Cannabidiol-rich non-psychotropic Cannabis sativa L. oils attenuate peripheral neuropathy symptoms by regulation of CB2-mediated microglial neuroinflammation.

Neuropathic pain (NP) is a chronic disease that affects the normal quality of life of patients. To date, the therapies available are only symptomatic and they are unable to reduce the progression of the disease. Many studies reported the efficacy of Cannabis sativa L. (C. sativa) on NP, but no Δ9 -tetrahydrocannabinol (Δ9 -THC)-free extracts have been investigated in detail for this activity so far. The principal aim of this work is to investigate the potential pain-relieving effect of innovative cannabidiol-rich non-psychotropic C. sativa oils, with a high content of terpenes (K2), compared to the same extract devoid of terpenes (K1). Oral administration of K2 (25 mg kg-1 ) induced a rapid and long-lasting relief of pain hypersensitivity in a mice model of peripheral neuropathy. In spinal cord samples, K2 reduced mitogen-activated protein kinase (MAPKs) levels and neuroinflammatory factors. These effects were reverted by the administration of a CB2 antagonist (AM630), but not by a CB1 antagonist (AM251). Conversely, K1 showed a lower efficacy in the absence of CB1/CB2-mediated mechanisms. In LPS-stimulated murine microglial cells (BV2), K2 reduced microglia pro-inflammatory phenotype through the downregulation of histone deacetylase 1 (HDAC-1) and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor (IKBα) and increased interleukin-10 (IL-10) expression, an important antiinflammatory cytokine. In conclusion, these results suggested that K2 oral administration attenuated NP symptoms by reducing spinal neuroinflammation and underline the important role of the synergism between cannabinoids and terpenes.

Application of experimental design in HPLC method optimisation for the simultaneous determination of multiple bioactive cannabinoids.

The scientific interest in Cannabis sativa L. analysis has been rapidly increasing in recent years, especially for what concerns cannabinoids, plant secondary metabolites which are well known for having many biological properties. High-performance liquid chromatography (HPLC) is frequently used for both the qualitative and quantitative analysis of cannabinoids in plant extracts from C. sativa and its derived products. Many studies have been focused on the main cannabinoids, such as ∆9-tetrahydrocannabinolic acid (∆9-THCA), cannabidiolic acid (CBDA), cannabigerolic acid (CBGA) and their decarboxylated derivatives, such as ∆9-tetrahydrocannabinol (∆9-THC), cannabidiol (CBD) and cannabigerol (CBG). In addition to the abovementioned compounds, the plant produces other metabolites of the same chemical class, and some of them have shown interesting biological activities. In the light of this, it is important to have efficient analytical methods for the simultaneous separation of cannabinoids, which is quite complex since they present similar chemical-physical characteristics. The present work is focused on the use of the Design of Experiments technique (DoE) to develop and optimise an HPLC method for the simultaneous separation of 14 cannabinoids. Experimental design optimisation was applied by using a Central Composite Face-Centered design to achieve the best resolution with minimum experimental trials. Five significant variables affecting the chromatographic separation, including ammonium formate concentration, gradient elution, run time and flow rate, were studied. A multivariate strategy, based on Principal Component Analysis (PCA) and Partial Least Squared (PLS) regression, was used to define the best operative conditions. The developed method allowed for the separation of 12 out of 14 cannabinoids. Due to co-elution phenomena, HPLC coupled with a triple quadrupole mass analyser (HPLC-ESI-MS/MS) was applied, monitoring the specific transitions of each compound in the multiple reaction monitoring (MRM) mode. Finally, the optimised method was applied to C. sativa extracts having a different cannabinoid profile to demonstrate its efficiency to real samples. The methodology applied in this study can be useful for the separation of other cannabinoid mixtures, by means of appropriate optimisation of the experimental conditions.

Chemical characterization of non-psychoactive Cannabis sativa L. extracts, in vitro antiproliferative activity and induction of apoptosis in chronic myelogenous leukaemia cancer cells.

In this study, extracts from non-psychoactive Cannabis sativa L. varieties were characterized by means of ultra high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS) and their antiproliferative activity was assessed in vitro. The human chronic myelogenous leukaemia cell line K562 was chosen to investigate the mechanism of cell death. The effect on the cell cycle and cell death was analysed by flow cytometry. Proteins related to apoptosis were studied by western blotting. Mechanical properties of cells were assessed using the Micropipette Aspiration Technique (MAT). The results indicated that the cannabidiol (CBD)-rich extract inhibited cell proliferation of K562 cell line in a dose-dependent manner and induced apoptosis via caspase 3 and 7 activation. A significant decrease in the mitochondrial membrane potential was detected, together with the release of cytochrome c into the cytosol. The main apoptotic markers were not involved in the mechanism of cell death. The extract was also able to modify the mechanical properties of cells. Thus, this hemp extract and its pure component CBD deserve further investigation for a possible application against myeloproliferative diseases, also in association with other anticancer drugs.

Separation and non-separation methods for the analysis of cannabinoids in Cannabis sativa L.

Cannabis sativa L. is a plant known all over the world, due to its history, bioactivity and also social impact. It is chemically complex with an astonishing ability in the biosynthesis of many secondary metabolites belonging to different chemical classes. Among them, cannabinoids are the most investigated ones, given their pharmacological relevance. In order to monitor the composition of the plant material and ensure the efficacy and safety of its derived products, extraction and analysis of cannabinoids play a crucial role. In this context, in addition to a conventional separation method based on HPLC with UV/DAD detection, a new strategy based on a non-separation procedure, such as 13C-qNMR, may offer several advantages, such as reduced solvent consumption and simultaneous acquisition of the quali/quantitative data related to many analytes. In the light of all the above, the aim of this work is to compare the efficiency of the above-mentioned analytical techniques for the study of the main cannabinoids in different samples of cannabis inflorescences, belonging to fibre-type, recreational and medical varieties. The 13C-qNMR method here proposed for the first time for the quantification of both psychoactive and non-psychoactive cannabinoids in different cannabis varieties provided reliable results in comparison to the more common and consolidated HPLC technique.

Innovative methods for the preparation of medical Cannabis oils with a high content of both cannabinoids and terpenes.

Cannabis-based medications are being increasingly used for the treatment of different clinical conditions. Among all galenic formulations, olive oil extracts from medical Cannabis are the most prescribed ones for their easy preparation and usage. A great variety of methods have been described so far for the extraction of medical Cannabis oils to reach a high yield of Δ9-tetrahydrocannabinol (Δ9-THC), but poor attention has been paid to the preservation of the terpene fraction from the plant, which may contribute to the overall bioactivity of the extracts. In this context, the present study was aimed at the chemical characterization of different medical Cannabis oils prepared by following both innovative and existing extraction protocols, with particular attention to cannabinoids and terpenes, in order to set up a suitable method to obtain an extract rich in these chemical classes. In particular, six different extraction procedures were followed, based on different techniques, of which all but one included a decarboxylation of the plant material. The profile of cannabinoids was studied in detail by means of HPLC-ESI-MS/MS, while terpenes were characterized by means both GC-MS and GC-FID techniques coupled with solid-phase microextraction operated in the head-space mode (HS-SPME). An innovative method that is based on the extraction of the oil by dynamic maceration at room temperature from plant inflorescences, which were partially decarboxylated in a closed system at a moderate temperature and partially pre-extracted with ethanol, produced similar yields of bioactive compounds as that obtained by using a microwave-assisted distillation of the essential oil from the plant material, in combination with a maceration extraction of the oil from the residue. Both these new methods provided a higher efficiency over already existing extraction procedures of medical Cannabis oils and they can be applied to obtain a product with a high therapeutic value.