Effect of post-ischemic caloric restriction on cell death and functional recovery

Abstract

Since caloric restriction (CR) can modify multiple pathways central to the ischemic cascade and enhance neuroplasticity mechanisms, we hypothesized that CR should exert protective effects following brain ischemia. Previous studies have suggested benefit when CR was administered prior to ischemia. This study investigated whether prolonged CR beginning after global ischemia would result in lasting protection as assessed by performance in the open field, as a measure of functional outcome, and hippocampal CA1 neuronal counts. Adult male Mongolian gerbils were subjected to five minute bilateral carotid artery occlusion (I) or sham surgery (S) with tympanic temperature maintained at 36.5 ± 0.2ºC during the intra-ischemic period. After screening out gerbils with incomplete ischemia, each of the two surgical groups were randomly assigned to control diet (CON) or 30% CR for the duration of the study (60d). Gerbils were tested in the open field on d3, 7, 10, 30 and 60. Ischemic animals on control diet showed a significantly higher level of activity in the open field (impaired habituation) compared to SCON gerbils on all test days (p