New discoveries reported at the ICRS symposium highlight CBD's potential for treating anxiety, cancer, heart disease, substance use, brain injuries and more.

The 29th annual International Cannabinoid Research Society (ICRS) symposium, held the previous month in Bethesda, Maryland, presented new CBD science developments with broad implications across medicine.

More than 500 participants from around the world attended the four-day conference, featuring 65 oral presentations across a wide range of topics.

Harvard scientist Staci Gruber shared encouraging results from an initial open-label clinical trial evaluating a high-CBD, low-THC sublingual tincture in patients with moderate anxiety. None had used cannabinoid-based products before the study.

Gruber said preliminary data showed significant improvement from baseline after four weeks. Specifically, findings suggested a specially formulated, whole-plant-derived, high-CBD sublingual tincture was associated with less severe anxiety and fewer related symptoms.

After completing this open-label trial, Gruber planned a double-blind, placebo-controlled trial to produce empirically robust data on sublingual CBD's effectiveness for anxiety.

CBD for hypertension

Human subjects were recruited for a CBD study at the University of Nottingham, where Saoirse E. O'Sullivan and colleagues examined cannabidiol's acute and chronic cardiovascular effects.

Twenty-six healthy men received 600 mg oral CBD or placebo for seven days in a randomized, placebo-controlled, double-blind, parallel study. Results were mixed. Resting blood pressure measurements suggested tolerance developed with chronic administration, but CBD's blood-pressure-lowering ability persisted during stress.

O'Sullivan said reduced arterial stiffness and improvements in internal carotid artery blood flow and endothelial function after chronic treatment suggested a positive vascular effect warranting further research in relevant patient populations.

ICRS 2019 included several clinical-trial talks, but most CBD presentations concerned the latest preclinical data. Their striking depth and breadth emphasized CBD's versatile therapeutic potential.

CBD for stroke

A meta-analysis by Nottingham scientists examined CBD in animal models of focal ischemic stroke. It found CBD limited damage from induced brain injury, significantly reducing infarct volume and improving early functional outcomes in rodents with experimental stroke. Nottingham researchers also conducted applied preclinical research into the anti-inflammatory and neuroprotective effects of cannabidiolic acid (CBDA), the raw, unheated form of CBD in the plant. They concluded that CBDA, like CBD, reduced blood–brain barrier permeability and inflammation in a cellular stroke model. A compromised barrier is a key factor in the secondary injury cascade damaging the brain. CBD and CBDA restore barrier integrity by activating the 5-HT1a serotonin receptor, which mediates their anti-inflammatory effects. In Spain, neonatal animal experiments paved the way for clinical CBD testing in infants with brain injuries.

CBD for substance dependence

At publication, no FDA-approved medicine treated cocaine dependence. National Institute on Drug Abuse (NIDA) researchers therefore evaluated CBD's potential against cocaine. They administered CBD to cocaine-dependent rats and observed a downward shift in the cocaine self-administration dose-response curve with systemic treatment. They said these findings suggested potential therapeutic benefits in blunting cocaine's rewarding effects. They also identified molecular pathways involved in CBD's anti-addiction effects in laboratory animals, including the 5-HT1a serotonin receptor, CB2 cannabinoid receptor and the TRPV1 ion channel receptor. Chemical antagonists blocking these receptors' signaling negated the effects.

CBD for prostate cancer

Italian scientists studied two plant cannabinoids, CBD and cannabigerol (CBG), together against aggressive prostate cancer. Earlier work showed a 1:1 combination significantly reduced tumor recurrence in animals with hormone-refractory disease, inhibited cell proliferation and induced apoptosis in vitro. Their latest ICRS findings described how purified CBD and CBG affected malignant tumors' metabolic systems, producing marked shifts in specific cancer-related signaling pathways in prostate cancer cells.

According to the Italian researchers, this demonstrated phytocannabinoids' effectiveness as metabolic reprogramming agents, potentially laying foundations for a breakthrough treatment for highly malignant, hormone-refractory prostate cancer. Auburn University scientists reached similar conclusions about CBD and THC's antitumor properties, finding dose-dependent inhibition of prostate cell proliferation. This was encouraging for the one in nine men expected to develop prostate cancer, described as the second-leading cancer cause among American men. Auburn's preclinical experiment suggested cannabinoids could be developed as new therapeutic agents for prostate cancer.

CBD for arthritis and gum disease

Israeli, British and American scientists analyzed synthetic CBD's anti-inflammatory and pain-relieving effects in an animal arthritis model. The preclinical work found a strong analgesic effect and shed new light on CBD's anti-inflammatory mechanisms.

A preclinical investigation at the University of Leeds School of Dentistry documented CBD's anti-inflammatory effects on gum disease. It concluded CBD's ability to regulate immune function might offer therapeutic applications in periodontal research.