Protective Effects of Zinc on Cadmium Toxicity in Rodents

Abstract

A study of acute and subacute toxicity of cadmium ions [Cd(II)] was carried out on male Swiss mice and Sprague-Dawley rats with and without previous administration of zinc chloride. The LD50 of Cd(II) as cadmium sulfate (ip) was lower in animals previously given 10 mg/kg of zinc(II) chloride (sc). Factors such as animal weight variations, biochemical parameters, and accumulation patterns of Cd(II) and Zn(II) were taken into consideration when the subacute toxicity was evaluated. Alteration of the activities of glutamic pyruvic transaminase (GPT) and of glutamic oxaloacetic transaminase (GOT) was observed in short-term-exposure (<6 h) cases. These alterations reverted to normal after 1 wk. The activity of alkaline phosphatase (ALP) and the concentrations of cholesterol and triglycerides in serum are also changed, especially so in the groups given CdSO4 alone. In the experimental groups treated with ZnCl2 prior to administration of cadmium, proteinuria was detected 5 wk after the treatment. Also at 5 wk, both Zn-treated and nontreated groups showed an abnormally low liver mass with respect to total body mass. Both Cd and Zn are retained preferentially in the liver but show also in the kidneys. If CdSO4 and ZnCl2 are given simultaneously, especially after 1 wk of treatment, Cd is accumulated in greater amounts in these organs when compared to the groups given only cadmium sulfate.

Deregulation of transition metals homeostasis is a key feature of cadmium toxicity in Salmonella

“…These findings indicate that induction of ZnuABC is required to increase zinc uptake in response to cadmium intoxication. The protective effect of zinc against cadmium toxicity has long been documented in eukaryotic systems, where it was observed that zinc supplementation can lower the deleterious effects of cadmium exposure (Claverie et al 2000;Brzoska et al 2007;Galazyn-Sidorczuk et al 2012), and that a low dietary zinc intake can be associated with a higher risk of cadmium-induced cancer in humans . Our study on Salmonella and other studies on prokaryotes (Maynaud et al 2013;Zeng et al 2012) support the idea that a proper zinc intake is necessary to face cadmium-induced stress, because cadmium triggers signals of zinc shortage.…”

Effects of Zinc Coadministration on Lead Toxicities in Rats

“…The blood Zn recoveries (M ± SD) were 98 ± 8% (RSD = 2.35%) and 99 ± 8% (RSD = 1.89%) when the concentrations of standard Zn solution were 50 µg/l and 100 µg/l, respectively. Detection limit of Zn was 1.8 µg/l 15,16) .…”

Protective Effects of Zinc on Testes of Cadmium-Treated Rats

“…Histological and biochemical studies have shown that acute and chronic exposure to Cd adversely affects a number of organs, including kidney, liver, testis and lung (Klaassen 1999;Yiin et al 1999;Claveria et al 2000;Patrick 2003). Trace elements appear to protect toxic effect of heavy metals on the tissue histology.…”

“…Zn is an essential mineral for spermatogenesis and a hepatocellular MT inducer, and zinc co-treatment protects tissues against free radicals and oxidative stress (Afonne 2002). The beneficial role of zinc against cadmium-induced testicular damage has also been reported, although its antioxidant mechanism is unclear (Batra et al 1998;Claveria et al 2000;Rotsan et al 2002;Xu et al 2005). Nevertheless, several mechanisms have been proposed for zinc.…”