Біологічні студії (Dec 2018)

ATP-induced changes in [Ca2+]i in spermatozoa of infertile men with oligo- and asthenozoospermia

  • Fafula R.V.,
  • Meskalo О.I,
  • Lychkovskyy E.I.,
  • Vorobets Z.D.

DOI
https://doi.org/10.30970/sbi.1203.580
Journal volume & issue
Vol. 12, no. 3–4
pp. 47 – 54

Abstract

Read online

Calcium is the major second messenger which plays an important role in sperm physiology. A decreased fertility potential of spermatozoa is closely associated with the disturbances of Ca2-homeostasis. ATP is present in the female reproductive tract and may play an important role in the fertilization process. Since intracellular calcium ([Ca2+]i) is the main determinant of many physiological processes occurring in sperm, we set out to describe the Ca2+-signals in response to extracellular ATP (ATPe) in spermatozoa of fertile (normozoospermia) and infertile men (oligo- and asthenozoospermia). ATPe-induced changes in [Ca2+]i in spermatozoa were studied using 2 mM fluorescent probe Fluo-4. ATPe caused a rapid transient elevation in [Ca2+]i. We found that kinetics and magnitude of the [Ca2+]i changes induced by the ATPe were different in normo- and pathospermic cells. Specifically, the average value of peak amplitudes of [Ca2+]i rise induced by 5 mM ATPe in oligozoospermic samples was not significantly different from the normozoospermic samples. In the asthenozoospermic samples, the ATPe-induced peak amplitude of [Ca2+]i changes was in 1.5 fold lower (P<0.05) compared to that in the normozoospermic samples. ATPe-induced increase in [Ca2+]i in sperm cell has a concentration-dependent manner in both normozoospermic and pathozoospermic samples. In the oligozoospermic samples, the [Ca2+]i transient response was 2.5 fold (P<0.05) slower than in the normozoospermic samples. Differences in ATPe-induced [Ca2+]i transients between astheno- and normozoospermic samples were also significant (P<0.05) although less pronounced. The obtained results clearly demonstrate ATPe-induced increase in [Ca2+]i transients are disturbed in pathozoospermic samples which may be detrimental to sperm activation and may result in fertilization failure or abnormality. Taken into account the importance reproductive techniques, specifically for in vitro fertilization and intrauterine insemination present study suggest that modu­lation of [Ca2+]i signals and sperm function by the ATPe may be beneficial for artificial reproductive techniques used in reproductive biology and medicine.

Keywords