Extra virgin olive oil improves learning and memory in SAMP8 mice.

Area of Science:

• Neuroscience
• Nutrition Science
• Biochemistry

Background:

• Antioxidants, particularly polyphenols in extra virgin olive oil (EVOO), show potential in reversing age- and disease-related cognitive deficits.
• Aging and certain diseases are associated with cognitive impairment, increased amyloid-beta protein, and oxidative stress in the brain.

Purpose of the Study:

• To investigate the effects of EVOO on learning and memory in SAMP8 mice, a model of age-related cognitive decline.
• To explore the role of brain oxidative stress and antioxidant mechanisms in mediating these effects.

Main Methods:

• Eleven-month-old SAMP8 mice were fed EVOO, coconut oil, or butter for six weeks.
• Cognitive function was assessed using T-maze foot shock avoidance and one-trial novel object recognition tests.
• Brain tissue analysis measured oxidative stress markers (glutathione, glutathione reductase, superoxide dismutase, 4-hydroxynoneal, 3-nitrotyrosine).

Main Results:

• EVOO consumption significantly improved learning acquisition in the T-maze and recognition memory in the novel object recognition test compared to control diets.
• EVOO enhanced T-maze retention compared to butter.
• EVOO administration led to increased brain glutathione levels, glutathione reductase and superoxide dismutase activity, and decreased levels of 4-hydroxynoneal and 3-nitrotyrosine, indicating reduced oxidative stress.
• These beneficial effects were dose-dependent and amplified with higher polyphenol concentrations in EVOO.

Conclusions:

• EVOO ameliorates age- and disease-related learning and memory deficits in SAMP8 mice.
• The cognitive benefits are associated with the reversal of brain oxidative damage, mediated by EVOO's antioxidant properties.
• Higher polyphenol content in EVOO enhances its neuroprotective effects on cognitive function.