Cannabinoid Delivery Systems for Pain and Inflammation Treatment

Medical Marijuana for Pain Management in Hospice Care as a Complementary Approach to Scheduled Opioids: A Single Arm Study

Background: Opioid therapy is critical for pain relief for most hospice patients but may be limited by adverse side effects. Combining medical cannabis with opioids may help mitigate adverse effects while maintaining effective pain relief. Aim: This single-arm study investigated the impact of combined medical cannabis/opioid therapy on pain relief, opioid dose, appetite, respiratory function, well-being, nausea, and adverse events in hospice inpatients. Design: Adult hospice inpatients using scheduled oral, parenteral, or transdermal opioids for pain were administered standardized oral medical cannabis, 40 mg CBD/1.5 mg THC or 80 mg CBD/3 mg THC. Descriptive statistics detailed demographic and clinical baseline characteristics, the Mann-Whitney test compared outcomes, and the longitudinal mixed effects regression model analyzed longitudinal effects of combined therapy. Setting/Participants: Sixty-six inpatients at The Connecticut Hospital, Inc. were assessed over 996 treatment days; average age was 68.2 ± 12.9 years, 90.9% were white. Cancer was the most common diagnosis. Results: The medical cannabis/opioid combination showed a significant longitudinal reduction in pain intensity (P = .0029) and a non-significant trend toward lower opioid doses. Well-being, appetite, nausea, and respiratory function showed non-statistically significant changes. Three patients (4.5%) experienced minor, reversible adverse events potentially related to medical cannabis. No serious or life-threatening adverse events were seen. Conclusion: Combination medical cannabis/opioid therapy showed statistically significant pain relief and may have the potential for reducing opioid dose and mitigating opioid toxicity, offering a safe pain management alternative to opioids alone for patients in end-of-life care settings, and warrants further investigation in larger controlled trials.

Cannabinoids in the Inflamed Synovium Can Be a Target for the Treatment of Rheumatic Diseases

The management of rheumatic diseases has noticeably changed in recent years with the development of targeted therapeutic agents, namely, biological disease-modifying antirheumatic drugs. Identifying essential signaling pathways and factors crucial for the development and progression of these diseases remains a significant challenge. Therapy could be used to delay the onset or reduce harm. The endocannabinoid system's presence within the synovium can be identified as a suggested target for therapeutic interventions due to its role in modulating pain, inflammation, and joint metabolism. This review brings together the most pertinent information concerning the actions of the endocannabinoid system present in inflamed synovial tissue and its interaction with phytocannabinoids and synthetic cannabinoids, which can be used from a therapeutic perspective to minimize the inflammatory and pain processes typical of osteoarthritis and rheumatoid arthritis.

Cannabidiol plus krill oil supplementation improves chronic stifle osteoarthritis in dogs: A double-blind randomized controlled trial

Osteoarthritis (OA) is the most common orthopedic disorder characterized by chronic inflammation and pain in dogs and cats. Cannabis spp. contains cannabidiol (CBD), a substance with pain relief and anti-inflammatory properties in different animals including dogs with OA. The use of CBD supplements has been increasingly intertwining in veterinary medicine. This study aimed to evaluate the clinical efficacy of CBD + krill oil-supplemented biscuit against canine OA. In total, 30 dogs with stifle OA were randomized and divided into the placebo, krill oil, and CBD + krill oil groups. The Canine Brief Pain Inventory questionnaire was used to evaluate the efficacy of each treatment against pain. Stifle temperature was monitored to identify degrees of stifle inflammation. Two and one dogs in the placebo group were excluded from the study due to worsening lameness and increased pain interference score (PIS) and pain severity score (PSS) at days 14 and 28, respectively. The PIS and PSS scores of the krill oil and CBD + krill oil groups gradually and significantly improved after two weeks of treatment. The CBD + krill oil group had better PIS and PSS scores than the placebo and krill oil groups. However, there was no statistically significant difference in the PIS and PSS scores between the krill oil and CBD + krill oil groups. The stifle temperature of the three groups at different periods did not significantly differ. In conclusion, CBD + krill oil supplements are safe against canine OA. CBD can reduce pain and inflammation.

Cannabidiol reverts the malignant phenotype of hepatocellular carcinoma cells via the GPR55/TP53/MAPK axis

Cannabidiol (CBD) has antioxidant and anti-inflammatory activities. However, the anti-tumor effect of CBD on hepatocellular carcinoma (HCC) remains unclear. Here, we investigated whether CBD displays anti-tumorigenic effects in HCC cells and whether it could reduce tumorigenesis and metastases in vivo. First, this study treated HCC cells with different concentrations of CBD, followed by analyzing the changes in the proliferative, apoptotic, migratory and invasive abilities. The effects of CBD on the growth and metastasis of HCC cells in vivo were verified by tumorigenesis and metastasis assays. Subsequently, the target genes of CBD were predicted through the SwissTarget website and the genes differentially expressed in cells after CBD treatment were analyzed by microarray for intersection. The enrichment of the pathways after CBD treatment was analyzed by KEGG enrichment analysis, followed by western blot validation. Finally, rescue assays were used to validate the functions of genes as well as pathways in the growth and metastasis of HCC cells. A significant weakening of the ability of HCC cells to grow and metastasize in vitro and in vivo was observed upon CBD treatment. Mechanistically, CBD reduced GRP55 expression in HCC cells, along with increased TP53 expression and blocked MAPK signaling activation. In CBD-treated cells, the anti-tumor of HCC cells was restored after overexpression of GRP55 or deletion of TP53. CBD inhibits the MAPK signaling activation and increases the TP53 expression by downregulating GRP55 in HCC cells, thereby suppressing the growth and metastasis of HCC cells.

Cannabinoids' Role in Modulating Central and Peripheral Immunity in Neurodegenerative Diseases

Cannabinoids (the endocannabinoids, the synthetic cannabinoids, and the phytocannabinoids) are well known for their various pharmacological properties, including neuroprotective and anti-inflammatory features, which are fundamentally important for the treatment of neurodegenerative diseases. The aging of the global population is causing an increase in these diseases that require the development of effective drugs to be even more urgent. Taking into account the unavailability of effective drugs for neurodegenerative diseases, it seems appropriate to consider the role of cannabinoids in the treatment of these diseases. To our knowledge, few reviews are devoted to cannabinoids' impact on modulating central and peripheral immunity in neurodegenerative diseases. The objective of this review is to provide the best possible information about the cannabinoid receptors and immuno-modulation features, peripheral immune modulation by cannabinoids, cannabinoid-based therapies for the treatment of neurological disorders, and the future development prospects of making cannabinoids versatile tools in the pursuit of effective drugs.

Cannabinoid levels description in a cohort of patients with chronic and neuropathic pain treated with Cannabis decoction: A possible role of TDM

The phytocomplex of Cannabis is made up of approximately 500 substances: terpeno-phenols metabolites, including Δ-9-tetrahydrocannabinol and cannabidiol, exhibit pharmacological activity. Medical Cannabis has several pharmacological potential applications, in particular in the management of chronic and neuropathic pain. In the literature, a few data are available concerning cannabis pharmacokinetics, efficacy and safety. Thus, aim of the present study was the evaluation of cannabinoid pharmacokinetics in a cohort of patients, with chronic and neuropathic pain, treated with inhaled medical cannabis and decoction, as a galenic preparation. In this study, 67 patients were enrolled. Dried flower tops with different THC and CBD concentrations were used: Bedrocan® medical cannabis with THC level standardized at 19% and with a CBD level below 1%, Bediol® medical cannabis with THC and CBD level standardized at similar concentration of 6.5% and 8%, respectively. Cannabis was administered as a decoction in 47 patients and inhaled in 11 patients. The blood withdrawn was obtained before the new dose administration at the steady state and metabolites plasma concentrations were measured with an UHPLC-MS/MS method. Statistically significant differences were found in cannabinoids plasma exposure between inhaled and oral administration of medical cannabis, between male and female and cigarette smokers. For the first time, differences in cannabinoid metabolites exposures between different galenic formulations were suggested in patients. Therapeutic drug monitoring could be useful to allow for dose adjustment, but further studies in larger cohorts of patients are required in order to confirm these data.

Immunomodulatory effects of cannabinoids against viral infections: a review of its potential use in SARS-CoV2 infection

The COVID-19 pandemic is a global health crisis affecting millions of people worldwide. Along with vaccine development, there is also a priority to discover new drugs and treatments. One approach involves modulating the immune system to manage inflammation and cytokine storms. Patients with a high severity of complications exhibit a high level of inflammatory cytokines, particularly IL-6, in the airways and other infected tissues. Several studies have reported the function of the endocannabinoid system in regulating inflammation and different immune responses. Cannabinoids are a class of natural chemicals found in the Cannabis plant. Recently, the anti-inflammatory properties of cannabinoids and their mediatory immunosuppression mechanisms through the endocannabinoid system have engrossed scientists in the health field for infectious conditions. Research suggests that the immune system can regulate cytokine activation through cannabinoid receptors, particularly with Cannabidiol (CBD), the second most prevalent compound in cannabis. While CBD has been deemed safe by the World Health Organization and shows no signs of abuse potential, excessive CBD use may lead to respiratory depression. CBD shows promise in reducing immune cell recruitment and cytokine storms in organs affected by SARS-CoV2. However, before clinical use, it's crucial to evaluate cannabinoid-based medications' active ingredient concentrations and potential interactions with other drugs, along with associated side effects. Indication-based dosing, consistent formulations, and ensuring purity and potency are essential. This review highlights cannabinoids' effects on COVID-19 management and prognosis, drawing from preclinical and clinical studies.

Development, Characterization and In Vitro Gastrointestinal Release of PLGA Nanoparticles Loaded with Full-Spectrum Cannabis Extracts

Cannabinoids, such as ∆9-tetrahydrocannabinol (THC) and cannabidiol (CBD), are effective bioactive compounds that improve the quality of life of patients with certain chronic conditions. The copolymer poly(lactic-co-glycolic acid) (PLGA) has been used to encapsulate such compounds separately, providing pharmaceutical grade edible products with unique features. In this work, a variety of PLGA based nanoformulations that maintain the natural cannabinoid profile found in the plant (known as full-spectrum) are proposed and evaluated. Three different cannabis sources were used, representing the three most relevant cannabis chemotypes. PLGA nanocapsules loaded with different amounts of cannabinoids were prepared by nanoemulsion, and were then functionalized with three of the most common coating polymers: pectin, alginate and chitosan. In order to evaluate the suitability of the proposed formulations, all the synthesized nanocapsules were characterized, and their cannabinoid content, size, zeta-potential, morphology and in vitro bioaccessibility was determined. Regardless of the employed cannabis source, its load and the functionalization, high cannabinoid content PLGA nanocapsules with suitable particle size and zeta-potential were obtained. Study of nanocapsules' morphology and in vitro release assays in gastro-intestinal media suggested that high cannabis source load may compromise the structure of nanocapsules and their release properties, and hence, the use of lower content of cannabis source is recommended.

An open-label feasibility trial of transdermal cannabidiol for hand osteoarthritis

Hand osteoarthritis (OA) is an irreversible degenerative condition causing chronic pain and impaired functionality. Existing treatment options are often inadequate. Cannabidiol (CBD) has demonstrated analgesic and anti-inflammatory effects in preclinical models of arthritis. In this open-label feasibility trial, participants with symptomatically active hand OA applied a novel transdermal CBD gel (4% w/w) three times a day for four weeks to their most painful hand. Changes in daily self-reported pain scores were measured on a 0-10 Numeric Pain Rating Scale (NPRS). Hand functionality was determined via daily grip strength measures using a Bluetooth equipped squeeze ball and self-report questionnaire. Quality of life (QoL) ratings around sleep, anxiety, stiffness and fatigue were also measured. All self-report measures and grip strength data were gathered via smartphone application. Urinalysis was conducted at trial end to determine systemic absorption of CBD. Eighteen participants were consented and 15 completed the trial. Pain ratings were significantly reduced over time from pre-treatment baseline including current pain (- 1.91 ± 0.35, p < 0.0001), average pain (- 1.92 ± 0.35, p < 0.0001) and maximum pain (- 1.97 ± 0.34, p < 0.0001) (data represent mean reduction on a 0-10 NPRS scale ± standard error of the mean (SEM)). A significant increase in grip strength in the treated hand (p < 0.0001) was observed although self-reported functionality did not improve. There were significant (p < 0.005) improvements in three QoL measures: fatigue, stiffness and anxiety. CBD and its metabolites were detected at low concentrations in all urine samples. Measured reductions in pain and increases in grip strength seen during treatment reverted back towards baseline during the washout phase. In summary, pain, grip strength and QoL measures, using smartphone technology, was shown to improve over time following transdermal CBD application suggesting feasibility of this intervention in relieving osteoarthritic hand pain. Proof of efficacy, however, requires further confirmation in a placebo-controlled randomised trial.Trial registration: ANZCTR public trials registry (ACTRN12621001512819, 05/11/2021).

Nanosuspension-Loaded Dissolving Microneedle Patches for Enhanced Transdermal Delivery of a Highly Lipophilic Cannabidiol

Purpose

Transdermal Drug Delivery System (TDDS) offers a promising alternative for delivering poorly soluble drugs, challenged by the stratum corneum's barrier effect, which restricts the pool of drug candidates suitable for TDDS. This study aims to establish a delivery platform specifically for highly lipophilic drugs requiring high doses (log P > 5, dose > 10 mg/kg/d), to improve their intradermal delivery and enhance solubility.

Methods

Cannabidiol (CBD, log P = 5.91) served as the model drug. A CBD nanosuspension (CBD-NS) was prepared using a bottom-up method. The particle size, polydispersity index (PDI), zeta potential, and concentration of the CBD-NS were characterized. Subsequently, CBD-NS was incorporated into dissolving microneedles (DMNs) through a one-step manufacturing process. The intradermal dissolution abilities, physicochemical properties, mechanical strength, insertion depth, and release behavior of the DMNs were evaluated. Sprague-Dawley (SD) rats were utilized to assess the efficacy of the DMN patch in treating knee synovitis and to analyze its skin permeation kinetics and pharmacokinetic performance.

Results

The CBD-NS, stabilized with Tween 80, exhibited a particle size of 166.83 ± 3.33 nm, a PDI of 0.21 ± 0.07, and a concentration of 46.11 ± 0.52 mg/mL. The DMN loaded with CBD-NS demonstrated favorable intradermal dissolution and mechanical properties. It effectively increased the delivery of CBD into the skin, extended the action's duration in vivo, and enhanced bioavailability. CBD-NS DMN exhibited superior therapeutic efficacy and safety in a rat model of knee synovitis, significantly inhibiting TNF-α and IL-1β compared with the methotrexate subcutaneous injection method.

Conclusion

NS technology effectively enhances the solubility of the poorly soluble drug CBD, while DMN facilitates penetration, extends the duration of action in vivo, and improves bioavailability. Furthermore, CBD has shown promising therapeutic outcomes in treating knee synovitis. This innovative drug delivery system is expected to offer a more efficient solution for the administration of highly lipophilic drugs akin to CBD, thereby facilitating high-dose administration.

An evaluation of the cannabinoid content of the liquid and thermal degradation analysis of cannabis-labeled vape liquids

Cannabidiol (CBD) vape pen usage has been on the rise given the changing political and scientific climate as well as the promotion of these delivery systems as a more accessible and lower-risk option for consumers. Despite being marketed as a safer way to use cannabis, CBD vape liquids are sold without restrictions or meticulous quality control procedures such as toxicological and clinical assessment, standards for product preservation, or investigative degradation analyses. Nine CBD-labeled vape liquid samples purchased and manufactured in the United States were evaluated and assessed for cannabinoid content. Quantification and validation of cannabinoids and matrix components was accomplished using gas and liquid chromatography with mass spectrometry analysis (GC-MS and LC-MS/MS) following liquid-liquid extraction with methanol. Samples degraded by temperature (analyzed by GC-MS) showed a greater disparity from the labeled CBD content compared with samples analyzed as purchased (by LC-MS/MS). Thermal degradation of the vape liquids showed increased levels of tetrahydrocannabinol (THC). Also, extended time and temperature degradation were evaluated in vape liquids by storing them for 15 months and then varying temperature conditions before analysis, which indicated CBD transformed into other cannabinoids leading to different cannabinoid content within the vape samples. Evaluation conducted on these vape liquids indicated the route of exposure, storage conditions, and length of storage could expose consumers to unintended cannabinoids and showed a concerning level of disagreement between the products' labeled cannabinoid content and the results generated by these analyses.

Effectiveness of cannabidiol (CBD) on histopathological changes and gene expression in hepatocellular carcinoma (HCC) model in male rats: the role of Hedgehog (Hh) signaling pathway

The third most prevalent malignancy to cause mortality is hepatocellular carcinoma (HCC). The Hedgehog (Hh) signaling pathway is activated by binding to the transmembrane receptor Patched-1 (PTCH-1), which depresses the transmembrane G protein-coupled receptor Smoothened (SMO). This study was performed to examine the preventative and therapeutic effects of cannabidiol in adult rats exposed to diethyl nitrosamine (DENA)-induced HCC.A total of 50 male rats were divided into five groups of 10 rats each. Group I was the control group. Group II received intraperitoneal (IP) injections of DENA for 14 weeks. Group III included rats that received cannabidiol (CBD) orally (3-30 mg/kg) for 2 weeks and DENA injections for 14 weeks. Group IV rats received oral CBD for 2 weeks before 14 weeks of DENA injections. Group V included rats that received CBD orally for 2 weeks after their last injection of DENA. Measurements were made for alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and alpha fetoprotein (AFP). Following total RNA extraction, Smo, Hhip, Ptch-1, and Gli-1 expressions were measured using quantitative real-time polymerase chain reaction (qRT-PCR). A histopathological analysis of liver tissues was performed.The liver enzymes, oxidant-antioxidant state, morphological, and molecular parameters of the adult male rat model of DENA-induced HCC showed a beneficial improvement after CBD administration. In conclusion, by focusing on the Hh signaling system, administration of CBD showed a beneficial improvement in the liver enzymes, oxidant-antioxidant status, morphological, and molecular parameters in the DENA-induced HCC in adult male rats.

Permeation-Enhancing Strategies for Transdermal Delivery of Cannabinoids

Introduction: This review aims to provide an overview of the advancements and status of clinical studies and potential permeation-enhancing strategies in the transdermal delivery of cannabinoids. Methods: A systematic and comprehensive literature search across academic databases, search engines, and online sources to identify relevant literature on the transdermal administration of cannabinoids. Results: Cannabinoids have proven beneficial in the treatment of wide-ranging physical and psychological disorders. A shift toward legalized cannabinoid products has increased both interests in cannabinoid research and the development of novel medicinal exploitations of cannabinoids in recent years. Oral and pulmonary delivery of cannabinoids has several limitations, including poor bioavailability, low solubility, and potential side effects. This has diverted scientific attention toward the transdermal route, successfully overcoming these hurdles by providing higher bioavailability, safety, and patient compliance. Yet, due to the barrier properties of the skin and the lipophilic nature of cannabinoids, there is a need to increase the permeation of the drugs to the underneath layers of skin to reach desired therapeutic plasma levels. Literature describing detailed clinical trials on cannabinoid transdermal delivery, either with or without permeation-enhancing strategies, is limited. Conclusion: The limited number of reports indicates that increased attention is needed on developing and examining efficient transdermal delivery systems for cannabinoids, including patch design and composition, drug-patch interaction, clinical effectiveness and safety in vivo, and permeation-enhancing strategies.

Cannabinoids for the treatment of autoimmune and inflammatory skin diseases: A systematic review

In recent years, the medical use of cannabinoids has attracted growing attention worldwide. In particular, anti-inflammatory properties of cannabinoids led to their emergence as potential therapeutic options for autoimmune and inflammatory disorders. Recent studies have also shown that cannabinoid receptors are widely expressed and have endogenous ligands in the skin, suggesting that the skin has its own endocannabinoid system. The aim of this review is to discuss the potential therapeutic effects of cannabinoids in autoimmune and inflammatory skin diseases. Following an overview of cannabinoids and the endocannabinoid system, we describe the cellular and molecular mechanisms of cannabinoids in skin health and disease. We then review the clinical studies of cannabinoids in autoimmune and inflammatory skin diseases including systemic sclerosis (SSc), dermatomyositis (DM), psoriasis (Pso) and atopic dermatitis (AD). A primary literature search was conducted in July 2023, using PubMed and Web of Science. A total of 15 articles were included after excluding reviews, non-human studies and in vitro studies from 389 non-duplicated articles. Available evidence suggests that cannabinoids may be beneficial for SSc, DM, Pso and AD. However, further studies, ideally randomized controlled trials, are needed to further evaluate the use of cannabinoids in autoimmune and inflammatory skin diseases.

Unveiling the Potential of Cannabinoids in Multiple Sclerosis and the Dawn of Nano-Cannabinoid Medicine

Multiple sclerosis is the predominant autoimmune disorder affecting the central nervous system in adolescents and adults. Specific treatments are categorized as disease-modifying, whereas others are symptomatic treatments to alleviate painful symptoms. Currently, no singular conventional therapy is universally effective for all patients across all stages of the illness. Nevertheless, cannabinoids exhibit significant promise in their capacity for neuroprotection, anti-inflammation, and immunosuppression. This review will examine the traditional treatment for multiple sclerosis, the increasing interest in using cannabis as a treatment method, its role in protecting the nervous system and regulating the immune system, commercially available therapeutic cannabinoids, and the emerging use of cannabis in nanomedicine. In conclusion, cannabinoids exhibit potential as a disease-modifying treatment rather than merely symptomatic relief. However, further research is necessary to unveil their role and establish the safety and advancements in nano-cannabinoid medicine, offering the potential for reduced toxicity and fewer adverse effects, thereby maximizing the benefits of cannabinoids.

Improved quality of life and pain relief in mature horses with osteoarthritis after oral transmucosal cannabidiol oil administration as part of an analgesic regimen

The aim of this study was to evaluate the effect of oral cannabidiol (CBD) administration in addition to a conventional analgesic protocol on the clinical signs of 20 horses with mild joint osteoarthritis. The horses were randomly assigned to either the control group (C group) or the cannabidiol group (CBD group). Both groups were treated with phenylbutazone for 5 days. The CBD group received 0.03 mg/kg cannabidiol in hemp oil orally once daily for 14 days in addition to phenylbutazone treatment. All subjects were monitored for clinical parameters, oxidative status and blood counts. Pain and quality of life were also assessed using the Horse Chronic Pain Scale (HCPS). The CBD group showed a significant reduction in heart rate, respiratory rate, white blood cell count and oxidative stress (malondialdehyde lipid peroxidation). A significant reduction in HCPS scores was seen in both groups. Lower scores were recorded in the CBD group (3 med; range: 2/4) than in the C group (7 med; range: 4/10). The addition of a cannabidiol-based product to an analgesic protocol was well tolerated and showed positive effects on the treated subjects, improving their quality of life and pain relief.

The Therapeutic Potential and Molecular Mechanisms Underlying the Neuroprotective Effects of Sativex® - A Cannabis-derived Spray

Sativex is a cannabis-based medicine that comes in the form of an oromucosal spray. It contains equal amounts of Δ9-tetrahydrocannabinol and cannabidiol, two compounds derived from cannabis plants. Sativex has been shown to have positive effects on symptoms of amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), and sleep disorders. It also has analgesic, antiinflammatory, antitumoral, and neuroprotective properties, which make it a potential treatment option for other neurological disorders. The article reviews the results of recent preclinical and clinical studies that support the therapeutic potential of Sativex and the molecular mechanisms behind its neuroprotective benefits in various neurological disorders. The article also discusses the possible advantages and disadvantages of using Sativex as a neurotherapeutic agent, such as its safety, efficacy, availability, and legal status.

Cannabinoids and the Endocannabinoid System in Early SARS-CoV-2 Infection and Long COVID-19-A Scoping Review

Coronavirus disease-19 (COVID-19) is a highly contagious illness caused by the SARS-CoV-2 virus. The clinical presentation of COVID-19 is variable, often including symptoms such as fever, cough, headache, fatigue, and an altered sense of smell and taste. Recently, post-acute "long" COVID-19 has emerged as a concern, with symptoms persisting beyond the acute infection. Vaccinations remain one of the most effective preventative methods against severe COVID-19 outcomes and the development of long-term COVID-19. However, individuals with underlying health conditions may not mount an adequate protective response to COVID-19 vaccines, increasing the likelihood of severe symptoms, hospitalization, and the development of long-term COVID-19 in high-risk populations. This review explores the potential therapeutic role of cannabinoids in limiting the susceptibility and severity of infection, both pre- and post-SARS-CoV-19 infection. Early in the SARS-CoV-19 infection, cannabinoids have been shown to prevent viral entry, mitigate oxidative stress, and alleviate the associated cytokine storm. Post-SARS-CoV-2 infection, cannabinoids have shown promise in treating symptoms associated with post-acute long COVID-19, including depression, anxiety, post-traumatic stress injury, insomnia, pain, and decreased appetite. While current research primarily focuses on potential treatments for the acute phase of COVID-19, there is a gap in research addressing therapeutics for the early and post-infectious phases. This review highlights the potential for future research to bridge this gap by investigating cannabinoids and the endocannabinoid system as a potential treatment strategy for both early and post-SARS-CoV-19 infection.

Cannabis as a Source of Approved Drugs: A New Look at an Old Problem

Cannabis plants have been used in medicine since ancient times. They are well known for their anti-diabetic, anti-inflammatory, neuroprotective, anti-cancer, anti-oxidative, anti-microbial, anti-viral, and anti-fungal activities. A growing body of evidence indicates that targeting the endocannabinoid system and various other receptors with cannabinoid compounds holds great promise for addressing multiple medical conditions. There are two distinct avenues in the development of cannabinoid-based drugs. The first involves creating treatments directly based on the components of the cannabis plant. The second involves a singular molecule strategy, in which specific phytocannabinoids or newly discovered cannabinoids with therapeutic promise are pinpointed and synthesized for future pharmaceutical development and validation. Although the therapeutic potential of cannabis is enormous, few cannabis-related approved drugs exist, and this avenue warrants further investigation. With this in mind, we review here the medicinal properties of cannabis, its phytochemicals, approved drugs of natural and synthetic origin, pitfalls on the way to the widespread clinical use of cannabis, and additional applications of cannabis-related products.

Efficacy and safety of medical cannabinoids in children with cerebral palsy: a systematic review

INTRODUCTION

The increasing popularity of cannabinoids for treating numerous neurological disorders has been reported in various countries. Although it reduces tetrahydrocannabinol psychoactivity, it helps patients tolerate higher doses and complements the anti-spasmodic effects of tetrahydrocannabinol. One of the most important potential of cannabinoids are related to its potential to help children with cerebral palsy, a contributor of lifelong disability. Therefore, this systematic review aimed to assess the efficacy and safety of medical cannabinoids in children with cerebral palsy.

METHODS

This review adhered to The Preferred Reporting Items for Systematic Reviews and Meta-analysis 2020 guidelines. Seven databases, namely, Scopus, PubMed, EBSCO Host, ProQuest, Google Scholar, Semantic Scholar, and JSTOR, were used to identify relevant studies. Studies examining pediatric patients with cerebral palsy and reporting the efficacy and safety of medical cannabinoids through clinical trials, observational cross-sectional studies, or cohort designs were included. The outcomes of the studies included the efficacy of medical cannabinoids administered for spasticity, motor components, pain control, sleep difficulties, adverse effects, and seizure control.

RESULTS

Of 803 identified articles, only three met the inclusion criteria for data synthesis. One study exhibited a moderate risk-of-bias. A total of 133 respondents, mainly from Europe, were investigated. Overall effectiveness and safety were considered good. However, the results are inconsistent, especially regarding spasticity treatment variables.

CONCLUSION

The anti-spasticity, anti-inflammatory, and anti-seizure properties of cannabinoids might be beneficial for patients with cerebral palsy, although their effectiveness has not been widely studied. Further studies with larger sample sizes and various ethnicities are warranted. Prospero database registration: (www.crd.york.ac.uk/prospero) under ID CRD42022358383.

Topical Cannabidiol and the Progression Rate of Delayed Onset Muscle Soreness

This study investigated the efficacy of topical cannabidiol (CBD) ointment in reducing localized inflammation, minimizing performance detriments, and attenuating soreness associated with delayed onset muscle soreness (DOMS). In a double blind randomized control trial, upper-arm circumferences, maximal voluntary isometric contractions (MVICs) for elbow flexion at 90° and 30° for college-aged participants (n = 21, age 20.8 ± 1.9 years) were assessed at baseline. Participants then performed a DOMS-inducing protocol for the biceps brachii. Topical CBD ointment and placebo (P) ointment were randomly assigned and applied 30 minutes, 24, 48 and 72 hours post the DOMS protocol. The baseline parameters and a visual analog scale (VAS) to assess perceived soreness were assessed 24, 48 and 72 hours post DOMS protocol. A 4x2 repeated measures factorial ANOVA (P < 0.05) analyzed both within and between subject differences. No changes were statistically significant on any days between conditions: Upper-arm circumferences in the CBD arm (7.1 ± 5.8 cm) and in the P arm (7.3 ± 5.8 cm). MVICs were reduced at both the 90° and 30° positions (-5.9 ± 9.0 Nm (90°)); (-4.8 ± 6.5 Nm (30°)) and the P arm (-5.0 ± 10.0 Nm (90°)); (-4.6 ± 5.3 Nm (30°)). Soreness increased in both the CBD arm (6.1 ± 2.1) and the P arm (5.5 ± 2.6) over time. Topical CBD therefore did not alter any parameters vs the P treatment, thus the use of topical CBD does not attenuate the effects of DOMS.

Phytocannabinoids: Pharmacological effects, biomedical applications, and worldwide prospection

Scientific evidence exists about the association between neurological diseases (i.e., Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis (ALS), multiple sclerosis, depression, and memory loss) and oxidative damage. The increasing worldwide incidence of such diseases is attracting the attention of researchers to find palliative medications to reduce the symptoms and promote quality of life, in particular, in developing countries, e.g., South America and Africa. Among potential alternatives, extracts of Cannabis Sativa L. are suitable for people who have neurological disorders, spasticity, and pain, nausea, resulting from diseases such as cancer and arthritis. In this review, we discuss the latest developments in the use of Cannabis, its subtypes and constituents, extraction methods, and relevant pharmacological effects. Biomedical applications, marketed products, and prospects for the worldwide use of Cannabis Sativa L. extracts are also discussed, providing the bibliometric maps of scientific literature published in representative countries from South America (i.e., Brazil) and Africa (i.e., South Africa). A lack of evidence on the effectiveness and safety of Cannabis, besides the concerns about addiction and other adverse events, has led many countries to act with caution before changing Cannabis-related regulations. Recent findings are expected to increase the social acceptance of Cannabis, while new technologies seem to boost the global cannabis market because the benefits of (-)-trans-delta-9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) use have been proven in several studies in addition to the potential to general new employment.

Investigation of Cannabinoid Acid/Cyclodextrin Inclusion Complex for Improving Physicochemical and Biological Performance

This study aimed to investigate the enhancement of cannabinoid acid solubility and stability through the formation of a cannabinoid acid/cyclodextrin (CD) inclusion complex. Two cannabinoid acids, tetrahydro-cannabinolic acid (THCA) and cannabidiolic acid (CBDA), were selected as a model drug along with five types of CD: α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), γ-cyclodextrin (γ-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD), and methylated-β-cyclodextrin (M-β-CD). Phase solubility studies were conducted using various types of CD to determine the complex stoichiometry. The preparation methods of the CD inclusion complex were optimized by adjusting the loading pH solution and the drying processes (spray-drying, freeze-drying, spray-freeze-drying). The drying process of the cannabinoid acid/M-β-CD inclusion complex was further optimized through the spray-freeze-drying method. These CD complexes were characterized using solubility determination, differential scanning calorimetry (DSC), field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and 1H NMR spectroscopy. DSC, XRD, and FE-SEM studies confirmed the non-crystalline state of the cannabinoid acid/CD inclusion complex. The permeation of THCA or CBDA from the M-β-CD spray-freeze-dried inclusion complex was highly improved compared to those of cannabis ethanolic extracts under simulated physiological conditions. The stability of the cannabinoid acid/M-β-CD inclusion complex was maintained for 7 days in a simulated physiological condition. Furthermore, the minimum inhibitory concentration of cannabinoid acid/M-β-CD inclusion complex had superior anti-cancer activity in MCF-7 breast cancer cell lines compared to cannabinoid acid alone. The improved physicochemical and biological performances indicated that these CD inclusion complexes could provide a promising option for loading lipophilic cannabinoids in cannabis-derived drug products.

Evaluating Sex Differences in Efficacy, Safety and Pharmacokinetics in Patients Treated with Cannabis by a Metered-Dose Inhaler

BACKGROUND

Clinical studies on medical cannabis (MC) treatment have shown sex-related differences, including higher susceptibility to adverse events among women and greater analgesia among men. Here, we used the Syqe metered-dose inhaler (MDI) and a single chemovar to analyze sex differences.

METHODS

A total of 1249 Israeli chronic pain patients were assessed for pain intensity, sleep and adverse events (AEs) over 240 days.

RESULTS

Following the first two weeks, no significant sex differences were found in the effectiveness or safety of MC treatment (p > 0.05). Inhaled Δ9-THC doses did not vary significantly between sexes (p > 0.05) except in the first month of treatment. Pain reduction and sleep improvement were similar for both sexes (p > 0.05). The overall rate of AEs was equal and relatively low at 10% (n = 65, 10% of women and n = 60, 10% of men; χ2 (1) = 0.05, p = 0.820). A secondary analysis of pharmacokinetic data showed no significant differences between sexes in Δ9-THC and its metabolite pharmacokinetics, cardiovascular measures, or AE severity (p > 0.05).

CONCLUSIONS

Uniform MC treatment via the Syqe MDI showed no sex differences in short-term effectiveness, safety and pharmacokinetics, nor in long-term effects, under "real-life" conditions. These findings provide insights into MC treatment which may inform clinical practice and policy-making in the field.

Population Pharmacokinetics of Oral-Based Administration of Cannabidiol in Healthy Adults: Implications for Drug Development

Background and Objectives: Cannabidiol (CBD) is increasingly being studied as a therapeutic option for a range of health conditions; however, the pharmacokinetics of CBD is not well understood. This study characterized CBD pharmacokinetics in healthy adults using a population pharmacokinetic approach, informing drug development of oral-based dose forms of CBD. Materials and Methods: CBD concentration-time data were obtained from a phase I, randomized, open-label, four-way crossover study (n=12) and modeled using Phoenix NLME. Monte Carlo simulations were conducted to estimate CBD exposure with chronic dosing as intended for clinical use (50 mg b.i.d.). Results: A three-compartment pharmacokinetic model with a chain of absorption transit compartments and first-order elimination most adequately described CBD pharmacokinetics. Substantial variability in population pharmacokinetic parameters was identified (up to 60%CV), which could not be accounted for by any covariates. Simulations indicated a 3.6-fold difference in drug exposure at steady state with multiple dosing (AUCτ 95% prediction interval: 65.5-138 ng·h/mL), and variability in the time to reach steady state, which was predicted to be up to ∼3 weeks in some individuals (95% prediction interval: 18.6-297 h). Conclusions: The findings of this study have important implications for drug development. The lack of a clear dose-response relationship, due to large pharmacokinetic variability, indicates that a one-size-fits-all approach to CBD dosing may not be feasible, at least with current dosing approaches. Furthermore, an extended time to reach steady state means that the full effect of a selected dose level is not truly observed for some time and requires careful consideration in trial design.

Current Challenges and Opportunities for Improved Cannabidiol Solubility

Cannabidiol (CBD), derived from the cannabis plant, has gained significant attention due to its potential therapeutic benefits. However, one of the challenges associated with CBD administration is its low bioavailability, which refers to the fraction of an administered dose that reaches systemic circulation. This limitation necessitates the exploration of various approaches to enhance the bioavailability of CBD, thus helping to maximize its therapeutic potential. A variety of approaches are now emerging, including nanoemulsion-based systems, lipid-based formulations, prodrugs, nanocarriers, and alternative routes of administration, which hold promise for improving the bioavailability of CBD and pave the way for novel formulations that maximize the therapeutic potential of CBD in various medical conditions. This opinion piece presents the current understanding surrounding CBD bioavailability and considers strategies aimed at improving both its absorption and its bioavailability.

Co-Dispersion Delivery Systems with Solubilizing Carriers Improving the Solubility and Permeability of Cannabinoids (Cannabidiol, Cannabidiolic Acid, and Cannabichromene) from Cannabis sativa (Henola Variety) Inflorescences

Cannabinoids: cannabidiol (CBD), cannabidiolic acid (CBDA), and cannabichromene (CBC) are lipophilic compounds with limited water solubility, resulting in challenges related to their bioavailability and therapeutic efficacy upon oral administration. To overcome these limitations, we developed co-dispersion cannabinoid delivery systems with the biopolymer polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol (Soluplus) and magnesium aluminometasilicate (Neusilin US2) to improve solubility and permeability. Recognizing the potential therapeutic benefits arising from the entourage effect, we decided to work with an extract instead of isolated cannabinoids. Cannabis sativa inflorescences (Henola variety) with a confirming neuroprotective activity were subjected to dynamic supercritical CO2 (scCO2) extraction and next they were combined with carriers (1:1 mass ratio) to prepare the co-dispersion cannabinoid delivery systems (HiE). In vitro dissolution studies were conducted to evaluate the solubility of CBD, CBDA, and CBC in various media (pH 1.2, 6.8, fasted, and fed state simulated intestinal fluid). The HiE-Soluplus delivery systems consistently demonstrated the highest dissolution rate of cannabinoids. Additionally, HiE-Soluplus exhibited the highest permeability coefficients for cannabinoids in gastrointestinal tract conditions than it was during the permeability studies using model PAMPA GIT. All three cannabinoids exhibited promising blood-brain barrier (BBB) permeability (Papp higher than 4.0 × 10-6 cm/s), suggesting their potential to effectively cross into the central nervous system. The improved solubility and permeability of cannabinoids from the HiE-Soluplus delivery system hold promise for enhancement in their bioavailability.

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.

Endocannabinoid basis of personality-Insights from animal model of social behavior

Rationale: The endocannabinoid system is known to be involved in learning, memory, emotional processing and regulation of personality patterns. Here we assessed the endocannabinoid profile in the brains of mice with strong characteristics of social dominance and submissiveness. Methods: A lipidomics approach was employed to assess the endocannabinoidome in the brains of Dominant (Dom) and Submissive (Sub) mice. The endocannabinoid showing the greatest difference in concentration in the brain between the groups, docosatetraenoyl ethanolamine (DEA), was synthesized, and its effects on the physiological and behavioral responses of Dom and Sub mice were evaluated. mRNA expression of the endocannabinoid receptors and enzymes involved in PUFA biosynthesis was assessed using qRT-PCR. Results: Targeted LC/MS analysis revealed that long-chain polyunsaturated ethanolamides including arachidonoyl ethanolamide (AEA), DEA, docosatrienoyl ethanolamide (DTEA), eicosatrienoyl ethanolamide (ETEA), eicosapentaenoyl ethanolamide (EPEA) and docosahexaenoyl ethanolamide (DHEA) were higher in the Sub compared with the Dom mice. Untargeted LC/MS analysis showed that the parent fatty acids, docosatetraenoic (DA) and eicosapentaenoic (EPA), were higher in Sub vs. Dom. Gene expression analysis revealed increased mRNA expression of genes encoding the desaturase FADS2 and the elongase ELOVL5 in Sub mice compared with Dom mice. Acute DEA administration at the dose of 15 mg/kg produced antinociceptive and locomotion-inducing effects in Sub mice, but not in Dom mice. Subchronic treatment with DEA at the dose of 5 mg/kg augmented dominant behavior in wild-type ICR and Dom mice but not in Sub mice. Conclusion: This study suggests that the endocannabinoid system may play a role in the regulation of dominance and submissiveness, functional elements of social behavior and personality. While currently we have only scratched the surface, understanding the role of the endocannabinoid system in personality may help in revealing the mechanisms underlying the etiopathology of psychiatric disorders.

The Skin and Natural Cannabinoids-Topical and Transdermal Applications

The chemical constituents of the Cannabis plant known as cannabinoids have been extensively researched for their potential therapeutic benefits. The use of cannabinoids applied to the skin as a potential method for both skin-related benefits and systemic administration has attracted increasing interest in recent years. This review aims to present an overview of the most recent scientific research on cannabinoids used topically, including their potential advantages for treating a number of skin conditions like psoriasis, atopic dermatitis, and acne. Additionally, with a focus on the pharmacokinetics and security of this route of administration, we investigate the potential of the transdermal delivery of cannabinoids as a method of systemic administration. The review also discusses the restrictions and difficulties related to the application of cannabinoids on the skin, emphasizing the potential of topical cannabinoids as a promising route for both localized and systemic administration. More studies are required to fully comprehend the efficacy and safety of cannabinoids in various settings.

Should oncologists trust cannabinoids?

Cannabis enjoyed a "golden age" as a medicinal product in the late 19th, early 20th century, but the increased risk of overdose and abuse led to its criminalization. However, the 21st century have witnessed a resurgence of interest and a large body of literature regarding the benefits of cannabinoids have emerged. As legalization and decriminalization have spread around the world, cancer patients are increasingly interested in the potential utility of cannabinoids. Although eager to discuss cannabis use with their oncologist, patients often find them to be reluctant, mainly because clinicians are still not convinced by the existing evidence-based data to guide their treatment plans. Physicians should prescribe cannabis only if a careful explanation can be provided and follow up response evaluation ensured, making it mandatory for them to be up to date with the positive and also negative aspects of the cannabis in the case of cancer patients. Consequently, this article aims to bring some clarifications to clinicians regarding the sometimes-confusing various nomenclature under which this plant is mentioned, current legislation and the existing evidence (both preclinical and clinical) for the utility of cannabinoids in cancer patients, for either palliation of the associated symptoms or even the potential antitumor effects that cannabinoids may have.

Atorvastatin-loaded pro-nanolipospheres with ameliorated oral bioavailability and antidyslipidemic activity

Despite significant advances in oral drug delivery technologies, many drugs are prone to limited oral bioavailability due to biological barriers that hinder drug absorption. Pro-nanolipospheres (PNL) are a form of delivery system that can potentiate the oral bioavailability of poorly water-soluble drugs through a variety of processes, including increased drug solubility and protecting them from degradation by intestinal or hepatic first-pass metabolism. In this study, pro-nanolipospheres were employed as a delivery vehicle for improving the oral bioavailability of the lipophilic statin, atorvastatin (ATR). Various ATR-loaded PNL formulations, composed of various pharmaceutical ingredients, were prepared by the pre-concentrate method and characterized by determining particle size, surface charge, and encapsulation efficiency. An optimized formula (ATR-PT PNL) showing the smallest particle size, highest zeta potential, and highest encapsulation efficiency was selected for further in vivo investigations. The in vivo pharmacodynamic experiments demonstrated that the optimized ATR-PT PNL formulation exerted a potent hypolipidemic effect in a Poloxamer® 407-induced hyper-lipidaemia rat model by restoring normal cholesterol and triglyceride serum levels along with alleviating serum levels of LDL while elevating serum HDL levels, compared to pure drug suspensions and marketed ATR (Lipitor®). Most importantly, oral administration of the optimized ATR-PT PNL formulation showed a dramatic increase in ATR oral bioavailability, as evinced by a 1.7- and 3.6-fold rise in systemic bioavailability when compared with oral commercial ATR suspensions (Lipitor®) and pure drug suspension, respectively. Collectively, pro-nanolipospheres might represent a promising delivery vehicle for enhancing the oral bioavailability of poorly water-soluble drugs.

Therapeutic targeting of the tumor microenvironments with cannabinoids and their analogs: Update on clinical trials

Cancer is a major global public health concern that affects both industrialized and developing nations. Current cancer chemotherapeutic options are limited by side effects, but plant-derived alternatives and their derivatives offer the possibilities of enhanced treatment response and reduced side effects. A plethora of recently published articles have focused on treatments based on cannabinoids and cannabinoid analogs and reported that they positively affect healthy cell growth and reverse cancer-related abnormalities by targeting aberrant tumor microenvironments (TMEs), lowering tumorigenesis, preventing metastasis, and/or boosting the effectiveness of chemotherapy and radiotherapy. Furthermore, TME modulating systems are receiving much interest in the cancer immunotherapy field because it has been shown that TMEs have significant impacts on tumor progression, angiogenesis, invasion, migration, epithelial to mesenchymal transition, metastasis and development of drug resistance. Here, we have reviewed the effective role of cannabinoids, their analogs and cannabinoid nano formulations on the cellular components of TME (endothelial cells, pericytes, fibroblast and immune cells) and how efficiently it retards the progression of carcinogenesis is discussed. The article summarizes the existing research on the molecular mechanisms of cannabinoids regulation of the TME and finally highlights the human studies on cannabinoids' active interventional clinical trials. The conclusion outlines the need for future research involving clinical trials of cannabinoids to demonstrate their efficacy and activity as a treatment/prevention for various types of human malignancies.

Cannabidiol for the Treatment of Brain Disorders: Therapeutic Potential and Routes of Administration

The use of cannabidiol (CBD) for treating brain disorders has gained increasing interest. While the mechanism of action of CBD in these conditions is still under investigation, CBD has been shown to affect numerous different drug targets in the brain that are involved in brain disorders. Here we review the preclinical and clinical evidence on the potential therapeutic use of CBD in treating various brain disorders. Moreover, we also examine various drug delivery approaches that have been applied to CBD. Due to the slow absorption and low bioavailability with the current oral CBD therapy, more efficient routes of administration to bypass hepatic metabolism, particularly pulmonary delivery, should be considered. Comparison of pharmacokinetic studies of different delivery routes highlight the advantages of intranasal and inhalation drug delivery over other routes of administration (oral, injection, sublingual, buccal, and transdermal) for treating brain disorders. These two routes of delivery, being non-invasive and able to achieve fast absorption and increase bioavailability, are attracting increasing interest for CBD applications, with more research and development expected in the near future.

The endocannabinoid system, a new gatekeeper in the pharmacology of human hepatocellular carcinoma

Despite numerous prevention methodologies and treatment options, hepatocellular carcinoma (HCC) still remains as the third leading life-threatening cancer. It is thus pertinent to develop new treatment modality to fight this devastating carcinoma. Ample recent studies have shown the anti-inflammatory and antitumor roles of the endocannabinoid system in various forms of cancers. Preclinical studies have also confirmed that cannabinoid therapy can be an optimal regimen for cancer treatments. The endocannabinoid system is involved in many cancer-related processes, including induction of endoplasmic reticulum (ER) stress-dependent apoptosis, autophagy, PITRK and ERK signaling pathways, cell invasion, epithelial-mesenchymal transition (EMT), and cancer stem cell (CSC) phenotypes. Moreover, changes in signaling transduction of the endocannabinoid system can be a potential diagnostic and prognostic biomarker for HCC. Due to its pivotal role in lipid metabolism, the endocannabinoid system affects metabolic reprogramming as well as lipid content of exosomes. In addition, due to the importance of non-coding RNAs (ncRNAs), several studies have examined the relationship between microRNAs and the endocannabinoid system in HCC. However, HCC is a pathological condition with high heterogeneity, and therefore using the endocannabinoid system for treatment has faced many controversies. While some studies favored a role of the endocannabinoid system in carcinogenesis and tumor induction, others exhibited the anticancer potential of endocannabinoids in HCC. In this review, specific studies delineating the relationship between endocannabinoids and HCC are examined. Based on collected findings, detailed studies of the molecular mechanism of endocannabinoids as well as preclinical studies for investigating therapeutic or carcinogenic impacts in HCC cancer are strongly suggested.

An update of nano-based drug delivery systems for cannabinoids: Biopharmaceutical aspects & therapeutic applications

Nanotechnology has been widely used to improve stability, efficacy, release control and biopharmaceutical aspects of natural and synthetic cannabinoids. In this review, the main types of cannabinoid-based nanoparticles (NPs) reported so far are addressed, taking into account the advantages and disadvantages of each system. Formulation, preclinical and clinical studies performed with colloidal carriers were individually analyzed. Lipid-based nanocarriers have been recognized for their high biocompatibility and ability to improve both solubility and bioavailability. Δ⁹-tetrahydrocannabinol-loaded lipid systems designed to treat glaucoma, for example, showed superior in vivo efficacy in comparison to market formulations. The analyzed studies have shown that product performance can be modulated by varying particle size and composition. In the case of self-nano-emulsifying drug delivery systems, the reduced particle size shortens the time to reach high plasma concentrations while the incorporation of metabolism inhibitors extends the plasma circulation time. The use of long alkyl chain lipids in NP formulations, in turn, is strategized to achieve intestinal lymphatic absorption. Polymer NPs have been prioritized when a sustained or site-specific cannabinoid release is desirable (e.g., CNS-affecting diseases/cancer). The functionalization of the surface of polymer NPs makes their action even more selective whereas surface charge modulation is highlighted to provide mucoadhesion. The present study identified promising systems for targeted applications, making the process of optimizing new formulations more effective and faster. Although NPs have shown a promising role in the treatment of several difficult-to-treat diseases, more translational studies should be performed to confirm the benefits reported here.

N-type calcium channel blockers: a new approach towards the treatment of chronic neuropathic pain

Neuropathic pain (NP) remains maltreated for a wide number of patients by the currently available treatments and little research has been done in finding new drugs for treating NP. Ziconotide (PrialtTM) had been developed as the new drug, which belongs to the class of ω-conotoxin MVIIA. It inhibits N-type calcium channels. Ziconotide is under the last phase of the clinical trial, a new non-narcotic drug for the management of NP. Synthetically it has shown the similarities with ω-conotoxin MVIIA, a constituent of poison found in fish hunting snails (Conus magus). Ziconotide acts by selectively blocking neural N-type voltage-sensitized Ca2+ channels (NVSCCs). Certain herbal drugs also have been studied but no clinical result is there and the study is only limited to preclinical data. This review emphasizes the N-type calcium channel inhibitors, and their mechanisms for blocking calcium channels with their remedial prospects for treating chronic NP.

The antinociceptive activity and mechanism of action of cannabigerol

Cannabis has been used for centuries to treat pain. The antinociceptive activity of tetrahydrocannabinol (THC) or cannabidiol (CBD) has been widely studied. However, the antinociceptive effects of other cannabis components, such as cannabichromene (CBC) and cannabigerol (CBG), have rarely been revealed. The antinociceptive mechanism of CBG is not yet clear, so we investigated the antinociceptive effect of CBG on different pain models, and explored the mechanism of action of CBG to exert antinociceptive effects. In the current study, we compared the antinociceptive effects of CBC, CBD, and CBG on the carrageenan-induced inflammatory pain model in mice, and the results showed that CBG had a better antinociceptive effects through intraplantar administration. On this basis, we further investigated the antinociceptive effect of CBG on CIA-induced arthritis pain model and nerve pain model in mice, and found that CBG also relieved on both types of pain. Then, we explored the antinociceptive mechanism of CBG, which revealed that CBG can activate TRPV1 and desensitize it to block the transmission of pain signals. In addition, CBG can further activate CB2R, but not CB1R, to stimulate the release of β-endorphin, which greatly promotes the antinociceptive effect. Finally, the safety test results showed that CBG had no irritating effect on the rabbits' skin, and it did not induce significant biochemical and hematological changes in mice. Transdermal delivery results also indicated that CBG has certain transdermal properties. Overall, this study indicates that CBG is promising for developing a transdermal dosage for pain management.

Neuropathic pain: Mechanisms and therapeutic strategies

The physiopathology and neurotransmission of pain are of an owe inspiring complexity. Our ability to satisfactorily suppress neuropathic or other forms of chronic pain is limited. The number of pharmacodynamically distinct and clinically available medications is low and the successes achieved modest. Pain Medicine practitioners are confronted with the ethical dichotomy imposed by Hippocrates: On one hand the mandate of primum non nocere, on the other hand, the promise of heavenly joys if successful divinum est opus sedare dolorem. We briefly summarize the concepts associated with nociceptive pain from nociceptive input (afferents from periphery), modulatory output [descending noradrenergic (NE) and serotoninergic (5-HT) fibers] to local control. The local control is comprised of the "inflammatory soup" at the site of pain origin and synaptic relay stations, with an ATP-rich environment promoting inflammation and nociception while an adenosine-rich environment having the opposite effect. Subsequently, we address the transition from nociceptor pain to neuropathic pain (independent of nociceptor activation) and the process of sensitization and pain chronification (transient pain progressing into persistent pain). Having sketched a model of pain perception and processing we attempt to identify the sites and modes of action of clinically available drugs used in chronic pain treatment, focusing on adjuvant (co-analgesic) medication.

Exploring the Potential of Cannabinoid Nanodelivery Systems for CNS Disorders

Cannabinoids have a major therapeutic value in a variety of disorders. The concepts of cannabinoids are difficult to develop, but they can be used and are advantageous for a number of diseases that are not sufficiently managed by existing treatments. Nanoconjugation and encapsulation techniques have been shown to be effective in improving the delivery and the therapeutic effectiveness of drugs that are poorly soluble in water. Because the bioavailability of cannabinoids is low, the challenge is to explore different administration methods to improve their effectiveness. Because cannabinoids cross the blood-brain-barrier (BBB), they modify the negative effects of inflammatory processes on the BBB and may be a key factor in the improvement of BBB function after ischemic disease or other conditions. This review discusses various types of cannabinoid administration, as well as nanotechnologies used to improve the bioavailability of these compounds in CNS diseases.

Cannabinoids as Prospective Anti-Cancer Drugs: Mechanism of Action in Healthy and Cancer Cells

Endogenous and exogenous cannabinoids modulate many physiological and pathological processes by binding classical cannabinoid receptors 1 (CB1) or 2 (CB2) or non-cannabinoid receptors. Cannabinoids are known to exert antiproliferative, apoptotic, anti-migratory and anti-invasive effect on cancer cells by inducing or inhibiting various signaling cascades. In this chapter, we specifically emphasize the latest research works about the alterations in endocannabinoid system (ECS) components in malignancies and cancer cell proliferation, migration, invasion, angiogenesis, autophagy, and death by cannabinoid administration, emphasizing their mechanism of action, and give a future perspective for clinical use.

Examining the Systemic Bioavailability of Cannabidiol and Tetrahydrocannabinol from a Novel Transdermal Delivery System in Healthy Adults: A Single-Arm, Open-Label, Exploratory Study

INTRODUCTION

Transdermal cannabinoids may provide better safety and bioavailability profiles compared with other routes of administration. This single-arm, open-label study investigated a novel topical transdermal delivery system on the pharmacokinetics of cannabidiol (CBD) and tetrahydrocannabinol (THC).

METHODS

Participants were 39.5 ± 7.37 years old and healthy, based on a review by the Medical Director. Blood was collected pre-dose and 10, 20, 30, and 45 min, and 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8, and 12 h after topical application of 100 mg CBD:100 mg THC. Psychoactive effects were assessed prior to each timepoint. Area-under-the-curve (AUC_0-12 h), maximum concentration (C_max), time to maximum concentration (T_max), area-under-the-curve to infinity (AUC_I), terminal elimination rate constant (λ), terminal half-life (t½), and absorption rate constant (k_a) were measured individually for CBD and THC. Safety was assessed by clinical chemistry, hematology, and adverse events.

RESULTS

AUC_0-12 h for CBD and THC was 3329.8 ± 3252.1 and 2093.4 ± 2090.6 pg/mL/h, with C_max of 576.52 ± 1016.18 and 346.57 ± 776.85 pg/mL, respectively. T_max for CBD and THC was 8 h, ranging from 2.5 h to 12 h and 10 min to 12 h, respectively. AUC_I for CBD and THC was 6609.2 ± 7056.4 and 3721.0 ± 3251.7 pg/mL/h, with t_1/2 of 5.68 ± 1.5 and 5.38 ± 1.25 h, respectively. CBD was absorbed at a faster rate compared with THC (123.36 ± 530.97 versus 71.5 ± 1142.19 h^-1) but with similar λ (0.12 ± 0.029 versus 0.13 ± 0.03 h^-1). No psychoactive effects were reported. Transdermal cannabinoid delivery was safe and well tolerated in the population studied.

CONCLUSION

To our knowledge, this is the first pharmacokinetic study in humans that demonstrated CBD and THC entering systemic circulation via transdermal administration . This study represents an important contribution to understanding the pharmacokinetics of transdermal cannabinoids.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier-NCT05121506 (November 16, 2021).

Cannabis Bioactive Compound-Based Formulations: New Perspectives for the Management of Orofacial Pain

The management of orofacial pain to alleviate the quality of life of affected patients is becoming increasingly challenging for scientific research and healthcare professionals. From this perspective, in addition to conventional therapies, new alternatives are being sought, increasingly looking at the use of both natural and synthetic products. Cannabis sativa L. represents an interesting source of bioactive compounds, including non-psychoactive cannabinoids, flavonoids, and terpenes, many of which are effective in improving pain intensity. Here, we aim to analyze the possible mechanisms of action of the bioactive natural and synthetic hemp-derived compounds responsible for the modulatory effects on pain-related pathways. The ability of these compounds to act on multiple mechanisms through a synergistic effect, reducing both the release of inflammatory mediators and regulating the response of the endocannabinoid system, makes them interesting agents for alternative formulations to be used in orofacial pain.

A reliable quantitative method for determining CBD content and release from transdermal patches in Franz cells

INTRODUCTION

There are several cannabidiol (CBD) transdermal patches available on the market. However, none are FDA-approved. Furthermore, not much evidence has been published about CBD release and skin permeation from such patches, so the effectiveness and reliability remain unclear.

OBJECTIVES

We aimed to develop a method to determine the in vitro release and skin permeation of CBD from transdermal patches using Franz cell diffusion in combination with quantitative ¹ H-NMR (qNMR).

MATERIALS AND METHODS

The study was conducted on CBD patches with known CBD content and six different commercially available or market-ready CBD patches using a Franz cell with a Strat-M™ membrane and with samples taken directly from the transdermal patch for qNMR analysis.

RESULTS

The use of qNMR yielded an average recovery of 100% ± 7% when samples with known CBD content were tested. Results from the testing of six commercially available patches indicated that five out of six patches did not contain the CBD amount stated by the manufacturer according to a ± 10% variance margin, of which four patches were under-labeled and one was over-labeled. The release rate of patches was determined, and significant differences between the patches were shown. Maximum release of CBD was calculated to occur after 39 to 70 h.

CONCLUSION

The established method was proven to be a reliable means of determining the quantity and release of CBD from transdermal patches and can be used to verify CBD content and release rate in transdermal patches.

Cannabinoids for Pain Modulation in Orthopedic Surgery

Cannabinoid compounds are being increasingly used as an analgesic adjuvant in the orthopedic population, but little data exist to either support or oppose this practice pattern. A review of all contemporary (2000-2020) studies on the use of cannabinoids in orthopedics is presented. Physicians and patients are optimistic that cannabinoids can decrease pain scores and perhaps opioid use; however, their application in orthopedics is not well characterized. In addition to the social stigma regarding the use of cannabis, there is limited high-quality evidence of the efficacy of cannabinoids in treating orthopedic-related pain. As cannabis becomes more accessible, well-designed trials are needed to better understand cannabinoids and guide orthopedic practice. [Orthopedics. 2022;45(6):e295-e302.].

Recent Advances in Endocannabinoid System Targeting for Improved Specificity: Strategic Approaches to Targeted Drug Delivery

Opportunities for developing innovative and intelligent drug delivery technologies by targeting the endocannabinoid system are becoming more apparent. This review provides an overview of strategies to develop targeted drug delivery using the endocannabinoid system (ECS). Recent advances in endocannabinoid system targeting showcase enhanced pharmaceutical therapy specificity while minimizing undesirable side effects and overcoming formulation challenges associated with cannabinoids. This review identifies advances in targeted drug delivery technologies that may permit access to the full pharmacotherapeutic potential of the ECS. The design of optimized nanocarriers that target specific tissues can be improved by understanding the nature of the signaling pathways, distribution in the mammalian body, receptor structure, and enzymatic degradation of the ECS. A closer look at ligand-receptor complexes, endocannabinoid tone, tissue distribution, and G-protein activity leads to a better understanding of the potential of the ECS toolkit for therapeutics. The signal transduction pathways examine the modulation of downstream effector proteins, desensitization, signaling cascades, and biased signaling. An in-depth and overall view of the targeted system is achieved through homology modeling where mutagenesis and ligand binding examine the binding site and allow sequence analysis and the formation of libraries for molecular docking and molecular dynamic simulations. Internalization routes exploring receptor-mediated endocytosis and lipid rafts are also considered for explicit signaling. Furthermore, the review highlights nanotechnology and surface modification aspects as a possible future approach for specific targeting.

Pilot clinical and pharmacokinetic study of Δ9-Tetrahydrocannabinol (THC)/Cannabidiol (CBD) nanoparticle oro-buccal spray in patients with advanced cancer experiencing uncontrolled pain

This pilot study aimed to assess the safety, tolerability, pharmacokinetics and exploratory analgesic effect of a novel water-soluble oro-buccal nanoparticle spray of a cannabis-based medicine (MDCNS-01) in patients with advanced incurable malignancy with unrelieved pain from opioid analgesic. The study was a non-blinded single arm 2 stage study. Stage I was a single escalating dose (n = 5) [2.5 mg Δ9-THC and 2.5 mg CBD) versus a 3-fold escalated dose. Stage II was an up-titrated dose in patients with advanced cancers and intractable pain (n = 25). During Stage I with an increased cannabis-based medicine dose, maximum observed plasma concentrations of cannabinoids were dose dependant. The water-soluble formulation in the current study resulted in a higher median (min, max) systemic exposure of Δ9-THC than CBD (AUC from 2.5 mg each of Δ9-THC and CBD, was 1.71 ng mL.h-1 (1.1, 6.6) and 0.65 ng mL.h-1 (0.49, 4.1), respectively). During stage II a subgroup of patients diagnosed with breast and prostate cancers with bone metastases, had the highest mean pain score improvement from baseline of 40% (unadjusted) and 33% (adjusted for rescue medication use). For all patients the most reported adverse events were mild or moderate drowsiness affecting 11 (44%) and 4 (6%) patients, respectively, and nausea and vomiting that affected 18 (72%) patients. The water-soluble cannabis-based medicine provided acceptable bioavailability for Δ9-THC/CBD, appeared safe and tolerable in advanced incurable cancers with uncontrolled pain with preliminary evidence of analgesic efficacy.

Positive Allosteric Modulators of Glycine Receptors and Their Potential Use in Pain Therapies

Glycine receptors are ligand-gated ion channels that mediate synaptic inhibition throughout the mammalian spinal cord, brainstem, and higher brain regions. They have recently emerged as promising targets for novel pain therapies due to their ability to produce antinociception by inhibiting nociceptive signals within the dorsal horn of the spinal cord. This has greatly enhanced the interest in developing positive allosteric modulators of glycine receptors. Several pharmaceutical companies and research facilities have attempted to identify new therapeutic leads by conducting large-scale screens of compound libraries, screening new derivatives from natural sources, or synthesizing novel compounds that mimic endogenous compounds with antinociceptive activity. Advances in structural techniques have also led to the publication of multiple high-resolution structures of the receptor, highlighting novel allosteric binding sites and providing additional information for previously identified binding sites. This has greatly enhanced our understanding of the functional properties of glycine receptors and expanded the structure activity relationships of novel pharmacophores. Despite this, glycine receptors are yet to be used as drug targets due to the difficulties in obtaining potent, selective modulators with favorable pharmacokinetic profiles that are devoid of side effects. This review presents a summary of the structural basis for how current compounds cause positive allosteric modulation of glycine receptors and discusses their therapeutic potential as analgesics. SIGNIFICANCE STATEMENT: Chronic pain is a major cause of disability, and in Western societies, this will only increase as the population ages. Despite the high level of prevalence and enormous socioeconomic burden incurred, treatment of chronic pain remains limited as it is often refractory to current analgesics, such as opioids. The National Institute for Drug Abuse has set finding effective, safe, nonaddictive strategies to manage chronic pain as their top priority. Positive allosteric modulators of glycine receptors may provide a therapeutic option.

Nano-Enabled Chronic Wound Healing Strategies: Burn and Diabetic Ulcer Wounds

The human skin serves as the body’s first line of defense against the environment. Diabetes mellitus (DM) and 2nd–4th degree burns, on the other hand, affect the skin’s protective barrier features. Burn wounds, hypermetabolic state, and hyperglycemia compromise the immune system leading to chronic wound healing. Unlike acute wound healing processes, chronic wounds are affected by reinfections which can lead to limb amputation or death. The conventional wound dressing techniques used to protect the wound and provide an optimal environment for repair have their limitations. Various nanomaterials have been produced that exhibit distinct features to tackle issues affecting wound repair mechanisms. This review discusses the emerging technologies that have been designed to improve wound care upon skin injury. To ensure rapid healing and possibly prevent scarring, different nanomaterials can be applied at different stages of healing (hemostasis, inflammation, proliferation, remodeling).