Cyclic FEE Peptide Improves Human Sperm Movement Parameters without Modification of Their Energy Metabolism

Area of Science:

• Reproductive Biology
• Sperm Physiology
• Mitochondrial Function

Background:

• Cyclic fertilin peptide (cFEE) is known to improve human gamete interaction.
• The precise mechanism by which cFEE enhances interaction, particularly concerning sperm function, remains unclear.

Purpose of the Study:

• To investigate if cyclic fertilin peptide (cFEE) improves sperm movement parameters and mitochondrial ATP production.
• To elucidate the role of cFEE in sperm bioenergetics and motility.

Main Methods:

• Computer-assisted sperm analysis (CASA) was used to assess sperm movement parameters in patients' samples treated with cFEE.
• Mitochondrial functions, including ATP production, respiration, and mitochondrial membrane potential (MMP), were evaluated in donor sperm incubated with cFEE using bioluminescence, high-resolution oxygraphy, and flow cytometry.

Main Results:

• cFEE significantly improved sperm movement parameters and the percentage of hyperactivated sperm.
• Oxidative phosphorylation (OXPHOS) was identified as the primary energy source for sperm motility.
• No significant impact of cFEE was observed on analyzed mitochondrial bioenergetic parameters.

Conclusions:

• Cyclic fertilin peptide (cFEE) enhances sperm motility and hyperactivation.
• The beneficial effects of cFEE on sperm function may stem from a more efficient utilization of existing energy resources rather than increased mitochondrial ATP production.