DHA-enriched phospholipid diets modulate age-related alterations in rat hippocampus

Area of Science:

• Neuroscience
• Biochemistry
• Gerontology

Background:

• Aging in rats leads to decreased docosahexaenoic acid (DHA) in brain phospholipids like phosphatidylethanolamine (PE), plasmenylethanolamine (PmE), and phosphatidylserine (PS).
• This age-related decline in DHA may impact brain function, particularly cholinergic activity.

Purpose of the Study:

• To determine if dietary supplementation with DHA-enriched phospholipids can restore DHA levels in aged rats.
• To investigate the effects of such supplementation on cholinergic activity, specifically acetylcholine (Ach) release.

Main Methods:

• Male rats were fed standard diets until 18 months, then divided into groups receiving diets supplemented with DHA-enriched phospholipids from egg yolk (E-PL) or pig brain (B-PL) until 21 months.
• Phospholipid fatty acid composition and acetylcholine release (spontaneous and evoked) were analyzed and compared to a control group.

Main Results:

• The E-PL diet successfully restored polyunsaturated fatty acids (PUFAs), including DHA (22:6n-3), in PE and PmE compared to controls.
• E-PL supplementation also enhanced both spontaneous and evoked acetylcholine release.
• The B-PL diet did not restore PUFA levels but increased basal Ach levels in aged rats.

Conclusions:

• Dietary supplementation with DHA-enriched egg phospholipids is effective in correcting age-related PUFA deficits in rat brain phospholipids.
• This supplementation can enhance acetylcholine release, suggesting a potential therapeutic strategy for age-related cognitive decline.