Spermidine is a polyamine with the chemical formula: C7H19N3. it is found in ribosomes and living tissues and has various metabolic functions in living organisms.
Dietary sources
There are many dietary sources of spermidine, including grapefruit, soy products, beans, corn, whole grains, chickpeas, peas, peppers, broccoli, oranges, green tea, rice bran, and fresh green peppers.
It can also be found in shiitake mushrooms, amaranth seed kernels, wheat germ, cauliflower, broccoli, and a variety of ripened cheeses and durians.
It is worth noting that most of the foods in the Mediterranean diet are rich in spermidine. This at least explains the phenomenon of the "blue zone" and why people there usually live longer than elsewhere.
Effects
Spermidine plays a vital role in living organisms such as humans and even in plants. One of spermine's biggest and most influential roles is its ability to fight aging and promote autophagy. This function is also where other functions originate.
Spermidine synchronises a number of biological processes (such as Ca2 , Na , K -ATPase), as well as maintaining membrane potential and controlling the ph and volume of cells. Processes regulated by spermidine, such as Ca2 , are brought together by the glutamatergic N-methyl-d-aspartate receptor (NMDA receptor). This receptor is associated with nitric oxide synthase, cGMP/PKG activation pathway, and reduction of Na ,K -ATPase activity at cortical synapses.
Spermidine is long-lived, due to its great influence on the chromogenic value-mediated regulation of gene expression, yet its mechanisms are not fully understood. Spermidine synthase catalyses the formation of spermidine. Spermidine, in turn, can further synthesise polyamines, an ability that encompasses thermal spermidine. This ability to synthesise polyamines, including thermo spermine, can help to adapt to dry weather as well as salinity.
Spermidine also regulates plant growth, helps transcribe RNA in the test tube, and inhibits NOS. Spermidine is also a precursor to polyamines, like spermine and thermospermine. These polyamines help regulate plant adaptation to dry climates as well as salinity.
Spermidine has been tested and found to promote hair lengthening and elongation. Spermidine has also been found to enhance the performance of the epithelial stem cell-associated keratins K15 and K19; dosage-regulated activity of the K15 promoter in situ; colony-forming efficiency; multiplication; and performance of isolated human K15-GFP cells in vitro.
Spermidine is synthesised from putrescine and is also a precursor of spermine.
