Protopine Explained

Protopine is an alkaloid occurring in opium poppy,^[1] Corydalis tubers^[2] and other plants of the family papaveraceae, like Fumaria officinalis.^[3] Protopine is metabolically derived from the benzylisoquinoline alkaloid (S)-Reticuline through a progressive series of five enzymatic transformations: 1) berberine bridge enzyme to (S)-Scoulerine; 2) (S)-cheilanthifoline synthase/CYP719A25 to (S)-Cheilanthifoline; 3)  (S)-stylopine synthase/CYP719A20 to (S)-Stylopine; 4) (S)-tetrahydroprotoberberine N-methyltransferase to (S)-cis-N-Methylstylopine; and ultimately, 5) N-methylstylopine hydroxylase to protopine.^[4]

It has been found to inhibit histamine H1 receptors and platelet aggregation, and acts as an analgesic.^[5]

See also

• Protopine 6-monooxygenase
• Cryptopine
• Bürgi-Dunitz angle

Notes and References

1. http://www.thefreedictionary.com/Protopine The Free Dictionary: Protopine
2. 10.1016/j.ejphar.2004.11.004. 15588728. 2004. Jiang. B. Cao. K. Wang. R. Inhibitory effect of protopine on K(ATP) channel subunits expressed in HEK-293 cells.. 506. 2. 93–100. European Journal of Pharmacology.
3. Vrba . J. . Vrublova . E. . Modriansky . M. . Ulrichova . J. . Protopine and allocryptopine increase mRNA levels of cytochromes P450 1A in human hepatocytes and HepG2 cells independently of AhR . 10.1016/j.toxlet.2011.03.015 . Toxicology Letters . 203 . 2 . 135–141 . 2011 . 21419197 .
4. Hagel. Jillian M. Morris. Jeremy S. Lee. Eun-Jeong. Desgagne-Penix. Isabel. Bross. Crystal D. Chang. Limei. Chen. Xue. Farrow. Scott C. Zhang. Ye. 2015. Transcriptome analysis of 20 taxonomically related benzylisoquinoline alkaloid-producing plants. BMC Plant Biology. 15. 227. 10.1186/s12870-015-0596-0. 4575454 . 26384972. free.
5. 9368908. 1997. Saeed. SA. Gilani. Majoo. Shah. Anti-thrombotic and anti-inflammatory activities of protopine.. 36. 1. 1–7. 10.1006/phrs.1997.0195. Pharmacological Research. AH. RU. BH.