English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

St. John's wort ( Hypericum perforatum)  is an ancient folk remedy that has antiviral and antibacterial properties. Anti-inflammatory effects of the plant have been described and the application of  H. perforatum  extract as an effective antidepressant is well established. In this study we assayed the effect of  H. perforatum  extract on cytokine-induced tryptophan degradation in human peripheral blood mononuclear cells. Simultaneously, changes in the production of the immune activation marker neopterin were monitored. Both these biochemical pathways are triggered by interferon-γ. Our results show that extracts of  H. perforatum  strongly down-regulate mitogen-mediated tryptophan degradation in a dose-dependent manner. This effect seems to be based on a suppressive activity of  H. perforatum  on activated immunocompetent cells, resulting in a diminished production of interferon-γ. In line with this finding, neopterin synthesis was strongly down-regulated by the plant extract. Our results suggest that the reduction of tryptophan degradation by  H. perforatum  might be important in the action of the plant as an antidepressant.

St. John's wort ( Hypericum perforatum ) counteracts cytokine-induced tryptophan catabolism in vitro