Study: Non-Psychoactive Plant Cannabinoids Possess Synergistic Anti-Cancer Activity In Leukemia Cell LinesOctober 15, 2013
The concomitant administration of various non-psychoactive plant cannabinoids demonstrates synergistic anti-cancer activity in human leukemia cells, according to preclinical trial data published online this week in the journal Anticancer Research.
Investigators from Saint George’s, University of London assessed the anti-cancer potential of three non-psychoactive cannabinoids (cannabidiol, cannabigerol, and cannabigevarin) and their respective acids on two types of leukaemia cell lines. Authors reported that the administration of cannabinoids in concert with one another resulted in “in additive/mildly synergistic interaction.”
They concluded: “Our findings indicate that cannabinoids act with each other in a way such that doses for therapy could be reduced without a significant loss of activity. … [T]his study adds further support to the idea that cannabinoids can have a role in the cancer setting, not only as single agents, but also in combination with each other.”
Commenting on the study in a press release, lead author Wai Lui said: “These agents are able to interfere with the development of cancerous cells, stopping them in their tracks and preventing them from growing. In some cases, by using specific dosage patterns, they can destroy cancer cells on their own. Used in combination with existing treatment, we could discover some highly effective strategies for tackling cancer. Significantly, these compounds are inexpensive to produce and making better use of their unique properties could result in much more cost effective anti-cancer drugs in future.”
Plant cannabinoids as well as endogenous cannabinoids have been consistently shown to be potent anti-cancer inhibitors in preclinical models, halting the proliferation of glioma cancer cells, prostate cancer cells, breast carcinoma, lung carcinoma, and lymphoma, among other cancer cell lines. NORML’s review of much of this literature appears online here.
An abstract of the study, “Enhancing the activity of cannabidiol and other cannabinoids in vitro through modifications to drug combinations and treatment schedules,” appears online here.
Republican Gov. Chris Christie has signed legislation, Senate Bill 2842, into law modifying aspects of the state’s medical marijuana regulations.
Specifically, the law amends requirements that state-licensed medical cannabis producers and distributors be limited to providing patients with no more than three strains of the plant – a regulatory rule that has been in place since the program’s inception some three years ago. Proponents of the rule change argued that lifting the three-strain cap will foster the production and distribution of varieties of cannabis high in CBD (cannabidiol) content. Cannabidiol is a non-psychotropic cannabinoid that possesses a variety of therapeutic properties. However, it is typically present at relatively low levels in conventional strains of marijuana, which typically are bred to possess higher quantities of THC – the primary psychoactive ingredient in cannabis.
Senate Bill 2842 also allows for cannabis distributors to produce marijuana-infused edible products. However, at the insistence of the Governor, consumption of such products will be limited to those age 18 and younger.
Governor Christie previously vetoed language that sought to streamline regulations so that qualified patients under the age of 18 could more readily access medicinal cannabis.
Under present New Jersey law, authorized patients may only obtain medical cannabis from state-licensed dispensaries. To date, however, few facilities are actively up and running. Earlier this month, the state’s Economic Developmental Authority approved a $375,000 loan to the Compassionate Care Foundation dispensary, which plans to open its doors in mid-October.
The inhalation of the non-psychoactive cannabinoid CBD (cannabidiol) significantly mitigates tobacco smokers’ desire for cigarettes, according to clinical trial data published online in the journal Addictive Behaviors.
Investigators at University College London conducted a double blind pilot study to assess the impact of the ad-hoc consumption of organic CBD versus placebo in 24 tobacco-smoking subjects seeking to quit their habit. Participants were randomized to receive an inhaler containing CBD (n=12) or placebo (n=12) for one week. Trial investigators instructed subjects to use the inhaler when they felt the urge to smoke.
Researchers reported: “Over the treatment week, placebo treated smokers showed no differences in number of cigarettes smoked. In contrast, those treated with CBD significantly reduced the number of cigarettes smoked by [the equivalent of] 40 percent during treatment.” Moreover, participants who used CBD did not report experiencing increased cravings for nicotine during the study’s duration.
Investigators concluded, “This is the first study, as far as we are aware, to demonstrate the impact of CBD on cigarette smoking. … These preliminary data, combined with the strong preclinical rationale for use of this compound, suggest CBD to be a potential treatment for nicotine addiction that warrants further exploration.”
Previously published clinical trials on CBD have found cannabidiol to be “safe and well tolerated” in healthy volunteers.
Separate investigations of CBD have documented the cannabinoid to possess a variety of therapeutic properties, including anti-inflammatory, anti-diabetic, anti-epileptic, anti-cancer, and bone-stimulating properties.
Full text of the study, “Cannabidiol reduces cigarette consumption in tobacco smokers: Preliminary findings,” appears online in the journal Addictive Behaviors.
Preclinical study data published online in the scientific journal Nutrition & Diabetes reports that tetrahydrocannabivarin (THCV) — a naturally occurring analogue of THC — possesses positive metabolic effects in animal models of obesity.
British researchers assessed the effects of THCV administration on dietary-induced and genetically modified obese mice. Authors reported that although THCV administration did not significantly affect food intake or body weight gain in any of the models, it did produce several metabolically beneficial effects, including reduced glucose intolerance, improved glucose tolerance, improved liver triglyceride levels, and increased insulin sensitivity.
Researchers concluded: “Based on these data, it can be suggested that THCV may be useful for the treatment of the metabolic syndrome and/or type 2 diabetes (adult onset diabetes), either alone or in combination with existing treatments. Given the reported benefits of another non-THC cannabinoid, CBD in type 1 diabetes, a CBD/THCV combination may be beneficial for different types of diabetes mellitus.”
Last month, Harvard Medical School researchers published observational data in The American Journal of Medicine reporting that subjects who regularly consume cannabis possess favorable indices related to diabetic control as compared to occasional consumers or non-users of the substance. Writing in an accompanying commentary, the journal’s Editor-in-Chief stated: “These are indeed remarkable observations that are supported, as the authors note, by basic science experiments that came to similar conclusions. … I would like to call on the NIH and the DEA to collaborate in developing policies to implement solid scientific investigations that would lead to information assisting physicians in the proper use and prescription of THC in its synthetic or herbal form.”
Observational trial data published in 2012 in the British Medical Journal previously reported that adults with a history of marijuana use had a lower prevalence of type 2 diabetes and possess a lower risk of contracting the disease than did those with no history of cannabis consumption, even after researchers adjusted for social variables such as subjects’ ethnicity and levels of physical activity.
Full text of the study, “The cannabinoid ?9-tetrahydrocannabivarin (THCV) ameliorates insulin sensitivity in two mouse models of obesity,” is available online here.
Recent preclinical studies published over the past several weeks provide further evidence that cannabinoids are both neuroprotective and cardioprotective.
A May 30th blog post on the website Science20.com sums up new findings from Israel regarding the ability of low doses of THC to prevent brain damage in animals.
Prof. Yosef Sarne in the Department of Physiology and Pharmacology at Tel Aviv University says that [cannabis] … has neuroprotective qualities. He has found that extremely low doses of THC — the psychoactive component of marijuana — protects the brain from long-term cognitive damage in the wake of injury from hypoxia (lack of oxygen), seizures, or toxic drugs.
Previous studies focused on injecting high doses of THC within a very short time frame – approximately 30 minutes – before or after injury. Sarne’s papers in Behavioural Brain Research and Experimental Brain Research say that even extremely low doses of THC – around 1,000 to 10,000 times less than that in a conventional marijuana cigarette – administered over a wide window of 1 to 7 days before or 1 to 3 days after injury can jump-start biochemical processes which protect brain cells and preserve cognitive function over time.
… In the lab, the researchers injected mice with a single low dose of THC either before or after exposing them to brain trauma. A control group of mice sustained brain injury but did not receive the THC treatment. When the mice were examined 3 to 7 weeks after initial injury, recipients of the THC treatment performed better in behavioral tests measuring learning and memory. Additionally, biochemical studies showed heightened amounts of neuroprotective chemicals in the treatment group compared to the control group.
… This treatment, especially in light of the long time frame for administration and the low dosage, could be applicable to many cases of brain injury and be safer over time, Sarne says.
NORML has previously reported on separate preclinical data documenting that cannabinoids can promote neurogenesis (the active production of new neurons) in laboratory animals as well observational data indicating that marijuana may provide neuroprotection against alcohol-induced impairment in adolescent subjects.
In addition, recently published preclinical studies also indicate that cannabinoids may offer benefits to the heart. Animal data published in the June issue of the scientific journal Biochemical Pharmacology reports that THC administration “is a safe and effective treatment that reduces myocardial ischemic (heart attack) damage.” Authors concluded: “[O]ur study provides novel evidence for the beneficial use of extremely low doses of THC, doses that do not elicit any psychoactive side effects, in order to protect the heart from ischemic insults. THC can be used as a pre-conditioning drug in cases in which ischemic insult to the heart is anticipated, such as during cardiac surgery or percutaneous coronary intervention. If post-conditioning with THC will be found effective, it could also be used following myocardial infarction.”
The results of a separate preclinical trial, published in May in the journal Environmental Toxicology and Pharmacology, report that the administration of the non-psychotropic cannabinoid cannabidiol (CBD) is protective against cardiotoxicity in rats. “[C]annabidiol ameliorated doxorubicin-induced cardiac injury,” the study concluded. “These results indicate that cannabidiol represents a potential protective agent.”
In February of this year, investigators at the Bar-Ilan University in Israel also reported that the administration of delta-9-THC protects heart muscle cells from injury during hypoxia (a deficiency in the levels of oxygen in the blood). THC “delaying the onset of irreversible cell injury … on hypoxia-exposed cardiac cells in culture,” authors found. They concluded, “This research demonstrates that THC has beneficial effects on cardiac cells and supports the consideration of marijuana for specific medical uses.”