Spermidine (SMD)

Spermidine is a polyamine compound (C7H19N3) found in ribosomes and living tissues, and having various metabolic functions within organisms. It was originally isolated from semen. Spermidine synchronizes an array of biological processes (such as Ca2+, Na+, K+ -ATPase) thus maintaining membrane potential and controlling intracellular pH and volume. Spermidine regulates biological processes, such as Ca2+ influx by glutamatergic N-methyl-d-aspartate receptor (NMDA receptor), which has been associated with nitric oxide synthase (NOS) and cGMP/PKG pathway activation and a decrease of Na+,K+-ATPase activity in cerebral cortex synaptosomes. Spermidine is a longevity agent due to its impact on chromatin-mediated regulation of gene expression, however the mechanism is poorly understood. Spermidine synthase (SPDS) catalyzes the formation of spermidine.