Nabilone. A preliminary review of its pharmacological properties and therapeutic use.

Abstract

“Nabilone is a new orally active cannabinoid for the treatment of severe gastrointestinal toxicity associated with cancer chemotherapy. The pharmacological profile of nabilone suggests that it acts primarily by preventing emesis controlled by the medulla oblongata, although its secondary mild anxiolytic activity may contribute to the overall efficacy. Nabilone 2mg twice daily starting 12 hours prior to, and continued for the duration of, chemotherapy produces significant reduction in the severity and duration of nausea and the frequency of vomiting in about 50 to 70% of patients with severe symptoms refractory to conventional therapy. Nabilone has proven to be more effective in controlling symptoms and preferred by more patients than prochlorperazine 10mg 2 to 4 times daily in a limited number of studies, despite a higher incidence of side effects. Comparative trials against other new antiemetic agents, such as high dose metoclopramide, and use of nabilone in combination with other antiemetics remain to be undertaken. The incidence of side effects is high with nabilone; drowsiness, dizziness and/or vertigo occur in 60 to 70% of patients, but rarely lead to drug withdrawal, although more troublesome effects, such as postural hypotension, ataxia, vision disturbance and toxic psychoses, may cause discontinuation of therapy. Thus, nabilone offers an effective alternative to the treatment options available in a difficult therapeutic area – those patients with severe gastrointestinal side effects from cancer chemotherapy who are refractory to conventional therapy.”

http://www.ncbi.nlm.nih.gov/pubmed/2863127

Anti-emetic efficacy and toxicity of nabilone, a synthetic cannabinoid, in lung cancer chemotherapy.

Abstract

“Nabilone, a synthetic cannabinoid, and Prochlorperazine were compared in a double-blind crossover study of 34 patients with lung cancer undergoing a 3-day schedule of chemotherapy with Cyclophosphamide, Adriamycin and Etoposide. Symptom scores were significantly better for patients on nabilone for nausea, retching and vomiting (P less than 0.05). Fewer subjects vomited with nabilone (P = 0.05) and the number of vomiting episodes was lower (P less than 0.05); no patients on nabilone required additional parenteral anti-emetic. More patients preferred nabilone for anti-emetic control (P less than 0.005). Adverse effects common with nabilone were drowsiness (57%), postural dizziness (35%) and lightheadedness (18%). Euphoria was seen in 14% and a “high” in 7%. Erect systolic blood pressure was lower in nabilone patients on Day 1 (P = 0.05) but postural hypotension was a major problem in only 7%. Nabilone is an effective oral anti-emetic drug for moderately toxic chemotherapy, but the range and unpredictability of its side-effects warrant caution in its use.”

http://www.ncbi.nlm.nih.gov/pubmed/6315040

Cannabidiolic acid prevents vomiting in Suncus murinus and nausea-induced behaviour in rats by enhancing 5-HT(1A) receptor activation.

“BACKGROUND AND PURPOSE:

To evaluate the ability of cannabidiolic acid (CBDA) to reduce nausea and vomiting and enhance 5-HT(1A) receptor activation in animal models.”

“CONCLUSIONS AND IMPLICATIONS:

Compared to cannabidiol, CBDA displays significantly greater potency at inhibiting vomiting in shrews and nausea in rats, and at enhancing 5-HT(1A) receptor activation, an action that accounts for its ability to attenuate conditioned gaping in rats. Consequently, CBDA shows promise as a treatment for nausea and vomiting, including anticipatory nausea for which no specific therapy is currently available.”

http://www.ncbi.nlm.nih.gov/pubmed/23121618

Cannabidiol, a non-psychotropic component of cannabis, attenuates vomiting and nausea-like behaviour via indirect agonism of 5-HT(1A) somatodendritic autoreceptors in the dorsal raphe nucleus.

Abstract

“BACKGROUND AND PURPOSE:

To evaluate the hypothesis that activation of somatodendritic 5-HT(1A) autoreceptors in the dorsal raphe nucleus (DRN) produces the anti-emetic/anti-nausea effects of cannabidiol (CBD), a primary non-psychoactive cannabinoid found in cannabis.”

“CONCLUSIONS AND IMPLICATIONS:

These results suggest that CBD produced its anti-emetic/anti-nausea effects by indirect activation of the somatodendritic 5-HT(1A) autoreceptors in the DRN.”

http://www.ncbi.nlm.nih.gov/pubmed/21827451

Anticonvulsant action of cannabis in the rat: role of brain monoamines.

Abstract

“The role of brain monoamines in the anticonvulsant action of Cannabis indica resin (CI), against maximal electroshock-induced seizures in albino rats, was investigated by using pharmacologic agents that influence brain monoamine activity. Delta-9-tetrahydrocannabinol content of cannabis resin was estimated to be 17%. The anticonvulsant action of CI (200 mg/kg, i.p.) was significantly inhibited after pretreatment with drugs that reduce brain serotonin activity but not by drugs that reduce brain catecholamine activity. Similarly, the anticonvulsant action of a subanticonvulsant dose (50 mg/kg, i.p.) of CI was potentiated by serotonin precursors but not by catecholamine precursors. Potentiation of the anticonvulsant action of CI by nialamide or by imipramine was inhibited after pretreatment with 5,6-dihydroxytryptamine. The results suggest that the anticonvulsant action of CI in the rat is serotonin- and not catecholamine-mediated.”

http://www.ncbi.nlm.nih.gov/pubmed/104333

Convulsions associated with the use of a synthetic cannabinoid product.

Abstract

“INTRODUCTION:

Clinical presentations following the use of various “spice” or synthetic cannabinoids have included agitation, anxiety, emesis, hallucinations, psychosis, tachycardia, and unresponsiveness. Convulsions were described in a one report although there was not laboratory confirmation for synthetic cannabinoids. In another published report laboratory confirmation for a synthetic cannabinoid was done in which the patient manifested activity that was interpreted as a possible convulsion.

CASE REPORT:

We describe a patient who had two witnessed generalized convulsions soon after smoking a “spice” product that we later confirmed to have four different synthetic cannabinoids.

DISCUSSION:

Convulsions have only rarely been associated with marijuana exposures. Recreational use of synthetic cannabinoids is a very recent phenomenon and there is a very limited, albeit burgeoning, literature detailing the associated complications including convulsions we have reported here. The absence of anticonvulsant phytocannabinoids in spice products could potentially be one of multiple unknown mechanisms contributing to convulsions.”

http://www.ncbi.nlm.nih.gov/pubmed/22160733

Suppression of human monocyte interleukin-1beta production by ajulemic acid, a nonpsychoactive cannabinoid.

Abstract

   “Oral administration of ajulemic acid (AjA), a cannabinoid acid devoid of psychoactivity, reduces joint tissue damage in rats with adjuvant arthritis. Because interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNFalpha) are central to the progression of inflammation and joint tissue injury in patients with rheumatoid arthritis, we investigated human monocyte IL-1beta and TNFalpha responses after the addition of AjA to cells in vitro… Reduction of IL-1beta by AjA may help explain the therapeutic effects of AjA in the animal model of arthritis. Development of nonpsychoactive therapeutically useful synthetic analogs of Cannabis constituents, such as AjA, may help resolve the ongoing debate about the use of marijuana as medicine.”

http://www.ncbi.nlm.nih.gov/pubmed/12566094

Ajulemic acid, a synthetic cannabinoid acid, induces an antiinflammatory profile of eicosanoids in human synovial cells.

“AIMS:

To better understand mechanisms whereby Ajulemic acid (AjA), a synthetic antiinflammatory cannabinoid, promotes resolution of acute and chronic inflammation in animal models, we investigated its influence on cyclooxygenase 2 (COX2) expression and eicosanoid production in human fibroblast-like synovial cells (FLS).”

“KEY FINDINGS:

AjA increased the steady state levels of COX2 mRNA in and arachidonic acid release from FLS. Treatment of FLS with AjA increased 15-deoxy-delta(12,14)-PGJ(2) (15d-PGJ(2)) production in a concentration dependent manner, but did not affect PGE(2) production significantly.”

“SIGNIFICANCE:

The capacity of AjA to increase selectively and markedly 15d-PGJ(2), an eicosanoid which facilitates resolution of inflammation, suggests that AjA may have value as a therapeutic agent for the treatment of rheumatoid arthritis (RA) and other diseases characterized by acute and chronic inflammation.”

http://www.ncbi.nlm.nih.gov/pubmed/18840450

Suppression of fibroblast metalloproteinases by ajulemic acid, a nonpsychoactive cannabinoid acid.

Abstract

   “Production of matrix metalloproteinases (MMP) in joint tissue of patients with inflammatory arthritis facilitates cartilage degradation and bone erosion, and leads to joint deformities and crippling. Thus, MMPs are important targets for agents designed to treat inflammatory arthritis. Oral administration of ajulemic acid (AjA), a synthetic, nonpsychoactive cannabinoid acid, prevents joint tissue injury in rats with adjuvant arthritis. AjA binds to and activates PPARgamma directly. Therefore, we investigated the influence of AjA on MMP production in human fibroblast-like synovial cells (FLS), and examined the role of PPARgamma in the mechanism of action of AjA. FLS, treated or not with a PPARgamma antagonist, were treated with AjA then stimulated with TNFalpha or IL-1alpha. Release of MMPs-1, 3, and 9 was measured by ELISA. The influence of AjA on MMP-3 release from stimulated PPARgamma positive (PPAR+/-) and PPARgamma null (PPAR-/-) mouse embryonic fibroblasts (MEF) was also examined. Addition of AjA to FLS suppressed production of MMPs whether or not PPARgamma activation was blocked. Secretion of MMP-3 was also suppressed by AjA in both TNFalpha- and IL-1alpha-stimulated PPARgamma+/- and PPARgamma-/- MEF. Suppression of MMP secretion from FLS by AjA appears to be PPARgamma independent. Prevention by AjA of joint tissue injury and crippling in the rat adjuvant arthritis model may be explained in large part by inhibition of MMPs. These results suggest that AjA may be useful for treatment of patients with rheumatoid arthritis and osteoarthritis.”

http://www.ncbi.nlm.nih.gov/pubmed/16927387

Cannabimimetic Properties of Ajulemic Acid

   “Side effects of marijuana-based drugs and synthetic analogs of Δ9-tetrahydrocannabinol (Δ9-THC), including sedation and dysphoria, have limited their therapeutic application. Ajulemic acid (AJA), a side-chain synthetic analog of Δ8-THC-11-oic acid, has been reported to have anti-inflammatory properties without producing undesired psychoactive effects. Moreover, it has been suggested that AJA does not interact with cannabinoid receptors to produce its pharmacological effects. The aim of the present study was to conduct a thorough evaluation of the pharmacological effects of AJA then to determine whether actions at cannabinoid receptor (CB)1 mediated these effects… These studies demonstrated that AJA shares a number of CB1-mediated pharmacological properties with Δ9-THC, including cannabimimetic, discriminative stimulus, and antihyperalgesic effects. Furthermore, a separation between doses that produced antinociception and those that produced the other pharmacological effects in mice was not observed. Moreover, AJA showed nearly equipotency for therapeutic efficacy in the CFA model and for substitution in Δ9-THC discrimination. In summary, this study shows that AJA, like Δ9-THC, exhibits psychoactive and therapeutic effects at nearly equal doses in preclinical models, suggesting similar limitations in their putative therapeutic profiles.”

“Cannabis sativa (marijuana plant) has been used since antiquity for its presumed therapeutic, as well as for its euphoric effects. Although Δ9-tetrahydrocannabinol (Δ9-THC) has been identified as the major psychoactive ingredient in C. sativa, difficulty in dissociating unwanted side effects, such as sedation and psychotropic effects, from therapeutic effects has limited clinical application of Δ9-THC-based drugs. For example, dronabinol, an orally administered synthetic version of Δ9-THC, has been developed as an appetite stimulant and antiemetic for use in chronic diseases such as AIDS and cancer. In addition, recent evidence suggests oral Δ9-THC may be effective as an adjunct to opioid analgesics. The therapeutic utility of Δ9-THC, however, has been limited due to patient complaints of dysphoria and unpleasant subjective effects. Previous research has suggested that Δ9-THC carboxylic acid, one of the acid metabolites of Δ9-THC, lacks psychoactive properties of the parent compound and yet retains antinociceptive and other effects. Since this metabolite has a relatively low potency, structural changes that increased potency and stability of Δ9-THC analogs in previous structure-activity relationship studies were applied to the structure Δ9-THC carboxylic acid. The resulting compound, ajulemic acid (AJA), substitutes a 1′,1-dimethylheptyl side chain for the pentyl group of Δ9-THC and changes the Δ9-THC core structure to a more stable confirmation, Δ8-THC (Fig. 1).”

Fig. 1

 
“To date, the efficacy of AJA has been demonstrated in numerous pain and inflammation studies…”
 
“These findings also underscore the importance of thoroughly evaluating the pharmacological characteristics of novel Δ9-THC-like compounds…”