Screening System of Cannabis sativa Extracts Based on Their Mitochondrial Safety Profile Using Cytochrome c Oxidase Activity as a Biomarker

The development of Cannabis sativa strains with high cannabidiol (CBD) and low tetrahydrocannabinol (THC) content is a growing field of research, both for medical and recreational use. However, the mechanisms behind clinical actions of cannabinoids are still under investigation, although there is growing evidence that mitochondria play an important role in many of them. Numerous studies have described that cannabinoids modulate mitochondrial activity both through activation of mitochondrial cannabinoid receptors and through direct action on other proteins such as mitochondrial complexes involved in cellular respiration. Thus, the aim of this study was to determine the actions of a panel of extracts, isolated from high-CBD varieties of Cannabis sativa, on the activity of the mitochondrial electron transport chain complex IV, cytochrome c oxidase (CCO), in order to select those with a safer profile. After demonstrating that Cannabis sativa strains could be identified by cannabinoids content, concentration-response curves were performed with a collection of extracts from strains with high-CBD and low-THC content using bovine CCO. The CCO rate was clearly modified by specific extracts of Cannabis sativa plants compared to others. Half maximal inhibitory concentrations (IC50) of extracts and the inhibitory effects evoked at 1 × 10-4 g/mL displayed a significant correlation with the THC. Therefore, the screening of extracts based on CCO activity provides a powerful and rapid methodology to identify those plants with higher mitochondrial toxicity or even mito-protective actions.

Characterization of the Antitumor Potential of Extracts of Cannabis sativa Strains with High CBD Content in Human Neuroblastoma.

Cannabis has been used for decades as a palliative therapy in the treatment of cancer. This is because of its beneficial effects on the pain and nausea that patients can experience as a result of chemo/radiotherapy. Tetrahydrocannabinol and cannabidiol are the main compounds present in Cannabis sativa, and both exert their actions through a receptor-mediated mechanism and through a non-receptor-mediated mechanism, which modulates the formation of reactive oxygen species. These oxidative stress conditions might trigger lipidic changes, which would compromise cell membrane stability and viability. In this sense, numerous pieces of evidence describe a potential antitumor effect of cannabinoid compounds in different types of cancer, although controversial results limit their implementation. In order to further investigate the possible mechanism involved in the antitumoral effects of cannabinoids, three extracts isolated from Cannabis sativa strains with high cannabidiol content were analyzed. Cell mortality, cytochrome c oxidase activity and the lipid composition of SH-SY5Y cells were determined in the absence and presence of specific cannabinoid ligands, with and without antioxidant pre-treatment. The cell mortality induced by the extracts in this study appeared to be related to the inhibition of the cytochrome c oxidase activity and to the THC concentration. This effect on cell viability was similar to that observed with the cannabinoid agonist WIN55,212-2. The effect was partially blocked by the selective CB1 antagonist AM281, and the antioxidant α-tocopherol. Moreover, certain membrane lipids were affected by the extracts, which demonstrated the importance of oxidative stress in the potential antitumoral effects of cannabinoids.

Linear and Cyclic Depsipeptidomimetics with ß-Lactam Cores: A Class of New αv ß3 Integrin Receptor Inhibitors.

The αv ß3 integrin receptor plays an important role in tumor metastasis and tumor-induced angiogenesis. The inhibition of this receptor with diverse ligands, antibodies, or cyclic peptides is a promising research field for the treatment of a variety of tumors. The replacement of Phe-(Me)Val dipeptide by a ß-lactam ring in Cilengitide has led to new products that show higher inhibitory activity than the parent cyclopeptide. In particular, substitution of a peptide bond ß-lactam-NH-Asp linkage by a ß-lactam-O-Asp ester linkage increases the activity of the new cyclodepsipeptide. In the same way it has been found that open-chain compounds of the form Asp-ß-lactam-Arg can interact with the receptor and inhibit its activity moderately. The integrin inhibitory activity of the synthesized compounds has been established by using the CGH array, a method that appears to be a more reliable trial than the classical adhesion test.

Study of Tissue-Specific Reactive Oxygen Species Formation by Cell Membrane Microarrays for the Characterization of Bioactive Compounds.

The production of reactive oxygen species (ROS) increases considerably in situations of cellular stress, inducing lipid peroxidation and multiple alterations in proteins and nucleic acids. However, sensitivity to oxidative damage varies between organs and tissues depending on the triggering process. Certain drugs used in the treatment of diverse diseases such as malaria have side effects similar to those produced by oxidative damage, although no specific study has been conducted. For this purpose, cell membrane microarrays were developed and the superoxide production evoked by the mitochondrial activity was assayed in the presence of specific inhibitors: rotenone, antimycin A and azide. Once the protocol was set up on cell membrane isolated from rat brain areas, the effect of six antimalarial drugs (atovaquone, quinidine, doxycycline, mefloquine, artemisinin, and tafenoquine) and two essential oils (Rosmarinus officinalis and Origanum majoricum) were evaluated in multiple human samples. The basal activity was different depending on the type of tissue, the liver, jejunum and adrenal gland being the ones with the highest amount of superoxide. The antimalarial drugs studied showed specific behavior according to the type of human tissue analyzed, with atovaquone and quinidine producing the highest percentage of superoxide formation, and doxycycline the lowest. In conclusion, the analysis of superoxide production evaluated in cell membranes of a collection of human tissues allowed for the characterization of the safety profile of these antimalarial drugs against toxicity mediated by oxidative stress.

[Recommendations for respiratory support in the newborn (IV). High frequency ventilation, ex-utero intrapartum treatment (EXIT), extracorporeal membrane oxygenation (ECMO)]. / Recomendaciones para la asistencia respiratoria en el recién nacido (IV). Ventilación de alta frecuencia, ex-utero intrapartum treatment (EXIT), oxigenador de membrana extracorpórea (ECMO).

The recommendations included in this document will be part a series of updated reviews of the literature on respiratory support in the newborn infant. These recommendations are structured into 12 modules, and in this work module 8 is presented. Each module is the result of a consensus process amongst all members of the Surfactant and Respiratory Group of the Spanish Society of Neonatology. They represent a summary of the published papers on each specific topic, as well as the clinical experience of each one of the members of the group.

Sequence variation and mRNA expression of the TWIST1 gene in cats with mammary hyperplasia and neoplasia.

In humans, a germline mutation (c.309C>G) in the TWIST1 oncogene may predispose to breast cancer and its expression has been associated with tumour progression and metastasis. In this study, the feline TWIST1 gene was screened for sequence variations in 37 neoplastic and eight hyperplastic mammary gland lesions from cats. In addition, mRNA levels were examined in 15 mammary tumours and three cases of mammary hyperplasia by quantitative real-time reverse-transcriptase PCR. Feline mammary carcinomas had significantly lower levels of expression of TWIST1 mRNA than benign mammary tumours. No variations were identified in the TWIST1 coding region in feline mammary tumours and the mutation described in humans was not detected. However, two germline variants in the TWIST1 gene intron were identified in four and three carcinomas, respectively: GQ167299:g.535delG and GQ167299:g.460C>T. There was no association between these sequence alterations and TWIST1 mRNA levels.

Catalytic enantioselective aza-Henry reaction with broad substrate scope.

In situ generated azomethines from readily available precursors react with nitromethane in the presence of 120 mol % of CsOH.H2O and 12 mol % of quinine- and cinchonidine-derived quaternary ammonium chlorides to provide the corresponding aza-Henry adducts in good yields and very high selectivities. It represents the first general enantioselective aza-Henry method for azomethines derived from enolizable aldehydes, giving rise to enantiomeric excesses above 94%. In addition, the reactions with nitroethane afforded high diastereo- and enantioselectivities (syn:anti up to 95:5; up to 98% ee for syn).