CBD Treatment Improves Fatal Inflammatory Response Exhibited in SEB-Induced ARDS

ABSTRACT

The novel SARS-CoV-2 virus known to cause the COVID-19 outbreak has resulted in a global healthcare crisis that has persisted the past 3 years. Thus, understanding the mechanisms underlying this disease are vital at this time. While there are issues of research infrastructure to handle the virus and because of the refractoriness of rodents to this disease, the availability of these tools is still limited. The cytokine storm and fatality presented in patients with severe COVID-19 can be mimicked with Staphylococcal enterotoxin B (SEB)-induced Acute Respiratory Distress Syndrome (ARDS). Within ~7 days, the survival rate drops to 0% for C3H/HeJ mice exposed to a dual dose of SEB. In this study, we administered cannabidiol (CBD) intraperitoneally for 3 days pre- and post-SEB dosing and found that the clinical outcomes improved significantly. Initial evaluation of scRNASeq data from lungs comparing naive to SEB-induced ARDS mice illustrated an increase in infiltrating immune cells, and a loss in pulmonary epithelial cells in the latter group. When evaluating the effect of CBD treatment on SEB-induced ARDS, we were able to demonstrate that CBD reduced the macrophage population. To characterize the mechanism by which CBD treatment ameliorated the inflammatory response, we found that CBD treated mice had significant reduction in infiltrating immune cells and alveolar thickening. This same histology and infiltration is presented in ARDS. MicroRNA expression analysis showed a significant increase in the expression mmu-miR-298-5p and mmu-miR- 566 with CBD treatment. Ingenuity Pathway Analysis (IPA) indicated that the dysregulated miRNAs were also implicated in pathways associated with macrophage activation, respiratory disease and inflammation, interferon stimulated genes, as well as genes which have been upregulated in the disease state of this model. These targets include but are not limited to Cebpb, Efhd2, Stat3, Socs3, Cxcl5, Gbp2, and Birc3. This finding offers insights for the development of preventive and therapeutic strategies in the treatment of ARDS, including that induced in COVID-19. Supported by NIH grants P01AT003961, P20GM103641, R01ES003961, R01AI129788, R01AI123947, R01AI160896 to MN and PSN and K99GM147910 to KW.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.