Placental complications resulting in fetal growth restriction have been associated with dysregulated placental gene expression tied to an increased risk of schizophrenia. In rat offspring, it has been demonstrated that ∆9-tetrahydrocannabinol exposure in pregnancy results in fetal growth restriction and schizophrenia-like phenotypes (e.g., decreased pre-pulse inhibition of the acoustic startle response). However, it remains elusive if prenatal ∆9-tetrahydrocannabinol exposure induces this schizophrenia signature of placental gene expression. Therefore, our objective was to determine if these established predictive markers of schizophrenia are altered in a preclinical model of gestational oral ∆9-tetrahydrocannabinol exposure in rodents. We observed significantly reduced fetal weights in male and female prenatal ∆9-tetrahydrocannabinol-exposed offspring in the absence of maternal pregnancy outcomes. Placentae from ∆9-tetrahydrocannabinol-exposed males and females revealed altered expression of genes previously identified in human transcriptomic datasets of schizophrenia (i.e., Furin, Rccd1, and Atp5mk), with some expression changes being sex-specific (i.e., Eif5, Rps10, Vps33b, and Iqgap1). A subset of these genes were found differentially expressed in human BeWo cells exposed to ∆9-tetrahydrocannabinol. Targets were next examined in the adult rodent (postnatal day70) brain, and a subgroup of these genes (i.e., Furin, Rps10, and Rccd1) were increased concomitant with schizophrenia-like behavior (e.g., decreased pre-pulse inhibition). We further detected ∆9-tetrahydrocannabinol-induced upregulation of FURIN in patient-derived cerebral organoids, an effect observed in both control and schizophrenia cell lines. Collectively, these findings demonstrate prenatal ∆9-tetrahydrocannabinol exposure can lead to altered gene expression in established prioritized markers of schizophrenia in the placenta in both animal and human models.
Chronic cannabis during adolescence is associated with long-lasting pathological outcomes, and these effects can be remarkably different between the sexes. Preclinical studies in rodents demonstrated that sustained exposure to Δ9-tetrahydrocannabinol (THC), induces sex-specific pathophysiological outcomes. Thus, while males exhibit higher vulnerability to schizophrenia-like manifestations and cognitive impairments, females show greater susceptibility to emotional dysregulations and selective memory deficits. This study aimed to explore the long-lasting impact of adolescent THC exposure in female rats and to identify mechanisms underlying these potential THC-related effects. We treated adolescent female rats from postnatal day (PND) 35 to 45 with increasing doses of THC. At adulthood (PND 75), we carried out a battery of behavioral tasks to assess locomotion, sensorimotor gating deficits, memory impairments, and anxiety. Furthermore, we examined molecular biomarkers in several local brain regions relevant to THC-related pathology as well as the neuronal activity states of putative glutamatergic cells in the dorsal and ventral subiculum and their associated oscillatory patterns. We report that adolescent female rats exposed to THC gained weight slower than controls during the treatment period. In adulthood, they did not exhibit any observable behavioral abnormalities in the chosen tests. However, we observed long-lasting adaptations in estrogen receptor-α (ERα) and fatty acid amid hydrolase (FAAH) expression levels in the hypothalamus and hippocampus and enduring alterations in hippocampal oscillatory patterns. These findings provide evidence that female rats exhibit sex-specific adaptations following adolescent THC exposure, which may confer protection against long-term behavioural abnormalities consistently observed in male cohorts.
Prenatal Δ9-tetrahydrocannabinol exposure (PTE) poses long-lasting neuropsychiatric risks, as evidenced by clinical and preclinical studies, yet the neurobiological mechanisms remain poorly defined. Emerging evidence implicates the neurolipidome, a critical mediator of neurodevelopment and endocannabinoid signaling, as a potential contributor. Here, we demonstrate that dietary omega-3 fatty acid supplementation sex-selectively ameliorates neurodevelopmental deficits induced by PTE in a Wistar rat model. Omega-3 supplementation reduced cognitive and emotional disturbances in male offspring and normalized many neuronal and neurochemical abnormalities in the prefrontal cortex, nucleus accumbens, and ventral hippocampus. However, lipidomic analyses, regardless of omega-3 supplementation, uncovered pronounced, sex-specific PTE-induced disruptions in pathways critical for synaptic integrity and neurodevelopment, including those related to the endocannabinoid system. These findings provide new insights into the interplay between lipid metabolism and the endocannabinoid system in the context of PTE.
Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is a powerful tool for tissue lipid analysis. Yet, the validity of fatty acid (FA) signals is often questioned due to the potential of in-source lipid fragmentation. This study investigates the extent of in-source phospholipid fragmentation by examining different phospholipid headgroups, specifically phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylserine (PS) and phosphatidylcholine (PC), containing a mix of saturated and unsaturated tails, comparing in-source fragmentation of FA tails. These standards evaluated phospholipid fragmentation during laser intensity optimization for MALDI-MS and MSI. Fragmentation was assessed in negative ion mode using four MALDI matrices: norharmane (NRM), 9-aminoacridine (9AA), 1,5-diaminonaphthalene (DAN), and 1,6-diphenyl-1,3,5-hexatriene (DPH). By examining the extent of in-source fragmentation during MALDI MSI, an exogenous standard can be chosen to monitor in-source fragmentation during experiments. Various techniques for standard deposition were evaluated, including manual spotting versus automated spraying and pre-depositing standards beneath tissue sections compared to applying them directly onto tissue surfaces. The results demonstrate the ability of these phospholipid standards to detect in-source fragmentation using different matrices, as demonstrated by the detection of the exogenous FA 17:0 tail signal. Furthermore, the study highlights the importance of selecting a standard that closely matches the lipid of interest to optimize laser energy for MSI, enhancing endogenous FA signals while minimizing in-source fragmentation. This work provides a workflow for mitigating in-source fragmentation in MALDI-MSI experiments, enabling more reliable lipid analysis in complex biological tissues.
Cannabis use in pregnancy is associated with low birthweight outcomes. Recent preclinical data suggests that maternal Δ9-tetrahydrocannabinol (THC) exposure leads to decreases in birthweight followed by early cardiac deficits in offspring. Currently, no studies have explored an intervention for these maternal THC-induced deficits. Omega-3 fatty acids have been shown to exhibit cardioprotective effects. In this present study, we demonstrated that maternal dietary supplementation of omega-3 fatty acids ameliorates both THC-induced fetal growth and postnatal cardiac deficits in offspring. Our data indicates this may be underpinned by alterations in cardiac and hepatic fatty acids and reduction in markers of cardiac collagen deposition. Interestingly, the cardioprotective effects of omega-3s may be further underscored by decreased signaling of the cardiac endocannabinoid system. With increasing rates of cannabis use in pregnancy and recent evidence of subsequent cardiometabolic aberrations in offspring, our data suggests a potential intervention for THC-induced fetal growth and cardiac disturbances in offspring.
Maternal tobacco use during pregnancy (MTDP) remains a global and domestic public health issue. This study seeks to investigate the long-term impact of MTDP on brain morphology during late childhood and early adolescence using the Adolescent Brain Cognitive Development (ABCD) dataset. Children aged 9-10 were enrolled using the ABCD school selection probability sample method for national representation. Participants and their parents or guardians underwent interviews and surveys, and children underwent Magnetic Resonance Imaging (MRI) at baseline and 2-year follow-up. Morphometric brain measures of cortical thickness and sulcal depth across 34 regions of interest on T1-weighted MRI images were analyzed. Of 11,448 at baseline, 1607 children fell into the MTDP group. Intracranial volume (p < 0.001), total cortical surface area, and volume (p < 0.0001) were significantly lower among MTDP children (vs. control) at both waves 1 and 2. A sustained difference was found in mean cortical thickness at the parahippocampal gyrus as well as sulcal depth at the isthmus cingulate, parahippocampal, lateral occipital, and lingual gyri. Several regions of interest demonstrated differences in the cortical thickness and sulcal depth at single time points. An association between MTDP and long-term outcomes of regional morphometric differences in cortical thickness and sulcal depth on MRI was found at both baseline among 9-10 years old and at 2-year follow-ups. Taken together with NIH cognitive testing from the same population comparison, the results suggest longstanding cognitive deficits corresponding to specific brain regions.
Anxiety and mood disorders represent the most prevalent neuropsychiatric conditions. Nevertheless, current pharmacotherapies often have a host of adverse side effects. Emerging evidence suggests modulation of lipid signaling pathways - particularly those involved in the endocannabinoid (eCB) system, may offer promising new targets for the treatment of anxiety and depression. Polyunsaturated fatty acids (PUFA) and their metabolic derivatives, including the eCB ligands, have garnered significant attention for their roles in neuropsychiatric disease mechanisms. Intracellular transportation of these lipids is facilitated by fatty acid binding proteins (FABP), which are increasingly recognized as key regulators of lipid signaling. Accumulating evidence indicates that FABPs may impact the development of neuropsychiatric disorders by mediating the signaling pathways of PUFAs and eCB ligands. In this review, we investigate the role of FABPs in two major categories of neuropsychiatric conditions - anxiety disorders and clinical depression. We begin by examining several neuropathophysiological mechanisms through which FABPs can impact these conditions, focusing on their role as lipid chaperones. These mechanisms include the trafficking of eCB ligands, as well as oleoylethanolamide and palmitoylethanolamide; modulation of inflammatory responses through PUFA transport and PPAR activation; regulation of PUFA availability to support neurogenesis; influence on stress-related pathways, including NMDA receptor activation and the hypothalamic-pituitary-adrenal axis; and the facilitation of dopamine receptor trafficking and localization. Next, we discuss preclinical evidence linking FABP function to anxiety- and depression-related behaviours. Finally, we propose that pharmacologically targeting FABP-mediated pathways holds considerable potential as a novel therapeutic strategy for addressing the symptoms associated with mood and anxiety disorders.
Clinical and pre-clinical research has reported promising outcomes for cannabidiol (CBD) in treating mood and anxiety disorder symptoms. However, the pharmacokinetic properties of CBD, such as low and variable bioavailability and low aqueous solubility, limit its therapeutic applications. This study investigated the effects of ART12.11, a novel cannabidiol:tetramethylpyrazine (CBD:TMP) cocrystal, that aims to improve the pharmacotherapeutic potential of CBD by combining it with the co-former tetramethylpyrazine (TMP) to improve CBD's pharmaceutical properties. We used an integrative combination of translational behavioural pharmacology alongside targeted gene and protein expression analyses to characterize the potential anti-depressant and anxiolytic-like effects of ART12.11 in male Sprague Dawley rats, following exposure to chronic stress. In addition, we investigated blood plasma concentrations of CBD and TMP following oral administration of ART12.11 to examine bioavailability. We report that oral administration of ART12.11 reversed stress-induced behavioural deficits and produced significant anti-depressant and anxiolytic-like behavioural effects, which were superior to oral administration of CBD alone, TMP alone, or the co-administration of a non-crystalline mixture of CBD and TMP. Further, we report that ART12.11 resulted in higher blood plasma levels of CBD and its major metabolite, indicating superior bioavailability. Finally, we demonstrate that ART12.11 increased activation of the endocannabinoid and serotonergic systems directly in the prefrontal cortex, ventral hippocampus, and nucleus accumbens. Collectively, our findings indicate that ART12.11 may offer significant advantages over delivering CBD by more traditional approaches in the treatment of mood and anxiety disorders.
The endocannabinoid (eCB) system modulates many biological processes, including adult neurogenesis, emotional behaviour and stress-related signaling pathways. Intrinsic levels of eCB ligands, such as anandamide, are regulated in part, by fatty acid binding protein 5 (FABP5), a chaperone protein that transports anandamide for hydrolysis. Here, using preclinical rodent models, we examined the effects of pharmacological FABP5 inhibition on anxiety- and depressive-like behaviours and associated molecular signaling pathways, following exposure to chronic stress. In addition, we investigated the impacts of chronic stress on hippocampal neurogenesis and how FABP5 inhibition may modulate stress-induced deficits in hippocampal neurogenic mechanisms. Remarkably, we report that anxiety- and depressive-like behaviours are strongly prevented by systemic FABP5 inhibition and associated with altered transcription of IGF-1, CB2 and GPR55 receptors as well as by altered phosphorylation of Erk1/2, Akt and p70S6 kinase pathways in the limbic circuitry. Finally, FABP5 inhibition potently blocked stress-induced reductions in hippocampal neurogenesis, identifying FABP5 inhibition as a promising pharmacotherapeutic candidate for stress-induced mood and anxiety symptoms.
Clinical and pre-clinical evidence demonstrates that adolescent Δ-9-tetrahydrocannabinol (THC) exposure, the primary psychoactive component of cannabis, increases the risk of developing neuropsychiatric symptoms in later life. The medial prefrontal cortex (mPFC) serves as a pathophysiological nexus point underlying many cannabis-related pathophysiological outcomes. Nevertheless, the molecular mechanisms underlying these risk factors are poorly understood. THC increases oxidative stress, which is a well-established causal factor for increased neuropsychiatric risk, including schizophrenia. N-acetylcysteine (NAC) is an antioxidant glutathione precursor that normalizes glutamate and GABA activity in neuropathological states. We examined if NAC may prevent the pathophysiological impacts of THC using a rodent model of adolescent brain development and chronic THC exposure. We report that NAC treatment prevents cognitive, synaptic, neuronal and neurochemical deficits induced by adolescent THC. These findings highlight the critical role of THC-induced oxidative stress as a contributing factor to cannabinoid-mediated neuropsychiatric risk and identifies a novel antioxidant treatment candidate for the prevention and/or reversal of these pathophysiological outcomes.
The majority of lifetime smokers begin using nicotine during adolescence, a critical period of brain development wherein neural circuits critical for mood, affect and cognition are vulnerable to drug-related insults. Specifically, brain regions such as the medial prefrontal cortex (mPFC), the ventral tegmental area (VTA), nucleus accumbens (NAc) and hippocampus, are implicated in both nicotine dependence and pathological phenotypes linked to mood and anxiety disorders. Clinical studies report that females experience higher rates of mood/anxiety disorders and are more resistant to smoking cessation therapies, suggesting potential sex-specific responses to nicotine exposure and later-life neuropsychiatric risk. However, the potential neural and molecular mechanisms underlying such sex differences are not clear. In the present study, we compared the impacts of adolescent nicotine exposure in male vs. female rat cohorts. We performed a combination of behavioral, electrophysiological and targeted protein expression analyses along with matrix assisted laser deionization imaging (MALDI) immediately post-adolescent exposure and later in early adulthood. We report that adolescent nicotine exposure induced long-lasting anxiety/depressive-like behaviors, disrupted neuronal activity patterns in the mPFC-VTA network and molecular alterations in various neural regions linked to affect, anxiety and cognition. Remarkably, these phenotypes were only observed in males and/or were expressed in the opposite direction in females. These findings identify a series of novel, sex-selective biomarkers for adolescent nicotine-induced neuropsychiatric risk, persisting into adulthood.
Reports in North America suggest that up to 20% of young women (18–24 years) use cannabis during pregnancy. This is concerning given clinical studies indicate that maternal cannabis use is associated with fetal growth restriction and dysglycemia in the offspring. Preclinical studies demonstrated that prenatal exposure to Δ9-tetrahydrocannabinol, the main psychoactive component of cannabis, in rat dams led to female-specific deficits in β-cell mass and glucose intolerance/insulin resistance. Yet to date, the contributions of cannabidiol (CBD), the primary nonpsychoactive compound in cannabis, remain elusive. This study aimed to define the effects of in utero cannabidiol (CBD) exposure on postnatal glucose regulation. Pregnant Wistar rat dams received daily intraperitoneal injections of either a vehicle solution or 3 mg/kg of CBD from gestational day (GD) 6 to parturition. CBD exposure did not lead to observable changes in maternal or neonatal outcomes; however, by 3 months of age male CBD-exposed offspring exhibited glucose intolerance despite no changes in pancreatic β/α-cell mass. Transcriptomic analysis on the livers of these CBD-exposed males revealed altered gene expression of circadian rhythm clock machinery, which is linked to systemic glucose intolerance. Furthermore, alterations in hepatic developmental and metabolic processes were also observed, suggesting gestational CBD exposure has a long-lasting detrimental effect on liver health throughout life. Collectively, these results indicate that exposure to CBD alone in pregnancy may be detrimental to the metabolic health of the offspring later in life.
Clinical and preclinical evidence has demonstrated an increased risk for neuropsychiatric disorders following prenatal cannabinoid exposure. However, given the phytochemical complexity of cannabis, there is a need to understand how specific components of cannabis may contribute to these neurodevelopmental risks later in life. To investigate this, a rat model of prenatal cannabinoid exposure was utilized to examine the impacts of specific cannabis constituents (Δ9-tetrahydrocannabinol [THC]; cannabidiol [CBD]) alone and in combination on future neuropsychiatric liability in male and female offspring. Prenatal THC and CBD exposure were associated with low birth weight. At adolescence, offspring displayed sex-specific behavioural changes in anxiety, temporal order and social cognition, and sensorimotor gating. These phenotypes were associated with sex and treatment-specific neuronal and gene transcriptional alterations in the prefrontal cortex, and ventral hippocampus, regions where the endocannabinoid system is implicated in affective and cognitive development. Electrophysiology and RT-qPCR analysis in these regions implicated dysregulation of the endocannabinoid system and balance of excitatory and inhibitory signalling in the developmental consequences of prenatal cannabinoids. These findings reveal critical insights into how specific cannabinoids can differentially impact the developing fetal brains of males and females to enhance subsequent neuropsychiatric risk.
Introduction: Studies indicate that ∼7% of pregnant individuals in North America consume cannabis in pregnancy. Pre-clinical studies have established that maternal exposure to Δ9-tetrahydrocannabinol (THC; major psychoactive component in cannabis) leads to fetal growth restriction and impaired cardiac function in offspring. However, the effects of maternal exposure to cannabidiol (CBD; major non-euphoric constituent) on cardiac outcomes in offspring remain unknown. Therefore, our objective is to investigate the functional and underlying molecular impacts in the hearts of offspring exposed to CBD in pregnancy. Methods: Pregnant Wistar rats were exposed to either 3 or 30 mg/kg CBD or vehicle control i.p. daily from gestational day 6 to term. Echocardiography was used to assess cardiac function in male and female offspring at postnatal day (PND) 21. Furthermore, quantitative polymerase chain reaction (qPCR), immunoblotting, and bulk RNA-sequencing (RNA-seq) were performed on PND21 offspring hearts. Results: Despite no differences in the heart-to-body weight ratio, both doses of CBD led to reduced cardiac function exclusively in male offspring at 3 weeks of age. Underlying this, significant alterations in the expression of the endocannabinoid system (ECS; e.g., decreased cannabinoid receptor 2) were observed. In addition, bulk RNA-seq data demonstrated transcriptional pathways significantly enriched in mitochondrial function/metabolism as well as development. Conclusion: Collectively, we demonstrated for the first time that gestational exposure to CBD, a constituent perceived as safe, leads to early sex-specific postnatal cardiac deficits and alterations in the cardiac ECS in offspring.
Cannabis has shown therapeutic potential in mood and anxiety-related pathologies. However, the two primary constituents of cannabis, cannabidiol (CBD) and Δ-9-tetrahydrocannabinol (THC) produce distinct effects on molecular pathways in neural circuits associated with affective disorders. Moreover, it has been proposed that the combination of THC: and CBD may have unique synergistic properties. In the present study, the effects of a 1:100 THC: CBD ratio edible formulation were tested in behavioural, neuronal and molecular assays for anxiety and depressive-like endophenotypes. Adult male and female Sprague-Dawley rats were stressed for 14 days. Then, for three weeks, open field, elevated plus maze, light/dark box, social interaction, sucrose preference, and the forced swim test were performed 90 minutes after acute consumption of CBD (30 mg/kg), THC (0.3 mg/kg), or 1:100 combination of THC:CBD. After behavioural tests, in vivo, neuronal electrophysiological analyses were performed in the ventral tegmental area and prefrontal cortex (PFC). Furthermore, western-blot experiments examined the expression of biomarkers associated with mood and anxiety disorders, including protein kinase B (Akt), glycogen synthase kinase-3 (GSK-3), BDNF, mTOR, D1, and D2 receptor in nucleus accumbens (NAc) and PFC.Edible THC:CBD produces significant anxiolytic and antidepressant effects only in stressed male rats. In most cases, the combination of THC and CBD had stronger effects than either phytochemical alone. These synergistic effects are associated with alterations in Akt/GSK3 and D2-R expression in NAc and BDNF expression in PFC. Furthermore, THC:CBD reverses chronic stress-induced alterations in PFC neuronal activity. These findings demonstrate a novel synergistic potential for THC:CBD edible formulations in stress-related pathologies.
Background: Exposure to Δ9-tetrahydrocannabinol (THC) is an established risk factor for later-life neuropsychiatric vulnerability, including mood- and anxiety-related symptoms. The psychotropic effects of THC on affect and anxiogenic behavioral phenomena are known to target the striatal network, particularly the nucleus accumbens, a neural region linked to mood and anxiety disorder pathophysiology. THC may increase neuroinflammatory responses via the redox system and dysregulate inhibitory and excitatory neural balance in various brain circuits, including the striatum. Thus, interventions that can induce antioxidant effects may counteract the neurodevelopmental impacts of THC exposure. Methods: In the current study, we used an established preclinical adolescent rat model to examine the impacts of adolescent THC exposure on various behavioral, molecular, and neuronal biomarkers associated with increased mood and anxiety disorder vulnerability. Moreover, we investigated the protective properties of the antioxidant N-acetylcysteine against THC-related pathology. Results: We demonstrated that adolescent THC exposure induced long-lasting anxiety- and depressive-like phenotypes concomitant with differential neuronal and molecular abnormalities in the two subregions of the nucleus accumbens, the shell and the core. In addition, we report for the first time that N-acetylcysteine can prevent THC-induced accumbal pathophysiology and associated behavioral abnormalities. Conclusions: The preventive effects of this antioxidant intervention highlight the critical role of redox mechanisms underlying cannabinoid-induced neurodevelopmental pathology and identify a potential intervention strategy for the prevention and/or reversal of these pathophysiological sequelae.
IntroductionPrenatal nicotine exposure (PNE) from maternal smoking disrupts regulatory processes vital to fetal development. These changes result in long-term behavioral impairments, including mood and anxiety disorders, that manifest later in life. However, the relationship underlying PNE, and the underpinnings of mood and anxiety molecular and transcriptomic phenotypes remains elusive.MethodsTo model nicotine exposure during prenatal development, our study used human cerebral organoids that were chronically exposed to nicotine and collected for molecular analyses.ResultsShort-term, nicotine altered molecular markers of neural identity, mood and anxiety disorders and those involved in maintaining the excitatory/inhibitory (E/I) balance in the cortex. RNA sequencing further revealed transcriptomic changes in genes pertaining to embryonic development, neurogenesis, and DNA binding. Long-term, mature organoids demonstrated similar disruptions in E/I balance, decreased expression of neural identity markers, and altered dopamine receptor expression.DiscussionCollectively, our results demonstrate that nicotine-induced alterations occur acutely and persist at later stages of development. These findings validate an in vitro model of PNE to better comprehend the emergence of neuropsychiatric molecular and transcriptomic endophenotypes resulting from gestational nicotine exposure.
The endocannabinoid (eCB) system represents a promising neurobiological target for novel anxiolytic pharmacotherapies. Previous clinical and preclinical evidence has revealed that genetic and/or pharmacological manipulations altering eCB signaling modulate fear and anxiety behaviors. Water-insoluble eCB lipid anandamide requires chaperone proteins for its intracellular transport to degradation, a process that requires fatty acid-binding proteins (FABPs). Here, we investigated the effects of a novel FABP-5 inhibitor, SBFI-103, on fear and anxiety-related behaviors using rats. Acute intra-prelimbic cortex administration of SBFI-103 induced a dose-dependent anxiolytic response and reduced contextual fear expression. Surprisingly, both effects were reversed when a cannabinoid-2 receptor (CB2R) antagonist, AM630, was co-infused with SBFI-103. Co-infusion of the cannabinoid-1 receptor antagonist Rimonabant with SBFI-103 reversed the contextual fear response yet showed no reversal effect on anxiety. Furthermore, in vivo neuronal recordings revealed that intra-prelimbic region SBFI-103 infusion altered the activity of putative pyramidal neurons in the basolateral amygdala and ventral hippocampus, as well as oscillatory patterns within these regions in a CB2R-dependent fashion. Our findings identify a promising role for FABP5 inhibition as a potential target for anxiolytic pharmacotherapy. Furthermore, we identify a novel, CB2R-dependent FABP-5 signaling pathway in the PFC capable of strongly modulating anxiety-related behaviors and anxiety-related neuronal transmission patterns.