Abstract
We have previously reported that Δ(9)-tetrahydrocannabinol (Δ(9)-THC), the main psychoactive cannabinoid in marijuana, suppresses CD40 ligand (CD40L) expression by activated mouse CD4(+) T cells. CD40L is involved in pathogenesis of many autoimmune and inflammatory diseases. In the present study, we investigated the molecular mechanism of Δ(9)-THC-mediated suppression of CD40L expression using peripheral blood human T cells. Pretreatment with Δ(9)-THC attenuated CD40L expression in human CD4(+) T cells activated by anti-CD3/CD28 at both the protein and mRNA level, as determined by flow cytometry and quantitative real-time PCR, respectively. Electrophoretic mobility shift assays revealed that Δ(9)-THC suppressed the DNA-binding activity of both NFAT and NFκB to their respective response elements within the CD40L promoter. An assessment of the effect of Δ(9)-THC on proximal T cell-receptor (TCR) signaling induced by anti-CD3/CD28 showed significant impairment in the rise of intracellular calcium, but no significant effect on the phosphorylation of ZAP70, PLCγ1/2, Akt, and GSK3β. Collectively, these findings identify perturbation of the calcium-NFAT and NFκB signaling cascade as a key mechanistic event by which Δ(9)-THC suppresses human T cell function.
Keywords:
CD40L; Intracellular calcium; NFAT; NFκB; T cell-receptor signaling; Δ(9)-tetrahydrocannabinol (Δ(9)-THC).
© 2013.
Publication types
-
Research Support, N.I.H., Extramural
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Animals
-
CD28 Antigens / metabolism
-
CD4-Positive T-Lymphocytes / cytology
-
CD4-Positive T-Lymphocytes / drug effects*
-
CD4-Positive T-Lymphocytes / metabolism
-
CD40 Ligand / antagonists & inhibitors
-
CD40 Ligand / genetics*
-
CD40 Ligand / metabolism
-
Calcium / analysis
-
Cannabinoids / chemistry
-
Dronabinol / pharmacology*
-
Female
-
Flow Cytometry
-
Gene Expression Regulation
-
Glycogen Synthase Kinase 3 / genetics
-
Glycogen Synthase Kinase 3 / metabolism
-
Glycogen Synthase Kinase 3 beta
-
Humans
-
Leukocytes, Mononuclear / cytology
-
Leukocytes, Mononuclear / drug effects
-
Mice
-
Mice, Inbred C57BL
-
NF-kappa B / antagonists & inhibitors
-
NF-kappa B / genetics*
-
NF-kappa B / metabolism
-
NFATC Transcription Factors / antagonists & inhibitors
-
NFATC Transcription Factors / genetics*
-
NFATC Transcription Factors / metabolism
-
Phospholipase C gamma / genetics
-
Phospholipase C gamma / metabolism
-
Phosphorylation
-
Proto-Oncogene Proteins c-akt / genetics
-
Proto-Oncogene Proteins c-akt / metabolism
-
Real-Time Polymerase Chain Reaction
-
Signal Transduction
-
ZAP-70 Protein-Tyrosine Kinase / genetics
-
ZAP-70 Protein-Tyrosine Kinase / metabolism
Substances
-
CD28 Antigens
-
Cannabinoids
-
NF-kappa B
-
NFATC Transcription Factors
-
CD40 Ligand
-
Dronabinol
-
ZAP-70 Protein-Tyrosine Kinase
-
ZAP70 protein, human
-
GSK3B protein, human
-
Glycogen Synthase Kinase 3 beta
-
Gsk3b protein, mouse
-
Proto-Oncogene Proteins c-akt
-
Glycogen Synthase Kinase 3
-
Phospholipase C gamma
-
Calcium