(S)-α-chlorohydrin inhibits protein tyrosine phosphorylation through blocking cyclic AMP - protein kinase A pathway in spermatozoa

PLoS One. 2012;7(8):e43004. doi: 10.1371/journal.pone.0043004. Epub 2012 Aug 20.

Abstract

α-Chlorohydrin is a common contaminant in food. Its (S)-isomer, (S)-α-chlorohydrin (SACH), is known for causing infertility in animals by inhibiting glycolysis of spermatozoa. The aim of present work was to examine the relationship between SACH and protein tyrosine phosphorylation (PTP), which plays a critical role in regulating mammalian sperm capacitation. In vitro exposure of SACH 50 µM to isolated rat epididymal sperm inhibited PTP. Sperm-specific glyceraldehyde 3-phosphate dehydrogenase (GAPDS) activities, the intracellular adenosine 5'-triphosphate (ATP) levels, 3'-5'-cyclic adenosine monophosphate (cAMP) levels and phosphorylation of protein kinase A (PKA) substrates in rat sperm were diminished dramatically, indicating that both glycolysis and the cAMP/PKA signaling pathway were impaired by SACH. The inhibition of both PTP and phosphorylation of PKA substrates by SACH could be restored by addition of cAMP analog dibutyryl-cAMP (dbcAMP) and phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX). Moreover, addition of glycerol protected glycolysis, ATP levels, phosphorylation of PKA substrates and PTP against the influence of SACH. These results suggested SACH inhibited PTP through blocking cAMP/PKA pathway in sperm, and PTP inhibition may play a role in infertility associated with SACH.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Animals
  • Cells, Cultured
  • Cyclic AMP / metabolism
  • Cyclic AMP-Dependent Protein Kinases / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Male
  • Phosphorylation / drug effects*
  • Rats
  • Signal Transduction / drug effects
  • Spermatozoa / drug effects*
  • Spermatozoa / metabolism*
  • Tyrosine / metabolism*
  • alpha-Chlorohydrin / pharmacology*

Substances

  • Tyrosine
  • Adenosine Triphosphate
  • alpha-Chlorohydrin
  • Cyclic AMP
  • Cyclic AMP-Dependent Protein Kinases

Grants and funding

This research was supported by grants from the National Natural Science Fund (No. 30571539 and 30972438), Shanghai Rising Star program (No. 03QD14011), Shanghai Municipal Health Bureau Leading Academic Discipline Project (No. 08GWD14), and Dawn Scholarship Project (No. 07SG01). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.