Effect of Antioxidants and Apoptosis Inhibitors on Cryopreservation of Murine Germ Cells Enriched for Spermatogonial Stem Cells

PLoS One. 2016 Aug 22;11(8):e0161372. doi: 10.1371/journal.pone.0161372. eCollection 2016.

Abstract

Spermatogonial stem cells (SSCs) are germline stem cells that serve as the foundation of spermatogenesis to maintain fertility throughout a male's lifetime. To treat male infertility using stem cell banking systems and transplantation, it is important to be able to preserve SSCs for long periods of time. Therefore, this study was conducted to develop an optimal cryopreservation protocol for SSCs using antioxidants and apoptosis inhibitors in freezing medium. No differences were observed compared to controls when SSCs were cryopreserved in the presence of apoptosis inhibitors by themselves. However, mouse germ cells cryopreserved in basal medium containing the antioxidant hypotaurine (14 mM) resulted in significantly greater proliferation potential and mitochondrial activity. Furthermore, treatment groups with combinations containing 200 mM trehalose and 14 mM hypotaurine showed higher proliferation rates compared to controls. In addition, several serum free conditions were evaluated for SSC cryopreservation. Treatment media containing 10% or 20% knockout serum replacement resulted in similar cryopreservation results compared to media containing FBS. SSC transplantation was also performed to confirm the functionality of SSCs frozen in 14 mM hypotaurine. Donor SSCs formed normal spermatogenic colonies and sperm in the recipient testis. These data indicate that inclusion of 14 mM hypotaurine in cryopreservation media is an effective way to efficiently cryopreserve germ cells enriched for SSCs and that knockout serum replacement can replace FBS in germ cell cryopreservation media.

MeSH terms

  • Animals
  • Antioxidants / pharmacology*
  • Cell Proliferation / drug effects
  • Cryopreservation / methods*
  • Cryoprotective Agents / pharmacology*
  • Gene Expression
  • Genes, Reporter
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • Sericins / pharmacology
  • Serum / chemistry
  • Spermatogenesis / drug effects
  • Spermatogenesis / genetics
  • Spermatogonia / cytology
  • Spermatogonia / drug effects*
  • Spermatogonia / metabolism
  • Spermatogonia / transplantation
  • Taurine / analogs & derivatives*
  • Taurine / pharmacology
  • Testis / cytology
  • Testis / metabolism
  • Trehalose / pharmacology*

Substances

  • Antioxidants
  • Cryoprotective Agents
  • Sericins
  • enhanced green fluorescent protein
  • Green Fluorescent Proteins
  • Taurine
  • hypotaurine
  • Trehalose

Grants and funding

This work was supported by the Korean Health Technology R&D Project, Ministry of Health and Welfare (HI12C0055), and Next-Generation BioGreen 21 Program (PJ011347), Republic of Korea. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.