Involvement of peripheral cannabinoid and opioid receptors in β-caryophyllene-induced antinociception

β-caryophyllene inhibits heroin self-administration, but does not alter opioid-induced antinociception in rodents

A growing body of research indicates that β-caryophyllene (BCP), a constituent present in a large number of plants, possesses significant therapeutic properties against CNS disorders, including alcohol and psychostimulant use disorders. However, it is unknown whether BCP has similar therapeutic potential for opioid use disorders. In this study, we found that systemic administration of BCP dose-dependently reduced heroin self-administration in rats under an FR2 schedule of reinforcement and partially blocked heroin-enhanced brain stimulation reward in DAT-cre mice, maintained by optical stimulation of midbrain dopamine neurons at high frequencies. Acute administration of BCP failed to block heroin conditioned place preference (CPP) in male mice, but attenuated heroin-induced CPP in females. Furthermore, repeated dosing with BCP for 5 days facilitated the extinction of CPP in female but not male mice. In the hot plate assay, pretreatment with the same doses of BCP failed to enhance or prolong opioid antinociception. Lastly, in a substitution test, BCP replacement for heroin failed to maintain intravenous BCP self-administration, suggesting that BCP itself has no reinforcing properties. These findings suggest that BCP may have certain therapeutic effects against opioid use disorders with fewer unwanted side-effects by itself.

Beta-caryophyllene in psychiatric and neurological diseases: Role of blood-brain barrier

Beta-caryophyllene is an abundant terpene in cannabis, cinnamon, black pepper, cloves, and citrus fruit, delivering a striking, woody-spicy, like cloves and a sweet fruity aroma. Beta-caryophyllene is a Food and Drug Administration-approved food additive with Generally Recognized as Safe status. Interestingly, several biologic activities have been described for beta-caryophyllene, including anti-inflammatory and analgesic effects, neuroprotection against cerebral ischemia and neuronal injury, protection of neurovascular unit against oxidative damage, glial activation and neuroinflammation and anticonvulsant effects. In this chapter, we intend to review the beneficial effects of beta-caryophyllene in the context of psychiatric and neurological diseases. Also, we will analyze the possibility that the blood-brain-barrier may be a central target underlying the beneficial actions of beta-caryophyllene.

IUPHAR review- Preclinical models of neuropathic pain: Evaluating multifunctional properties of natural cannabinoid receptors ligands

Neuropathic pain remains prevalent and challenging to manage and is often comorbid with depression and anxiety. The new approach that simultaneously targets neuropathic pain and the associated comorbidities, such as depression and anxiety, is timely and critical, given the high prevalence and severity of neuropathic pain and the lack of effective analgesics. In this review, we focus on the animal models of neuropathic pain that researchers have used to investigate the analgesic effects of cannabidiol (CBD) and Beta-Caryophyllene (BCP) individually and in combination while addressing the impact of these compounds on the major comorbidity (e.g., depression, anxiety) associated with neuropathic pain. We also addressed the potential targets/mechanisms by which CBD and BCP produce analgesic effects in neuropathic pain models. The preclinical studies examined in this review support CBD and BCP individually and combined as potential alternative analgesics for neuropathic pain while showing beneficial effects on depression and anxiety.

β-Caryophyllene Inhibits Oxaliplatin-Induced Peripheral Neuropathy in Mice: Role of Cannabinoid Type 2 Receptors, Oxidative Stress and Neuroinflammation

Peripheral neuropathy is an important adverse effect caused by some chemotherapeutic agents, including oxaliplatin (OXA). OXA-induced peripheral neuropathy (OIPN) is a challenging condition due to diagnostic complexities and a lack of effective treatment. In this study, we investigated the antiallodynic effect of β-caryophyllene (BCP), a cannabinoid type 2 (CB2) receptor agonist, in a mouse model of OIPN. BCP treatment inhibited OXA-induced mechanical and cold allodynia in both preventive and therapeutic drug treatment regimens. Experiments with the CB2 receptor agonist GW405833 confirmed the role of CB2 receptors in OIPN. The CB2 antagonist SR144528 abrogated the anti-nociceptive effect of BCP on mechanical allodynia, without impacting OXA-induced sensitivity to cold. BCP decreased neuroinflammation, as inferred from TNF, IL-1β, IL-6, and IL-10 profiling, and also reduced ROS production, lipid peroxidation, and 4-hydroxynonenal protein adduct formation in the spinal cords of OXA-treated mice. BCP did not affect the antitumor response to OXA or its impact on blood cell counts, implying that the cytotoxicity of OXA was preserved. These results underscore BCP as a candidate drug for OIPN treatment via CB2 receptor-dependent mechanisms, and anti-inflammatory and antioxidant responses in the spinal cord.

Nutraceuticals for Fibromyalgia and Neuropathic Pain

Both neuropathic pain and fibromyalgia are horrific painful conditions arising due to impairment in the somatosensory nervous system and the musculoskeletal system, respectively. They share some common symptoms like hyperalgesia, allodynia, insomnia, cognitive deficits, and mood disturbances. It is believed that fibromyalgia is the consequence of dysfunction of the central nervous system, autonomic nervous system, imbalance in neurotransmitters, and psychological and emotional stress. Henceforth, these pain syndromes have become a major challenge for healthcare professionals due to their complex etiology and poor availability and effectiveness of the drugs. Notably, the available synthetic drugs possess serious side effects including physical dependence and tolerance. Therefore, researchers are now seeking natural-based therapy for modulating chronic pain conditions. This chapter has been written with the intention of exploring the beneficial effects of various nutraceuticals including herbal dietary supplements in neuropathic pain and fibromyalgia.

Decoding the Postulated Entourage Effect of Medicinal Cannabis: What It Is and What It Isn't

The 'entourage effect' term was originally coined in a pre-clinical study observing endogenous bio-inactive metabolites potentiating the activity of a bioactive endocannabinoid. As a hypothetical afterthought, this was proposed to hold general relevance to the usage of products based on Cannabis sativa L. The term was later juxtaposed to polypharmacy pertaining to full-spectrum medicinal Cannabis products exerting an overall higher effect than the single compounds. Since the emergence of the term, a discussion of its pharmacological foundation and relevance has been ongoing. Advocates suggest that the 'entourage effect' is the reason many patients experience an overall better effect from full-spectrum products. Critics state that the term is unfounded and used primarily for marketing purposes in the Cannabis industry. This scoping review aims to segregate the primary research claiming as well as disputing the existence of the 'entourage effect' from a pharmacological perspective. The literature on this topic is in its infancy. Existing pre-clinical and clinical studies are in general based on simplistic methodologies and show contradictory findings, with the clinical data mostly relying on anecdotal and real-world evidence. We propose that the 'entourage effect' is explained by traditional pharmacological terms pertaining to other plant-based medicinal products and polypharmacy in general (e.g., synergistic interactions and bioenhancement).

Cannabinoid Receptor Type II Ligands from Sandalwood Oil and Synthetic α-Santalol Derivatives

Bioassay-guided fractionation of the essential oil of Santalum album led to the identification of α-santalol (1) and β-santalol (2) as new chemotypes of cannabinoid receptor type II (CB2) ligands with Ki values of 10.49 and 8.19 μM, respectively. Nine structurally new α-santalol derivatives (4a-4h and 5) were synthesized to identify more selective and potent CB2 ligands. Compound 4e with a piperazine structural moiety demonstrated a Ki value of 0.99 μM against CB2 receptor and did not show binding activity against cannabinoid receptor type I (CB1) at 10 μM. Compounds 1, 2, and 4e increased intracellular calcium influx in SH-SY5Y human neuroblastoma cells that were attenuated by CB2 antagonism or inverse agonism, supporting the results that these compounds are CB2 agonists. Molecular docking showed that 1 and 4e had similar binding poses, exhibiting a unique interaction with Thr114 within the CB2 receptor, and that the piperazine structural moiety is required for the binding affinity of 4e. A 200 ns molecular dynamics simulation of CB2 complexed with 4e confirmed the stability of the complex. This structural insight lays a foundation to further design and synthesize more potent and selective α-santalol-based CB2 ligands for drug discovery.

Low Doses of β-Caryophyllene Reduced Clinical and Paraclinical Parameters of an Autoimmune Animal Model of Multiple Sclerosis: Investigating the Role of CB2 Receptors in Inflammation by Lymphocytes and Microglial

Multiple Sclerosis (MS) is a prevalent inflammatory disease in which the immune system plays an essential role in the damage, inflammation, and demyelination of central nervous system neurons (CNS). The cannabinoid receptor type 2 (CB₂) agonists possess anti-inflammatory effects against noxious stimuli and elevate the neuronal survival rate. We attempted to analyze the protective impact of low doses of β-Caryophyllene (BCP) in experimental autoimmune encephalomyelitis (EAE) mice as a chronic MS model. Immunization of female C57BL/6 mice was achieved through two subcutaneous injections into different areas of the hind flank with an emulsion that consisted of myelin Myelin oligodendrocyte glycoprotein (MOG)_35-55 (150 µg) and complete Freund's adjuvant (CFA) (400 µg) with an equal volume. Two intraperitoneal (i.p.) injections of pertussis toxin (300 ng) were performed on the animals on day zero (immunizations day) and 48 h (2nd day) after injection of MOG + CFA. The defensive effect of low doses of BCP (2.5 and 5 mg/kg/d) was investigated in the presence and absence of a CB₂ receptor antagonist (1 mg/kg, AM630) in the EAE model. We also examined the pro/anti-inflammatory cytokine levels and the polarization of brain microglia and spleen lymphocytes in EAE animals. According to our findings, low doses of BCP offered protective impacts in the EAE mice treatment in a CB2 receptor-dependent way. In addition, according to results, BCP decreased the pathological and clinical defects in EAE mice via modulating adaptive (lymphocytes) and innate (microglia) immune systems from inflammatory phenotypes (M₁/Th₁/Th₁₇) to anti-inflammatory (M₂/Th₂/T_reg) phenotypes. Additionally, BCP elevated the anti-inflammatory cytokine IL-10 and reduced blood inflammatory cytokines. BCP almost targeted the systemic immune system more than the CNS immune system. Thus, a low dose of BCP can be suggested as a therapeutic effect on MS treatment with potent anti-inflammatory effects and possibly lower toxicity.

Protective effects of β-caryophyllene on mitochondrial damage and cardiac hypertrophy pathways in isoproterenol-induced myocardial infarcted rats

The cardiac mitochondrial damage and cardiac hypertrophy pathways are intimately associated with the pathology of myocardial infarction (MI). The protective effects of β-caryophyllene on mitochondrial damage and cardiac hypertrophy pathways in isoproterenol-induced myocardial infarcted rats were investigated. Isoproterenol (100 mg/kg body weight) was administered to induce MI. The ST-segment, QT interval, and T wave were widened, and the QRS complex and P wave were shortened in the electrocardiogram (ECG) and the serum cardiac diagnostic markers and heart mitochondrial lipid peroxidation products, calcium ions, and reactive oxygen species (ROS) were elevated and the heart mitochondrial antioxidants, tricarboxylic acid cycle, and respiratory chain enzymes were lessened in isoproterenol-induced myocardial infarcted rats. The heart mitochondrial damage was noted in the transmission electron microscopic study. The whole heart weight was increased and the subunits of nicotinamide adenine dinucleotide phosphate - oxidase 2 (Nox 2) genes such as cybb and p22-phox and cardiac hypertrophy genes such as atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), β -myosin heavy chain (β-MHC), and actin alpha skeletal muscle-1(ACTA-1) were highly expressed in the rat's heart by reverse transcription-polymerase chain reaction study. The β-caryophyllene (20 mg/kg body weight) pre- and co-treatment orally, daily for 21 days reversed changes in ECG and lessened cardiac diagnostic markers, ROS, and whole heart weight and ameliorated mitochondrial damage and Nox/ANP/BNP/β-MHC/ACTA-1cardiac hypertrophy pathways in isoproterenol-induced myocardial infarcted rats. The observed effects might be due to the antioxidant, anti-mitochondrial damaging, and anti-cardiac hypertrophic mechanisms of β-caryophyllene.

Cannabidiol and Beta-Caryophyllene in Combination: A Therapeutic Functional Interaction

Cannabis contains over 500 distinct compounds, which include cannabinoids, terpenoids, and flavonoids. However, very few of these compounds have been studied for their beneficial effects. There is an emerging concept that the constituents of the cannabis plant may work in concert to achieve better therapeutic benefits. This study is aimed at determining if the combination of a minor cannabinoid (cannabidiol, CBD) and a terpene (beta-caryophyllene, BCP) works in concert and if this has any therapeutic value. We used an inflammatory pain model (formalin) in mice to test for any functionality of CBD and BCP in combination. First, we determined the analgesic effect of CBD and BCP individually by establishing dose-response studies. Second, we tested the analgesic effect of fixed-ratio combinations and monitored any adverse effects. Finally, we determined the effect of this combination on inflammation. The combination of CBD and BCP produces a synergistic analgesic effect. This effect was without the cannabinoid receptor-1 side effects. The analgesic effect of CBD and BCP in combination involves an inflammatory mechanism. The combination of these two constituents of the cannabis plant, CBD and BCP, works in concert to produce a therapeutic effect with safety profiles through an inflammatory mechanism.

Emerging roles of keratinocytes in nociceptive transduction and regulation

Keratinocytes are the predominant block-building cells in the epidermis. Emerging evidence has elucidated the roles of keratinocytes in a wide range of pathophysiological processes including cutaneous nociception, pruritus, and inflammation. Intraepidermal free nerve endings are entirely enwrapped within the gutters of keratinocyte cytoplasm and form en passant synaptic-like contacts with keratinocytes. Keratinocytes can detect thermal, mechanical, and chemical stimuli through transient receptor potential ion channels and other sensory receptors. The activated keratinocytes elicit calcium influx and release ATP, which binds to P2 receptors on free nerve endings and excites sensory neurons. This process is modulated by the endogenous opioid system and endothelin. Keratinocytes also express neurotransmitter receptors of adrenaline, acetylcholine, glutamate, and γ-aminobutyric acid, which are involved in regulating the activation and migration, of keratinocytes. Furthermore, keratinocytes serve as both sources and targets of neurotrophic factors, pro-inflammatory cytokines, and neuropeptides. The autocrine and/or paracrine mechanisms of these mediators create a bidirectional feedback loop that amplifies neuroinflammation and contributes to peripheral sensitization.

Anti-Inflammatory and Analgesic Properties of the Cannabis Terpene Myrcene in Rat Adjuvant Monoarthritis

Cannabis-based terpenes are believed to modulate physiological responses to disease and alter the efficacy of cannabinoids in the so-called “entourage effect”. The monoterpene myrcene can reduce nociception produced by noxious thermal and mechanical stimuli as well as reducing acute inflammation. The current study examined the role of myrcene and cannabidiol (CBD) in controlling chronic joint inflammation and pain. Chronic arthritis was induced in male Wistar rats by intra-articular injection of Freund’s complete adjuvant into the right knee. On days 7 and 21 after arthritis induction, joint pain (von Frey hair algesiometry), inflammation (intravital microscopy, laser speckle contrast analysis) and joint histopathology were assessed. Local application of myrcene (1 and 5 mg/kg s.c.) reduced joint pain and inflammation via a cannabinoid receptor mechanism. The combination of myrcene and CBD (200 μg) was not significantly different from myrcene alone. Repeated myrcene treatment had no effect on joint damage or inflammatory cytokine production. These data suggest that topical myrcene has the potential to reduce chronic arthritis pain and inflammation; however, it has no synergistic effect with CBD.

Opioid-sparing effect of cannabinoids for analgesia: an updated systematic review and meta-analysis of preclinical and clinical studies

Cannabinoid co-administration may enable reduced opioid doses for analgesia. This updated systematic review on the opioid-sparing effects of cannabinoids considered preclinical and clinical studies where the outcome was analgesia or opioid dose requirements. We searched Scopus, Cochrane Central Registry of Controlled Trials, Medline, and Embase (2016 onwards). Ninety-two studies met the search criteria including 15 ongoing trials. Meta-analysis of seven preclinical studies found the median effective dose (ED₅₀) of morphine administered with delta-9-tetrahydrocannabinol was 3.5 times lower (95% CI 2.04, 6.03) than the ED₅₀ of morphine alone. Six preclinical studies found no evidence of increased opioid abuse liability with cannabinoid administration. Of five healthy-volunteer experimental pain studies, two found increased pain, two found decreased pain and one found reduced pain bothersomeness with cannabinoid administration; three demonstrated that cannabinoid co-administration may increase opioid abuse liability. Three randomized controlled trials (RCTs) found no evidence of opioid-sparing effects of cannabinoids in acute pain. Meta-analysis of four RCTs in patients with cancer pain found no effect of cannabinoid administration on opioid dose (mean difference -3.8 mg, 95% CI -10.97, 3.37) or percentage change in pain scores (mean difference 1.84, 95% CI -2.05, 5.72); five studies found more adverse events with cannabinoids compared with placebo (risk ratio 1.13, 95% CI 1.03, 1.24). Of five controlled chronic non-cancer pain trials; one low-quality study with no control arm, and one single-dose study reported reduced pain scores with cannabinoids. Three RCTs found no treatment effect of dronabinol. Meta-analyses of observational studies found 39% reported opioid cessation (95% CI 0.15, 0.64, I² 95.5%, eight studies), and 85% reported reduction (95% CI 0.64, 0.99, I² 92.8%, seven studies). In summary, preclinical and observational studies demonstrate the potential opioid-sparing effects of cannabinoids in the context of analgesia, in contrast to higher-quality RCTs that did not provide evidence of opioid-sparing effects.

Evaluation of the terpenes β-caryophyllene, α-terpineol, and γ-terpinene in the mouse chronic constriction injury model of neuropathic pain: possible cannabinoid receptor involvement

Pain is one of the most common reasons to seek medical attention, and chronic pain is a worldwide epidemic. Anecdotal reports suggest cannabis may be an effective analgesic. As cannabis contains the terpenes α-terpineol, β-caryophyllene, and γ-terpinene, we hypothesized these terpenes would produce analgesia in a mouse model of neuropathic pain. We used the chronic constriction injury of the sciatic nerve mouse model, which produces mechanical allodynia, assessed via the von Frey assay, as well as thermal hyperalgesia assessed via the hotplate assay. Compounds were further assessed in tests of locomotor activity, hypothermia, and acute antinociception. Each terpene produced dose-related reversal of mechanical allodynia and thermal hyperalgesia. Thermal hyperalgesia displayed higher sensitivity to the effects of each terpene than mechanical allodynia, and the rank order potency of the terpenes was α-terpineol > β-caryophyllene > γ-terpinene. To examine the involvement of cannabinoid receptors, further tests were conducted in mice lacking either functional cannabinoid type 1 receptors (CB₁R (-/-)) or cannabinoid type 2 receptors (CB₂R (-/-)). Compared to wild type mice, CB₁R (-/-) mice treated with α-terpineol displayed a 2.91-fold decrease in potency to reverse mechanical allodynia; in CB₂R (-/-) mice, the potency of α-terpineol was decreased 11.73-fold. The potency of β-caryophyllene to reverse mechanical allodynia decreased 1.80-fold in CB₂R (-/-) mice. Each terpene produced a subset of effects in tests of locomotor activity, hypothermia, and acute antinociception. These findings suggest α-terpineol, β-caryophyllene, and γ-terpinene may have differential cannabinoid receptor activity and a pharmacological profile that may yield new efficacious analgesics.

Opioidergic Signaling-A Neglected, Yet Potentially Important Player in Atopic Dermatitis

Atopic dermatitis (AD) is one of the most common skin diseases, the prevalence of which is especially high among children. Although our understanding about its pathogenesis has substantially grown in recent years, and hence, several novel therapeutic targets have been successfully exploited in the management of the disease, we still lack curative treatments for it. Thus, there is an unmet societal demand to identify further details of its pathogenesis to thereby pave the way for novel therapeutic approaches with favorable side effect profiles. It is commonly accepted that dysfunction of the complex cutaneous barrier plays a central role in the development of AD; therefore, the signaling pathways involved in the regulation of this quite complex process are likely to be involved in the pathogenesis of the disease and can provide novel, promising, yet unexplored therapeutic targets. Thus, in the current review, we aim to summarize the available potentially AD-relevant data regarding one such signaling pathway, namely cutaneous opioidergic signaling.

A critical review of cannabis in medicine and dentistry: A look back and the path forward

Introduction

In the last two decades, our understanding of the therapeutic utility and medicinal properties of cannabis has greatly changed. This change has been accompanied by widespread cannabis use in various communities and different age groups, especially within the United States. With this increase, we should consider the potential effects of cannabis–hemp on general public health and how they could alter therapeutic outcomes.

Material and Methods

The present investigation examined cannabis use for recreational and therapeutic use and a review of pertinent indexed literature was performed. The focused question evaluates “how cannabis or hemp products impact health parameters and do they provide potential therapeutic value in dentistry, and how do they interact with conventional medicines (drugs).” Indexed databases (PubMed/Medline, EMBASE) were searched without any time restrictions but language was restricted to English.

Results

The review highlights dental concerns of cannabis usage, the need to understand the endocannabinoid system (ECS), cannabinoid receptor system, its endogenous ligands, pharmacology, metabolism, current oral health, and medical dilemma to ascertain the detrimental or beneficial effects of using cannabis–hemp products. The pharmacological effects of pure cannabidiol (CBD) have been studied extensively while cannabis extracts can vary significantly and lack empirical studies. Several metabolic pathways are affected by cannabis use and could pose a potential drug interaction. The chronic use of cannabis is associated with health issues, but the therapeutic potential is multifold since there is a regulatory role of ECS in many pathologies.

Conclusion

Current shortcomings in understanding the benefits of cannabis or hemp products are limited due to pharmacological and clinical effects not being predictable, while marketed products vary greatly in phytocompounds warrant further empirical investigation. Given the healthcare challenges to manage acute and chronic pain, this review highlights both cannabis and CBD‐hemp extracts to help identify the therapeutic application for patient populations suffering from anxiety, inflammation, and dental pain.

Antinociceptive effects of minor cannabinoids, terpenes and flavonoids in Cannabis

Cannabis has been used for centuries for its medicinal properties. Given the dangerous and unpleasant side effects of existing analgesics, the chemical constituents of Cannabis have garnered significant interest for their antinociceptive, anti-inflammatory and neuroprotective effects. To date, Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) remain the two most widely studied constituents of Cannabis in animals. These studies have led to formulations of THC and CBD for human use; however, chronic pain patients also use different strains of Cannabis (sativa, indica and ruderalis) to alleviate their pain. These strains contain major cannabinoids, such as THC and CBD, but they also contain a wide variety of cannabinoid and noncannabinoid constituents. Although the analgesic effects of Cannabis are attributed to major cannabinoids, evidence indicates other constituents such as minor cannabinoids, terpenes and flavonoids also produce antinociception against animal models of acute, inflammatory, neuropathic, muscle and orofacial pain. In some cases, these constituents produce antinociception that is equivalent or greater compared to that produced by traditional analgesics. Thus, a better understanding of the extent to which these constituents produce antinociception alone in animals is necessary. The purposes of this review are to (1) introduce the different minor cannabinoids, terpenes, and flavonoids found in Cannabis and (2) discuss evidence of their antinociceptive properties in animals.

Beta-caryophyllene attenuates short-term recurrent seizure activity and blood-brain-barrier breakdown after pilocarpine-induced status epilepticus in rats

BACKGROUND

Status epilepticus (SE) is a neurological life-threatening condition, resulting from the failure of the mechanisms responsible for seizure termination. SE is often pharmacoresistant and associated with significant morbidity and mortality. Hence, ceasing or attenuating SE and its consequences is of fundamental importance. Beta-caryophyllene is a functional CB2 receptor agonist and exhibit a good safety profile. Besides, it displays beneficial effects in several experimental conditions, including neuroprotective activity. In the present study we aimed to investigate the effects of beta-caryophyllene on pilocarpine-induced SE.

METHODS

Wistar rats were submitted to pilocarpine-induced SE and monitored for 24 hours by video and EEG for short-term recurrence of seizure activity (i.e. seizures occurring within 24 hours after termination of SE). Rats received beta-caryophyllene (100 mg/kg, ip) at 1, 8- and 16-hours after SE. Twenty-four hours after SE we evaluated sensorimotor response, neuronal damage (fluoro jade C staining) and serum albumin infiltration into brain parenchyma.

RESULTS

Beta-caryophyllene-treated animals presented fewer short-term recurrent seizures than vehicle-treated counterparts, suggesting an anticonvulsant effect after SE. Behavioral recovery from SE and the number of fluoro jade C positive cells in the hippocampus and thalamus were not modified by beta-caryophyllene. Treatment with beta-caryophyllene attenuated the SE-induced increase of albumin immunoreactivity in the hippocampus, indicating a protective effect against blood-brain-barrier breakdown.

CONCLUSIONS

Given the inherent difficulties in the treatment of SE and its consequences, present results suggest that beta-caryophyllene deserve further investigation as an adjuvant therapeutic strategy for SE.

Anti-Microbial Activity of Phytocannabinoids and Endocannabinoids in the Light of Their Physiological and Pathophysiological Roles

Antibiotic resistance has become an increasing challenge in the treatment of various infectious diseases, especially those associated with biofilm formation on biotic and abiotic materials. There is an urgent need for new treatment protocols that can also target biofilm-embedded bacteria. Many secondary metabolites of plants possess anti-bacterial activities, and especially the phytocannabinoids of the Cannabis sativa L. varieties have reached a renaissance and attracted much attention for their anti-microbial and anti-biofilm activities at concentrations below the cytotoxic threshold on normal mammalian cells. Accordingly, many synthetic cannabinoids have been designed with the intention to increase the specificity and selectivity of the compounds. The structurally unrelated endocannabinoids have also been found to have anti-microbial and anti-biofilm activities. Recent data suggest for a mutual communication between the endocannabinoid system and the gut microbiota. The present review focuses on the anti-microbial activities of phytocannabinoids and endocannabinoids integrated with some selected issues of their many physiological and pharmacological activities.

The Medicinal Natural Products of Cannabis sativa Linn.: A Review

Cannabis sativa is known among many cultures for its medicinal potential. Its complexity contributes to the historical application of various parts of the plant in ethno-medicines and pharmacotherapy. C. sativa has been used for the treatment of rheumatism, epilepsy, asthma, skin burns, pain, the management of sexually transmitted diseases, difficulties during child labor, postpartum hemorrhage, and gastrointestinal activity. However, the use of C. sativa is still limited, and it is illegal in most countries. Thus, this review aims to highlight the biological potential of the plant parts, as well as the techniques for the extraction, isolation, and characterization of C. sativa compounds. The plant produces a unique class of terpenophenolic compounds, called cannabinoids, as well as non-cannabinoid compounds. The exhaustive profiling of bioactive compounds and the chemical characterization and analysis of C. sativa compounds, which modern research has not yet fully achieved, is needed for the consistency, standardization, and the justified application of Cannabis sativa products for therapeutic purposes. Studies on the clinical relevance and applications of cannabinoids and non-cannabinoid phenols in the prevention and treatment of life-threatening diseases is indeed significant. Furthermore, psychoactive cannabinoids, when chemically standardized and administered under medical supervision, can be the legal answer to the use of C. sativa.

Converting Sugars into Cannabinoids—The State-of-the-Art of Heterologous Production in Microorganisms

The legal cannabis market worldwide is facing new challenges regarding innovation in the production of cannabinoid-based drugs. The usual cannabinoid production involves growing Cannabis sativa L. outdoor or in dedicated indoor growing facilities, followed by isolation and purification steps. This process is limited by the growth cycles of the plant, where the cannabinoid content can deeply vary from each harvest. A game change approach that does not involve growing a single plant has gained the attention of the industry: cannabinoids fermentation. From recombinant yeasts and bacteria, researchers are able to reproduce the biosynthetic pathway to generate cannabinoids, such as (-)-Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD), and (-)-Δ9-tetrahydrocannabivarin (Δ9-THCV). This approach avoids pesticides, and natural resources such as water, land, and energy are reduced. Compared to growing cannabis, fermentation is a much faster process, although its limitation regarding the phytochemical broad range of molecules naturally present in cannabis. So far, there is not a consolidated process for this brand-new approach, being an emerging and promising concept for countries in which cultivation of Cannabis sativa L. is illegal. This survey discusses the techniques and microorganisms already established to accomplish the task and those yet in seeing for the future, exploring upsides and limitations about metabolic pathways, toxicity, and downstream recovery of cannabinoids throughout heterologous production. Therapeutic potential applications of cannabinoids and in silico methodology toward optimization of metabolic pathways are also explored. Moreover, conceptual downstream analysis is proposed to illustrate the recovery and purification of cannabinoids through the fermentation process, and a patent landscape is presented to provide the state-of-the-art of the transfer of knowledge from the scientific sphere to the industrial application.

Antinociceptive and chondroprotective effects of prolonged β-caryophyllene treatment in the animal model of osteoarthritis: Focus on tolerance development

Osteoarthritis (OA) is a chronic joint disease in which cartilage degeneration leads to chronic pain. The endocannabinoid system has attracted attention as an emerging drug target for OA. However, the therapeutic potential of cannabinoids is limited by psychoactive side-effects related to CB1 activation and tolerance development for analgesic effects. β-Caryophyllene (BCP) is a low-efficacy natural agonist of CB2 and a common constituent of human diet with well-established anti-inflammatory properties. The results presented herein show the anti-nociceptive and chondroprotective potential of BCP in an animal model of OA induced by intra-articular injection of monoiodoacetate (MIA). Behavioural assessment included pressure application measurement and kinetic weight bearing tests. Histological assessment of cartilage degeneration was quantified using OARSI scoring. Experiments established the dose-response effects of BCP and pharmacological mechanisms of the antinociceptive action dependent on CB2 and opioid receptors. Chronic BCP treatment was able to hamper cartilage degeneration without producing tolerance for the analgesic effects. The data presented herein show that BCP is able to produce both acute and prolonged antinociceptive and chondroprotective effects. Together with the safety profile and legal status of BCP, these results indicate a novel and promising disease-modifying strategy for treating OA.

Exploring Pharmacological Mechanisms of Essential Oils on the Central Nervous System

Essential oils (EOs) have been traditionally used as ancient remedies to treat many health disorders due to their enormous biological activities. As mainstream allopathic medication currently used for CNS disorders is associated with adverse effects, the search to obtain safer alternatives as compared to the currently marketed therapies is of tremendous significance. Research conducted suggests that concurrent utilization of allopathic medicines and EOs is synergistically beneficial. Due to their inability to show untoward effects, various scientists have tried to elucidate the pharmacological mechanisms by which these oils exert beneficial effects on the CNS. In this regard, our review aims to improve the understanding of EOs' biological activity on the CNS and to highlight the significance of the utilization of EOs in neuronal disorders, thereby improving patient acceptability of EOs as therapeutic agents. Through data compilation from library searches and electronic databases such as PubMed, Google Scholar, etc., recent preclinical and clinical data, routes of administration, and the required or maximal dosage for the observation of beneficial effects are addressed. We have also highlighted the challenges that require attention for further improving patient compliance, research gaps, and the development of EO-based nanomedicine for targeted therapy and pharmacotherapy.

Cannabis and the skin

The public and health care providers are increasingly curious about the potential medical benefits of Cannabis. In vitro and in vivo studies of Cannabis have suggested it has favorable effects on regulating pain, pruritus, and inflammation, making it a potentially attractive therapeutic agent for many dermatologic conditions. The body of literature reporting on the role of cannabinoids in dermatology is in its infancy but growing. We review the current research, possible cutaneous adverse effects, and future directions for cannabinoids and their use in skin cancer, acne, psoriasis, pruritus, dermatitis, scleroderma, dermatomyositis, cutaneous lupus erythematous, epidermolysis bullosa, pain, and wound healing.

Analgesic Potential of Terpenes Derived from Cannabis sativa

Pain prevalence among adults in the United States has increased 25% over the past two decades, resulting in high health-care costs and impacts to patient quality of life. In the last 30 years, our understanding of pain circuits and (intra)cellular mechanisms has grown exponentially, but this understanding has not yet resulted in improved therapies. Options for pain management are limited. Many analgesics have poor efficacy and are accompanied by severe side effects such as addiction, resulting in a devastating opioid abuse and overdose epidemic. These problems have encouraged scientists to identify novel molecular targets and develop alternative pain therapeutics. Increasing preclinical and clinical evidence suggests that cannabis has several beneficial pharmacological activities, including pain relief. Cannabis sativa contains more than 500 chemical compounds, with two principle phytocannabinoids, Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD). Beyond phytocannabinoids, more than 150 terpenes have been identified in different cannabis chemovars. Although the predominant cannabinoids, Δ9-THC and CBD, are thought to be the primary medicinal compounds, terpenes including the monoterpenes β-myrcene, α-pinene, limonene, and linalool, as well as the sesquiterpenes β-caryophyllene and α-humulene may contribute to many pharmacological properties of cannabis, including anti-inflammatory and antinociceptive effects. The aim of this review is to summarize our current knowledge about terpene compounds in cannabis and to analyze the available scientific evidence for a role of cannabis-derived terpenes in modern pain management. SIGNIFICANCE STATEMENT: Decades of research have improved our knowledge of cannabis polypharmacy and contributing phytochemicals, including terpenes. Reform of the legal status for cannabis possession and increased availability (medicinal and recreational) have resulted in cannabis use to combat the increasing prevalence of pain and may help to address the opioid crisis. Better understanding of the pharmacological effects of cannabis and its active components, including terpenes, may assist in identifying new therapeutic approaches and optimizing the use of cannabis and/or terpenes as analgesic agents.

β-caryophyllene, an FDA-Approved Food Additive, Inhibits Methamphetamine-Taking and Methamphetamine-Seeking Behaviors Possibly via CB2 and Non-CB2 Receptor Mechanisms

Recent research indicates that brain cannabinoid CB2 receptors are involved in drug reward and addiction. However, it is unclear whether β-caryophyllene (BCP), a natural product with a CB2 receptor agonist profile, has therapeutic effects on methamphetamine (METH) abuse and dependence. In this study, we used animal models of self-administration, electrical brain-stimulation reward (BSR) and in vivo microdialysis to explore the effects of BCP on METH-taking and METH-seeking behavior. We found that systemic administration of BCP dose-dependently inhibited METH self-administration under both fixed-ratio and progressive-ratio reinforcement schedules in rats, indicating that BCP reduces METH reward, METH intake, and incentive motivation to seek and take METH. The attenuating effects of BCP were partially blocked by AM 630, a selective CB2 receptor antagonist. Genetic deletion of CB2 receptors in CB2-knockout (CB2-KO) mice also blocked low dose BCP-induced reduction in METH self-administration, suggesting possible involvement of a CB2 receptor mechanism. However, at high doses, BCP produced a reduction in METH self-administration in CB2-KO mice in a manner similar as in WT mice, suggesting that non-CB2 receptor mechanisms underlie high dose BCP-produced effects. In addition, BCP dose-dependently attenuated METH-enhanced electrical BSR and inhibited METH-primed and cue-induced reinstatement of drug-seeking in rats. In vivo microdialysis assays indicated that BCP alone did not produce a significant reduction in extracellular dopamine (DA) in the nucleus accumbens (NAc), while BCP pretreatment significantly reduced METH-induced increases in extracellular NAc DA in a dose-dependent manner, suggesting a DA-dependent mechanism involved in BCP action. Together, the present findings suggest that BCP might be a promising therapeutic candidate for the treatment of METH use disorder.

Microscopy-based infrared spectroscopy as a tool to evaluate the influence of essential oil on the surface of loaded bilayered-nanoparticles

Increasing interest in nanoparticles of technological application has been improving their fabrication processes. The encapsulation of essential oils as bioactive compounds has proved to be an excellent alternative to the use of less environment friendly compounds. However, the difficulty of identifying their constitution and interaction with carrier agents have aroused scientific interest and a problem to overcome. Bilayer-based nanoparticles were developed using gelatin and poly-ε-caprolactone (PCL) aiming the encapsulation ofPiper nigrumessential oil. based on atomic force microscopy images and dynamic light scattering analysis, the size of the unloaded and loaded nanoparticles was found around (194 ± 40) and (296 ± 54) nm, respectively. The spatial patterns revealed that the surface of nanoparticles presented different surface roughness, similar shapes and height distribution asymmetry, lower dominant spatial frequencies, and different spatial complexity. Traditional infrared spectroscopy allowed the identification of the nanoparticle outermost layer formed by the gelatin carrier, but microscopy-based infrared spectroscopy revealed a band at 1742 cm^-1related to the carbonyl stretching mode of PCL, as well as a band at 1557 cm^-1due to the amide II group from gelatin. The combination of microscopy and spectroscopy techniques proved to be an efficient alternative to quickly identify differences in chemical composition by evaluating different functional groups in bilayer PLC/gelatin nanoparticles of technological application.

A focused review on CB2 receptor-selective pharmacological properties and therapeutic potential of β-caryophyllene, a dietary cannabinoid

The endocannabinoid system (ECS), a conserved physiological system emerged as a novel pharmacological target for its significant role and potential therapeutic benefits ranging from neurological diseases to cancer. Among both, CB1 and CB2R types, CB2R have received attention for its pharmacological effects as antioxidant, anti-inflammatory, immunomodulatory and antiapoptotic that can be achieved without causing psychotropic adverse effects through CB1R. The ligands activate CB2R are of endogenous, synthetic and plant origin. In recent years, β-caryophyllene (BCP), a natural bicyclic sesquiterpene in cannabis as well as non-cannabis plants, has received attention due to its selective agonist property on CB2R. BCP has been well studied in a variety of pathological conditions mediating CB2R selective agonist property. The focus of the present manuscript is to represent the CB2R selective agonist mediated pharmacological mechanisms and therapeutic potential of BCP. The present narrative review summarizes insights into the CB2R-selective pharmacological properties and therapeutic potential of BCP such as cardioprotective, hepatoprotective, neuroprotective, nephroprotective, gastroprotective, chemopreventive, antioxidant, anti-inflammatory, and immunomodulator. The available evidences suggest that BCP, can be an important candidate of plant origin endowed with CB2R selective properties that may provide a pharmacological rationale for its pharmacotherapeutic application and pharmaceutical development like a drug. Additionally, given the wide availability in edible plants and dietary use, with safety, and no toxicity, BCP can be promoted as a nutraceutical and functional food for general health and well-being. Further, studies are needed to explore pharmacological and pharmaceutical opportunities for therapeutic and preventive applications of use of BCP in human diseases.

Chemical composition, antioxidant activities and antibacterial activities of essential oil from Erythrina caffra Thunb. growing in South Africa

INTRODUCTION

Essential oils from plants are recognized as one of the most promising secondary metabolites for the development of cheap and safer drugs. While Erythrina caffra has been prominently used in folk medicine for the treatment of microbial infections, there is dearth of information on the pharmacological effectiveness and chemical composition of its essential oil. The study, therefore, aimed at identifying the chemical composition and biological activities of the essential oil of Erythrina caffra.

METHODS

In this study, the essential oil was extracted with all-glass Clevenger. The antioxidant activities of the essential oil and antibacterial susceptibility assay by agar well diffusion techniques were assessed while GC-MS analysis was performed to identify the chemical constituents of the essential oil.

RESULTS

The study showed that the radical scavenging activity of the essential oil increases as the concentration of the essential oil increases. All bacterial isolates were susceptible to essential oil with the exception of Salmonella typhimurium and Pseudomonas aeruginosa producing inhibition zones ranging between 22 ± 1.3 and 35 ± 2.1 mm in the susceptible isolates. The GC-MS chromatogram indicated there are 35 bioactive compounds in the essential oil and Caryophyllene oxide (53.54%), [1S-(1α,7α,8aβ)]-1,2,3,5,6,7,8,8a-octa-1 - hydro-1,8a-dimethyl-7-(1-methylethenyl)-Naphthalene (7.81%), Kauran-18-al (6.49%), 10,10-Dimethyl-2,6-dimethylenebicy clo[7.2.0]undecan-5.beta.-ol (5.83%), 10s,11s-Himachala-3(12),4-diene (4.51%), Caryophyllene (3.65%) and 1- Hexanol (3.31%) were the most prominent compounds.

CONCLUSION

Excessive production of free radicals or reactive oxygen species (ROS) causes oxidative stress and disease. Oxidative stress resulting from imbalance between excessive generation of free radicals and inadequate antioxidant defense system has been linked to pathogenesis of many diseases. The essential oil of E. caffra stem bark extract possess antimicrobial and good antioxidant activities and its rich level of phytochemicals can be used as either dietary or complementary agents.

Development and Translation of NanoBEO, a Nanotechnology-Based Delivery System of Bergamot Essential Oil Deprived of Furocumarins, in the Control of Agitation in Severe Dementia

Dementia is one of the most common causes of disability worldwide characterized by memory loss, cognitive impairment, and behavioral and psychological symptoms (BPSD), including agitation. Treatment of the latter consists of the off-label use of harmful atypical antipsychotics, though a significant reduction is afforded by pain control. The use of an essential oil endowed with analgesic properties and devoid of toxicity would represent an important option for the management of agitation in dementia. Therefore, the aim of this study was to engineer a nanotechnology delivery system based on solid lipid nanoparticles loaded with bergamot essential oil (BEO) and devised in the pharmaceutical form of an odorless cream (NanoBEO) to confirm its analgesic efficacy for further development and application to control agitation in dementia. BEO has proven strong antinociceptive and anti-allodynic properties and, in its bergapten-free form, it is completely devoid of phototoxicity. NanoBEO has been studied in vivo confirming the previously reported analgesic activity of BEO to which is now added its anti-itching properties. Due to the nanotechnology delivery system, the stability of titrated BEO components is guaranteed. Finally, the latter invention, currently under patent consideration, is smell-devoid allowing efficacy and safety to be established in double-blind clinical trials; until now the latter studies have been impeded in aromatherapy by the strong odor of essential oils. A clinical trial NCT04321889 has been designed to provide information about the efficacy and safety of NanoBEO on agitation and pain in patients suffering from severe dementia.

Beta-caryophyllene inhibits cocaine addiction-related behavior by activation of PPARα and PPARγ: repurposing a FDA-approved food additive for cocaine use disorder

Cocaine abuse continues to be a serious health problem worldwide. Despite intense research, there is still no FDA-approved medication to treat cocaine use disorder (CUD). In this report, we explored the potential utility of beta-caryophyllene (BCP), an FDA-approved food additive for the treatment of CUD. We found that BCP, when administered intraperitoneally or intragastrically, dose-dependently attenuated cocaine self-administration, cocaine-conditioned place preference, and cocaine-primed reinstatement of drug seeking in rats. In contrast, BCP failed to alter food self-administration or cocaine-induced hyperactivity. It also failed to maintain self-administration in a drug substitution test, suggesting that BCP has no abuse potential. BCP was previously reported to be a selective CB2 receptor agonist. Unexpectedly, pharmacological blockade or genetic deletion of CB1, CB2, or GPR55 receptors in gene-knockout mice failed to alter BCP's action against cocaine self-administration, suggesting the involvement of non-CB1, non-CB2, and non-GPR55 receptor mechanisms. Furthermore, pharmacological blockade of μ opioid receptor or Toll-like receptors complex failed to alter, while blockade of peroxisome proliferator-activated receptors (PPARα, PPARγ) reversed BCP-induced reduction in cocaine self-administration, suggesting the involvement of PPARα and PPARγ in BCP's action. Finally, we used electrical and optogenetic intracranial self-stimulation (eICSS, oICSS) paradigms to study the underlying neural substrate mechanisms. We found that BCP is more effective in attenuation of cocaine-enhanced oICSS than eICSS, the former driven by optical activation of midbrain dopamine neurons in DAT-cre mice. These findings indicate that BCP may be useful for the treatment of CUD, likely by stimulation of PPARα and PPARγ in the mesolimbic system.

Peripheral Mechanisms of Neuropathic Pain-the Role of Neuronal and Non-Neuronal Interactions and Their Implications for Topical Treatment of Neuropathic Pain

Neuropathic pain in humans arises as a consequence of injury or disease of somatosensory nervous system at peripheral or central level. Peripheral neuropathic pain is more common than central neuropathic pain, and is supposed to result from peripheral mechanisms, following nerve injury. The animal models of neuropathic pain show extensive functional and structural changes occurring in neuronal and non-neuronal cells in response to peripheral nerve injury. These pathological changes following damage lead to peripheral sensitization development, and subsequently to central sensitization initiation with spinal and supraspinal mechanism involved. The aim of this narrative review paper is to discuss the mechanisms engaged in peripheral neuropathic pain generation and maintenance, with special focus on the role of glial, immune, and epithelial cells in peripheral nociception. Based on the preclinical and clinical studies, interactions between neuronal and non-neuronal cells have been described, pointing out at the molecular/cellular underlying mechanisms of neuropathic pain, which might be potentially targeted by topical treatments in clinical practice. The modulation of the complex neuro-immuno-cutaneous interactions in the periphery represents a strategy for the development of new topical analgesics and their utilization in clinical settings.

Therapeutic Potential of Cannabidiol (CBD) for Skin Health and Disorders

Though there is limited research confirming the purported topical benefits of cannabinoids, it is certain that cutaneous biology is modulated by the human endocannabinoid system (ECS). Receptors from the ECS have been identified in the skin and systemic abuse of synthetic cannabinoids, and their analogs, have also been associated with the manifestation of dermatological disorders, indicating the effects of the ECS on cutaneous biology. In particular, cannabidiol (CBD), a non-psychoactive compound from the cannabis plant, has garnered significant attention in recent years for its anecdotal therapeutic potential for various pathologies, including skin and cosmetic disorders. Though a body of preclinical evidence suggests topical application of CBD may be efficacious for some skin disorders, such as eczema, psoriasis, pruritis, and inflammatory conditions, confirmed clinical efficacy and elucidation of underlying molecular mechanisms have yet to be fully identified. This article provides an update on the advances in CBD research to date and the potential areas of future exploration.

Protective Effects of (E)-β-Caryophyllene (BCP) in Chronic Inflammation

(E)-β-caryophyllene (BCP) is a bicyclic sesquiterpene widely distributed in the plant kingdom, where it contributes a unique aroma to essential oils and has a pivotal role in the survival and evolution of higher plants. Recent studies provided evidence for protective roles of BCP in animal cells, highlighting its possible use as a novel therapeutic tool. Experimental results show the ability of BCP to reduce pro-inflammatory mediators such as tumor necrosis factor-alfa (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), thus ameliorating chronic pathologies characterized by inflammation and oxidative stress, in particular metabolic and neurological diseases. Through the binding to CB2 cannabinoid receptors and the interaction with members of the family of peroxisome proliferator-activated receptors (PPARs), BCP shows beneficial effects on obesity, non-alcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH) liver diseases, diabetes, cardiovascular diseases, pain and other nervous system disorders. This review describes the current knowledge on the biosynthesis and natural sources of BCP, and reviews its role and mechanisms of action in different inflammation-related metabolic and neurologic disorders.

Citrus hystrix Extracts Protect Human Neuronal Cells against High Glucose-Induced Senescence

Citrus hystrix (CH) is a beneficial plant utilized in traditional folk medicine to relieve various health ailments. The antisenescent mechanisms of CH extracts were investigated using human neuroblastoma cells (SH-SY5Y). Phytochemical contents and antioxidant activities of CH extracts were analyzed using a gas chromatograph–mass spectrometer (GC-MS), 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assay and 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) assay. Effects of CH extracts on high glucose-induced cytotoxicity, reactive oxygen species (ROS) generation, cell cycle arrest and cell cycle-associated proteins were assessed using a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tetrazolium (MTT) assay, non-fluorescent 2′, 7′-dichloro-dihydrofluorescein diacetate (H₂DCFDA) assay, flow cytometer and Western blot. The extracts protected neuronal senescence by inhibiting ROS generation. CH extracts induced cell cycle progression by releasing senescent cells from the G1 phase arrest. As the Western blot confirmed, the mechanism involved in cell cycle progression was associated with the downregulation of cyclin D1, phospho-cell division cycle 2 (pcdc2) and phospho-Retinoblastoma (pRb) proteins. Furthermore, the Western blot showed that extracts increased Surtuin 1 (SIRT1) expression by increasing the phosphorylation of Glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Collectively, CH extracts could protect high glucose-induced human neuronal senescence by inducing cell cycle progression and up-regulation of SIRT1, thus leading to the improvement of the neuronal cell functions.

Preparation and Characterization of Liposomal β-Caryophyllene (Rephyll) by Nanofiber Weaving Technology and Its Effects on Delayed Onset Muscle Soreness (DOMS) in Humans: A Randomized, Double-Blinded, Crossover-Designed, and Placebo-Controlled Study

Delayed onset muscle soreness (DOMS) is a complex spreading out, which is related to swelling of muscles, tenderness, rigidity, pain, disruption of muscle fiber, alteration in the kinematics of joint, acute tissue damage, and reduction in power and strength. β-Caryophyllene (BCP), a potent phytocannabinoid, could play an important role in managing DOMS because of its wide diversity of biological activities, particularly its anti-inflammatory activity; however, its poor stability in light, temperature, high volatility, and insolubility can restrict the medical practices. In this study, liposomal β-caryophyllene (Rephyll) was designed and established in powder form constructed by the nanofiber weaving technology to improve the bioavailability of BCP with improved stability. Rephyll was characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, and differential scanning calorimetry studies. Encapsulation efficiency, loading capacity, and in vitro release studies revealed that Rephyll can be an auspicious drug delivery arrangement for BCP. The effects of Rephyll were evaluated by a randomized, double-blinded, crossover-designed, placebo-controlled study. The oral consumption of Rephyll significantly reduced the pain visual assessment score, revealing that Rephyll effectively reduced DOMS with improved recovery without any side effects due to the bioavailable form of the phytocannabinoid BCP in the liposomal powder formulation.

Plant Natural Sources of the Endocannabinoid (E)-β-Caryophyllene: A Systematic Quantitative Analysis of Published Literature

(E)-β-caryophyllene (BCP) is a natural sesquiterpene hydrocarbon present in hundreds of plant species. BCP possesses several important pharmacological activities, ranging from pain treatment to neurological and metabolic disorders. These are mainly due to its ability to interact with the cannabinoid receptor 2 (CB2) and the complete lack of interaction with the brain CB1. A systematic analysis of plant species with essential oils containing a BCP percentage > 10% provided almost 300 entries with species belonging to 51 families. The essential oils were found to be extracted from 13 plant parts and samples originated from 56 countries worldwide. Statistical analyses included the evaluation of variability in BCP% and yield% as well as the statistical linkage between families, plant parts and countries of origin by cluster analysis. Identified species were also grouped according to their presence in the Belfrit list. The survey evidences the importance of essential oil yield evaluation in support of the chemical analysis. The results provide a comprehensive picture of the species with the highest BCP and yield percentages.

Electroacupuncture Pretreatment Attenuates Intestinal Injury after Autogenous Orthotopic Liver Transplantation in Rats via the JAK/STAT Pathway

Background

Liver transplantation induces self-injury and affects remote organs, such as the lung, kidney, and intestine. Postoperative intestinal dysfunction has been associated with prolonged hospitalization and affects a patient's health and quality of life. Electroacupuncture (EA) has been proven effective in multiple organ protection. However, the potential mechanism underlying the protective effects of EA on intestinal injury after liver transplantation remains unclear.

Methods

After establishing an autogenous orthotopic liver transplantation (AOLT) model, we studied the effects of EA pretreatment on intestinal injury after AOLT. We used the JAK2-specific inhibitor AG490 to explore the underlying mechanism. Histological analysis and apoptosis assays were used to evaluate intestinal injury. Oxidative stress index and inflammatory response were also measured after AOLT. Furthermore, we detected the phosphorylation levels of JAK2, STAT1, and STAT3 by Western blot.

Results

We found that pretreatment with EA alleviated intestinal injury after AOLT, as shown by HE staining and TUNEL methods. EA pretreatment inhibited the expressions of p-JAK2, p-STAT1, and p-STAT3 in the intestines after AOLT. Upon treatment with JAK2-specific inhibitor AG490, intestinal injury was balanced.

Conclusion

The data indicated EA pretreatment alleviated intestinal injury after AOLT by inhibiting the JAK/STAT signaling pathway. These results provide basic evidence to support the potential therapeutic efficacy of EA.

A Systematic Review of Essential Oils and the Endocannabinoid System: A Connection Worthy of Further Exploration

Aromatic compounds have a long history of use as medicines in most recorded cultures. An increasing interest in these therapeutic volatile molecules in both scientific and lay communities has led to the advancement of essential oils as phytomedicines. Recent discoveries suggest essential oils augment the endocannabinoid system in a positive manner to mitigate various pathologies. However, the exact mechanisms whereby essential oils influence endocannabinoid system activity are not fully known, these studies provide a glimpse into their involvement and warrant further evaluation. Additional study of the interaction between essential oils and the endocannabinoid system may lead to promising phytomedicines for the treatment of diseases and conditions involving dysregulation or activation of the endocannabinoid system.

Transient expression and purification of β-caryophyllene synthase in Nicotiana benthamiana to produce β-caryophyllene in vitro

The sesquiterpene β-caryophyllene is an ubiquitous component in many plants that has commercially been used as an aroma in cosmetics and perfumes. Recent studies have shown its potential use as a therapeutic agent and biofuel. Currently, β-caryophyllene is isolated from large amounts of plant material. Molecular farming based on the Nicotiana benthamiana transient expression system may be used for a more sustainable production of β-caryophyllene. In this study, a full-length cDNA of a new duplicated β-caryophyllene synthase from Artemisia annua (AaCPS1) was isolated and functionally characterized. In order to produce β-caryophyllene in vitro, the AaCPS1 was cloned into a plant viral-based vector pEAQ-HT. Subsequently, the plasmid was transferred into the Agrobacterium and agroinfiltrated into N. benthamiana leaves. The AaCPS1 expression was analyzed by quantitative PCR at different time points after agroinfiltration. The highest level of transcripts was observed at 9 days post infiltration (dpi). The AaCPS1 protein was extracted from the leaves at 9 dpi and purified by cobalt–nitrilotriacetate (Co-NTA) affinity chromatography using histidine tag with a yield of 89 mg kg⁻¹ fresh weight of leaves. The protein expression of AaCPS1 was also confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blot analyses. AaCPS1 protein uses farnesyl diphosphate (FPP) as a substrate to produce β-caryophyllene. Product identification and determination of the activity of purified AaCPS1 were done by gas chromatography–mass spectrometry (GC–MS). GC–MS results revealed that the AaCPS1 produced maximum 26.5 ± 1 mg of β-caryophyllene per kilogram fresh weight of leaves after assaying with FPP for 6 h. Using AaCPS1 as a proof of concept, we demonstrate that N. benthamiana can be considered as an expression system for production of plant proteins that catalyze the formation of valuable chemicals for industrial applications.

Pharmacological and molecular docking assessment of cryptotanshinone as natural-derived analgesic compound

Medicinal plants from traditional chinese medicine are used increasingly worldwide for their benefits to health and quality of life for the relevant clinical symptoms related to pain. Among them, Salvia miltiorrhiza Bunge is traditionally used in asian countries as antioxidant, anticancer, anti-inflammatory and analgesic agent. In this context, several evidences support the hypothesis that some tanshinones, in particular cryptotanshinone (CRY), extracted from the roots (Danshen) of this plant exhibit analgesic actions. However, it is surprisingly noted that no pharmacological studies have been carried out to explore the possible analgesic action of this compound in terms of modulation of peripheral and/or central pain. Therefore, in the present study, by using peripheral and central pain models of nociception, such as tail flick and hot plate test, the analgesic effect of CRY in mice was evaluated. Successively, by the aim of a computational approach, we have evaluated the interaction mode of this diterpenoid on opioid and cannabinoid system. Finally, CRY was dosed in mice serum by an HPLC method validated according to European Medicines Agency guidelines validation rules. Here, we report that CRY displayed anti-nociceptive activity on both hot plate and tail flick test, with a prominent long-lasting peripheral analgesic effect. These evidences were indirectly confirmed after the daily administration of the tanshinone for 7 and 14 days. In addition, the analgesic effect of CRY was reverted by naloxone and cannabinoid antagonists and amplified by arginine administration. These findings were finally supported by HPLC and docking studies, that revealed a noteworthy presence of CRY on mice serum 1 h after its intraperitoneal administration and a possible interaction of tested compound on μ and k receptors. Taken together, these results provide a new line of evidences showing that CRY can produce analgesia against various phenotypes of nociception with a mechanism that seems to be related to an agonistic activity on opioid system.

Antinociceptive Effect of the Essential Oil of Schinus terebinthifolius (female) Leaves on Adult Zebrafish (Danio rerio)

Schinus terebinthifolius Raddi (Anacardiaceae) is popularly known in Brazil as aroeira-da-praia and has pharmacological use as an astringent, antidiarrheal, anti-inflammatory, depurative, diuretic, and antifebrile agent. Although the neuropathic antinociceptive potential of S. terebinthifolius fruits has already been investigated, this study is the first one to analyze the acute antinociceptive effect of the essential oil of S. terebinthifolius (female) leaves (EOFSt) on adult zebrafish. EOFSt was submitted to antioxidant activity evaluation by two methods (ferrous ion-chelating capacity [FIC] and β-carotene). The animals (n = 6/group) were treated orally (20 μL) with EOFSt (0.1, 0.5, or 1.0 mg/mL) or vehicle (0.9% sodium chloride [NaCl]; 20 μL), and submitted to nociception (formalin, cinnamaldehyde, capsaicin, glutamate, acidic saline, and hypertonic saline). Possible neuromodulation mechanisms, as well motor alterations and toxicity were also evaluated. In the FIC assay, EOFSt showed ferrous ion-chelating capacity in ∼40% to 90%. Regarding the β-carotene bleaching assay, EOFSt showed inhibition in a 58% to 80% range. Oral administration of EOFSt showed no acute toxicity and did not alter the locomotor system of aZF, and reduced the nociceptive behavior in all tested models. These effects of EOFSt were significantly similar to those of morphine, used as a positive control. The antinociceptive effect of EOFSt was inhibited by naloxone, L-NAME, ketamine, camphor, ruthenium red, and amiloride. The antinociceptive effect of the EOFSt cornea was inhibited by capsazepine. EOFSt has the pharmacological potential for acute pain treatment and this effect is modulated by the opioid system, NMDA receptors, and transient receptor potential ankyrin 1 (TRPA1), transient receptor potential vanilloid 1 (TRPV1), and acid-sensing ion channels. The EOFSt also has the pharmacological potential for corneal pain treatment and this effect is modulated by the TRPV1 channel.

β-Caryophyllene, a dietary terpenoid, inhibits nicotine taking and nicotine seeking in rodents

BACKGROUND AND PURPOSE

β-Caryophyllene (BCP) is a plant-derived terpenoid used as a food additive for many decades. Recent studies indicate that BCP is a cannabinoid CB₂ receptor agonist with medical benefits for a number of human diseases. However, little is known about its therapeutic potential for drug abuse and addiction.

EXPERIMENT APPROACH

We used pharmacological, transgenic, and optogenetic approaches to systematically evaluate the effects of BCP on nicotine-taking and nicotine-seeking behaviour in animal models of drug self-administration, electrical, and optical brain-stimulation reward.

KEY RESULTS

Systemic administration of BCP dose-dependently inhibited nicotine self-administration and motivation for nicotine seeking in rats and mice. The reduction in nicotine self-administration was blocked by AM630, a selective CB₂ receptor antagonist, but not by AM251, a selective CB₁ receptor antagonist, suggesting involvement of a CB₂ receptor mechanism. Genetic deletion of CB₂ receptors in mice blocked the reduction in nicotine self-administration produced only by low doses, but not by high doses, of BCP, suggesting involvement of both CB₂ and non-CB₂ receptor mechanisms. Furthermore, in the intracranial self-stimulation paradigm, BCP attenuated electrical brain-stimulation reward and nicotine-enhanced brain-stimulation reward in rats. Lastly, BCP also attenuated brain-stimulation reward maintained by optogenetic stimulation of dopaminergic neurons in the ventral tegmental area in DAT-cre mice, suggesting the involvement of a dopamine-dependent mechanism in BCP's action.

CONCLUSIONS AND IMPLICATIONS

The present findings suggest that BCP has significant anti-nicotine effects via both CB₂ and non-CB₂ receptor mechanisms and, therefore, deserves further study as a potential new pharmacotherapy for cigarette smoking cessation.