Non-Psychoactive Phytocannabinoids Inhibit Inflammation-Related Changes of Human Coronary Artery Smooth Muscle and Endothelial Cells

Atherosclerosis is associated with vascular smooth muscle cell proliferation, chronic vascular inflammation, and leukocyte adhesion. In view of the cardioprotective effects of cannabinoids described in recent years, the present study investigated the impact of the non-psychoactive phytocannabinoids cannabidiol (CBD) and tetrahydrocannabivarin (THCV) on proliferation and migration of human coronary artery smooth muscle cells (HCASMC) and on inflammatory markers in human coronary artery endothelial cells (HCAEC). In HCASMC, CBD and THCV at nontoxic concentrations exhibited inhibitory effects on platelet-derived growth factor-triggered proliferation (CBD) and migration (CBD, THCV). When interleukin (IL)-1β- and lipopolysaccharide (LPS)-stimulated HCAEC were examined, both cannabinoids showed a concentration-dependent decrease in the expression of vascular cell adhesion molecule-1 (VCAM-1), which was mediated independently of classical cannabinoid receptors and was not accompanied by a comparable inhibition of intercellular adhesion molecule-1. Further inhibitor experiments demonstrated that reactive oxygen species, p38 mitogen-activated protein kinase activation, histone deacetylase, and nuclear factor κB (NF-κB) underlie IL-1β- and LPS-induced expression of VCAM-1. In this context, CBD and THCV were shown to inhibit phosphorylation of NF-κB regulators in LPS- but not IL-1β-stimulated HCAEC. Stimulation of HCAEC with IL-1β and LPS was associated with increased adhesion of monocytes, which, however, could not be significantly abolished by CBD and THCV. In summary, the results highlight the potential of the non-psychoactive cannabinoids CBD and THCV to regulate inflammation-related changes in HCASMC and HCAEC. Considering their effect on both cell types studied, further preclinical studies could address the use of CBD and THCV in drug-eluting stents for coronary interventions.