Acute administration of cannabidiol in vivo suppresses ischaemia-induced cardiac arrhythmias and reduces infarct size when given at reperfusion

Pharmacology of Non-Psychoactive Phytocannabinoids and Their Potential for Treatment of Cardiometabolic Disease

The use of Cannabis sativa by humans dates back to the third millennium BC, and it has been utilized in many forms for multiple purposes, including production of fibre and rope, as food and medicine, and (perhaps most notably) for its psychoactive properties for recreational use. The discovery of Δ9-tetrahydrocannabinol (Δ9-THC) as the main psychoactive phytocannabinoid contained in cannabis by Gaoni and Mechoulam in 1964 (J Am Chem Soc 86, 1646-1647), was the first major step in cannabis research; since then the identification of the chemicals (phytocannabinoids) present in cannabis, the classification of the pharmacological targets of these compounds and the discovery that the body has its own endocannabinoid system (ECS) have highlighted the potential value of cannabis-derived compounds in the treatment of many diseases, such as neurological disorders and cancers. Although the use of Δ9-THC as a therapeutic agent is constrained by its psychoactive properties, there is growing evidence that non-psychoactive phytocannabinoids, derived from both Cannabis sativa and other plant species, as well as non-cannabinoid compounds found in Cannabis sativa, have real potential as therapeutics. This chapter will focus on the possibilities for using these compounds in the prevention and treatment of cardiovascular disease and related metabolic disturbances.

Dissecting the role of cannabinoids in vascular health and disease

Cannabis, often recognized as the most widely used illegal psychoactive substance globally, has seen a shift in its legal status in several countries and regions for both recreational and medicinal uses. This change has brought to light new evidence linking cannabis consumption to various vascular conditions. Specifically, there is an association between cannabis use and atherosclerosis, along with conditions such as arteritis, reversible vasospasm, and incidents of aortic aneurysm or dissection. Recent research has started to reveal the mechanisms connecting cannabinoid compounds to atherosclerosis development. It is well known that the primary biological roles of cannabinoids operate through the activation of cannabinoid receptor types 1 and 2. Manipulation of the endocannabinoid system, either genetically or pharmacologically, is emerging as a promising approach to address metabolic dysfunctions related to obesity. Additionally, numerous studies have demonstrated the vasorelaxant properties and potential atheroprotective benefits of cannabinoids. In preclinical trials, cannabidiol is being explored as a treatment option for monocrotaline-induced pulmonary arterial hypertension. Although existing literature suggests a direct role of cannabinoids in the pathogenesis of atherosclerosis, the correlation between cannabinoids and other vascular diseases was only reported in some case series or observational studies, and its role and precise mechanisms remain unclear. Therefore, it is necessary to summarize and update previously published studies. This review article aims to summarize the latest clinical and experimental research findings on the relationship between cannabis use and vascular diseases. It also seeks to shed light on the potential mechanisms underlying these associations, offering a comprehensive view of current knowledge in this evolving field of study.

Therapeutic potential of cannabidiol (CBD) in the treatment of cardiovascular diseases

INTRODUCTION

Cannabidiol (CBD) is the primary non-psychoactive chemical derived from Cannabis Sativa, and its growing popularity is due to its potential therapeutic properties while avoiding the psychotropic effects of other phytocannabinoids, such as tetrahydrocannabinol (THC). Numerous pre-clinical studies in cellular and animal models and human clinical trials have demonstrated a positive impact of CBD on physiological and pathological processes. Recently, the FDA approved its use for the treatment of seizures, and clinical trials to test the efficacy of CBD in myocarditis and pericarditis are ongoing.

AREAS COVERED

We herein reviewed the current literature on the reported effects of CBD in the cardiovascular system, highlighting the physiological effects and the outcomes of using CBD as a therapeutic tool in pathological conditions to address this significant global health concern.

EXPERT OPINION

The comprehensive examination of the literature emphasizes the potential of CBD as a therapeutic option for treating cardiovascular diseases through its anti-inflammatory, vasodilatory, anti-fibrotic, and antioxidant properties in different conditions such as diabetic cardiomyopathy, myocarditis, doxorubicin-induced cardiotoxicity, and ischemia-reperfusion injury.

Potential perioperative cardiovascular outcomes in cannabis/cannabinoid users. A call for caution

Background

Cannabis is one of the most widely used psychoactive substances. Its components act through several pathways, producing a myriad of side effects, of which cardiovascular events are the most life-threatening. However, only a limited number of studies address cannabis's perioperative impact on patients during noncardiac surgery.

Methods

Studies were identified by searching the PubMed, Medline, EMBASE, and Google Scholar databases using relevant keyword combinations pertinent to the topic.

Results

Current evidence shows that cannabis use may cause several cardiovascular events, including abnormalities in cardiac rhythm, myocardial infarction, heart failure, and cerebrovascular events. Additionally, cannabis interacts with anticoagulants and antiplatelet agents, decreasing their efficacy. Finally, the interplay of cannabis with inhalational and intravenous anesthetic agents may lead to adverse perioperative cardiovascular outcomes.

Conclusions

The use of cannabis can trigger cardiovascular events that may depend on factors such as the duration of consumption, the route of administration of the drug, and the dose consumed, which places these patients at risk of drug-drug interactions with anesthetic agents. However, large prospective randomized clinical trials are needed to further elucidate gaps in the body of knowledge regarding which patient population has a greater risk of perioperative complications after cannabis consumption.

Cannabidiol promotes intestinal cholesterol uptake mediated by Pregnane X receptor

Background

Cannabidiol (CBD), a non-psychoactive phytocannabinoid of cannabis, is therapeutically used as an analgesic, anti-convulsant, anti-inflammatory, and anti-psychotic drug. There is a growing concern about the adverse side effects posed by CBD usage. Pregnane X receptor (PXR) is a nuclear receptor activated by a variety of dietary steroids, pharmaceutical agents, and environmental chemicals. In addition to the role in xenobiotic metabolism, the atherogenic and dyslipidemic effects of PXR have been revealed in animal models. CBD has a low affinity for cannabinoid receptors, thus it is important to elucidate the molecular mechanisms by which CBD activates cellular signaling and to assess the possible adverse impacts of CBD on pro-atherosclerotic events in cardiovascular system, such as dyslipidemia.

Objective

Our study aims to explore the cellular and molecular mechanisms by which exposure to CBD activates human PXR and increases the risk of dyslipidemia.

Methods

Both human hepatic and intestinal cells were used to test if CBD was a PXR agonist via cell-based transfection assay. The key residues within PXR's ligand-binding pocket that CBD interacted with were investigated using computational docking study together with site-directed mutagenesis assay. The C57BL/6 wildtype mice were orally fed CBD in the presence of PXR antagonist resveratrol (RES) to determine how CBD exposure could change the plasma lipid profiles in a PXR-dependent manner. Human intestinal cells were treated with CBD and/or RES to estimate the functions of CBD in cholesterol uptake.

Results

CBD was a selective agonist of PXR with higher activities on human PXR than rodents PXRs and promoted the dissociation of human PXR from nuclear co-repressors. The key amino acid residues Met246, Ser247, Phe251, Phe288, Trp299, and Tyr306 within PXR's ligand binding pocket were identified to be necessary for the agonistic effects of CBD. Exposure to CBD increased the circulating total cholesterol levels in mice which was partially caused by the induced expression levels of the key intestinal PXR-regulated lipogenic genes. Mechanistically, CBD induced the gene expression of key intestinal cholesterol transporters, which led to the increased cholesterol uptake by intestinal cells.

Conclusion

CBD was identified as a selective PXR agonist. Exposure to CBD activated PXR signaling and increased the atherogenic cholesterol levels in plasma, which partially resulted from the ascended cholesterol uptake by intestinal cells. Our study provides potential evidence for the future risk assessment of CBD on cardiovascular disease, such as dyslipidemia.

Cannabidiol potentiates hyperpolarization-activated cyclic nucleotide-gated (HCN4) channels

Cannabidiol (CBD), the main non-psychotropic phytocannabinoid produced by the Cannabis sativa plant, blocks a variety of cardiac ion channels. We aimed to identify whether CBD regulated the cardiac pacemaker channel or the hyperpolarization-activated cyclic nucleotide-gated channel (HCN4). HCN4 channels are important for the generation of the action potential in the sinoatrial node of the heart and increased heart rate in response to β-adrenergic stimulation. HCN4 channels were expressed in HEK 293T cells, and the effect of CBD application was examined using a whole-cell patch clamp. We found that CBD depolarized the V1/2 of activation in holo-HCN4 channels, with an EC50 of 1.6 µM, without changing the current density. CBD also sped activation kinetics by approximately threefold. CBD potentiation of HCN4 channels occurred via binding to the closed state of the channel. We found that CBD's mechanism of action was distinct from cAMP, as CBD also potentiated apo-HCN4 channels. The addition of an exogenous PIP2 analog did not alter the ability of CBD to potentiate HCN4 channels, suggesting that CBD also acts using a unique mechanism from the known HCN4 potentiator PIP2. Lastly, to gain insight into CBD's mechanism of action, computational modeling and targeted mutagenesis were used to predict that CBD binds to a lipid-binding pocket at the C-terminus of the voltage sensor. CBD represents the first FDA-approved drug to potentiate HCN4 channels, and our findings suggest a novel starting point for drug development targeting HCN4 channels.

Re-evaluation of the cardioprotective effects of cannabinoids against ischemia-reperfusion injury according to the IMproving Preclinical Assessment of Cardioprotective Therapies (IMPACT) criteria

Ischemic heart disease, associated with high morbidity and mortality, represents a major challenge for the development of drug-based strategies to improve its prognosis. Results of pre-clinical studies suggest that agonists of cannabinoid CB2 receptors and multitarget cannabidiol might be potential cardioprotective strategies against ischemia-reperfusion injury. The aim of our study was to re-evaluate the cardioprotective effects of cannabinoids against ischemia-reperfusion injury according to the IMproving Preclinical Assessment of Cardioprotective Therapies (IMPACT) criteria published recently by the European Union (EU) CARDIOPROTECTION COST ACTION. To meet the minimum criteria of those guidelines, experiments should be performed (i) on healthy small animals subjected to ischemia with reperfusion lasting for at least 2 hours and (ii) confirmed in small animals with comorbidities and co-medications and (iii) in large animals. Our analysis revealed that the publications regarding cardioprotective effects of CB2 receptor agonists and cannabidiol did not meet all three strict steps of IMPACT. Thus, additional experiments are needed to confirm the cardioprotective activities of (endo)cannabinoids mainly on small animals with comorbidities and on large animals. Moreover, our publication underlines the significance of the IMPACT criteria for a proper planning of preclinical experiments regarding cardiac ischemia-reperfusion injury.

Interactions between antiepileptic drugs and direct oral anticoagulants for primary and secondary stroke prevention

INTRODUCTION

Direct oral anticoagulants (DOAC) are the guideline-recommended therapy for prevention of stroke in atrial fibrillation (AF) and venous thromboembolism. Since approximately 10% of patients using antiepileptic drugs (AED) also receive DOAC, aim of this review is to summarize data about drug-drug interactions (DDI) of DOAC with AED by using data from PubMed until December 2023.

AREAS COVERED

Of 49 AED, only 16 have been investigated regarding DDI with DOAC by case reports or observational studies. No increased risk for stroke was reported only for topiramate, zonisamide, pregabalin, and gabapentin, whereas for the remaining 12 AED conflicting results regarding the risk for stroke and bleeding were found. Further 16 AED have the potential for pharmacodynamic or pharmacokinetic DDI, but no data regarding DOAC are available. For the remaining 17 AED it is unknown if they have DDI with DOAC.

EXPERT OPINION

Knowledge about pharmacokinetic and pharmacodynamic DDI of AED and DOAC is limited and frequently restricted to in vitro and in vivo findings. Since no data about DDI with DOAC are available for 67% of AED and an increasing number of patients have a combined medication of DOAC and AED, there is an urgent need for research on this topic.

An Overview of Cannabidiol as a Multifunctional Drug: Pharmacokinetics and Cellular Effects

Cannabidiol (CBD), a non-psychoactive compound derived from Cannabis Sativa, has garnered increasing attention for its diverse therapeutic potential. This comprehensive review delves into the complex pharmacokinetics of CBD, including factors such as bioavailability, distribution, safety profile, and dosage recommendations, which contribute to the compound's pharmacological profile. CBD's role as a pharmacological inhibitor is explored, encompassing interactions with the endocannabinoid system and ion channels. The compound's anti-inflammatory effects, influencing the Interferon-beta and NF-κB, position it as a versatile candidate for immune system regulation and interventions in inflammatory processes. The historical context of Cannabis Sativa's use for recreational and medicinal purposes adds depth to the discussion, emphasizing CBD's emergence as a pivotal phytocannabinoid. As research continues, CBD's integration into clinical practice holds promise for revolutionizing treatment approaches and enhancing patient outcomes. The evolution in CBD research encourages ongoing exploration, offering the prospect of unlocking new therapeutic utility.

Cannabidiol represses miR-143 to promote cardiomyocyte proliferation and heart regeneration after myocardial infarction

Mammalian heart is capable to regenerate almost completely early after birth through endogenous cardiomyocyte proliferation. However, this regenerative capacity diminishes gradually with growth and is nearly lost in adulthood. Cannabidiol (CBD) is a major component of cannabis and has various biological activities to regulate oxidative stress, fibrosis, inflammation, and cell death. The present study was conducted to investigate the pharmacological effects of CBD on heart regeneration in post-MI mice. MI models in adult mice were constructed via coronary artery ligation, which were administrated with or without CBD. Our results demonstrate that systemic administration (10 mg/kg) of CBD markedly increased cardiac regenerative ability, reduced infarct size, and restored cardiac function in MI mice. Consistently, in vitro study also showed that CBD was able to promote the proliferation of neonatal cardiomyocytes. Mechanistically, the expression of miR-143-3p related to cardiomyocyte proliferation was significantly down-regulated in CBD-treated cardiomyocytes, while the overexpression of miR-143-3p inhibited cardiomyocyte mitosis and eliminated CBD-induced cardiomyocyte proliferation. Moreover, CBD enhanced the expression of Yap and Ctnnd1, which were demonstrated as the target genes of miR-143-3p. Silencing of Yap and Ctnnd1 hindered the proliferative effects of CBD. We further revealed that inhibition of the cannabinoid receptor 2 impeded the regulatory effect of CBD on miR-143-3p and its downstream target Yap/Ctnnd1, which ultimately eliminated the pro-proliferative effect of CBD on neonatal and adult cardiomyocytes. Taken together, CBD promotes cardiomyocyte proliferation and heart regeneration after MI via miR-143-3p/Yap/Ctnnd1 signaling pathway, which provides a new strategy for cardiac repair in adult myocardium.

The pharmacology and therapeutic role of cannabidiol in diabetes

In recent years, cannabidiol (CBD), a non-psychotropic cannabinoid, has garnered substantial interest in drug development due to its broad pharmacological activity and multi-target effects. Diabetes is a chronic metabolic disease that can damage multiple organs in the body, leading to the development of complications such as abnormal kidney function, vision loss, neuropathy, and cardiovascular disease. CBD has demonstrated significant therapeutic potential in treating diabetes mellitus and its complications owing to its various pharmacological effects. This work summarizes the role of CBD in diabetes and its impact on complications such as cardiovascular dysfunction, nephropathy, retinopathy, and neuropathy. Strategies for discovering molecular targets for CBD in the treatment of diabetes and its complications are also proposed. Moreover, ways to optimize the structure of CBD based on known targets to generate new CBD analogues are explored.

The Current State of Research on Sirtuin-Mediated Autophagy in Cardiovascular Diseases

Sirtuins belong to the class III histone deacetylases and possess nicotinamide adenine dinucleotide-dependent deacetylase activity. They are involved in the regulation of multiple signaling pathways implicated in cardiovascular diseases. Autophagy is a crucial adaptive cellular response to stress stimuli. Mounting evidence suggests a strong correlation between Sirtuins and autophagy, potentially involving cross-regulation and crosstalk. Sirtuin-mediated autophagy plays a crucial regulatory role in some cardiovascular diseases, including atherosclerosis, ischemia/reperfusion injury, hypertension, heart failure, diabetic cardiomyopathy, and drug-induced myocardial damage. In this context, we summarize the research advancements pertaining to various Sirtuins involved in autophagy and the molecular mechanisms regulating autophagy. We also elucidate the biological function of Sirtuins across diverse cardiovascular diseases and further discuss the development of novel drugs that regulate Sirtuin-mediated autophagy.

Pharmacological Evaluation of Newly Synthesized Cannabidiol Derivates on H9c2 Cells

Cannabidiol (CBD) is a nonpsychoactive phytocannabinoid that can be found in Cannabis sativa and possesses numerous pharmacological effects. Due to these promising effects, CBD can be used in a wide variety of diseases, for instance cardiovascular diseases. However, CBD, like tetrahydrocannabinol (THC), has low bioavailability, poor water solubility, and a variable pharmacokinetic profile, which hinders its therapeutic use. Chemical derivatization of CBD offers us potential ways to overcome these issues. We prepared three new CBD derivatives substituted on the aromatic ring by Mannich-type reactions, which have not been described so far for the modification of cannabinoids, and studied the protective effect they have on cardiomyocytes exposed to oxidative stress and hypoxia/reoxygenation (H/R) compared to the parent compound. An MTT assay was performed to determine the viability of rat cardiomyocytes treated with test compounds. Trypan blue exclusion and lactate dehydrogenase (LDH) release assays were carried out to study the effect of the new compounds in cells exposed to H2O2 or hypoxia/reoxygenation (H/R). Direct antioxidant activity was evaluated by a total antioxidant capacity (TAC) assay. To study antioxidant protein levels, HO-1, SOD, catalase, and Western blot analysis were carried out. pIC50 (the negative log of the IC50) values were as follows: CBD1: 4.113, CBD2: 3.995, CBD3: 4.190, and CBD: 4.671. The newly synthesized CBD derivatives prevented cell death induced by H/R, especially CBD2. CBD has the largest direct antioxidant activity. The levels of antioxidant proteins were increased differently after pretreatment with synthetic CBD derivatives and CBD. Taken together, our newly synthesized CBD derivatives are able to decrease cytotoxicity during oxidative stress and H/R. The compounds have similar or better effects than CBD on H9c2 cells.

Molecular and Cellular Mechanisms of Action of Cannabidiol

Cannabidiol (CBD) is the primary non-psychoactive chemical from Cannabis Sativa, a plant used for centuries for both recreational and medicinal purposes. CBD lacks the psychotropic effects of Δ9-tetrahydrocannabinol (Δ9-THC) and has shown great therapeutic potential. CBD exerts a wide spectrum of effects at a molecular, cellular, and organ level, affecting inflammation, oxidative damage, cell survival, pain, vasodilation, and excitability, among others, modifying many physiological and pathophysiological processes. There is evidence that CBD may be effective in treating several human disorders, like anxiety, chronic pain, psychiatric pathologies, cardiovascular diseases, and even cancer. Multiple cellular and pre-clinical studies using animal models of disease and several human trials have shown that CBD has an overall safe profile. In this review article, we summarize the pharmacokinetics data, the putative mechanisms of action of CBD, and the physiological effects reported in pre-clinical studies to give a comprehensive list of the findings and major effects attributed to this compound.

Cannabidiol goes nuclear: The role of PPARγ

BACKGROUND

Cannabidiol (CBD) is one of the main phytocannabinoids found in Cannabis sativa. In contrast to Δ9-tetrahydrocannabinol, it has a low affinity for cannabinoid receptors CB1 and CB2, thereby it does not induce significant psychoactive effects. However, CBD may interact with other receptors, including peroxisome proliferator-activated receptor gamma (PPARγ). CBD is a PPARγ agonist and changes its expression. There is considerable evidence that CBD's effects are mediated by its interaction with PPARγ. So, we reviewed studies related to the interaction of CBD and PPARγ.

METHODS

In this comprehensive literature review, the term 'cannabidiol' was used in combination with the following keywords including 'PPARγ', 'Alzheimer's disease', 'Parkinson's disease', 'seizure', 'multiple sclerosis', 'immune system', 'cardiovascular system', 'cancer', and 'adipogenesis'. PubMed, Web of Science, and Google Scholar were searched until December 20, 2022. A total of 78 articles were used for the reviewing process.

RESULTS

CBD, via activation of PPARγ, promotes significant pharmacological effects. The present review shows that the effects of CBD on Alzheimer's disease and memory, Parkinson's disease and movement disorders, multiple sclerosis, anxiety and depression, cardiovascular system, immune system, cancer, and adipogenesis are mediated, at least in part, via PPARγ.

CONCLUSION

CBD not only activates PPARγ but also affects its expression in the body. It was suggested that the late effects of CBD are mediated via PPARγ activation. We suggested that CBD's chemical structure is a good backbone for developing new dual agonists. Combining it with other chemicals enhances their biological effectiveness while reducing their dosage. The present study indicated that PPARγ is a key target for CBD, and its activation by CBD should be considered in all future studies.

How do phytocannabinoids affect cardiovascular health? An update on the most common cardiovascular diseases

Cardiovascular disease (CVD) causes millions of deaths worldwide each year. Despite the great progress in therapies available for patients with CVD, some limitations, including drug complications, still exist. Hence, the endocannabinoid system (ECS) was proposed as a new avenue for CVDs treatment. The ECS components are widely distributed through the body, including the heart and blood vessels, thus the action of its endogenous and exogenous ligands, in particular, phytocannabinoids play a key role in various pathological states. The cardiovascular action of cannabinoids is complex as they affect vasculature and myocardium directly via specific receptors and exert indirect effects through the central and peripheral nervous system. The growing interest in phytocannabinoid studies, however, has extended the knowledge about their molecular targets as well as therapeutical properties; nonetheless, some areas of their actions are not yet fully recognized. Researchers have reported various cannabinoids, especially cannabidiol, as a promising approach to CVDs; hence, the purpose of this review is to summarize and update the cardiovascular actions of the most potent phytocannabinoids and the potential therapeutic role of ECS in CVDs, including ischemic reperfusion injury, arrhythmia, heart failure as well as hypertension.

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 Inhibits Multiple Ion Channels in Rabbit Ventricular Cardiomyocytes

Cannabidiol (CBD), a major non-psychotropic cannabinoid found in the Cannabis plant, has been shown to exert anti-nociceptive, anti-psychotic, and anti-convulsant effects and to also influence the cardiovascular system. In this study, the effects of CBD on major ion currents were investigated using the patch-clamp technique in rabbit ventricular myocytes. CBD inhibited voltage-gated Na⁺ and Ca²⁺ channels with IC₅₀ values of 5.4 and 4.8 µM, respectively. In addition, CBD, at lower concentrations, suppressed ion currents mediated by rapidly and slowly activated delayed rectifier K⁺ channels with IC₅₀ of 2.4 and 2.1 µM, respectively. CBD, up to 10 μM, did not have any significant effect on inward rectifier I_K1 and transient outward I_to currents. The effects of CBD on these currents developed gradually, reaching steady-state levels within 5–8 min, and recoveries were usually slow and partial. Hill coefficients higher than unity in concentration-inhibition curves suggested multiple CBD binding sites on these channels. These findings indicate that CBD affects cardiac electrophysiology by acting on a diverse range of ion channels and suggest that caution should be exercised when CBD is administered to carriers of cardiac channelopathies or to individuals using drugs known to affect the rhythm or the contractility of the heart.

The Endocannabinoid System and Cannabidiol: Past, Present, and Prospective for Cardiovascular Diseases

In the past, cannabis was commonly associated with mysticism and illegality. Fortunately, in recent years perspectives and discourses have changed. More prominence has been given to the rigorous scientific effort that led to the discovery of cannabis' many physiological actions and endogenous signalling mechanisms. The endocannabinoid system is a complex and heterogeneous pro-homeostatic network comprising different receptors with several endogenous ligands, numerous metabolic enzymes and regulatory proteins. Therefore, it is not surprising that alterations and dysfunctions of the endocannabinoid system are observed in almost every category of disease. Such high degree of pathophysiological involvement suggests the endocannabinoid system is a promising therapeutic target and prompted the translation of resurgent scientific findings into clinical therapies. Shifting attitudes toward cannabis also raised other matters such as increased patient awareness, prescription requests, self-medication, recreational use, recognition of new knowledge gaps, renewed scientific activity, and seemingly exponential growth of the cannabis industry. This review, following a general overview of cannabis and the endocannabinoid system, assiduously describes its role within the context of cardiovascular diseases, paying particular attention to the Janus influence that endocannabinoid system modulators can have on the cardiovascular system.

Cannabidiol-mediated RISK PI3K/AKT and MAPK/ERK pathways decreasing reperfusion myocardial damage

Myocardial ischemia continues to be the first cause of morbimortality in the world; the definitive treatment is reperfusion; however, this action causes additional damage to ischemic myocardial tissue; this forces to seek therapies of cardioprotection to reduce this additional damage. There are many cardioprotective agents; within these, cannabinoids have shown to have beneficial effects, mainly cannabidiol (CBD). CBD is a non psychoactive cannabinoid. To evaluate the effect in experimental models of CBD in myocardial ischemia reperfusion in rats, twelve-week-old male rats have been used. The animals were divides in 3 groups: control(C), ischemia reperfusion (IR) and CBD pretreatment (1/day/5mg/kg /10days). Langendorff organ isolate studies were performed, and the area of infarction was assessed with triphenyl tetrazolium, in addition to molecular analysis of AT1 and AT2 receptors and Akt and Erk proteins and their phosphorylated forms related to RISK pathways. It was observed that there is an improvement with the use of CBD increasing inotropism and cardiac lusitropism, improving considerably the cardiovascular functionality. These could be related to the reduction of the area of infarction and activation of the AT2 receptor and the RISK pathway with absence of activation of the AT2 receptor (these could relate the reduction of the infarct area and the restoration of cardiovascular function with the activation of the AT2 receptor and the RISK pathway with the absence of activation of the AT2 receptor). The use of cannabinoids was shown to have beneficial effects when used as a treatment for myocardial reperfusion damage.

A molecular explanation of cardiovascular protection through abnormal cannabidiol: Involving the dysfunctional β-adrenergic and ATP-sensitive K+ channel activity in cardiovascular compromised preterm infants

Growing cannabis efficacy, usage frequency, legal supply, and declining awareness of danger recently led to expanded United States cannabis exposure. In turn, cannabis use among elderly people over 50 has more than tripled in a decade and has contributed toward a positive association of cannabis use with pathological conditions, which include type II diabetes, metabolic syndrome, neurovascular and cardiovascular disease. Remarkably, all these outcome results are mediated by the involvement of the ATP-sensitive K+ channel. Cardiovascular compromise is a common syndrome in preterm infants that leads to incidence and death and has been distinguished by poor systemic flow or hypotension. Conditions of cardiovascular compromise include vasodysregulation and myocardial malfunction through dysfunctional β-adrenergic activity. To avoid organ hypoperfusion progressing to tissue hypoxia-ischemia, inotropic drugs are used. Many premature children, however, respond insufficiently to inotropic activity with adrenergic agonists. The clinical disturbance including myocardial dysfunction through the activation of the ATP-sensitive K+ channel is often involved and the comparative efficacy of the nonpsychotropic cannabinoid, abnormal cannabidiol (Abn-CBD) is not yet known. Therefore, our primary aim was to investigate the molecular exploration of the cannabinoid system specifically Abn-CBD in cardiovascular protection involving dysregulated KATP.

Haematopoietic and cardiac GPR55 synchronize post-myocardial infarction remodelling

While classical cannabinoid receptors are known to crucially impact on myocardial infarction (MI) repair, a function of the cannabinoid-sensitive receptor GPR55 herein is poorly understood. We investigated the role of GPR55 in cardiac physiology and post-MI inflammation and remodelling. Global GPR55-/- and wildtype (WT) mice were basally characterized or assigned to 1, 3 or 28 days permanent MI and subsequently analysed via pro-inflammatory and pro-hypertrophic parameters. GPR55-/- deficiency was basally associated with bradycardia, increased diastolic LV volume and sarcomere length and a subtle inflammatory phenotype. While infarct size and myeloid cell infiltration were unaffected by GPR55 depletion, acute cardiac chemokine production was prolonged post-MI. Concurrently, GPR55-/- hearts exhibited a premature expansion of pro-reparative and phagocytic macrophages paralleled by early up-regulation of extracellular matrix (ECM) factors 3 days post-MI, which could be mimicked by sole haematopoietic GPR55 depletion. Moreover, global GPR55 deficiency mitigated MI-induced foetal gene re-programming and cardiomyocyte hypertrophy, culminating in aggravated LV dilatation and infarct expansion. GPR55 regulates cardiac homeostasis and ischaemia responses by maintaining adequate LV filling and modulating three crucial processes post-MI: wound healing kinetics, cardiomyocyte hypertrophy and maladaptive remodelling.

The Yin and Yang of Cannabis: A Systematic Review of Human Neuroimaging Evidence of the Differential Effects of Δ9-Tetrahydrocannabinol and Cannabidiol

Cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) have been the most investigated cannabinoids at the human and preclinical levels, although the neurobiological mechanisms underlying their effects remain unclear. Human experimental evidence complemented by observational studies suggests that THC may have psychotogenic effects while CBD may have antipsychotic effects. However, whether their effects on brain function are consistent with their opposing behavioral effects remains unclear. To address this, here we synthesize neuroimaging evidence investigating the acute effects of THC and CBD on human brain function using a range of neuroimaging techniques, with an aim to identify the key brain substrates where THC and CBD have opposing effects. After a systematic search, a review of the available studies indicated marked heterogeneity. However, an overall pattern of opposite effect profiles of the two cannabinoids was evident with some degree of consistency, primarily attributed to the head-to-head challenge studies of THC and CBD. While head-to-head comparisons are relatively few, collectively the evidence suggests that opposite effects of THC and CBD may be present in the striatum, parahippocampus, anterior cingulate/medial prefrontal cortex, and amygdala, with opposite effects less consistently identified in other regions. Broadly, THC seems to increase brain activation and blood flow, whereas CBD seems to decrease brain activation and blood flow. Given the sparse evidence, there is a particular need to understand the mechanisms underlying their opposite behavioral effects because it may not only offer insights into the underlying pathophysiological mechanisms of psychotic disorders but also suggest potentially novel targets and biomarkers for drug discovery.

Opportunities, Challenges and Pitfalls of Using Cannabidiol as an Adjuvant Drug in COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may lead to coronavirus disease 2019 (COVID-19) which, in turn, may be associated with multiple organ dysfunction. In this review, we present advantages and disadvantages of cannabidiol (CBD), a non-intoxicating phytocannabinoid from the cannabis plant, as a potential agent for the treatment of COVID-19. CBD has been shown to downregulate proteins responsible for viral entry and to inhibit SARS-CoV-2 replication. Preclinical studies have demonstrated its effectiveness against diseases of the respiratory system as well as its cardioprotective, nephroprotective, hepatoprotective, neuroprotective and anti-convulsant properties, that is, effects that may be beneficial for COVID-19. Only the latter two properties have been demonstrated in clinical studies, which also revealed anxiolytic and antinociceptive effects of CBD (given alone or together with Δ9-tetrahydrocannabinol), which may be important for an adjuvant treatment to improve the quality of life in patients with COVID-19 and to limit post-traumatic stress symptoms. However, one should be aware of side effects of CBD (which are rarely serious), drug interactions (also extending to drugs acting against COVID-19) and the proper route of its administration (vaping may be dangerous). Clearly, further clinical studies are necessary to prove the suitability of CBD for the treatment of COVID-19.

Chronic cannabidiol treatment reduces the carbachol-induced coronary constriction and left ventricular cardiomyocyte width of the isolated hypertensive rat heart

Cannabidiol (CBD) is suggested to possess cardioprotective properties. We examined the influence of chronic (10 mg/kg once daily for 2 weeks) CBD administration on heart structure (e.g. cardiomyocyte width) and function (e.g. stimulatory and inhibitory responses induced by β-adrenoceptor (isoprenaline) and muscarinic receptor (carbachol) activation, respectively). Experiments were performed on hearts and/or left atria isolated from spontaneously (SHR) and deoxycorticosterone (DOCA-salt) hypertensive rats; Wistar-Kyoto (WKY) and sham-operated rats (SHAM) served as the respective normotensive controls. CBD diminished the width of cardiomyocytes in left ventricle and reduced the carbachol-induced vasoconstriction of coronary arteries both in DOCA-salt and SHR. However, it failed to affect left ventricular hypertrophy and even aggravated the impaired positive and negative lusitropic effects elicited by isoprenaline and carbachol, respectively. In normotensive hearts CBD led to untoward structural and functional effects, which occurred only in WKY or SHAM or, like the decrease in β1-adrenoceptor density, in either control strain. In conclusion, due to its modest beneficial effect in hypertension and its adverse effects in normotensive hearts, caution should be taken when using CBD as a drug in therapy.

Cannabis sativa extracts protect LDL from Cu2+-mediated oxidation

Background

Multiple therapeutic properties have been attributed to Cannabis sativa. However, further research is required to unveil the medicinal potential of Cannabis and the relationship between biological activity and chemical profile.

Objectives

The primary objective of this study was to characterize the chemical profile and antioxidant properties of three varieties of Cannabis sativa available in Uruguay during progressive stages of maturation.

Methods

Fresh samples of female inflorescences from three stable Cannabis sativa phenotypes, collected at different time points during the end of the flowering period were analyzed. Chemical characterization of chloroform extracts was performed by ¹H-NMR. The antioxidant properties of the cannabis sativa extracts, and pure cannabinoids, were measured in a Cu²⁺-induced LDL oxidation assay.

Results

The main cannabinoids in the youngest inflorescences were tetrahydrocannabinolic acid (THC-A, 242 ± 62 mg/g) and tetrahydrocannabinol (THC, 7.3 ± 6.5 mg/g). Cannabinoid levels increased more than twice in two of the mature samples. A third sample showed a lower and constant concentration of THC-A and THC (177 ± 25 and 1 ± 1, respectively). The THC-A/THC rich cannabis extracts increased the latency phase of LDL oxidation by a factor of 1.2-3.5 per μg, and slowed down the propagation phase of lipoperoxidation (IC₅₀ 1.7-4.6 μg/mL). Hemp, a cannabidiol (CBD, 198 mg/g) and cannabidiolic acid (CBD-A, 92 mg/g) rich variety, also prevented the formation of conjugated dienes during LDL oxidation. In fact, 1 μg of extract was able to stretch the latency phase 3.7 times and also to significantly reduce the steepness of the propagation phase (IC₅₀ of 8 μg/mL). Synthetic THC lengthened the duration of the lag phase by a factor of 21 per μg, while for the propagation phase showed an IC₅₀ ≤ 1 μg/mL. Conversely, THC-A was unable to improve any parameter. Meanwhile, the presence of 1 μg of pure CBD and CBD-A increased the initial latency phase 4.8 and 9.4 times, respectively, but did not have an effect on the propagation phase.

Conclusion

Cannabis whole extracts acted on both phases of lipid oxidation in copper challenged LDL. Those effects were just partially related with the content of cannabinoids and partially recapitulated by isolated pure cannabinoids. Our results support the potentially beneficial effects of cannabis sativa whole extracts on the initial phase of atherosclerosis.

Therapeutic Applications of Cannabinoids in Cardiomyopathy and Heart Failure

A large number of cannabinoids have been discovered that could play a role in mitigating cardiac affections. However, none of them has been as widely studied as cannabidiol (CBD), most likely because, individually, the others offer only partial effects or can activate potential harmful pathways. In this regard, CBD has proven to be of great value as a cardioprotective agent since it is a potent antioxidant and anti-inflammatory molecule. Thus, we conducted a review to condensate the currently available knowledge on CBD as a therapy for different experimental models of cardiomyopathies and heart failure to detect the molecular pathways involved in cardiac protection. CBD therapy can greatly limit the production of oxygen/nitrogen reactive species, thereby limiting cellular damage, protecting mitochondria, avoiding caspase activation, and regulating ionic homeostasis. Hence, it can affect myocardial contraction by restricting the activation of inflammatory pathways and cytokine secretion, lowering tissular infiltration by immune cells, and reducing the area of infarct and fibrosis formation. These effects are mediated by the activation or inhibition of different receptors and target molecules of the endocannabinoid system. In the final part of this review, we explore the current state of CBD in clinical trials as a treatment for cardiovascular diseases and provide evidence of its potential benefits in humans.

Cannabinoids in Metabolic Syndrome and Cardiac Fibrosis

PURPOSE OF REVIEW

This article provides a concise overview of how cannabinoids and the endocannabinoid system (ECS) have significant implications for the prevention and treatment of metabolic syndrome (MetS) and for the treatment of cardiovascular disorders, including cardiac fibrosis.

RECENT FINDINGS

Over the past few years, the ECS has emerged as a pivotal component of the homeostatic mechanisms for the regulation of many bodily functions, including inflammation, digestion, and energy metabolism. Therefore, the pharmacological modulation of the ECS by cannabinoids represents a novel strategy for the management of many diseases. Specifically, increasing evidence from preclinical research studies has opened new avenues for the development of cannabinoid-based therapies for the management and potential treatment of MetS and cardiovascular diseases. Current information indicates that modulation of the ECS can help maintain overall health and well-being due to its homeostatic function. From a therapeutic perspective, cannabinoids and the ECS have also been shown to play a key role in modulating pathophysiological states such as inflammatory, neurodegenerative, gastrointestinal, metabolic, and cardiovascular diseases, as well as cancer and pain. Thus, targeting and modulating the ECS with cannabinoids or cannabinoid derivatives may represent a major disease-modifying medical advancement to achieve successful treatment for MetS and certain cardiovascular diseases.

The positive and negative cardiovascular effects of cannabis

INTRODUCTION

The use of cannabis and its derivatives have increased steadily over the past few decades, prompting patients and clinicians to increasingly inquire about its health effects and safety profile. However, despite promising evidence suggesting therapeutic utilization, cannabis remains a controlled substance in most countries and is largely considered to have no medical or recreational benefit; thus, a lack of observational studies and randomized control trials exist to outline positive and negative health implications. Ultimately, this leaves patients, health-care professionals, and policymakers without necessary evidence required to make informed decisions on cannabis use.

AREAS COVERED

This review outlines cannabis in a clinical setting and delves into specific effects of cannabinoids on cardiovascular health and disease. It discusses positive and negative health implications associated with cannabis, mechanisms in cardiovascular disease, and reveals methods guiding cannabis use in the clinical setting.

EXPERT OPINION

Advances in research are necessary to guide decisions regarding cannabinoid use. Countries that have federally legalized cannabis have a unique opportunity to study cardiovascular implications in an unbiased and comprehensive manner. Ultimately, as cannabis use will inevitably increase, researchers, clinicians, and policymakers must work together to ensure cannabis is utilized in a way that is therapeutically beneficial.

Cannabidiol Ameliorates Monocrotaline-Induced Pulmonary Hypertension in Rats

Cannabidiol (CBD) is known for its vasorelaxant (including in the human pulmonary artery), anti-proliferative and anti-inflammatory properties. The aim of our study was to examine the potential preventive effect of chronic CBD administration (10 mg/kg/day for three weeks) on monocrotaline (MCT)-induced pulmonary hypertension (PH) rats. PH was connected with elevation of right ventricular systolic pressure; right ventricle hypertrophy; lung edema; pulmonary artery remodeling; enhancement of the vasoconstrictor and decreasing vasodilatory responses; increases in plasma concentrations of tissue plasminogen activator, plasminogen activator inhibitor type 1 and leukocyte count; and a decrease in blood oxygen saturation. CBD improved all abovementioned changes induced by PH except right ventricle hypertrophy and lung edema. In addition, CBD increased lung levels of some endocannabinoids (anandamide, N-arachidonoyl glycine, linolenoyl ethanolamide, palmitoleoyl ethanolamide and eicosapentaenoyl ethanolamide but not 2-arachidonoylglycerol). CBD did not affect the cardiopulmonary system of control rats or other parameters of blood morphology in PH. Our data suggest that CBD ameliorates MCT-induced PH in rats by improving endothelial efficiency and function, normalization of hemostatic alterations and reduction of enhanced leukocyte count determined in PH. In conclusion, CBD may be a safe, promising therapeutic or adjuvant therapy agent for the treatment of human pulmonary artery hypertension.

The Effects of Cannabidiol, a Non-Intoxicating Compound of Cannabis, on the Cardiovascular System in Health and Disease

Cannabidiol (CBD) is a non-intoxicating and generally well-tolerated constituent of cannabis which exhibits potential beneficial properties in a wide range of diseases, including cardiovascular disorders. Due to its complex mechanism of action, CBD may affect the cardiovascular system in different ways. Thus, we reviewed the influence of CBD on this system in health and disease to determine the potential risk of cardiovascular side effects during CBD use for medical and wellness purposes and to elucidate its therapeutic potential in cardiovascular diseases. Administration of CBD to healthy volunteers or animals usually does not markedly affect hemodynamic parameters. Although CBD has been found to exhibit vasodilatory and antioxidant properties in hypertension, it has not affected blood pressure in hypertensive animals. Hypotensive action of CBD has been mainly revealed under stress conditions. Many positive effects of CBD have been observed in experimental models of heart diseases (myocardial infarction, cardiomyopathy, myocarditis), stroke, neonatal hypoxic ischemic encephalopathy, sepsis-related encephalitis, cardiovascular complications of diabetes, and ischemia/reperfusion injures of liver and kidneys. In these pathological conditions CBD decreased organ damage and dysfunction, oxidative and nitrative stress, inflammatory processes and apoptosis, among others. Nevertheless, further clinical research is needed to recommend the use of CBD in the treatment of cardiovascular diseases.

Cannabidiol and Sports Performance: a Narrative Review of Relevant Evidence and Recommendations for Future Research

Cannabidiol (CBD) is a non-intoxicating cannabinoid derived from Cannabis sativa. CBD initially drew scientific interest due to its anticonvulsant properties but increasing evidence of other therapeutic effects has attracted the attention of additional clinical and non-clinical populations, including athletes. Unlike the intoxicating cannabinoid, Δ9-tetrahydrocannabinol (Δ9-THC), CBD is no longer prohibited by the World Anti-Doping Agency and appears to be safe and well-tolerated in humans. It has also become readily available in many countries with the introduction of over-the-counter "nutraceutical" products. The aim of this narrative review was to explore various physiological and psychological effects of CBD that may be relevant to the sport and/or exercise context and to identify key areas for future research. As direct studies of CBD and sports performance are is currently lacking, evidence for this narrative review was sourced from preclinical studies and a limited number of clinical trials in non-athlete populations. Preclinical studies have observed robust anti-inflammatory, neuroprotective and analgesic effects of CBD in animal models. Preliminary preclinical evidence also suggests that CBD may protect against gastrointestinal damage associated with inflammation and promote healing of traumatic skeletal injuries. However, further research is required to confirm these observations. Early stage clinical studies suggest that CBD may be anxiolytic in "stress-inducing" situations and in individuals with anxiety disorders. While some case reports indicate that CBD improves sleep, robust evidence is currently lacking. Cognitive function and thermoregulation appear to be unaffected by CBD while effects on food intake, metabolic function, cardiovascular function, and infection require further study. CBD may exert a number of physiological, biochemical, and psychological effects with the potential to benefit athletes. However, well controlled, studies in athlete populations are required before definitive conclusions can be reached regarding the utility of CBD in supporting athletic performance.

The effects of acute and sustained cannabidiol dosing for seven days on the haemodynamics in healthy men: A randomised controlled trial

BACKGROUND

In vivo studies show that cannabidiol (CBD) acutely reduces blood pressure (BP) in men. The aim of this study was to assess the effects of repeated CBD dosing on haemodynamics.

METHODS

Twenty-six healthy males were given CBD (600 mg) or placebo orally for seven days in a randomised, placebo-controlled, double-blind, parallel study (n = 13/group). Cardiovascular parameters were assessed at rest and in response to isometric exercise after acute and repeated dosing using Finometer®, Vicorder® and Duplex ultrasound.

RESULTS

Compared to placebo, CBD significantly reduced resting mean arterial pressure (P = .04, two-way ANOVA, mean difference (MD) -2 mmHg, 95% CI -3.6 to -0.3) after acute dosing, but not after repeated dosing. In response to stress, volunteers who had taken CBD had lower systolic BP after acute (P = .001, two-way ANOVA, MD -6 mmHg, 95% CI -10 to -1) and repeated (P = .02, two-way ANOVA, MD -5.7 mmHg, 95% CI -10 to -1) dosing. Seven days of CBD increased internal carotid artery diameter (MD +0.55 mm, P = .01). Within the CBD group, repeated dosing reduced arterial stiffness by day 7 (pulse wave velocity; MD -0.44 m/s, P = .05) and improved endothelial function (flow mediation dilatation, MD +3.5%, P = .02, n = 6 per group), compared to day 1.

CONCLUSION

CBD reduces BP at rest after a single dose but the effect is lost after seven days of treatment (tolerance); however, BP reduction during stress persists. The reduction in arterial stiffness and improvements in endothelial function after repeated CBD dosing are findings that warrant further investigation in populations with vascular diseases.

Targeting GPCRs Against Cardiotoxicity Induced by Anticancer Treatments

Novel anticancer medicines, including targeted therapies and immune checkpoint inhibitors, have greatly improved the management of cancers. However, both conventional and new anticancer treatments induce cardiac adverse effects, which remain a critical issue in clinic. Cardiotoxicity induced by anti-cancer treatments compromise vasospastic and thromboembolic ischemia, dysrhythmia, hypertension, myocarditis, and cardiac dysfunction that can result in heart failure. Importantly, none of the strategies to prevent cardiotoxicity from anticancer therapies is completely safe and satisfactory. Certain clinically used cardioprotective drugs can even contribute to cancer induction. Since G protein coupled receptors (GPCRs) are target of forty percent of clinically used drugs, here we discuss the newly identified cardioprotective agents that bind GPCRs of adrenalin, adenosine, melatonin, ghrelin, galanin, apelin, prokineticin and cannabidiol. We hope to provoke further drug development studies considering these GPCRs as potential targets to be translated to treatment of human heart failure induced by anticancer drugs.

The Protective Mechanism of Cannabidiol in Cardiac Injury: A Systematic Review of Non-Clinical Studies

Background:

Cardiac disease is accounted as the leading cause of worldwide morbidity and mortality. The disease is characterized by the overproduction of reactive oxygen and/or nitrogen species (ROS/RNS), and induction of oxidative stress. Cannabidiol (CBD) is a non-psychoactive ingredient of marijuana that has been reported to be safe and well tolerated in patients. Due to its pleiotropic effect, CBD has been shown to exert cytoprotective effects. This study intended to clarify the mechanisms and the potential role of CBD regarding cardiac injuries treatment.

Methods:

A systematic literature search was conducted, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, in the electronic databases including PubMed, Web of Science, Scopus, and Embase up to June 2019 using predefined search terms in the titles and abstracts. Accordingly, a set of pre-specified inclusion and exclusion criteria were considered and 8 articles were ultimately included in this study.

Results:

Our findings demonstrate that CBD has multi-functional protective assets to improve cardiac injuries; preliminary through scavenging of free radicals, and reduction of oxidative stress, apoptosis, and inflammation.

Conclusion:

CBD can protect against cardiac injuries, mainly through its antioxidative and antiapoptotic effects on the basis of non-clinical studies. The cardioprotective effects of the CBD need to be further studied in welldesigned clinical trials.

l-α-Lysophosphatidylinositol (LPI) aggravates myocardial ischemia/reperfusion injury via a GPR55/ROCK-dependent pathway

The phospholipid l-α-lysophosphatidylinositol (LPI), an endogenous ligand for GPR55, is elevated in patients with acute coronary syndrome, and a GPR55 antagonist cannabidiol (CBD) reduces experimental ischemia/reperfusion (I/R) injury. While LPI activates multiple signaling pathways, little is known about which ones are important in cardiomyocytes. In this study we explored whether activation of the Rho kinase/ROCK/p38 MAPK pathway is responsible for LPI-induced extension of I/R injury. Using a high-throughput screening method (dynamic mass redistribution; DMR), mouse- and human-induced pluripotent stem cell (iPSC) cardiomyocytes exposed to LPI were shown to exhibit a rapid, sustained, and concentration-dependent (1 nmol L-1-30 μmol L-1) cellular response. Y-27632 (ROCK inhibitor; 10 & 50 μmol L-1) and CBD (1 μmol L-1) both abolished the DMR response to LPI (10 μmol L-1). In murine iPSC cardiomyocytes, LPI-induced ROCK and p38 MAPK phosphorylation, both of which were prevented by Y-27632 and CBD, but did not induce JNK activation or cleavage of caspase-3. In hearts isolated from wild type (WT) mice subjected to 30 minutes global I/R, LPI (10 μmol L-1) administered via the coronary circulation increased infarct size when applied prior to ischemia onset, but not when given at the time of reperfusion. The exacerbation of tissue injury by LPI was not seen in hearts from GPR55-/- mice or in the presence of Y-27632, confirming that injury is mediated via the GPR55/ROCK/p38 MAPK pathway. These findings suggest that raised levels of LPI in the vicinity of a developing infarct may worsen the outcome of AMI.

Editor's Choice- Reperfusion cardiac arrhythmias and their relation to reperfusion-induced cell death

Reperfusion does not only salvage ischaemic myocardium but can also cause additional cell death which is called lethal reperfusion injury. The time of reperfusion is often accompanied by ventricular arrhythmias, i.e. reperfusion arrhythmias. While both conditions are seen as separate processes, recent research has shown that reperfusion arrhythmias are related to larger infarct size. The pathophysiology of fatal reperfusion injury revolves around intracellular calcium overload and reactive oxidative species inducing apoptosis by opening of the mitochondrial protein transition pore. The pathophysiological basis for reperfusion arrhythmias is the same intracellular calcium overload as that causing fatal reperfusion injury. Therefore both conditions should not be seen as separate entities but as one and the same process resulting in two different visible effects. Reperfusion arrhythmias could therefore be seen as a potential marker for fatal reperfusion injury.

Therapeutic applications of cannabinoids

The psychoactive property of cannabinoids is well known and there has been a continuous controversy regarding the usage of these compounds for therapeutic purposes all over the world. Their use for medical and research purposes are restricted in various countries. However, their utility as medications should not be overshadowed by its negative physiological activities. This review article is focused on the therapeutic potential and applications of phytocannabinoids and endocannabinoids. We further highlights their mode of action, overall effects on physiology, various in vitro and in vivo studies that have been done so far and the extent to which these compounds can be useful in different disease conditions such as cancer, Alzheimer's disease, multiple sclerosis, pain, inflammation, glaucoma and many others. Thus, this work is an attempt to make the readers understand the positive implications of these compounds and indicates the significant developments of utilizing cannabinoids as therapeutic agents.

A single dose of cannabidiol reduces blood pressure in healthy volunteers in a randomized crossover study

BACKGROUND

Cannabidiol (CBD) is a nonpsychoactive phytocannabinoid used in multiple sclerosis and intractable epilepsies. Preclinical studies show CBD has numerous cardiovascular benefits, including a reduced blood pressure (BP) response to stress. The aim of this study was to investigate if CBD reduces BP in humans.

METHODS

Nine healthy male volunteers were given 600 mg of CBD or placebo in a randomized, placebo-controlled, double-blind, crossover study. Cardiovascular parameters were monitored using a finometer and laser Doppler.

RESULTS

CBD reduced resting systolic BP (-6 mmHg; P < 0.05) and stroke volume (-8 ml; P < 0.05), with increased heart rate (HR) and maintained cardiac output. Subjects who had taken CBD had lower BP (-5 mmHg; P < 0.05, especially before and after stress), increased HR (+10 bpm; P < 0.01), decreased stroke volume (-13 ml; P < 0.01), and a blunted forearm skin blood flow response to isometric exercise. In response to cold stress, subjects who had taken CBD had blunted BP (-6 mmHg; P < 0.01) and increased HR (+7 bpm; P < 0.05), with lower total peripheral resistance.

CONCLUSIONS

This data shows that acute administration of CBD reduces resting BP and the BP increase to stress in humans, associated with increased HR. These hemodynamic changes should be considered for people taking CBD. Further research is required to establish whether CBD has a role in the treatment of cardiovascular disorders.

A Systematic Review and Meta-Analysis of the Haemodynamic Effects of Cannabidiol

Despite cannabidiol (CBD) having numerous cardiovascular effects in vitro, its haemodynamic effects in vivo are unclear. Nonetheless, the clinical use of CBD (Epidiolex) is becoming more widespread. The aim of this systematic review was to establish whether CBD is associated with changes in haemodynamics in vivo. Twenty-five studies that assessed the haemodynamic effects of CBD (from PubMed, Medline and EMBASE) were systematically reviewed and meta-analyzed. Data on blood pressure (BP), heart rate (HR), and blood flow (BF) were extracted and analyzed using random effects models. Twenty-two publications assessed BP and HR among 6 species (BP n = 344 and HR n = 395), and 5 publications assessed BF in 3 species (n = 56) after acute dosing of CBD. Chronic dosing was assessed in 4 publications in 3 species (total subjects BP, n = 6; HR, n = 27; BF, n = 3). Acute CBD dosing had no effect on BP or HR under control conditions. Similarly, chronic dosing with CBD had no effect on HR. In models of stress, acute CBD administration significantly reduced the increase in BP and HR induced by stress (BP, mean difference (MD) −3.54, 95% CI −5.19, −1.9, p < 0.0001; HR, MD −16.23, 95% CI −26.44, −6.02, p = 0.002). In mouse models of stroke, CBD significantly increased cerebral blood flow (CBF, standardized mean difference (SMD) 1.62, 95% CI 0.41, 2.83, p = 0.009). Heterogeneity among the studies was present, there was no publication bias except in HR of control and stressful conditions after acute CBD dosing, and median study quality was 5 out of 9 (ranging from 1 to 8). From the limited data available, we conclude that acute and chronic administration of CBD had no effect on BP or HR under control conditions, but reduces BP and HR in stressful conditions, and increases cerebral blood flow (CBF) in mouse models of stroke. Further studies are required to fully understand the potential haemodynamic effects of CBD in humans under normal and pathological conditions.

Cannabidiol: State of the art and new challenges for therapeutic applications

Over the past years, several lines of evidence support a therapeutic potential of Cannabis derivatives and in particular phytocannabinoids. Δ⁹-THC and cannabidiol (CBD) are the most abundant phytocannabinoids in Cannabis plants and therapeutic application for both compounds have been suggested. However, CBD is recently emerging as a therapeutic agent in numerous pathological conditions since devoid of the psychoactive side effects exhibited instead by Δ⁹-THC. In this review, we highlight the pharmacological activities of CBD, its cannabinoid receptor-dependent and -independent action, its biological effects focusing on immunomodulation, angiogenetic properties, and modulation of neuronal and cardiovascular function. Furthermore, the therapeutic potential of cannabidiol is also highlighted, in particular in nuerological diseases and cancer.

From Phytocannabinoids to Cannabinoid Receptors and Endocannabinoids: Pleiotropic Physiological and Pathological Roles Through Complex Pharmacology

Apart from having been used and misused for at least four millennia for, among others, recreational and medicinal purposes, the cannabis plant and its most peculiar chemical components, the plant cannabinoids (phytocannabinoids), have the merit to have led humanity to discover one of the most intriguing and pleiotropic endogenous signaling systems, the endocannabinoid system (ECS). This review article aims to describe and critically discuss, in the most comprehensive possible manner, the multifaceted aspects of 1) the pharmacology and potential impact on mammalian physiology of all major phytocannabinoids, and not only of the most famous one Δ9-tetrahydrocannabinol, and 2) the adaptive pro-homeostatic physiological, or maladaptive pathological, roles of the ECS in mammalian cells, tissues, and organs. In doing so, we have respected the chronological order of the milestones of the millennial route from medicinal/recreational cannabis to the ECS and beyond, as it is now clear that some of the early steps in this long path, which were originally neglected, are becoming important again. The emerging picture is rather complex, but still supports the belief that more important discoveries on human physiology, and new therapies, might come in the future from new knowledge in this field.

Prenatal cannabis exposure - The "first hit" to the endocannabinoid system

As more states and countries legalize medical and/or adult recreational marijuana use, the incidences of prenatal cannabis exposure (PCE) will likely increase. While young people increasingly view marijuana as innocuous, marijuana preparations have been growing in potency in recent years, potentially creating global clinical, public health, and workforce concerns. Unlike fetal alcohol spectrum disorder, there is no phenotypic syndrome associated with PCE. There is also no preponderance of evidence that PCE causes lifelong cognitive, behavioral, or functional abnormalities, and/or susceptibility to subsequent addiction. However, there is compelling circumstantial evidence, based on the principles of teratology and fetal malprogramming, suggesting that pregnant women should refrain from smoking marijuana. The usage of marijuana during pregnancy perturbs the fetal endogenous cannabinoid signaling system (ECSS), which is present and active from the early embryonic stage, modulating neurodevelopment and continuing this role into adulthood. The ECSS is present in virtually every brain structure and organ system, and there is also evidence that this system is important in the regulation of cardiovascular processes. Endocannabinoids (eCBs) undergird a broad spectrum of processes, including the early stages of fetal neurodevelopment and uterine implantation. Delta-9-tetrahydrocannabinol (THC), the psychoactive chemical in cannabis, enters maternal circulation, and readily crosses the placental membrane. THC binds to CB receptors of the fetal ECSS, altering neurodevelopment and possibly rewiring ECSS circuitry. In this review, we discuss the Double-Hit Hypothesis as it relates to PCE. We contend that PCE, similar to a neurodevelopmental teratogen, delivers the first hit to the ECSS, which is compromised in such a way that a second hit (i.e., postnatal stressors) will precipitate the emergence of a specific phenotype. In summary, we conclude that perturbations of the intrauterine milieu via the introduction of exogenous CBs alter the fetal ECSS, predisposing the offspring to abnormalities in cognition and altered emotionality. Based on recent experimental evidence that we will review here, we argue that young women who become pregnant should immediately take a "pregnant pause" from using marijuana.

Pharmacologic Effects of Cannabidiol on Acute Reperfused Myocardial Infarction in Rabbits: Evaluated With 3.0T Cardiac Magnetic Resonance Imaging and Histopathology

Cannabidiol (CBD) has anti-inflammatory effects. We explored its therapeutic effects on cardiac ischemia-reperfusion injury with an experimental imaging platform. Reperfused acute myocardial infarction (AMI) was induced in rabbits with a 90-minute coronary artery occlusion followed by 24-hour reperfusion. Before reperfusion, rabbits received 2 intravenous doses of 100 μg/kg CBD (n = 10) or vehicle (control, n = 10). Evans blue was intravenously injected for later detection of the AMI core. Cardiac magnetic resonance imaging was performed to evaluate cardiac morphology and function. After euthanasia, blood troponin I (cTnI) was assessed, and the heart was excised and infused with multifunctional red iodized oil dye. The heart was sliced for digital radiography to quantify the perfusion density rate, area at risk (AAR), and myocardial salvage index, followed by histomorphologic staining. Compared with controls, CBD treatment improved systolic wall thickening (P < 0.05), significantly increased blood flow in the AAR (P < 0.05), significantly decreased microvascular obstruction (P < 0.05), increased the perfusion density rate by 1.7-fold, lowered the AMI core/AAR ratio (P < 0.05), and increased the myocardial salvage index (P < 0.05). These improvements were associated with reductions in serum cTnI, cardiac leukocyte infiltration, and myocellular apoptosis (P < 0.05). Thus, CBD therapy reduced AMI size and facilitated restoration of left ventricular function. We demonstrated that this experimental platform has potential theragnostic utility.

Cannabidiol causes endothelium-dependent vasorelaxation of human mesenteric arteries via CB1 activation

Aims

The protective effects of cannabidiol (CBD) have been widely shown in preclinical models and have translated into medicines for the treatment of multiple sclerosis and epilepsy. However, the direct vascular effects of CBD in humans are unknown.

Methods and results

Using wire myography, the vascular effects of CBD were assessed in human mesenteric arteries, and the mechanisms of action probed pharmacologically. CBD-induced intracellular signalling was characterized using human aortic endothelial cells (HAECs). CBD caused acute, non-recoverable vasorelaxation of human mesenteric arteries with an R_max of ∼40%. This was inhibited by cannabinoid receptor 1 (CB₁) receptor antagonists, desensitization of transient receptor potential channels using capsaicin, removal of the endothelium, and inhibition of potassium efflux. There was no role for cannabinoid receptor-2 (CB₂) receptor, peroxisome proliferator activated receptor (PPAR)γ, the novel endothelial cannabinoid receptor (CB_e), or cyclooxygenase. CBD-induced vasorelaxation was blunted in males, and in patients with type 2 diabetes or hypercholesterolemia. In HAECs, CBD significantly reduced phosphorylated JNK, NFκB, p70s6 K and STAT5, and significantly increased phosphorylated CREB, ERK1/2, and Akt levels. CBD also increased phosphorylated eNOS (ser1177), which was correlated with increased levels of ERK1/2 and Akt levels. CB₁ receptor antagonism prevented the increase in eNOS phosphorylation.

Conclusion

This study shows, for the first time, that CBD causes vasorelaxation of human mesenteric arteries via activation of CB₁ and TRP channels, and is endothelium- and nitric oxide-dependent.

Effects of cannabidiol on contractions and calcium signaling in rat ventricular myocytes

Cannabidiol (CBD), a major nonpsychotropic cannabinoid found in Cannabis plant, has been shown to influence cardiovascular functions under various physiological and pathological conditions. In the present study, the effects of CBD on contractility and electrophysiological properties of rat ventricular myocytes were investigated. Video edge detection was used to measure myocyte shortening. Intracellular Ca(2+) was measured in cells loaded with the Ca(2+) sensitive fluorescent indicator fura-2 AM. Whole-cell patch clamp was used to measure action potential and Ca(2+) currents. Radioligand binding was employed to study pharmacological characteristics of CBD binding. CBD (1μM) caused a significant decrease in the amplitudes of electrically evoked myocyte shortening and Ca(2+) transients. However, the amplitudes of caffeine-evoked Ca(2+) transients and the rate of recovery of electrically evoked Ca(2+) transients following caffeine application were not altered. CBD (1μM) significantly decreased the duration of APs. Further studies on L-type Ca(2+) channels indicated that CBD inhibits these channels with IC50 of 0.1μM in a voltage-independent manner. Radioligand studies indicated that the specific binding of [(3)H]Isradipine, was not altered significantly by CBD. The results suggest that CBD depresses myocyte contractility by suppressing L-type Ca(2+) channels at a site different than dihydropyridine binding site and inhibits excitation-contraction coupling in cardiomyocytes.

An overview on development and application of an experimental platform for quantitative cardiac imaging research in rabbit models of myocardial infarction

To exploit the advantages of using rabbits for cardiac imaging research and to tackle the technical obstacles, efforts have been made under the framework of a doctoral research program. In this overview article, by cross-referencing the current literature, we summarize how we have developed a preclinical cardiac research platform based on modified models of reperfused myocardial infarction (MI) in rabbits; how the in vivo manifestations of cardiac imaging could be closely matched with those ex vivo macro- and microscopic findings; how these imaging outcomes could be quantitatively analyzed, validated and demonstrated; and how we could apply this cardiac imaging platform to provide possible solutions to certain lingering diagnostic and therapeutic problems in experimental cardiology. In particular, tissue components in acute cardiac ischemia have been stratified and characterized, post-infarct lipomatous metaplasia (LM) as a common but hardly illuminated clinical pathology has been identified in rabbit models, and a necrosis avid tracer as well as an anti-ischemic drug have been successfully assessed for their potential utilities in clinical cardiology. These outcomes may interest the researchers in the related fields and help strengthen translational research in cardiovascular diseases.

The effect of cannabidiol on ischemia/reperfusion-induced ventricular arrhythmias: the role of adenosine A1 receptors

Cannabidiol (CBD) is a nonpsychoactive phytocannabinoid with anti-inflammatory activity mediated by enhancing adenosine signaling. As the adenosine A1 receptor activation confers protection against ischemia/reperfusion (I/R)-induced ventricular arrhythmias, we hypothesized that CBD may have antiarrhythmic effect through the activation of adenosine A1 receptor. Cannabidiol has recently been shown to suppress ischemia-induced ventricular arrhythmias. We aimed to research the effect of CBD on the incidence and the duration of I/R-induced ventricular arrhythmias and to investigate the role of adenosine A1 receptor activation in the possible antiarrhythmic effect of CBD. Myocardial ischemia and reperfusion was induced in anesthetized male rats by ligating the left anterior descending coronary artery for 6 minutes and by loosening the bond at the coronary artery, respectively. Cannabidiol alone was given in a dose of 50 µg/kg, 10 minutes prior to coronary artery occlusion and coadministrated with adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) in a dose of 100 µg/kg, 15 minutes prior to coronary artery occlusion to investigate whether the antiarrhythmic effect of CBD is modified by the activation of adenosine A1 receptors. The experimental groups were as follows: (1) vehicle control (n = 10), (2) CBD (n = 9), (3) DPCPX (n = 7), and (4) CBD + DPCPX group (n = 7). Cannabidiol treatment significantly decreased the incidence and the duration of ventricular tachycardia, total length of arrhythmias, and the arrhythmia scores compared to control during the reperfusion period. The DPCPX treatment alone did not affect the incidence and the duration of any type of arrhythmias. However, DPCPX aborted the antiarrhythmic effect of CBD when it was combined with it. The present results demonstrated that CBD has an antiarrhythmic effect against I/R-induced arrhythmias, and the antiarrhythmic effect of CBD may be mediated through the activation of adenosine A1 receptor.

Feasibility of targeting ischaemia-related ventricular arrhythmias by mimicry of endogenous protection by endocannabinoids

BACKGROUND AND PURPOSE

The hypothesis that endocannabinoids protect hearts against ventricular fibrillation (VF) induced by myocardial ischaemia and reperfusion was examined, and the concept that cannabinoids may represent a new class of anti-VF drug was tested.

EXPERIMENTAL APPROACH

In rat isolated hearts (Langendorff perfusion), VF evoked by reperfusion after 60 min regional ischaemia is known to be exacerbated by inhibitors of endogenous protectants such as nitric oxide. This preparation was used to assay the effects of cannabinoid agonists and antagonists, and the protocols were varied to examine mechanisms.

KEY RESULTS

Reperfusion-induced VF was not facilitated by relatively selective CB1 (1 μM AM251) or CB2 (1 μM AM630) antagonists. VF evoked during early (30 min) acute ischaemia was also unaffected. However, AM251 significantly increased the incidence of VF and the duration of VF episodes occurring during the later stage of acute ischaemia (30-60 min). AM630 had no such effects. In a separate study, cannabinoid perfusion (anandamide or 2-arachidonoylglycerol, both 0.01-1 μM) failed to reduce VF incidence concentration-dependently during 30 min ischaemia. In all these studies, changes in ancillary variables (QT, PR, heart rate) were unrelated to changes in VF.

CONCLUSIONS AND IMPLICATIONS

Endocannabinoids are not endogenous anti-VF mediators during reperfusion, but may have a weak protective effect during the late stages of ischaemia, mediated via CB1 agonism. This does not suggest endocannabinoids are important endogenous protectants in these settings, or that CB1 (or CB2) receptors are useful novel targets for developing drugs for VF.

Protective effect of cannabidiol against cadmium hepatotoxicity in rats

The protective effect of cannabidiol, the non-psychoactive component of Cannabis sativa, against liver toxicity induced by a single dose of cadmium chloride (6.5 mgkg(-1) i.p.) was investigated in rats. Cannabidiol treatment (5 mgkg(-1)/day, i.p.) was applied for five days starting three days before cadmium administration. Cannabidiol significantly reduced serum alanine aminotransferase, and suppressed hepatic lipid peroxidation, prevented the depletion of reduced glutathione and nitric oxide, and catalase activity, and attenuated the elevation of cadmium level in the liver tissue resulted from cadmium administration. Histopathological examination showed that cadmium-induced liver tissue injury was ameliorated by cannabidiol treatment. Immunohistochemical analysis revealed that cannabidiol significantly decreased the cadmium-induced expression of tumor necrosis factor-α, cyclooxygenase-2, nuclear factor-κB, caspase-3, and caspase-9, and increased the expression of endothelial nitric oxide synthase in liver tissue. It was concluded that cannabidiol may represent a potential option to protect the liver tissue from the detrimental effects of cadmium toxicity.