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Updated: May 29, 2026
05:44
Medium-throughput Screening Assays for Assessment of Effects on Ca2+-Signaling and Acrosome Reaction in Human Sperm
Published on: March 1, 2019
Effect of relaxin on human sperm functions
Alberto Ferlin1, Massimo Menegazzo, Lisa Gianesello
1University of Padova, Department of Histology, Microbiology and Medical Biotechnologies, Section of Clinical Pathology and Center for Male Gamete Cryopreservation, Padova, Italy.
Journal of Andrology
|September 10, 2011
Summary
Relaxin hormone, found in high concentrations in seminal fluid, enhances sperm motility, mitochondrial function, and acrosome reaction by binding to its receptor RXFP1.
Area of Science:
- Reproductive Biology
- Endocrinology
- Sperm Physiology
Background:
- Relaxin is a hormone with known reproductive functions in females.
- Its role in male reproduction and human sperm function is not well-established.
- Previous studies on relaxin's effects on sperm yielded conflicting results.
Purpose of the Study:
- To investigate the presence and function of the relaxin receptor RXFP1 in human spermatozoa.
- To determine the effects of relaxin on various human sperm functions.
- To assess the potential of relaxin in improving sperm quality for assisted reproduction.
Main Methods:
- Detection of RXFP1 expression in human spermatozoa using immunofluorescence.
- In vitro analysis of sperm motility, mitochondrial activity, apoptosis, hyperactivation, intracellular calcium, cAMP levels, and acrosome reaction.
- Measurement of relaxin concentrations in blood and seminal plasma.
- Blocking experiments using anti-RXFP1 antibodies.
Main Results:
- RXFP1 is expressed in human spermatozoa, primarily localized in the astrodome.
- Relaxin treatment improved sperm motility, maintained mitochondrial activity, and reduced apoptosis.
- Relaxin increased sperm hyperactivation, intracellular calcium and cAMP, and induced acrosome reaction, effects blocked by anti-RXFP1 antibody.
- Relaxin levels were significantly higher in seminal plasma than in blood.
Conclusions:
- Relaxin positively influences key human sperm functions essential for fertilization.
- Relaxin preserves sperm functionality, suggesting a significant role in male reproductive health.
- Relaxin may hold practical value for improving outcomes in assisted reproduction techniques.
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