Ontogeny and the effects of in utero brain ischemia on interleukin-1β and interleukin-6 protein expression in ovine cerebral cortex and white matter

Interleukin (IL)-1 beta and IL-6 have been implicated in brain development, injury progression, and fetal/maternal immune interactions. We examined IL-1 beta and IL-6 protein expression in cerebral cortex (CC) and white matter (WM) from non-ischemic ovine fetuses at 87-90,122-127, and 135-137 days of gestation, pregnant ewes at 87-90 and 135-137 days of gestation, and fetuses exposed to 48 or 72 h of reperfusion after ischemia. Protein expression was determined by Western immunoblot. In non-ischemic CC, IL-1 beta was higher (P < 0.05) in adult sheep and fetuses at 135-137 than 87-90 and 122-127 days, and IL-6 higher at 122-127 than 87-90 days, and in adults than fetuses at 87-90,122-127, and 135-137 days of gestation. In non-ischemic fetal WM, IL-6 was higher at 135-137 than 87-90 days, but IL-1 beta did not differ. In CC, IL-1 beta was higher in ewes at 135-137 than 87-90 days and IL-6 at 135-137 days and in non-pregnant adults than ewes at 87-90 days of gestation. In WM, IL-1 beta was higher in ewes at 135-137 than 87-90 days of gestation, but IL-6 did not differ. Forty-eight and 72 h after ischemia, CC IL-1 beta was higher than in non-ischemic fetuses. Seventy-two hours after ischemia, IL-1 beta and IL-6 were higher in WM than CC. In conclusion, IL-1 beta and IL-6 exhibit developmental regulation in fetal brain, change during gestation in brains of pregnant ewes, show regional differences in normal brains of fetuses and ewes, demonstrate differential responses after ischemia in CC and WM, and IL-1 beta but not IL-6 increases after ischemia in CC. (C) 2012 ISDN. Published by Elsevier Ltd. All rights reserved.