Cannabidiol, CBD is a cannabinoid found in cannabis plant material. It is a major constituent of the plant. According to Raphael Mechoulam of the Hebrew University, Faculty of Medicine. CBD increases wakefulness and decreases REM sleep. CBD is known to have anti-nausea and anti-inflammatory effects.
CBD occurs in almost all varieties of cannabis but is more prvailant in certain strainsbeing developed for medical use. It has ben shown to be analgesic and have antibiotic properties. It interacts with THC to down-regulate psycho activity. and potentates the depressant effects of THC. It delays the onset of the psychoactive experience and extends the duration of the effects of the high.
Recent studies and clinical trials show that it relieves convulsion, inflammation, anxiety, and nausea. Cannabidiol has also been shown effective as atypical anti-psychotics in treating schizophrenia.
An international land mark study titled: Non-psychotropic plant cannabinoids: new therapeutic opportunities from an ancient herb shows that cannabis contains many cannabinoids with weak or no psychoactivity that therapeutically, may be more promising than THC. In that study, researchers provide an overview of the recent pharmacological advances, mechanisms of action, and potential therapeutic applications of cannabinoids. described on the chart below.
In this study, special emphasis was given to cannabidiol CBD for possible applications for inflammation, diabetes, cancer, affective and neurodegenerative diseases, and to D9 tetrahydrocannabivarin THCV, a novel CB1 antagonist which exerts potentially useful actions in the treatment of epilepsy and obesity.
A brief summary findings for Cancer
D9-THC, CBD, CBG, CBC, D9-THCA and CBDA have been shown to exert anti-proliferative/pro-apoptotic effects (IC50 in the range 5–25 mM) in a panel of tumor cell lines: human breast carcinoma, human prostate carcinoma, human colorectal carcinoma, human gastric adeno carcinoma, C6 rat glioma, rat basophilic leukemia and transformed thyroid cells. CBD exhibited the highest potency with IC50 values between 6 mM and 10.6 mM, and maximal efficacy at 25 mM, followed by CBG and CBC . CBDA was the least effective compound, being active against only breast, thyroid and glioma cells. Furthermore, prostate carcinoma cells were found to be quite resistant to the action of phytocannabinoids, with only CBD and CBG exerting anti-proliferative effects . More in-depth studies showed that CBD inhibited glioma, leukaemia and breast cancer, as detailed below.
CBD exerted cannabinoid-independent anti-metastatic and pro-apoptotic effects on human glioma cells and tumor regression in vivo [1,7,27]. CBD-induced apoptosis of human glioma cells involves early production of ROS and concomitant activation of initiator caspase-8 and caspase-9, converging into the activation of the downstream effector caspase-3 . In vivo, CBD induced glioma growth inhibition through specific modulation of the pro-carcinogenic LOX pathway .
CBD induced a CB2-mediated reduction in viability and apoptosis in leukemia cells, and reduced tumor burden and increased the number of apoptotic tumours in EL-4-bearing mice in vivo; the effect was associated with increased production of ROS, which was mediated through regulation of Nox4 and p22phox .
CBD inhibited the growth of xenograft tumours obtained by subcutaneous injection of human breast carcinoma cells into athymic mice . Studies investigating the mode of action showed that CBD down-regulated the expression of Id-1 (a key regulator of the metastatic potential of breast and other carcinomas) in metastatic human breast cancer cells, leading to reduction of tumour aggressiveness .
Phytocannabinoids have been shown to inhibit ATPbinding cassette (ABC) transporters, which play a part in the multi-drug resistance of tumor cells. Specifically, P-glycoprotein (ABCB1) was inhibited by CBD, but not by D9-THCV, D9-THCA or CBN ; multi-drug resistance related protein 1 (ABCC1/MRP1) and breast cancer resistance protein were inhibited by CBD, CBN and D9-THC (order of potency: CBD > CBN > D9-THC) .
CBD was shown to attenuate oxidative/nitrosative stress, inflammation, and cell death induced by the anticancer drug cisplatin in the mouse kidney . Nephrotoxicity is a common complication of cisplatin chemotherapy, which limits its clinical use. In summary, the phytocannabinoids CBD,CBG, and CBC have shown interesting pro-apoptotic properties in cancer cell lines. The most studied phytocannabinoid is CBD. CBD induces increases in [Ca2+]i, thereby stimulating ROS production and causing apoptosis. In vivo, CBD inhibits glioma growth and experimental breast carcinoma.