Chromosomal and biochemical studies on the effect of kat extract on laboratory rats

Abstract

Kat is being used extensively in many countries as a central nervous system stimulant. The effect of three doses of crude kat extract on chromosomal division and abnormalities in bone marrow, as well as on DNA, RNA, and total protein content in brain and liver was studied in laboratory rats in order to test the possible mutagenicity of the drug. Kat was given as a single subcutaneous injection at 0.05 (usage dose), 0.52 (intermediate dose), and 1.00 (sublethal dose) g/kg body weight. Animals were sacrificed at 6, 24, and 48 hr after treatment. Also, some animals were exposed subacutely for 5 consecutive days with sacrifice occurring 6 hr after the last injection. The mitotic index was reduced by all treatments, with the greatest effect occurring in the subacute treatment. Chromosomal abnormalities were induced by kat at all three doses, administered acutely or subacutely. The significant chromosomal aberrations were in the form of gaps, breaks, centromeric attenuations, and centric fusions. The concentration of DNA, RNA, and total protein in liver and brain decreased at all doses, with the greatest decrease occurring after subacute treatment. These findings suggest that kat has a profound effect on cell proliferation, on chromosomal abnormalities, and on DNA, RNA, and total protein synthesis.

Khat (Catha edulis) lowers plasma luteinizing hormone (LH) and testosterone secretion, but increases cortisol levels in male rabbits

“…Perhaps of particular importance is the mitodepressive activity of khat and cathinone (Al-Meshal, 1987). Khat extract and cathinone have been shown to depress cell proliferation and inhibit RNA, DNA and protein synthesis in dividing cells, which may be responsible for reduced spermatogenesis (Hammouda, 1971;De Hondt et al, 1984;Al-Meshal et al, 1989).…”

Molecular Modes of Action of Defensive Secondary Metabolites

“…Reduction in fertility and dose-dependent postimplantation loss but no dominant lethality was observed (Qureshi et al, 1988). However, the alkaloid produced chromosomal aberrations in rats (De Hondt et al, 1984) and in somatic cells of mice (Tariq et al, 1987). The mechanism of action is unknown at present.…”

Protective role of interferon against cytotoxcicity induced by rabies virus in mice

“…Where there was a significant increase in structural chromosomal aberrations, it was mainly due to significant increase in centromeric fusion, breaks, rings and centromeric attenuation (except after low concentration). Centromeric attenuation may lead to a concomitant increase in endomitosis and polyploidy (de Hondt et al, 1984).…”