In Vivo Evaluation of Full Extract on Zebrafish Larvae Development, Locomotion Behavior and Gene Expression.

Historically, humans have been using for both recreational and medical purposes. Nowadays, cannabis-based products have gained scientific interest due to their beneficial effects on several syndromes and illnesses. The biological activity of cannabinoids is essentially due to the interaction with the endocannabinoid system, and zebrafish () is a very well-known and powerful in vivo model for studying such specific interactions. The aim of the study was to investigate the effects of different doses of a whole extract [dissolved in dimethyl sulfoxide (DMSO)] on zebrafish eggs' hatchability, embryo post-hatching survival, larvae locomotion behavior and mRNA gene expression. The results showed the absence of toxicity, and no significant differences were observed between treatments for both embryo hatching and survival rate. In addition, larvae exposed to the cannabis extract at the highest dose [containing 1.73 nM and 22.3 nM of ∆-tetrahydrocannabinol (THC) and cannabidiol (CBD), respectively] showed an increased locomotion compared to the control and DMSO treated groups. Moreover, qRT-PCR analysis showed that the highest dosage of cannabis induced an over-expression of and cannabinoid receptors. In conclusion, the exposition of zebrafish larvae to the whole extract of showed no negative effects on embryo development and survival and enhanced the larvae's locomotor performances. These findings may open up possible applications in human pharmacology as well as in other animal sectors.