Astaxanthin modulates age-associated mitochondrial dysfunction in healthy dogs.

Area of Science:

• Gerontology
• Mitochondrial Biology
• Nutritional Science

Background:

• Aging is associated with mitochondrial dysfunction and increased oxidative stress.
• Mitochondrial health is crucial for cellular function and overall healthspan.
• Astaxanthin is a potent antioxidant with potential health benefits.

Purpose of the Study:

• To investigate the effects of dietary astaxanthin on mitochondrial function in young and geriatric dogs.
• To assess astaxanthin's impact on oxidative stress markers in canine blood.
• To determine if astaxanthin can modulate age-related changes in mitochondrial parameters.

Main Methods:

• Feeding young and geriatric healthy female Beagle dogs (n=14/group) 0 or 20 mg astaxanthin daily for 16 weeks.
• Assessing mitochondrial function (membrane permeability, ATP production, enzyme activities, and number) in leukocytes.
• Measuring plasma markers of astaxanthin uptake, oxidative stress (glutathione, superoxide dismutase, nitric oxide, 8-hydroxy-2'-deoxyguanosine, 8-isoprostane, protein carbonyl).

Main Results:

• Aging increased complex III cytochrome c oxidoreductase but decreased 8-hydroxy-2'-deoxyguanosine and protein carbonyl.
• Mitochondrial function improved in both age groups, with greater gains in geriatric dogs (increased ATP production, mitochondria mass, cytochrome c oxidoreductase activity).
• Astaxanthin increased the reduced glutathione to oxidized glutathione ratio in young dogs and decreased nitric oxide in both groups.

Conclusions:

• Dietary astaxanthin supplementation enhances mitochondrial function in canine leukocytes.
• Astaxanthin's benefits appear most pronounced in geriatric dogs, suggesting a role in mitigating age-related decline.
• Astaxanthin likely improves mitochondrial function by reducing oxidative damage to cellular DNA and proteins.