Cytisine, also known as baptitoxine, cytisinicline, or sophorine, is an

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...

that occurs naturally in several plant genera, such as ''

Laburnum ''Laburnum'', sometimes called golden chain or golden rain, is a genus of two species of small trees in the subfamily Faboideae of the pea family Fabaceae. The species are '' Laburnum anagyroides''—common laburnum and '' Laburnum alpinum''� ...

'' and ''

Cytisus ''Cytisus'' is a genus of flowering plants in the family Fabaceae, native to open sites (typically scrub and heathland) in Europe, western Asia and North Africa. It belongs to the subfamily Faboideae, and is one of several genera in the tribe Ge ...

'' of the family Fabaceae. It has been used medically to help with

smoking cessation Smoking cessation, usually called quitting smoking or stopping smoking, is the process of discontinuing tobacco smoking. Tobacco smoke contains nicotine, which is addictive and can cause dependence. As a result, nicotine withdrawal often m ...

. Although widely used for smoking cessation in Eastern Europe, cytisine remains relatively unknown beyond it. However, it has been found effective in several randomized

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, diet ...

s, including some in the United States and a large one in New Zealand, and is being investigated in additional trials in the United States (being conducted by Achieve Life Sciences) and a non-inferiority trial in Australia in which it is being compared head-to-head with the smoking cessation aid varenicline (sold in the United States as Chantix). It has also been used entheogenically via mescalbeans by some Native American groups, historically in the

Rio Grande Valley The Lower Rio Grande Valley ( es, Valle del Río Grande), commonly known as the Rio Grande Valley or locally as the Valley or RGV, is a region spanning the border of Texas and Mexico located in a floodplain of the Rio Grande near its mouth. Th ...

predating even peyote.

Sources

Cytisine is extracted from the seeds of '' Cytisus laborinum'' L. (Golden Rain acacia), and is found in several genera of the subfamily

Faboideae The Faboideae are a subfamily of the flowering plant family Fabaceae or Leguminosae. An acceptable alternative name for the subfamily is Papilionoideae, or Papilionaceae when this group of plants is treated as a family. This subfamily is widely ...

of the family Fabaceae, including ''

'', '' Anagyris'', ''

Thermopsis ''Thermopsis'' is a genus of legumes, native to temperate North America and east Asia. They are herbaceous perennials and are known as goldenbanners or false-lupines. Species ''Thermopsis'' comprises the following species: * ''Thermopsis alpin ...

'', ''

Genista Genista is a genus of flowering plants in the legume family Fabaceae, native to open habitats such as moorland and pasture in Europe and western Asia. They include species commonly called broom, though the term may also refer to other genera, i ...

'', ''

Retama ''Retama'' (also known as ''rotem'', he, רותם) is a genus of flowering bushes in the legume family, Fabaceae. It belongs to the broom tribe, Genisteae. ''Retama'' broom bushes are found natively in North Africa, the Levant and some parts of ...

'' and ''

Sophora ''Sophora'' is a genus of about 45 species of small trees and shrubs in the pea family Fabaceae. The species have a pantropical distribution. The generic name is derived from ''sophera'', an Arabic name for a pea-flowered tree. The genus formerl ...

''. Cytisine is also present in ''

Gymnocladus ''Gymnocladus'' ( Neo-Latin, from Greek γυμνὀς, ''gymnos'', naked + κλάδος, ''klados'', branch) is a small genus of leguminous trees. The common name coffeetree is used for this genus. Description ''Gymnocladus'' species are very l ...

'' of the subfamily Caesalpinioideae.

Uses

Smoking cessation

Cytisine has been available in

post-Soviet states The post-Soviet states, also known as the former Soviet Union (FSU), the former Soviet Republics and in Russia as the near abroad (russian: links=no, ближнее зарубежье, blizhneye zarubezhye), are the 15 sovereign states that wer ...

for more than 40 years as an aid to smoking cessation under the brand name ''Tabex'' from the Bulgarian pharmaceutical company Sopharma AD. It was first marketed in Bulgaria in 1964 and then became widely available in the then-Soviet Union. In Poland, it is sold under the brand name ''Desmoxan'', and it is also available in Canada under the brand name ''Cravv''. Its molecular structure has some similarity to that of

nicotine Nicotine is a natural product, naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and ''Duboisia hopwoodii'') and is widely used recreational drug use, recreationally as a stimulant and anxiolytic. As ...

, and it has similar pharmacological effects. Like the smoking cessation aid varenicline, cytisine is a partial agonist of

nicotinic acetylcholine receptor Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic receptors also respond to drugs such as the agonist nicotine. They are found in the central and peripheral ner ...

s (nAChRs). Cytisine has a short

half-life Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable at ...

of 4.8 hours, As a result, the extract provides smokers with satisfaction similar to smoking a cigarette, alleviating the urge to smoke and reducing the severity of nicotine withdrawal symptoms, while also reducing the reward experience of any cigarettes smoked. Cytisine is rapidly eliminated from the body. In 2011, a randomized controlled trial with 740 patients found cytisine improved 12-month abstinence from nicotine from 2.4% with placebo to 8.4% with cytisine. A 2013

meta-analysis A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Meta-analyses can be performed when there are multiple scientific studies addressing the same question, with each individual study reporting me ...

of eight studies demonstrated that cytisine has similar effectiveness to varenicline but with substantially lower side effects. A 2014 systematic review and economic evaluation concluded that cytisine was more likely to be cost-effective for smoking cessation than varenicline.

Recreational

Plants containing cytisine, including the scotch broom and mescalbean, have also been used recreationally. Positive effects are reported to include a nicotine-like intoxication.

Reagent for organic chemistry

(−)-Cytisine extracted from ''Laburnum anagyroides'' seeds was used as a starting material for the preparation of "(+)- sparteine surrogate," for the preparation of enantiomerically enriched lithium anions of opposite stereochemistry to those anions obtained from sparteine.

Toxicity

Cytisine can interfere with breathing and cause death; i.v., in mice is about 2 mg/kg. Cytisine is also teratogenic. Māmane ('' Sophora chrysophylla'') can contain amounts of cytisine that are lethal to most animals. The

palila The palila (''Loxioides bailleui'') is a critically endangered finch-billed species of Hawaiian honeycreeper. It has a golden-yellow head and breast, with a light belly, gray back, and greenish wings and tail. The bird has a close ecological rel ...

(''Loxioides bailleui'', a

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...

), '' Uresiphita polygonalis virescens'' and ''

Cydia Cydia is a graphical user interface of APT (Advanced Package Tool) for iOS. It enables a user to find and install software not authorized by Apple on jailbroken iPhones, iPads and iPod Touch devices. It also refers to digital distribution pl ...

'' species (

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of w ...

s), and possibly

sheep Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to domesticated ...

and

goat The goat or domestic goat (''Capra hircus'') is a domesticated species of goat-antelope typically kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the a ...

s are not affected by the toxin for various reasons, and use māmane, or parts thereof, as food. ''U. p. virescens'' caterpillars are possibly able to sequester the cytisine to give themselves protection from getting eaten; they have

aposematic Aposematism is the advertising by an animal to potential predators that it is not worth attacking or eating. This unprofitability may consist of any defences which make the prey difficult to kill and eat, such as toxicity, venom, foul taste o ...

coloration which would warn off potential

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

References

External links

* {{Portal bar , Medicine Nicotinic agonists Alkaloids found in Fabaceae Lactams Bridged heterocyclic compounds Teratogens Plant toxins Nitrogen heterocycles Quinolizidine alkaloids Bulgarian inventions