Dietary Enrichment with Medium Chain Triglycerides (AC-1203) Elevates Polyunsaturated Fatty Acids in the Parietal Cortex of Aged Dogs: Implications for Treating Age-Related Cognitive Decline
Dogs demonstrate an age-related cognitive decline, which may be related to a decrease in the concentration of omega-3 polyunsaturated fatty acids (n-3 PUFA) in the brain. Medium chain triglycerides (MCT) increase fatty acid oxidation, and it has been suggested that this may raise brain n-3 PUFA levels by increasing mobilization of n-3 PUFA from adipose tissue to the brain. The goal of the present study was to determine whether dietary MCT would raise n-3 PUFA concentrations in the brains of aged dogs. Eight Beagle dogs were randomized to a control diet (n = 4) or an MCT (AC-1203) enriched diet (n = 4) for 2 months. The animals were then euthanized and the parietal cortex was removed for phospholipid, cholesterol and fatty acid determinations by gas-chromatography. Dietary enrichment with MCT (AC-1203) resulted in a significant increase in brain phospholipid and total lipid concentrations (P < 0.05). In particular, n-3 PUFA within the phospholipid, unesterified fatty acid, and total lipid fractions were elevated in AC-1203 treated subjects as compared to controls (P < 0.05). Brain cholesterol concentrations did not differ significantly between the groups (P > 0.05). These results indicate that dietary enrichment with MCT, raises n-3 PUFA concentrations in the parietal cortex of aged dogs.
KeywordsMedium chain triglycerides Brain Omega-3 polyunsaturated fatty acids (n-3 PUFA) Docosahexaenoic acid (DHA) Mobilization Cognition Alzheimer’s Aging Dogs
Medium chain triglycerides
Polyunsaturated fatty acids
We would like to thank Dr. Christa M. Studzinski for her assistance and Dr. David W.L. Ma for his support and expert advice. Financial support for this study was provided by the Natural Sciences and Engineering Research Council and Accera Inc. A.Y.T is a recipient of the Canadian Institutes of Health Research Doctoral Research Award (Fredrick Banting and Charles Best Canada Graduate Scholarships). The authors declare no conflict of interest.
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