The Toxic Effects of Lead on Testicular Macrophage Immunomodualation and Sperm Cell Parameters in Mice

Aims: In the present study the toxic effects of lead was investigated experimentally on the testicular macrophages and sperm cells isolated from testes of adult male mice to ascertain the extent of immunomodulation and reproductive dysfunctions (in-vivo).

Study Design: Experimental study.

Place and Duration of Study: Department of Biotechnology, Assam University, Silchar, Assam, India, between March 2013 and August 2014.

Methodology: Dose response study was carried out with an increasing concentration of lead acetate. Percent mortality was determined for these doses and plotted graphically against the respective doses. From the graphs, LD50 value was determined. To validate immunomodulation of testicular macrophages and reproductive dysfunction due to lead intoxication, mice were divided into two groups. One group is treated with lead acetate (10 mg/kg body weight) and the other group with isotonic saline solution for 15 days. The isolated testicular macrophages were used to study the phagocytic property, alteration of enzyme release, cytokine release assay and the sperm cell were used for studying the sperm parameters in both control and treated group.

Results: From the study significant decrease in phagocytic index (25516.61±1352.69 to 5154.67±437.37), myeloperoxidase release (77.3±10.7μM to 23.6±4.9μM), nitric oxide release (9.2±1.13 to 4.7±1.69) and a concomitant rise in the pro-inflammatory cytokine TNF-α were observed. These leads to an increased oxidative stress and inflammatory damage in the testes and subsequently less sperm count (78±1.155 to 24.33±1.764), sperm motility and abnormal sperm morphology was documented.

Conclusion: Thus it could be concluded that the toxic potential of lead diminished the functional capacities of testicular macrophages, led to immunomodulation and inflammatory damage in testes and thus impede the sperm function parameters, which bear particular significance in heavy metal induced immune infertility in male.