Related Experiment Video
Updated: Aug 19, 2026

Flow Cytometric Analysis of Biomarkers for Detecting Human Sperm Functional Defects
Published on: April 21, 2022
Quantitative study of caspase-3 activity in semen and after swim-up preparation in relation to sperm quality
Carolina Almeida1, Margarida F Cardoso, Mário Sousa
1Department of Genetics, Faculty of Medicine, University of Porto, Portugal.
Background:
There are no studies relating the apoptotic marker caspase-3 in human sperm to different degrees of abnormal sperm concentration, morphology and rapid progressive motility.
Methods:
Semen from 67 males with abnormal semen analyses (n = 61) and normozoospermia (n = 6) were used. In each case, sperm from the neat semen (semen fraction) and after gradient centrifugation and swim-up (swim-up fraction) were incubated with a caspase-3 profluorogenic substrate. Caspase-3 activity was quantified in 119 850 sperm, 67 488 from semen and 52 362 from swim-up fractions. Logistic regression was used to estimate odds ratio (with 99% confidence intervals) for the presence of caspase-3-positive sperm.
Results:
In semen fractions, no relationship was found between abnormal semen analysis subgroups and sperm caspase-3 activity. On the contrary, a significantly increased number of sperm with caspase-3 activity was found in the swim-up fractions from samples with poor sperm morphology. When analysis was restricted to single semen analysis defects, a significant increase of caspase-3-positive sperm was found in the semen fractions of cases with asthenozoospermia, and in the swim-up fractions of cases with teratozoospermia.
Conclusions:
Sperm caspase-3 activity seems to be associated with teratozoospermia and asthenozoospermia, thus suggesting that nuclear, mitochondrial and cytoskeletal abnormalities induce caspase-3 activation during spermiogenesis or sperm maturation.
