IACM-Bulletin of February 26, 2012

Science — The levels of endocannabinoids are increased by high intake of an omega-6 fatty acid and cause obesity in animals

Linoleic acid, which is found in relatively high amounts in soybean, sunflower and corn oil, increased levels of endocannabinoids in mice and caused obesity according to research by scientists from the University of Bergen, Norway, and the National Institutes of Health in Bethesda, USA. Researchers investigated the effects of a 14-week diet high in linoleic acid, an omega-6 fatty acid. They hypothesized that this fatty acid, a precursor of arachidonic acid, from which endocannabinoids are formed, would induce endocannabinoid hyperactivity. Intake of linoleic acid was increased from 1 per cent to 8 per cent of calories of the diet, intended to reflect the increase of omega-6 fatty acids in the food of US Americans during the 20th century. This was mainly due to a dramatic increase in the consumption of soybean oil used for the production of margarines, vegetable oil, fast food, baked goods and other processed foods.

Increasing linoleic acid to 8 per cent elevated phospholipids of arachidonic acid in liver and red blood cells and tripled the concentration of the endocannabinoids 2-AG (2-arachidonoyl glycerol) and anandamide (AEA) in the animals. This was associated with increased food intake and obesity. Reducing phospholipids of arachidonic acid by adding 1 per cent long-chain omega-3 fatty acids to 8 per cent linoleic acid resulted in metabolic patterns resembling 1 per cent linoleic acid diets. They wrote: "In summary, dietary LA [linoleic acid] increased tissue AA [arachidonic acid], and subsequently elevated 2-AG+1-AG and AEA resulting in the development of diet-induced obesity." They stated that the obesity causing effect of linoleic acid could be prevented by a sufficient intake of omega-3 fatty acids, which reduces the concentration of arachidonic acid and normalises the endocannabinoid tone.

(Source: Alvheim AR, Malde MK, Osei-Hyiaman D, Hong Lin Y, Pawlosky R, Madsen L, Kristiansen K, Frøyland L, Hibbeln JR. Dietary linoleic acid elevates endogenous 2-AG and anandamide and induces obesity. Obesity (Silver Spring). 2012 Feb 15. [in press])

News in brief

Science — Beta-caryophyllene prevents from kidney damage by cisplatin

According to scientists of the National Institutes of Health in Bethesda, USA, beta-caryophyllene reduces toxicity to the kidneys induced by the chemotherapeutic agent cisplatin in mice. Beta-caryophyllene is a terpene found in the essential oils of many plants including cannabis, black pepper, oregano and rosemary. It binds to the CB2 receptor. Authors concluded that beta-caryophyllene (BCP) "may be an excellent therapeutic agent to prevent cisplatin-induced nephrotoxicity through a CB2 receptor-dependent pathway. Given the excellent safety profile of BCP in humans it has tremendous therapeutic potential in a multitude of diseases associated with inflammation and oxidative stress." (Source: Horváth B, et al. Free Radic Biol Med. 2012 Jan 31. [in press])

Science USA — Cities profit from taxes on medicinal cannabis

According to an article in the New York Times several cities raise significant revenues from tax payments by medical cannabis dispensaries. Oakland raised 1.4 million US Dollars (about 1.0 million Euros) last year, Colorado Springs 0.7 million USD (about 0.5 million Euros) and Denver 3.4 million USD (about 2.5 million Euros). Oregon raised 6.7 million USD (about 5.0 million Euros) from yearly fees for the participation in the state's medical cannabis program. (Source: New York Times of 12 February 2012)

USA — Cannabis increases traffic accidents by the factor 2

According to a review published in the British Medical Journal even acute cannabis use increases the risk for traffic accidents only by the factor 2, far below the risk caused by alcohol. Driving under the influence of cannabis was associated with a significantly increased risk of motor vehicle collisions compared with unimpaired driving (odds ratio 1.9). Collision risk estimates were higher in case-control studies (2.8) and studies of fatal collisions (2.1) than in culpability studies (1.65) and studies of non-fatal collisions (1.7). (Source: Asbridge M, t al. BMJ. 2012 Feb 9;344:e536.)

Science — Local administration of cannabinoids against pain

Researchers of a university in Madrid, Spain, investigated the efficacy of local administration of cannabinoids (CB1 and CB2 receptor agonists) in muscle pain of animals. They wrote: "Our results provide evidence that both, CB1 and CB2 receptors can contribute to muscular antinociception." (Source: Sánchez Robles EM, et al. Eur J Pain. 2012 Feb 21. [in press])

Science — Cannabinoids ameliorate disease progression in MS

According to Spanish researchers the use of a synthetic cannabinoid (WIN55,212-2) in a mouse model of multiple sclerosis reduced the neurological disability of animals and the progression of the disease. Scientists found out that "this effect was exerted through the activation of CB1 receptors, which would exert a positive influence in the reduction of inflammatory events linked to the pathogenesis of this disease." (Source: de Lago E, et al. Neuropharmacology. 2012 Feb 8. [in press])

Science — Plant estrogens increase the effect of anandamide on blood vessels in females

According to research at the University of Buenos Aires, Argentina, plant estrogens such as genistein and daidzein potentiated the anandamide-induced reduction of contractility of blood vessels in female but not in male rats. These estrogens are flavonoids present in many plants, including soybeans, coffee, and fava beans. (Source: Peroni RN, et al. Int J Hypertens 2012;2012:647856.)