Lipid nanocapsules decorated and loaded with cannabidiol as targeted prolonged release carriers for glioma therapy: In vitro screening of critical parameters

From bench to bedside: the application of cannabidiol in glioma

Glioma is the most common malignant tumor in central nervous system, with significant health burdens to patients. Due to the intrinsic characteristics of glioma and the lack of breakthroughs in treatment modalities, the prognosis for most patients remains poor. This results in a heavy psychological and financial load worldwide. In recent years, cannabidiol (CBD) has garnered widespread attention and research due to its anti-tumoral, anti-inflammatory, and neuroprotective properties. This review comprehensively summarizes the preclinical and clinical research on the use of CBD in glioma therapy, as well as the current status of nanomedicine formulations of CBD, and discusses the potential and challenges of CBD in glioma therapy in the future.

Demystifying the potential of lipid-based nanocarriers in targeting brain malignancies

Drug targeting for brain malignancies is restricted due to the presence of the blood-brain barrier (BBB) and blood-brain tumor barrier (BBTB), which act as barriers between the blood and brain parenchyma. Certainly, the limited therapeutic options for brain malignancies have made notable progress with enhanced biological understanding and innovative approaches, such as targeted therapies and immunotherapies. These advancements significantly contribute to improving patient prognoses and represent a promising shift in the landscape of brain malignancy treatments. A more comprehensive understanding of the histology and pathogenesis of brain malignancies is urgently needed. Continued research focused on unraveling the intricacies of brain malignancy biology holds the key to developing innovative and tailored therapies that can improve patient outcomes. Lipid nanocarriers are highly effective drug delivery systems that significantly improve their solubility, bioavailability, and stability while also minimizing unwanted side effects. Surface-modified lipid nanocarriers (liposomes, niosomes, solid lipid nanoparticles, nanostructured lipid carriers, lipid nanocapsules, lipid-polymer hybrid nanocarriers, lipoproteins, and lipoplexes) are employed to improve BBB penetration and uptake through various mechanisms. This systematic review illuminates and covers various topics related to brain malignancies. It explores the different methods of drug delivery used in treating brain malignancies and delves into the benefits, limitations, and types of brain-targeted lipid-based nanocarriers. Additionally, this review discusses ongoing clinical trials and patents related to brain malignancy therapies and provides a glance into future perspectives for treating this condition.

Brain targeted lactoferrin coated lipid nanocapsules for the combined effects of apocynin and lavender essential oil in PTZ induced seizures

Apocynin (APO) is a plant derived antioxidant exerting specific NADPH oxidase inhibitory action substantiating its neuroprotective effects in various CNS disorders, including epilepsy. Due to rapid elimination and poor bioavailability, treatment with APO is challenging. Correspondingly, novel APO-loaded lipid nanocapsules (APO-LNC) were formulated and coated with lactoferrin (LF-APO-LNC) to improve br ain targetability and prolong residence time. Lavender oil (LAV) was incorporated into LNC as a bioactive ingredient to act synergistically with APO in alleviating pentylenetetrazol (PTZ)-induced seizures. The optimized LF-APO-LAV/LNC showed a particle size 59.7 ± 4.5 nm with narrow distribution and 6.07 ± 1.6mV zeta potential) with high entrapment efficiency 92 ± 2.4% and sustained release (35% in 72 h). Following subcutaneous administration, LF-APO-LAV/LNC brought about ⁓twofold increase in plasma AUC and MRT compared to APO. A Log BB value of 0.2 ± 0.14 at 90 min reflects increased brain accumulation. In a PTZ-induced seizures rat model, LF-APO-LAV/LNC showed a Modified Racine score of 0.67 ± 0.47 with a significant increase in seizures latency and decrease in duration. Moreover, oxidant/antioxidant capacity and inflammatory markers levels in brain tissue were significantly improved. Histopathological and immunohistochemical assessment of brain tissue sections further supported these findings. The results suggest APO/LAV combination in LF-coated LNC as a promising approach to counteract seizures.

Anti-Cancer and Anti-Proliferative Potential of Cannabidiol: A Cellular and Molecular Perspective

Cannabinoids, the bioactive compounds found in Cannabis sativa, have been used for medicinal purposes for centuries, with early discoveries dating back to the BC era (BCE). However, the increased recreational use of cannabis has led to a negative perception of its medicinal and food applications, resulting in legal restrictions in many regions worldwide. Recently, cannabinoids, notably Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), have gained renewed interest in the medical field due to their anti-cancer properties. These properties include the inhibition of tumour growth and cell invasion, anti-inflammatory effects, and the induction of autophagy and apoptosis. As a result, the use of cannabinoids to treat chemotherapy-associated side effects, like nausea, vomiting, and pain, has increased, and there have been suggestions to implement the large-scale use of cannabinoids in cancer therapy. However, these compounds' cellular and molecular mechanisms of action still need to be fully understood. This review explores the recent evidence of CBD's efficacy as an anti-cancer agent, which is of interest due to its non-psychoactive properties. The current review will also provide an understanding of CBD's common cellular and molecular mechanisms in different cancers. Studies have shown that CBD's anti-cancer activity can be receptor-dependent (CB1, CB2, TRPV, and PPARs) or receptor-independent and can be induced through molecular mechanisms, such as ceramide biosynthesis, the induction of ER stress, and subsequent autophagy and apoptosis. It is projected that these molecular mechanisms will form the basis for the therapeutic applications of CBD. Therefore, it is essential to understand these mechanisms for developing and optimizing pre-clinical CBD-based therapies.

Development and characterization of lipid nanocapsules loaded with iron oxide nanoparticles for magnetic targeting to the blood-brain barrier

Brain drug delivery is severely hindered by the presence of the blood-brain barrier (BBB). Its functionality relies on the interactions of the brain endothelial cells with additional cellular constituents, including pericytes, astrocytes, neurons, or microglia. To boost brain drug delivery, nanomedicines have been designed to exploit distinct delivery strategies, including magnetically driven nanocarriers as a form of external physical targeting to the BBB. Herein, a lipid-based magnetic nanocarrier prepared by a low-energy method is first described. Magnetic nanocapsules with a hydrodynamic diameter of 256.7 ± 8.5 nm (polydispersity index: 0.089 ± 0.034) and a ξ-potential of -30.4 ± 0.3 mV were obtained. Transmission electron microscopy-energy dispersive X-ray spectroscopy analysis revealed efficient encapsulation of iron oxide nanoparticles within the oily core of the nanocapsules. Both thermogravimetric analysis and phenanthroline-based colorimetric assay showed that the iron oxide percentage in the final formulation was 12 wt.%, in agreement with vibrating sample magnetometry analysis, as the specific saturation magnetization of the magnetic nanocapsules was 12% that of the bare iron oxide nanoparticles. Magnetic nanocapsules were non-toxic in the range of 50-300 μg/mL over 72 h against both the human cerebral endothelial hCMEC/D3 and Human Brain Vascular Pericytes cell lines. Interestingly, higher uptake of magnetic nanocapsules in both cell types was evidenced in the presence of an external magnetic field than in the absence of it after 24 h. This increase in nanocapsules uptake was also evidenced in pericytes after only 3 h. Altogether, these results highlight the potential for magnetic targeting to the BBB of our formulation.

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.

Strategies to Improve Cannabidiol Bioavailability and Drug Delivery

The poor physicochemical properties of cannabidiol (CBD) hamper its clinical development. The aim of this review was to examine the literature to identify novel oral products and delivery strategies for CBD, while assessing their clinical implications and translatability. Evaluation of the published literature revealed that oral CBD strategies are primarily focused on lipid-based and emulsion solutions or encapsulations, which improve the overall pharmacokinetics (PK) of CBD. Some emulsion formulations demonstrate more rapid systemic delivery. Variability in the PK effects of different oral CBD products is apparent across species. Several novel administration routes exist for CBD delivery that may offer promise for specific indications. For example, intranasal administration and inhalation allow quick delivery of CBD to the plasma and the brain, whereas transdermal and transmucosal administration routes deliver CBD systemically more slowly. There are limited but promising data on novel delivery routes such as intramuscular and subcutaneous. Very limited data show that CBD is generally well distributed across tissues and that some CBD products enable increased delivery of CBD to different brain regions. However, evidence is limited regarding whether changes in CBD PK profiles and tissue distribution equate to superior therapeutic efficacy across indications and whether specific CBD products might be suited to particular indications.

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.

Targeting the Endocannabinoid System Present in the Glioblastoma Tumour Microenvironment as a Potential Anti-Cancer Strategy

The highly aggressive and invasive glioblastoma (GBM) tumour is the most malignant lesion among adult-type diffuse gliomas, representing the most common primary brain tumour in the neuro-oncology practice of adults. With a poor overall prognosis and strong resistance to treatment, this nervous system tumour requires new innovative treatment. GBM is a polymorphic tumour consisting of an array of stromal cells and various malignant cells contributing to tumour initiation, progression, and treatment response. Cannabinoids possess anti-cancer potencies against glioma cell lines and in animal models. To improve existing treatment, cannabinoids as functionalised ligands on nanocarriers were investigated as potential anti-cancer agents. The GBM tumour microenvironment is a multifaceted system consisting of resident or recruited immune cells, extracellular matrix components, tissue-resident cells, and soluble factors. The immune microenvironment accounts for a substantial volume of GBM tumours. The barriers to the treatment of glioblastoma with cannabinoids, such as crossing the blood-brain barrier and psychoactive and off-target side effects, can be alleviated with the use of nanocarrier drug delivery systems and functionalised ligands for improved specificity and targeting of pharmacological receptors and anti-cancer signalling pathways. This review has shown the presence of endocannabinoid receptors in the tumour microenvironment, which can be used as a potential unique target for specific drug delivery. Existing cannabinoid agents, studied previously, show anti-cancer potencies via signalling pathways associated with the hallmarks of cancer. The results of the review can be used to provide guidance in the design of future drug therapy for glioblastoma tumours.

Lipid polymer hybrid nanoparticles: a custom-tailored next-generation approach for cancer therapeutics

Lipid-based polymeric nanoparticles are the highly popular carrier systems for cancer drug therapy. But presently, detailed investigations have revealed their flaws as drug delivery carriers. Lipid polymer hybrid nanoparticles (LPHNPs) are advanced core-shell nanoconstructs with a polymeric core region enclosed by a lipidic layer, presumed to be derived from both liposomes and polymeric nanounits. This unique concept is of utmost importance as a combinable drug delivery platform in oncology due to its dual structured character. To add advantage and restrict one's limitation by other, LPHNPs have been designed so to gain number of advantages such as stability, high loading of cargo, increased biocompatibility, rate-limiting controlled release, and elevated drug half-lives as well as therapeutic effectiveness while minimizing their drawbacks. The outer shell, in particular, can be functionalized in a variety of ways with stimuli-responsive moieties and ligands to provide intelligent holding and for active targeting of antineoplastic medicines, transport of genes, and theragnostic. This review comprehensively provides insight into recent substantial advancements in developing strategies for treating various cancer using LPHNPs. The bioactivity assessment factors have also been highlighted with a discussion of LPHNPs future clinical prospects.

Thymoquinone-loaded lipid nanocapsules with promising anticancer activity for colorectal cancer

Colorectal cancer (CRC) is the third most common worldwide. Depending on its stage, chemotherapy is usually given after surgery when CRC has already metastasized to other organs like the liver or lungs. Unfortunately, the current antineoplastics used for CRC therapies involve toxicity and side effects due to their lack of site-specificity. To overcome the drawbacks of heavy chemotherapy, this study proposes to assess the efficacy of thymoquinone (TQ), a bioactive constituent of black seeds (Nigella sativa), as an antiproliferative and pro-apoptotic agent on an experimental CRC model in mice. TQ was encapsulated in lipid nanocapsules (LNCs), used as nanocarriers, in order to increase its specificity and cell absorption. TQ-loaded LNCs (TQ-LNCs) have a diameter of 58.3 ± 3.7 nm and 87.7 ± 4.5% TQ encapsulation efficiency. In turn, in vivo studies showed that the intratumoral administration of TQ-LNCs decreased the tumor size in colorectal cancer bearing mice compared to the control group. TQ-LNCs were more effective than free TQ for inducing tumor cell death. These results highlight the potential of TQ entrapped in LNCs as an anticancer agent for CRC treatment.

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.

Multi-charged nanoemulsion for photodynamic treatment of glioblastoma cell line in 2D and 3D in vitro models

Multi-charged nanoemulsions (NE) were designed to deliver Cannabidiol (CBD), Indocyanine green (ICG), and Protoporphyrin (PpIX) to treat glioblastoma (GBM) through Photodynamic Therapy (PDT). The phase-inversion temperature (PIT) method resulted in a highly stable NE that can be scaled easily, with a six-month shelf-life. We observed the quasi-spherical morphology of the nanoemulsions without any unencapsulated material and that 89% (± 5.5%) of the material was encapsulated. All physicochemical properties were within the expected range for a nanostructured drug delivery system, making these multi-charged nanoemulsions promising for further research and development. NE-PIC (NE-Protoporphyrin + Indocyanine + CBD) was easily internalized on GBM cells after three hours of incubation. Nanoemulsion (NE and NE-PIC) did not result in significant cytotoxicity, even for GBM or non-tumorigenic cell lines (NHF). Phototoxicity was significantly higher for the U87MG cell than the T98G cell when exposed to: visible (430 nm) and infrared (810 nm) laser light, with a difference of about 20%. From 50 mJ.cm-2, the viability of GBM cell lines decreases significantly, ranging from 65% to 85%. The NE-PIC was also effective for inhibiting cell proliferation into a 3D spheroidal GBM cell model, which is promising for mimicking the tumor cell environment. Irradiation at 810 nm was more effective in treating spheroid due to its deeper penetration in complex structures. NE-PIC has the potential as a drug delivery system for photoinactivation and photo diagnostic of GBM cell lines, taking advantage of the versatility of its active components.

Current aspects of small extracellular vesicles in pain process and relief

Small extracellular vesicles (sEVs) have been identified as a noteworthy paracrine mechanism of intercellular communication in diagnosing and managing neurological disorders. Current research suggests that sEVs play a pivotal role in the pathological progression of pain, emphasizing their critical function in the pathological progression of pain in acute and chronic pain models. By facilitating the transfer of diverse molecules, such as proteins, nucleic acids, and metabolites, sEVs can modulate pain signaling transmission in both the central and peripheral nervous systems. Furthermore, the unique molecules conveyed by sEVs in pain disorders indicate their potential as diagnostic biomarkers. The application of sEVs derived from mesenchymal stem cells (MSCs) in regenerative pain medicine has emerged as a promising strategy for pain management. Moreover, modified sEVs have garnered considerable attention in the investigation of pathological processes and therapeutic interventions. This review presents a comprehensive overview of the current knowledge regarding the involvement of sEVs in pain pathogenesis and treatment. Nevertheless, additional research is imperative to facilitate their clinical implementation. Schematic diagram of sEVs in the biogenesis, signal transmission, diagnosis, and treatment of pain disorders. Small extracellular vesicles (sEVs) are secreted by multiple cells, loading with various biomolecules, such as miRNAs, transmembrane proteins, and amino acids. They selectively target other cells and regulating pain signal transmission. The composition of sEVs can serve as valuable biomarkers for pain diagnosis. In particular, mesenchymal stem cell-derived sEVs have shown promise as regenerative medicine for managing multiple pain disorders. Furthermore, by modifying the structure or contents of sEVs, they could potentially be used as a potent analgesic method.

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.

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.

Digestion behavior, in vitro and in vivo bioavailability of cannabidiol in emulsions stabilized by whey protein-maltodextrin conjugate: Impact of carrier oil

An emulsion delivery system may be affected significantly by oil phase composition in terms of digestion behavior and bioavailability of the delivered substance. In this study, emulsions loaded with cannabidiol (CBD) were prepared with medium chain triglyceride (MCT), long chain triglyceride (LCT) or MCT/LCT(1:1) as carrier oil and whey protein-maltodextrin conjugate as emulsifier, and the digestion behavior of emulsion and bioavailability of CBD were assessed in vitro and in vivo. The particle size of emulsions throughout the in vitro digestion process was in the order of MCT < MCT/LCT < LCT, and three emulsions showed consistent particle size changes: stable in oral phase, sharply increased in gastric phase, and decreased in small intestine. After intestinal digestion, about 90% of free fatty acids (FFA) was released in MCT emulsion, followed by MCT/LCT (76%) and then LCT (45%). CBD was degraded during gastrointestinal digestion and the transformation stability of CBD in oil phase was in the order of LCT > MCT/LCT > MCT. Although CBD had higher bioaccessibility in MCT and MCT/LCT emulsions, the bioavailability of CBD in LCT was the highest (43%), followed by MCT/LCT (39%), MCT (33%). In vivo pharmacokinetic study showed that MCT/LCT and LCT were more favorable for CBD transport and absorption. The results may provide useful information for the construction of delivery systems, protecting CBD molecules, and improving their bioavailability.

Evaluation of cannabidiol nanoparticles and nanoemulsion biodistribution in the central nervous system after intrathecal administration for the treatment of pain

We investigated how the biodistribution of cannabidiol (CBD) within the central nervous system (CNS) is influenced by two different formulations, an oil-in-water (O/W) nanoemulsion and polymer-coated nanoparticles (PCNPs). We observed that both CBD formulations administered were preferentially retained in the spinal cord, with high concentrations reaching the brain within 10 min of administration. The CBD nanoemulsion reached C_max in the brain at 210 ng/g within 120 min (T_max), whereas the CBD PCNPs had a C_max of 94 ng/g at 30 min (T_max), indicating that rapid brain delivery can be achieved through the use of PCNPs. Moreover, the AUC_0-4h of CBD in the brain was increased 3.7-fold through the delivery of the nanoemulsion as opposed to the PCNPs, indicating higher retention of CBD at this site. Both formulations exhibited immediate anti-nociceptive effects in comparison to the respective blank formulations.

Nanoformulations as a strategy to overcome the delivery limitations of cannabinoids

Medical cannabis has received significant interest in recent years due to its promising benefits in the management of pain, anxiety, depression and neurological and movement disorders. Specifically, the major phytocannabinoids derived from the cannabis plant such as (-) trans-Δ⁹ -tetrahydrocannabinol (THC) and cannabidiol (CBD), have been shown to be responsible for the pharmacological and therapeutic properties. Recently, these phytocannabinoids have also attracted special attention in cancer treatment due to their well-known palliative benefits in chemotherapy-induced nausea, vomiting, pain and loss of appetite along with their anticancer activities. Despite the enormous pharmacological benefits, the low aqueous solubility, high instability (susceptibility to extensive first pass metabolism) and poor systemic bioavailability restrict their utilization at clinical perspective. Therefore, drug delivery strategies based on nanotechnology are emerging to improve pharmacokinetic profile and bioavailability of cannabinoids as well as enhance their targeted delivery. Here, we critically review the nano-formulation systems engineered for overcoming the delivery limitations of native phytocannabinoids including polymeric and lipid-based nanoparticles (lipid nano capsules (LNCs), nanostructured lipid carriers (NLCs), nanoemulsions (NE) and self-emulsifying drug delivery systems (SEDDS)), ethosomes and cyclodextrins as well as their therapeutic applications.

Cannabidiol-Loaded Nanostructured Lipid Carriers (NLCs) for Dermal Delivery: Enhancement of Photostability, Cell Viability, and Anti-Inflammatory Activity

The aim of this study was to encapsulate cannabidiol (CBD) extract in nanostructured lipid carriers (NLCs) to improve the chemical stability and anti-inflammatory activity of CBD for dermal delivery. CBD-loaded NLCs (CBD-NLCs) were prepared using cetyl palmitate (CP) as a solid lipid and stabilized with Tego^® Care 450 (TG450) or poloxamer 188 (P188) by high-pressure homogenization (HPH). The CBD extract was loaded at 1% w/w. Three different oils were employed to produce CBD-NLCs, including Transcutol^® P, medium-chain triglycerides (MCT), and oleic acid (OA). CBD-NLCs were successfully prepared with an entrapment efficiency (E.E.) of 100%. All formulations showed particle sizes between 160 and 200 nm with PDIs less than 0.10. The type of surfactant and oil used affected the particle sizes, zeta potential, and crystallinity of the CBD-NLCs. CBD-NLCs stabilized with TG450 showed higher crystallinity after production and storage at 30 °C for 30 days as compared to those with P188. Encapsulation of the CBD extract in NLCs enhanced its chemical stability after exposure to simulated sunlight (1000 kJ/m²) compared to that of the CBD extract in ethanolic solution. The CBD-NLCs prepared from MCT and OA showed slower CBD release compared with that from Transcutol^® P, and the kinetic data for release of CBD from CBD-NLCs followed Higuchi's release model with a high coefficient of determination (>0.95). The extent of CBD permeation through Strat-M^® depended on the oil type. The cytotoxicity of the CBD extract on HaCaT and HDF cells was reduced by encapsulation in the NLCs. The anti-inflammatory activity of the CBD extract in RAW264.7 cell macrophages was enhanced by encapsulation in CBD-NLCs prepared from MCT and OA.

An Examination of the Anti-Cancer Properties of Plant Cannabinoids in Preclinical Models of Mesothelioma

Simple Summary

Mesothelioma is a deadly disease with few treatment options. Phytocannabinoids derived from the cannabis plant are garnering interest for their anti-cancer properties, however very little is known about their effects in mesothelioma. We aimed to assess whether phytocannabinoids have anti-cancer effects in mesothelioma and potential modes of action. We showed that several phytocannabinoids inhibited growth of mesothelioma cells, with two phytocannabinoids, cannabidiol (CBD) and cannabigerol (CBG), being the most potent. CBD and CBG also inhibited mesothelioma cell migration and invasion. Gene expression analysis highlighted signalling pathways that play a role in how CBD and CBG may exert their anti-cancer effects. CBD and CBG were unable to increase survival in a rat model of mesothelioma but this may be due to limitations in the drug delivery method.

Abstract

Mesothelioma is an aggressive cancer with limited treatment options and a poor prognosis. Phytocannabinoids possess anti-tumour and palliative properties in multiple cancers, however their effects in mesothelioma are unknown. We investigated the anti-cancer effects and potential mechanisms of action for several phytocannabinoids in mesothelioma cell lines. A panel of 13 phytocannabinoids inhibited growth of human (MSTO and H2452) and rat (II-45) mesothelioma cells in vitro, and cannabidiol (CBD) and cannabigerol (CBG) were the most potent compounds. Treatment with CBD or CBG resulted in G0/G1 arrest, delayed entry into S phase and induced apoptosis. CBD and CBG also significantly reduced mesothelioma cell migration and invasion. These effects were supported by changes in the expression of genes associated with the cell cycle, proliferation, and cell movement following CBD or CBG treatment. Gene expression levels of CNR1, GPR55, and 5HT1A also increased with CBD or CBG treatment. However, treatment with CBD or CBG in a syngeneic orthotopic rat mesothelioma model was unable to increase survival. Our data show that cannabinoids have anti-cancer effects on mesothelioma cells in vitro and alternatives of drug delivery may be needed to enhance their effects in vivo.

Cannabis as a potential compound against various malignancies, legal aspects, advancement by exploiting nanotechnology and clinical trials

Various preclinical and clinical studies exhibited the potential of cannabis against various diseases, including cancer and related pain. Subsequently, many efforts have been made to establish and develop cannabis-related products and make them available as prescription products. Moreover, FDA has already approved some cannabis-related products, and more advancement in this aspect is still going on. However, the approved product of cannabis is in oral dosage form, which exerts various limitations to achieve maximum therapeutic effects. A considerable translation is on a hike to improve bioavailability, and ultimately, the therapeutic efficacy of cannabis by the employment of nanotechnology. Besides the well-known psychotropic effects of cannabis upon the use at high doses, literature has also shown the importance of cannabis and its constituents in minimising the lethality of cancer in the preclinical models. This review discusses the history of cannabis, its legal aspect, safety profile, the mechanism by which cannabis combats with cancer, and the advancement of clinical therapy by exploiting nanotechnology. A brief discussion related to the role of cannabinoid in various cancers has also been incorporated. Lastly, the information regarding completed and ongoing trials have also been elaborated.

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

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

Enhanced Intramuscular Bioavailability of Cannabidiol Using Nanocrystals: Formulation, In Vitro Appraisal, and Pharmacokinetics

Cannabidiol (CBD) has poor water solubility and is subjected to extensive first-pass metabolism. These absorption obstacles are responsible for low and variable oral bioavailability of CBD. This study endeavored to improve CBD bioavailability by intramuscular (IM) injection of CBD nanocrystals (CBD-NC). The nanocrystals were prepared by antisolvent precipitation method and were characterized in terms of the particle size, polydispersity index (PDI), zeta potential, morphology, and crystalline status. CBD-NC displayed a particle size of 141.7±1.5 nm, a PDI of 0.18±0.01, and a zeta potential of -25.73 mV. CBD-NC freeze-dried powder using bovine serum albumin (BSA) as cryoprotectant had good redispersibility, and the average particle size was 139.1±1.4 nm after reconstitution. Moreover, these freeze-dried powders were characterized for drug loading and pH and were evaluated for in vitro dissolution and in vivo studies in a rat model. The in vivo results showed that AUC_{0-24 h} and C_max of CBD by IM injection of CBD nanocrystals increased significantly compared with that of oral (P.O) administration of CBD nanocrystals and CBD oil solution. This underlines the nano-sized CBD could be suggested as a practical and simple nanosystem for IM delivery with improved bioavailability. More importantly, these results pave the way for future development of CBD-NC retentive dosage forms. Graphical abstract.

QbD Approach towards Robust Design Space for Flutamide/PiperineSelf-Emulsifying Drug Delivery System with Reduced Liver Injury

Flutamide which is used to treat prostate cancer and other diseases induces liver damage during and after the therapy. The aim of this study was to develop a flutamide/piperineco-loaded self-emulsifying drug delivery system (FPSEDDS) to inhibit flutamide-induced liver injury by utilizing piperine as a metabolic inhibitor. The development of SEDDS was carried out following a quality by design (QbD) approach. The risk assessment study was performed to identify critical quality attributes (CQAs) and critical material attributes (CMAs)/critical process parameters (CPPs). I-optimal mixture design was executed with three CMAs as the independent variables and CQAs as the dependable variables. The effectiveness of optimized SEDDS to circumvent flutamide-induced hepatotoxicity was assessed in mice. The numerical optimization suggested an optimal formulation with a desirability value of 0.621, using CQAs targets as optimization goals with 95% prediction intervals (α = 0.05). The optimal formulation exhibited the grade A SEDDS characteristics with the guarantee of high payloads in self-formed oily droplets. The design space was also obtained from the same optimization goals. All CQA responses of verification points were found within the 95% prediction intervals of the polynomial models, indicating a good agreement between actual versus predicted responses within the design space. These obtained responses also passed CQAs acceptance criteria. Finally, hematoxylin-eosin staining revealed the minimal flutamide-induced hepatotoxicity from the optimal SEDDS formulation as compared to the control and flutamide/piperine normal suspension. We demonstrate that the piperine containing optimized SEDDS formulation developed by QbD significantly reduces the flutamide-induced liver injury in mice.

Cannabinoid Formulations and Delivery Systems: Current and Future Options to Treat Pain

The field of Cannabis sativa L. research for medical purposes has been rapidly advancing in recent decades and a growing body of evidence suggests that phytocannabinoids are beneficial for a range of conditions. At the same time impressing development has been observed for formulations and delivery systems expanding the potential use of cannabinoids as an effective medical therapy. The objective of this review is to present the most recent results from pharmaceutical companies and research groups investigating methods to improve cannabinoid bioavailability and to clearly establish its therapeutic efficacy, dose ranges, safety and also improve the patient compliance. Particular focus is the application of cannabinoids in pain treatment, describing the principal cannabinoids employed, the most promising delivery systems for each administration routes and updating the clinical evaluations. To offer the reader a wider view, this review discusses the formulation starting from galenic preparation up to nanotechnology approaches, showing advantages, limits, requirements needed. Furthermore, the most recent clinical data and meta-analysis for cannabinoids used in different pain management are summarized, evaluating their real effectiveness, in order also to spare opioids and improve patients' quality of life. Promising evidence for pain treatments and for other important pathologies are also reviewed as likely future directions for cannabinoids formulations.

Current trends on cannabidiol delivery systems: where are we and where are we going?

INTRODUCTION

Cannabidiol (CBD), a phytocannabinoid from Cannabis sativa, has several therapeutic properties. However, its high lipophilicity, metabolization, and instability impair its bioavailability and translational use in clinical settings. Several advanced drug delivery systems (ADDSs) have been evaluated as CBD carriers to overcome these drawbacks. These systems can improve the CBD dissolution profile, protect it against metabolization, and produce a site-specific release, increasing its bioavailability and making CBD administration clinically effective.

AREAS COVERED

This review summarizes scientific reports on cannabidiol advanced delivery systems (CBD-ADSs) that have been (i) developed, and (ii) applied therapeutically; reports published in the main scientific databases until January 2020 were included. Studies without experimental data and/or published in languages other than English were excluded. Moreover, pharmaceutical technology tools in CBD therapeutic use have been discussed, emphasizing the clinical translation of CBD carrier use.

EXPERT OPINION

Studies reporting CBD-ADS use for medicinal applications were reviewed and revealed multifaceted systems that can overcome the physicochemical drawbacks of CBD and improve its biological activities. Therefore, researchers concluded that the developed CBD-ADS can be used as an alternative to traditional formulations because they show comparable or superior effectiveness in treatment protocols. Although several criteria remain to be met, our findings emphasize the potential of CBD-ADSs for translational therapeutics, particularly for neurological-disorders.

Efficacy of cannabinoids against glioblastoma multiforme: A systematic review

INTRODUCTION

The increased incidence of Glioblastoma Multiforme, the most aggressive and most common primary brain tumour, is evident worldwide. Survival rates are reaching only 15 months due to its high recurrence and resistance to current combination therapies including oncotomy, radiotherapy and chemotherapy. Light has been shed in the recent years on the anticancer properties of cannabinoids from Cannabis sativa.

OBJECTIVE

To determine whether cannabinoids alone or in combination with radiotherapy and/or chemotherapy inhibit tumour progression, induce cancer cell death, inhibit metastasis and invasiveness and the mechanisms that underlie these actions.

METHOD

PubMed and Web of Science were used for a systemic search to find studies on the anticancer effects of natural cannabinoids on glioma cancer cells in vitro and/or in vivo.

RESULTS

A total of 302 papers were identified, of which 14 studies were found to fit the inclusion criteria. 5 studies were conducted in vitro, 2 in vivo and 7 were both in vivo and in vitro. 3 studies examined the efficacy of CBD, THC and TMZ, 1 study examined CBD and radiation, 2 studies examined efficacy of THC only and 3 studies examined the efficacy of CBD only. 1 study examined the efficacy of CBD, THC and radiotherapy, 2 studies examined the combination of CBD and THC and 2 more studies examined the efficacy of CBD and TMZ.

CONCLUSION

The evidence in this systematic review leads to the conclusion that cannabinoids possess anticancer potencies against glioma cells, however this effect varies with the combinations and dosages used. Studies so far were conducted on cells in culture and on mice as well as a small number of studies that were conducted on humans. Hence in order to have more accurate results, higher quality studies mainly including human clinical trials with larger sample sizes are necessitated urgently for GBM treatment.

Characterization of Biological Material Adsorption to the Surface of Nanoparticles without a Prior Separation Step: a Case Study of Glioblastoma-Targeting Peptide and Lipid Nanocapsules

Purpose

Current preclinical therapeutic strategies involving nanomedicine require increasingly sophisticated nanosystems and the characterization of the complexity of such nanoassemblies is becoming a major issue. Accurate characterization is often the factor that can accelerate the translational approaches of nanomedicines and their pharmaceutical development to reach the clinic faster. We conducted a case study involving the adsorption of the NFL-TBS.40–63 (NFL) peptide (derived from neurofilaments) to the surface of lipid nanocapsules (LNCs) (a combined nanosystem used to target glioblastoma cells) to develop an analytical approach combining the separation and the quantification in a single step, leading to the characterization of the proportion of free peptide and thus the proportion of peptide adsorbed to the lipid nanocapsule surface.

Methods

LNC suspensions, NFL peptide solution and LNC/NFL peptide mixtures were characterized using a Size-Exclusion Chromatography method (with a chromatographic apparatus). In addition, this method was compared to centrifugal-filtration devices, currently used in literature for this case study.

Results

Combining the steps for separation and characterization in one single sequence improved the accuracy and robustness of the data and led to reproducible results. Moreover the data deviation observed for the centrifugal-filtration devices demonstrated the limits for this increasingly used characterization approach, explained by the poor separation quality and highlighting the importance for the method optimization. The high potential of the technique was shown, proving that H-bond and/or electrostatic interactions mediate adsorption of the NFL peptide to the surface of LNCs.

Conclusions

Used only as a characterization tool, the process using chromatographic apparatus is less time and solvent consuming than classical Size-Exclusion Chromatography columns only used for separation. It could be a promising tool for the scientific community for characterizing the interactions of other combinations of nanosystems and active biological agents.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s11095-021-03034-8.

Cannabidiol (CBD) as a Promising Anti-Cancer Drug

Recently, cannabinoids, such as cannabidiol (CBD) and Δ9 -tetrahydrocannabinol (THC), have been the subject of intensive research and heavy scrutiny. Cannabinoids encompass a wide array of organic molecules, including those that are physiologically produced in humans, synthesized in laboratories, and extracted primarily from the Cannabis sativa plant. These organic molecules share similarities in their chemical structures as well as in their protein binding profiles. However, pronounced differences do exist in their mechanisms of action and clinical applications, which will be briefly compared and contrasted in this review. The mechanism of action of CBD and its potential applications in cancer therapy will be the major focus of this review article.

Cannabis sativa: Much more beyond Δ9-tetrahydrocannabinol

Cannabis is the most used illicit drug worldwide and its medicinal use is under discussion, being regulated in several countries. However, the psychotropic effects of Δ⁹-tetrahydrocannabinol (THC), the main psychoactive compound of Cannabis sativa, are of concern. Thus, the interest in the isolated constituents without psychotropic activity, such as cannabidiol (CBD) and cannabidivarin (CBDV) is growing. CBD and CBDV are lipophilic molecules with poor oral bioavailability and are mainly metabolized by cytochrome P450 (CYP450) enzymes. The pharmacodynamics of CBD is the best explored, being able to interact with diverse molecular targets, like cannabinoid receptors, G protein-coupled receptor-55, transient receptor potential vanilloid 1 channel and peroxisome proliferator-activated receptor-γ. Considering the therapeutic potential, several clinical trials are underway to study the efficacy of CBD and CBDV in different pathologies, such as neurodegenerative diseases, epilepsy, autism spectrum disorders and pain conditions. The anti-cancer properties of CBD have also been demonstrated by several pre-clinical studies in different types of tumour cells. Although less studied, CBDV, a structural analogue of CBD, is receiving attention in the last years. CBDV exhibits anticonvulsant properties and, currently, clinical trials are underway for the treatment of autism spectrum disorders. Despite the benefits of these phytocannabinoids, it is important to highlight their potential interference with relevant physiologic mechanisms. In fact, CBD interactions with CYP450 enzymes and with drug efflux transporters may have serious consequences when co-administered with other drugs. This review summarizes the therapeutic advances of CBD and CBDV and explores some aspects of their pharmacokinetics, pharmacodynamics and possible interactions. Moreover, it also highlights the therapeutic potential of CBD and CBDV in several medical conditions and clinical applications.

Dual-Purpose Materials Based on Carbon Xerogel Microspheres (CXMs) for Delayed Release of Cannabidiol (CBD) and Subsequent Aflatoxin Removal

The main objective of this study is to develop a novel dual-purpose material based on carbon xerogel microspheres (CXMs) that permits the delayed release of cannabidiol (CBD) and the removal of aflatoxin. The CXMs were prepared by the sol-gel method and functionalized with phosphoric acid (CXMP) and melamine (CXMN). The support and the modified materials were characterized by scanning electronic microscopy (SEM), N2 adsorption at -196 °C, X-ray photoelectron spectroscopy (XPS), and zeta potential. For the loading of the cannabidiol (CBD) in the porous samples, batch-mode adsorption experiments at 25 °C were performed, varying the concentration of CBD. The desorption kinetics was performed at two conditions for simulating the gastric (pH of 2.1) and intestinal (pH of 7.4) conditions at 37 °C based on in vitro CBD release. Posteriorly, the samples obtained after desorption were used to study aflatoxin removal, which was evaluated through adsorption experiments at pH = 7.4 and 37 °C. The adsorption isotherms of CBD showed a type I(b) behavior, with the adsorbed uptake being higher for the support than for the modified materials with P and N. Meanwhile, the desorption kinetics of CBD at gastric conditions indicated release values lower than 8%, and the remaining amount was desorbed at pH = 7.4 in three hours until reaching 100% based on the in vitro experiments. The results for aflatoxin showed total removal in less than 30 min for all the materials evaluated. This study opens a broader landscape in which to develop dual-purpose materials for the delayed release of CBD, improving its bioavailability and allowing aflatoxin removal in gastric conditions.

Cannabidiol Enhances the Passage of Lipid Nanocapsules across the Blood-Brain Barrier Both in Vitro and in Vivo

Diseases affecting the central nervous system (CNS) should be regarded as a major health challenge due to the current lack of effective treatments given the hindrance to brain drug delivery imposed by the blood-brain barrier (BBB). Since efficient brain drug delivery should not solely rely on passive targeting, active targeting of nanomedicines into the CNS is being explored. The present study is devoted to the development of lipid nanocapsules (LNCs) decorated with nonpsychotropic cannabinoids as pioneering nonimmunogenic brain-targeting molecules and to the evaluation of their brain-targeting ability both in vitro and in vivo. Noticeably, both the permeability experiments across the hCMEC/D3 cell-based in vitro BBB model and the biodistribution experiments in mice consistently demonstrated that the highest brain-targeting ability was achieved with the smallest-sized cannabinoid-decorated LNCs. Importantly, the enhancement in brain targeting achieved with the conjugation of cannabidiol to LNCs outperformed by 6-fold the enhancement observed for the G-Technology (the main brain active strategy that has already entered clinical trials for the treatment of CNS diseases). As the transport efficiency across the BBB certainly determines the efficacy of the treatments for brain disorders, small cannabinoid-decorated LNCs represent auspicious platforms for the design and development of novel therapies for CNS diseases.