Abstract
Medicinal plants and their extracts are natural remedies with enormous potential for
treating various diseases, including depression and anxiety. In the case of depression,
hundreds of plants have traditionally been used in folk medicine for generations.
Different plant extracts and natural products have been analyzed as potential antidepressant
agents with validated models to test for antidepressant-like effects in animals, although
other complementary studies have also been employed. Most of these studies focus on
the possible mediators implicated in these potential effects, with dopamine, serotonin,
and noradrenaline being the principal neurotransmitters implicated, both through interference
with receptors and with their metabolism by monoamino oxidases, as well as through
neuro-endocrine and neuroprotective effects. There are approximately 650 reports of
antidepressant-like medicinal plants in PubMed; 155 of them have been compiled in
this review, with a relevant
group yielding positive results. Saffron and turmeric are the most relevant species
studied in both preclinical and clinical studies; St. Johnʼs wort or kava have also
been tested extensively. To the best of our knowledge, no review to date has provided
a comprehensive understanding of the biomolecular mechanisms of action of these herbs
or of whether their potential effects could have real benefits. The purpose of this
narrative review is to provide an update regarding medicinal plants from the year
2000 to the present to examine the therapeutic potential of these antidepressant-like
plants in order to contribute to the development of new therapeutic methods to alleviate
the tremendous burden that depression causes worldwide.
Key words
medicinal plants - mood disorders - depression - antidepressant-like effect - herbal
medicine - pro-inflammatory mediators - preclinical trials