HERBCLIP
™
• Adaptogens • Ashwagandha (Withania somnifera) • Shatavari (Asparagus racemosus) • Guduchi (Tinospora cordifolia)
FILE: • Ayurvedic Herbs
Post Office Box 144345 Austin, Texas 78714-4345 Phone 512/926-4900 Fax 512/926-2345 Email: abc@herbalgram.org www.herbalgram.org
Mark Blumenthal Editor Wayne Silverman, PhD Underwriting Coordinator Leela Devi, MSN, RN Mariann Garner-Wizard Betsy Levy Heather Oliff, PhD Risa Schulman, PhD Michele Schuman Densie Webb, PhD Summary Writers Karen Robin Susan McFarland Coordinators Dawnelle Malone Research Assistant The American Botanical Council provides this summary and the enclosed article as an educational service. By providing this article, ABC does not warrant that the data is accurate and correct, nor does distribution of the enclosed article constitute any endorsement of the information contained or of the views of the authors. ABC does not authorize the copying or use of the original articles. Reproduction of the summaries is allowed on a limited basis for students, colleagues, employees and/or customers. Other uses and distribution require prior approval.
DATE: June 30, 2000
HC 011005
RE: Ayurvedic Herbs Tested for Adaptogenic Activity
Rege, N.N., U.M. Thatte, and S. A. Dahanukar. Adaptogenic properties of six Rasayana herbs used in Ayurvedic medicine. Phytotherapy Research, 1999; Vol. 13, pp. 275-291.
Adaptogens are agents that counteract any adverse physical, chemical, or biological stressors by producing a non-specific response. According to Brekhman and Dardymov (1969), they also have a normalizing influence without influencing normal body functions more than required. Numerous plants including Eluthero, (Eleutherococcus senticosus, aka Siberian ginseng), Asian ginseng (Panax ginseng), Raponticum carthamoides, Golden root (Rhodiola rosea), ashwagandha (Withania somnifera), and holy basil (Ocimum sanctum) have been studied extensively for their adaptogenic potential. In animal experiments they are capable of modulating stress related changes; however, none of them has been successfully introduced in the modern medical market under the heading adaptogen. The researchers discuss the problems in evaluating adaptogens, which usually precludes their inclusion as clinically useful drugs. Also, the researchers evaluate the adaptogenic potentials of six rasayana plants from the Ayurvedic tradition in India. There are numerous problems related to the evaluation of an adaptogen. One of the major obstacles is the non-availability of good experimental or clinical stress models. When using the available stress models, quantification of the stressor is not always possible, which is not ideal. Aside from these technical problems, scientists do not know enough about the body’s stress response. They do not know the first mediator of the body’s stress reaction and whether the response is the same against different stressors. Variations between individual animals or humans may also be a problem. Ayurvedic pharmacology—Indian traditional medicine—groups medicinal plants according to their actions. Rasayana is an ayruvedic group of plant medicines that strengthen or promote the health of all body tissues. The plants are said to prevent aging, re-establish youth, strengthen life and brain power, and prevent disease by increasing the body’s resistance. The researchers chose to examine the following plants from the rasayana group: Tinospora cordifolia Miers. (guduchi; dried stem), Asparagus racemosus
Willd. (shatavari; dried root), Emblica officinalis Gaertn. (amalki; dried fruit), Withania somnifera Dunal. (ashwagandha; dried root), Piper longum Linn. (pippali; dried fruit), and Terminalia chebula Retz. (haritaki; dried fruit). The objectives were to find out if the plants fulfill the criteria of Brekhman and Dardymov for adaptogens, to explore and compare the mechanisms responsible for the adaptogenic potential, and to determine whether the protection provided by the plant was equivalent against all stressors or more effective against particular stressors. The whole, aqueous standardized extracts were processed in the same manner as prescribed in Ayurveda. The actual method of preparation is detailed for each herb. The dose given to animals was extrapolated from the human dose. All animals were orally pretreated with the herb for 7-15 days prior to exposure to a biological, physical, or chemical stressor. The plants were also evaluated in different animal strains, in normal or immunosuppressed animals, and in animals with organ dysfunction. Thirteen different stress-models were evaluated. Such stress models include hepatotoxicity induced by carbon tetrachloride, gastric mucosal damage induced by aspirin or ethanol, cold immobilization test, and more. In general, the plants were capable of protecting against a variety of stressors, although the degree of protection varied depending on the stressor and plant tested. None of the agents exhibited any toxic effects or mortality at any dose level tested. Both acute and subacute administration was safe. Therefore, the authors conclude that the plants fulfilled the criteria put forth by Brekhman and Dardymov for an adaptogenic drug. Protection by the extracts was not equal against all the stressors. For example, the degree of protection provided by Tinospora cordifolia and Asparagus racemosus was greater than that provided by Withania somnifera. Also, the extent of adaptogenic protection may not be equal for all organs. It is not known why the adaptogen may have specific affinity for one particular organ. It may be related to the pharmacokinetics of the herb—such as the ability to reach a particular organ in sufficient concentration. All of the plants possessed immunostimulant activity. It is unclear whether the immunostimulation is responsible for the adaptogenic potential. Moreover, immunostimulation may not be the sole mechanism for the adaptogenic effect. For example, Emblica officinalis may be directly cytoprotective without involving the neuroendocrine or immune systems. In conclusion, T. cordifolia, E. officinalis, and A. racemosus exerted significant anti-stress effects against a battery of stressors. Their mechanism of action may vary and may depend on the type of extract used. For example, the aqueous extract of W. somnifera failed to be active. The extracts need to be given as a pretreatment for best action. The authors suggest that plants that show experimental promise should be developed into clinically effective formulations. —Heather S. Oliff, Ph.D.
Enclosure: The American Botanical Council was unable to secure permission from the publisher for the original article to be enclosed with this HerbClip summary. Bin #176