Association between total globozoospermia and sperm chromatin defects.

Area of Science:

• Reproductive Biology
• Human Genetics
• Infertility Research

Background:

• Globozoospermia is a severe sperm defect characterized by round-headed spermatozoa lacking an acrosomal cap.
• It causes primary infertility and low fertilization rates even with intracytoplasmic sperm injection (ICSI) and artificial oocyte activation (AOA).
• Previous studies suggest fertilization failure may involve factors beyond oocyte activation, such as sperm chromatin integrity.

Purpose of the Study:

• To compare sperm protamine deficiency and DNA fragmentation in men with total globozoospermia versus fertile individuals.
• To investigate the role of sperm DNA damage in fertilization failure post-ICSI-AOA.
• To identify potential therapeutic targets for improving fertility outcomes in globozoospermia.

Main Methods:

• Sperm samples from 30 infertile men with 100% globozoospermia and 22 fertile men were analyzed.
• Chromomycin A3 staining was used to assess protamine deficiency.
• TUNEL assay was employed to evaluate sperm DNA fragmentation.

Main Results:

• Men with globozoospermia exhibited significantly lower sperm concentration and motility.
• A higher percentage of sperm abnormal morphology, protamine deficiency, and DNA fragmentation was observed in globozoospermic men.
• These findings indicate increased sperm DNA damage in globozoospermia.

Conclusions:

• Defective DNA compaction and increased sperm DNA damage are likely contributors to infertility in globozoospermia.
• Antioxidant therapy prior to ICSI-AOA may be a beneficial strategy to improve fertilization rates.
• Further research is warranted to explore the efficacy of antioxidant treatments in globozoospermic patients.