THE ONSET OF MATERNAL DIABETES IN SWINE INDUCES ALTERATIONS IN THE DEVELOPMENT OF THE FETAL PREADIPOCYTE

Diabetes induced during gestation has previously been demonstrated to increase adipose accretion in the fetal pig. The present experiment ex amined whether maternal diabetes alters the proliferation and differen tiation of the fetal preadipocyte. Seven crossbred gilts were injected with alloxan (50 mg/kg) at d 75 of gestation to induce diabetes and s even additional gilts were injected with buffer (controls). All gilts underwent Caesarean section of d 105 of gestation. Cells obtained from adipose tissue of fetuses of diabetic swine (FDS) at d 105 of gestati on demonstrated a greater (P < .05) proliferative response (57%) and h igher (P < .05) rates of differentiation as determined by sn-glycerol- 3-phosphate dehydrogenase (142% increase) and lipoprotein lipase (80% increase) activities than cells acquired from fetuses of control swine (FCS). Adipogenic activity of the sera from these two groups of fetus es did not differ when tested on adipose tissue from fetuses at 105 dr of gestation. However, use of these sera on cells derived from normal fetuses at 75 d of gestation resulted in detection of an increase (P < .05) in adipogenic activity within the sera from FDS. This study sug gests that maternal diabetes causes alterations in the preadipocyte fr action of cells within the developing adipose tissue that result in fo rmation of more adipocytes and thus permits greater capacity for lipid accumulation in the growing fetus of the diabetic pig. These alterati ons in the preadipocyte result from the activity of factors that trans itionally function during the latter half of gestation.