Abstract Body: Background: The global surge in cannabis use has driven the emergence of synthetic cannabinoids (SCs; e.g., CBN, HHC) as alternatives to natural cannabinoids (NCs; e.g., Δ9-THC, CBD). SCs, primarily chemically synthesized, circumvent regulations, raising concerns about their safety and physiological effects. Endothelial dysfunction, a key contributor to cardiovascular disease, may be differentially influenced by NCs and SCs, but their effects remain poorly understood. This study
Aims: To investigate the impact of NCs and SCs on endothelial function and barrier integrity using an iPSC-derived endothelial cell (iPSC-EC) model.
Approach: iPSC-ECs were generated from a healthy control and validated for the endothelial phenotype (PCAM1+, CDH5+, NOS3+) and functionality. Cells were treated with 5 µM NCs (Δ9-THC, CBD) or SCs (CBN, HHC) or vehicle control (VC) for 48 hours. Viability was not affected at this concentration (p>0.9999), and functional assays were performed, including wound healing, ROS production, nitric oxide (NO) levels, tube formation, and impedance measurements with thrombin stimulation (1 U/mL) to assess barrier integrity.
Results: NCs (Δ9-THC, CBD) significantly increased permeability, as evidenced by reduced impedance (normalized to VC |Z|=0.82±0.06 p=0.0127 and 0.79±0.03 p=0.025, respectively), while SCs) showed no significant effects (CBN 0.98±0.03, HHC 0.99±0.02). However, NCs exhibited distinct effects on other parameters: CBD reduced wound healing speed (0.82±0.03 p=0.0013), tube formation occupied area percentage (7.76±0.45 vs VC 10.05±0.54 p=0.0137), and ROS production (0.75±0.04 p=0.0004), while increasing basal NO levels (1.36±0.08 vs VC 0.85±0.07 p<0.0001), whereas Δ9-THC and SC counterpart HHC promoted increased tube formation (p<0.05). CBN had no significant impact on these functional assays.
Conclusion: These findings demonstrate that NCs and SCs exert distinct effects on endothelial function, with both NCs impairing barrier integrity but differentially influencing wound healing, tube formation, NO production, and ROS production. The shared effects of NCs in endothelial permeability, in contrast to SCs, highlight a critical area for future investigation into the pathways underlying these differential responses. This work provides a foundation for understanding the cardiovascular risks associated with cannabinoid use and informs the development of safer therapeutic agents targeting endothelial dysfunction.