Ruete, M. C. | Search bioRxiv

bioRxiv2026

Purified CBD and CBD-rich full-spectrum Cannabis sativa extract potentiate the angiogenic paracrine function of umbilical cord derived mesenchymal stem cells

BackgroundChronic and non-healing wounds remain a major clinical challenge with limited therapeutic options. Angiogenesis and inflammation are central to tissue repair, and mesenchymal stem cells (MSC) contribute to these processes through their trophic and immunomodulatory secretome. Cannabidiol (CBD) exhibits antioxidant and immunomodulatory properties. However, whether CBD-rich Cannabis sativa extract stimulate MSC toward a pro-angiogenic secretome remains unclear. PurposeThis study aims to determine whether purified CBD or a phytochemically CBD-rich full spectrum extract stimulate umbilical cord-derived human MSC (UC-hMSC) to secrete pro-angiogenic factors and enhance endothelial responses relevant to wound healing. MethodsUC-hMSC were preconditioned with either purified CBD or a CBD-rich full-spectrum extract. Transcriptional changes were assessed by qPCR. The functional impact of the resulting secretomes was evaluated in vitro using HUVEC-based proliferation and tube formation assays, and in vivo through the chick chorioallantoic membrane assay. To explore underlying mechanisms, we examined HIF-1 stabilization and VEGFA release in UC-hMSC, and VEGFR-2/ERK signaling in HUVEC. ResultsPurified CBD and full-spectrum CBD extract preconditioned UC-hMSC secretomes, increased HUVEC proliferation, tube formation, and enhanced vascular branching in the CAM assay. Mechanistic analyses indicated activation of the HIF-1/VEGF axis in UC-hMSC, and ERK1/2 activation in HUVEC that was sensitive to VEGFR-2 blockade. ConclusionPurified CBD and CBD-rich full-spectrum extract prime UC-hMSC toward a pro-angiogenic secretome that promotes endothelial activation and neovascularization. These findings suggest that cannabinoid-based preconditioning of UC-hMSC involves the HIF-1/VEGF axis and VEGFR-2/ERK signaling pathways in endothelial cells, supporting further investigation of this approach in wound healing and regenerative therapies.

cell biology↗

bioRxiv2022

The molecular chaperone Cysteine String Protein is required to stabilize trans-SNARE complexes during human sperm acrosomal exocytosis

Membrane fusion in sperm cells is crucial for acrosomal exocytosis and must be preserved to assure fertilizing capacity. Evolutionarily conserved protein machinery regulates acrosomal exocytosis. Molecular chaperones play a vital role in spermatogenesis and post-testicular maturation. Cysteine String Protein (CSP) is a member of the Hsp40 co-chaperones, and for more than 20 years, most research published focused on CSPs role in synapsis. However, the participation of molecular chaperones in acrosomal exocytosis is poorly understood. Using western blot and indirect immunofluorescence, we showed that CSP is present in human sperm, is predominantly bound to membranes, and is palmitoylated. Moreover, using electron microscopy and functional assays, we reported that sequestration of CSP avoided the assembly of trans-complexes and inhibited exocytosis. In summary, our data demonstrated that CSP is necessary and mediates the trans-SNARE complex assembly between the outer acrosomal and plasma membranes, thereby regulating human sperm acrosomal exocytosis. Understanding CSPs role is critical in identifying new biomarkers and generating new rational-based approaches to treating male infertility. Summary statementCysteine String Protein is necessary and mediates the trans-SNARE complex assembly between the outer acrosomal and plasma membranes, thereby regulating human sperm acrosomal exocytosis.

cell biology↗