1. Composition
The plant rhizome of rhodiola rosea initially consists of many compounds including essential oils, fats, waxes, sterols, glycosides, organic acids such as oxalic, citric, malic, gallic, and succinic as well as phenolics including tannins and proteins. [1] The dried rhizome contains a mere 0.05% essential oil of which the most important subset for supplementation, Geraniol, consisted of 12.49% by weight.[2]
Geraniol's oxygenated metabolite Rosiridol and the compound Rosiridin (of which the former is an aglycon of) are considered the most active essential oil of Rhodiola Rosea supplementation.
Other non-essential oil compounds of Rhodiola Rosea include the polar water extracts such as polyphenols, flavonoids, proanthycyanidins, and gallic acid derivatives (amongst others).[3]. The water soluble component with the most biological activity in vivo was determined to be p-hydroxyphenylethyl-O-ß-D-glucopyranoside, more commonly known as Salidroside (also known as Rhodioloside or Rhodosin)[4]
The proanthocyanidin content of the water solubles consisted a great deal by weight (50-70%) and is credited for Rhodiola Rosea's potential anti-oxidant, anti-cancer, anti-inflammatory, anti-allergic, anti-mutation, anti-aging and liver health properties.[5]
Rhodiola Rosea is used above other species of Rhodiola due to it's comparatively high Rosavin (essential oil) content while still having an appreciable salidroside content.
Edit2. SHR-5
Rhodiola Rosea SHR-5 is a standardized extract of Rhodiola Rosea that is used in most human studies. When buying Rhodiola Rosea it is advisable to seek this specific standardization on the label.
Edit3. Pharmacology
In the body, Rhodiola Rosea (in regards to the Rosiridin, Rosiridol and Salidroside contents) has been found to be:
•
Neuroprotective against hypoglycemia[6], excitotoxicity from glutamate[7][8] and oxidation from beta-amyloids[9] and hydrogen peroxide radicals[10]
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Cardioprotective by protecting cardiomyocytes against Ischemia[11][12]
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Anti-diabetic by increasing glucose uptake into myocytes via activation of AMPK[13], as well as protecting neurons from periods of hypoglycemia, which is of interest to management treatment. Rhodiola Rosea may also act as a low-grade ACE inhibitor[14]
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Hepatoprotective against tacrine-induced toxicity (although another species of Rhodiola was used in which the compounds Kaempferol is confounded)[15] and agaisnt acetominophen-induced toxicity[16]
Most of the protection effects of Rhodiola Rosea seem to be from the Salidroside component, whereas mood and cognition seem to come from the essential oil subsets of Rosiridin/Rosiridol.
The 'adaptogenic' effects of Rhodiola Rosea, alleviating the stress response, arise mainly from the ability of Rhodiola Rosea to minimize the cellular mechanisms responsible for initiating the stress response in the hypothalamus. This includes cortisol, protein kinases p-JNK, heat shock proteins, and some signaling proteins (DAF-16, FoxO) used in the stress response[17]
It is suspected that Rhodiola Rosea might be a valuable addition to treatment programs for depression due to it's lack of interactions with some other medications such as theophylline or warfarin[18]
Edit4. MAOI Activity
The Rosiridin subset of Rhodiola Rosea was found to act as an inhibitor of both Monoamine Oxidase A and B.[19]
This is one of the reasons Rhodiola Rosea may exert itself as a cognitive booster and anti-neurodegenerative agent, but caution should be taken when pairing any MAOI with other agents that increase monoamines such as dopamine or adrenaline.
Edit5. Cognition
5.1. Fatigue
In humans, Rhodiola Rosea has been shown on numerous occasions to reduce fatigue, improve mood, and alleviate stress in conditions as far ranging from exam periods,[20] general stress,[21][22][23] and stress-related depression.[24]
Edit6. Interactions with Exercise and Performance
6.1. Acute Usage
Effects on humans using Rhodiola Rosea as an acute ergogenic aid to increase exercise performance are mixed. With some results showing no significant difference[25][26] and some showing benefits.[27] It is suspected that this may be an issue of herbal potency (variations in active ingredients due to growing conditions) and a supposed bell-shaped curve of Rhodiola Rosea activity, in which it is ineffective in low doses and very high doses.[28]
One study using an acute dose of 3mg/kg bodyweight of SHR-5 (3% Rosavins, 1% Salidroside) noted that ingestion of the supplement prior to a 10k bicycle ride showed significantly reduced time to complete the ride (25.4 minutes relative to 25.8 minutes) and reduced heart rate during the warmup (136+/-17 relative to placebo's 140+/-17) but not during exericse, which alongside average power output and cadence only trended towards improvement.[29] This study was conducted in recreationally fit women, and the subjects reported less subjective fatigue after consumption of Rhodiola Rosea.[29]
Scientific Support & Reference Citations
Rosenroot (Rhodiola rosea: traditional use, chemical composition, pharmacology and clinical efficacy)
Stimulating effect of adaptogens: an overview with particular reference to their efficacy following single dose administration
Evidence-based efficacy of adaptogens in fatigue, and molecular mechanisms related to their stress-protective activity
References
1.Panossian A, Wikman G, Sarris J. Rosenroot (Rhodiola rosea): traditional use, chemical composition, pharmacology and clinical efficacy. Phytomedicine. (2010)
2.Rohloff J. Volatiles from rhizomes of Rhodiola rosea L. Phytochemistry. (2002)
3.Phytoconstituents and Anti-oxidant potency of Rhodiola Rosea - A versatile Adaptogen
4.Effects of Adaptogens on the Central Nervous System and the Molecular Mechanisms associated with their Stress - Protective Activity
5.Comparative phytochemical characterization of three Rhodiola species
6.Neuroprotective Effects of Salidroside in the PC12 Cell Model Exposed to Hypoglycemia and Serum Limitation
7.Cao LL, Du GH, Wang MW. The effect of salidroside on cell damage induced by glutamate and intracellular free calcium in PC12 cells. J Asian Nat Prod Res. (2006)
8.Chen X, et al. Salidroside attenuates glutamate-induced apoptotic cell death in primary cultured hippocampal neurons of rats. Brain Res. (2008)
9.Zhang L, et al. Neuroprotective effects of salidroside against beta-amyloid-induced oxidative stress in SH-SY5Y human neuroblastoma cells. Neurochem Int. (2010)
10.Chen X, et al. Protective effect of salidroside against H2O2-induced cell apoptosis in primary culture of rat hippocampal neurons. Mol Cell Biochem. (2009)
11.Zhong H, et al. Salidroside attenuates apoptosis in ischemic cardiomyocytes: a mechanism through a mitochondria-dependent pathway. J Pharmacol Sci. (2010)
12.Zhang J, et al. Salidroside protects cardiomyocyte against hypoxia-induced death: a HIF-1alpha-activated and VEGF-mediated pathway. Eur J Pharmacol. (2009)
13.Li HB, et al. Salidroside stimulated glucose uptake in skeletal muscle cells by activating AMP-activated protein kinase. Eur J Pharmacol. (2008)
14.Kwon YI, Jang HD, Shetty K. Evaluation of Rhodiola crenulata and Rhodiola rosea for management of type II diabetes and hypertension. Asia Pac J Clin Nutr. (2006)
15.Song EK, et al. Hepatoprotective phenolic constituents of Rhodiola sachalinensis on tacrine-induced cytotoxicity in Hep G2 cells. Phytother Res. (2003)
16.Wu YL, et al. Protective effects of salidroside against acetaminophen-induced toxicity in mice. Biol Pharm Bull. (2008)
17.The Adaptogens Rhodiola and Schizandra Modify the Response to Immobilization Stress in Rabbits by Suppressing the Increase of Phosphorylated Stress-activated Protein Kinase, Nitric Oxide and Cortisol
18.Panossian A, et al. Pharmacokinetic and pharmacodynamic study of interaction of Rhodiola rosea SHR-5 extract with warfarin and theophylline in rats. Phytother Res. (2009)
19.van Diermen D, et al. Monoamine oxidase inhibition by Rhodiola rosea L. roots. J Ethnopharmacol. (2009)
20.A double-blind and placebo controlled pilot study on the effects of Rhodiola Rosea SHR-5 extract on the fatigue of students caused by stress during an examination period with a repeated low dose regimen
21.Fintelmann V, Gruenwald J. Efficacy and tolerability of a Rhodiola rosea extract in adults with physical and cognitive deficiencies. Adv Ther. (2007)
22.Schutgens FW, et al. The influence of adaptogens on ultraweak biophoton emission: a pilot-experiment. Phytother Res. (2009)
23.Olsson EM, von Schéele B, Panossian AG. A randomised, double-blind, placebo-controlled, parallel-group study of the standardised extract shr-5 of the roots of Rhodiola rosea in the treatment of subjects with stress-related fatigue. Planta Med. (2009)
24.Darbinyan V, et al. Clinical trial of Rhodiola rosea L. extract SHR-5 in the treatment of mild to moderate depression. Nord J Psychiatry. (2007)
25.Earnest CP, et al. Effects of a commercial herbal-based formula on exercise performance in cyclists. Med Sci Sports Exerc. (2004)
26.Colson SN, et al. Cordyceps sinensis- and Rhodiola rosea-based supplementation in male cyclists and its effect on muscle tissue oxygen saturation. J Strength Cond Res. (2005)
27.De Bock K, et al. Acute Rhodiola rosea intake can improve endurance exercise performance. Int J Sport Nutr Exerc Metab. (2004)
28.Perfumi M, Mattioli L. Adaptogenic and central nervous system effects of single doses of 3% rosavin and 1% salidroside Rhodiola rosea L. extract in mice. Phytother Res. (2007)
29.Noreen EE, et al. The Effects of an Acute Dose of Rhodiola Rosea on Endurance Exercise Performance. J Strength Cond Res. (2012)
30.Hung SK, Perry R, Ernst E. The effectiveness and efficacy of Rhodiola rosea L.: a systematic review of randomized clinical trials. Phytomedicine. (2011)
