St. John's Wort: Benefits, Reviews, Warnings?
Hypericum or St. John's Wort
Hypericum or St. John's wort or Scacciadiavoli (Hypericum perforatum) is a medicinal plant of the genus Hypericum.
It is a plant glabrous, with erect stem covered from two longitudinal stripes in relief.
Its leaves are speckled with tiny glands transparent backlit appear as holes (this feature is derived from the name perforatum) and essential oils that contain resin and colorless.
The flowers are a deep yellow with 5 petals and delicate, these are covered with dots blacks, which, when rubbed, fingers tinged red (due to the presence of a red pigment called hypericin).
The extract oily macerate is obtained from fresh flowering tops of the plant. It is used as a solvent sunflower oil.
Flavonoids, diantrachinoni (hypericin), tannins, proanthocyanidins, carotenoids and essential oils.
The properties are attributed to the hypericum plant complex characterized primarily by flavonoids and
one in particular, 'hypericin.
St. John's Wort, taken orally, is required for its antidepressant, antispasmodic, sedative and
antivirals, while the oil of St. John's wort, for topical use, it is useful as an emollient, healing, antiseptic,
anesthetic and in cases of dry skin caused by external agents (sun, wind) and sunburn.
After oral administration of an extract of Hypericum, the maximum blood concentration of hypericin is
reached in 2-2.6 hours. The half-life of hypericin is 24.8-26.5 hours.
In case of prolonged administration for 14 days (3 × 300 mg / day) the maximum blood concentration
is reached within 4 days. This prolonged action is probably due to the particular configuration
of the molecule of hypericin, which gives a good affinity for albumin and lipoproteins.
It is built on a structure of eight unsaturated rings symmetrical, fully aromatic.
MECHANISM OF ACTION:
The hypericin inhibits the enzyme monoamine oxidase (MAO), responsible for the deactivation of various mediators
central nervous system, has un'attinenza for GABA receptors and induces an arrest in the reuptake
serotonin, almost certainly, is the fundamental device antidepressant hypericum and is also the
neurotransmitter that regulates mood, with consequential increase of the outcomes related to the amount of serotonin usable.
Moreover also inhibits the enzyme catechol-O-methyltransferase (COMT), having the same effect.
St. John's Wort increases the nocturnal secretion of melatonin; also contains some tannins effect antidiarrotico
and some flavonoids diuretic effect.
Stimulates cell regeneration and this is in fact the reason for its effectiveness against burns.
Thanks to the emollient protects the skin giving it a quick feeling of well-being.
Used successfully in the case of: burns, joint pain, skin blemishes, psoriasis, dry
the skin of the face and body, aging skin, bed sores, stretch marks, scars, marks
caused by acne, chapped hands, hemorrhoids, insect bites, ulceration of the glans penis male rheumatism.
ESSENTIAL oil for external use, prevents infection of WOUNDS, flavonoids reduce inflammation
wounds of the same.
L 'ointment of St. John's wort reduces the healing time of burns, is anti-inflammatory, antiseptic and
The herb St. Giovannoi is inducer of several cytochrome P450 isoenzymes, including CYP2C9, CYP2D6, CYP3A4.
It seems that hyperforin binds to a receptor called the nuclear pregnane X receptor, causing
an increased expression of the gene encoding CYP3A4. This activity tends to increase the
availability of CYP3A4 with a consequent increase in the metabolism of drugs that are substrates.
When administered together with other CYP3A4 substrates, St. John's wort reduces the serum concentration and
The herb St. John's participates in the dangerous decrease in serum levels of cyclosporine in patients
syndrome transplanted from acute rejection of the organs neotrapiantati.
Even in this case, is called into question an increased metabolism for CYP3A4 induction, but there is also
alteration of a transporter, P-glycoprotein, which results in changes of the absorption and
Always through the induction of p-glycoprotein, St. John's wort can cause a decrease in serum levels
The St. John's wort also causes alterations in the menstrual cycle in women taking contraceptives
oral, although it is not reported any unwanted pregnancy. The induction of CYP3A4 metabolism increases
estradiol and all corticosteroids that are the substrate of this enzyme.
So you must carefully inform women who use this herb along with oral contraceptives,
that the contraceptive effect of the latter could be reduced, inviting them to use other methods
Carbamazepine is not affected by co-administration of St John's, although it is
also metabolized by CYP3A4, since the self-induction of CYP3A4 by the drug is greater than that
Breastfeeding (without professional supervision)
Were no interactions with other drugs metabolized by the microsomal P450 enzyme system,
as the plant is a strong inducer of CYP 3A4 enzyme that metabolizes 80% of marketed drugs,
some of the many warfarin, anticonvulsants and contraceptives.
It has interactions with:
immunosuppressive agents (cyclosporine)
decreases the anticoagulant effect of warfarin (Coumadin);
cardiac glycosides (digoxin) in the case of doses of hypericum exceeding 1 gram / day (dry weight),
inhibitors and non-nucleoside HIV reverse transcriptase inhibitors (nevirapine),
other protease inhibitors, reverse HIV (indinavir),
reduces the effect of oral contraceptives,
increases the effects of antidepressants: fluoxetine, paroxetine, Sertretalina.
It is not recommended for concomitant use with SSRIs, because of the possible effects of addition and overcoming
the toxic dose (risk of Serotonin Syndrome: characterized by abdominal pain, diarrhea, cutaneous vasodilation, sweating, hyperthermia, tremor, sedation,
myoclonus and, in severe cases, rhabdomyolysis or shock).
Avoid the use, frail as MAO inhibitor stimulates uterine contractions.
You need to stop taking it five days prior to any surgery.
Numerous pharmacological and clinical studies carried out on the plant, show that St. John's wort is a plant safe,
but it may have some drawbacks such as sensitivity to light during exposure to sunlight
during the period for which the recruitment is good to avoid exposure to the sun and / or tanning lamps, especially
if the patient is taking other photosensitizing drugs, such as chlorpromazine, or tetracycline.
In recent years, research has been done on the possible utility of hypericum and dell'iperacina,
in anbito doctor. Below are some of the last areas in which they moved searches:
-POSSIBLE ACTION ANTI-TUMOR:
The team of researchers led by Adriana Albini, Head of Oncology Research IRCCS MultiMedica
recently found that hyperforin has anti-angiogenic properties, which fights the cells that
form blood vessels of tumors.
The mechanism passes through the inhibition of NFkB molecule, a main switch circuits
inflammation and inflammatory angiogenesis. Also blocks the migration of the endothelium in response to cytokines
Mechanisms of hyperforin as an anti-angiogenic agent angioprevention.
-ROLE IN prevention of Alzheimer's:
The hypericin may interfere with the processes of polymerization of beta-amyloid peptides linked to the occurrence
of Alzheimer's disease. Researchers at the Institute of Biophysics of the National Research Council in Pisa (IBF-CNR), and Antonella Sgarbossa
Francesco Lenci, have demonstrated that hypericin, via intermolecular interactions of type aromatic / hydrophobic,
may be associated with precursors of mature fibrils, inhibiting their formation.
Alzheimer's disease is characterized by the formation and accumulation of protein aggregates in the brain under
form of highly stable and insoluble amyloid fibrils, several studies seem to agree on the idea that
toxicity is rather due to smaller pools, which are present in the early and intermediate stages of the process of
fibril formation: these oligomers "pre-fibrillar", soluble and unstable, have a strong tendency to
interact with biological macromolecules and cellular structures
Hypericin, as many aromatic molecules that, thanks to their physical-chemical properties, can interact with
amyloid-beta peptides, sequestering and inactivating the toxic forms.