AM630 is an inverse agonist at the human cannabinoid CB1 receptor

doi:10.1016/S0024-3205(97)01187-9

Life Sciences

Volume 62, Issue 9, 23 January 1998, Pages PL109-PL113

https://doi.org/10.1016/S0024-3205(97)01187-9 Get rights and content

Abstract

The present investigation examines WIN 55,212-2 and AM630 at the cloned human cannabinoid CB₁ receptor stably expressed in Chinese hamster ovary (CHO) cells. The effect of various concentrations of WIN 55,212-2 and AM630 on basal [³⁵S]GTPγS binding to cell membranes was determined. WIN 55,212-2 (100 μM) stimulated basal [³⁵S]GTPγS binding 77.9% with an EC₅₀ value of 0.36 μM. Conversely, AM630 (100 μM) inhibited basal [³⁵S]GTPγS binding by 20.9% with an EC₅₀ value of 0.90 μM. These results show that WIN 55,212-2 is an agonist and AM630 is an inverse agonist in this system.

References (12)

R.G. Pertwee et al.
Life Sci.
(1995)
O.H. Lowry et al.
J. Biol. Chem.
(1951)
J.D. Richardson et al.
Eur. J. Pharmacol.
(1997)
M. Bouaboula et al.
J. Biol. Chem.
(1997)
R.S. Landsman et al.
Eur. J. Pharmacol.
(1997)
R.G. Pertwee et al.
J. Pharmacol.
(1996)

There are more references available in the full text version of this article.

Cited by (53)

N-linoleyltyrosine exerts neuroprotective effects in APP/PS1 transgenic mice via cannabinoid receptor-mediated autophagy
2021, Journal of Pharmacological Sciences
Citation Excerpt :
Therefore, the effect of CB2 receptor-AM630 on the activities of NITyr was determined to confirm the potential mechanism. Although most studies reported that AM630 was an antagonist of CB2 receptor, a small amount of studies showed that AM630 also behaved as a weak partial agonist at CB1 receptors or an invers agonist at the human cannabinoid CB1 receptor.46,47 The possible explanation for this discrepancy in AM630 action would be a species difference, cannabinoid receptor types or the role of the tissue in determining drug action.
Anandamide (AEA) analogs show fair effects in counteracting the deterioration of Alzheimer's disease (AD). Our previous studies demonstrated that AEA analog-N-linoleyltyrosine (NITyr) exerted significant activities. In our current research, the role and mechanisms of NITyr were assessed in APP/PS1 mice mimicking the AD model. NITyr improved motor coordination in the rotarod test (RRT) and ameliorated spatial memory in the Morris water maze (MWM) but did not increase spontaneous locomotor activity in the open field test (OFT). In addition, NITyr protected neurons against β-amyloid (Aβ) injury via hematoxylin-eosin (HE) and Nissl staining. Moreover, the related biochemical indexes showed that NITyr reduced the levels of Aβ₄₀ and Aβ₄₂ in the hippocampus but did not affect the expression of p-APP and β-secretase 1 (BACE1). Furthermore, the autophagy inhibitor 3-methyladenine (3 MA) attenuated the effect of NITyr on animal behaviors and neurons. Meanwhile, NITyr upregulated the expression levels of LC3-II and Beclin-1, which were weakened by AM630 (an antagonist of CB₂ receptor and a weak partial agonist of CB₁ receptors). AM630 also weakened the role of NITyr in animal behaviors. Thus, NITyr improved behavioral impairment and neural loss by inducing autophagy mainly mediated by the CB₂ receptor, and weakly mediated by the CB₁ receptor.
Medicinal Chemistry approach, pharmacology and neuroprotective benefits of CB<inf>2</inf>R modulators in neurodegenerative diseases
2021, Pharmacological Research
Citation Excerpt :
AM-630, [6-iodo-2-methyl-1-[2-(4-morpholinyl)ethyl]-1H-indol-3-yl](4-methoxyphenyl)methanone] (Fig. 12), was originally described as a CBRs antagonist in the mouse isolated vas deferens, as reported by Pertwee et al. [138], but it also possessed the properties of a weak cannabinoid CB1R agonist in the myenteric plexus-longitudinal muscle preparation of guinea-pig small intestine [139]. Furthermore, two reports classified AM-630 as a CBRs antagonist in mouse and guinea-pig brain membrane preparations [140] and as an inverse agonist in chinese hamster ovary (CHO) cells stably transfected with CB1R [141]. However, the research group of Ross et al. found AM-630 to behave also as an inverse agonist at CB2R in CB2R-transfected cells, showing to be CB2R-selective with a CB1/CB2 Ki ratio of 165 in transfected CHO cell membranes [142].
In the last decades, cannabinoid receptor 2 (CB₂R) has continued to receive attention as a key therapeutic target in neuroprotection. Indeed, several findings highlight the neuroprotective effects of CB₂R through suppression of both neuronal excitability and reactive microglia. Additionally, CB₂R seems to be a more promising target than cannabinoid receptor 1 (CB₁R) thanks to the lack of central side effects, its lower expression levels in the central nervous system (CNS), and its inducibility, since its expression enhances quickly in the brain following pathological conditions. This review aims to provide a thorough overview of the main natural and synthetic selective CB₂R modulators, their chemical classification and their potential therapeutic usefulness in neuroprotection, a crucial aspect for the treatment of neurodegenerative diseases.
Influence of the CB<inf>1</inf> and CB<inf>2</inf> cannabinoid receptor ligands on the activity of atypical antidepressant drugs in the behavioural tests in mice
2020, Pharmacology Biochemistry and Behavior
Citation Excerpt :
Therefore, we assume that the enhancement of the serotoninergic neurotransmission may be particularly responsible for the observed interactions between CB receptor ligands and agomelatine, whereas potentiation of the dopaminergic signaling may be mainly responsible for the positive interplay between CB receptor ligands and tianeptine. Keeping in mind that AM630 is not only an inverse agonist/antagonist of CB2 receptors but it also has an affinity towards CB1 receptors and it acts as their inverse agonist (Landsman et al., 1998), one can suspect that an interplay between AM630 and CB1 receptors can contribute to the final effects of AM630 treatment in our studies. We guess that co-administration of oleamide and agomelatine as well as concurrent use of JWH133 and agomelatine or tianeptine were unable to sufficiently increase the levels of monoamines, and this is the reason why these combinations did not induce shortening of the immobility time of animals in the applied behavioural tests.
Available data support the notion that cannabinoids, whose therapeutic value is limited due to severe adverse reactions, could be beneficial as adjunctive agents in the management of mood disorders. Polytherapy, which is superior to monotherapy in the terms of effectiveness, usually requires lower doses of the individual components. Therefore, the main objective of our study was to determine whether administration of cannabinoid (CB) receptor ligands would enhance the antidepressant activity of atypical antidepressant drugs, i.e. agomelatine and tianeptine. To evaluate the antidepressant-like potential of the tested combinations, the mouse forced swim test (FST) and the tail suspension test (TST) were used. The HPLC method was applied to assess the brain levels of agomelatine and tianeptine. Both behavioural tests demonstrated that per se an ineffective intraperitoneal dose of oleamide (CB₁ receptor agonist, 5 mg/kg) potentiated the anti-immobility activity of tianeptine (15 mg/kg), whereas AM251 (CB₁ receptor inverse agonist/antagonist, 0.25 mg/kg) enhanced the antidepressant effects of tianeptine and agomelatine (20 mg/kg). Intraperitoneal co-administration of per se inactive doses of AM630 (CB₂ receptor inverse agonist/antagonist) and agomelatine or tianeptine significantly reduced the immobility time of animals only in the FST. CB receptor ligands did not affect the brain levels of the tested atypical antidepressants. In summary, the outcomes of the present study showed that activation and inhibition of CB₁ receptors as well as inhibition of CB₂ receptors may increase the antidepressant activity of tianeptine, whereas only inhibition of CB₁ and CB₂ receptors has a potential to augment the antidepressant activity of agomelatine.
A structure-function approach identifies L-PGDS as a mediator responsible for glucocorticoid-induced leptin expression in adipocytes
2019, Biochemical Pharmacology
Citation Excerpt :
However, when we applied in vitro COX enzymatic activity assays treated with 1 or 10 μM AM630, we found no change to either COX-1 or COX-2 activity (Fig. 2A). AM630 has also been shown to be a weak agonist or inverse agonist of CB1 [24,25]. We therefore treated differentiated primary preadipocytes with a panel of CB ligands (Fig. 2B), including WIN55212-2 (CB1/CB2 dual agonist), ACEA (CB1 selective agonist), HU210 (CB1/CB2 dual agonist) and rimonabant (CB1 inverse agonist) [13], and measured leptin expression.
Leptin is an adipokine predominantly secreted by adipocytes and has many physiological roles, including in energy homeostasis. We identified that AM630, a cannabinoid receptor 2 (CB2) antagonist, down-regulated leptin expression in mature adipocytes differentiated from either stromal vascular fractions isolated from inguinal fat pads of C57BL/6J mice or 3T3-L1 preadipocytes. However, the leptin-suppressive effects of AM630 preserved in CB2-deficient adipocytes indicated the off-target activity of AM630 in leptin expression. Pharmacological and genetic studies, cheminformatics, and docking simulation were applied to identify the potential protein target of AM630 that modulates leptin expression in differentiated primary preadipocytes. Screening of the reported off-targets of AM630 identified a synthetic cannabinoid WIN55212-2 exerting the same function. Target deconvolution and docking simulation suggested that AM630 and WIN55212-2 were both inhibitors of lipocalin-type prostaglandin D2 synthase (L-PGDS). Further studies showed that L-PGDS positively regulates leptin expression. Although glucocorticoid and aldosterone were previously reported to induce expression of both L-PGDS and leptin, our data demonstrated that L-PGDS mediates only glucocorticoid-induced leptin expression in differentiated primary preadipocytes. No effect was observed after aldosterone treatment. This newly discovered glucocorticoid – L-PGDS – leptin pathway may provide insights into current clinical use of glucocorticoid and management of their undesired effects such as obesity.
The endocannabinoid system: Overview of an emerging multi-faceted therapeutic target
2019, Prostaglandins Leukotrienes and Essential Fatty Acids
Citation Excerpt :
For example, AM 630 has been reported to reverse CP 55,940-induced inhibition of forskolin-stimulated cyclic AMP production by human CB2R-transfected CHO cell preparations at concentrations in the nanomolar range (EC50 = 129 nM) and to enhance forskolin-stimulated cyclic AMP production by the same cell line when administered by itself (EC50 = 230 nM) [70], albeit with an efficacy that appears to be somewhat less than the inverse efficacy displayed by SR144528 in this bioassay [72]. At the CB1R, AM 630 has been found to behave in some investigations as a low potency partial agonist [70,73] but in others as a low potency inverse agonist [74,75]. Endocannabinoids are crucial to bioregulation.
The endocannabinoids anandamide (AEA) and 2-arachidonoylglyerol (2-AG) are endogenous lipid mediators that exert protective roles in pathophysiological conditions, including cardiovascular diseases. In this brief review, we provide a conceptual framework linking endocannabinoid signaling to the control of the cellular and molecular hallmarks, and categorize the key components of endocannabinoid signaling that may serve as targets for novel therapeutics. The emerging picture not only reinforces endocannabinoids as potent regulators of cellular metabolism but also reveals that endocannabinoid signaling is mechanistically more complex and diverse than originally thought.
Antinociceptive effect of cannabinoid agonist WIN 55,212-2 in rats with a spinal cord injury
2007, Experimental Neurology
Spinal cord injury (SCI) pain exhibits many symptoms associated with peripheral neuropathic pain, including increased tactile hypersensitivity. One novel approach to ameliorate SCI pain is the use of cannabinoid (CB) ligands. The current study evaluated the efficacy of the nonselective CB receptor agonist WIN 55,212-2 on tactile hypersensitivity in rats following a brief compression to the thoracic spinal cord. The withdrawal thresholds of the hind paws following SCI were significantly decreased, indicating tactile hypersensitivity. Systemic injection of WIN 55,212-2 increased withdrawal thresholds in a dose-dependent manner. Pretreatment with the CB₁ receptor subtype-selective antagonist AM 251 completely abolished the antinociceptive effect of WIN 55,212-2 whereas pretreatment with the CB₂ receptor subtype-selective antagonist AM 630 did not alter the antinociceptive effect of WIN 55,212-2. These data indicate that a CB₁-selective agonist may be novel therapeutic treatment for clinical SCI pain.

View all citing articles on Scopus

View full text

Pharmacology letter Accelerated communicationAM630 is an inverse agonist at the human cannabinoid CB1 receptor

Abstract

Life Sci.

J. Biol. Chem.

Eur. J. Pharmacol.

J. Biol. Chem.

Eur. J. Pharmacol.

J. Pharmacol.

Pharmacology letter Accelerated communication
AM630 is an inverse agonist at the human cannabinoid CB₁ receptor