Effect of a controlled food-chain mediated exposure to cadmium and arsenic on oxidative enzymes in the tissues of rats

Abstract

ObjectiveThe present study aims to investigate the effect of cadmium and arsenic through a controlled food chain on the activities of some oxidative enzymes (Sulphite oxidase SO, Aldehyde oxidase AO, Monoamine oxidase MO and Xanthine oxidase, XO) in the liver, kidney, testes, heart and brain of rats.Materials and methodsFish (the first trophic level) were exposed to both metals (singly and in mixture) using cadmium chloride (CdCl2) as the source of cadmium and arsenic trioxide (AS2O3) as the source of arsenic at a concentration of 0.4 mg of metals/100 ml of water for 1 month and then sacrificed. The contaminated fish were then used as a source of protein in compounding the experimental diet to which the rats (the second trophic level) were exposed to for a period of 1 and 3 months. The Cd- and As-load in the feed and tissues of rats as well as the activities of the oxidative enzymes were subsequently analyzed in the various tissues after both period of exposure.ResultsMetal analysis on the tissues of rats showed that the metals accumulated more in the liver than in other organs after the 1 month exposure but accumulated more in the kidney after the 3 months exposure. The activities of the oxidative enzymes in the liver were significantly (P < 0.05) decreased in all test groups after the 1 and 3 months exposure. However, after the 1 month exposure, the kidney, testes and heart showed an initial increase in the activities of these enzymes which were decreased after the 3 months exposure. In the brain, the activities of these enzymes were increased in both duration of study.ConclusionFrom the results obtained in the current study, it could be concluded that exposure to cadmium and arsenic through the food chain leads to accumulation of these metals in the tissues of experimental rats leading to the inhibition of oxidative enzymes, thus affecting several normal metabolic processes.

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“…The results of the present study revealed that the animals exposed to Cd through intraperitoneal injections showed loss in the body weight when compared with control rats ( Table 1). This supports the observations reported 28,29 both As and Cd decreased body weight gain and food utilization and that these effects were more pronounced for the mixture. Available reports 30,31,32 also indicate that long term exposure to arsenic and cadmium could lead to significant reduction in body weights.…”

“…It was shown that reduction of body weight can be used as an important indicator for the deterioration of rat general health status. Cd and As inhibitory effect on digestive and absorption enzymes 36, 37 may also account for the decreased in weight of rats as observed 28 . In addition to above findings, in our results we have also find that the administration of α-tocopherol along with Cd shows its reversal effect on the above mentioned brain enzymes and body weights respectively.…”

Baicalein ameliorates cadmium-induced hepatic and renal oxidative damage in rats

“…Cadmium possesses cytotoxic, carcinogenic, and mutagenic properties (Du et al, 2015). It causes hepatotoxicity and nephrotoxicity by acute administration (Ezedom and Asagba, 2016). Kidneys are accepted to be the most target organ of Cd toxicity.…”

Protective Effects of Baicalein against Cadmium-Induced Oxidative Stress in Rat Testes

“…The results in testes differed from those in the liver and kidneys, possibly because the testes have a specific blood testicular barrier; in addition, cadmium cannot easily enter the testes and the organizational structure of different cells may have led to different reactions caused by cadmium. Ezedom and Asagba (2016) reported that the activities of oxidative enzymes increased after rats were exposed to cadmium for one month (P<0.05). This finding may be because the level of cadmium was still at a low accumulated state after the 1 month exposure.…”