Protective Effects of Cannabidivarin and Cannabigerol on Cells of the Blood-Brain Barrier Under Ischemic Conditions

View details for Cannabis and Cannabinoid Research cover image“Preclinical studies have shown cannabidiol is protective in models of ischemic stroke. Based on results from our recent systematic review, we investigated the effects of two promising neuroprotective phytocannabinoids, cannabigerol (CBG) and cannabidivarin (CBDV), on cells of the blood-brain barrier (BBB), namely human brain microvascular endothelial cells (HBMECs), pericytes, and astrocytes.

Results: In astrocytes CBG and CBDV attenuated levels of interleukin-6 (IL-6) and lactate dehydrogenase (LDH), whereas CBDV (10 nM-10 μM) also decreased vascular endothelial growth factor (VEGF) secretion. CBDV (300 nM-10 μM) attenuated levels of monocyte chemoattractant protein (MCP)-1 in HBMECs. In astrocytes, CBG decreased levels of DNA damage proteins, including p53, whereas CBDV increased levels of DNA damage markers. Antagonists for CB1, CB2, PPAR-γ, PPAR-α, 5-HT1A, and TRPV1 had no effect on CBG (3 μM) or CBDV (1 μM)-mediated decreases in LDH in astrocytes. GPR55 and GPR18 were partially implicated in the effects of CBDV, but no molecular target was identified for CBG.

Conclusions: We show that CBG and CBDV were protective against OG mediated injury in three different cells that constitute the BBB, modulating different hallmarks of ischemic stroke pathophysiology. These data enhance our understanding of the protective effects of CBG and CBDV and warrant further investigation into these compounds in ischemic stroke. Future studies should identify other possible neuroprotective effects of CBG and CBDV and their corresponding mechanisms of action.”

https://pubmed.ncbi.nlm.nih.gov/33998890/

“This study provides novel data on the neuroprotective and anti-inflammatory properties of CBG and CBDV in an in vitro model of IR. These data, together with evidence from other studies, corroborate the protective properties of these compounds and further studies are needed to elucidate the mechanism of action of CBG and CBDV and whether they can modulate BBB permeability in more clinically relevant in vivo models of ischemic stroke. There is lack of effective treatments for ischemic stroke, a condition that will increase in prevalence in coming years, to which cannabinoids may offer a unique therapeutic strategy.” 

https://www.liebertpub.com/doi/10.1089/can.2020.0159

Cannabidiol in Neurological and Neoplastic Diseases: Latest Developments on the Molecular Mechanism of Action

ijms-logo“As the major nonpsychotropic constituent of Cannabis sativa, cannabidiol (CBD) is regarded as one of the most promising therapeutic agents due to its proven effectiveness in clinical trials for many human diseases. Due to the urgent need for more efficient pharmacological treatments for several chronic diseases, in this review, we discuss the potential beneficial effects of CBD for Alzheimer’s disease, epilepsy, multiple sclerosis, and neurological cancers. Due to its wide range of pharmacological activities (e.g., antioxidant, anti-inflammatory, and neuroprotective properties), CBD is considered a multimodal drug for the treatment of a range of neurodegenerative disorders, and various cancer types, including neoplasms of the neural system. The different mechanisms of action of CBD are here disclosed, together with recent progress in the use of this cannabis-derived constituent as a new therapeutic approach.”

https://pubmed.ncbi.nlm.nih.gov/33919010/

https://www.mdpi.com/1422-0067/22/9/4294

L-Theanine Prevents Long-Term Affective and Cognitive Side-Effects of Adolescent Δ-9-Tetrahydrocannabinol Exposure and Blocks Associated Molecular and Neuronal Abnormalities in the Mesocorticolimbic Circuitry

Journal of Neuroscience“Chronic adolescent exposure to Δ-9-Tetrahydrocannabinol (THC) is linked to elevated neuropsychiatric risk and induces neuronal, molecular and behavioural abnormalities resembling neuropsychiatric endophenotypes. Previous evidence has revealed that the mesocorticolimbic circuitry, including the prefrontal cortex (PFC) and mesolimbic dopamine (DA) pathway are particularly susceptible to THC-induced pathological alterations, including dysregulation of DAergic activity states, loss of PFC GABAergic inhibitory control and affective and cognitive abnormalities. There are currently limited pharmacological intervention strategies capable of preventing THC-induced neuropathological adaptations.

L-theanine is an amino acid analogue of L-glutamate and L-glutamine derived from various plant sources, including green tea leaves. L-theanine has previously been shown to modulate levels of GABA, DA and glutamate in various neural regions and to possess neuroprotective properties.

Using a pre-clinical model of adolescent THC exposure in male rats, we report that L-theanine pre-treatment prior to adolescent THC exposure is capable of preventing long-term, THC-induced dysregulation of both PFC and VTA DAergic activity states, a neuroprotective effect which persists into adulthood. In addition, pre-treatment with L-theanine blocked THC-induced downregulation of local GSK-3 and Akt signaling pathways directly in the PFC, two biomarkers previously associated with cannabis-related psychiatric risk and sub-cortical DAergic dysregulation.

Finally, L-theanine powerfully blocked the development of both affective and cognitive abnormalities commonly associated with adolescent THC exposure, further demonstrating functional and long-term neuroprotective effects of L-theanine in the mesocorticolimbic system.

SIGNIFICANCE STATEMENT With the increasing trend of cannabis legalization and consumption during adolescence, it is essential to expand knowledge on the potential effects of adolescent cannabis exposure on brain development and identify potential pharmacological strategies to minimize THC-induced neuropathology. Previous evidence demonstrates that adolescent THC exposure induces long-lasting affective and cognitive abnormalities, mesocorticolimbic dysregulation and schizophrenia-like molecular biomarkers that persist into adulthood.

We demonstrate for the first time that L-theanine, an amino acid analogue of L-glutamate and L-glutamine, is capable of preventing long-term THC side-effects. L-theanine prevented development of THC-induced behavioral aberrations, blocked cortical downregulation of local GSK-3 and Akt signaling pathways and normalized dysregulation of both PFC and VTA DAergic activity, demonstrating powerful and functional neuroprotective effects against THC-induced developmental neuropathology.”

https://pubmed.ncbi.nlm.nih.gov/33268546/

https://www.jneurosci.org/content/early/2020/11/24/JNEUROSCI.1050-20.2020

Natural Salicylates and Their Roles in Human Health

ijms-logo“Salicylic acid (SA) is a plant hormone which plays a crucial role in the plant defense against various pathogens and abiotic stresses. Increasing reports suggest that this phenolic compound and its derivatives, collectively termed salicylates, not only regulate plant defense but also have beneficial effects on human health. Both natural and synthetic salicylates are known to have multiple targets in humans, thereby exhibiting various appreciating pharmacological roles, including anti-inflammatory, anticancer, neuroprotective, antidiabetic effects, and so on. The role of some salicylates, such as acetylsalicylic acid (aspirin), 5-aminosalicylic acid (mesalazine), and amorfrutins in human diseases has been well studied in vitro. However, their clinical significance in different diseases is largely unknown. Based on recent studies, five natural salicylates, including amorfrutin, ginkgolic acid, grifolic acid, tetrahydrocannabinolic acid, and cannabidiolic acid, showed potential roles in different challenging human diseases. This review summarizes together some of the recent information on multitarget regulatory activities of these natural salicylates and their pharmacological roles in human health.”

https://pubmed.ncbi.nlm.nih.gov/33260759/

https://www.mdpi.com/1422-0067/21/23/9049

Use of Medical Cannabis to Treat Traumatic Brain Injury

View details for Journal of Neurotrauma cover image“There is not a single pharmacological agent with demonstrated therapeutic efficacy for traumatic brain injury (TBI). With recent legalization efforts and the growing popularity of medical cannabis, patients with TBI will inevitably consider medical cannabis as a treatment option.

Preclinical TBI research suggests cannabinoids have neuroprotective and psychotherapeutic properties.

Our review identified a paucity of high-quality studies examining the beneficial and adverse effects of medical cannabis on traumatic brain injury, with only a single Phase III randomized control trial. However, observational studies demonstrate that TBI patients are using medical and recreational cannabis to treat their symptoms, highlighting inconsistencies between public policy, perception of potential efficacy, and the dearth of empirical evidence.

We conclude that randomized controlled trials and prospective studies with appropriate control groups are necessary to fully understand the efficacy and potential adverse effects of medical cannabis for TBI.”

https://pubmed.ncbi.nlm.nih.gov/33256496/

https://www.liebertpub.com/doi/10.1089/neu.2020.7148

Emerging potential of cannabidiol in reversing proteinopathies

Ageing Research Reviews “The aberrant accumulation of disease-specific protein aggregates accompanying cognitive decline is a pathological hallmark of age-associated neurological disorders, also termed as proteinopathies, including Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis and multiple sclerosis.

Along with oxidative stress and neuroinflammation, disruption in protein homeostasis (proteostasis), a network that constitutes protein surveillance system, plays a pivotal role in the pathobiology of these dementia disorders.

Cannabidiol, a non-psychotropic phytocannabinoid of Cannabis sativa, is known for its pleiotropic neuropharmacological effects on the central nervous system, including the ability to abate oxidative stress, neuroinflammation, and protein misfolding. Over the past years, compelling evidence has documented disease-modifying role of cannabidiol in various preclinical and clinical models of neurological disorders, suggesting the potential therapeutic implications of cannabidiol in these disorders.

Because of its putative role in the proteostasis network in particular, cannabidiol could be a potent modulator for reversing not only age-associated neurodegeneration but also other protein misfolding disorders. However, the current understanding is insufficient to underpin this proposition. In this review, we discuss the potentiality of cannabidiol as a pharmacological modulator of the proteostasis network, highlighting its neuroprotective and aggregates clearing roles in the neurodegenerative disorders.

We anticipate that the current effort will advance our knowledge on the implication of CBD in proteostasis network, opening up a new therapeutic window for ageing proteinopathies.”

https://pubmed.ncbi.nlm.nih.gov/33181336/

“Cannabidiol reduces oxidative stress and neuroinflammation of brain.”

https://www.sciencedirect.com/science/article/pii/S1568163720303445?via%3Dihub

Molecular Targets of Cannabidiol in Experimental Models of Neurological Disease

molecules-logo“Cannabidiol (CBD) is a non-psychoactive phytocannabinoid known for its beneficial effects including antioxidant and anti-inflammatory properties. Moreover, CBD is a compound with antidepressant, anxiolytic, anticonvulsant and antipsychotic effects. Thanks to all these properties, the interest of the scientific community for it has grown.

Indeed, CBD is a great candidate for the management of neurological diseases. The purpose of our review is to summarize the in vitro and in vivo studies published in the last 15 years that describe the biochemical and molecular mechanisms underlying the effects of CBD and its therapeutic application in neurological diseases.

CBD exerts its neuroprotective effects through three G protein coupled-receptors (adenosine receptor subtype 2A, serotonin receptor subtype 1A and G protein-coupled receptor 55), one ligand-gated ion channel (transient receptor potential vanilloid channel-1) and one nuclear factor (peroxisome proliferator-activated receptor γ). Moreover, the therapeutical properties of CBD are also due to GABAergic modulation.

In conclusion, CBD, through multi-target mechanisms, represents a valid therapeutic tool for the management of epilepsy, Alzheimer’s disease, multiple sclerosis and Parkinson’s disease.”

https://pubmed.ncbi.nlm.nih.gov/33171772/

https://www.mdpi.com/1420-3049/25/21/5186

The impact of cannabinoid type 2 receptors (CB2Rs) in neuroprotection against neurological disorders

 Acta Pharmacologica Sinica“Cannabinoids have long been used for their psychotropic and possible medical properties of symptom relief. In the past few years, a vast literature shows that cannabinoids are neuroprotective under different pathological situations.

Most of the effects of cannabinoids are mediated by the well-characterized cannabinoid receptors, the cannabinoid type 1 receptor (CB1R) and cannabinoid type 2 receptor (CB2R). Even though CB1Rs are highly expressed in the central nervous system (CNS), the adverse central side effects and the development of tolerance resulting from CB1R activation may ultimately limit the clinical utility of CB1R agonists. In contrast to the ubiquitous presence of CB1Rs, CB2Rs are less commonly expressed in the healthy CNS but highly upregulated in glial cells under neuropathological conditions.

Experimental studies have provided robust evidence that CB2Rs seem to be involved in the modulation of different neurological disorders. In this paper, we summarize the current knowledge regarding the protective effects of CB2R activation against the development of neurological diseases and provide a perspective on the future of this field. A better understanding of the fundamental pharmacology of CB2R activation is essential for the development of clinical applications and the design of novel therapeutic strategies.”

https://pubmed.ncbi.nlm.nih.gov/33024239/

https://www.nature.com/articles/s41401-020-00530-2

A Cannabinoid Type 2 (CB2) Receptor Agonist Augments NOS-Dependent Responses of Cerebral Arterioles during Type 1 Diabetes

Microvascular Research “While activation of cannabinoid (CB2) receptors has been shown to be neuroprotective, no studies have examined whether this neuroprotection is directed at cerebral arterioles and no studies have examined whether activation of CB2 receptors can rescue cerebrovascular dysfunction during a chronic disease state such as type 1 diabetes (T1D).

Our goal was to test the hypothesis that administration of a CB2 agonist (JWH-133) would improve impaired endothelial (eNOS)- and neuronal (nNOS)- dependent dilation of cerebral arterioles during T1D.

In vivo diameter of cerebral arterioles in nondiabetic and T1D rats was measured in response to an eNOS-dependent agonist (adenosine 5′-diphosphate; ADP), an nNOS-dependent agonist (N-methyl-D-aspartate; NMDA), and an NOS-independent agonist (nitroglycerin) before and 1 hour following JWH-133 (1 mg/kg IP). Dilation of cerebral arterioles to ADP and NMDA was greater in nondiabetic than in T1D rats.

Treatment with JWH-133 increased responses of cerebral arterioles to ADP and NMDA in both nondiabetic and T1D rats. Responses of cerebral arterioles to nitroglycerin were similar between nondiabetic and T1D rats, and JWH-133 did not influence responses to nitroglycerin in either group. The restoration in responses to the agonists by JWH-133 could be inhibited by treatment with a specific inhibitor of CB2 receptors (AM-630; 3 mg/kg IP).

Thus, activation of CB2 receptors can potentiate reactivity of cerebral arterioles during physiologic and pathophysiologic states. We speculate that treatment with CB2 receptor agonists may have potential therapeutic benefits for the treatment of cerebral vascular diseases via a mechanism that can increase cerebral blood flow.”

https://pubmed.ncbi.nlm.nih.gov/32979391/

“Activation of CB2 receptors improves cerebral vascular function. Activation of CB2 receptors improves responses in type 1 diabetes. We speculate that treatment with CB2 receptor agonists may have potential therapeutic benefits for the treatment of cerebral vascular disease that can contribute to the pathogenesis of stroke.”

https://www.sciencedirect.com/science/article/pii/S0026286220301370?via%3Dihub

Investigating the cumulative effects of Δ9-tetrahydrocannabinol and repetitive mild traumatic brain injury on adolescent rats

 Issue Cover“The prevalence of mild traumatic brain injury is highest amongst the adolescent population and can lead to complications including neuroinflammation and excitotoxicity.

Δ9-Tetrahydrocannabinol, the main psychoactive component of cannabis, is known to have anti-inflammatory properties and serves as a neuroprotective agent against excitotoxicity.

Thus, we investigated the effects of Δ9-tetrahydrocannabinol on recovery when administered either prior to or following repeated mild brain injuries.

We hypothesized that, in both experiments, Δ9-tetrahydrocannabinol administration would provide neuroprotection against mild injury outcomes and confer therapeutic benefit.

Δ9-Tetrahydrocannabinol administration following repeated mild traumatic brain injury was beneficial to three of the six behavioural outcomes affected by injury (reducing anxiety and depressive-like behaviours while also mitigating injury-induced deficits in short-term working memory). Δ9-Tetrahydrocannabinol administration following injury also showed beneficial effects on the expression of Cnr1Comt and Vegf-2R in the hippocampus, nucleus accumbens and prefrontal cortex.

There were no notable benefits of Δ9-tetrahydrocannabinol when administered prior to injury, suggesting that Δ9-tetrahydrocannabinol may have potential therapeutic benefit on post-concussive symptomology when administered post-injury, but not pre-injury.”

https://pubmed.ncbi.nlm.nih.gov/32954298/

 “Overall, this study suggests that THC has potential therapeutic efficacy for the treatment of RmTBI-induced symptomology but requires additional examination.”

https://academic.oup.com/braincomms/article/2/1/fcaa042/5819138