Melatonin plus physical exercise are highly neuroprotective in the 3xTg-AD mouse

Area of Science:

• Neuroscience
• Gerontology
• Pharmacology

Background:

• Alzheimer's disease (AD) is a progressive neurodegenerative disorder with no effective treatments.
• Investigating lifestyle interventions and pharmacological agents is crucial for managing AD.
• Current therapeutic strategies for AD are limited, necessitating research into novel approaches.

Purpose of the Study:

• To evaluate the neuroprotective potential of physical exercise and melatonin in a mouse model of Alzheimer's disease.
• To assess the individual and combined effects of these interventions on AD pathology and cognitive function.
• To explore the impact of exercise and melatonin on key Alzheimer's disease hallmarks, including amyloid-beta, tau, oxidative stress, and mitochondrial dysfunction.

Main Methods:

• Assay of physical exercise and melatonin in 3xTg-AD male mice (6-12 months old).
• Behavioral analysis to assess cognitive impairment and psychological symptoms.
• Brain tissue analysis to quantify amyloid-beta oligomers, hyperphosphorylated tau, oxidative stress markers, and mitochondrial integrity.

Main Results:

• Both physical exercise and melatonin reduced soluble amyloid-beta oligomers.
• Melatonin alone decreased hyperphosphorylated tau and counteracted immunosenescence.
• Physical exercise ameliorated anxiety, exploration deficits, and emotionality.
• Both interventions protected against cognitive decline, oxidative stress, and mitochondrial DNA reduction.
• Combined treatment was uniquely effective in preventing the decrease of mitochondrial complexes.

Conclusions:

• Physical exercise and melatonin offer distinct but complementary neuroprotective benefits in Alzheimer's disease.
• The combination of melatonin and physical exercise may provide synergistic effects against multiple AD-related pathologies.
• Further research into combined interventions could lead to novel therapeutic strategies for Alzheimer's disease.