Abstract 11954: Whole Body Periodic Acceleration (pGz) Decreases Hypoxia Induced Apoptotic Signaling in the Brain of Newborn Piglets
Hypoxic brain injury (HI) can be a devastating complication in neonates and infants, associated with apoptosis in vulnerable brain regions (e.g. cortex, hippocampus, striatum) where effective neuroprotective strategies are desperately needed. pGz is a method which moves the body in a repetitive head to foot motion adding pulses to the circulation increasing pulsatile shear stress. pGz is cardioprotective for myocardial ischemia when performed as pre-treatment in piglets and neuroprotective in a rat model of HI.
Objective: To determine whether pGz pre-treatment suppresses pro-apoptotic brain regulatory proteins induced by HI in neonatal piglets. Specifically, we hypothesized that 2 hrs pGz pretreatment would decrease apoptotic signaling in newborn brain cortex, hippocampus and striatum, by increasing pAkt expression and the ratio of Bcl-2/Bax.
Methods: Nine anesthetized (Fentanyl and Isoflurane) neonatal piglets (weight 2.5-3 kg) were randomly assigned to: 1) anesthesia alone (C), 2) one hour 7% FiO2 (HI), and recovery in 21% FiO2 for 2 hr, 3) 2hr pGz prior to HI (pGz), under the same recovery conditions. We measured expression of proteins that play well established roles in regulation of apoptosis Bax (pro-apoptotic) and pAkt, Bcl-2 and increased Bcl-2/Bax ratio (anti-apoptotic) in three specific brain regions (cortex, hippocampus, striatum). Expression of the above proteins was measured by immunoblotting. The results are mean integrated density (arbitrary units A.U). pAkt and ratio of Bcl-2/Bax expression increased in all regions of brain in pGz groups as compared with HI. (†p< 0.05 HI vs. pGz)
Conclusion: pGz pretreatment in a piglet model of HI decreases apoptotic signaling in all three brain regions, suggesting pGz as a novel, effective neuroprotective strategy when applied prior to procedures likely to involve Hypoxia Ischemia Injury.
- © 2011 by American Heart Association, Inc.