Diabetic teratogenesis. In vitro evidence for a multifactorial etiology with little contribution from glucose per se.
To determine the extent to which elevated glucose and 3-hydroxybutyrate (3OHB) concentrations contribute to the embryotoxic properties of diabetic serum, we tested the effects of serum from untreated or acutely insulin-treated diabetic rats on the development of mouse embryos during neurulation in vitro. Male Sprague-Dawley rats (n = 143) with streptozocin-induced diabetes for 1 week received infusions of insulin (n = 105) or saline (n = 38) for up to 120 min. The insulin-infused animals were exsanguinated when serum glucose concentrations fell to between 5.6 and 8.3 mM. Saline-infused animals were exsanguinated after a similar duration of infusion. Serum samples were tested for embryotoxic effects on 3-6 somite mouse embryos cultured in vitro for 24 h. Of embryos cultured in serum from untreated diabetic animals (glucose: 24 +/- 1 mM; 3OHB: 2.0 +/- 0.3 mM), 36% (31 of 87) exhibited gross malformations, mostly of the neural tube. Only 16% (10 of 62) of embryos grown in serum from acutely insulin-treated animals (glucose: 7.4 +/- 0.2 mM; 3OHB: 0.20 +/- 0.06 mM) were malformed. This rate that was less than half the rate caused by exposure to diabetic serum (P < 0.01), but a rate that remained much greater than the rate associated with culture in normal serum (0% in this study; < 2% historically). In vitro addition of glucose to serum from insulin-treated animals to re-establish hyperglycemia in the diabetic range (25 mM) resulted in a 17% (12 of 70) malformation rate, nearly identical to the 16% rate caused by normoglycemic serum from insulin-treated animals.(ABSTRACT TRUNCATED AT 250 WORDS)
Buchanan
T A
TA
Department of Medicine, University of Southern California School of Medicine, Los Angeles.
Denno
K M
KM
Sipos
G F
GF
Sadler
T W
TW
D020155:3-Hydroxybutyric Acid; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D000013:Congenital Abnormalities / Q000209:etiology*; D003921:Diabetes Mellitus, Experimental / Q000097:blood* / Q000188:drug therapy; D005260:Female; D006885:Hydroxybutyrates / Q000097:blood* / Q000633:toxicity; D007328:Insulin / Q000627:therapeutic use*; D008297:Male; D009436:Neural Tube Defects / Q000209:etiology*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013723:Teratogens
D001786:Blood Glucose; D006885:Hydroxybutyrates; D007328:Insulin; D013723:Teratogens; D020155:3-Hydroxybutyric Acid