Curcumin attenuates oxidative stress-induced altered histoarchitecture of testes in experimentally exposed rats to metal mixture (lead, arsenic, cadmium, mercury, iron, and copper) for 28 days

Abstract

This study was undertaken to assess the toxicity of mixture of six metals including lead (Pb), arsenic (As), cadmium (Cd), mercury (Hg), iron (Fe), and copper (Cu) at environmentally realistic concentrations and to determine whether curcumin was able to prevent testicular injury in rats. Forty-two rats were divided into seven groups, six animals/group: control (water), vehicle control (groundnut oil), curcumin (100 mg/kg body wt.), 10x mixture, 100x mixture, 10x plus curcumin, and 100x plus curcumin. At the end of exposure period of 28 days, rats were sacrificed and testes were collected for the analysis of oxidative stress markers, testicular enzymes, and histopathology. At 10x and 100x dose, % weight gain was significantly reduced compared to control, accompanied by decreased absolute testicular weight in 100x mixture group; however, relative weight among groups did not show any significant difference. Exposure of 10x and 100x mixture elevated the levels of lipid peroxidation products; whereas, catalase activity was significantly lowered. Glutathione content and superoxide dismutase activity were almost comparable among groups. Significant decrease in 17-β-hydroxysteroid hydrogenase and acid phosphatase, increase in γ-glutamyl transferase activity at 100x exposure level was observed. Lactate dehydrogenase and sorbitol dehydrogenase activity was comparable amongst all groups. Histopathological examination revealed degenerative changes in seminiferous tubules and spermatogonial cells. Co-administration of curcumin with metallic mixture effectively countered 10x and 100x metal mixtures-induced oxidative stress and improved antioxidant status of the tissue and restored activities of testicular enzymes. In conclusion, evidence indicates that major action of metals in testicular degeneration may be oxidative stress.