Seminal cadmium affects human sperm motility through stable binding to the cell membrane

Area of Science:

• Environmental Health
• Reproductive Toxicology
• Human Fertility

Background:

• Global fertility rates are declining, with environmental pollutants implicated as major contributing factors.
• Cadmium (Cd), a heavy metal, is known for reproductive toxicity, but its direct accumulation in human sperm remains under-researched.

Purpose of the Study:

• To investigate the direct impact of Cadmium (Cd) exposure on human sperm function.
• To analyze the cellular accumulation and distribution of Cadmium (Cd) within human sperm cells.

Main Methods:

• Comparison of semen samples from men in high vs. low environmental Cadmium (Cd) exposure areas.
• Quantification of Cadmium (Cd) in semen and sperm cells using inductively coupled plasma (ICP) spectroscopy.
• Assessment of Cadmium (Cd) distribution in sperm using scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS); in vitro exposure experiments were also conducted.

Main Results:

• Men in high Cadmium (Cd) exposure areas exhibited higher semen Cadmium (Cd) levels and a reduced total motile sperm fraction.
• Semen Cadmium (Cd) levels correlated significantly with Cadmium (Cd) detected on sperm heads and necks.
• In vitro Cadmium (Cd) exposure reduced sperm progressive motility; tested scavenging agents did not restore motility.

Conclusions:

• Cadmium (Cd) directly accumulates in human sperm cells, impairing sperm function and motility.
• Reducing environmental Cadmium (Cd) exposure is the primary strategy to address Cadmium-induced reproductive issues.