Brain and systemic glucose metabolism in the healthy elderly following fish oil supplementation

• Published in: Prostaglandins, leukotrienes and essential fatty acids Vol. 85; no. 5; pp. 287 - 291
• Main Authors: Nugent, S, Croteau, E, Pifferi, F, Fortier, M, Tremblay, S, Turcotte, E, Cunnane, S.C
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Kidlington Elsevier Ltd 01.11.2011; Elsevier
• Subjects: Adult; Advanced Basic Science; Aged; Aged, 80 and over; Aging - metabolism; Biological and medical sciences; Cerebellum - diagnostic imaging; Cerebellum - metabolism; Dietary Supplements; Endocrinology & Metabolism; Fatty Acids, Omega-3 - administration & dosage; Female; Fluorodeoxyglucose F18 - administration & dosage; Fundamental and applied biological sciences. Psychology; Glucose - metabolism; Humans; Life Sciences; Male; Positron-Emission Tomography; Radiography; Radiopharmaceuticals - administration & dosage; Vertebrates: endocrinology; CMRg; standardized uptake values; oral glucose tolerance test; cerebral metabolic rate of glucose; 18F-FDG; quantitative insulin sensitivity check index; HOMA-IR; 18fluorodeoxyglucose; homeostasis model of insulin resistance; QUICKI; SUV; docosahexaenoic acid; MMSE; positron emission tomography; DHA; OGTT; Mini-Mental State Examination; PET; Glucose; Edible oil; Metabolism; Fish oil; Central nervous system; Encephalon
• ISSN: 0952-3278; 1532-2823
• DOI: 10.1016/j.plefa.2011.04.008

Abstract Cerebral metabolic rate of glucose (CMRg) is lower in individuals affected by cognitive decline and dementia, especially in Alzheimer's disease. However, as yet there is no consensus as to whether CMRg decreases during healthy aging. Epidemiological studies show that weekly consumption of fish abundant in ω3 fatty acids has a protective effect on cognition during aging. Thus, the primary objective of this human study was to use positron emission tomography analysis with18 F-fluorodeoxyglucose to evaluate whether supplementation with a fish oil rich in ω3 fatty acids increases cerebral glucose metabolism in young or elderly adults. Healthy young (23±5 y old; n =5) and elderly (76±3 y old; n =6) women and men were included in the study. Semi-quantitative expression of the data as ‘standardized uptake values’ showed that elderly participants had significantly lower cerebral glucose metabolism compared with the young group. However, when expressed quantitatively a CMRg, there was no effect of age or ω3 supplementation on glucose metabolism in any of the brains regions studied. Higher plasma triglyceride levels and higher plasma insulin levels were associated with lower CMRg in several regions, suggesting that a trend towards the metabolic syndrome may be associated with cerebral hypometabolism. We conclude that under these experimental conditions, ω3 supplementation did not affect brain glucose metabolism in the healthy elderly. Future studies in this area should address whether glucose intolerance or other conditions linked to the metabolic syndrome impact negatively on brain glucose metabolism and cognition.