Soy lecithin interferes with mitochondrial function in frozen-thawed ram spermatozoa

Area of Science:

• Animal reproduction and biotechnology
• Sperm cryopreservation
• Membrane biophysics

Background:

• Egg yolk and milk are common cryoprotectants for semen preservation.
• Concerns exist regarding disease transmission from animal-derived cryoprotectants.
• Lecithin is explored as a safer, plant-derived alternative.

Purpose of the Study:

• To evaluate soy lecithin as an alternative to egg yolk for ram semen cryopreservation.
• To assess lecithin's effect on sperm viability, motility, apoptosis, and mitochondrial function.
• To investigate sublethal cryopreservation damage using mitochondrial markers.

Main Methods:

• Ram semen cryopreservation in Tris-citrate-glucose, soy lecithin, or egg yolk media.
• Assessment of sperm viability, motility, apoptosis, and mitochondrial function (MIMS, MIMP, cell membrane potential).
• Post-thaw incubation to reveal delayed functional changes.

Main Results:

• Lecithin protected some sperm quality aspects but induced mitochondrial membrane potential loss.
• Soy lecithin samples showed decreased MIMS and MIMP, with lower motility post-thaw compared to egg yolk.
• Further incubation revealed sublethal mitochondrial damage in lecithin-treated samples.

Conclusions:

• Lecithin may impact the inner mitochondrial membrane in cryopreserved spermatozoa.
• Mitochondrial membrane alterations are sensitive indicators of sublethal damage missed by standard analyses.
• Targeting mitochondrial function could improve semen cryopreservation protocols.