NOX activity in brain aging: exacerbation by high fat diet

Area of Science:

• Neuroscience
• Aging Research
• Nutritional Science

Background:

• NADPH oxidase (NOX) is implicated in cellular signaling and oxidative stress.
• Age-related changes in the brain can impact susceptibility to dietary factors.
• High-fat diets are known to influence metabolic and inflammatory processes.

Purpose of the Study:

• To investigate the combined effects of aging and high-fat diet on NADPH oxidase (NOX) activity and expression in the brain.
• To determine if age influences the brain's response to dietary fat intake.
• To assess the impact on oxidative stress markers and neuroinflammation.

Main Methods:

• Evaluation of NOX activity and subunit expression in the frontal cerebral cortex of mice at different ages (7, 16, 24 months).
• Mice were fed either a Western diet (WD) or a very high-fat lard diet (VHFD) for 4 months.
• Quantification of protein carbonyls (oxidative stress marker) and assessment of microgliosis and astrocytosis.

Main Results:

• NOX activity was significantly affected by age, with increases observed only in aged mice fed a very high-fat diet (VHFD).
• NOX subunit expression and protein oxidation were elevated by diet, but only in aged mice.
• Neuronal localization of NOX subunits and protein carbonylation was observed.
• Reactive microgliosis mirrored diet-induced NOX activation and oxidation, unlike astrocytosis.

Conclusions:

• Both aging and dietary fat intake contribute to NOX activation in the brain.
• Aged mice exhibit increased sensitivity to the detrimental effects of high-fat diets on the brain.
• High-fat diets may worsen age-related oxidative stress in the brain through enhanced NOX activity.