Anti-depressant effects of ethanol extract from Cannabis sativa (hemp) seed in chlorpromazine-induced Drosophila melanogaster depression model

Abstract

Context

Depression is a severe mental illness caused by a deficiency of dopamine and serotonin. Cannabis sativa L. (Cannabaceae) has long been used to treat pain, nausea, and depression.

Objective

This study investigates the anti-depressant effects of C. sativa (hemp) seed ethanol extract (HE) in chlorpromazine (CPZ)-induced Drosophila melanogaster depression model.

Materials and methods

The normal group was untreated, and the control group was treated with CPZ (0.1% of media) for 7 days. The experimental groups were treated with a single HE treatment (0.5, 1.0, and 1.5% of media) and a mixture of 0.1% CPZ and HE for 7 days. The locomotor activity, behavioural patterns, depression-related gene expression, and neurotransmitters level of flies were investigated.

Results

The behavioural patterns of individual flies were significantly reduced with 0.1% CPZ treatment. In contrast, combination treatment of 1.5% HE and 0.1% CPZ significantly increased subjective daytime activity (p < 0.001) and behavioural factors (p < 0.001). These results correlate with increased transcript levels of dopamine (p < 0.001) and serotonin (p < 0.05) receptors and concentration of dopamine (p < 0.05), levodopa (p < 0.001), 5-HTP (p < 0.05), and serotonin (p < 0.001) compared to those in the control group.

Discussion and conclusions

Collectively, HE administration alleviates depression-like symptoms by modulating the circadian rhythm-related behaviours, transcript levels of neurotransmitter receptors, and neurotransmitter levels in the CPZ-induced Drosophila model. However, additional research is needed to investigate the role of HE administration in behavioural patterns, reduction of the neurotransmitter, and signalling pathways of depression in a vertebrate model system.

Keywords:

• Behavioural pattern
• cannabinoid
• neurotransmitter

Disclosure statement

All authors declare that they have no conflicts of interest.

Additional information

Funding

This research was supported by National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. NRF-2019R1A2C1007019).