Snowdrop

Galanthamine (23) is an alkaloid extracted from the common snowdrop Galanthus nivalis. This compound is a long-acting, competitive AChE inhibitor which appears to be somewhat more specific for acetylcholinesterase than plasma butyrylcholinesterase (132). It is well tolerated during long-term treatment (133) and is being evaluated clinically for AD (134). 

Schnee-flocke, /, snowflake. gips, m. snowy (foliated) gypsum, -glockcben, n. snowdrop, -grenze, /, snow line, -webe, /. snowdrift. schneeweisB, a. snow-white. 

SUDHAKAR D, FU X, SSTOGER E, WILLIAMS S, SPENCE J, BROWN D P, BHARATHI M, GATEHOUSE J A, CHRISTOU p (1998) Expression and immunolocalisation of the snowdrop Ictin, GNA in transgenic rice plants. Transgenic Res. 7 371-8... 

Bulbs are normally planted when dormant, as dry bulbs. For spring displays, bulbs must be put in the ground in fall summer- and fallflowering bulbs are planted in spring. Only the very small bulbs such as snowdrops and winter aconites are usually planted while in leaf, just after flowering, as they can easily dry out. If you have to plant them as dry bulbs, soak them for 24 hours in lukewarm water prior to planting. 

Traditionally, plants are a rich source of AChE inhibitors. People from the Caucasus used bulbs of snowdrops Galanthus sp.) to treat forgetfulness [25]. The active compound in this plant has been isolated and called galanthamine. Other plant-derived AChE inhibitors used for treatment of Alzheimer s disease include Huperzine A from Huperzia serrata and Rivastigmine (Excelon). The latter is a derivative from physostigmine isolated from the calabar bean, Physos-tigma vmmosum. 

M. Heinrich, H. L. Teoh Galanth-amine from snowdrop — the development of a modem dmg against Alzheimer s disease from local Caucasian knowledge. J Ethno-pharmacol 2004, 92, 147—162. 

Galanthamine (10) Galanthus woronowii Losinsk (snowdrop) Anti-Alzheimer s disease... 

Heinrich M, Teoh HL, Galanthamine from snowdrop- the development of a modern drug against Alzheimer s disease from local Gaucasian knowledge, /Ethnopharmacol92 A7— 62, 2004. 

Origin Synthetic compound Synthetic compound Natural product (from the flower snowdrop)... 

FIGURE 12-29. Icon for the cholinesterase inhibitor galanthamine. This agent is naturally present in snowdrops and daffodils and may also have nicotinic agonist or cholinergic-releasing actions as well as cholinesterase actions. It is also in testing for Alzheimer s disease. 

Galanthamine is a very interesting cholinesterase inhibitor found in snowdrops and daffodils. It may have a dual mechanism of action, matching cholinesterase inhibition with direct nicotinic agonist actions causing acetylcholine release (Fig. 12—29). Early testing in Alzheimer s disease is underway. 

Galantamine, unlike the other anticholinesterases in clinical use, is derived from the alkaloids from the daffodil and snowdrop family. It is a reversible, competitive inhibitor of acetylcholinesterase with some inhibitory action on butyryl cholinesterase. It is also an agonist at nicotinic receptor sites. Although a clinically effective drug, galantamine frequently causes gastrointestinal side effects. 

Down, R.E., Gatehouse, A.M.R., Hamilton, W.D.O., and Gatehouse, J.A., Snowdrop lectin inhibits development and decreases fecundity of the glasshouse potato aphid (Aulacorthum solani) when administered in vivo and via transgenic plants both in laboratory and glasshouse trials, J. Insect Physiol., 42, 1035-1045, 1996. 

Hogervorst, P.A.M., Ferry, N., Gatehouse, A.M.R., Wackers, F.L., and Romeis, J., Direct effects of snowdrop lectin (GNA) on larvae of three aphid predators and fate of GNA after ingestion, J. Insect Physiol., 52, 614-624, 2006. 

Van Damme, E.J.M., Allen, A.K., and Peumans, W.J., Isolation and characterization of a lectin with exclusive specificity towards mannose from snowdrop (Galanthus nivalis) bulbs, FEBS Lett., 215, 140-144, 1987. 

Shibuya, N., Berry, J. E., and Glodstein, I. J., (1988). One-step purification of murine IgM and human a2-macroglobulin by affinity chromatography on immobilized snowdrop bulb lectin. Arch. Biochem. Biophys. 267, 676-680. 

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