anandamide and Metabolic-Syndrome

2-Arachidonoyl-glycerol (2-AG) and arachidonyl-ethanolamide (AEA) are endocannabinoids that have been implicated in many physiologic disorders, including obesity, metabolic syndromes, hepatic diseases, pain, neurologic disorders, and inflammation. Their immunomodulatory effects are numerous and are not always mediated by cannabinoid receptors, reflecting the presence of an arachidonic acid (AA) molecule in their structure, the latter being the precursor of numerous bioactive lipids that are pro- or anti-inflammatory. 2-AG and AEA can thus serve as a source of AA but can also be metabolized by most eicosanoid biosynthetic enzymes, yielding additional lipids. In this regard, enhancing endocannabinoid levels by using endocannabinoid hydrolysis inhibitors is likely to augment the levels of these lipids that could regulate inflammatory cell functions. This review summarizes the metabolic pathways involved in the biosynthesis and metabolism of AEA and 2-AG, as well as the biologic effects of the 2-AG and AEA lipidomes in the regulation of inflammation.

Topics: Animals; Arachidonic Acids; Dendritic Cells; Endocannabinoids; Glycerides; Humans; Inflammation; Lipid Metabolism; Liver Diseases; Lymphocytes; Metabolic Syndrome; Neurodegenerative Diseases; Obesity; Pain; Phosphatidic Acids; Polyunsaturated Alkamides; Receptors, Cannabinoid

Development of the metabolic syndrome results from the interaction of genetic and environmental factors. Metabolic syndrome together with smoking represents risk factors for the development of cardiovascular complications. They may result from the hyperstimulation of the endocannabinoid system. The CB1 receptor has been assumed to play an important role in the endocannabionoid system. It is abundantly expressed in the brain, and in other parts of human body such as in the fat tissue. Rimonabant is a selective blocker of cannabinoid-1 (CB1) receptors and participates in the regulation of impaired endocannabinoid system. In the overweight humans, it stimulates sustained reduction of the body weight, girth size and it improves lipid and glucose metabolism. Rimonabant also reduces nicotine self-administration and may be effective not only as an aid for smoking cessation but also in the prevention of body weight increase related to the smoking cessation as it was documented in Rio-Lipids and Stratus-us studies.

Topics: Arachidonic Acids; Cannabinoid Receptor Antagonists; Cannabinoid Receptor Modulators; Endocannabinoids; Humans; Metabolic Syndrome; Piperidines; Polyunsaturated Alkamides; Pyrazoles; Rimonabant; Smoking; Smoking Cessation; Weight Loss

Vaccenic acid (VA), the predominant ruminant-derivedtransfat in the food chain, ameliorates hyperlipidemia, yet mechanisms remain elusive. We investigated whether VA could influence tissue endocannabinoids (ECs) by altering the availability of their biosynthetic precursor, arachidonic acid (AA), in membrane phospholipids (PLs). JCR:LA-cprats were assigned to a control diet with or without VA (1% w/w),cis-9,trans-11 conjugated linoleic acid (CLA) (1% w/w) or VA+CLA (1% + 0.5% w/w) for 8 weeks. VA reduced the EC, 2-arachidonoylglycerol (2-AG), in the liver and visceral adipose tissue (VAT) relative to control diet (P< 0.001), but did not change AA in tissue PLs. There was no additive effect of combining VA+CLA on 2-AG relative to VA alone (P> 0.05). Interestingly, VA increased jejunal concentrations of anandamide and those of the noncannabinoid signaling molecules, oleoylethanolamide and palmitoylethanolamide, relative to control diet (P< 0.05). This was consistent with a lower jejunal protein abundance (but not activity) of their degrading enzyme, fatty acid amide hydrolase, as well as the mRNA expression of TNFα and interleukin 1β (P< 0.05). The ability of VA to reduce 2-AG in the liver and VAT provides a potential mechanistic explanation to alleviate ectopic lipid accumulation. The opposing regulation of ECs and other noncannabinoid lipid signaling molecules by VA suggests an activation of benefit via the EC system in the intestine.

Topics: Amidohydrolases; Animals; Anti-Inflammatory Agents; Arachidonic Acids; Caco-2 Cells; Cytokines; Dietary Supplements; Disease Models, Animal; Endocannabinoids; Ethanolamines; Gene Expression Regulation, Enzymologic; Humans; Inflammation; Intestinal Mucosa; Intestines; Intra-Abdominal Fat; Liver; Male; Membrane Lipids; Metabolic Syndrome; Oleic Acids; Polyunsaturated Alkamides; Rats; RNA, Messenger

Blood pressure responses to intrathecal (i.t.) injection of neurochemicals were examined in the fructose-fed rat, an experimental model of metabolic syndrome.Sprague-Dawley rats receiving either tap water or water containing 10% fructose during 8 weeks were anesthetized with sodium pentobarbital. The endocannabinoid anandamide (100 nmol; i.t.) decreased mean blood pressure in control rats (-21.2 ± 6.3 mm Hg), but had no effect in fructose-fed animals. Similarly, calcitonin gene-related peptide (CGRP; 0.125 nmol; i.t.) decreased mean blood pressure in control, but not in treated rats. The high fructose diet did not cause significant changes in the pressor effects of i.t. administered noradrenaline (100 nmol) and N-methyl-d-aspartate (30 nmol). The nitric oxide donor sodium nitroprusside (500 nmol, i.t.) induced a brief hypotension followed by a sustained increase in mean blood pressure in control rats; however, this drug only produced pressor effects in fructose-fed animals. The GABAA-receptor agonist muscimol (8.8 nmol, i.t.) and the GABAB-receptor agonist baclofen (100 nmol, i.t.) decreased mean blood pressure 30-35 mm Hg, both in control and in fructose-fed rats. Fructose potentiated the pressor effect of i.v. injected noradrenaline, but did not modify the hypotensive responses to i.v. administered sodium nitroprusside and acetylcholine.These results could suggest that, in pentobarbital-anesthetized rats, fructose feeding could alter spinal mechanisms of regulation of preganglionic sympathetic nerve activity. It is proposed that the spinal cord could be involved in the sympathetic dysfunction associated with the metabolic syndrome.

Topics: Animals; Arachidonic Acids; Baclofen; Blood Glucose; Blood Pressure; Calcitonin Gene-Related Peptide; Cholesterol; Diet; Endocannabinoids; Fructose; Heart Rate; Injections, Spinal; Lipid Peroxidation; Male; Metabolic Syndrome; Muscimol; N-Methylaspartate; Nitroprusside; Norepinephrine; Polyunsaturated Alkamides; Rats; Rats, Sprague-Dawley; Spinal Cord; Thiobarbituric Acid Reactive Substances; Triglycerides