Effect of Daily Chewing Soft Buds and Leaves of Catha edulis (Khat) on the Antioxidant Defense System and Oxidative Stress Markers in Blood

Abstract

Catha edulis (Khat) is one of the major economic, social and health problems in Yemen. This paper aimed to study the effect of Khat on the oxidative status of Khat chewers by measuring the levels of enzymatic and non-enzymatic antioxidant as well as lipid peroxidation. The results exhibited significant reduction in erythrocytes superoxide dismutase (SOD, EC: 1.15.1.1), and catalase (CAT, EC: 1.11.1.6) in Khat chewers, in addition to elevation of serum glutathione-S-transferase (GST, EC: 2.5.1.18). Furthermore, non-enzymatic antioxidants glutathione (GSH) and vitamin C were significantly reduced ( p < 0.001; p < 0.015), whereas malondialdehyde (MDA) was significantly elevated ( p < 0.001). The depletion of GSH and vitamin C along with MDA elevation in Khat chewers compared with control reflects the obvious oxidative status, a result of enormous reactive oxygen species (ROS) formation, leading to membrane damage. ROS possibly induced by active components of Khat or by pesticides added to the Khat tree. In addition, the reduction of SOD and CAT is indicative to cellular proteins damage which occurred by ROS. As well, the elevation of GST may due to a leakage of cellular GST to blood stream; this implies that GST active site was not affected. This study concludes that daily chewing Khat for long period certainly induce ROS production, leading to oxidative toxicity. Both enzymatic and non-enzymatic antioxidants are involved in the protection against this toxicity. People who habitually chew Khat for long term will be susceptible to the oxidative toxicity; therefore, they recommended giving up of Khat chewing.

Exploring the efficacy of catha edulis extract-loaded nanofibrous scaffolds seeded with bone marrow-derived stem cells for diabetic wound healing: A preclinical investigation

“…The extract's phenolic compounds donate electrons to free radicals, stabilizing them and preventing them from interacting with other molecules. 31,32 Hemocompatibility assay…”

Impact of Khat (Catha edulis) Chewing on Inflammatory Markers and Advanced Glycation End Products among Yemeni Women

“…Nearly 90% of adult males and more than 50% of females chewed on khat for 3 to 4 h. daily [2]. The daily chewing Khat lead to produce Reacctive oxygen species (ROS) and oxidative toxicity [3], which is always associated with high inflammation.…”