Hypericum perforatum L. (St John's wort) extract Ze 117 inhibits dopamine re-uptake in rat striatal brain slices. An implication for use in smoking cessation treatment?

Documentary Analysis of Hypericum perforatum (St. John's Wort) and Its Effect on Depressive Disorders

Hypericum perforatum, also known as St. John's Wort, pericon, or yellow grass, is known for its antidepressant potential. It could represent a natural alternative to current pharmacological antidepressant treatments, which have a high incidence of side effects in patients and therefore lead to early dropouts. Through a bibliographic revision of clinical trials and information collected from scientific articles during the first period of 2020, we aimed to evaluate whether its administration could be beneficial in the treatment of mild-to-moderate depression, with fewer side effects compared to synthetic drugs. Among the main components, hypericin and hyperforin have been related to the observed antidepressant activity; therefore, their possible mechanism of action was reviewed and highlighted. Furthermore, patients receiving Hypericum extracts were less likely to withdraw from studies because of adverse effects compared to those receiving older standard antidepressants. This review aims to provide suggestions for an alternative treatment of mild-to-moderate depression disorder under the supervision of a medical doctor, since, although it appears to be a potentially efficient treatment with a low presence of adverse effects in comparison to synthetic antidepressants, it might also interact with other medications and lead to therapeutic failures if misused for self-medication.

St. John's wort (Hypericum perforatum) and depression: what happens to the neurotransmitter systems?

St. John's wort (Hypericum perforatum) is a herbaceous plant containing many bioactive molecules including naphthodianthrones, phloroglucinol derivatives, flavonoids, bioflavonoids, proanthocyanidins, and chlorogenic acid. Evidence has shown the therapeutic effects of St. John's wort and especially its two major active components, hyperforin and hypericin, on different psychiatric and mood disorders such as posttraumatic stress disorder (PTSD), attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), and anxiety disorders. St. John's wort also induces antidepressant effects. In this review study, we aimed to discuss the role of St. John's wort in modulating depression, with respect to the role of different neurotransmitter systems in the brain. We discussed changes in the neurotransmitter levels in depression, and following use of St. John's wort. It was concluded that changes in the function and level of neurotransmitters in depression are complex. Also, St. John's wort can induce inconsistent effects on neurotransmitter levels. We also found that glutamate and acetylcholine may be the most important neurotransmitters to study in future works, because the function of both neurotransmitters in depression is unclear. In addition, St. John's wort induces a dualistic modulation on the activity of cholinergic signaling, which can be an interesting topic for future studies.

Clinical relevance of St. John's wort drug interactions revisited

The first clinically relevant reports of preparations of St. John's wort (SJW), a herbal medicine with anti‐depressant effects, interacting with other drugs, altering their bioavailability and efficacy, were published about 20 years ago. In 2000, a pharmacokinetic interaction between SJW and cyclosporine caused acute rejection in two heart transplant patients. Since then, subsequent research has shown that SJW altered the pharmacokinetics of drugs such as digoxin, tacrolimus, indinavir, warfarin, alprazolam, simvastatin, or oral contraceptives. These interactions were caused by pregnane‐X‐receptor (PXR) activation. Preparations of SJW are potent activators of PXR and hence inducers of cytochrome P450 enzymes (most importantly CYP3A4) and P‐glycoprotein. The degree of CYP3A4 induction correlates significantly with the hyperforin content in the preparation. Twenty years after the first occurrence of clinically relevant pharmacokinetic drug interactions with SJW, this review revisits the current knowledge of the mechanisms of action and on how pharmacokinetic drug interactions with SJW could be avoided.

Linked Articles

This article is part of a themed section on The Pharmacology of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.6/issuetoc

Hypericum Perforatum Hydroalcoholic Extract Mitigates Motor Dysfunction and is Neuroprotective in Intrastriatal 6-Hydroxydopamine Rat Model of Parkinson's Disease

Parkinson's disease is the second most common neurodegenerative disorder with selective and progressive decline of nigral dopaminergic neurons. Hypericum perforatum L. (H. perforatum, St. John's wort) has been traditionally used for management of different disorders, especially mild-to-moderate depression. This study was conducted to evaluate the effect of H. perforatum extract against unilateral striatal 6-hydroxydopamine (6-OHDA) toxicity and to unmask some involved mechanisms. Intrastriatal 6-OHDA-lesioned rats were treated with H. perforatum hydroalcoholic extract at a dose of 200 mg/kg/day started 1 week pre-surgery for 1 week post-surgery. The extract attenuated apomorphine-induced rotational behavior, decreased the latency to initiate and the total time on the narrow beam task, lowered striatal level of malondialdehyde and enhanced striatal catalase activity and reduced glutathione content, normalized striatal expression of glial fibrillary acidic protein, tumor necrosis factor α with no significant effect on mitogen-activated protein kinase, lowered nigral DNA fragmentation, and prevented damage of nigral dopaminergic neurons with a higher striatal tyrosine hydroxylase immunoreactivity. These findings reveal the beneficial effect of H. perforatum via attenuation of DNA fragmentation, astrogliosis, inflammation, and oxidative stress.

The Effects of Lavandula Angustifolia Mill Infusion on Depression in Patients Using Citalopram: A comparison Study

BACKGROUND

Many herbs have been used to treat psychiatric disorders including anxiety and depression in traditional medicine.

OBJECTIVES

This study was carried out to determine the effect of using Lavandula angustifilia infusion on depression in patients taking Citalopram.

PATIENTS AND METHODS

Among all patients referred to the Hajar Hospital psychiatric clinic, Shahrekord, Iran, 80 patients who met the criteria of major depression according to the structured interviews and the Hamilton questionnaire for Depression were included in the study. They were randomly assigned into two groups of experimental treatment group and standard treatment group at this study. In standard treatment group, the patients were given Citalopram 20 mg. In experimental treatment group, the patients took 2 cups of the infusion of 5 g dried Lavandula angustifilia in addition to tablet Citalopram 20 mg twice a day. The patients were followed up for four and eight weeks of the study onset using Hamilton Scale questionnaire and treatment side effects form. Data were analyzed using student t-test, pair t-test and chi square.

RESULTS

After four weeks of the trial onset, the mean depression score according to the Hamilton Scale for Depression was 17.5 ± 3.5 in the standard treatment group and 15.2 ± 3.6 in the experimental treatment group (P < 0.05). After eight weeks, it was 16.8±4.6 and 14.8±4 respectively (P < 0.01). In addition, the most commonly observed adverse effects were nausea (12.8 %) and confusion (10%). In terms of side effects, there were no significant differences between two groups.

CONCLUSIONS

Considering the results of this study, Lavandula angustifilia infusion has some positive therapeutic effects on depressed patients most importantly decreases mean depression score and might be used alone or as an adjunct to other anti-depressant drugs.

Elicitation of secondary metabolism in Hypericum perforatum by rhizosphere bacteria and derived elicitors in seedlings and shoot cultures

CONTEXT

Hypericum perforatum L. (Guttiferae) appears as an alternative treatment to mild and moderate depression and been traditionally used as a health enhancer based on the phytochemicals hyperforin and hypericin. However, field grown medicinal plants show variable levels of phytopharmaceuticals depending on environmental conditions. Elicitation is a good strategy to trigger secondary metabolism.

OBJECTIVE

This study explored the ability of 6 rhizobacterial strains to trigger secondary metabolism in H. perforatum seedlings and molecular elicitors from the most effective strain N5.18 were tested in shoot cultures.

MATERIALS AND METHODS

Hypericin and pseudohypericin were determined on seedlings and shoot cultures by HPLC. Three putative elicitors from bacterial culture media were assayed in three different concentrations.

RESULTS

Strain N5.18 significantly increased hypericin up to 1.2 ppm and pseudohypericin up to 3.4 ppm, over controls (0.3 and 2.5 ppm, respectively) when delivered to seedlings. In shoot cultures, only pseudohypericin was detected (168.9 ppm) and significant increases were observed under the different elicitors, reaching values of 3164.8 ppm with small elicitors in the middle concentration.

DISCUSSION AND CONCLUSION

Secondary metabolism in plants is highly inducible due to its role in plant communication and defense. Our findings demonstrate that some beneficial bacterial strains are able to trigger secondary metabolism in H. perforatum plants when delivered through the roots and bacterial determinants released to culture media are able to reproduce the effect in shoot cultures. Therefore, these elicitors have great potential to enhance phytopharmaceutical production.