Effects of Khat on the Brain in Male and Female Mice

Background: Substance use and related disorders are becoming public health concerns globally. Catha edulis, commonly called khat, is a psychostimulant plant chewed by East African people and its anxiety-like effect has not been investigated experimentally in animal models. Although the results are inconsistent, the peripheral lipid peroxidation effect of khat is investigated. However, its brain lipid peroxidation effect represented by an increase in the malondialdehyde level has not been investigated. The increase in the MDA level could be associated with a khat-induced increase in the generation of free radicals and oxidation of lipids. These are the main problems driving this study. The aim of this study is, therefore, to investigate the anxiety-like and prefrontal cortex (PFC) lipid peroxidation effects of khat in animal models of both sexes.

Methods: A total of 40 white albino mice in 4 groups (n= 10 / group, 5 males, and 5 females/group) aged between 7 and 8 weeks were used. They were administered with khat extract (Ke) 100 mg/kg, 200 mg/kg, 300 mg/kg b.w, and 2% tween 80 in distilled water (T80W-v/v) for thirteen weeks. The anxiety-like behaviors and PFC malondialdehyde (MDA) level were measured using elevated plus maze and spectrophotometry, respectively. One-way ANOVA, Pearson’s correlation, and independent t-tests were used. P-value 0.05 was considered statistically significant.

Results: Ke 100 mg/kg (p < 0.05), Ke 200 mg/kg (p < 0.01), and Ke 300 mg/kg (p < 0.01) reduced open arm entry. Ke 100 mg/kg (p < 0.01), Ke 200 mg/kg (p < 0.01), and 300 mg/kg (p < 0. 01) also reduced open arm duration. Ke 200 mg/kg (p<0.01) and Ke 300 mg/kg (p<0.001) increased the right PFC MDA level while the MDA in the left PFC was increased by the higher dose of the extract (300 mg/kg).

Conclusions: Catha edulis showed anxiety-like behaviors in the elevated plus maze paradigm and increased prefrontal cortex malondialdehyde level. Further studies are needed on the prefrontal cortex neurochemicals effects of this extract.