Cannabis-like activity of Zornia latifolia Sm. detected in vitro on rat cortical neurons: major role of the flavone syzalterin

• Autor(a) principal: Alloisio, Susanna
• Data de Publicação: 2020
• Outros Autores: Clericuzio, Marco, Nobile, Mario, Salis, Annalisa, Damonte, Gianluca, Canali, Claudia, Fortuna-Perez, Ana Paula [UNESP], Cornara, Laura, Burlando, Bruno
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1080/01480545.2020.1788057; http://hdl.handle.net/11449/199084
• topic: Flavonoids; hashish; multielectrode array; psychoactive metabolites; smart drugs

Zornia latifolia is a plant suspected to possess psychoactive properties and marketed as a marijuana substitute under the name ‘maconha brava’. In this study, the effects of fractions obtained from a 2-propanol extract of aerial portions of the plant were determined by multielectrode array (MEA) analyses on cultured networks of rat cortical neurons. Lipophilic (ZL_lipo, mainly containing flavonoid aglycones), and hydrophilic (ZL_hydro, mainly containing flavonoid glycosides) fractions were initially obtained from the raw extract. ZL_lipo significantly inhibited mean firing rate (MFR) and mean bursting rate (MBR) of MEA recordings, while ZL_hydro induced no inhibition. Column chromatography separation of ZL_lipo yielded five fractions (ZL1-ZL5), among which ZL1 induced the strongest MFR and MBR inhibition. NMR and HPLC-MS analyses of ZL1 revealed the prevalence of the common flavonoids genistein (1) and apigenin (2) (in about a 1:1 ratio), and the presence of the rare flavone syzalterin (6,8-dimethylapigenin) (3) as a minor compound. Exposures of MEA to apigenin and genistein standards did not induce the MFR and MBR inhibition observed with ZL1, whereas exposure to syzalterin standard or to a 1:9 mixture syzalterin-genistein induced effects similar to ZL1. These inhibitory effects were comparable to that observed with high-THC hashish, possibly accounting for the plant psychoactive properties. Data indicate that Z. latifolia, currently marketed as a free herbal product, should be subjected to measures of control. In addition, syzalterin showed distinctive pharmacological properties, opening the way to its possible exploitation as a neuroactive drug.