Glucose transporter 8 expression and translocation are critical for murine blastocyst survival

Anil B. Pinto, Mary O. Carayannopoulos, Amanda Hoehn, Lia Dowd, Kelle H. Moley

Research output: Contribution to journalArticlepeer-review

82 Scopus citations

Abstract

Glucose transporter (GLUT) 8 is an insulin-responsive facilitative glucose transporter expressed predominantly in the murine blastocyst. To determine the physiologic role of GLUT8, two-cell embryos were cultured to a blastocyst stage in antisense or sense oligonucleotides to GLUT8. Apoptosis was assessed using the TUNEL techniques and recorded as the percentage of TUNEL-positive nuclei/total nuclei. Embryos cultured in GLUT8 antisense experienced increased TUNEL-positive nuclei, whereas sense embryos did not. Embryos cultured in a control AS oligonucleotide, specific for heat shock protein 70-2, showed a rate of apoptosis similar to sense. To determine the outcome of these apoptotic embryos, blastocysts exposed to sense vs. anti-sense were transferred back into foster mice and the pregnancy continued until Day 14.5, at which time the uteri were examined for normal gestational sacs and resorptions. Embryos exposed to GLUT8 antisense experienced higher rates of resorptions and lower normal pregnancy rates compared to embryos cultured in GLUT8 sense. To examine the insulin growth factor (IGF)-1/insulin intracellular signaling pathways involved in GLUT8 translocation, IGF-1 receptor (IGF-1R) expression was decreased in the blastocysts with antisense oligonucleotides. Using confocal immunofluorescent microscopy, GLUT8 translocation in response to insulin was observed. Exposure to insulin in the embryos exposed to IGF-1R sense induced translocation of GLUT8 from intracellular compartments to the plasma membrane. Blastocysts exposed to IGF-1R antisense, however, failed to demonstrate any change in the intracellular location of GLUT8 with insulin treatment. The IGF-1R antisense embryos also displayed significantly greater TUNEL staining compared to sense embryos. These data suggest that GLUT8 expression and translocation in response to insulin are critical for blastocyst survival.

Original languageEnglish
Pages (from-to)1729-1733
Number of pages5
JournalBiology of reproduction
Volume66
Issue number6
DOIs
StatePublished - 2002

Keywords

  • Apoptosis
  • Early development
  • Embryo
  • Insulin
  • Insulin-like growth factor receptor

Fingerprint

Dive into the research topics of 'Glucose transporter 8 expression and translocation are critical for murine blastocyst survival'. Together they form a unique fingerprint.

Cite this