The human sperm proteome-Toward a panel for male fertility testing

Area of Science:

• Reproductive Biology
• Proteomics
• Molecular Medicine

Background:

• Male factor contributes significantly to infertility, yet detailed molecular causes remain poorly understood.
• A molecular diagnosis is often unavailable for men experiencing infertility.

Purpose of the Study:

• To achieve higher resolution of the human sperm proteome for a better understanding of male infertility.
• To investigate the molecular basis of reduced fertility despite normal sperm appearance and identify involved proteins.

Main Methods:

• Mass spectrometry was used to analyze proteomic profiles of spermatozoa from 76 men with varying fertility statuses.
• Infertile men had abnormal semen parameters, while fertile men exhibited normozoospermia.

Main Results:

• Approximately 7000 coding genes were identified in the sperm proteome, primarily related to motility, response to stimuli, adhesion, and reproduction.
• The number of sperm proteins with significantly deviating abundances increased with the severity of infertility (oligozoospermia to oligoasthenoteratozoospermia).
• Deregulated proteins were mainly involved in flagellar assembly, sperm motility, fertilization, and male gametogenesis, forming a network related to male infertility.

Conclusions:

• The study illuminates the molecular basis for the dysfunction of fewer spermatozoa in oligozoospermia and related conditions.
• A presented network of male infertility genes and proteins may aid in further understanding the molecular mechanisms of male infertility.