Ergot alkaloids are naturally occurring active ingredients found primarily in the ergot fungus (Claviceps purpurea). They are used as an isolated component in various medicinal products because of their psychotropic and labor- and circulation-promoting properties.
What are ergot alkaloids?
The parasitic crescent-shaped cereal fungus grows mainly in grain ears after infection of the grain. Because alkaloids have high toxicity as a secondary plant metabolite, various strategies are used in agriculture to prevent infestation. Until the 20th century, there were regular mass poisonings caused by the consumption of contaminated grain, which was referred to as “ergotism”. Today, the term is used to refer to the side effects that occur with chronic ingestion of ergotamine. In structure, ergot alkaloids consist of ergoline, a nitrogenous organic chemical compound whose abstracted substances are used in the treatment of migraine, hypotension, Parkinson’s disease, and cardiovascular disease. Lysergic acid is extracted from the ergot mushroom, which is used to produce LSD (lysergic acid diethylamide). For this reason, the release of the drug ergotamine is restricted by the German Basic Substances Control Act. Even in low concentrations, the alkaloids of ergot have a toxic effect and influence the central nervous system. Currently, the alkaloids and derivatives of the cereal parasite are being discussed as neuro-psychotropic drugs. In pharmacological parlance, “dirty drugs” are drugs that bind to various receptors in the brain. On the one hand, this leads to a broad spectrum of effects, but is also often accompanied by unpredictable side effects. Science is working to move closer to a more targeted effect. In addition to ergot alkaloids, British biochemist Henry Hallett Dale was able to detect histamine as a natural substance in ergot.
Pharmacological action
Ergot alkaloids act in a variety of ways in the body. Primarily, they are referred to as dopamine agonists. That is, they stimulate dopamine receptors, thereby intensifying dopamine action in the body. They directly interfere with the autonomic nervous system, which coordinates our body and organ functions. This effect is used, for example, in Parkinson’s disease, since the disease is triggered primarily by a lack of dopamine. Individual ergot alkaloids can cause neurological disorders and affect the central nervous system even at low concentrations. This can result in epileptic seizures or convulsions. Other alkaloids contain a toxicant that can cause limb death by blocking blood vessels. Five to ten percent of ergot can already cause death in an adult human. The composition of the various ergot alkaloids and their high concentration is responsible for this. The active substances can both block and excite the receptors on the blood vessels. Depending on which alkaloid is involved. The successful treatment of migraine is explained by the effect on the blood vessels. Binding of the substances to the alpha receptors of the muscles also triggers contraction of the uterus. One ergot alkaloid that is used is ergometrine. It is a uterotonic (has a tonic effect on the uterus) that has an alpha-sympatholytic effect (cancels the effects of the sympathetic nervous system) and has a direct stimulatory effect on vascular smooth muscle and the uterus. In the venous system, ergotamine in its natural form has a pronounced vasoconstrictor (constricting) effect on venous and arterial vessels. In addition, a serotoninergic (responding to or containing serotonin) effect is discussed. Ergotamine derivatives are detectable in breast milk. They can induce vomiting, diarrhea, and hypertension in the breastfed infant. Lysergic acid dilates pupils and increases blood pressure, may induce perceptual changes in sense of time and in visual and auditory stimuli. LSD is a mood-altering hallucinogen. Furthermore, some derivatives of ergot alkaloids find use. Bromocriptine and cabergoline, for example, have dopaminergic properties and inhibit the release of the hormone prolactin. Dihydroergotamine has blood pressure and vasoregulatory effects. Dihydroergocryptin acts selectively on D2 receptors.Dihydroergotoxin, in turn, can positively influence brain performance in combination with other preparations and is antihypertensive. Lisuride and pergolide bind to dopamine and serotonin receptors. Methylergometrine has a contractile (tonic) effect on the uterus.
Medicinal use and application
In medicine, the substances of the fungus, despite their toxicity, represent a group of analeptics with high efficiency. Therefore, they are used in a wide variety of diseases. Dihydroergotamine in: Hypotension, Fainting attacks, Cardiovascular complaints, Acute migraine attacks with and without aura. Dihydroergotoxin in: Hypertension / senile hypertension, concomitant treatment of Raynaud’s syndrome, visual field disorders of vascular origin, symptomatic treatment for veno-lymphatic insufficiency, brain disorders, Alzheimer’s disease, dementia, migraine. Even small amounts can cause nausea and vomiting. The drug is therefore also used as an emetic. Ergotamine used for: Cluster headache, migraine. Dihydroergocryptine, lisuride, cabergoline, and pergolide for: Parkinson’s disease. Dihydroergocryptine in: Parkinson’s disease and interval treatment of migraine. Bromocriptine in: Restless Legs Syndrome, menstrual cycle disorders, female infertility, male hyperprolactinemia, prolactinomas, acromegaly, benign mammary gland disorders, and Parkinson’s disease. Cabergoline in turn in: Hyperprolactinemic disorders. Methylergometrine in: Promotions of placental abruption, treatments of uterine atony, and treatment of postpartum hemorrhage.
Risks and side effects
The following side effects may occur: Headache, vomiting, in long-term treatment, circulatory problems in the hands and feet up to vascular occlusion and death of the affected region, angina pectoris, gastrointestinal problems, loss of appetite, sleep disturbances, restlessness, stuffy nose, constipation, slowed heartbeat, Blood pressure drop, circulation problems, dizziness, itching, tingling, and numbness and cold feeling in arms and legs, anxiety, depression, skin reactions, muscle weakness, muscle pain, muscle cramps, heart rate too slow or too fast (bradycardia, tachycardia), heart valve damage, Heart attack, heart palpitations, respiratory disorders, edema, fibrosis, dyskinesias, hallucinations, hypotension, drowsiness, sweating, dry mouth, stomach pain, stomach cramps, feeling weak, heartburn, water retention in tissues, weight change, restlessness, loss of libido, tremors, ringing in ears, Nightmares, delusions, upper abdominal discomfort, digestive weakness, painful legs, hair loss, visual disturbances, psychosis, nervousness, incoordination, incontinence, frequent urination, facial pallor, stroke, uterine contraction pain, hypogalactia, and behavioral disturbances. Side effects common to all dopamine agonists include libido increase and hypersexuality, binge eating, obsessive-compulsive disorder, and decreased impulse control.
