Effects of Chlorella vulgaris on the Liver Toxicity in Cadmium Administered Rats

To investigate the biochemical effect of Chlorella vulgaris on liver toxicity induced by 50 ppm cadmium (Cd), male Sprague‐Dawley rats(aged 5 weeks old, weighed 90–110g) were used. Forty rats (n=10/group) were randomly divided into one control and three Cd groups: chlorella free diet group(Cd‐0C) or 5% chlorella diet group(Cd‐5C) or 10% chlorella diet group(Cd‐10C). The rats had freely access to water and diet for 8 weeks. Body weight gain and relative liver weight had lower in Cd‐0C(43.8¡¾12.6, 3.1¡¾0.5g/100g b.w.) than in Cd‐5C(77.1¡¾21.7, 2.8¡¾0.6/100g b.w.) and Cd‐10C(77.1¡¾33.6, 2.6¡¾0.5g/100g b.w.) (p<0.05). Rats in Cd‐0C(54.5¡¾0.2mg/g, 9.4¡¾1.0mg/g, 0.3¡¾0.0mg/g) had higher hepatic Cd concentration, T‐MTs, and Cd‐MTs concentrations compared to those in Cd‐5C(43.9¡¾7.6mg/g, 6.8¡¾3.2mg/g, 0.2¡¾0.0mg/g), or Cd‐10C(47.4¡¾2.4mg/g, 6.4¡¾3.8mg/g, 0.2¡¾0.0mg/g)(p<0.05). The MT I/II mRNA was expressed by RT‐PCR in the liver of all experimental rats. The expression was more strongly increased in Cd‐5C or Cd‐10C compared to control and Cd‐0C. Thus, this study suggests that chlorella vulguris would have a protective effect on Cd‐induced liver damage by reducing Cd concentrations and stimulating Cd‐MT binding in liver