Physiologically detectable bisphenol A impairs human sperm functions by reducing protein-tyrosine phosphorylation

Area of Science:

• Environmental Science
• Reproductive Biology
• Toxicology

Background:

• Bisphenol A (BPA) is a common plasticizer found in human bodily fluids at concentrations of 0.1–10 nM.
• Previous studies showed low BPA concentrations (0.001 nM) inhibit mouse sperm function.
• The impact of physiologically relevant BPA levels on human sperm remains unclear.

Purpose of the Study:

• To investigate the effects of BPA on human sperm viability, motility, hyperactivation, and capacitation.
• To explore the underlying mechanisms of BPA's impact on human sperm function.

Main Methods:

• Human sperm were exposed to various BPA concentrations (0–10³ nM).
• Sperm viability, kinematic parameters, hyperactivation, and capacitation were assessed.
• Protein tyrosine phosphorylation and sperm calcium signaling were analyzed.

Main Results:

• BPA significantly reduced human sperm viability, motility, progressive motility, hyperactivation, and capacitation.
• BPA suppressed protein tyrosine phosphorylation in human sperm.
• No effect of BPA was observed on sperm calcium signaling.

Conclusions:

• Physiologically relevant BPA concentrations impair human sperm function.
• BPA may affect male fertility by inhibiting protein tyrosine phosphorylation in sperm.
• Environmental BPA exposure could be a contributing factor to male infertility.