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Sumner Burstein

Publications and source records attributed to Sumner Burstein.

6 recordsLinked to original sources

PPAR-gamma: a nuclear receptor with affinity for cannabinoids.

An increasing number of cannabinoid actions are being reported that do not appear to be mediated by either CB1 or CB2, the known cannabinoid receptors. One such example is the synthetic analog ajulemic acid (AJA), which shows potent analgesic and anti-inflammatory effects in rodents and humans. AJA binds weakly to CB1 only at concentrations many fold higher than its therapeutic range, and is, therefore, completely free of psychotropic effects in both normal subjects and pain patients suggesting the involvement of a target site other than CB1. AJA as well as several other cannabinoids appear to have profound effects on cellular lipid metabolism as evidenced by their ability to transform fibroblasts into adipocytes where the accumulation of lipid droplets can be readily observed. Such transformations can be mediated by the activation of the nuclear receptor PPAR-gamma. A variety of small molecule ligands including AJA have been shown to induce the activation of PPAR-gamma and, in some cases this has led to the introduction of clinically useful agents. It is suggested that PPAR-gamma may serve a receptor function for certain actions of some cannabinoids.

Azo Compounds↗

Pain measurements and side effect profile of the novel cannabinoid ajulemic acid.

Preclinical findings on ajulemic acid (AJA) showed analgesic and anti-allodynic effects without psychoactive properties making it an appealing substance for the treatment of pain. A recently published randomized double-blind crossover clinical trial described the pain-reducing effects and side effect profile of AJA on 21 patients with chronic neuropathic pain. In this report from this same sample the effects of AJA on the mechanical hypersensitivity, on pain, and on psychological and physical performance were further characterized. During a 5-week study period, patients were divided into two 7-day treatment groups receiving either AJA or placebo capsules first, respectively. All patients received 40 and 80 mg of AJA or placebo daily in each treatment period. Pain measurements included the determination of mechanical hypersensitivity using the von Frey hair method as well as the visual analog scale (VAS), for which the number needed to treat (NNT) was calculated. The side effect profile of the compound was evaluated using psychotropic and physical measurements as well as obtaining reports on possible subjective side effects. The results showed no significant reduction in mechanical hypersensitivity (p=0.052), although a tendency towards pain reduction could be seen. The VAS score showed significant pain reduction (p=0.021) and NNT values for 30% pain relief were 2.14 for the first treatment group and 5.29 for the second treatment group. No significant findings were observed regarding psychotropic or physical measurements. Reported subjective side effects were mainly dry mouth, tiredness and dizziness and did not increase with dose elevation. Overall, these study findings indicate that AJA shows pain-reducing effects on patients with chronic neuropathic pain without clinically relevant psychotropic or physical side effects.

Adult↗

A structure-activity relationship study on N-arachidonoyl-amino acids as possible endogenous inhibitors of fatty acid amide hydrolase.

N-arachidonoyl-glycine (NAGly) has been recently identified in rodent tissues and found to exhibit analgesic activity in vivo. NAGly is a potent inhibitor of the fatty acid amide hydrolase (FAAH), the enzyme primarily responsible for the degradation of the endocannabinoid N-arachidonoyl-ethanolamine (anandamide), and was shown recently to elevate the blood levels of the this analgesic compound. We have synthesized several N-arachidonoyl-amino acids of potential natural occurrence, as well as the D- and L-isomers of N-arachidonoyl-alanine, and have tested their activity on FAAH preparations from mouse, rat, and human cell lines, and from mouse or rat brain. The results indicate that the relative potency and enantioselectivity of N-arachidonoyl-amino acids as FAAH inhibitors depend on the animal species. Thus, whilst NAGly is the most potent compound on the rat and mouse enzymes, N-arachidonoyl-isoleucine is active only on human FAAH and N-arachidonoyl-alanine enantiomers show a varying degree of potency. Taken together, these data support the view that an enhancement of endogenous anandamide levels underlies in part the analgesic effects of NAGly in rodents.

Alanine↗

Analgesic effect of the synthetic cannabinoid CT-3 on chronic neuropathic pain: a randomized controlled trial.

CONTEXT: 1',1'dimethylheptyl-Delta8-tetrahydrocannabinol-11-oic acid (CT-3), a potent analog of THC-11-oic acid, produces marked antiallodynic and analgesic effects in animals without evoking the typical effects described in models of cannabinoids. Therefore, CT-3 may be an effective analgesic for poorly controlled resistant neuropathic pain. OBJECTIVE: To examine the analgesic efficacy and safety of CT-3 in chronic neuropathic pain in humans. DESIGN AND SETTING: Randomized, placebo-controlled, double-blind crossover trial conducted in Germany from May-September 2002. PARTICIPANTS: Twenty-one patients (8 women and 13 men) aged 29 to 65 years (mean, 51 years) who had a clinical presentation and examination consistent with chronic neuropathic pain (for at least 6 months) with hyperalgesia (n = 21) and allodynia (n = 7). INTERVENTIONS: Patients were randomized to two 7-day treatment orders in a crossover design. Two daily doses of CT-3 (four 10-mg capsules per day) or identical placebo capsules were given during the first 4 days and 8 capsules per day were given in 2 daily doses in the following 3 days. After a washout and baseline period of 1 week each, patients crossed over to the second 7-day treatment period. MAIN OUTCOME MEASURES: Visual analog scale (VAS) and verbal rating scale scores for pain; vital sign, hematologic and blood chemistry, and electrocardiogram measurements; scores on the Trail-Making Test and the Addiction Research Center Inventory-Marijuana scale; and adverse effects. RESULTS: The mean differences over time for the VAS values in the CT-3-placebo sequence measured 3 hours after intake of study drug differed significantly from those in the placebo-CT-3 sequence (mean [SD], -11.54 [14.16] vs 9.86 [21.43]; P =.02). Eight hours after intake of the drug, the pain scale differences between groups were less marked. No dose response was observed. Adverse effects, mainly transient dry mouth and tiredness, were reported significantly more often during CT-3 treatment (mean [SD] difference, -0.67 [0.50] for CT-3-placebo sequence vs 0.10 [0.74] for placebo-CT-3 sequence; P =.02). There were no significant differences with respect to vital signs, blood tests, electrocardiogram, Trail-Making Test, and Addiction Research Center Inventory-Marijuana scale. No carryover or period effects were observed except on the Trail-Making Test. CONCLUSIONS: In this preliminary study, CT-3 was effective in reducing chronic neuropathic pain compared with placebo. No major adverse effects were observed.

Adult↗

Ajulemic acid, a nonpsychoactive cannabinoid acid, induces apoptosis in human T lymphocytes.

Oral administration of ajulemic acid (AjA), a synthetic nonpsychoactive cannabinoid acid, prevents joint cartilage and bone damage in an experimental model of arthritis in rats. Joint tissue injury in patients with rheumatoid arthritis (RA) is due in part to activation of T lymphocytes in the synovium, and T lymphocytes in synovium of RA patients are resistant to apoptosis. Thus, a potential mechanism whereby AjA prevents joint tissue injury in the animal model might be enhanced apoptosis of T lymphocytes. Apoptosis of human T cells in vitro was assessed by Annexin V expression, caspase-3 activity, DNA fragmentation, and microscopy. AjA induced apoptosis of T cells in a dose- and time-dependent manner. Apoptosis preceded loss of cell viability by trypan blue dye exclusion, confirming that cell loss was due to programmed cell death rather than necrosis. A nontoxic compound such as AjA may be a useful therapeutic agent for patients with diseases such as RA which are characterized by T-cell-driven chronic inflammation and tissue injury.

Annexin A5↗