Good guys from a shady family

Norharmane prevents muscle aging via activation of SKN-1/NRF2 stress response pathways

Sarcopenia, the age-related decline in muscle mass and function, is a significant contributor to increased frailty and mortality in the elderly. Currently, no FDA-approved treatment exists for sarcopenia. Here, we identified norharmane (NR), a β-carboline alkaloid, as a potential therapeutic agent for mitigating muscle aging. We aimed to determine the ability of NR to delay muscle aging in Caenorhabditis elegans (C. elegans), mouse, and muscle cells in mice and humans. NR treatment improved swimming ability and increased the maximum velocity in aged C. elegans. Transcriptomic analysis revealed that NR upregulated detoxification genes in C. elegans, including cytochrome P450, UGT, and GST enzymes. NR-induced benefits were dependent on the SKN-1/Nrf2 stress response pathway. In mammalian models, NR delayed cellular senescence in human skeletal muscle myoblasts and enhanced myogenesis in C2C12 cells and primary aged myoblasts. NR supplementation in aged mice prevented muscle loss, improved muscle function, and reduced markers of cellular senescence. We found that the p38 MAPK pathway mediated NR activation of Nrf2 by disrupting the Nrf2-Keap1 interaction. NR also improved oxygen consumption rates and promoted mitochondrial biogenesis. These findings suggest that NR is a promising candidate for preventing sarcopenia and improving muscle health.

Brain foods - the role of diet in brain performance and health

The performance of the human brain is based on an interplay between the inherited genotype and external environmental factors, including diet. Food and nutrition, essential in maintenance of brain performance, also aid in prevention and treatment of mental disorders. Both the overall composition of the human diet and specific dietary components have been shown to have an impact on brain function in various experimental models and epidemiological studies. This narrative review provides an overview of the role of diet in 5 key areas of brain function related to mental health and performance, including: (1) brain development, (2) signaling networks and neurotransmitters in the brain, (3) cognition and memory, (4) the balance between protein formation and degradation, and (5) deteriorative effects due to chronic inflammatory processes. Finally, the role of diet in epigenetic regulation of brain physiology is discussed.