Dietary trans-fat combined with monosodium glutamate induces dyslipidemia and impairs spatial memory.
OBJECTIVE
Recent evidence suggests that intake of excessive dietary fat, particularly saturated fat and trans-hydrogenated oils (trans-fatty acids: TFA) can impair learning and memory. Central obesity, which can be induced by neonatal injections of monosodium Glutamate (MSG), also impairs learning and memory. To further clarify the effects of dietary fat and MSG, we treated C57BL/6J mice with either a TFA-enriched diet, dietary MSG, or a combination of both and examined serum lipid profile and spatial memory compared to mice fed standard chow. Spatial learning was assessed at 6, 16 and 32 weeks of age in a Morris Water Maze (MWM). The subjects were given four days of training to find a hidden platform and a fifth day of reversal learning, in which the platform was moved to a new location.


RESULTS
The TFA+MSG combination caused a central adiposity that was accompanied by impairment in locating the hidden platform in the MWM. Females in the TFA+MSG group showed a greater impairment compared to the other diet groups, and also showed elevated levels of fasting serum LDL-C and T-CHOL:HDL-C ratio, together with the lowest levels of HDL-C. Similarly, males in the TFA+MSG diet group were less successful than control mice at locating the hidden platform and had the highest level of abdominal adiposity and elevated levels of fasting serum LDL-C.


CONCLUSIONS
Dietary trans-fat combined with MSG increased central adiposity, promoted dyslipidemia and impaired spatial learning.
Collison
Kate S
KS
Cell Biology & Diabetes Research Unit, Department of Biological & Medical Research, King Faisal Specialist Hospital & Research Centre, P.O. BOX 3354, Riyadh 11211, Saudi Arabia. kate@kfshrc.edu.sa
Makhoul
Nadine J
NJ
Inglis
Angela
A
Al-Johi
Mohammed
M
Zaidi
Marya Zia
MZ
Maqbool
Zakia
Z
Saleh
Soad M
SM
Bakheet
Razan
R
Mondreal
Rhea
R
Al-Rabiah
Rana
R
Shoukri
Mohammed
M
Milgram
Norton W
NW
Al-Mohanna
Futwan A
FA
D050154:Adiposity; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002784:Cholesterol / Q000097:blood; D004041:Dietary Fats / Q000009:adverse effects*; D050171:Dyslipidemias / Q000139:chemically induced* / Q000523:psychology; D004435:Eating / Q000187:drug effects; D005260:Female; D008297:Male; D018782:Maze Learning / Q000187:drug effects*; D008569:Memory Disorders / Q000139:chemically induced*; D051379:Mice; D008810:Mice, Inbred C57BL; D012727:Sex Characteristics; D012970:Sodium Glutamate / Q000009:adverse effects* / Q000494:pharmacology; D044242:Trans Fatty Acids / Q000009:adverse effects* / Q000494:pharmacology
D004041:Dietary Fats; D044242:Trans Fatty Acids; D002784:Cholesterol; D012970:Sodium Glutamate