Abstract Background GLP-1 receptor agonists (GLP-1RAs) are key therapeutics in type 2 diabetes management, offering benefits beyond glycemic control, including cardiovascular protection. Hematopoietic stem cells (HSCs) contribute to chronic cardiovascular inflammation via trained immunity. We recently demonstrated that human HSCs express GLP-1R, and GLP-1RAs are being explored for their immunomodulatory potential. However, their effects on HSC lineage commitment and maturation remain unclear. Purpose To characterize the molecular response of human HSCs following liraglutide (LIRA) stimulation. Methods CD34+ hematopoietic stem/progenitor cells (HSPCs) from three healthy cord blood donors were cultured in StemSpam medium ± LIRA (100nM) for 10 days. Single-cell RNA sequencing (scRNA-seq) was performed using the 10x Genomics Chromium platform. Data processing involved CellRanger for unique molecular identifier (UMI) quantification and Seurat for downstream analysis (cells with 200–5000 genes, 5% mitochondrial UMIs). Cell clustering and type identification were conducted via DaMiRseq, LIMMA, EnrichR, and CellXgene. Differential expression analysis and pathway enrichment (Gene Ontology Biological Process, GOBP) were performed using DaMiRseq, LIMMA, and Gene Set Enrichment Analysis (GSEA). Trajectory and cell-cell communication analyses were performed by CellPhoneDB and slingshot, respectively. Results The transcriptome analysis at cell scale identified 18 distinct hematopoietic cell clusters in both control and LIRA-treated HSCs that were representative of the main hematopoietic cell lineages, highlighting cell-type at different stages of maturation. Differential gene expression analysis revealed that LIRA influenced progenitor cell commitment, decreasing monocyte and lymphocyte populations while increasing granulocyte and megakaryocyte lineages. Notably, LIRA treatment also induced an expansion of previously uncharacterized leukocyte populations. Transcriptional analysis demonstrated significant downregulation of biological processes related to cellular respiration (e.g., GO:0006119, GO:0042775) and inflammatory response (GO:0006954, GO:0002526). Finally, ‘cell-cell communication’ and ‘trajectory analysis’ indicated altered cellular interactions, especially related to angiogenesis and immune response signaling, and delayed lineage differentiation in LIRA-treated cells. Conclusion scRNA-seq analysis suggests that LIRA modulates and delays progenitor cell differentiation, implying an immunomodulatory effect that may contribute to GLP-1RA mediated cardiovascular protection.
Damiano et al. (Sat,) studied this question.