Monoacylglycerol lipase (MGL) is a serine hydrolase that plays a major role in the degradation of endogenous cannabinoid 2-arachidonoylglycerol. The role of MGL in some cancer cells has been confirmed, where inhibition of the MGL activity shows inhibition on cell proliferation. This makes MGL a promising drug target for the treatment of cancer. Recently, the development of covalent inhibitors of MGL has developed rapidly. These drugs have strong covalent binding ability, high affinity, long duration, low dose and low risk of drug resistance, so they have received increasing attention. This article introduces the structure and function of MGL, the characteristics, mechanisms and progress of covalent MGL inhibitors, providing reference for the development of novel covalent small molecule inhibitors of MGL.
Monoacylglycerol Lipases/metabolism* ; Endocannabinoids/metabolism*

Globally, it is evident that glioblastoma multiforme (GBM) is an aggressive malignant cancer with a high mortality rate and no effective treatment options. Glioblastoma is classified as the stage-four progression of a glioma tumor, and its diagnosis results in a shortened life expectancy. Treatment options for GBM include chemotherapy, immunotherapy, surgical intervention, and conventional pharmacotherapy; however, at best, they extend the patient's life by a maximum of 5 years. GBMs are considered incurable due to their high recurrence rate, despite various aggressive therapeutic approaches which can have many serious adverse effects. Ceramides, classified as endocannabinoids, offer a promising novel therapeutic approach for GBM. Endocannabinoids may enhance the apoptosis of GBM cells but have no effect on normal healthy neural cells. Cannabinoids promote atypical protein kinase C, deactivate fatty acid amide hydrolase enzymes, and activate transient receptor potential vanilloid 1 (TRPV1) and TRPV2 to induce pro-apoptotic signaling pathways without increasing endogenous cannabinoids. In previous in vivo studies, endocannabinoids, chemically classified as amide formations of oleic and palmitic acids, have been shown to increase the pro-apoptotic activity of human cancer cells and inhibit cell migration and angiogenesis. This review focuses on the biological synthesis and pharmacology of endogenous cannabinoids for the enhancement of cancer cell apoptosis, which have potential as a novel therapy for GBM. Please cite this article as: Duzan A, Reinken D, McGomery TL, Ferencz N, Plummer JM, Basti MM. Endocannabinoids are potential inhibitors of glioblastoma multiforme proliferation. J Integr Med. 2023; 21(2): 120-128.
Humans ; Glioblastoma/pathology* ; Endocannabinoids/therapeutic use* ; Brain Neoplasms/pathology* ; Cell Proliferation ; Cell Line, Tumor ; Cannabinoids/therapeutic use*

With the recent legalization of recreational cannabis in Canada and 11 states of the U.S., the interest surrounding cannabis use is increasing. However, many people and even clinicians in Korea do not have exact knowledge about the psychiatric consequences of cannabis use. In this narrative review, the characteristics of cannabis, the endocannabinoid system, and the psychiatric consequences of cannabis use were provided. Cannabis contains more than 80 cannabinoids in the native plant. Psychotropic properties of Δ-9-tetrahydrocannabinol and cannabidiol are most well studied. The two main receptors are cannabinoid-1 receptor and cannabinoid-2 receptor. Several endocannabinoids, such as anandamide and 2-arachidonoylglycerol, act on the receptors as the endogenous ligands. Cannabis influences mood, cognitive functions, and psychomotor functions in acute phase responses, increasing the odds ratio for motor vehicle crashes. Long-term cannabis use is associated with various psychotic outcomes, including the development of schizophrenia, although there is interindividual variability. Cannabis adversely influences learning, memory, and attention. More frequent, persistent, and earlier onset cannabis use is associated with greater cognitive impairment. The chronic cognitive effects of cannabis are complex and controversial. Cannabis has addictive potential, and cannabis use disorder is common. Clinicians should have evidence-based knowledge about the consequences of cannabis use and communicate accurate information about cannabis use and its associated risks to the public.
Canada ; Cannabidiol ; Cannabinoids ; Cannabis ; Cognition ; Cognition Disorders ; Endocannabinoids ; Korea ; Learning ; Ligands ; Marijuana Abuse ; Memory ; Motor Vehicles ; Odds Ratio ; Plants ; Psychoses, Substance-Induced ; Schizophrenia

Endocannabinoids and cannabinoid receptors are expressed in various central pain modulation regions. They maintain in dynamic changes in the expression level and distribution under different pathological and physiological conditions. These changes possess advantage as well as disadvantage. Exogenous administration of endocannabinoids exerts analgesic effect in different pain models, which is mainly mediated by the cannabinoid CB1 and CB2 receptors. Inhibition of enzymes for degrading endocannabinoids in different pain models also shows analgesic effect due to the increased local levels of endocannabinoids.
Endocannabinoids ; Humans ; Neuralgia ; Receptor, Cannabinoid, CB1 ; Receptor, Cannabinoid, CB2

Endocannabinoids can affect multiple cellular targets, such as cannabinoid (CB) receptors, transient receptor potential cation channel, subfamily V, member 1 (TRPV1) and peroxisome proliferator-activated receptor gamma (PPARgamma). The stimuli to induce adipocyte differentiation in hBM-MSCs increase the gene transcription of the CB1 receptor, TRPV1 and PPARgamma. In this study, the effects of three endocannabinoids, N-arachidonoyl ethanolamine (AEA), N-arachidonoyl dopamine (NADA) and 2-arachidonoyl glycerol (2-AG), on adipogenesis in hBM-MSCs were evaluated. The adipocyte differentiation was promoted by AEA whereas inhibited by NADA. No change was observed by the treatment of non-cytotoxic concentrations of 2-AG. The difference between AEA and NADA in the regulation of adipogenesis is associated with their effects on PPARgamma transactivation. AEA can directly activate PPARgamma. The effect of AEA on PPARgamma in hBM-MSCs may prevail over that on the CB1 receptor mediated signal transduction, giving rise to the AEA-induced promotion of adipogenesis. In contrast, NADA had no effect on the PPARgamma activity in the PPARgamma transactivation assay. The inhibitory effect of NADA on adipogenesis in hBM-MSCs was reversed not by capsazepine, a TRPV1 antagonist, but by rimonabant, a CB1 antagonist/inverse agonist. Rimonabant by itself promoted adipogenesis in hBM-MSCs, which may be interpreted as the result of the inverse agonism of the CB1 receptor. This result suggests that the constantly active CB1 receptor may contribute to suppress the adipocyte differentiation of hBM-MSCs. Therefore, the selective CB1 agonists that are unable to affect cellular PPARgamma activity inhibit adipogenesis in hBM-MSCs.
Adipocytes* ; Adipogenesis ; Dopamine* ; Endocannabinoids ; Ethanolamine ; Felodipine ; Glycerol ; Humans ; Mesenchymal Stromal Cells* ; PPAR gamma ; Receptor, Cannabinoid, CB1 ; Receptors, Cannabinoid* ; Signal Transduction ; Transcriptional Activation

OBJECTIVETo investigate the mechanism of N- Arachidonoylethanolamine (ANA) on inhibiting platelets (PLT) apoptosis under standard blood bank storage conditions.

METHODSSamples taken from collected apheresis PLT by the Amicus instrument were split into three parts. An aliquot of 0.5 μmol/L ANA were added to one part of storage PLT as the ANA group; an aliquot of 0.5 μmol/L ANA and 1 μmol/L SR141716 was added to the another part as the ANA + SR141716 group; and the third part without ANA and SR141716 as the control group. These samples were stored on a flat-bed shaker at (22 ± 2) ⁰C for 7 days. The expression of phosphatidyl serine (PS) positive, phospho (p)-Akt, Akt, p-Bad, Bad, caspase-3, caspase-9, cytochrome C (Cyt-C) and BCL-XL interaction with Bak were detected.

RESULTSThe rate of PLT PS positive in ANA group decreased significantly than that in control group[ (8.29 ± 1.44) % vs (14.24 ± 2.47) %, P<0.05]. The release of Cyt-C from mitochondria to cytosol in ANA group decreased significantly compared with control group[ (3.29 ± 1.44) % vs (15.24 ± 3.40) %, P<0.05]. Also the expressions of p-Akt and p-Bad in ANA group increased significantly than those in control group[ (71.33 ± 10.26) % vs (35.00 ± 6.00) %, P<0.05; (39.00 ± 9.64) % vs (10.33 ± 1.53) %, P<0.05, respectively]. Higher amounts of Bak protein were co-precipitated with BCL-XL in ANA group than that in control group (about 2.6 fold, P<0.05). The expressions of cleaved caspase- 9 and caspase- 3 in ANA group decreased significantly than those in control group[ (9.63 ± 1.47) % vs (23.24 ± 2.47) %, P<0.05; (6.30 ± 1.40) % vs (13.20 ± 2.50) %, P<0.05, respectively]. There were no significantly changes between ANA+SR141716 and control groups (P>0.05).

CONCLUSIONANA protected PLTs from apoptosis as a result of inhibiting the release of Cyt-C from mitochondria to cytosol by modifying the expressions of apoptosis-relative proteins.

Apoptosis ; drug effects ; Blood Platelets ; cytology ; drug effects ; Caspase 3 ; Caspase 9 ; Cytochromes c ; Endocannabinoids ; pharmacology ; Humans ; Mitochondria ; Proto-Oncogene Proteins c-akt

To observe a PPAR-alpha agonist effect of N-oleoylethanolamine (OEA) on CB2 (cannabinoid receptor 2), an anti-inflammatory receptor in vascular endothelial cell, healthy HUVECs and TNF-alpha induced HUVECs were used to establish a human vascular endothelial cell inflammatory model. Different doses of OEA (10, 50 and 100 micromol x L(-1)) had been given to HUVECs, cultured at 37 degrees C for 7 h and then collected the total protein and total mRNA. CB2 protein expression was detected by Western blotting and CB2 mRNA expression was assayed by real-time PCR. As the results shown, OEA (10 and 50 micromol x L(-1)) could induce the CB2 protein and mRNA expression, but not 100 micromol x L(-1). To detect if anti-inflammation effect of OEA is partly through CB2, CB2 inhibitor AM630 was used to inhibit HUVEC CB2 expression, then the VCAM-1 expression induced by TNF-alpha was detected, or THP-1 adhere to TNF-alpha induced HUVECs was examined. OEA (50 micromol x L(-1)) could inhibit TNF-alpha induced VCAM-1 expression and THP-1 adhere to HUVECs, these effects could be partly inhibited by a CB2 inhibitor AM630. The anti-inflammation effect of OEA is induced by PPAR-alpha and CB2, suggesting that CB2 signaling could be a target for anti-atherosclerosis, OEA have wide effect in anti-inflammation, it may have better therapeutic potential in anti-inflammation in HUVECs, thus achieving anti-atherosclerosis effect.
Anti-Inflammatory Agents ; pharmacology ; Atherosclerosis ; pathology ; Cell Adhesion ; drug effects ; Cells, Cultured ; Endocannabinoids ; pharmacology ; Endothelial Cells ; cytology ; metabolism ; Ethanolamines ; pharmacology ; Humans ; Indoles ; pharmacology ; Monocytes ; drug effects ; Oleic Acids ; pharmacology ; PPAR alpha ; antagonists & inhibitors ; RNA, Messenger ; metabolism ; Receptor, Cannabinoid, CB2 ; antagonists & inhibitors ; genetics ; metabolism ; Tumor Necrosis Factor-alpha ; pharmacology ; Vascular Cell Adhesion Molecule-1 ; metabolism

This study was purposed to investigate the effects of N-Arachidonoylethanolamine (ANA) on the quality of platelets (Plt) stored in Plt M-sol preservative solution at 22 ± 2°C. Samples taken from collecting apheresis Plt by the Amicus instrument and splited into two equal parts were stored in Plt M-sol preservative solution on a shaker at 22 ± 2°C. Different working concentrations of ANA (from 0.1 to 50 µmol/L) were then added into one part of stored Plt as the experimental group, the other without ANA was used as the control group. The viability of Plts stored at 22 ± 2°C for 7 days was evaluated by MTT colorimetric assay. The most effective concentration of ANA was selected and added to the subsequent experimental group. Plt count (BPC), mean Plt volume (MPV), Plt distribution width (PDW), phosphatidyl serine (PS) and soluble P-selectin were detected on the 1(st), 5(th), 7(th), 9(th) and 11(th) day of storage. The results showed that the most effective working concentration of ANA was 0.5 µmol/L, which showed significant increasing Plt viability (91.23 ± 5.44%) compared to the control group (62.54 ± 4.79%). Thus, ANA concentration at 0.5 µmol/L was choose to perform subsequent experiments. During 11 days of storage, the BPC, MPV and PDW were not changed significantly between the experimental group and control group, although there was decreasing trend in the BPC and increasing trends in MPV and PDW in the two groups. The rate of Plt PS positive was enhanced during the storage period: the rate of PS positive in experimental group increased from 7.69 ± 1.82% to 10.74 ± 1.78% while it in control group increased from 11.21 ± 2.03% to 15.37 ± 1.95%, with significant differences between the two groups (P < 0.05) on the 9(th) and 11(th) day of storage, respectively. Soluble P-selectin contents in experimental group on the 9(th) and 11(th) day of storage were 30.19 ± 2.03 ng/ml and 34.52 ± 2.64 ng/mL, respectively, while those in control group were 39.18 ± 2.66 ng/ml and 43.23 ± 2.58 ng/ml, respectively, with significant differences between the two groups (P < 0.05). It is concluded that the extended storage of Plt in M-sol treated with low concentration ANA can potentially alleviate Plt storage lesions.
Adult ; Blood Platelets ; drug effects ; Blood Preservation ; Endocannabinoids ; pharmacology ; Female ; Humans ; Male

The plant Cannabis has been used in clinic for centuries, and has been known to be beneficial in a variety of gastrointestinal diseases, such as emesis, diarrhea, inflammatory bowel disease and intestinal pain. In this text, we'll review the components of the endogenous cannabinoid system as well as its role in the regulation of gastrointestinal activities, thus providing relative information for further study. Moreover, modulation of the endogenous cannabinoid system in gastrointestinal tract may provide a useful therapeutic target for gastrointestinal disorders.
Animals ; Cannabinoid Receptor Modulators ; pharmacology ; Endocannabinoids ; physiology ; Gastrointestinal Diseases ; physiopathology ; Gastrointestinal Tract ; physiology ; Humans

Endocannabinoid anandamide (AEA) has protective effect on the heart against ischemia/reperfusion injury and arrhythmia, but the electrophysiological mechanism is unclear yet. In this study, the sinoatrial node (SAN) samples from New Zealand rabbits were prepared, and intracellular recording technique was used to elucidate the effect of AEA on the action potential (AP) of SAN pacemaker cells of rabbits and the mechanism. Different concentrations of AEA (1, 10, 100, 200, 500 nmol/L) were applied cumulatively. For some SAN samples, cannabinoid type 1 (CB1) receptor antagonist AM251, cannabinoid type 2 (CB2) receptor antagonist AM630, potassium channel blocker tetraethylammonium (TEA) and nitric oxide (NO) synthase inhibitor L-nitro-arginine methylester (L-NAME) were used before AEA treatment, respectively. We found that: (1) AEA (100, 200 and 500 nmol/L) not only shortened AP duration (APD), but also decreased AP amplitude (APA) (P < 0.05). (2) AM251, but not AM630, abolished the effect of AEA on APD shortening. (3) TEA and L-NAME had no influence on the AEA effect. These findings suggest that anandamide can decrease APA and shorten APD in SAN pacemaker cells of rabbits, which may be mediated by activation of CB1 receptors, and is related to blockade of calcium channels but not potassium channels and NO.
Action Potentials ; Animals ; Arachidonic Acids ; pharmacology ; Cannabinoid Receptor Antagonists ; pharmacology ; Endocannabinoids ; pharmacology ; Indoles ; pharmacology ; Myocytes, Cardiac ; drug effects ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitric Oxide ; metabolism ; Piperidines ; pharmacology ; Polyunsaturated Alkamides ; pharmacology ; Potassium Channel Blockers ; pharmacology ; Pyrazoles ; pharmacology ; Rabbits ; Sinoatrial Node ; cytology