Comparative Metabolomic Profiling of the Metabolic Differences of Δ9-Tetrahydrocannabinol and Cannabidiol

More than one hundred cannabinoids have been found in cannabis. Δ9-Tetrahydrocannabinol (THC) is the recognized addictive constituent in cannabis; however, the mechanisms underlying THC-induced toxicity remain elusive. To better understand cannabis-induced toxicity, the present study compared the metabolic pathways of THC and its isomer cannabidiol (CBD) in human and mouse liver microsomes using the metabolomic approach. Thirty-two metabolites of THC were identified, including nine undescribed metabolites. Of note, two glutathione (GSH) and two cysteine (Cys) adducts were found in THC’s metabolism. Molecular docking revealed that THC conjugates have a higher affinity with GSH and Cys than with the parent compound, THC. Human recombinant cytochrome P450 enzymes, and their corresponding chemical inhibitors, demonstrated that CYP3A4 and CYP1B1 were the primary enzymes responsible for the formation of THC-GSH and THC-Cys, thus enabling conjugation to occur. Collectively, this study systematically compared the metabolism of THC with the metabolism of CBD using the metabolomic approach, which thus highlights the critical role of metabolomics in identifying novel drug metabolites. Moreover, this study also facilitates mechanistic speculation in order to expand the knowledge of drug metabolism and safety.     

Botanically-Derived Δ9-Tetrahydrocannabinol and Cannabidiol,and Their 1:1 Combination,Modulate Toll-like Receptor 3 and 4 Signalling in Immune Cells from People with Multiple Sclerosis

The innate immune response to bacterial and viral molecules involves the coordinated production of cytokines, chemokines, and type I interferons (IFNs), which is orchestrated by toll-like receptors (TLRs). TLRs, and their intracellular signalling intermediates, are closely associated with multiple sclerosis (MS) pathogenesis. Recent data from our laboratory reported that the plant-derived cannabinoids, Δ⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD), regulate viral and bacterial inflammatory signalling pathways controlled by TLR3 and TLR4 in macrophages. The aim of this study was to assess the impact of THC and CBD, when delivered in isolation and in combination (1:1), on TLR3- and TLR4-dependent signalling in peripheral blood mononuclear cells (PBMCs) from people with MS (pwMS; n = 21) and healthy controls (HCs; n = 26). We employed the use of poly(I:C) and lipopolysaccharide (LPS) to induce viral TLR3 and bacterial TLR4 signalling, and PBMCs were pre-exposed to plant-derived highly purified THC (10 μM), CBD (10 μM), or a combination of both phytocannabinoids (1:1 ratio, 10:10 μM), prior to LPS/poly(I:C) exposure. TLR3 stimulation promoted the protein expression of the chemokine CXCL10 and the type I IFN-β in PBMCs from both cohorts. THC and CBD (delivered in 1:1 combination at 10 μM) attenuated TLR3-induced CXCL10 and IFN-β protein expression in PBMCs from pwMS and HCs, and this effect was not seen consistently when THC and CBD were delivered alone. In terms of LPS, TLR4 activation promoted TNF-α expression in PBMCs from both cohorts, and, interestingly, CBD when delivered alone at 10 μM, and in combination with THC (in 1:1 combination at 10 μM), exacerbated TLR4-induced TNF-α protein expression in PBMCs from pwMS and HCs. THC and CBD displayed no evidence of toxicity in primary PBMCs. No significant alteration in the relative expression of TLR3 and TLR4 mRNA, or components of the endocannabinoid system, including the cannabinoid receptor CB₁ (encoded by CNR1 gene) and CB₂ (encoded by CNR2 gene), and endocannabinoid metabolising enzymes, fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MGLL), was determined in PBMCs from pwMS versus HCs. Given their role in inflammation, TLRs are clinical targets, and data herein identify CBD and THC as TLR3 and TLR4 modulating drugs in primary immune cells in vitro. This offers insight on the cellular target(s) of phytocannabinoids in targeting inflammation in the context of MS.     

Ruthenium(II/III)‐Based Compounds with Encouraging Antiproliferative Activity against Non‐small‐Cell Lung Cancer

Hereby we present the synthesis of several ruthenium(II) and ruthenium(III) dithiocarbamato complexes. Proceeding from the Na[trans‐Ru^III(dmso)₂Cl₄] ( 2 ) and cis‐[Ru^II(dmso)₄Cl₂] ( 3 ) precursors, the diamagnetic, mixed‐ligand [Ru^IIL₂(dmso)₂] complexes 4 and 5 , the paramagnetic, neutral [Ru^IIIL₃] monomers 6 and 7 , the antiferromagnetically coupled ionic α‐[Ru^III₂L₅]Cl complexes 8 and 9 as well as the β‐[Ru^III₂L₅]Cl dinuclear species 10 and 11 (L=dimethyl‐ (DMDT) and pyrrolidinedithiocarbamate (PDT)) were obtained. All the compounds were fully characterised by elemental analysis as well as ¹H NMR and FTIR spectroscopy. Moreover, for the first time the crystal structures of the dinuclear β‐[Ru^III₂(dmdt)₅]BF₄ ? CHCl₃ ? CH₃CN and of the novel [Ru^IIL₂(dmso)₂] complexes were also determined and discussed. For both the mono‐ and dinuclear Ru^II and Ru^III complexes the central metal atoms assume a distorted octahedral geometry. Furthermore, in vitro cytotoxicity of the complexes has been evaluated on non‐small‐cell lung cancer (NSCLC) NCI‐H1975 cells. All the mono‐ and dinuclear Ru^III dithiocarbamato compounds (i.e., complexes 6 – 10 ) show interesting cytotoxic activity, up to one order of magnitude higher with respect to cisplatin. Otherwise, no significant antiproliferative effect for either the precursors 2 and 3 or the Ru^II complexes 4 and 5 has been observed.     

Structure–Activity Relationship of the Thiacalix[4]arenes Family with Sulfobetaine Fragments: Self-Assembly and Cytotoxic Effect against Cancer Cell Lines

Regulating the structure of macrocyclic host molecules and supramolecular assemblies is crucial because the structure–activity relationship often plays a role in governing the properties of these systems. Herein, we propose and develop an approach to the synthesis of the family of sulfobetaine functionalized thiacalix[4]arenes with regulation of the self-assembly and cytotoxic effect against cancer cell lines. The dynamic light scattering method showed that the synthesized macrocycles in cone, partial cone and 1,3-alternate conformations form submicron-sized particles with Ag⁺ in water, but the particle size and polydispersity of the systems studied depend on the macrocycle conformation. Based on the results obtained by ¹H and ¹H-¹H NOESY NMR spectroscopy and transmission electron microscopy for the macrocycles and their aggregates with Ag⁺, a coordination scheme for the Ag⁺ and different conformations of p-tert-butylthiacalix[4]arene functionalized with sulfobetaine fragments was proposed. The type of coordination determines the different shapes of the associates. Cytotoxic properties are shown to be controlled by the shape of associates, with the highest activity demonstrated by thiacalix[4]arenes in partial cone conformation. This complex partial cone/Ag⁺ is two times higher than the reference drug imatinib mesylate. High selectivity against cervical carcinoma cell line indicates the prospect of their using as components of new anticancer system.     

Cannabidiol and Its Combinations with Nonsteroidal Anti-Inflammatory Drugs Induce Apoptosis and Inhibit Activation of NF-κB Signaling in Vulvar Squamous Cell Carcinoma

Vulvar squamous cell carcinoma (VSCC) is a rare malignancy with a relatively good prognosis. However, the prognosis remains poor for elderly patients and those with a significant depth of tumor invasion; thus, novel treatment modalities are needed. The aim of this study was to analyze the impact of cannabidiol (CBD) and its combination with NSAIDs, diclofenac (DIC) and ibuprofen (IBU) on VSCC cells. In this regard, the MTT test was applied for cytotoxicity analysis. Moreover, the influence of CBD, DIC and IBU, as well as their combinations, on apoptosis and cell cycle distribution were analyzed by flow cytometry. The mechanisms of action of the analyzed compounds, including their impact on NF-κB signaling, p53 and COX-2 expression were evaluated using Western blot. This study shows that CBD and its combinations with NSAIDs are cytotoxic to A431 cells, but they also reduce, in a dose-dependent manner, the viability of immortalized keratinocyte HaCaT cells, and human umbilical vein cell line, EA.hy926. Moreover, the compounds and their combinations induced apoptosis, diminished the NF-κB signaling activation and reduced COX-2 expression. We conclude that CBD and its combination with DIC or IBU are promising candidates for the adjuvant treatment of high-risk VSCC patients. However, their impact on non-cancerous cells requires careful evaluation.