An Update on Neuroaging on Earth and in Spaceflight.

Area of Science:

• Neuroscience
• Genetics
• Molecular Biology

Background:

• Brain aging involves complex, non-linear temporal processes.
• Epigenetic mechanisms, including non-coding RNAs, play a crucial role in neuroaging.
• Factors like genetics, oxidative stress, inflammation, lifestyle, and environmental exposures contribute to neuroaging.

Purpose of the Study:

• To review over 400 articles on the pathophysiology of brain aging, neuroaging, and neurodegeneration.
• To focus on the role of epigenetic mechanisms and non-coding RNAs, especially microRNAs, in gene regulation during aging.
• To identify candidate molecular biomarkers for neuroaging diagnostics and countermeasures.

Main Methods:

• Comprehensive literature review of over 400 articles.
• Focus on epigenetic mechanisms and non-coding RNAs, with emphasis on microRNAs.
• Analysis of factors influencing the rate of aging, including training and pharmacological interventions.

Main Results:

• Aging is a mosaic process with variable rates influenced by internal and external factors.
• MicroRNAs are pivotal in gene regulation, with their importance recognized by the 2024 Nobel Prize.
• Space environments can accelerate aging-like processes, highlighting environmental impacts.
• Numerous candidate molecular biomarkers for neuroaging require validation.

Conclusions:

• Epigenetic modifications and non-coding RNAs are central to understanding brain aging and neurodegeneration.
• Developing validated molecular biomarkers is essential for diagnosing and counteracting neuroaging.
• Interventions like cognitive and physical training can modulate aging rates.