Molecular Docking and GC/MS-Based Approach for Identification of Anxiolytic Alkaloids from Griffinia (Amaryllidaceae) Species in a Zebrafish Model.

Griffinia gardneriana Ravenna, Griffinia liboniana Morren and Griffinia nocturna Ravenna (Amarillydaceae) are bulbous plants found in tropical regions of Brazil. Our work aimed to determine the alkaloid profiles of Griffinia spp. and evaluate their anxiolytic potential through in vivo and in silico assays. The plants grown in greenhouses were dried and their ground bulbs were subjected to liquid-liquid partitions, resulting in alkaloid fractions that were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). Anxiolytic activity was evaluated in zebrafish (Danio rerio) through intraperitoneal injection at doses of 40, 100 and 200 mg/kg in light-dark box test. GC-MS analyses revealed 23 alkaloids belonging to different skeleton types: lycorine, homolychorine, galanthamine, crinine, haemanthamine, montanine and narcisclasine. The chemical profiles were relatively similar, presenting 8 alkaloids common to the three species. The major component for G. gardneriana and G. liboniana was lycorine, while G. nocturna consisted mainly of anhydrolycorine. All three alkaloid fractions demonstrated anxiolytic effect. Furthermore, pre-treatment with diazepam and pizotifen drugs was able to reverse the anxiolytic action, indicating involving the GABAergic and serotonergic receptors. Molecular docking showed that the compounds vittatine, lycorine and 11,12-dehydro-2-methoxyassoanine had high affinity with both receptors, suggesting them to be responsible for the anxiolytic effect.

Essential Oils from the Genus Piper Promote Antinociception by Modulating TRP Channels and Anti-Inflammatory Effects in Adult Zebrafish.

The Piper genus, known for its pharmacological potential, comprises 2,263 species primarily found in tropical regions. Despite recent advancements in pain therapies, the demand for more effective and well-tolerated analgesics and anti-inflammatories, particularly for chronic pain, remains. This study assessed the effects of essential oils from Piper caldense, Piper mosenii, and Piper mikanianum on nociceptive behavior induced by formalin and capsaicin, as well as their anti-inflammatory impact induced by carrageenan, using adult zebrafish models. Results indicated non-toxic essential oils with antinociceptive properties in both neurogenic and inflammatory phases of formalin-induced nociception through interaction with the TRPA1 receptor. Additionally, P. mosenii essential oil also blocked the nociceptive effect of capsaicin, a TRPV1 receptor agonist. Furthermore, essential oils from P. caldense and P. mikanianum exhibited significant anti-inflammatory effects by reducing carrageenan-induced abdominal edema. These findings highlight the pharmacological potential of Piper's essential oils as antinociceptive and anti-inflammatory agents.