N-Acetylcysteine and alpha-cyano-4-hydroxycinnamic acid alter protein kinase C (PKC)-delta and PKC-zeta and diminish dysmorphogenesis in rat embryos cultured with high glucose in vitro.
Malformations and growth disturbances are two- to threefold more common in infants of diabetic mothers than in offspring of non-diabetic pregnancy. Several suggestions have emerged to explain the reasons for diabetic embryopathy, including enhanced mitochondrial production of reactive oxygen species leading to altered activation of protein kinase C. This study aimed to evaluate the effect of alpha-cyano-4-hydroxycinnamic acid (CHC) and N-acetylcysteine (NAC) addition on morphology and activity of protein kinase C-delta and protein kinase C-zeta in rat embryos exposed to a high glucose concentration in vitro. Day 9 embryos from normal rats were cultured in 10 or 30 mM glucose concentrations with or without supplementation of CHC, NAC, or protein kinase C inhibitors specific for protein kinase C-delta and protein kinase C-zeta. Embryos were evaluated for malformations, crown rump length, and somite number. Protein kinase C-delta and protein kinase C-zeta activities were estimated by western blot by separating membranous and cytosolic fractions of the embryo. We found increased malformations and growth retardation in embryos cultured in high versus low glucose concentrations. These abnormalities were diminished when CHC and NAC or specific protein kinase C-inhibitors were added to the culture medium. The activities of embryonic protein kinase C-delta and protein kinase C-zeta were increased in the high glucose environment after 24-h culture, but were normalized by the addition of CHC and NAC as well as respective inhibitor to the culture medium. These findings suggest that mitochondrial overproduction of reactive oxygen species is involved in diabetic embryopathy. Furthermore, such overproduction may affect embryonic development, at least partly, by enhancing the activities of protein kinase C-delta and protein kinase C-zeta.
Gäreskog
Mattias
M
Department of Medical Cell Biology, Biomedical Center, Uppsala University, SE-751 23 Uppsala, Sweden. mattias.gareskog@mcb.uu.se
Wentzel
Parri
P
D000098:Acetophenones / Q000494:pharmacology; D000111:Acetylcysteine / Q000494:pharmacology*; D000818:Animals; D001578:Benzopyrans / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects; D000013:Congenital Abnormalities / Q000201:enzymology / Q000517:prevention & control*; D003373:Coumaric Acids / Q000494:pharmacology*; D003470:Culture Media; D046508:Culture Techniques; D016640:Diabetes, Gestational / Q000201:enzymology*; D005260:Female; D016166:Free Radical Scavengers / Q000494:pharmacology*; D005947:Glucose / Q000494:pharmacology; D015151:Immunoblotting / Q000379:methods; D008928:Mitochondria / Q000378:metabolism; D023421:Models, Animal; D009842:Oligopeptides / Q000494:pharmacology; D011247:Pregnancy; D011493:Protein Kinase C / Q000032:analysis / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051745:Protein Kinase C-delta / Q000032:analysis / Q000037:antagonists & inhibitors / Q000378:metabolism; D011773:Pyruvates / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000032:analysis; D000099221:Protein Kinase C zeta
D000098:Acetophenones; D000111:Acetylcysteine; D001578:Benzopyrans; D003373:Coumaric Acids; D003470:Culture Media; D016166:Free Radical Scavengers; D005947:Glucose; D009842:Oligopeptides; D011493:Protein Kinase C; D051745:Protein Kinase C-delta; D011773:Pyruvates; D017382:Reactive Oxygen Species; D000099221:Protein Kinase C zeta; C444219:myristoylated-arginyl-arginyl-glycyl-alanyl-arginyl-arginyl-tryptophyl-arginyl-lysine; C007175:alpha-cyano-4-hydroxycinnamate; C085746:rottlerin