Sex specific effects of the fatty acid amide hydrolase inhibitor URB597 on memory and brain β2-adrenergic and D1-dopamine receptors

The Role of Fatty Acid Amide Hydrolase, a Key Regulatory Endocannabinoid Enzyme, in Domain-Specific Cognitive Performance in Psychosis

BACKGROUND AND HYPOTHESIS

Cognitive impairments are particularly disabling for patients with a psychotic disorder and often persist despite optimization of antipsychotic treatment. Thus, motivating an extension of the research focus on the endocannabinoid system. The aim of this study was to evaluate group differences in brain fatty acid amid hydrolase (FAAH), an endocannabinoid enzyme between first-episode psychosis (FEP), individuals with clinical high risk (CHR) for psychosis and healthy controls (HCs). Furthermore, to test the hypothesis that FAAH is linked with cognition using positron emission tomography (PET).

STUDY DESIGN

We analyzed 80 PET scans with the highly selective FAAH radioligand [11C]CURB, including 30 patients with FEP (6 female), 15 CHR (5 female), and 35 HC (19 female). The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Berg Card Sorting Test (BCST) were applied to test cognitive performance.

STUDY RESULTS

There was no difference in FAAH activity between groups (F2, 75 = 0.75, P = .48; Cohen's f = 0.141; small effect). Overall, there was a difference in the association between groups regarding FAAH activity and the domain visuospatial construction (F2, 72 = 4.67, P = .01; Cohen's f = .36; medium effect). Furthermore, across the sample, lower FAAH activity was associated with a higher percentage of perseverative responses (F1, 66 = 5.06, P = .03; Cohen's f = 0.28, medium effect).

CONCLUSIONS

We report evidence for associations between endocannabinoid alterations in FEP and CHR with specific domains of cognition (visuospatial construction and perseverative response), not overall cognition.

Formoterol dynamically alters endocannabinoid tone in the periaqueductal gray inducing headache

BACKGROUND

Headache is a pain disorder present in populations world-wide with a higher incidence in females. Specifically, the incidences of medication overuse headache (MOH) have increased worldwide. Comorbidities of MOH include photosensitivity, anxiety, "brain fog", and decreased physical activity. The FDA-approved long-lasting selective β2-adrenergic receptor agonist, formoterol, is currently approved for use in severe asthma and chronic obstructive pulmonary disease. Recently, interest in repurposing formoterol for use in other disorders including Alzheimer's disease, and neuropathic pain after spinal cord injury and traumatic brain injury has gained traction. Thus, revisiting known side-effects of formoterol, like headache and anxiety, could inform treatment paradigms. The endocannabinoid (eCB) system is implicated in the etiology of preclinical headache, with observed decreases in the circulating levels of endogenous cannabinoids, referred to as Clinical Endocannabinoid Deficiency. As cross-talk between the eCB system and adrenergic receptors has been reported, this study investigated the role of the eCB system and ability of formoterol to induce headache-like periorbital allodynic behavior.

METHODS

Female 8-week-old C57Bl/6J mice were treated daily with formoterol (0.3 mg/kg, i.p.) for up to 42-days, during which they were assessed for periorbital allodynia, open field/novel object recognition, and photosensitivity. At the end of the study, the periaqueductal grey (PAG), a brain region known to contribute to both headache induction and maintenance, was collected and subjected to LC-MS to quantify endocannabinoid levels.

RESULTS

Mice exhibited periorbital allodynia at nearly all time points tested and photosensitivity from 28-days onward. Levels of endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), along with cannabinoid receptor 1 (CB1R) expression were altered by both age and upon treatment with formoterol. Administration of FAAH/MAGL inhibitors, to target the eCB system, and a non-selective cannabinoid receptor agonist, WIN 55,212 reversed the formoterol-induced periorbital allodynia.

CONCLUSIONS

These results suggest that formoterol is dysregulates eCB tone to drive headache-like periorbital allodynic behaviors. These results could help inform preventative treatment options for individuals receiving formoterol, as well as provide information on the interaction between the eCB and adrenergic system.

Sex-Related and Brain Regional Differences of URB597 Effects on Modulation of MAPK/PI3K Signaling in Chronically Stressed Rats

Gender differences exist in depression incidence and antidepressant efficacy. In addition to the neurotransmission theory of depression, inflammation and disrupted signaling pathways play crucial roles in the pathophysiology of depression. Endocannabinoids offer a novel approach to treat inflammatory and emotional disorders like depression. URB597, a FAAH inhibitor, reduces endocannabinoids breakdown. In this study, URB597 effects were investigated on the pro-inflammatory cytokine interleukin-1β (IL-1β), nucleotide binding and oligomerization domain-like receptor family pyrin domain-containing 3(NLRP3), and mitogen-activated protein kinase (MAPK)/ phosphatidylinositol 3-hydroxy kinase/ protein kinase B (PI3K) signaling in the hippocampus and the medial prefrontal cortex (mPFC) of male and female rats subjected to chronic unpredictable stress (CUS). The results show that CUS induces depression-like behaviors, and the URB597 exhibited antidepressant-like effects inboth sexes. URB597 reduced the CUS-induced NLRP3 and IL-1β increase in the hippocampus and mPFC of both sexes. URB597 increased the reduced pERK1/2 levels in the mPFC of both sexes and hippocampus of CUS males. URB597 also prevented the increase in p38 phosphorylation after chronic stress in the mPFC of both sexes and in the hippocampus of the females. The CUS suppressed the downstream Akt phosphorylation in the mPFC and hippocampi of both sexes. URB597 produced an up-regulation of the pAkt in the hippocampus of the CUS animals but did not affect the pAkt in the mPFC. These data demonstrated a sexual dimorphism in the neural cell signaling, and in the effects of endocannabinoids, and indicated these dimorphisms are region-specific.

Exploring the Value of MRI Measurement of Hippocampal Volume for Predicting the Occurrence and Progression of Alzheimer's Disease Based on Artificial Intelligence Deep Learning Technology and Evidence-Based Medicine Meta-Analysis

BACKGROUND

Alzheimer's disease (AD), a major dementia cause, lacks effective treatment. MRI-based hippocampal volume measurement using artificial intelligence offers new insights into early diagnosis and intervention in AD progression.

OBJECTIVE

This study, involving 483 AD patients, 756 patients with mild cognitive impairment (MCI), and 968 normal controls (NC), investigated the predictive capability of MRI-based hippocampus volume measurements for AD risk using artificial intelligence and evidence-based medicine.

METHODS

Utilizing data from ADNI and OASIS-brains databases, three convolutional neural networks (InceptionResNetv2, Densenet169, and SEResNet50) were employed for automated AD classification based on structural MRI imaging. A multitask deep learning model and a densely connected 3D convolutional network were utilized. Additionally, a systematic meta-analysis explored the value of MRI-based hippocampal volume measurement in predicting AD occurrence and progression, drawing on 23 eligible articles from PubMed and Embase databases.

RESULTS

InceptionResNetv2 outperformed other networks, achieving 99.75% accuracy and 100% AUC for AD-NC classification and 99.16% accuracy and 100% AUC for MCI-NC classification. Notably, at a 512×512 size, InceptionResNetv2 demonstrated a classification accuracy of 94.29% and an AUC of 98% for AD-NC and 97.31% accuracy and 98% AUC for MCI-NC.

CONCLUSIONS

The study concludes that MRI-based hippocampal volume changes effectively predict AD onset and progression, facilitating early intervention and prevention.

The neural basis underlying female vulnerability to depressive disorders

Depressive disorders are more prevalent and severe in women; however, our knowledge of the underlying factors contributing to female vulnerability to depression remains limited. Additionally, females are notably underrepresented in studies seeking to understand the mechanisms of depression. Various animal models of depression have been devised, but only recently have females been included in research. In this comprehensive review, we aim to describe the sex differences in the prevalence, pathophysiology, and responses to drug treatment in patients with depression. Subsequently, we highlight animal models of depression in which both sexes have been studied, in the pursuit of identifying models that accurately reflect female vulnerability to depression. We also introduce explanations for the neural basis of sex differences in depression. Notably, the medial prefrontal cortex and the nucleus accumbens have exhibited sex differences in previous studies. Furthermore, other brain circuits involving the dopaminergic center (ventral tegmental area) and the serotonergic center (dorsal raphe nucleus), along with their respective projections, have shown sex differences in relation to depression. In conclusion, our review covers the critical aspects of sex differences in depression, with a specific focus on female vulnerability in humans and its representation in animal models, including the potential underlying mechanisms. Employing suitable animal models that effectively represent female vulnerability would benefit our understanding of the sex-dependent pathophysiology of depression.

The FAAH inhibitor URB597 reduces cocaine intake during conditioned punishment and mitigates cocaine seeking during withdrawal

The endocannabinoid system is prominently implicated in the control of cocaine reinforcement due to its relevant role in synaptic plasticity and neurotransmitter modulation in the mesocorticolimbic system. The inhibition of fatty acid amide hydrolase (FAAH), and the resulting increase in anandamide and other N-acylethanolamines, represents a promising strategy for reducing drug seeking. In the present study, we aimed to assess the effects of the FAAH inhibitor URB597 (1 mg/kg) on crucial features of cocaine addictive-like behaviour in mice. Therefore, we tested the effects of URB597 on acquisition of cocaine (0.6 mg/kg/inf) self-administration, compulsive-like cocaine intake and cue-induced drug-seeking behaviour during withdrawal. URB597 reduced cocaine intake under conditioned punishment while having no impact on acquisition. This result was associated to increased cannabinoid receptor 1 gene expression in the ventral striatum and medium spiny neurons activation in the nucleus accumbens shell. Moreover, URB597 mitigated cue-induced drug-seeking behaviour during prolonged abstinence and prevented the withdrawal-induced increase in FAAH gene expression in the ventral striatum. In this case, URB597 decreased activation of medium spiny neurons in the nucleus accumbens core. Our findings evidence the prominent role of endocannabinoids in the development of cocaine addictive-like behaviours and support the potential of FAAH inhibition as a therapeutical target for the treatment of cocaine addiction.

Psychological distress influences lung cancer: Advances and perspectives on the immune system and immunotherapy

Lung cancer has the highest incidence rate and mortality worldwide. Moreover, multiple factors may cause heterogeneity in the efficacy of immunotherapy for lung cancer, and preclinical studies have gradually uncovered the promotive effects of psychological distress (PD) on tumor hallmarks. Therefore, treatment targeted at PD may be a vital factor in adjusting and improving immunotherapy for lung cancer. Here, by focusing on the central nervous system, as well as stress-related crucial neurotransmitters and hormones, we highlight the effects of PD on the lung immune system, the lung tumor microenvironment (TME) and immunotherapy, which brings a practicable means and psychosocial perspective to lung cancer treatment.