The effects of cannabidiol on the antigen-induced contraction of airways smooth muscle in the guinea-pig.

“(-)-Δ(9)-Tetrahydrocannabinol has been demonstrated to have beneficial effects in the airways, but its psychoactive effects preclude its therapeutic use for the treatment of airways diseases. In the present study we have investigated the effects of (-)-cannabidiol, a non-psychoactive component of cannabis for its actions on bronchial smooth muscle in vitro and in vivo.

 Guinea-pig bronchial smooth muscle contractions induced by exogenously applied spasmogens were measured isometrically. In addition, contractile responses of bronchial smooth muscle from ovalbumin-sensitized guinea-pigs were investigated in the absence or presence of (-)-cannabidiol. Furthermore, the effect of (-)-cannabidiol against ovalbumin-induced airway obstruction was investigated in vivo in ovalbumin-sensitized guinea pigs. (-)-Cannabidiol did not influence the bronchial smooth muscle contraction induced by carbachol, histamine or neurokinin A. In contrast, (-)-cannabidiol inhibited anandamide- and virodhamine-induced responses of isolated bronchi. A fatty acid amide hydrolase inhibitor, phenylmethanesulfonyl fluoride reversed the inhibitory effect of (-)-cannabidiol on anandamide-induced contractions. In addition, (-)-cannabidiol inhibited the contractile response of bronchi obtained from allergic guinea-pigs induced by ovalbumin. In vivo, (-)-cannabidiol reduced ovalbumin-induced airway obstruction.

 In conclusion, our results suggest that cannabidiol can influence antigen-induced airway smooth muscle tone suggesting that this molecule may have beneficial effects in the treatment of obstructive airway disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/23428645

[Cannabinoids for symptomatic therapy of multiple sclerosis].

“Spasticity represents a common troublesome symptom in patients with multiple sclerosis (MS). Treatment of spasticity remains difficult, which has prompted some patients to self-medicate with and perceive benefits from cannabis. Advances in the understanding of cannabinoid biology support these anecdotal observations.

Various clinical reports as well as randomized, double-blind, placebo-controlled studies have now demonstrated clinical efficacy of cannabinoids for the treatment of spasticity in MS patients. Sativex is a 1:1 mix of delta-9-tetrahydocannabinol and cannabidiol extracted from cloned Cannabis sativa chemovars, which recently received a label for treating MS-related spasticity in Germany.

The present article reviews the current understanding of cannabinoid biology and the value of cannabinoids as a symptomatic treatment option in MS.”

http://www.ncbi.nlm.nih.gov/pubmed/22080198

Sativex® in multiple sclerosis spasticity: a cost-effectiveness model.

“Multiple sclerosis (MS) is a chronic, progressive disease that carries a high socioeconomic burden. Spasticity (rigidity and spasms) is common in MS and a key contributor to MS-related disability.

This study evaluated the cost-effectiveness of Sativex®, a 9-d-tetrahydrocannabinol/cannabidiol-based oromucosal spray that acts as an endocannabinoid system modulator. Sativex was recently approved for the management of resistant MS spasticity as add-on medication.

CONCLUSION:

Despite having a relatively high acquisition cost, Sativex was shown to be a cost-effective treatment option for patients with MS-related spasticity.”

http://www.ncbi.nlm.nih.gov/pubmed/22681512

Endocannabinoid system modulator use in everyday clinical practice in the UK and Spain.

“Spasticity is a disabling complication of multiple sclerosis. Some commonly used oral medications include baclofen, tizanidine, anticonvulsants and benzodiazepines, but their benefits are modest.

Sativex(®) (GW Pharmaceuticals PLC, Porton Down, UK; Laboratorios Almirall, SA, Barcelona, Spain) is a unique cannabinoid-based medicine with two main active ingredients; 9-δ-tetrahydrocannabinol, which acts mainly on cannabinoid 1 receptors in the CNS and plays a key role in the modulation of spasticity and spasms, and cannabidiol, which has different properties, including minimization of the psychoactivity associated with 9-δ-tetrahydrocannabinol. Sativex is indicated for symptomatic improvement in adult patients with moderate-to-severe multiple sclerosis-related spasticity who have not responded adequately to other first- or second-line antispasticity medications, and who demonstrate clinically significant improvement in spasticity-related symptoms during an initial trial of therapy.

Over the past couple of years, Sativex has been approved for use in a number of European countries and ongoing postmarketing studies are evaluating the possible risks associated with Sativex treatment by systematically collecting all suspected adverse reactions that occur in patients from the start of treatment. Interim data from the UK as well as Spanish Sativex safety registries confirm that clinical benefit is maintained over the longer term despite the expected trend for deterioration owing to disease progression.

 Even after more than 2 years of use, no new safety/tolerability signals have emerged with Sativex, including no evidence of driving impairment and no relevant incidence of falls or other adverse events of concern, such as psychiatric or nervous system events.

Sativex appears to be a well-tolerated and useful add-on therapy in patients who have not achieved an adequate response with traditional antispastic agents.”

http://www.ncbi.nlm.nih.gov/pubmed/23369054

Cannabis and Δ(9)-tetrahydrocannabinol (THC) for weight loss?

“Obesity is one of the highest preventable causes of morbidity and mortality in the developed world. It has been well known for a long time that exposure to cannabis produces an increase of appetite (a phenomenon referred to as the ‘munchies’).

This phenomenon led to an exploration of the role of the endocannabinoid system in the regulation of obesity and associated metabolic syndrome. This effort subsequently led to the development of a successful therapeutic approach for obesity that consisted of blocking the cannabinoid CB(1) receptors using ligands such as Rimonabant in order to produce weight loss and improve metabolic profile. Despite being efficacious, Rimonabant was associated with increased rates of depression and anxiety and therefore removed from the market.

We recently discovered that the prevalence of obesity is paradoxically much lower in cannabis users as compared to non-users and that this difference is not accounted for by tobacco smoking status and is still present after adjusting for variables such as sex and age.

 Here, we propose that this effect is directly related to exposure to the Δ(9)-tetrahydrocannabinol (THC) present in cannabis smoke. We therefore propose the seemingly paradoxical hypothesis that THC or a THC/cannabidiol combination drug may produce weight loss and may be a useful therapeutic for the treatment of obesity and its complications.”

http://www.ncbi.nlm.nih.gov/pubmed/23410498

The pharmacologic and clinical effects of medical cannabis.

“Cannabis, or marijuana, has been used for medicinal purposes for many years. Several types of cannabinoid medicines are available in the United States and Canada. Dronabinol (schedule III), nabilone (schedule II), and nabiximols (not U.S. Food and Drug Administration approved) are cannabis-derived pharmaceuticals.

Medical cannabis or medical marijuana, a leafy plant cultivated for the production of its leaves and flowering tops, is a schedule I drug, but patients obtain it through cannabis dispensaries and statewide programs. The effect that cannabinoid compounds have on the cannabinoid receptors (CB(1) and CB(2) ) found in the brain can create varying pharmacologic responses based on formulation and patient characteristics. The cannabinoid Δ(9) -tetrahydrocannabinol has been determined to have the primary psychoactive effects; the effects of several other key cannabinoid compounds have yet to be fully elucidated. Dronabinol and nabilone are indicated for the treatment of nausea and vomiting associated with cancer chemotherapy and of anorexia associated with weight loss in patients with acquired immune deficiency syndrome. However, pain and muscle spasms are the most common reasons that medical cannabis is being recommended.

Studies of medical cannabis show significant improvement in various types of pain and muscle spasticity. Reported adverse effects are typically not serious, with the most common being dizziness. Safety concerns regarding cannabis include the increased risk of developing schizophrenia with adolescent use, impairments in memory and cognition, accidental pediatric ingestions, and lack of safety packaging for medical cannabis formulations. This article will describe the pharmacology of cannabis, effects of various dosage formulations, therapeutics benefits and risks of cannabis for pain and muscle spasm, and safety concerns of medical cannabis use.”

http://www.ncbi.nlm.nih.gov/pubmed/23386598

Update on the Role of Cannabinoid Receptors after Ischemic Stroke

“The endocannabinoid system is considered as a major modulator of the cerebral blood flow, neuroinflammation, and neuronal survival… Evidence from animal models and in vitro studies suggests a global protective role for cannabinoid receptors agonists in ischemic stroke…Given its potent anti-inflammatory activities on circulating leukocytes, the CB2 activation has been proven to produce protective effects against acute poststroke inflammation. In this paper, we will update evidence on different cannabinoid-triggered avenues to reduce inflammation and neuronal injury in acute ischemic stroke…

Synthetic cannabinoids have been also investigated in animal models showing an improvement of the ischemic injury in the liver, heart, and brain. Furthermore, phytocannabinoids have been also isolated from the Cannabis sativa. Since this plant contains about 80 different cannabinoids, a strong work is still needed to test all these active compounds. This delay in cannabinoid research might be also due to the very low dose of certain cannabinoids in the plant. Thus, since Δ9-tetrahydrocannabidiol (THC) and cannabidiol (CBD) represent up to 40% of the total cannabinoid mass, these compounds have been considered as the most active mediators…

The encouraging therapeutic results of this study are in partial contrast with previous case reports, suggesting a potential relationship between stroke and chronic cannabis abuse in young human beings…

We believe that the “cannabinoid” approach represents an interesting therapeutic strategy still requiring further validations to improve neurologic and inflammatory outcomes in ischemic stroke.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3337695/

Increased Severity of Stroke in CB1 Cannabinoid Receptor Knock-Out Mice

“These findings indicate that endogenous cannabinoid signaling pathways protect mice from ischemic stroke by a mechanism that involves CB1 receptors, and suggest that both blood vessels and neurons may be targets of this protective effect.

 Endogenous cannabinoid signaling pathways have been implicated in protection of the brain from hypoxia, ischemia, and trauma…

Cannabinoids, which include the marijuana constituent Δ9-tetrahydrocannabinol and endogenous cannabinoids (endocannabinoids) produced in the brain, exert many of their effects through the G-protein-coupled CB1 receptor.

Cannabinoids reduce neuronal death from a variety of insults, including excitotoxicity, oxidative stress, hypoxia, ischemic stroke and trauma…

Clinical stroke, which usually results from cerebral ischemia, is a common and frequently incapacitating problem for which satisfactory treatment is generally unavailable. Identifying new endogenous systems that mitigate ischemic brain injury through effects on neurons, blood vessels, or both (such as the endocannabinoid signaling pathway) may help to guide the search for improved therapies.”

Full text: http://www.jneurosci.org/content/22/22/9771.long

Dronabinol for supportive therapy in patients with malignant melanoma and liver metastases.

“Loss of appetite and nausea can reduce the quality of life of patients with malignant melanoma and liver metastases. Often established antiemetic drugs fail to bring relief. Tetrahydrocannabinol (THC, Marinol), which is the active agent of Indian hemp, has been used successfully in this situation for other malignant tumors.

PATIENTS AND METHODS:

We treated 7 patients with hematogenous metastatic melanoma and liver metastases suffering from extensive loss of appetite and nausea supportively with dronabinol (Marinol. All of these patients had previously received standard antiemetic therapy without adequate relief. Dronabinol is a synthetic Delta-tetrahydrocannabinol. The drug was administered in capsule form. We evaluated the palliative effects of dronabinol with a special patient evaluation form, which was filled out at the beginning of the therapy and again after 4 weeks.

RESULTS:

The majority of patients described a significant increase in appetite and decrease in nausea. These effects remained for some weeks, but then decreased as metastases progressed and the general condition worsened. All of the patients experienced slight to moderate dizziness, but it was not sufficiently troubling to cause interruption or termination of therapy.

CONCLUSION:

Loss of appetite and nausea due to liver metastases of malignant melanoma can be treated in individual cases supportively with Dronabinol.”

http://www.ncbi.nlm.nih.gov/pubmed/16408219

Cannabidiol Inhibits Growth and Induces Programmed Cell Death in Kaposi Sarcoma–Associated Herpesvirus-Infected Endothelium

“Kaposi sarcoma is the most common neoplasm caused by Kaposi sarcoma–associated herpesvirus (KSHV). Current treatments for Kaposi sarcoma can inhibit tumor growth but are not able to eliminate KSHV from the host. When the host’s immune system weakens, KSHV begins to replicate again, and active tumor growth ensues. New therapeutic approaches are needed.

Cannabidiol (CBD), a plant-derived cannabinoid, exhibits promising antitumor effects without inducing psychoactive side effects. CBD is emerging as a novel therapeutic for various disorders, including cancer.

In this study, we investigated the effects of CBD both on the infection of endothelial cells (ECs) by KSHV and on the growth and apoptosis of KSHV-infected ECs, an in vitro model for the transformation of normal endothelium to Kaposi sarcoma….

Cannabidiol (CBD) was first isolated in 1940. It is a major component of the plant Cannabis sativa, which is also the source of Δ9-tetrahydrocannabinol (Δ9-THC). Due to its multiple biological activities, CBD has been identified as a potential clinical agent. Moreover, CBD affects these activities without the psychoactive side effects that typify Δ9-THC. Recent studies have documented the potential antitumorigenic properties of CBD in the treatment of various neoplasms, including breast cancer, lung cancer, bladder cancer, glioblastoma,and leukemia.CBD induces these effects through a variety of mechanisms and signaling pathways

CBD has been evaluated clinically for the treatment of various conditions, including anxiety, psychosis, and pain. In contrast to other members of the cannabinoid family, CBD has a strong safety profile and induces no psychotropic effects.Therefore, it has become an attractive agent in the search for new anticancer therapies.Our current study demonstrated that CBD preferentially enhanced apoptosis and inhibited the proliferation of KSHV-infected endothelial cells. This selective targeting of KSHV-induced neoplasia suggests that CBD may have a desirable therapeutic index when used to treat cancer. Moreover, a recent study demonstrated that CBD can be delivered effectively by nasal and transdermal routes, which may be particularly valuable for the treatment of Kaposi sarcoma oral or skin lesions.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3527984/