Inulin may prevent the high-fat diet induced-obesity via suppressing endocannabinoid system in the prefrontal cortex in Wistar rats.

High-fat diets contribute to various metabolic disorders. Inulin supplementation has been shown to reduce appetite, lower food intake, and promote weight loss. Although there is evidence that the endocannabinoid system has metabolic effects in the prefrontal cortex, studies investigating the effects of inulin on the endocannabinoid system are limited. This study investigated the impact of inulin on obesity through the endocannabinoid system in the prefrontal cortex. Twenty-four male Wistar rats were fed one of four diets over 12 weeks. Findings indicated that a high-fat diet led to obesity, whereas inulin reduced food intake and supported weight loss. Consequently, inulin supplementation both prevented obesity and significantly decreased the expressions of Adrb3 and Adcy1, and anandamide and 2-arachidonylglycerol levels in the prefrontal cortex. Additionally, inulin lowered leptin in circulation and stimulated Trpv1. Thus, inulin may mitigate obesity development, possibly by modulating gene expressions linked to obesity in the prefrontal cortex via endocannabinoids.

FAAH inhibitor URB597 shows anti-hyperalgesic action and increases brain and intestinal tissues fatty acid amides in a model of CRF1 agonist mediated visceral hypersensitivity in male rats.

BACKGROUND AND AIMS: The endocannabinoid (eCB) system includes ligands (anandamide and 2-arachidonoyl glycerol, 2-AG), receptors and catabolizing enzymes (fatty acid amide hydrolase, FAAH and monoacylglycerol lipase) expressed in both the brain and gut. We investigated whether the FAAH inhibitor, URB597, influenced visceral pain to colorectal distension (CRD) in an acute stress-related model of visceral hypersensitivity induced by the selective corticotropin-releasing factor receptor subtype 1 (CRF1) agonist, cortagine. METHODS: Male Sprague-Dawley rats were injected subcutaneously (SC) with URB597 (3 mg/kg) or vehicle and 2 h later, intraperitoneally with cortagine (10 µg/kg) or vehicle. The visceromotor responses (VMR) were assessed to a first CRD (baseline) before injections, and to a second CRD 15 min after the last treatment. Brain, jejunum, and proximal colon were collected from treated and naïve rats for levels quantification of three fatty acid amides (FAAs) [anandamide (arachidonyl-ethanolamide, AEA), oleoyl-ethanolamide (OEA) and palmitoyl-ethanolamide (PEA)], and 2-AG. In separate animals, defecation/diarrhea were monitored after URB597 and cortagine. KEY RESULTS: URB597 inhibited cortagine-induced increased VMR at 40 mmHg (89.0 ± 14.8% vs. 132.5 ± 15.6% for vehicle SC, p < 0.05) and 60 mmHg (107.5 ± 16.1% vs. 176.9 ± 24.4% for vehicle SC, p < 0.001) while not influencing basal VMR. In URB597 plus cortagine group, FAAs levels increased in the brain and intestinal tissue while 2-AG did not change. URB597 did not modify cortagine-induced defecation/diarrhea versus vehicle. CONCLUSIONS AND INFERENCES: URB597 shows efficacy to elevate brain and intestinal FAAs and to counteract the colonic hypersensitivity induced by peripheral activation of CRF1 signaling supporting a potential strategy of FAAH inhibitors to alleviate stress-related visceral hypersensitivity.

Effect of central administration of indomethacin on anandamide-induced GnRH/LH secretion in the hypothalamus of anoestrous ewes.

Introduction: It is suggested that cannabinoids (CBs) may disturb reproduction through action on hypothalamic gonadotropin-releasing hormone (GnRH) neurons directly or indirectly through intermediates such as prostaglandins. The study aimed to determine the influence of intracerebroventricular (i.c.v.) injection of the endogenous cannabinoid anandamide (N-arachidonoylethanolamine - AEA), alone or with the prostaglandin synthesis inhibitor indomethacin (IND), on GnRH/luteinising hormone (LH) secretion. The purpose of the research was to clarify the role of endocannabinoids and their interaction with prostaglandins in the regulation of reproduction at the level of the hypothalamus and pituitary in anoestrous sheep. Material and Methods: The study was performed on 24 anoestrous ewes divided into four experimental groups: a control group receiving i.c.v. injection of Ringer-Locke solution, an AEA group that received i.c.v. injection of 30 µM of AEA, an IND group receiving i.c.v. injection of 5 µM of IND and an AEA + IND group that received i.c.v. injections of 30 µM of AEA and 5 µM of IND. Results: Anandamide stimulated GnRH protein and gene expression in the median eminence and protein expression in the preoptic area without influencing GnRH messenger RNA (mRNA) in this structure. Indomethacin reversed the changes in GnRH secretion after AEA administration. It was also found that AEA stimulated LH mRNA in the pituitary without influencing LH release. Conclusion: Our results support the role of endogenous cannabinoids in the regulation of reproductive processes at the central nervous system level. They may act directly on the hypothalamic GnRH neurons or indirectly through intermediates such as prostaglandins.

Targeting dysfunctional endocannabinoid signaling in a mouse model of Gulf War illness.

Gulf War Illness (GWI) is a chronic disorder characterized by a heterogeneous set of symptoms that include pain, fatigue, anxiety, and cognitive impairment. These are thought to stem from damage caused by exposure under unpredictable stress to toxic Gulf War (GW) chemicals, which include pesticides, nerve agents, and prophylactic drugs. We hypothesized that GWI pathogenesis might be rooted in long-lasting disruption of the endocannabinoid (ECB) system, a signaling complex that serves important protective functions in the brain. Using a mouse model of GWI, we found that tissue levels of the ECB messenger, anandamide, were significantly reduced in the brain of diseased mice, compared to healthy controls. In addition, transcription of the Faah gene, which encodes for fatty acid amide hydrolase (FAAH), the enzyme that deactivates anandamide, was significant elevated in prefrontal cortex of GWI mice and brain microglia. Behavioral deficits exhibited by these animals, including heightened anxiety-like and depression-like behaviors, and defective extinction of fearful memories, were corrected by administration of the FAAH inhibitor, URB597, which normalized brain anandamide levels. Furthermore, GWI mice displayed unexpected changes in the microglial transcriptome, implying persistent dampening of homeostatic surveillance genes and abnormal expression of pro-inflammatory genes upon immune stimulation. Together, these results suggest that exposure to GW chemicals produce a deficit in brain ECB signaling which is associated with persistent alterations in microglial function. Pharmacological normalization of anandamide-mediated ECB signaling may offer an effective therapeutic strategy for ameliorating GWI symptomology.

Central cholinergic transmission modulates endocannabinoid-induced marble-burying behavior in mice.

Central cholinergic system and endocannabinoid, anandamide exhibits anti-compulsive-like behavior in mice. However, the role of the central cholinergic system in the anandamide-induced anti-compulsive-like behavior is still unexplored. Therefore, the present study assessed the role of central cholinergic transmission in the anandamide-induced anti-compulsive activity using a marble-burying behavior (MBB) model in mice. The modulation in the anandamide-induced effect on MBB was evaluated using mice with altered central cholinergic transmission achieved by pretreatment (i.c.v.) with various cholinergic agents like acetylcholine (ACh), acetylcholinesterase inhibitor (AChEI), neostigmine, nicotine, mAChR antagonist, atropine, and nAChR antagonist, mecamylamine. The influence of anandamide treatment on the brain AChE activity was also evaluated. The results revealed that i.c.v. injection of anandamide (10, 20 µg/mouse, i.c.v.) dose-dependently reduced MBB in mice. Moreover, anandamide in all the tested doses inhibited the brain AChE activity indicating the role of an enhanced central cholinergic transmission in its anti-compulsive-like effect . Furthermore, the anti-compulsive-like effect of anandamide (20 µg/mouse, i.c.v.) was found to be enhanced in mice centrally pre-treated with, ACh (0.1 µg/mouse, i.c.v.) or AChEI, neostigmine (0.3 µg/mouse, i.c.v.). In addition, the anandamide-induced anti-compulsive-like effect was significantly increased in mice pre-treated with a low dose of nicotine (0.1 µg/mouse, i.c.v.) while, it was attenuated by the higher dose of nicotine (2 µg/mouse, i.c.v.). On the other hand, the anandamide (20 µg/mouse, i.c.v.) induced anti-compulsive-like effect was found to be diminished in mice pre-treated with mAChR antagonist, atropine (0.1, 0.5 µg/mouse, i.c.v.) and pre-injection of nAChR antagonist, mecamylamine (0.1, 0.5 µg/mouse, i.c.v.) potentiated the anandamide induced anti-compulsive-like response in mice. Thus, the present investigation delineates the modulatory role of an enhanced central cholinergic transmission in the anandamide-induced anti-compulsive-like behavior in mice by inhibition of brain AChE or via muscarinic and nicotinic receptors mediated mechanism.

Characterization of a Fatty Acid Amide Hydrolase (FAAH) in Hirudo Verbana.

The endocannabinoid system plays a critical role in modulating both peripheral and central nervous system function. Despite being present throughout the animal kingdom, there has been relatively little investigation of the endocannabinoid system beyond traditional animal models. In this study, we report on the identification and characterization of a putative fatty acid amide hydrolase (FAAH) in the medicinal leech, Hirudo verbana. FAAH is the primary enzyme responsible for metabolizing the endocannabinoid signaling molecule arachidonoyl ethanolamide (anandamide or AEA) and therefore plays a critical role in regulating AEA levels in the nervous system. mRNA encoding Hirudo FAAH (HirFAAH) is expressed in the leech central nervous system (CNS) and sequence analysis suggests that this is an orthologue of FAAH-2 observed in vertebrates. Functionally, HirFAAH has serine hydrolase activity based on activity-based protein profiling (ABPP) studies using the fluorophosphonate probe TAMRA-FP. HirFAAH also hydrolyzes arachidonyl 7-amino, 4-methyl coumarin amide (AAMCA), a substrate specific to FAAH. Hydrolase activity during both the ABPP and AAMCA assays was eliminated by a mutation at a conserved catalytic serine. Activity was also blocked by the known FAAH inhibitor, URB597. Treatment of Hirudo ganglia with URB597 potentiated synapses made by the pressure-sensitive mechanosensory neuron (P cell), mimicking the effects of exogenously applied AEA. The Hirudo CNS has been a useful system in which to study properties of endocannabinoid modulation of nociception relevant to vertebrates. Therefore, this characterization of HirFAAH is an important contribution to comparative studies of the endocannabinoid system.

Mitigation of cisplatin-induced acute kidney injury through oral administration of FAAH Inhibitor PF-04457845.

Fatty acid amide hydrolase (FAAH) serves as the primary enzyme responsible for degrading the endocannabinoid anandamide (AEA). Inhibition of FAAH, either through pharmacological means or genetic manipulation, can effectively reduce inflammation in various organs, including the brain, colon, heart, and kidneys. Infusion of a FAAH inhibitor into the kidney medulla has been shown to induce diuretic and natriuretic effects. FAAH knockout mice have shown protection against both post-ischemia reperfusion injury and cisplatin-induced acute kidney injury (AKI), although through distinct mechanisms. The present study was based on the hypothesis that pharmacological inhibition of FAAH activity could mitigate cisplatin-induced AKI, exploring potential renoprotective mechanism. Male wild type C57BL/6 were administered an oral gavage of a FAAH inhibitor (PF-04457845, 5mg/kg) or vehicle (10% PEG200+5% Tween80+normal saline) at 72, 48, 24, and 2 hours before and 24 and 48 hours after a single intraperitoneal injection of cisplatin (Cis, 25 mg/kg). Mice were euthanatized 72 hours after cisplatin treatment. Compared to vehicle-treated mice, PF-04457845-treated mice showed a decrease of cisplatin-induced plasma creatinine, blood urea nitrogen levels, kidney injury biomarkers (NGAL and KIM-1) and renal tubular damage. The renal protection from oral gavage of PF-04457845 against cisplatin-induced nephrotoxicity was associated with an enhanced AEA tone and reduced levels of DNA damage response biomarkers p53 and p21. Our work demonstrates that PF-04457845 effectively alleviates cisplatin-induced nephrotoxicity in mice, underscoring the potential of orally targeting FAAH as a novel strategy to prevent cisplatin nephrotoxicity. Significance Statement Oral administration of FAAH inhibitor, can reduce cisplatin-induced DNA damage response, tubular damages, and kidney dysfunction. Inactivation of FAAH could be a potential strategy to prevent cisplatin-induced nephrotoxicity.

Advances in targeted liquid chromatography-tandem mass spectrometry methods for endocannabinoid and N-acylethanolamine quantification in biological matrices: A systematic review.

Liquid chromatography paired with tandem mass spectrometry (LC-MS/MS) is the gold standard in measurement of endocannabinoid concentrations in biomatrices. We conducted a systematic review of literature to identify advances in targeted LC-MS/MS methods in the period 2017-2024. We found that LC-MS/MS methods for endocannabinoid quantification are relatively consistent both across time and across biomatrices. Recent advances have primarily been in three areas: (1) sample preparation techniques, specific to the chosen biomatrix; (2) the range of biomatrices tested, recently favoring blood matrices; and (3) the breadth of endocannabinoid and endocannabinoid-like analytes incorporated into assays. This review provides a summary of the recent literature and a guide for researchers looking to establish the best methods for quantifying endocannabinoids in a range of biomatrices.

Anandamide modulation of monocyte-derived Langerhans cells: implications for immune homeostasis and skin inflammation.

Introduction: The endocannabinoid system (ECS), named after the chemical compounds found in the cannabis plant, is a regulatory network of neurotransmitters, receptors, and enzymes that plays crucial roles in skin health and disease. Endogenous ligands of the ECS, called endocannabinoids, have proven to be important regulators of immune responses. One of the most prevalent endocannabinoids, arachidonoylethanolamide (also known as anandamide), is known for its anti-inflammatory effects. Langerhans cells (LCs) are the sole antigen-presenting cells present in the human epidermis. They serve as the first line of defense against pathogens and are essential for the skin's specific immune responses and play a critical role in maintaining tissue homeostasis; however, little is known about the effect of endocannabinoids on these cells. Our research aimed to provide the connection between monocyte-derived Langerhans cells (moLCs) and the ECS, shedding light on their collaborative roles in immune homeostasis and inflammation. Methods: Human monocytes were differentiated into moLCs using established protocols. Anandamide was applied during the differentiation process to test its effect on the viability, marker expression, and cytokine production of the cells, as well as in short term treatments for intracellular calcium measurement. TLR ligands applied after the differentiation protocol were used to activate moLCs. The impact of anandamide on the functionality of moLCs was further assessed using differential gene expression analysis of bulk RNA-Seq data, moLC-T cell cocultures, while ELISpot was employed to determine polarization of T cells activated in the aforementioned cocultures. Results: Anandamide did not significantly affect the viability of moLCs up to 10 µM. When applied during the differentiation process it had only a negligible effect on CD207 expression, the prototypic marker of LCs; however, there was an observed reduction in CD1a expression by moLCs. Anandamide had no significant effects on the maturation status of moLCs, nor did it affect the maturation induced by TLR3 and TLR7/8 agonists. MoLCs differentiated in the presence of anandamide did however show decreased production of CXCL8, IL-6, IL-10 and IL-12 cytokines induced by TLR3 and TLR7/8 activation. Anandamide-treated moLCs showed an increased capability to activate naïve T cells; however, not to the level seen with combined TLR agonism. RNA sequencing analysis of moLCs differentiated with anandamide showed modest changes compared to control cells but did reveal an inhibitory effect on oxidative phosphorylation specifically in activated moLCs. Anandamide also promoted the polarization of naïve T cells towards a Th1 phenotype. Discussion: Our results show that anandamide has nuanced effects on the differentiation, maturation, cytokine secretion, metabolism and function of activated moLCs. Among these changes the decrease in CD1a expression on moLCs holds promise to selectively dampen inflammation induced by CD1a restricted T cells, which have been implicated as drivers of inflammation in common inflammatory skin conditions such as psoriasis, atopic dermatitis and contact dermatitis.

Data-driven dynamic profiles of tonic heat pain perception in pain-free volunteers are associated with differences in anandamide levels.

Our laboratory previously developed a method for assessing experimentally induced pain perception through a 2-min constant heat pain stimulation. However, the traditional analysis relying on group means struggles to interpret the considerable inter-individual variability due to the dynamic nature of the response. Recently, trajectory analysis techniques based on extended mixed models have emerged, providing insights into distinct response profiles. Notably, these methods have never been applied to pain paradigms before. Furthermore, various socio-demographic and neurobiological factors, including endocannabinoids, may account for these inter-individual differences. This study aims to apply the novel analysis to dynamic pain responses and investigate variations in response profiles concerning socio-demographic, psychological, and blood endocannabinoid concentrations. 346 pain-free participants were enrolled in a psychophysical test involving a continuous painful heat stimulation lasting for 2 min at a moderate intensity. Pain perception was continuously recorded using a computerized visual scale. Dynamic pain response analyses were conducted using the innovative extended mixed model approach. In contrast to the traditional group-mean analysis, the extended mixed model revealed three pain response trajectories. Trajectory 1 is characterized by a delay peak pain. Trajectory 2 is equivalent to the classic approach (peak pain follow by a constant and moderate increase of pain perception). Trajectory 3 is characterized by extreme responses (steep peak pain, decrease, and increase of pain perception), Furthermore, age and blood anandamide levels exhibited significant variations among these three trajectories. Using an innovative statistical approach, we found that a large proportion of our sample had a response significantly different from the average expected response. Endocannabinoid system seems to play a role in pain response profile.

Altered levels of phospholipases C, diacylglycerols, endocannabinoids, and N-acylethanolamines in patients with hereditary angioedema due to FXII mutation.

BACKGROUND: Hereditary angioedema (HAE) is a rare genetic disorder characterized by local, self-limiting edema due to temporary increase in vascular permeability. HAE with normal C1 esterase inhibitor (C1INH) activity includes the form with mutations in the F12 gene encoding for coagulation factor XII (FXII-HAE) causing an overproduction of bradykinin (BK) leading to angioedema attack. BK binding to B2 receptors (BK2R) leads to an activation of phospholipase C (PLC) and subsequent generation of second messengers: diacylglycerols (DAGs) and possibly the endocannabinoids (eCBs), 2-arachidonoylglycerol (2-AG) and anandamide (AEA), and eCB-related N-acylethanolamines [palmitoylethanolamide (PEA) and oleoylethanolamide (OEA)]. To date, there are no data on the role of these lipid mediators in FXII-HAE. METHODS: Here, we analyzed plasma levels of PLC, DAGs, and eCBs in 40 patients with FXII-HAE and 40 sex- and age-matched healthy individuals. RESULTS: Plasma PLC activity was increased in FXII-HAE patients compared to controls. Concentrations of DAG 18:1-20:4, a lipid second messenger produced by PLC, were higher in FXII-HAE compared to controls, and positively correlated with PLC activity and cleaved high molecular kininogen (cHK). Also the concentrations of the DAG metabolite, 2-AG were altered in FXII-HAE. AEA and OEA were decreased in FXII-HAE patients compared to controls; by contrast, PEA, was increased. The levels of all tested mediators did not differ between symptomatic and asymptomatic patients. Moreover, C1INH-HAE patients had elevated plasma levels of PLC, which correlated with cHK, but the levels of DAGs and eCBs were the same as controls. CONCLUSIONS: BK overproduction and BKR2 activation are linked to alteration of PLCs and their metabolites in patients with FXII-HAE. Our results may pave way to investigations on the functions of these mediators in the pathophysiology of FXII-HAE, and provide new potential biomarkers and therapeutic targets.

Anandamide Modulates Thermal Avoidance in Caenorhabditis elegans Through Vanilloid and Cannabinoid Receptor Interplay.

Understanding the endocannabinoid system in C. elegans may offer insights into basic biological processes and potential therapeutic targets for managing pain and inflammation in human. It is well established that anandamide modulates pain perception by binding to cannabinoid and vanilloid receptors, regulating neurotransmitter release and neuronal activity. One objective of this study was to demonstrate the suitability of C. elegans as a model organism for assessing the antinociceptive properties of bioactive compounds and learning about the role of endocannabinoid system in C. elegans. The evaluation of the compound anandamide (AEA) revealed antinociceptive activity by impeding C. elegans nocifensive response to noxious heat. Proteomic and bioinformatic investigations uncovered several pathways activated by AEA. Enrichment analysis unveiled significant involvement of ion homeostasis pathways, which are crucial for maintaining neuronal function and synaptic transmission, suggesting AEA's impact on neurotransmitter release and synaptic plasticity. Additionally, pathways related to translation, protein synthesis, and mTORC1 signaling were enriched, highlighting potential mechanisms underlying AEA's antinociceptive effects. Thermal proteome profiling identified NPR-32 and NPR-19 as primary targets of AEA, along with OCR-2, Cathepsin B, Progranulin, Transthyretin, and ribosomal proteins. These findings suggest a complex interplay between AEA and various cellular processes implicated in nociceptive pathways and inflammation modulation. Further investigation into these interactions could provide valuable insights into the therapeutic potential of AEA and its targets for the management of pain-related conditions.

The relaxation effect of endocannabinoid anandamide on isolated rat bladder and vas deferens tissues and possible mechanisms.

BACKGROUND: The endocannabinoid system plays important roles in various systems, including the genitourinary system; however, its mechanism of action is not fully understood. OBJECTIVES: This study aimed to investigate the direct relaxant effects of anandamide and its possible mechanisms in isolated rat bladder and vas deferens tissues. METHODS: Twenty-one adult male Wistar albino rats were used. Bladder and vas deferens (prostatic and epididymal portions) tissues were mounted in 10 mL of organ baths. Relaxation responses to anandamide were recorded at 3 and 10 µM concentrations. After the rest period, the procedures were repeated in the presence of cannabinoid (CB) and vanilloid receptor antagonists, various potassium channel blockers, cyclo-oxygenase, and nitric oxide synthase inhibitors. In different tissues to investigate the Ca2+-channel antagonistic effect of anandamide, concentration-response curves to CaCl2 were obtained in the absence and presence of anandamide. RESULTS: Anandamide caused a significant relaxation response in the bladder and epididymal vas deferens tissues, but not in the prostatic portion. The effect of anandamide was antagonized in the presence of the CB1 antagonist AM251 or the non-selective potassium channel blocker tetraethylammonium in bladder tissue. In the epididymal vas deferens, anandamide significantly inhibited the calcium contraction responses, especially at high concentrations. The CB2 antagonist AM630 reversed this inhibition. CONCLUSIONS: The results show that anandamide has a direct relaxant effect on the isolated rat bladder and epididymal vas deferens. Anandamide triggers different mechanisms in different types of tissues, and further studies are needed to elucidate the mechanism of action of anandamide.

Absence of Evidence for Sustained Effects of Daily Cannabidiol Administration on Anandamide Plasma Concentration in Individuals with Cocaine Use Disorder: Exploratory Findings from a Randomized Controlled Trial.

Background: Cannabidiol (CBD) has been proposed to have a therapeutic potential over a wide range of neuropsychiatric disorders, including substance use disorders. Pre-clinical evidence suggests that CBD can increase anandamide (AEA) plasma concentration, possibly mediating some of its therapeutic properties. Whether CBD exerts such an effect on AEA in individuals with cocaine use disorder (CUD) remains unknown. Aims: To explore the sustained effects of daily CBD administration on AEA plasma concentrations compared with placebo in CUD. Methods: We used data from a randomized, double-blind, placebo-controlled trial evaluating CBD's efficacy in CUD. Seventy-eight individuals were randomized to receive a daily oral dose of 800 mg CBD (n = 40) or a placebo (n = 38). Participants stayed in an inpatient detoxification setting for 10 days, after which they were followed in an outpatient setting for 12 weeks. AEA plasma concentration was measured at baseline and at 23-h post CBD ingestion on day 8 and week 4. A generalized estimating equation model was used to assess CBD's effects on AEA, and sensitivity analyses were computed using Bayesian linear regressions. Results: Sixty-four participants were included in the analysis. Similar mean AEA plasma concentrations in both treatment groups (p = 0.357) were observed. At day 8, mean AEA plasma concentrations (± standard deviation) were 0.26 (± 0.07) ng/mL in the CBD group and 0.29 (± 0.08) ng/mL in the placebo group (p = 0.832; Bayes factor [BF] = 0.190). At week 4, they were 0.27 (± 0.09) ng/mL in the CBD group and 0.30 (± 0.09) ng/mL in the placebo group (p = 0.181; BF = 0.194). Conclusion: While not excluding any potential acute and short-term effect, daily CBD administration did not exert a sustained impact on AEA plasma concentrations in individuals with CUD compared with placebo. Registration: clinicaltrials.gov (NCT02559167).

Unraveling the Endocannabinoid System: Exploring Its Therapeutic Potential in Autism Spectrum Disorder.

The salient features of autism spectrum disorder (ASD) encompass persistent difficulties in social communication, as well as the presence of restricted and repetitive facets of behavior, hobbies, or pursuits, which are often accompanied with cognitive limitations. Over the past few decades, a sizable number of studies have been conducted to enhance our understanding of the pathophysiology of ASD. Preclinical rat models have proven to be extremely valuable in simulating and analyzing the roles of a wide range of established environmental and genetic factors. Recent research has also demonstrated the significant involvement of the endocannabinoid system (ECS) in the pathogenesis of several neuropsychiatric diseases, including ASD. In fact, the ECS has the potential to regulate a multitude of metabolic and cellular pathways associated with autism, including the immune system. Moreover, the ECS has emerged as a promising target for intervention with high predictive validity. Particularly noteworthy are resent preclinical studies in rodents, which describe the onset of ASD-like symptoms after various genetic or pharmacological interventions targeting the ECS, providing encouraging evidence for further exploration in this area.

Exploring the versatile roles of the endocannabinoid system and phytocannabinoids in modulating bacterial infections.

The endocannabinoid system (ECS), initially identified for its role in maintaining homeostasis, particularly in regulating brain function, has evolved into a complex orchestrator influencing various physiological processes beyond its original association with the nervous system. Notably, an expanding body of evidence emphasizes the ECS's crucial involvement in regulating immune responses. While the specific role of the ECS in bacterial infections remains under ongoing investigation, compelling indications suggest its active participation in host-pathogen interactions. Incorporating the ECS into the framework of bacterial pathogen infections introduces a layer of complexity to our understanding of its functions. While some studies propose the potential of cannabinoids to modulate bacterial function and immune responses, the outcomes inherently hinge on the specific infection and cannabinoid under consideration. Moreover, the bidirectional relationship between the ECS and the gut microbiota underscores the intricate interplay among diverse physiological processes. The ECS extends its influence far beyond its initial discovery, emerging as a promising therapeutic target across a spectrum of medical conditions, encompassing bacterial infections, dysbiosis, and sepsis. This review comprehensively explores the complex roles of the ECS in the modulation of bacteria, the host's response to bacterial infections, and the dynamics of the microbiome. Special emphasis is placed on the roles of cannabinoid receptor types 1 and 2, whose signaling intricately influences immune cell function in microbe-host interactions.

Characterization of a Fatty Acid Amide Hydrolase (FAAH) in Hirudo verbana.

The endocannabinoid system plays a critical role in modulating both peripheral and central nervous system function. Despite being present throughout the animal kingdom, there has been relatively little investigation of the endocannabinoid system beyond the traditional animal model systems. In this study, we report on the identification and characterization of a fatty acid aminohydrolase (FAAH) in the medicinal leech, Hirudo verbana. FAAH is the primary enzyme responsible for metabolizing the endocannabinoid signaling molecule arachidonoyl ethanolamide (anandamide or AEA) and therefore plays a critical role in regulating AEA levels in the nervous system. This Hirudo FAAH (HirFAAH) is expressed in the leech central nervous system (CNS) and is an orthologue of FAAH-2 observed in vertebrates. Functionally, HirFAAH has serine hydrolase activity based on activity-based protein profiling (ABPP) studies using the fluorophosphonate probe TAMRA-FP. HirFAAH also hydrolyzes arachidonyl 7-amino, 4-methyl coumarin amide (AAMCA), a substrate specific to FAAH. Hydrolase activity during both the ABPP and AAMCA assays was eliminated by mutation at a conserved activity-binding site. Activity was also blocked by the known FAAH inhibitor, URB597. Treatment of Hirudo ganglia with URB597 potentiated synapses made by the pressure-sensitive mechanosensory neuron (P cell), mimicking the effects of exogenously applied AEA. The Hirudo CNS has been a useful system in which to study properties of endocannabinoid modulation of nociception relevant to vertebrates. Therefore, this characterization of HirFAAH is an important contribution to comparative studies of the endocannabinoid system.

Cannabidiol improves maternal obesity-induced behavioral, neuroinflammatory and neurochemical dysfunctions in the juvenile offspring.

Maternal obesity is associated with an increased risk of psychiatric disorders such as anxiety, depression, schizophrenia and autism spectrum disorder in the offspring. While numerous studies focus on preventive measures targeting the mothers, only a limited number provide practical approaches for addressing the damages once they are already established. We have recently demonstrated the interplay between maternal obesity and treatment with cannabidiol (CBD) on hypothalamic inflammation and metabolic disturbances, however, little is known about this relationship on behavioral manifestations and neurochemical imbalances in other brain regions. Therefore, here we tested whether CBD treatment could mitigate anxiety-like and social behavioral alterations, as well as neurochemical disruptions in both male and female offspring of obese dams. Female Wistar rats were fed a cafeteria diet for 12 weeks prior to mating, and during gestation and lactation. Offspring received CBD (50 mg/kg) from weaning for 3 weeks. Behavioral tests assessed anxiety-like manifestations and social behavior, while neuroinflammatory and neurochemical markers were evaluated in the prefrontal cortex (PFC) and hippocampus. CBD treatment attenuated maternal obesity-induced anxiety-like and social behavioral alterations, followed by rescuing effects on imbalanced neurotransmitter and endocannabinoid concentrations and altered expression of glial markers, CB1, oxytocin and dopamine receptors, with important differences between sexes. Overall, the findings of this study provide insight into the signaling pathways for the therapeutic benefits of CBD on neuroinflammation and neurochemical imbalances caused by perinatal maternal obesity in the PFC and the hippocampus, which translates into the behavioral manifestations, highlighting the sexual dimorphism encompassing both the transgenerational effect of obesity and the endocannabinoid system.

Endocannabinoids and cortisol in plasma, aqueous and tear samples of primary angle closure glaucoma versus controls.

PURPOSE: To compare the levels of endocannabinoids (EC) in plasma, aqueous humor and tears, cortisol in plasma and aqueous, in primary angle closure glaucoma (PACG) and controls, while comparing the quality of life in both groups. METHODS: A total of 60 patients, ≥40years of age, with a diagnosis of PACG or cataract, 30 in each group were recruited. They were subjected to a detailed ophthalmic evaluation, a WHO Quality of Life Brief Version (WHOQOL-BREF) questionnaire answering and collection of tear, aqueous and blood samples. The levels of endocannabinoids-anandamide (AEA), 2-arachidonoylglycerol (2AG) in plasma, aqueous humor and tears; cortisol in plasma and aqueous humor; and WHO-QOL score in each group were noted. RESULTS: Plasma AEA (p = 0.01) and plasma 2-AG, (p = 0.002) levels were significantly higher in the control group as compared to the PACG group. WHO-QOL score was better in controls (p < 0.001). The EC were in undetectable levels in aqueous. Plasma and aqueous cortisol were significantly higher in PACG and both had the highest Area under the receiver operating characteristics (AUROC) curve value for differentiating PACG from controls. Tear 2AG and tear AEA had a moderately strong positive correlation with plasma 2-AG. Females had insignificantly higher levels of plasma and tear endocannabinoids. CONCLUSIONS: Tear endocannabinoids were determined for the first time in PACG and normal with no difference between the two groups. Plasma and aqueous cortisol levels are a differentiating factor between normal and glaucoma patients with plasma endocannabinoids being remarkably higher in normals. Quality of life in glaucoma patients with high cortisol levels is poorer.

Endocannabinoids and Stress-Related Neurospsychiatric Disorders: A Systematic Review and Meta-Analysis of Basal Concentrations and Response to Acute Psychosocial Stress.

Background: Dysregulation of the endocannabinoid (eCB) system is implicated in various stress-related neuropsychiatric disorders (SRDs), including anxiety, depression, and post-traumatic stress disorder (PTSD). In this systematic review and meta-analysis, our objectives were to characterize circulating anandamide (AEA) and 2-arachidonoylglycerol (2-AG) concentrations at rest and in response to acute laboratory-based psychosocial stress in individuals with SRDs and without (controls). Our primary aims were to assess the effects of acute psychosocial stress on eCB concentrations in controls (Aim 1), compare baseline (prestress) eCB concentrations between individuals with SRDs and controls (Aim 2), and explore differential eCB responses to acute psychosocial stress in individuals with SRDs compared with controls (Aim 3). Methods: On June 8, 2023, a comprehensive review of the MEDLINE (PubMed) database was conducted to identify original articles meeting inclusion criteria. A total of 1072, 1341, and 400 articles were screened for inclusion in Aims 1, 2, and 3, respectively. Results: Aim 1, comprised of seven studies in controls, revealed that most studies reported stress-related increases in AEA (86%, with 43% reporting statistical significance) and 2-AG (83%, though none were statistically significant except for one study in saliva). However, meta-analyses did not support these patterns (p's>0.05). Aim 2, with 20 studies, revealed that most studies reported higher baseline concentrations of both AEA (63%, with 16% reporting statistical significance) and 2-AG (60%, with 10% reporting statistical significance) in individuals with SRDs compared with controls. Meta-analyses confirmed these findings (p's<0.05). Aim 3, which included three studies, had only one study that reported statistically different stress-related changes in 2-AG (but not AEA) between individuals with PTSD (decrease) and controls (increase), which was supported by the meta-analysis (p<0.001). Meta-analyses showed heterogeneity across studies and aims (I2=14-97%). Conclusion: Despite substantial heterogeneity in study characteristics, samples, and methodologies, consistent patterns emerged, including elevated baseline AEA and 2-AG in individuals with SRDs compared with controls, as well as smaller stress-related increases in 2-AG in individuals with SRDs compared with controls. To consider eCBs as reliable biomarkers and potential intervention targets for SRDs, standardized research approaches are needed to clarify the complex relationships between eCBs, SRDs, and psychosocial stress.