Hepatic and reproductive toxicity of lead in female rats and attenuation by flaxseed lignans

الملخص EN

Background : Earthworms may serve as bio indicators of soil contaminated with heavy metals.

The Allolobophra caliginosa samples were collected from three different roadsides in addition to a control site.

Results obtained showed that the concentration of the heavy metals in the worms tissue were found to follow the descending orders; Fe > Zn > Cu > Pb > Cd > Cr > Ni, in the three different roadsides compared to the control one.

The lead concentration was found to be higher than Cd , Cr and Ni, the main toxic metals.

The objective of this study was to investigate the propensity of lead to induce hepatotoxicity and changes in serum levels of progesterone and estradiol-17B and their metabolizing enzymes in female rats following a short-term (21 days) oral exposure and its possible attenuation by flaxseed lignans.

Rats were assigned to 1 of 3 treatment groups; the first was the control group, the second was lead acetate- treated group and the third was lead acetate + flaxseed lignans- treated group.

Enzyme activities of aminotransferases (ALT and AST), alkaline phosphatase (AlP), total proteins and albumin were significantly (p<0.05) decreased in liver.

Meanwhile, the activities of AST and ALT in serum were significantly (p<0.05) increased in lead acetate-treated group.

The activities of these enzymes were normalized in the combination group.

On the other hand, the serum levels of progesterone and estradiol- 17B were significantly decreased in the lead acetate-treated rats compared to controls.

The treatment with flaxseed lignans plus lead acetate alleviated the decrease in the levels of the two hormones.

The specific activities of both 5B-reductase and 17B-hydroxysteroid dehydrogenase were significantly (p<0.05) increased in liver and uterine extracts of lead acetate treated rats compared to controls.

Flaxseed lignans alleviated the increased enzyme activities in the combination group.

The present study revealed that the presence of flaxseed lignans could diminish the adverse effects of lead acetate as shown in the histological analysis of rat livers.