Introduction

Rhodiola is widely distributed at high altitudes in mountainous regions over the world. It is commonly used in traditional medicine in Asia for stimulating the nervous system, enhancing work and exercise performance, eliminating fatigue and preventing mountain sickness. There are over 200 different species of Rhodiola and about 20 of them are used in Asian traditional medicine, such as Rhodiola crenulata, Rhodiola rosea and Rhodiola sacra. Rhodiola rosea in particular, has been extensively studied for several decades. It has been categorized as an adaptogen by Russian scientists due to its ability to increase resistance against a variety of chemical, biological and physical stressors and to help the body to recover homeostasis. Beside its traditional functions, newly discovered properties such as anticancer and anti-diabetic effects have become new areas of Rhodiola research in recent years.

Traditional Uses of Rhodiola rosea

Anti-hypoxia

Hypoxia is a pathological condition in which the body is deprived of oxygen supply. Generally, it occurs in normal people at high altitudes, where it causes altitude sickness and other potentially fatal complications. When hypoxia develops gradually, the symptoms include headaches, fatigue, shortness of breath and nausea. Severe cases or sudden onset of hypoxia may cause coma or even death. R. rosea has been categorized as an adaptogen due to its ability to increase resistance against physical, chemical and biological stress. When a stressful situation (e.g. hypoxia) occurs, R.rosea, acting as an adaptogen, can generate a degree of generalized adaptation or non-specific resistance that allows human physiology to handle this stressful situation. It may prevent hypoxia-induced biological changes by either increasing intracellular oxygen diffusion and efficiency of oxygen utilization or reducing hypoxia-induced oxidative damage with its anti-oxidative ability.¹

Modern Pharmacological Mechanism

Improve exercise endurance

R. rosea has been used to improve or maintain endurance performance of athletes during training or competition by increasing biological factors associated with oxygen uptake. In-vivo experiments have shown that oral treatment with R. rosea extracts in rats can significantly prolong the duration of long-distance swimming and activate the synthesis or re-synthesis of ATP in mitochondria which acts as the main energy source for majority cellular functions and is essential for locomotion and respiration.² Mitochondrial ATP content decreased in both control and Rhodiola extracts groups in the study. However, the decrease of ATP is less pronounced in rats receiving R.rosea treatment. Therefore, it is suggested that R. rosea extracts can activate ATP synthesis or re-synthesis in muscles during exercise which helps increase the physical capacity and promote body recovery after intense exercise such as marathons.

Anti-oxidative and anti-diabetic ability

Recently, studies show that oxidative stress plays an important role in pathogenesis of human diseases such as cancer, cardiovascular disease, diabetes mellitus, neurodegenerative diseases and rheumatoid arthritis. R. rosea extract has been used as an anti-diabetic folk medicine.³ An animal study was designed to examine the effect of R. rosea on the level of blood glucose, glutathione (GSH) and its related enzymes, and the activity of antioxidant enzymes such as catalase and superoxide dismutase (SOD) in type II diabetic mice.⁴ It is found that R. rosea extract significantly lowers the blood glucose level and increases the level of reduced GSH. It can also activate the enzymatic functions of catalase and SOD. Therefore, use of R. rosea extract may be effective for correcting hyperglycemia and preventing diabetic complications.

Anticancer property

Some reports also indicate that R.rosea has an anticancer and anti-mutagenic effect. The mechanism of this effect was studied based on cell-cycle progression, induction of apoptosis and mitotic activity by using various cancer cells with flow cytometry and fluorescence microscopy. A study, published in 2006, found that extract of R.rosea inhibits division of HL-60 leukemia cells and reduces their survival. The accumulation of cells in the prophase (G2/M phase) leads to induction of apoptosis and necrosis in HL-60 cells.⁵ Administration of R.rosea can also directly suppress the growth and metastasis of Lewis lung cancer carcinomas.⁶

Conclusion

A wide spectrum of scientific research on R. rosea has been designed in different fields of medicine. Based on the proposed mechanism of action and available experimental results, it has a number of functions which include anti-oxidative, anti-diabetic, anti-hypoxia and anticancer effects. It is one of the most promising of traditional herbal medicines. Scientists should obtain more insights on its effectiveness through further clinical studies.

References

1. IP, S.P. et al. Association of free radicals and the tissue rennin-angiotensin system: prospective effects of rhodiola, a genus of Chinese herb, on hypoxia-induced pancreatic injury. J. Pancreas 2, 16-25 (2001). Full text
2. Abidov, M. et al. Effects of extracts from rhodiola rosea and rhodiola crenulata (crassulaceae) roots on ATP content in mitochondria of skeletal muscles. Bull. Exp. Biol. Med. 136, 585-587 (2003). Online abstract
3. Valko, M. et al. Free radicals and antioxidants in normal physiology functions and human disease. Int. J. Biochem. Cell Biol. in press (2006) Online abstract
4. Kim S.H. et al. Antioxidative effects of cinnamomi cassiae and rhodiola rosea extracts in liver of diabetic mice. Biofactors 26, 209-219 (2006). Online abstract
5. Majewska, A. et al. Antiproliferative and antimitotic effect, S phase accumulation and induction of apoptosis and necrosis after treatment of extract from rhodiola rosea rhizomes on HL-60 cells. J. Ethnopharmacol. 103, 43-52 (2006). Online abstract
6. Udintsev S.N. et al. Decrease of cyclophosphamide haematotoxicity by rhodiola rosea root extract in mice with ehrich and lewis transplantable tumors. Eur. J. Cancer 27, 1182 (1991)

Further Reading

Kelly, GS. Rhodiola rosea: a possible plant adaptogen. Altern. Med. Rev. 6, 293-302 (2001). Full text Top

Compiled and edited by:

Jennifer Eagleton, BA, MA (Asian Studies), Integrated Chinese Medicine Holdings Ltd. Stan Man, Integrated Chinese Medicine Holdings Ltd.