Direct modulation of the outer mitochondrial membrane channel, voltage-dependent anion channel 1 (VDAC1) by cannabidiol: a novel mechanism for cannabinoid-induced cell death

TRPV1 channel in the pathophysiology of epilepsy and its potential as a molecular target for the development of new antiseizure drug candidates

Identification of transient receptor potential cation channel, subfamily V member 1 (TRPV1), also known as capsaicin receptor, in 1997 was a milestone achievement in the research on temperature sensation and pain signalling. Very soon after it became evident that TRPV1 is implicated in a wide array of physiological processes in different peripheral tissues, as well as in the central nervous system, and thereby could be involved in the pathophysiology of numerous diseases. Increasing evidence suggests that modulation of TRPV1 may also affect seizure susceptibility and epilepsy. This channel is localized in brain regions associated with seizures and epilepsy, and its overexpression was found both in animal models of seizures and in brain samples from epileptic patients. Moreover, modulation of TRPV1 on non-neuronal cells (microglia, astrocytes, and/or peripheral immune cells) may have an impact on the neuroinflammatory processes that play a role in epilepsy and epileptogenesis. In this paper, we provide a comprehensive and critical overview of currently available data on TRPV1 as a possible molecular target for epilepsy management, trying to identify research gaps and future directions. Overall, several converging lines of evidence implicate TRPV1 channel as a potentially attractive target in epilepsy research but more studies are needed to exploit the possible role of TRPV1 in seizures/epilepsy and to evaluate the value of TRPV1 ligands as candidates for new antiseizure drugs.

Integrated omics of Saccharomyces cerevisiae CENPK2-1C reveals pleiotropic drug resistance and lipidomic adaptations to cannabidiol

Yeast metabolism can be engineered to produce xenobiotic compounds, such as cannabinoids, the principal isoprenoids of the plant Cannabis sativa, through heterologous metabolic pathways. However, yeast cell factories continue to have low cannabinoid production. This study employed an integrated omics approach to investigate the physiological effects of cannabidiol on S. cerevisiae CENPK2-1C yeast cultures. We treated the experimental group with 0.5 mM CBD and monitored CENPK2-1C cultures. We observed a latent-stationary phase post-diauxic shift in the experimental group and harvested samples in the inflection point of this growth phase for transcriptomic and metabolomic analysis. We compared the transcriptomes of the CBD-treated yeast and the positive control, identifying eight significantly overexpressed genes with a log fold change of at least 1.5 and a significant adjusted p-value. Three notable genes were PDR5 (an ABC-steroid and cation transporter), CIS1, and YGR035C. These genes are all regulated by pleiotropic drug resistance linked promoters. Knockout and rescue of PDR5 showed that it is a causal factor in the post-diauxic shift phenotype. Metabolomic analysis revealed 48 significant spectra associated with CBD-fed cell pellets, 20 of which were identifiable as non-CBD compounds, including fatty acids, glycerophospholipids, and phosphate-salvage indicators. Our results suggest that mitochondrial regulation and lipidomic remodeling play a role in yeast's response to CBD, which are employed in tandem with pleiotropic drug resistance (PDR). We conclude that bioengineers should account for off-target product C-flux, energy use from ABC-transport, and post-stationary phase cell growth when developing cannabinoid-biosynthetic yeast strains.

Advances and Challenges in Modeling Cannabidiol Pharmacokinetics and Hepatotoxicity

Cannabidiol (CBD) is a pharmacologically active metabolite of cannabis that is US Food and Drug Administration approved to treat seizures associated with Lennox-Gastaut syndrome, Dravet syndrome, and tuberous sclerosis complex in children aged 1 year and older. During clinical trials, CBD caused dose-dependent hepatocellular toxicity at therapeutic doses. The risk for toxicity was increased in patients taking valproate, another hepatotoxic antiepileptic drug, through an unknown mechanism. With the growing popularity of CBD in the consumer market, an improved understanding of the safety risks associated with CBD is needed to ensure public health. This review details current efforts to describe CBD pharmacokinetics and mechanisms of hepatotoxicity using both pharmacokinetic models and in vitro models of the liver. In addition, current evidence and knowledge gaps related to intracellular mechanisms of CBD-induced hepatotoxicity are described. The authors propose future directions that combine systems-based models with markers of CBD-induced hepatotoxicity to understand how CBD pharmacokinetics may influence the adverse effect profile and risk of liver injury for those taking CBD. SIGNIFICANCE STATEMENT: This review describes current pharmacokinetic modeling approaches to capture the metabolic clearance and safety profile of cannabidiol (CBD). CBD is an increasingly popular natural product and US Food and Drug Administration-approved antiepileptic drug known to cause clinically significant enzyme-mediated drug interactions and hepatotoxicity at therapeutic doses. CBD metabolism, pharmacokinetics, and putative mechanisms of CBD-induced liver injury are summarized from available preclinical data to inform future modeling efforts for understanding CBD toxicity.

Effects of Cannabidiol, ∆9-Tetrahydrocannabinol, and WIN 55-212-22 on the Viability of Canine and Human Non-Hodgkin Lymphoma Cell Lines

In our previous study, we demonstrated the impact of overexpression of CB1 and CB2 cannabinoid receptors and the inhibitory effect of endocannabinoids (2-arachidonoylglycerol (2-AG) and Anandamide (AEA)) on canine (Canis lupus familiaris) and human (Homo sapiens) non-Hodgkin lymphoma (NHL) cell lines' viability compared to cells treated with a vehicle. The purpose of this study was to demonstrate the anti-cancer effects of the phytocannabinoids, cannabidiol (CBD) and ∆9-tetrahydrocannabinol (THC), and the synthetic cannabinoid WIN 55-212-22 (WIN) in canine and human lymphoma cell lines and to compare their inhibitory effect to that of endocannabinoids. We used malignant canine B-cell lymphoma (BCL) (1771 and CLB-L1) and T-cell lymphoma (TCL) (CL-1) cell lines, and human BCL cell line (RAMOS). Our cell viability assay results demonstrated, compared to the controls, a biphasic effect (concentration range from 0.5 μM to 50 μM) with a significant reduction in cancer viability for both phytocannabinoids and the synthetic cannabinoid. However, the decrease in cell viability in the TCL CL-1 line was limited to CBD. The results of the biochemical analysis using the 1771 BCL cell line revealed a significant increase in markers of oxidative stress, inflammation, and apoptosis, and a decrease in markers of mitochondrial function in cells treated with the exogenous cannabinoids compared to the control. Based on the IC50 values, CBD was the most potent phytocannabinoid in reducing lymphoma cell viability in 1771, Ramos, and CL-1. Previously, we demonstrated the endocannabinoid AEA to be more potent than 2-AG. Our study suggests that future studies should use CBD and AEA for further cannabinoid testing as they might reduce tumor burden in malignant NHL of canines and humans.

Cannabidiol Disrupts Mitochondrial Respiration and Metabolism and Dysregulates Trophoblast Cell Differentiation

Trophoblast differentiation is a crucial process in the formation of the placenta where cytotrophoblasts (CTs) differentiate and fuse to form the syncytiotrophoblast (ST). The bioactive components of cannabis, such as Δ9-THC, are known to disrupt trophoblast differentiation and fusion, as well as mitochondrial dynamics and respiration. However, less is known about the impact of cannabidiol (CBD) on trophoblast differentiation. Due to the central role of mitochondria in stem cell differentiation, we evaluated the impact of CBD on trophoblast mitochondrial function and differentiation. Using BeWo b30 cells, we observed decreased levels of mRNA for markers of syncytialization (GCM1, ERVW1, hCG) following 20 µM CBD treatment during differentiation. In CTs, CBD elevated transcript levels for the mitochondrial and cellular stress markers HSP60 and HSP70, respectively. Furthermore, CBD treatment also increased the lipid peroxidation and oxidative damage marker 4-hydroxynonenal. Mitochondrial membrane potential, basal respiration and ATP production were diminished with the 20 µM CBD treatment in both sub-lineages. mRNA levels for endocannabinoid system (ECS) components (FAAH, NAPEPLD, TRPV1, CB1, CB2, PPARγ) were altered differentially by CBD in CTs and STs. Overall, we demonstrate that CBD impairs trophoblast differentiation and fusion, as well as mitochondrial bioenergetics and redox homeostasis.

An Overview of Cannabidiol

Cannabidiol (CBD) is one of the most interesting constituents of cannabis, garnering significant attention in the medical community in recent years due to its proven benefit for reducing refractory seizures in pediatric patients. Recent legislative changes in the United States have made CBD readily available to the general public, with up to 14% of adults in the United States having tried it in 2019. CBD is used to manage a myriad of symptoms, including anxiety, pain, and sleep disturbances, although rigorous evidence for these indications is lacking. A significant advantage of CBD over the other more well-known cannabinoid delta-9-tetrahydroncannabinol (THC) is that CBD does not produce a "high." As patients increasingly self-report its use to manage their medical conditions, and as the opioid epidemic continues to drive the quest for alternative pain management approaches, the aims of this narrative review are to provide a broad overview of the discovery, pharmacology, and molecular targets of CBD, its purported and approved neurologic indications, evidence for its analgesic potential, regulatory implications for patients and providers, and future research needs.

Combining nano-differential scanning fluorimetry and microscale thermophoresis to investigate VDAC1 interaction with small molecules

The mitochondrial voltage-dependent anion channel 1 (VDAC1) plays a central role in metabolism and apoptosis, which makes it a promising therapeutic target. Nevertheless, molecular mechanisms governing VDAC1 functioning remain unclear. Small-molecule ligands specifically interacting with the channel provide an attractive way of exploring its structure-function relationships and can possibly be used as founding stones for future drug-candidates. While around 30 VDAC1 ligands have been identified over the years, various techniques have been used by research teams, making a fair and direct comparison between compounds impossible. To tackle this issue, we performed ligand-binding assays on a representative set of seventeen known VDAC1 ligands using nano-differential scanning fluorimetry and microscale thermophoresis. While all the compounds have been confirmed as VDAC1 ligands by at least one method, combining both technologies lead to the selection of four molecules (cannabidiol, curcumin, DIDS and VBIT4) as chemical starting points for future design of VDAC1 selective ligands.

Microglial voltage-dependent anion channel 1 signaling modulates sleep deprivation-induced transition to chronic postsurgical pain

STUDY OBJECTIVES

This study verified that sleep deprivation before and after skin/muscle incision and retraction (SMIR) surgery increased the risk of chronic pain and investigated the underlying roles of microglial voltage-dependent anion channel 1 (VDAC1) signaling.

METHODS

Adult mice received 6 hours of total sleep deprivation from 1 day prior to SMIR until the third day after surgery. Mechanical and heat-evoked pain was assessed before and within 21 days after surgery. Microglial activation and changes in VDAC1 expression and oligomerization were measured. Minocycline was injected to observe the effects of inhibiting microglial activation on pain maintenance. The VDAC1 inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) and oligomerization inhibitor VBIT-4 were used to determine the roles of VDAC1 signaling on microglial adenosine 5' triphosphate (ATP) release, inflammation (IL-1β and CCL2), and chronicity of pain.

RESULTS

Sleep deprivation significantly increased the pain duration after SMIR surgery, activated microglia, and enhanced VDAC1 signaling in the spinal cord. Minocycline inhibited microglial activation and alleviated sleep deprivation-induced pain maintenance. Lipopolysaccharide (LPS)-induced microglial activation was accompanied by increased VDAC1 expression and oligomerization, and more VDAC1 was observed on the cell membrane surface compared with control. DIDS and VBIT-4 rescued LPS-induced microglial ATP release and IL-1β and CCL2 expression. DIDS and VBIT-4 reversed sleep loss-induced microglial activation and pain chronicity in mice, similar to the effects of minocycline. No synergistic effects were found for minocycline plus VBIT-4 or DIDS.

CONCLUSIONS

Perioperative sleep deprivation activated spinal microglia and increases the risk of chronic postsurgical pain in mice. VDAC1 signaling regulates microglial activation-related ATP release, inflammation, and chronicity of pain.

Proteome-Wide Profiling Using Sample Multiplexing of a Human Cell Line Treated with Cannabidiol (CBD) and Tetrahydrocannabinol (THC)

Cannabis has been used historically for both medicinal and recreational purposes, with the most notable cannabinoids being cannabidiol (CBD) and tetrahydrocannabinol (THC). Although their therapeutic effects have been well studied and their recreational use is highly debated, the underlying mechanisms of their biological effects remain poorly defined. In this study, we use isobaric tag-based sample multiplexed proteome profiling to investigate protein abundance differences in the human neuroblastoma SH-SY5Y cell line treated with CBD and THC. We identified significantly regulated proteins by each treatment and performed a pathway classification and associated protein-protein interaction analysis. Our findings suggest that these treatments may lead to mitochondrial dysfunction and induce endoplasmic reticulum stress. These data can potentially be interrogated further to investigate the potential role of CBD and THC in various biological and disease contexts, providing a foundation for future studies.

Neutralization of Cannabidiol Neurotoxicity in Neuron-Astrocyte Sandwich Coculture

Cannabidiol (CBD), a main nonpsychoactive phytocannabinoid in the Cannabis genus, has been in the limelight for its potential health benefits in various neurological diseases. However, the safety issue of CBD in the nervous system has not been settled fully, while CBD has been reported to have mild side effects including dizziness and somnolence. In this work, a platform of neuron-astrocyte sandwich coculture to investigate the neurotoxicity of CBD, as well as the neuronal responses to CBD, in a more in vivo relevant mode is constructed. CBD (15 and 30 µm) causes the viability decrease, along with morphological damage, in the neuron-alone culture, whereas its neurotoxic effects are significantly attenuated by the supports of astrocytes in the neuron-astrocyte coculture. In addition, it is found that CBD-induced increase of intracellular Ca2+ concentration and depolarization of mitochondrial membrane potential, via activation of transient receptor potential vanilloid 1, are noticeably ameliorated by coculturing neurons with astrocytes. This work provides crucial information in the development of CBD as therapeutics for neurological disorders, as well as in a fundamental understanding of how CBD works in the nervous system.

Cannabidiol Analogue for the Treatment of Morphine-Induced Addiction by Targeting PKM2

Opioid addiction is a chronically relapsing disorder that causes critical public health problems. Currently, there is a lack of effective drug treatment. Herein, one cannabidiol derivative, CIAC001, was discovered as an effective agent for treating morphine-induced addiction. In vitro, CIAC001 exhibited significantly improved anti-neuroinflammatory activity with lower toxicity. In vivo, CIAC001 ameliorated the morphine-induced withdrawal reaction, behavioral sensitization, and conditional position preference by inhibiting morphine-induced microglia activation and neuroinflammation. Target fishing for CIAC001 by activity-based protein profiling led to the identification of pyruvate kinase M2 (PKM2) as the target protein. CIAC001 bound to the protein-protein interface of the PKM2 dimer and promoted the tetramerization of PKM2. Moreover, CIAC001 exhibited an anti-neuroinflammatory effect by reversing the decrease of the PKM2 tetramer and inhibiting the nuclear translocation of PKM2. In summary, this study identified CIAC001 as a lead compound in targeting PKM2 to treat morphine-induced addiction.

Informing the Cannabis Conjecture: From Life's Beginnings to Mitochondria, Membranes and the Electrome-A Review

Before the late 1980s, ideas around how the lipophilic phytocannabinoids might be working involved membranes and bioenergetics as these disciplines were "in vogue". However, as interest in genetics and pharmacology grew, interest in mitochondria (and membranes) waned. The discovery of the cognate receptor for tetrahydrocannabinol (THC) led to the classification of the endocannabinoid system (ECS) and the conjecture that phytocannabinoids might be "working" through this system. However, the how and the "why" they might be beneficial, especially for compounds like CBD, remains unclear. Given the centrality of membranes and mitochondria in complex organisms, and their evolutionary heritage from the beginnings of life, revisiting phytocannabinoid action in this light could be enlightening. For example, life can be described as a self-organising and replicating far from equilibrium dissipating system, which is defined by the movement of charge across a membrane. Hence the building evidence, at least in animals, that THC and CBD modulate mitochondrial function could be highly informative. In this paper, we offer a unique perspective to the question, why and how do compounds like CBD potentially work as medicines in so many different conditions? The answer, we suggest, is that they can modulate membrane fluidity in a number of ways and thus dissipation and engender homeostasis, particularly under stress. To understand this, we need to embrace origins of life theories, the role of mitochondria in plants and explanations of disease and ageing from an adaptive thermodynamic perspective, as well as quantum mechanics.

Cannabidiol for Oral Health: A New Promising Therapeutical Tool in Dentistry

The medical use of cannabis has a very long history. Although many substances called cannabinoids are present in cannabis, Δ9tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD) and cannabinol (CBN) are the three main cannabinoids that are most present and described. CBD itself is not responsible for the psychotropic effects of cannabis, since it does not produce the typical behavioral effects associated with the consumption of this drug. CBD has recently gained growing attention in modern society and seems to be increasingly explored in dentistry. Several subjective findings suggest some therapeutic effects of CBD that are strongly supported by research evidence. However, there is a plethora of data regarding CBD's mechanism of action and therapeutic potential, which are in many cases contradictory. We will first provide an overview of the scientific evidence on the molecular mechanism of CBD's action. Furthermore, we will map the recent developments regarding the possible oral benefits of CBD. In summary, we will highlight CBD's promising biological features for its application in dentistry, despite exiting patents that suggest the current compositions for oral care as the main interest of the industry.

Cannabidiol modulates excitatory-inhibitory ratio to counter hippocampal hyperactivity

Cannabidiol (CBD), a non-euphoric component of cannabis, reduces seizures in multiple forms of pediatric epilepsies, but the mechanism(s) of anti-seizure action remain unclear. In one leading model, CBD acts at glutamatergic axon terminals, blocking the pro-excitatory actions of an endogenous membrane phospholipid, lysophosphatidylinositol (LPI), at the G-protein-coupled receptor GPR55. However, the impact of LPI-GPR55 signaling at inhibitory synapses and in epileptogenesis remains underexplored. We found that LPI transiently increased hippocampal CA3-CA1 excitatory presynaptic release probability and evoked synaptic strength in WT mice, while attenuating inhibitory postsynaptic strength by decreasing GABAARγ2 and gephyrin puncta. LPI effects at excitatory and inhibitory synapses were eliminated by CBD pre-treatment and absent after GPR55 deletion. Acute pentylenetrazole-induced seizures elevated GPR55 and LPI levels, and chronic lithium-pilocarpine-induced epileptogenesis potentiated LPI's pro-excitatory effects. We propose that CBD exerts potential anti-seizure effects by blocking LPI's synaptic effects and dampening hyperexcitability.

The Polypharmacological Effects of Cannabidiol

Cannabidiol (CBD) is a major phytocannabinoid present in Cannabis sativa (Linneo, 1753). This naturally occurring secondary metabolite does not induce intoxication or exhibit the characteristic profile of drugs of abuse from cannabis like Δ9-tetrahydrocannabinol (∆9-THC) does. In contrast to ∆9-THC, our knowledge of the neuro-molecular mechanisms of CBD is limited, and its pharmacology, which appears to be complex, has not yet been fully elucidated. The study of the pharmacological effects of CBD has grown exponentially in recent years, making it necessary to generate frequently updated reports on this important metabolite. In this article, a rationalized integration of the mechanisms of action of CBD on molecular targets and pharmacological implications in animal models and human diseases, such as epilepsy, pain, neuropsychiatric disorders, Alzheimer's disease, and inflammatory diseases, are presented. We identify around 56 different molecular targets for CBD, including enzymes and ion channels/metabotropic receptors involved in neurologic conditions. Herein, we compiled the knowledge found in the scientific literature on the multiple mechanisms of actions of CBD. The in vitro and in vivo findings are essential for fully understanding the polypharmacological nature of this natural product.

Cannabidiol alters mitochondrial bioenergetics via VDAC1 and triggers cell death in hormone-refractory prostate cancer

In spite of the huge advancements in both diagnosis and interventions, hormone refractory prostate cancer (HRPC) remains a major hurdle in prostate cancer (PCa). Metabolic reprogramming plays a key role in PCa oncogenesis and resistance. However, the dynamics between metabolism and oncogenesis are not fully understood. Here, we demonstrate that two multi-target natural products, cannabidiol (CBD) and cannabigerol (CBG), suppress HRPC development in the TRansgenic Adenocarcinoma of the Mouse Prostate (TRAMP) model by reprogramming metabolic and oncogenic signaling. Mechanistically, CBD increases glycolytic capacity and inhibits oxidative phosphorylation in enzalutamide-resistant HRPC cells. This action of CBD originates from its effect on metabolic plasticity via modulation of VDAC1 and hexokinase II (HKII) coupling on the outer mitochondrial membrane, which leads to strong shifts of mitochondrial functions and oncogenic signaling pathways. The effect of CBG on enzalutamide-resistant HRPC cells was less pronounced than CBD and only partially attributable to its action on mitochondria. However, when optimally combined, these two cannabinoids exhibited strong anti-tumor effects in TRAMP mice, even when these had become refractory to enzalutamide, thus pointing to their therapeutical potential against PCa.

Cannabidiol, a Regulator of Intracellular Calcium and Calpain

Cannabidiol (CBD) is one of the most abundant components of Cannabis and has long been used in Cannabis-based preparations. Recently, CBD has become a promising pharmacological agent because of its beneficial properties in the pathophysiology of several diseases. Although CBD is a kind of cannabinoid and acts on cannabinoid receptors (CB1 and CB2), molecular targets involved in diverse therapeutic properties of CBD have not been identified because CBD also interacts with other molecular targets. Considering that CBD alters the intracellular calcium level by which calpain activity is controlled, and both CBD and calpain are associated with various diseases related to calcium signaling, including neurological disorders, this review provides an overview of calpain and calcium signaling as possible molecular targets of CBD. As calpain is known to play an important role in the pathophysiology of neurological disease, a deeper understanding of its relationship with CBD will be meaningful. To understand the role of CBD as a calpain regulator, in silico structural analysis on the binding mode of CBD with calpain was performed.

THC and CBD: Similarities and differences between siblings

Δ9-tetrahydrocannabinol (THC) and its sibling, cannabidiol (CBD), are produced by the same Cannabis plant and have similar chemical structures but differ dramatically in their mechanisms of action and effects on brain functions. Both THC and CBD exhibit promising therapeutic properties; however, impairments and increased incidence of mental health diseases are associated with acute and chronic THC use, respectively, and significant side effects are associated with chronic use of high-dose CBD. This review covers recent molecular and preclinical discoveries concerning the distinct mechanisms of action and bioactivities of THC and CBD and their impact on human behavior and diseases. These discoveries provide a foundation for the development of cannabinoid-based therapeutics for multiple devastating diseases and to assure their safe use in the growing legal market of Cannabis-based products.

Beyond Pain Relief: A Review on Cannabidiol Potential in Medical Therapies

The phytocannabinoid cannabidiol (CBD) is receiving increasing attention due to its pharmacological properties. Although CBD is extracted from Cannabis sativa, it lacks the psychoactive effects of Δ9-tetrahydrocannabinol (THC) and has become an attractive compound for pharmacological uses due to its anti-inflammatory, antioxidant, anticonvulsant, and anxiolytic potential. The molecular mechanisms involved in CBD's biological effects are not limited to its interaction with classical cannabinoid receptors, exerting anti-inflammatory or pain-relief effects. Several pieces of evidence demonstrate that CBD interacts with other receptors and cellular signaling cascades, which further support CBD's therapeutic potential beyond pain management. In this review, we take a closer look at the molecular mechanisms of CBD and its potential therapeutic application in the context of cancer, neurodegeneration, and autoimmune diseases.

Inhibition of VDAC1 prevents oxidative stress and apoptosis induced by bisphenol A in spermatogonia via AMPK/mTOR signaling pathway

Bisphenol A (BPA), one of the main components of industrial products, is clinically associated with the increased male infertility rate. However, the underlying molecular mechanism of the BPA-resulted reproductive toxicity is not fully elucidated. Voltage-dependent anion channel 1 (VDAC1) is a pore protein and located at the outer mitochondrial membrane. As a mitochondrial gatekeeper, VDAC1 controls the release of reactive oxygen species (ROS) and the metabolic and energetic functions of mitochondria, and serves as a critical player in mitochondrial-mediated apoptosis. Herein, we explored the role of VDAC1 in BPA-induced apoptosis of spermatogonia. The results showed that BPA increased spermatogonia cell line GC-1 spg cell apoptosis and intracellular ROS level, and suppressed AMPK/mTOR signaling pathway at a dose of 80 μM for 48 hr. Lentivirus-mediated short hairpin RNA targeting VDAC1 (Lv-shVDAC1) silenced VDAC1 expression and enhanced BPA-restricted cell viability. Knockdown of VDAC1 inhibited the apoptosis of BPA-treated GC-1 spg cells determined by with changes of the expressions of pro-apoptotic and anti-apoptotic proteins. Knockdown of VDAC1 also alleviated the BPA-triggered intracellular ROS generation and oxidative stress. Moreover, silence of VDAC1 increased AMPKα1/2 phosphorylation and suppressed mTOR phosphorylation under BPA exposure. Dorsomorphin, an AMPK inhibitor, partially abolished the effects of VDAC1 gene silencing on BPA-stimulated GC-1 spg cells. In conclusion, inhibition of VDAC1 attenuated the BPA-induced oxidative stress and apoptosis and promoted the cell viability in spermatogonia through modulating AMPK/mTOR signaling pathway.

Cannabinoid-mediated targeting of mitochondria on the modulation of mitochondrial function and dynamics

Mitochondria play a critical role in the regulation of several biological processes (e.g., programmed cell death, inflammation, neurotransmission, cell differentiation). In recent years, accumulating findings have evidenced that cannabinoids, a group of endogenous and exogenous (synthetic and plant-derived) psychoactive compounds that bind to cannabinoid receptors, may modulate mitochondrial function and dynamics. As such, mitochondria have gained increasing interest as central mediators in cannabinoids' pharmacological and toxicological signatures. Here, we review the mechanisms underlying the cannabinoids' modulation of mitochondrial activity and dynamics, as well as the potential implications of such mitochondrial processes' disruption on cell homeostasis and disease. Interestingly, cannabinoids may target different mitochondrial processes (e.g., regulation of intracellular calcium levels, bioenergetic metabolism, apoptosis, and mitochondrial dynamics, including mitochondrial fission and fusion, transport, mitophagy, and biogenesis), by modulating multiple and complex signaling pathways. Of note, the outcome may depend on the experimental models used, as well as the chemical structure, concentration, and exposure settings to the cannabinoid, originating equivocal data. Notably, this interaction seems to represent not only an important feature of cannabinoids' toxicological signatures, with potential implications for the onset of distinct pathological conditions (e.g., cancer, neurodegenerative diseases, metabolic syndromes), but also an opportunity to develop novel therapeutic strategies for such pathologies, which is also discussed in this review.

Advances and Challenges of Cannabidiol as an Anti-Seizure Strategy: Preclinical Evidence

The use of Cannabis for medicinal purposes has been documented since ancient times, where one of its principal cannabinoids extracted from Cannabis sativa, cannabidiol (CBD), has emerged over the last few years as a promising molecule with anti-seizure potential. Here, we present an overview of recent literature pointing out CBD's pharmacological profile (solubility, metabolism, drug-drug interactions, etc.,), CBD's interactions with multiple molecular targets as well as advances in preclinical research concerning its anti-seizure effect on both acute seizure models and chronic models of epilepsy. We also highlight the recent attention that has been given to other natural cannabinoids and to synthetic derivatives of CBD as possible compounds with therapeutic anti-seizure potential. All the scientific research reviewed here encourages to continue to investigate the probable therapeutic efficacy of CBD and its related compounds not only in epilepsy but also and specially in drug-resistant epilepsy, since there is a dire need for new and effective drugs to treat this disease.

Effects of Cannabidiol on Exercise Physiology and Bioenergetics: A Randomised Controlled Pilot Trial

Background

Cannabidiol (CBD) has demonstrated anti-inflammatory, analgesic, anxiolytic and neuroprotective effects that have the potential to benefit athletes. This pilot study investigated the effects of acute, oral CBD treatment on physiological and psychological responses to aerobic exercise to determine its practical utility within the sporting context.

Methods

On two occasions, nine endurance-trained males (mean ± SD V̇O_2max: 57.4 ± 4.0 mL·min⁻¹·kg⁻¹) ran for 60 min at a fixed intensity (70% V̇O_2max) (RUN 1) before completing an incremental run to exhaustion (RUN 2). Participants received CBD (300 mg; oral) or placebo 1.5 h before exercise in a randomised, double-blind design. Respiratory gases (V̇O₂), respiratory exchange ratio (RER), heart rate (HR), blood glucose (BG) and lactate (BL) concentrations, and ratings of perceived exertion (RPE) and pleasure–displeasure were measured at three timepoints (T1–3) during RUN 1. V̇O_2max, RER_max, HR_max and time to exhaustion (TTE) were recorded during RUN 2. Venous blood was drawn at Baseline, Pre- and Post-RUN 1, Post-RUN 2 and 1 h Post-RUN 2. Data were synthesised using Cohen’s d_z effect sizes and 85% confidence intervals (CIs). Effects were considered worthy of further investigation if the 85% CI included ± 0.5 but not zero.

Results

CBD appeared to increase V̇O₂ (T2: + 38 ± 48 mL·min⁻¹, d_z: 0.25–1.35), ratings of pleasure (T1: + 0.7 ± 0.9, d_z: 0.22–1.32; T2: + 0.8 ± 1.1, d_z: 0.17–1.25) and BL (T2: + 3.3 ± 6.4 mmol·L⁻¹, d_z: > 0.00–1.03) during RUN 1 compared to placebo. No differences in HR, RPE, BG or RER were observed between treatments. CBD appeared to increase V̇O_2max (+ 119 ± 206 mL·min⁻¹, d_z: 0.06–1.10) and RER_max (+ 0.04 ± 0.05 d_z: 0.24–1.34) during RUN 2 compared to placebo. No differences in TTE or HR_max were observed between treatments. Exercise increased serum interleukin (IL)-6, IL-1β, tumour necrosis factor-α, lipopolysaccharide and myoglobin concentrations (i.e. Baseline vs. Post-RUN 1, Post-RUN 2 and/or 1-h Post-RUN 2, p’s < 0.05). However, the changes were small, making it difficult to reliably evaluate the effect of CBD, where an effect appeared to be present. Plasma concentrations of the endogenous cannabinoid, anandamide (AEA), increased Post-RUN 1 and Post-RUN 2, relative to Baseline and Pre-RUN 1 (p’s < 0.05). CBD appeared to reduce AEA concentrations Post-RUN 2, compared to placebo (− 0.95 ± 0.64 pmol·mL⁻¹, d_z: − 2.19, − 0.79).

Conclusion

CBD appears to alter some key physiological and psychological responses to aerobic exercise without impairing performance. Larger studies are required to confirm and better understand these preliminary findings.

Trial Registration This investigation was approved by the Sydney Local Health District’s Human Research Ethics Committee (2020/ETH00226) and registered with the Australia and New Zealand Clinical Trials Registry (ACTRN12620000941965).

Supplementary Information

The online version contains supplementary material available at 10.1186/s40798-022-00417-y.

Non-psychotropic phytocannabinoid interactions with voltage-gated sodium channels: An update on cannabidiol and cannabigerol

Phytocannabinoids, found in the plant, Cannabis sativa, are an important class of natural compounds with physiological effects. These compounds can be generally divided into two classes: psychoactive and non-psychoactive. Those which do not impart psychoactivity are assumed to predominantly function via endocannabinoid receptor (CB) -independent pathways and molecular targets, including other receptors and ion channels. Among these targets, the voltage-gated sodium (Nav) channels are particularly interesting due to their well-established role in electrical signalling in the nervous system. The interactions between the main non-psychoactive phytocannabinoid, cannabidiol (CBD), and Nav channels were studied in detail. In addition to CBD, cannabigerol (CBG), is another non-psychoactive molecule implicated as a potential therapeutic for several conditions, including pain via interactions with Nav channels. In this mini review, we provide an update on the interactions of Nav channels with CBD and CBG.

Multiomic Analysis Reveals Disruption of Cholesterol Homeostasis by Cannabidiol in Human Cell Lines

The nonpsychoactive cannabinoid, cannabidiol (CBD), is Food and Dug Administration approved for treatment of two drug-resistant epileptic disorders and is seeing increased use among the general public, yet the mechanisms that underlie its therapeutic effects and side-effect profiles remain unclear. Here, we report a systems-level analysis of CBD action in human cell lines using temporal multiomic profiling. FRET-based biosensor screening revealed that CBD elicits a sharp rise in cytosolic calcium, and activation of AMP-activated protein kinase in human keratinocyte and neuroblastoma cell lines. CBD treatment leads to alterations in the abundance of metabolites, mRNA transcripts, and proteins associated with activation of cholesterol biosynthesis, transport, and storage. We found that CBD rapidly incorporates into cellular membranes, alters cholesterol accessibility, and disrupts cholesterol-dependent membrane properties. Sustained treatment with high concentrations of CBD induces apoptosis in a dose-dependent manner. CBD-induced apoptosis is rescued by inhibition of cholesterol synthesis and potentiated by compounds that disrupt cholesterol trafficking and storage. Our data point to a pharmacological interaction of CBD with cholesterol homeostasis pathways, with potential implications in its therapeutic use.

Cannabidiol Impairs Brain Mitochondrial Metabolism and Neuronal Integrity

Background: The mechanisms underlying the clinical effects of CBD remain poorly understood. Given the increasing evidence for CBD's effects on mitochondria, we sought to examine in more detail whether CBD impacts mitochondrial function and neuronal integrity. Methods: We utilized BE(2)-M17 neuroblastoma cells or acutely isolated brain mitochondria from rodents using a Seahorse extracellular flux analyzer and a fluorescent spectrofluorophotometer assay. Mitochondrial ion channel activity and hippocampal long-term potentiation were measured using standard cellular electrophysiological methods. Spatial learning/memory function was evaluated using the Morris water maze task. Plasma concentrations of CBD were assessed with liquid chromatography-mass spectrometry, and cellular viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction neuronal injury assay. Results: At low micromolar concentrations, CBD reduced mitochondrial respiration, the threshold for mitochondrial permeability transition, and calcium uptake, blocked a novel mitochondrial chloride channel, and reduced the viability of hippocampal cells. These effects were paralleled by in vitro and in vivo learning/memory deficits. We further found that these effects were independent of cannabinoid receptor 1 and mitochondrial G-protein-coupled receptor 55. Conclusion: Our results provide evidence for concentration- and dose-dependent toxicological effects of CBD, findings that may bear potential relevance to clinical populations.

Cannabidiol’s Multifactorial Mechanisms Has Therapeutic Potential for Aneurysmal Subarachnoid Hemorrhage: a Review

Subarachnoid hemorrhage (SAH) is a major health burden that accounts for approximately 5% of all strokes. The most common cause of a non-traumatic SAH is the rupture of a cerebral aneurysm. The most common symptom associated with SAH is a headache, often described as “the worst headache of my life.” Delayed cerebral ischemia (DCI) is a major factor associated with patient mortality following SAH and is often associated with SAH-induced cerebral vasospasm (CV). Cannabidiol (CBD) is emerging as a potential drug for many therapeutic purposes, including epilepsy, anxiety, and pain relief. We aim to review the potential use of CBD as a treatment option for post-SAH critically ill patients. Through a literature review, we evaluated the known pharmacology and physiological effects of CBD and correlated those with the pathophysiological outcomes associated with cerebral vasospasm following subarachnoid hemorrhage. Although overlap exists, data were formatted into three major categories: anti-inflammatory, vascular, and neuroprotective effects. Based on the amount of information known about the actions of CBD, we hypothesize the anti-inflammatory effects are likely to be the most promising therapeutic mechanism. However, its cardiovascular effects through calcium regulation and its neuroprotective effects against cell death, excitotoxicity, and oxidative stress are all plausible mechanisms by which post-SAH critically ill patients may benefit from both early and late intervention with CBD. More research is needed to better understand if and how CBD might affect neurological and vascular functions in the brain following injury such as subarachnoid hemorrhage.

Cannabidiol: Influence on B Cells, Peripheral Blood Mononuclear Cells, and Peripheral Blood Mononuclear Cell/Rheumatoid Arthritis Synovial Fibroblast Cocultures

Background: Cannabidiol (CBD), one major nonintoxicating phytocannabinoid from Cannabis sativa demonstrated anti-inflammatory effects in animal models of several inflammatory conditions, including arthritis. However, it is still unknown which cell types mediate these anti-inflammatory effects of CBD, and, since CBD binds to a plethora of receptors and enzymes, it is complicated to pinpoint its mechanism of action. In this study, we elucidate the effects of CBD on B cells and peripheral blood mononuclear cells (PBMCs) in respect to survival, calcium mobilization, drug uptake, and cytokine (IL-6, IL-10, and TNF) and immunoglobulin production. Methods: Modulation of intracellular calcium and drug uptake in B cells was determined by using the fluorescent dyes Cal-520 and PoPo3, respectively. Cytokine and immunoglobulin production was evaluated by enzyme-linked immunosorbent assay. PBMC composition and B cell survival after CBD treatment was assessed by flow cytometry. Results: B cells express two major target receptors for CBD, TRPV2 (transient receptor potential vanilloid 2) and TRPA1 (transient receptor potential ankyrin 1), which are not regulated by B cell activation. CBD increased intracellular calcium levels in mouse and human B cells, which was accompanied by enhanced uptake of PoPo3. These effects were not dependent on transient receptor potential channel activation. CBD increased the number of early apoptotic B cells at the expense of viable cells and diminished interleukin (IL)-10 and tumor necrosis factor (TNF) production when activated T cell independently. In PBMCs, CBD increased IL-10 production when B cells were activated T cell dependent, while decreasing TNF levels when activated T cell independently. In PBMC/rheumatoid synovial fibroblast cocultures, CBD reduced IL-10 production when B cells were activated T cell independently. Immunoglobulin M production was augmented by CBD when B cells were activated with CpG. Conclusion: CBD is able to provide pro- and anti-inflammatory effects in isolated B cells and PBMCs. This is dependent on the activating stimulus (T cell dependent or independent) and concentration of CBD. Therefore, CBD might be used to dampen B cell activity in autoimmune conditions such as rheumatoid arthritis, in which B cells are activated by specific autoantigens.

Mitochondrial adaptation in cancer drug resistance: prevalence, mechanisms, and management

Drug resistance represents a major obstacle in cancer management, and the mechanisms underlying stress adaptation of cancer cells in response to therapy-induced hostile environment are largely unknown. As the central organelle for cellular energy supply, mitochondria can rapidly undergo dynamic changes and integrate cellular signaling pathways to provide bioenergetic and biosynthetic flexibility for cancer cells, which contributes to multiple aspects of tumor characteristics, including drug resistance. Therefore, targeting mitochondria for cancer therapy and overcoming drug resistance has attracted increasing attention for various types of cancer. Multiple mitochondrial adaptation processes, including mitochondrial dynamics, mitochondrial metabolism, and mitochondrial apoptotic regulatory machinery, have been demonstrated to be potential targets. However, recent increasing insights into mitochondria have revealed the complexity of mitochondrial structure and functions, the elusive functions of mitochondria in tumor biology, and the targeting inaccessibility of mitochondria, which have posed challenges for the clinical application of mitochondrial-based cancer therapeutic strategies. Therefore, discovery of both novel mitochondria-targeting agents and innovative mitochondria-targeting approaches is urgently required. Here, we review the most recent literature to summarize the molecular mechanisms underlying mitochondrial stress adaptation and their intricate connection with cancer drug resistance. In addition, an overview of the emerging strategies to target mitochondria for effectively overcoming chemoresistance is highlighted, with an emphasis on drug repositioning and mitochondrial drug delivery approaches, which may accelerate the application of mitochondria-targeting compounds for cancer therapy.

Cannabidiol Regulates PPARγ-Dependent Vesicle Formation as well as Cell Death in A549 Human Lung Cancer Cells

Extracts of phytocannabinoids from Cannabis sativa have been studied for therapeutic purposes. Although nonpsychoactive CBD has been studied as a promising anticancer drug because it induces apoptosis in many cancer cells, it is also known to induce several physiological changes. In this study, we clarify the functional role it plays in the morphological characteristics of intracellular vesicle formation as well as apoptosis in A549 human lung cancer cells. CBD treatment shows growth inhibition at concentrations above 20 μM, but FACS analysis shows low efficacy in terms of cell death. Microscopic observations suggest that multiple vesicles were detected in the cytoplasmic region of CBD-treated A549 cells. CBD treatment upregulates apoptosis-related proteins, such as p53, PARP, RIP1, RIP3, Atg12, and Beclin, indicating that CBD regulates several types of cell death. CBD treatment also induced E-cadherin, PPARγ, clathrin, β-adaptin, and Tsg101, also known to be cellular-differentiation inducers or vesicle-formation components. Treatment combining CBD with GW9662, a PPARγ inhibitor, reduced CBD-induced cytoplasmic vesicle formation. This indicates that PPARγ regulates the vesicle-formation mechanism. However, CBD-treated E-cad KO clones did not show this regulatory mechanism. These results elucidate the pharmacological and molecular networks associated with CBD in PPARγ-dependent vesicle formation and the induction of apoptosis.

The Combination of Δ9-Tetrahydrocannabinol and Cannabidiol Suppresses Mitochondrial Respiration of Human Glioblastoma Cells via Downregulation of Specific Respiratory Chain Proteins

Simple Summary

Cannabidiol (CBD) is a phytocannabinoid from Cannabis sativa L. that exhibits no psychoactivity and, like the psychoactive cannabinoid Δ⁹-tetrahydrocannabinol (THC), shows anticancer effects in preclinical cell and animal models. Previous studies have indicated a stronger cancer-targeting effect when THC and CBD are combined. Here, we investigated how the combination of THC and CBD in a 1:1 ratio affects glioblastoma cell survival. The compounds were found to synergistically enhance cell death, which was attributed to mitochondrial damage and disruption of energy metabolism. A detailed look at the mitochondrial electron transfer chain showed that THC/CBD selectively decreased certain subunits of complexes I and IV. These data highlight the fundamental changes in cellular energy metabolism when cancer cells are exposed to a mixture of cannabinoids and underscore the potential of combining cannabinoids in cancer treatment.

Abstract

Phytocannabinoids represent a promising approach in glioblastoma therapy. Previous work has shown that a combined treatment of glioblastoma cells with submaximal effective concentrations of psychoactive Δ⁹-tetrahydrocannabinol (THC) and non-psychoactive cannabidiol (CBD) greatly increases cell death. In the present work, the glioblastoma cell lines U251MG and U138MG were used to investigate whether the combination of THC and CBD in a 1:1 ratio is associated with a disruption of cellular energy metabolism, and whether this is caused by affecting mitochondrial respiration. Here, the combined administration of THC and CBD (2.5 µM each) led to an inhibition of oxygen consumption rate and energy metabolism. These effects were accompanied by morphological changes to the mitochondria, a release of mitochondrial cytochrome c into the cytosol and a marked reduction in subunits of electron transport chain complexes I (NDUFA9, NDUFB8) and IV (COX2, COX4). Experiments with receptor antagonists and inhibitors showed that the degradation of NDUFA9 occurred independently of the activation of the cannabinoid receptors CB₁, CB₂ and TRPV1 and of usual degradation processes mediated via autophagy or the proteasomal system. In summary, the results describe a previously unknown mitochondria-targeting mechanism behind the toxic effect of THC and CBD on glioblastoma cells that should be considered in future cancer therapy, especially in combination strategies with other chemotherapeutics.

Effects of Cannabidiol on Locomotor Activity

Cannabidiol (CBD) is the second cannabinoid, in order of importance after Δ9-tetrahydrocannabinol (THC), from Cannabis sativa. Unlike THC, CBD does not cause psychotomimetic effects, and although these compounds have the same chemical formula, their pharmacological characteristics are not equivalent. Preclinical studies suggest that CBD has anti-inflammatory, analgesic, anxiolytic, antiemetic, anticonvulsant, and antipsychotic properties and influences the sleep–wake cycle. The evaluation of effects on spontaneous motor activity is crucial in experimental pharmacology, and the careful measurement of laboratory animal movement is an established method to recognize the effects of stimulant and depressant drugs. The potential influence of CBD on locomotor activity has been investigated through numerous in vivo experiments. However, there is no clear picture of the impact of CBD on these issues, even though it is administered alone for medical uses and sold with THC as a drug for pain caused by muscle spasms in multiple sclerosis, and it was recently licensed as a drug for severe forms of infantile epilepsy. On this basis, with the aim of developing deeper knowledge of this issue, scientific data on CBD’s influence on locomotor activity are discussed here. We conducted research using PubMed, Scopus, Google Scholar, and a search engine for literature between January 2009 and December 2021 on life sciences and biomedical topics using the keywords “motor activity”, “locomotor activity”, and “locomotion” in combination with “cannabidiol”. In this article, we discuss findings describing the effects on locomotor activity of the CBD precursor cannabidiolic acid and of CBD alone or in combination with THC, together with the effects of CBD on locomotor modifications induced by diseases and on locomotor changes induced by other substances.

Overcoming Steroid Resistance in Pediatric Acute Lymphoblastic Leukemia-The State-of-the-Art Knowledge and Future Prospects

Acute lymphoblastic leukemia (ALL) is the most common malignancy among children. Despite the enormous progress in ALL therapy, resulting in achieving a 5-year survival rate of up to 90%, the ambitious goal of reaching a 100% survival rate is still being pursued. A typical ALL treatment includes three phases: remission induction and consolidation and maintenance, preceded by a prednisone prephase. Poor prednisone response (PPR) is defined as the presence of ≥1.0 × 10⁹ blasts/L in the peripheral blood on day eight of therapy and results in significantly frequent relapses and worse outcomes. Hence, identifying risk factors of steroid resistance and finding methods of overcoming that resistance may significantly improve patients' outcomes. A mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK-ERK) pathway seems to be a particularly attractive target, as its activation leads to steroid resistance via a phosphorylating Bcl-2-interacting mediator of cell death (BIM), which is crucial in the steroid-induced cell death. Several mutations causing activation of MAPK-ERK were discovered, notably the interleukin-7 receptor (IL-7R) pathway mutations in T-cell ALL and rat sarcoma virus (Ras) pathway mutations in precursor B-cell ALL. MAPK-ERK pathway inhibitors were demonstrated to enhance the results of dexamethasone therapy in preclinical ALL studies. This report summarizes steroids' mechanism of action, resistance to treatment, and prospects of steroids therapy in pediatric ALL.

Cannabidiol on the Path from the Lab to the Cancer Patient: Opportunities and Challenges

Cannabidiol (CBD), a major non-psychotropic component of cannabis, is receiving growing attention as a potential anticancer agent. CBD suppresses the development of cancer in both in vitro (cancer cell culture) and in vivo (xenografts in immunodeficient mice) models. For critical evaluation of the advances of CBD on its path from laboratory research to practical application, in this review, we wish to call the attention of scientists and clinicians to the following issues: (a) the biological effects of CBD in cancer and healthy cells; (b) the anticancer effects of CBD in animal models and clinical case reports; (c) CBD’s interaction with conventional anticancer drugs; (d) CBD’s potential in palliative care for cancer patients; (e) CBD’s tolerability and reported side effects; (f) CBD delivery for anticancer treatment.

Cannabidiol and Other Phytocannabinoids as Cancer Therapeutics

Preclinical models provided ample evidence that cannabinoids are cytotoxic against cancer cells. Among the best studied phytocannabinoids, cannabidiol (CBD) is most promising for the treatment of cancer as it lacks the psychotomimetic properties of delta-9-tetrahydrocannabinol (THC). In vitro studies and animal experiments point to a concentration- (dose-)dependent anticancer effect. The effectiveness of pure compounds versus extracts is the subject of an ongoing debate. Actual results demonstrate that CBD-rich hemp extracts must be distinguished from THC-rich cannabis preparations. Whereas pure CBD was superior to CBD-rich extracts in most in vitro experiments, the opposite was observed for pure THC and THC-rich extracts, although exceptions were noted. The cytotoxic effects of CBD, THC and extracts seem to depend not only on the nature of cannabinoids and the presence of other phytochemicals but also largely on the nature of cell lines and test conditions. Neither CBD nor THC are universally efficacious in reducing cancer cell viability. The combination of pure cannabinoids may have advantages over single agents, although the optimal ratio seems to depend on the nature of cancer cells; the existence of a 'one size fits all' ratio is very unlikely. As cannabinoids interfere with the endocannabinoid system (ECS), a better understanding of the circadian rhythmicity of the ECS, particularly endocannabinoids and receptors, as well as of the rhythmicity of biological processes related to the growth of cancer cells, could enhance the efficacy of a therapy with cannabinoids by optimization of the timing of the administration, as has already been reported for some of the canonical chemotherapeutics. Theoretically, a CBD dose administered at noon could increase the peak of anandamide and therefore the effects triggered by this agent. Despite the abundance of preclinical articles published over the last 2 decades, well-designed controlled clinical trials on CBD in cancer are still missing. The number of observations in cancer patients, paired with the anticancer activity repeatedly reported in preclinical in vitro and in vivo studies warrants serious scientific exploration moving forward.

Cannabidiol activates PINK1-Parkin-dependent mitophagy and mitochondrial-derived vesicles

The PINK1/Parkin pathway plays an important role in maintaining a healthy pool of mitochondria. Activation of this pathway can lead to apoptosis, mitophagy, or mitochondrial-derived vesicle formation, depending on the nature of mitochondrial damage. The signaling by which PINK/Parkin activation leads to these different mitochondrial outcomes remains understudied. Here we present evidence that cannabidiol (CBD) activates the PINK1-Parkin pathway in a unique manner. CBD stimulates PINK1-dependent Parkin mitochondrial recruitment similarly to other well-studied Parkin activators but with a distinctive shift in the temporal dynamics and mitochondrial fates. The mitochondrial permeability transition pore inhibitor cyclosporine A exclusively diminished the CBD-induced PINK1/Parkin activation and its associated mitochondrial effects. Unexpectedly, CBD treatment also induced elevated production of mitochondrial-derived vesicles (MDV), a potential quality control mechanism that may help repair partial damaged mitochondria. Our results suggest that CBD may engage the PINK1-Parkin pathway to produce MDV and repair mitochondrial lesions via mitochondrial permeability transition pore opening. This work uncovered a novel link between CBD and PINK1/Parkin-dependent MDV production in mitochondrial health regulation.

Channelopathy of Dravet Syndrome and Potential Neuroprotective Effects of Cannabidiol

Dravet syndrome (DS) is a channelopathy, neurodevelopmental, epileptic encephalopathy characterized by seizures, developmental delay, and cognitive impairment that includes susceptibility to thermally induced seizures, spontaneous seizures, ataxia, circadian rhythm and sleep disorders, autistic-like behaviors, and premature death. More than 80% of DS cases are linked to mutations in genes which encode voltage-gated sodium channel subunits, SCN1A and SCN1B, which encode the Nav1.1α subunit and Nav1.1β1 subunit, respectively. There are other gene mutations encoding potassium, calcium, and hyperpolarization-activated cyclic nucleotide-gated (HCN) channels related to DS. One-third of patients have pharmacoresistance epilepsy. DS is unresponsive to standard therapy. Cannabidiol (CBD), a non-psychoactive phytocannabinoid present in Cannabis, has been introduced for treating DS because of its anticonvulsant properties in animal models and humans, especially in pharmacoresistant patients. However, the etiological channelopathiological mechanism of DS and action mechanism of CBD on the channels are unclear. In this review, we summarize evidence of the direct and indirect action mechanism of sodium, potassium, calcium, and HCN channels in DS, especially sodium subunits. Some channels' loss-of-function or gain-of-function in inhibitory or excitatory neurons determine the balance of excitatory and inhibitory are associated with DS. A great variety of mechanisms of CBD anticonvulsant effects are focused on modulating these channels, especially sodium, calcium, and potassium channels, which will shed light on ionic channelopathy of DS and the precise molecular treatment of DS in the future.

Cannabinoid Cancer Biology and Prevention

Plant-based, synthetic, and endogenous cannabinoids have been shown to control a diverse array of biological processes, including regulation of cell fate across cancers. Their promise as broad-based antitumor agents in preclinical models has led to the initiation of pilot clinical trials. Session 5 of the National Cancer Institute's Cannabis, Cannabinoids and Cancer Research Symposium provides an overview of this research topic. Overall, the presentations highlight cannabinoid signal transduction and specific molecular mechanisms underlying cannabinoid antitumor activity. They also demonstrate the broad-based antitumor activity of the plant-based, synthetic, and endogenous cannabinoid compounds. Importantly, evidence is presented demonstrating when cannabinoids may be contraindicated as a treatment for cancer, as in the case of human papilloma virus-meditated oropharynx cancer or potentially other p38 MAPK pathway-driven cancers. Finally, it is discussed that a key to advancing cannabinoids into the clinic is to conduct well-designed, large-scale clinical trials to determine whether cannabinoids are effective antitumor agents in cancer patients.

Cannabidiol Induces Cell Death in Human Lung Cancer Cells and Cancer Stem Cells

Currently, there is no effective therapy against lung cancer due to the development of resistance. Resistance contributes to disease progression, recurrence, and mortality. The presence of so-called cancer stem cells could explain the ineffectiveness of conventional treatment, and the development of successful cancer treatment depends on the targeting also of cancer stem cells. Cannabidiol (CBD) is a cannabinoid with anti-tumor properties. However, the effects on cancer stem cells are not well understood. The effects of CBD were evaluated in spheres enriched in lung cancer stem cells and adherent lung cancer cells. We found that CBD decreased viability and induced cell death in both cell populations. Furthermore, we found that CBD activated the effector caspases 3/7, increased the expression of pro-apoptotic proteins, increased the levels of reactive oxygen species, as well as a leading to a loss of mitochondrial membrane potential in both populations. We also found that CBD decreased self-renewal, a hallmark of cancer stem cells. Overall, our results suggest that CBD is effective against the otherwise treatment-resistant cancer stem cells and joins a growing list of compounds effective against cancer stem cells. The effects and mechanisms of CBD in cancer stem cells should be further explored to find their Achilles heel.

Decreasing sperm quality in mice subjected to chronic cannabidiol exposure: New insights of cannabidiol-mediated male reproductive toxicity

Cannabidiol (CBD) is a natural cannabinoid present in the Cannabis sativa plant, widely prescribed as an anticonvulsant drug, especially for pediatric use. However, its effects on male reproduction are still little investigated. Therefore, the present study assessed the effects of CBD on the spermatogenesis and sperm quality. For this, twenty-one-day-old Swiss mice received CBD for 34 consecutive days by gavage at doses of either 15 or 30 mg/kg. Chronic exposure to CBD decreased the frequency of stages VII-VIII and XII of spermatogenesis and an increase in the frequency of stage IX were noted. Furthermore, the seminiferous epithelium height reduced at stage IX and increased at stage XII in both CBD-treated groups. There was a significant rise of sperm DNA damage, while no genotoxic effects were observed in leukocytes. The activities of superoxide dismutase and catalase decreased, while malondialdehyde levels increased in the sperm of mice treated with a higher dose of CBD. Mice exposed to 30 mg/kg of CBD showed a reduction in the mobile spermatozoa percentage and in curvilinear velocity, while straight line and average path velocity decreased in both treated groups. The number of acrosome-intact spermatozoa declined in the CBD 30 group, and the number of abnormal acrosomes raised in both CBD groups. On the other hand, the weight of reproductive organs, sperm count, and hormone levels were not affected by CBD treatment. These findings show that dysregulation of the endocannabinoid system by CBD can reduce sperm quality. The mechanisms responsible may be associated with disorders during spermatogenesis, especially during the final stages of nuclear remodelling and assembly of acrosome. However, changes in mitochondrial function, as well as the reduction on the antioxidant enzyme activities during epididymal transit, at least partly, may also be involved.

Analysis of toxicity effects of delta-9-tetrahydrocannabinol on isolated rat heart mitochondria

Mitochondria have the main roles in myocardial tissue homeostasis, through providing ATP for the vital enzymes in intermediate metabolism, contractile apparatus and maintaining ion homeostasis. Mitochondria-related cardiotoxicity results from the exposure with illicit drugs have previously reported. These illicit drugs interference with processes of normal mitochondrial homeostasis and lead to mitochondrial dysfunction and mitochondrial-related oxidative stress. Cannabis consumption has been shown to cause ventricular tachycardia, to increase the risk of myocardial infarction (MI) and potentially sudden death. Here, we investigated this hypothesis that delta-9-tetrahydrocannabinol (Delta-9-THC) as a main cannabinoid found in cannabis could directly cause mitochondrial dysfunction. Cardiac mitochondria were isolated with mechanical lysis and differential centrifugation form rat heart. The isolated cardiac mitochondria were treated with different concentrations of THC (1, 5, 10, 50, 100 and 500 µM) for 1 hour at 37 °C. Then, succinate dehydrogenase (SDH) activity, mitochondrial swelling, reactive oxygen species (ROS) formation, mitochondrial membrane potential (MMP) collapse and lipid peroxidation were measured in the treated and nontreated isolated cardiac mitochondria. Our observation showed that THC did not cause a deleterious alteration in mitochondrial functions, ROS production, MMP collapse, mitochondrial swelling, oxidative stress and lipid peroxidation in used concentrations (5-100 µM), even in several tests, toxicity showed a decreasing trend. Altogether, the results of the current study showed that THC is not directly toxic in isolated cardiac mitochondria, and even may be helpful in reducing mitochondrial toxicity.

Contribution of non-selective membrane channels and receptors in epilepsy

Overcoming refractory epilepsy's resistance to the combination of antiepileptic drugs (AED), mitigating side effects, and preventing sudden unexpected death in epilepsy are critical goals for therapy of this disorder. Current therapeutic strategies are based primarily on neurocentric mechanisms, overlooking the participation of astrocytes and microglia in the pathophysiology of epilepsy. This review is focused on a set of non-selective membrane channels (permeable to ions and small molecules), including channels and ionotropic receptors of neurons, astrocytes, and microglia, such as: the hemichannels formed by Cx43 and Panx1; the purinergic P2X7 receptors; the transient receptor potential vanilloid (TRPV1 and TRPV4) channels; calcium homeostasis modulators (CALHMs); transient receptor potential canonical (TRPC) channels; transient receptor potential melastatin (TRPM) channels; voltage-dependent anion channels (VDACs) and volume-regulated anion channels (VRACs), which all have in common being activated by epileptic activity and the capacity to exacerbate seizure intensity. Specifically, we highlight evidence for the activation of these channels/receptors during epilepsy including neuroinflammation and oxidative stress, discuss signaling pathways and feedback mechanisms, and propose the functions of each of them in acute and chronic epilepsy. Studying the role of these non-selective membrane channels in epilepsy and identifying appropriate blockers for one or more of them could provide complementary therapies to better alleviate the disease.

Cannabidiol Induces Apoptosis and Perturbs Mitochondrial Function in Human and Canine Glioma Cells

Cannabidiol (CBD), the major non-psychoactive compound found in cannabis, is frequently used both as a nutraceutical and therapeutic. Despite anecdotal evidence as an anticancer agent, little is known about the effect CBD has on cancer cells. Given the intractability and poor prognoses of brain cancers in human and veterinary medicine, we sought to characterize the in vitro cytotoxicity of CBD on human and canine gliomas. Glioma cells treated with CBD showed a range of cytotoxicity from 4.9 to 8.2 μg/ml; canine cells appeared to be more sensitive than human. Treatment with >5 μg/ml CBD invariably produced large cytosolic vesicles. The mode of cell death was then interrogated using pharmacologic inhibitors. Inhibition of apoptosis was sufficient to rescue CBD-mediated cytotoxicity. Inhibition of RIPK3, a classical necroptosis kinase, also rescued cells from death and prevented the formation of the large cytosolic vesicles. Next, cellular mitochondrial activity in the presence of CBD was assessed and within 2 hours of treatment CBD reduced oxygen consumption in a dose dependent manner with almost complete ablation of activity at 10 μg/ml CBD. Fluorescent imaging with a mitochondrial-specific dye revealed that the large cytosolic vesicles were, in fact, swollen mitochondria. Lastly, calcium channels were pharmacologically inhibited and the effect on cell death was determined. Inhibition of mitochondrial channel VDAC1, but not the TRPV1 channel, rescued cells from CBD-mediated cytotoxicity. These results demonstrate the cytotoxic nature of CBD in human and canine glioma cells and suggest a mechanism of action involving dysregulation of calcium homeostasis and mitochondrial activity.

VDACs: An Outlook on Biochemical Regulation and Function in Animal and Plant Systems

The voltage-dependent anion channels (VDACs) are the most abundant proteins present on the outer mitochondrial membrane. They serve a myriad of functions ranging from energy and metabolite exchange to highly debatable roles in apoptosis. Their role in molecular transport puts them on the center stage as communicators between cytoplasmic and mitochondrial signaling events. Beyond their general role as interchangeable pores, members of this family may exhibit specific functions. Even after nearly five decades of their discovery, their role in plant systems is still a new and rapidly emerging field. The information on biochemical regulation of VDACs is limited. Various interacting proteins and post-translational modifications (PTMs) modulate VDAC functions, amongst these, phosphorylation is quite noticeable. In this review, we have tried to give a glimpse of the recent advancements in the biochemical/interactional regulation of plant VDACs. We also cover a critical analysis on the importance of PTMs in the functional regulation of VDACs. Besides, the review also encompasses numerous studies which can identify VDACs as a connecting link between Ca2+ and reactive oxygen species signaling in special reference to the plant systems.

Cannabidiol disrupts apoptosis, autophagy and invasion processes of placental trophoblasts

Cannabidiol (CBD) is a constituent of Cannabis sativa without psychotropic activity, whose medical benefits have been recognised. However, little is known about the potential toxic effects of CBD on reproductive health. Placental development involves tightly controlled processes of cell proliferation, differentiation, apoptosis, autophagy and migration/invasion of trophoblast cells. Cannabis use by pregnant women has been increasing, mainly for the relief of nausea associated with the first trimester, which raises great concern. Regarding the crucial role of cytotrophoblast cells (CTs) and extravillous trophoblasts (EVTs) in placentation, the effects of CBD (1-10 µM) were studied, using in vitro model systems BeWo and HTR-8/SVneo cell lines, respectively. CBD causes cell viability loss in a dose-dependent manner, disrupts cell cycle progression and induces apoptosis through the mitochondrial pathway, on both cell models. Moreover, CBD induces autophagy only in HTR-8/SVneo cells, being this process a promoter of apoptosis. Hypoxia-responsive genes HIF1A and SPP1 were also increased in CBD-treated HTR-8/SVneo cells suggesting a role for HIF-1α in the apoptotic and autophagic processes. In addition, CBD was able to decrease HTR-8/SVneo cell migration. Therefore, CBD interferes with trophoblast turnover and placental remodelling, which can have a considerable impact on pregnancy outcome. Thus, from an in vitro perspective our study adds new evidence for the potential negative impact of cannabis use by pregnant women.

Targeting mitochondrial ion channels for cancer therapy

Pharmacological targeting of mitochondrial ion channels is emerging as a promising approach to eliminate cancer cells; as most of these channels are differentially expressed and/or regulated in cancer cells in comparison to healthy ones, this strategy may selectively eliminate the former. Perturbation of ion fluxes across the outer and inner membranes is linked to alterations of redox state, membrane potential and bioenergetic efficiency. This leads to indirect modulation of oxidative phosphorylation, which is/may be fundamental for both cancer and cancer stem cell survival. Furthermore, given the crucial contribution of mitochondria to intrinsic apoptosis, modulation of their ion channels leading to cytochrome c release may be of great advantage in case of resistance to drugs triggering apoptotic events upstream of the mitochondrial phase. In the present review, we give an overview of the known mitochondrial ion channels and of their modulators capable of killing cancer cells. In addition, we discuss state-of-the-art strategies using mitochondriotropic drugs or peptide-based approaches allowing a more efficient and selective targeting of mitochondrial ion channel-linked events.

Regulatory Effects of Cannabidiol on Mitochondrial Functions: A Review

Cannabidiol (CBD) is part of a group of phytocannabinoids derived from Cannabissativa. Initial work on CBD presumed the compound was inactive, but it was later found to exhibit antipsychotic, anti-depressive, anxiolytic, and antiepileptic effects. In recent decades, evidence has indicated a role for CBD in the modulation of mitochondrial processes, including respiration and bioenergetics, mitochondrial DNA epigenetics, intrinsic apoptosis, the regulation of mitochondrial and intracellular calcium concentrations, mitochondrial fission, fusion and biogenesis, and mitochondrial ferritin concentration and mitochondrial monoamine oxidase activity regulation. Despite these advances, current data demonstrate contradictory findings with regard to not only the magnitude of effects mediated by CBD, but also to the direction of effects. For example, there are data indicating that CBD treatment can increase, decrease, or have no significant effect on intrinsic apoptosis. Differences between studies in cell type, cell-specific response to CBD, and, in some cases, dose of CBD may help to explain differences in outcomes. Most studies on CBD and mitochondria have utilized treatment concentrations that exceed the highest recorded plasma concentrations in humans, suggesting that future studies should focus on CBD treatments within a range observed in pharmacokinetic studies. This review focuses on understanding the mechanisms of CBD-mediated regulation of mitochondrial functions, with an emphasis on findings in neural cells and tissues and therapeutic relevance based on human pharmacokinetics.

Cannabidiol Modulates Mitochondrial Redox and Dynamics in MCF7 Cancer Cells: A Study Using Fluorescence Lifetime Imaging Microscopy of NAD(P)H

The cannabinoid, cannabidiol (CBD), is part of the plant's natural defense system that when given to animals has many useful medicinal properties, including activity against cancer cells, modulation of the immune system, and efficacy in epilepsy. Although there is no consensus on its precise mode of action as it affects many cellular targets, CBD does appear to influence mitochondrial function. This would suggest that there is a cross-kingdom ability to modulate stress resistance systems that enhance homeostasis. As NAD(P)H autofluorescence can be used as both a metabolic sensor and mitochondrial imaging modality, we assessed the potential of this technique to study the in vitro effects of CBD using 2-photon excitation and fluorescence lifetime imaging microscopy (2P-FLIM) of NAD(P)H against more traditional markers of mitochondrial morphology and cellular stress in MCF7 breast cancer cells. 2P-FLIM analysis revealed that the addition of CBD induced a dose-dependent decrease in bound NAD(P)H, with 20 µM treatments significantly decreased the contribution of bound NAD(P)H by 14.6% relative to the control (p < 0.001). CBD also increased mitochondrial concentrations of reactive oxygen species (ROS) (160 ± 53 vs. 97.6 ± 4.8%, 20 µM CBD vs. control, respectively, p < 0.001) and Ca2+ (187 ± 78 vs. 105 ± 10%, 20 µM CBD vs. the control, respectively, p < 0.001); this was associated with a significantly decreased mitochondrial branch length and increased fission. These are all suggestive of mitochondrial stress. Our results support the use of NAD(P)H autofluorescence as an investigative tool and provide further evidence that CBD can modulate mitochondrial function and morphology in a dose-dependent manner, with clear evidence of it inducing oxidative stress at higher concentrations. This continues to support emerging data in the literature and may provide further insight into its overall mode of action, not only in cancer, but potentially its function in the plant and why it can act as a medicine.

Cannabidiol Μay Prolong Survival in Patients With Glioblastoma Multiforme

BACKGROUND

Glioblastoma multiforme (GBM) is a relatively rare type of brain tumour with an incidence rate around 6 per 100,000. Even with the widely practiced combination of radiotherapy with adjuvant temozolomide, the median overall survival remains low with just 13.5 to 16 months after diagnosis.

PATIENTS AND METHODS

We retrospectively reviewed the survival of a cohort of 15 consecutive, unselected patients with histopathologically confirmed glioblastoma multiforme (GBM) who received CBD (400 to 600 mg orally per day) in addition to standard therapy (maximum resection of the tumour followed by radio-chemotherapy).

RESULTS

Of 15 patients, seven (46.7%) are now living for at least 24 months, and four (26.7%) for at least 36 months. This is more than twice as long as has been previously reported in the literature. The mean overall survival is currently 24.2 months (median 21 months).

CONCLUSION

CBD is a well supported co-medication and seems to prolong the survival of patients with glioblastoma multiforme.