WIN55,212-2, a Dual Modulator of Cannabinoid Receptors and G Protein-Coupled Inward Rectifier Potassium Channels

A549 cells exposed to a marijuana smoke extract affect mono-layer integrity related to oxidative stress state

Marijuana smoke contains several toxic compounds that may induce dysregulation of oxidative mechanisms and barrier system in airway alveolar cells. This study aimed to assess whether marijuana smoke extract (MSE) modifies mono-layer integrity and antioxidant effects on the alveolar epithelial cells. A549 cells were exposed to MSE (0.1 to 5 μg/mL) or cannabinoid (+)-WIN 55,212-2 (WIN; 0.01 to 1 μM) for 24 h. Epithelial integrity and protein expression of claudin (Cl)-2, Cl-5, and occludin (Ocl) were evaluated by transepithelial electrical resistance (TEER), permeability assay, Western blot, immunofluorescence, and qPCR. TEER decreased after MSE or WIN exposure, whereas the monolayer permeability increased. Protein expression and localization of Cl-2 and Ocl were reduced after MSE treatment. However, WIN increased Cl-2 protein and decreased Cl-5 and Ocl. Differential gene expressions were observed between treatments. Malondialdehyde (MDA) production and advanced oxidation protein products (AOPP) determination showed that MSE increased AOPP, whereas WIN augmented the MDA production and decreased AOPP levels. The activity of antioxidant enzymes shows an increase in catalase, glutathione-S-transferase, γ-glutamyl transferase and arginase after MSE treatment and a decrease with WIN. Data indicates that MSE exposure alters epithelial integrity and the alveolar cells antioxidant response that, finally, may lead to lung damage.

Chronic exposure to a synthetic cannabinoid improves cognition and increases locomotor activity in Tg4-42 Alzheimer's disease mice

Background

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by cognitive decline and behavior impairments. Despite recent approvals of anti-amyloid antibodies, there remains a need for disease modifying and easily accessible therapies. Emerging evidence suggests that targeting the endocannabinoid system may hold promise for AD therapy as it plays a crucial role in different physiological processes, including learning, memory and anxiety, as well as inflammatory and immune responses.

Objective

In this study, we investigated the therapeutic potential of the synthetic cannabinoid WIN 55,212-2 on memory deficits in Tg4-42 transgenic mice.

Methods

Tg4-42 mice were assigned to two treatment groups to investigate the preventive effects of WIN 55,212-2 after a prolonged washout period, as well as the therapeutic effects of WIN 55,212-2 on behavior. Furthermore, the effects of WIN 55,212-2 treatment on AD pathology, including inflammation, amyloid-β load, neurogenesis, and brain glucose metabolism, were evaluated.

Results

Therapeutic WIN 55,212-2 treatment rescued recognition memory and spatial reference deficits in Tg4-42 mice. Furthermore, therapeutic WIN 55,212-2 administration improved motor performance. In addition, preventative WIN 55,212-2 treatment rescued spatial learning and reference memory deficits. Importantly, WIN 55,212-2 treatment did not affect anxiety-like behavior. However, therapeutic and preventative WIN 55,212-2 treatment resulted in an increase locomotor activity and swimming speed in Tg4-42 mice. WIN-treatment reduced microgliosis in the hippocampus of preventively treated mice and rescued brain glucose metabolism in therapeutically treated Tg4-42 mice.

Conclusions

Our findings emphasize the therapeutic promise of the synthetic cannabinoid WIN 55,212-2 in alleviating behavioral and cognitive deficits linked to AD.

The role of the endocannabinoid system in the pathogenesis and treatment of epilepsy

Epilepsy is a group of chronic neurological brain disorders characterized by recurrent spontaneous unprovoked seizures, which are accompanied by significant neurobiological, cognitive, and psychosocial impairments. With a global prevalence of approximately 0.5-1 % of the population, epilepsy remains a serious public health concern. Despite the development and widespread use of over 20 anticonvulsant drugs, around 30 % of patients continue to experience drug-resistant seizures, leading to a substantial reduction in quality of life and increased mortality risk. Given the limited efficacy of current treatments, exploring new therapeutic approaches is critically important. In recent years, Gi-protein-coupled receptors, particularly cannabinoid receptors CB1 and CB2, have garnered increasing attention as promising targets for the treatment seizures and prevention of epilepsy. Emerging evidence suggests a significant role of the cannabinoid system in modulating neuronal activity and protecting against hyperexcitability, underscoring the importance of further research in this area. This review provides up-to-date insights into the pathogenesis and treatment of epilepsy, with a special focus on the role of the cannabinoid system, highlighting the need for continued investigation to develop more effective therapeutic strategies.

Prenatal tetrahydrocannabinol and cannabidiol exposure produce sex-specific pathophysiological phenotypes in the adolescent prefrontal cortex and hippocampus

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.

The Development of Cannabinoids as Therapeutic Agents in the United States

Cannabis is one of the oldest and widely used substances in the world. Cannabinoids within the cannabis plant, known as phytocannabinoids, mediate cannabis' effects through interactions with the body's endogenous cannabinoid system. This endogenous system, the endocannabinoid system, has important roles in physical and mental health. These roles point to the potential to develop cannabinoids as therapeutic agents while underscoring the risks related to interfering with the endogenous system during nonmedical use. This scoping narrative review synthesizes the current evidence for both the therapeutic and adverse effects of the major (i.e., Δ9-tetrahydrocannabinol and cannabidiol) and lesser studied minor phytocannabinoids, from nonclinical to clinical research. We pay particular attention to the areas where evidence is well established, including analgesic effects after acute exposures and neurocognitive risks after acute and chronic use. In addition, drug development considerations for cannabinoids as therapeutic agents within the United States are reviewed. The proposed clinical study design considerations encourage methodological standards for greater scientific rigor and reproducibility to ultimately extend our knowledge of the risks and benefits of cannabinoids for patients and providers. SIGNIFICANCE STATEMENT: This work provides a review of prior research related to phytocannabinoids, including therapeutic potential and known risks in the context of drug development within the United States. We also provide study design considerations for future cannabinoid drug development.

The Sobering Sting: Oleoyl Serotonin Is a Novel Stephanoconus Snail Venom-Derived Antagonist of Cannabinoid Receptors That Counteracts Learning and Memory Deficits

Cannabinoid receptors (CB1 and CB2) are promising targets for a better understanding of neurological diseases. Nevertheless, only a few ligands of CB have reached clinical application so far. Venoms are considered as interesting sources of novel biologically active compounds. Here, we describe an endocannabinoid-like molecule, oleoyl serotonin (OS), present in the venom of Stephanoconus snails. Using electrophysiological assays, it was shown that OS inhibits CB1 and CB2. Structure-activity relationship studies using a chimeric CB1/2 revealed that the domain encompassing the transmembrane helix V (TMHV)- intracellular loop 3 (ICL3)-TMHVI of the CB2 is critical for the binding and function of OS. We concluded that OS binds to sites of the CB2 that are different from the binding sites of the non-selective CB agonist WIN55,212-2. Behavioral assays in mice showed that OS counteracted learning and memory deficits caused by WIN55,212-2. Furthermore, a selectivity screening of OS showed high selectivity for CB over various ion channels and receptors. Overall, OS may represent a new approach to the prevention and treatment of learning and memory cognition impairment in neurological diseases.

A GraphSAGE-based model with fingerprints only to predict drug-drug interactions

Drugs are an effective way to treat various diseases. Some diseases are so complicated that the effect of a single drug for such diseases is limited, which has led to the emergence of combination drug therapy. The use multiple drugs to treat these diseases can improve the drug efficacy, but it can also bring adverse effects. Thus, it is essential to determine drug-drug interactions (DDIs). Recently, deep learning algorithms have become popular to design DDI prediction models. However, most deep learning-based models need several types of drug properties, inducing the application problems for drugs without these properties. In this study, a new deep learning-based model was designed to predict DDIs. For wide applications, drugs were first represented by commonly used properties, referred to as fingerprint features. Then, these features were perfectly fused with the drug interaction network by a type of graph convolutional network method, GraphSAGE, yielding high-level drug features. The inner product was adopted to score the strength of drug pairs. The model was evaluated by 10-fold cross-validation, resulting in an AUROC of 0.9704 and AUPR of 0.9727. Such performance was better than the previous model which directly used drug fingerprint features and was competitive compared with some other previous models that used more drug properties. Furthermore, the ablation tests indicated the importance of the main parts of the model, and we analyzed the strengths and limitations of a model for drugs with different degrees in the network. This model identified some novel DDIs that may bring expected benefits, such as the combination of PEA and cannabinol that may produce better effects. DDIs that may cause unexpected side effects have also been discovered, such as the combined use of WIN 55,212-2 and cannabinol. These DDIs can provide novel insights for treating complex diseases or avoiding adverse drug events.

AsKC11, a Kunitz Peptide from Anemonia sulcata, Is a Novel Activator of G Protein-Coupled Inward-Rectifier Potassium Channels

(1) Background: G protein-coupled inward-rectifier potassium (GIRK) channels, especially neuronal GIRK1/2 channels, have been the focus of intense research interest for developing drugs against brain diseases. In this context, venom peptides that selectively activate GIRK channels can be seen as a new source for drug development. Here, we report on the identification and electrophysiological characterization of a novel activator of GIRK1/2 channels, AsKC11, found in the venom of the sea anemone Anemonia sulcata. (2) Methods: AsKC11 was purified from the sea anemone venom by reverse-phase chromatography and the sequence was identified by mass spectrometry. Using the two-electrode voltage-clamp technique, the activity of AsKC11 on GIRK1/2 channels was studied and its selectivity for other potassium channels was investigated. (3) Results: AsKC11, a Kunitz peptide found in the venom of A. sulcata, is the first peptide shown to directly activate neuronal GIRK1/2 channels independent from Gi/o protein activity, without affecting the inward-rectifier potassium channel (IRK1) and with only a minor effect on K_V1.6 channels. Thus, AsKC11 is a novel activator of GIRK channels resulting in larger K⁺ currents because of an increased chord conductance. (4) Conclusions: These discoveries provide new insights into a novel class of GIRK activators.