Lead induces apoptosis in mouse TM3 Leydig cells through the Fas/FasL death receptor pathway

Area of Science:

• Toxicology
• Cell Biology
• Reproductive Biology

Background:

• Lead (Pb) is a toxic heavy metal with known adverse effects on reproductive health.
• Leydig cells are crucial for testosterone production in the testes.
• Understanding the molecular mechanisms of lead toxicity in Leydig cells is essential for addressing male reproductive dysfunction.

Purpose of the Study:

• To investigate the toxic effects of lead (Pb) on mouse Leydig TM3 cells.
• To elucidate the molecular mechanisms underlying Pb-induced Leydig cell apoptosis.
• To explore the role of the Fas/FasL signaling pathway in Pb toxicity.

Main Methods:

• In vitro culture of mouse Leydig TM3 cells exposed to varying Pb concentrations.
• Assessment of cell proliferation using MTT assay.
• Analysis of apoptosis via Annexin V-FITC/PI staining and flow cytometry.
• Determination of Fas, Fas-Ligand (Fas-L), and caspase-8 expression by Western blot.
• Evaluation of caspase-8 inhibitor (Z-IETD-FMK) effects on Pb-induced apoptosis.

Main Results:

• Pb exposure significantly reduced Leydig cell viability (P<0.05).
• Pb treatment markedly increased Leydig cell apoptosis (P<0.01).
• Expression levels of Fas, Fas-L, and caspase-8 were significantly upregulated in Pb-exposed cells (P<0.05 or P<0.01).
• The caspase-8 inhibitor Z-IETD-FMK effectively suppressed Pb-induced apoptosis.

Conclusions:

• Lead toxicity induces apoptosis in mouse Leydig TM3 cells.
• The Fas/FasL death receptor signaling pathway is implicated in Pb-induced Leydig cell apoptosis.
• Targeting caspase-8 may offer a therapeutic strategy against lead-induced reproductive toxicity.