ST JOHN'S WORT

ST JOHN'S WORT 化学特性,用途語,生産方法

• 天然物の起源

  St. John's wort is found in Europe, Asia, and the United States.

• 使用

  St. John's wort is used to treat mild to moderate depression and anxiety. It may be used topically as an antiinfl ammatory to relieve hemorrhoids, as well as to treat vitiligo and burns.

• 適応症

  St. John’s wort (Hypericum perforatum) is a yellowflowered perennial European herb that has become widely naturalized in the United States. Its name is derived from the Old English word for plant, wort, and from the fact that it often starts blooming around June 24, St. John’s day. Although St. John’s wort has traditionally been used for wound healing, insomnia, rheumatism, and depression, it is most popular today for the treatment of mild to moderate depression.
  The leafy parts of the herb contain naphthodianthrones (e.g., hypericin), flavonoids (e.g., quercetin), and phloroglucinols (e.g., hypaphorine). Although this herb is now commonly standardized for its hypericin content, it appears that its other constituents may also be just as pharmacologically active.

• 作用機序

  Just how St. John’s wort treats depression is not clearly understood. It is possible that this herb’s various components may work synergistically rather than through a single active substance, mimicking the action of traditional antidepressants. High concentrations can affect in vitro serotonin reuptake, but it is unclear whether this would occur in a patient taking standard oral doses.The hypaphorine constituent may possess serotonin reuptake inhibitor activity, and it also inhibits synaptic uptake of  amino butyric acid (GABA) and L-glutamate. Earlier studies demonstrated some monoamine oxidase inhibition, but this action now seems unlikely to be clinically relevant. Flavonoid components and hypericin also may weakly inhibit catechol-O-methyl-transferase (COMT). Melatonin, surprisingly, has also been identified in St. John’s wort and may play a role in its sleepenhancing and antidepressant effects.

• 臨床応用

  St. John’s wort is very popular as a physician-prescribed antidepressant in Europe and is widely used for this purpose—usually without medical guidance—in the United States.A meta-analysis of 23 studies concluded that St. John’s wort was more effective than placebo in treating mild to moderate depression and was as effective as imipramine and standard antidepressants. It was also better tolerated than the antidepressants to which it was compared. A recent meta-analysis, however, failed to find St. John’s wort effective for severe depression.

ST JOHN'S WORT 生産企業

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