Induction of embryonic dysmorphogenesis by high glucose concentration, disturbed inositol metabolism, and inhibited protein kinase C activity

Publisher Website
Google Scholar
Abstract
Background Exposure to a diabetic environment causes excess reactive oxygen species (ROS), decreased prostaglandin E2 (PGE2) concentration, and increased embryonic maldevelopment. The aim of the present work was to study whether embryonic dysmorphogenesis is also dependent on alterations of inositol and associated intracellular metabolites. Methods Day 9 rat embryos were cultured for 24 or 48 hr and evaluated for gene expression. Day 10 and day 11 embryos from normal and diabetic rats were also examined. RT‐PCR was used to study embryonic gene expression of protein kinase C (PKC) and cytosolic phospholipase A2 (cPLA2). Results Embryos exposed to 30 mmol/L glucose (30G), 500 or 750 μmol/L of scyllo‐inositol (500SI or 750SI) had higher malformation score than control embryos cultured in 10 mmol/L glucose (10G). Adding 1.6 mmol/L inositol to the 30G or 750SI culture medium partly corrected these embryos, and completely normalized 500SI embryonic development. Adding 0.5 mmol/L N‐acetylcysteine (NAC) or 280 nmol/L PGE2 protected, and failed to protect, the SI‐exposed embryos, respectively. 10G embryos exposed to the PKC inhibitor GF‐109203X displayed dose‐dependent dysmorphogenesis. Addition of 1.6 mmol/L inositol or 0.5 mmol/L NAC to the PKC‐inhibitor‐exposed 10G embryos largely normalized the outcome, whereas PGE2 again failed to protect embryonic development. 30G culture tended to decrease the expression of cPLA2 after 24 hr in vitro. We also found decreased mRNA levels of cPLA2 in offspring of diabetic rats on gestational day 10 and of PKC on day 11, as compared with normal offspring. Conclusions High glucose concentration causes dysmorphogenesis in embryos by an interaction of oxidative stress and inositol depletion. Teratology 63:193–201, 2001.
Funding Information
  • Ernfors Family Fund
  • Söderberg Foundation
  • Swedish Diabetes Association
  • Novo Nordisk Foundation
  • Swedish Medical Research Council (12X-7475, 12X-109)

This publication has 47 references indexed in Scilit: