2012 Annual Report
1a.Objectives (from AD-416):
1: Determine the effects of the radiation on several cognitive and motor behaviors (e.g., Morris water maze), and in addition examine additional new ones (e.g., elevated + maze).
2: Determine whether pre-feeding with Blueberry (BB) or Strawberry (SB) at 2-4% of the diet will prevent the radiation induced deficits in these parameters.
3: We will utilize several techniques (see approach) to assess the changes in several markers of phosphorylation that are important in cell signaling and neurogenesis.
1b.Approach (from AD-416):
The effects of Strawberry (SB) and/or Blueberry (BB) dietary supplementations (8 wks)(control, 2% BB, 2% SB or 1% each SB/BB extracts in the diet for 8 weeks) will be examined in non-irradiated or irradiated (4 mo Sprague Dawley) rats using cognitive and motor tasks. The tests utilized will be age-sensitive motor (inclined screen) and cognitive behaviors (Morris water maze performance, elevated plus maze, sensorimotor gating). We will then determine the effects of the supplementations on neuronal signaling and correlate these with alterations in behavioral parameters determined. We will utilize several techniques (e.g., Western blot analyses and immunocytochemistry) to assess the changes in several markers of phosphorylation that are important in cell communication and neurogenesis (e.g., calcium-dependent protein kinase C, PKC; extracellular signal regulated kinases, ERK).
In collaboration with a scientist from UMBC we studied the effects of cosmic rays such as charged oxygen and iron particle radiation in young animals. The study has shown that cosmic rays cause “accelerated aging”, where young animals develop cognitive and neurobiological deficits that are characteristic of much older animals. In continuation of our previous findings regarding memory loss due to radiation exposure, we discovered that cosmic rays cause loss of “natural housekeeping” (autophagy) function in the brain leading to the accumulation of toxic biological materials (damaged proteins and organelles) followed by progressive deterioration and death of brain cells (neurons). Loss of neuronal housekeeping was also accompanied by increased oxidative stress, inflammation, and altered cell communication and neurogenesis. We published a manuscript detailing these results in the journal Radiation Research. Subsequent investigations also revealed that cosmic rays caused an increase in the number of insoluble tau inclusions in neurons which are highly toxic in nature, and we have presented these results at national scientific meetings. In subsequent studies to explore the effects of diets containing either 2% blueberry or 2% strawberries in preventing the adverse effects of cosmic rays, we found that berries reduced oxidative stress, inflammation and loss of neuronal housekeeping function in brain. The results have been presented at national meetings, and the manuscript is being prepared. We are currently conducting studies to explore the effects of diets on disease-related proteins.