|Jmol-3D images||Image 1|
|Molar mass||145.25 g mol−1|
|Density||925 mg mL−1|
22-25 °C, 295-298 K, 72-77 °F
|Solubility in water||145 g L−1 (at 20 °C)|
|Refractive index (nD)||1.479|
|GHS signal word||DANGER|
|GHS hazard statements||H314|
|GHS precautionary statements||P280, P305+351+338, P310|
|Flash point||112 °C|
| (what is: / ?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
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. (4) Polyamines, such as spermidine, are polycationic aliphatic amines (present at high concentrations in the hippocampus) and are multifunctional.(1) They serve vital roles in cell survival. Spermidine synchronizes an array of biological processes such as Ca2+, Na+, K+ -ATPase. Na+, K+-ATPase determines Na+ and K+ gradients across the plasma membranes of cells that use membrane potentials and by this means maintains membrane potential and controls 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. Even with this information, spermidine in normal human tissue physiology still remains poorly understood. Spermidine synthase (SPDS) catalyzes the formation of spermidine. Spermidine helps further polyamines, this can include polyamines and thermospermine. Tese contribute to a resistance of dry climate and salinity. (1) Within plants it is known to regulate plant growth, assisting the in vitro process of transcribing RNA, and inhibition of NOS. Also, spermidine is a precursor to further polyamines, such as spermine and thermospermine, most of which contribute to tolerance against drought and salinity in plants. (3) Spermidine has been tested and discovered to encourage hair shaft elongation and lengthen hair growth. Spermidine has also been found to “upregulate expression of the epithelial stem cellassociated keratins K15 and K19, and dose-dependently modulated K15 promoter activity in situ and the colony forming efficiency, proliferation and K15 expression of isolated human K15-GFP+ cells in vitro.” (2) Spermidine interacts with anionic domains of macromolecules. (2) Spermidine is a polycationic polyamine involved in cellular metabolism. Spermine is synthesized from putrescine and is a precursor of spermine.
Spermine's known actions include:
- Inhibition of neuronal nitric oxide synthase, nNOS
- Assisting the in vitro process of transcribing RNA via stimulation of T4 polynucleotide kinase and T7 RNA polymerase activity; it binds to and precipitates DNA and is utilized in purifying DNA-binding proteins
- Regulation and promotion of plant growth - as a polyamine plant growth regulator it is also a plant hormone-promoting somatic embryogenesis.
Biochemical actions 
- Inhibits neuronal nitric oxide synthase (nNOS)
- Binds and precipitates DNA
- May be used for purification of DNA-binding proteins
- Stimulates T4 polynucleotide kinase and T7 RNA polymerase activity
- Polyamine plant growth regulator
Some of the uses 
- Spermidine can be used in electroporation while transferring the DNA into the cell under the electrical impulse.
- Stimulating autophagy. Recently Tirupathi Pichiah et al., suggested that spermidine may be helpful for treating type 2 diabetes.
See also 
- Hu, J; Mahmoud, MI; El-Fakahany, EE (1994). "Polyamines inhibit nitric oxide synthase in rat cerebellum". Neuroscience letters 175 (1–2): 41–5. doi:10.1016/0304-3940(94)91073-1. PMID 7526294.
- Wan, CY; Wilkins, TA (1993). "Spermidine facilitates PCR amplification of target DNA". PCR methods and applications 3 (3): 208–10. PMID 8118404.
- Cull, M; McHenry, CS (1990). "Preparation of extracts from prokaryotes". Methods in enzymology. Methods in Enzymology 182: 147–53. doi:10.1016/0076-6879(90)82014-S. ISBN 978-0-12-182083-1. PMID 2107372.
- Blethen, SL; Boeker, EA; Snell, EE (1968). "Argenine decarboxylase from Escherichia coli. I. Purification and specificity for substrates and coenzyme". The Journal of Biological Chemistry 243 (8): 1671–7. PMID 4870599.
- Wu, WH; Morris, DR (1973). "Biosynthetic arginine decarboxylase from Escherichia coli. Subunit interactions and the role of magnesium ion". The Journal of Biological Chemistry 248 (5): 1696–9. PMID 4571774.
- Tabor, CW; Tabor, H (1984). "Polyamines". Annual review of biochemistry 53: 749–90. doi:10.1146/annurev.bi.53.070184.003533. PMID 6206782.
- Krug, MS; Berger, SL (1987). "First-strand cDNA synthesis primed with oligo(dT)". Methods in enzymology. Methods in Enzymology 152: 316–25. doi:10.1016/0076-6879(87)52036-5. ISBN 978-0-12-182053-4. PMID 2443800.
- Karkas, JD; Margulies, L; Chargaff, E (1975). "A DNA polymerase from embryos of Drosophila melanogaster. Purification and properties". The Journal of Biological Chemistry 250 (22): 8657–63. PMID 241752.
- Bouché, JP (1981). "The effect of spermidine on endonuclease inhibition by agarose contaminants". Analytical Biochemistry 115 (1): 42–5. doi:10.1016/0003-2697(81)90519-4. PMID 6272602.
- Tobias Eisenberg, Heide Knauer, Alexandra Schauer, Sabrina Büttner, Christoph Ruckenstuhl, Didac Carmona-Gutierrez, Julia Ring, Sabrina Schroeder, Christoph Magnes, Lucia Antonacci, Heike Fussi, Luiza Deszcz, Regina Hart, Elisabeth Schraml, Alfredo Criollo, Evgenia Megalou, Daniela Weiskopf, Peter Laun, Gino Heeren, Michael Breitenbach, Beatrix Grubeck-Loebenstein, Eva Herker, Birthe Fahrenkrog, Kai-Uwe Fröhlich, Frank Sinner, Nektarios Tavernarakis, Nadege Minois, Guido Kroemer, Frank Madeo (4 October 2009). "Induction of autophagy by spermidine promotes longevity,". Nature Cell Biology 11 (11): 1305–14. doi:10.1038/ncb1975. PMID 19801973.
- Leeuwenhoek, A. van (1678) Observationes D. Anthonii Leeuwenhoek, de natis e semine genitali animalculis. Letter dated November 1677. Philos. Trans. Roy. Soc. London, 12, 1040-1043.
- Eisenberg, Tobias; Knauer, Heide; Schauer, Alexandra; Büttner, Sabrina; Ruckenstuhl, Christoph; Carmona-Gutierrez, Didac; Ring, Julia; Schroeder, Sabrina et al. (2009). "Induction of autophagy by spermidine promotes longevity". Nature Cell Biology 11 (11): 1305–14. doi:10.1038/ncb1975. PMID 19801973.
- Tirupathi Pichiah, PB; Suriyakalaa, U, Kamalakkannan, S, Kokilavani, P, Kalaiselvi, S, SankarGanesh, D, Gowri, J, Archunan, G, Cha, YS, Achiraman, S (2011 Oct). "Spermidine may decrease ER stress in pancreatic beta cells and may reduce apoptosis via activating AMPK dependent autophagy pathway". Medical hypotheses 77 (4): 677–9. doi:10.1016/j.mehy.2011.07.014. PMID 21831529.