Carnosine

Carnosine is a naturally occurring dipeptide (beta-alanine + L-histidine) found in high concentrations in skeletal muscle and brain tissue — long-lived, high-energy-demand tissues. It functions as an endogenous antioxidant, pH buffer, metal chelator, and anti-glycation agent. Carnosine has attracted significant interest in geroscience for its apparent ability to delay cellular senescence in human fibroblasts and extend lifespan in animal models.

Carnosine exerts its biological effects through multiple complementary pathways. As an antioxidant, it scavenges reactive oxygen and nitrogen species and inhibits lipid peroxidation. As a metal chelator, it sequesters pro-oxidant transition metal ions such as copper and zinc. As an anti-glycation agent, it reacts with reactive carbonyl compounds to prevent advanced glycation end product (AGE) formation. Carnosine also buffers intracellular pH during anaerobic exercise, protects mitochondrial function, and may upregulate stress protein expression and proteasomal activity to clear damaged proteins — a mechanism relevant to cellular aging.

Preclinical studies show carnosine suppresses cultured human fibroblast senescence and delays aging in senescence-accelerated mice and Drosophila. Animal studies confirm improved antioxidant status in liver, heart, and brain. Human studies primarily focus on exercise performance and carnosine's role as a pH buffer in muscle. Neurodegenerative disease applications are under active preclinical investigation as of 2025. Long-term human longevity data are lacking.

Peptides commonly paired with Carnosine for synergistic effects.