Several alkaloids that function as monoamine oxidase inhibitors (MAOIs) are found in the seeds of Peganum harmala (also known as Harmal or Syrian Rue), including harmine, harmaline, and harmalol, which are members of a group of substances with a similar chemical structure collectively known as harmala alkaloids. These alkaloids are of interest for their use in Amazonian shamanism, where they are derived from other plants. The harmala alkaloid harmine which was once known as Telepathine and Banisterine is a naturally occurring beta-carboline alkaloid that is structurally related to harmaline, and also found in the vine Banisteriopsis caapi. Tetrahydroharmine is also found in B. caapi and P. harmala. Dr. Alexander Shulgin has suggested that harmine may be a breakdown product of harmaline [1]. Harmine and harmaline are reversible MAOIs of the MAO-A isoform of the enzyme, and can stimulate the central nervous system by inhibiting the metabolism of monoamine compounds such as serotonin and norepinephrine.
The harmala alkaloids occur in Peganum harmala in concentrations of roughly 3%, though tests have documented anywhere from 2-7% or even higher,[1] as natural sources tend to vary widely in chemical makeup. Harmala alkaloids are also found in the Banisteriopsis caapi vine, the key plant ingredient in the sacramental beverage Ayahuasca, in concentrations that range between 0.31-8.43% for harmine, 0.03-0.83% for harmaline and 0.05-2.94% for tetrahydroharmine.[2] Other psychoactive plants are often added to Ayahuasca to achieve visionary states of consciousness; for example leaves from Psychotria viridis, which is a source of dimethyltryptamine (DMT). The harmala alkaloids serve to potentiate these brewed compounds by preventing their breakdown in the digestive tract. The harmala alkaloids are not especially psychoactive on their own, even at high dosages, when vomiting and diarrhea become the main effect.
Harmala alkaloids are also found in many other plants, such as tobacco and passion flower.
Contents |
Telepathine was originally thought to be the active chemical constituent of Banisteriopsis caapi, a key plant ingredient in the preparation of Ayahuasca; a sacramental beverage from the Amazon. This isolated chemical was so named because of the reported effects of Ayahuasca among the indigenous users, including: collective contact with and/or visions of jaguars, snakes, and jeweled birds, and ancestral spirits; the ability to see future events; and as the name suggests, telepathic communication among tribal members. It was assumed to be a newly discovered chemical at the time, however, it was soon realized that Telepathine was already more widely known as "harmine" from its previous discovery in Peganum harmala (Syrian Rue).
As mentioned above, some harmala alkaloids can be used as an MAOI (MonoAmine Oxidase Inhibitor) to facilitate the ingestion of DMT and other tryptamines; while not generally used as a hallucinogen alone, there are reports of such use.[3] In high doses, it acts as purgative. Harmala alkaloids from Banisteriopsis caapi have been used to treat Parkinson's disease. As a benzodiazepine site inverse agonist, harmala alkaloids are used as a model for Essential Tremor (ET) when injected to animals. Rats being treated with harmaline exhibit severe tremors after 5–7 minutes. Individuals diagnosed with Essential Tremor have been found to have elevated blood levels of harmala alkaloids.[4]
It is important to note that unlike many synthetic pharmaceutical MAOIs such as phenelzine, harmine is reversible and selective meaning it does not have nearly as high a risk for the "cheese syndrome" caused by consuming tyramine-containing foods, which is a risk associated with monoamine oxidase A inhibitors, but not monoamine oxidase B inhibitors.[5]
"Harmine showed cytotoxicity against HL60 and K562 cell lines. This could explain the cytotoxic effect of P. harmala on these cells."[6]
Norharmane, exerts neuroprotective properties by suppressing kynurenine neurotoxic metabolites such as quinolinic acid, 3OH-kynurenine and nitric oxide synthase.[7]
Harmine is a reversible inhibitor of MAO-A (RIMA).
Harmaline is a reversible inhibitor of MAO-A (RIMA).[8]
|
|