Effects of a saturated fat and high cholesterol diet on memory and hippocampal morphology in the middle-aged rat.
Diets rich in cholesterol and/or saturated fats have been shown to be detrimental to cognitive performance. Therefore, we fed a cholesterol (2%) and saturated fat (hydrogenated coconut oil, Sat Fat 10%) diet to 16-month old rats for 8 weeks to explore the effects on the working memory performance of middle-aged rats. Lipid profiles revealed elevated plasma triglycerides, total cholesterol, HDL, and LDL for the Sat-Fat group as compared to an iso-caloric control diet (12% soybean oil). Weight gain and food consumption were similar in both groups. Sat-Fat treated rats committed more working memory errors in the water radial arm maze, especially at higher memory loads. Cholesterol, amyloid-beta peptide of 40 (Abeta40) or 42 (Abeta42) residues, and nerve growth factor in cortical regions was unaffected, but hippocampal Map-2 staining was reduced in rats fed a Sat-Fat diet, indicating a loss of dendritic integrity. Map-2 reduction correlated with memory errors. Microglial activation, indicating inflammation and/or gliosis, was also observed in the hippocampus of Sat-Fat fed rats. These data suggest that saturated fat, hydrogenated fat and cholesterol can profoundly impair memory and hippocampal morphology.
Granholm
Ann-Charlotte
AC
Department of Neurosciences and the Center on Aging, Medical University of South Carolina, Charleston, SC 29425, USA. granholm@musc.edu
Bimonte-Nelson
Heather A
HA
Moore
Alfred B
AB
Nelson
Matthew E
ME
Freeman
Linnea R
LR
Sambamurti
Kumar
K
D000367:Age Factors; D000818:Animals; D002540:Cerebral Cortex / Q000473:pathology; D002784:Cholesterol / Q000097:blood; D002791:Cholesterol, Dietary / Q000009:adverse effects*; D008076:Cholesterol, HDL / Q000097:blood; D000074263:Coconut Oil; D003463:Cues; D004041:Dietary Fats / Q000009:adverse effects*; D005227:Fatty Acids / Q000009:adverse effects*; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D018782:Maze Learning / Q000502:physiology*; D008570:Memory, Short-Term / Q000502:physiology*; D018715:Microscopy, Video; D009949:Orientation / Q000502:physiology; D010938:Plant Oils / Q000009:adverse effects; D051381:Rats; D011916:Rats, Inbred F344; D012153:Retention, Psychology / Q000502:physiology*; D014280:Triglycerides / Q000097:blood
D002791:Cholesterol, Dietary; D008076:Cholesterol, HDL; D004041:Dietary Fats; D005227:Fatty Acids; D010938:Plant Oils; D014280:Triglycerides; D002784:Cholesterol; D000074263:Coconut Oil