein kinase A–mediated platelet inhibition. ACKR3/CXCR7 ligation reduced generation of lipid agonists and lipid signaling intermediates, which affected calcium mobilization, intracellular signaling, and consequently platelet interaction with physiological matrices and thromboinflammatory secretome. This emphasized its functional dichotomy from prothrombotic CXCR4. Moreover, CXCR7 agonist regulated heparin-induced thrombocytopenia–sera/immunoglobulin G–triggered platelet and neutrophil activation, heparin-induced platelet aggregation, generation of thromboinflammatory lipids, platelet-neutrophil aggregate formation, and thromboinflammatory secretion ex vivo. Therefore, ACKR3/CXCR7 may offer a novel therapeutic strategy in acute/chronic thromboinflammation exaggerated cardiovascular pathologies and CAD.

Betulin is a pentacyclic triterpene with demonstrated healing properties in mid-dermal wounds. A few earlier studies have provided insights into the wound healing effects on the molecular level. However, there are still questions left on the molecular targets of betulin. Therefore, a pharmacolipidomics analysis of betulin is undertaken in human immortalized keratinocytes to monitor alterations in the lipid profiles induced by treatment with betulin. For this purpose, lipid extracts of keratinocytes treated with betulin and untreated controls are comprehensively analyzed by an untargeted UHPLC-ESI-QTOF-MS/MS lipidomics profiling workflow using data-independent acquisition. Targeted data processing allows the identification of 611 lipid species from 21 different lipid classes. Statistical analysis of the identified lipids shows significant changes in 440 lipid species that can be described as downregulation of cholesteryl esters and triacylglycerides and upregulation of glycerophospholipids, sphingolipids, and diacylglycerides. Additionally, some other signals corresponding to triterpenes are found in the betulin group and suggested that betulin is incorporated (in the membrane) and metabolized in keratinocytes.

Polyunsaturated fatty acids are important signaling molecules. A recent study reported hexadeca-4Z,7Z,10Z,13Z-tetraenoic acid, 12-oxo-5Z,8E,10E-heptadecatrienoic acid, and (12S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid as chemotherapy resistance-inducing factors when tumor cells were treated with cisplatin. Marine-based food supplements like fish oil or algae extracts are rich in polyunsaturated fatty acids and can contain large amounts of hexadeca-4Z,7Z,10Z,13Z-tetraenoic acid. Thus, it was concluded that oral uptake of hexadeca-4Z,7Z,10Z,13Z-tetraenoic acid might induce chemoresistance as shown in a mouse model. Cancer patients tend to consume food supplements containing polyunsaturated fatty acids on a regular basis. The uptake of hexadeca-4Z,7Z,10Z,13Z-tetraenoic acid and (12S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid should be controlled, because even low concentrations of 0.5 ng mL-1 showed chemoresistance-inducing effects in animal experiments. For accurate analysis of hexadeca-4Z,7Z,10Z,13Z-tetraenoic acid and (12S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid a validated method was developed by using ultrahigh-performance liquid chromatography hyphenated to quadrupole time of flight mass spectrometry via electrospray ionization and sample preparation by solid-phase extraction (SPE) with 3-aminopropyl silica. A combined targeted/untargeted approach was utilized using MS/MS by data-independent acquisition with SWATH and applied to commercial food supplements (refined fish oil, fish oil capsules, algae oil capsules, and flaxseed capsules). Accurate quantification of hexadeca-4Z,7Z,10Z,13Z-tetraenoic acid and (12S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid on the MS/MS level with simultaneous untargeted fatty acid screening revealed additional information. The LODs for hexadeca-4Z,7Z,10Z,13Z-tetraenoic acid and (12S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid were 0.036 ng mL-1 and 0.054 ng mL-1, respectively. Since hexadeca-4Z,7Z,10Z,13Z-tetraenoic acid was present in the samples in large amounts and (12S)-hydroxy-5Z,8E,10E-heptadecatrienoic was not expected to be present in high concentrations, two calibration ranges, namely, 0.5–20 ng mL-1 and 5–200 ng mL-1, were validated. An untargeted screening identified 18–39 free fatty acids being present in the lipid extracts of the food supplement samples.