Toxicological effects of caffeine on the antioxidant defense system and some biochemical responses in earthworm, Allolobophora caliginosa

Abstract

Allolobophora caliginosa, an earthworm, was exposed to caffeine (CAF) via artificial soil to evaluate the effects on antioxidant enzymes in animals treated to 0, 10, 20, 40, and 80 mg CAF/kg soil after 7, 14, 28, and 56 d of exposure. There is evidence that antioxidant enzymes protect cells from free radical damage. A high CAF concentration generated changes in the activities of superoxide dismutase (SOD), catalase (CAT), and guaiacol peroxide (POD), but had slight effects on malondialdehyde (MDA) levels after 56 d of exposure. Earthworms¢ MDA levels elevated somewhat after 7, 14, and 28 d. Earthworms treated with CAF were unable to induce the cytotoxic action over a very long period of time (56 d), as three enzymes [polyphenol oxidase (PPO), acetyl cholinesterase (AChE), and cellulose] were significantly inhibited. These data support the notion that oxidative stress plays a role in the response of earthworms to CAF poisoning.