| Rhodiola rosea | |
|---|---|
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Core eudicots |
| Order: | Saxifragales |
| Family: | Crassulaceae |
| Genus: | Rhodiola |
| Species: | R. rosea |
| Binomial name | |
| Rhodiola rosea L.[1] |
|
| Synonyms | |
|
Sedum rosea (L.) Scop. |
|
Rhodiola rosea (Golden Root, Roseroot, Aaron's Rod) is a plant in the Crassulaceae family that grows in cold regions of the world. These include much of the Arctic, the mountains of Central Asia, the Rocky Mountains, and mountainous parts of Europe, such as the Alps, Pyrenees, Carpathian Mountains, Scandinavia, Iceland, Great Britain and Ireland. The perennial plant grows in areas up to 2280 meters elevation. Several shoots grow from the same thick root. Shoots reaches 5 to 35 cm in height. Rhodiola rosea is dioecious – having separate female and male plants.
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Rhodiola rosea may be effective for improving mood and alleviating depression. Pilot studies on human subjects[2][3][4] showed that it improves physical and mental performance, and may reduce fatigue.
Rhodiola rosea's effects are potentially mediated by changes in serotonin and dopamine levels due to monoamine oxidase inhibition and its influence on opioid peptides such as beta-endorphin,[5] although these specific neurochemical mechanisms have not been clearly documented with scientific studies.
Rhodiola is included among a class of plant derivatives called adaptogens which differ from chemical stimulants, such as nicotine, and do not have the same physiological effects.
In Russia and Scandinavia, Rhodiola rosea has been used for centuries to cope with the cold Siberian climate and stressful life.[6] Such effects were provided with evidence in laboratory models of stress using the nematode C. elegans,[7] and in rats in which Rhodiola effectively prevented stress-induced changes in appetite, physical activity, weight gain and the estrus cycle.[8]
Rhodiola has been used in traditional Chinese medicine, where it is called hóng jǐng tiān (红景天).
The dried rhizomes contained essential oil with the main chemical classes: monoterpene hydrocarbons, monoterpene alcohols and straight chain aliphatic alcohols were the most abundant volatiles detected in the essential oil, and a total of 86 compounds were identified (Rohloff, 2002). Geraniol was identified as the most important rose-like odor compound besides geranyl formate, geranyl acetate, benzyl alcohol and phenylethyl alcohol. Its oxygenated metabolite Rosiridol is an aglycon of Rosiridin (Kurkin et al., 1985a; Kurkin and Zapesochnaya, 1986b) - one of the most active constituents of Rhodiola in bioassay guided fractionation of Rhodiolathe extract.[9] Rosiridin was found to inhibit monoamine oxidases A and B in vitro implying its potential beneficial effect in depression and senile dementia.[9] More than 50 polar compounds were isolated from the water alcoholic extracts, they are: monoterpene alcohols and their glycosides, cyanogenic glycosides, phenylethanoids and phenylpropanoids, flavonoids, aryl glycosides, proanthocyanidins and other gallic acid derivatives. (Zapeschnaya, and Kurkin, 1983, 1983; Kurkin et al., 1985a; Kurkin, and Zapesochnaya, 1986a,b; Ganzera et al., 2001; Tolonen et al.,2003; Saratikov and Krasnov, 2004; Akgul et al., 2004; Ma et al.2006, Yousef et al., 2006, Ali et al.,2008; Avula et al., 2008).
Rhodiola rosea contains a variety of compounds that may contribute to its effects,[10] including the class of rosavins which include rosavin, rosarin, and rosin. Several studies have suggested that the most active components are likely to be rhodioloside and tyrosol,[11] with other components being inactive when administered alone, but showing synergistic effects when a fixed combination of rhodioloside, rosavin, rosarin and rosin was used.[12]
Although rosavin, rosarin, rosin and salidroside (and sometimes p-tyrosol, rhodioniside, rhodiolin and rosiridin) are among suspected active ingredients of Rhodiola rosea, these compounds are mostly polyphenols for which no physiological effect in humans is proved to prevent or reduce risk of disease.[13]
Although these phytochemicals are typically mentioned as specific to Rhodiola extracts, there are many other constituent phenolic antioxidants, including proanthocyanidins, quercetin, gallic acid, chlorogenic acid and kaempferol.[14][15]
While animal tests have suggested a variety of beneficial effects for Rhodiola rosea extracts[16] there is scientific evidence only for depression as a benefit in humans. A clinical trial showed significant effect for a Rhodiola extract in doses of 340–680 mg per day in male and female patients from 18 to 70 years old with mild to moderate depression.[17]
Rodiola Rosea promotes the release of NO from rat penile corpus cavernosum smooth muscle cell and artery endothelium cell, which was correlated with the effect of Rodiola Rosea to resist senility.[18]
Rhodiola rosea extract SHR-5 exerts an anti-fatigue effect that increases mental performance, particularly the ability to concentrate in healthy subjects[19][20][21] and burnout patients with fatigue syndrome.[22] Rhodiola significantly reduced symptoms of fatigue and improved attention after four weeks of repeated administration.[23]
Studies on whether Rhodiola improves physical performance have been inconclusive, with some studies showing some benefit,[24] while others show no significant difference.[25]
Inhibitory activities against HIV-1 protease have also been studied.[26]
Rhodiola rosea extract is mainly used in the form of capsules or a tablet, though tinctures are also available. The capsules and tablets often contain 100 mg of a standardized amount of 3 percent rosavins and 0.8–1 percent salidroside because the naturally occurring ratio of these compounds in Rhodiola rosea root is approximately 3:1. Authentication as well as potency of golden root crude drug materials and standardized extracts thereof are carried out with validated RP-HPLC analyses to verify the content of the marker constituents salidroside, rosarin, rosavin, rosin and rosiridin.[27] However, as with many plant-based remedies, an approved dosage range in relation to the active constituents has officially not been established. In these cases, dosage recommendations of the individual manufacturers should be followed.
A typical dosage is one or two capsules or tablets daily; one in the morning and when taking two, one in the early afternoon. Rhodiola rosea should be taken early in the day because for some it can interfere with sleep. Others can take it in the evening with no effect on sleep patterns. If a user becomes overly activated, jittery or agitated then a smaller dose with very gradual increases may be needed. It is contraindicated in excited states.
The dose may be increased to 200 mg three times a day if needed. A high dose is considered to be daily intakes of 1,000 mg and above.
Rhodiola rosea may be beneficial to increase energy and mental performance for people suffering from Hashimoto's disease.
In a 2007 clinical trial from Armenia, total effective doses were in the range of 340–680 mg per day for people aged 18 to 70. No side effects were demonstrated at these doses in the treatment of mild to moderate depression.[28]
29. Panossian, A., Wikman, G. 2010. Rosenroot (Roseroot): Traditional Use, Chemical Composition, Pharmacology, and Clinical Efficacy. Phytomedicine 17(5-6): 481-493. DOI 10.1016/j.phymed.2010.02.002
30. Bozhilova, M. 2011. Salidroside content in Rhodiola rosea L., dynamics and varyability. In: Botanica Serbica 35 (1): 3-6. http://botanicaserbica.bio.bg.ac.rs/arhiva/pdf/2011_35_1_533_full.pdf
Critical of effects on mountain sickness