In Vitro Effects of Cannabidiol on Activated Immune-Inflammatory Pathways in Major Depressive Patients and Healthy Controls

Major depressive disorder and major depressive episodes (MDD/MDE) are characterized by the activation of the immune-inflammatory response system (IRS) and the compensatory immune-regulatory system (CIRS). Cannabidiol (CBD) is a phytocannabinoid isolated from the cannabis plant, which is reported to have antidepressant-like and anti-inflammatory effects. The aim of the present study is to examine the effects of CBD on IRS, CIRS, M1, T helper (Th)-1, Th-2, Th-17, T regulatory (Treg) profiles, and growth factors in depression and healthy controls. Culture supernatant of stimulated (5 mu g/mL of PHA and 25 mu g/mL of LPS) whole blood of 30 depressed patients and 20 controls was assayed for cytokines using the LUMINEX assay. The effects of three CBD concentrations (0.1 mu g/mL, 1 mu g/mL, and 10 mu g/mL) were examined. Depression was characterized by significantly increased PHA + LPS-stimulated Th-1, Th-2, Th-17, Treg, IRS, CIRS, and neurotoxicity profiles. CBD 0.1 mu g/mL did not have any immune effects. CBD 1.0 mu g/mL decreased CIRS activities but increased growth factor production, while CBD 10.0 mu g/mL suppressed Th-1, Th-17, IRS, CIRS, and a neurotoxicity profile and enhanced T cell growth and growth factor production. CBD 1.0 to 10.0 mu g/mL dose-dependently decreased sIL-1RA, IL-8, IL-9, IL-10, IL-13, CCL11, G-CSF, IFN-gamma, CCL2, CCL4, and CCL5, and increased IL-1 beta, IL-4, IL-15, IL-17, GM-CSF, TNF-alpha, FGF, and VEGF. In summary, in this experiment, there was no beneficial effect of CBD on the activated immune profile of depression and higher CBD concentrations can worsen inflammatory processes.

Automated summary

This study examines the effects of cannabidiol (CBD) on the immune-inflammatory response and immune-regulatory system in patients with depression and healthy controls. The results suggest that higher concentrations of CBD may worsen inflammatory processes.