External stress causes neural, endocrine, and immune responses in the human body. Normally, stress in life raises blood levels of adrenaline and prostaglandins that increase heart rate, respiratory rate, and blood pressure. Long-term stress results in increased cardiovascular disease.
Panossian defines plant adaptogens as compounds that “increase the ability of an organism to adapt to environmental factors and to avoid damage from such factors.” Adaptogens improve the body’s defenses to external stresses and modulate pathologic reactions to stress. Plant adaptogens taken by humans improve mental performance and improve physical capacity by central nervous system stimulation.
If people are on repeated dose adaptogens benefit due to an improved ability to handle repeated stress by improved functioning of the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis involves the hypothalamus of the brain, the pituitary, and the adrenal glands. This axis is one nervous system mechanism that the body has for dealing with stress. The HPA controls the body’s reaction to stress by changing the release of adrenaline, corticosteroids, and nitric oxide. Adrenaline is called a “switch-on” hormone and corticosteroids act as a “switch-off” modulator of the stress reaction. Nitric oxide has widespread activity in response to stress.
Single dose adaptogens behave differently. They stimulate the sympatho-adrenal-system (SAS) involving the sympathetic nervous system and the adrenal glands. This system is adapted for a rapid resonse to stress. This article by Panossian, et al, is about the response of the SAS to Rhodiola rosea (rhodiola,) Schizandra chinensis (schizandra,) and Eleuthrococcus senticosus (eleuthro was formerly called Siberian ginseng) in single doses.
The three herbs work by way of the following chemicals: phenylpropane- and phenylethane-based phenolic compounds (salidroside, rosavin, syringin, and triandrin.) Adaptogens stimulate the nervous system without the side effects seen with caffeine, nicotine, cocaine, and amphetamines. These side effects include dependence, tolerance, abuse potential, and “hangover effect.” The benefit of the single dose herbs comes in about 30 minutes and lasts for 4-6 hours.
Rhodiola has an “anti-fatigue” effect and has been shown to improve the quality of mental work especially by reducing mental errors. Rhodiola does not seem to reduce the time required to do mental tasks except by reducing time wasted by mistakes.
Schizandra increases endurance and capacity to do physical work. There is mild stimulation and increased sympathetic tone with schizandra that improves cardiovascular performance, increases physical strength, and increases physical speed.
Schizandra increases peripheral vision, increases sensitivity to red light, increases night vision, and improves adaptation to darkness. Ninety percent of healthy subjects who received a single dose of 3 gm. of schizandra seed powder showed significant increase of visual sensitivity. The improved visual sensitivity was felt to be due to increased neural responses.
Eleuthro improved resistance to infections and external stressors and increases parasympathetic tone. Eleuthro has been shown to increase the ability of skiers to do work and to stimulate a rapid recovery after a heavy workload. One study showed that rhodiola and eleuthro increased physical capacity especially if the patients were pre-fatigued with exercise. This was especially true for rhodiola.
Rhodiola, schizandra, and eleuthro contain high amounts of phenolic compounds, especially phenylpropane and phenylethane derivatives which are closely related to catecholamines and are important in the SAS and the central nervous systems.
The HPA system regulates the immune and neuroendocrine systems and is stimulated by Panax ginseng, Bryonia alba, and Eleuthrococcus senticosus. These herbs contain tetracyclic triterpenes that are similar to corticosteroids. Their protective effects come after repeated doses for 1-4 weeks.
CONCLUSION: Single dose administrtation of rhodiola, schizandra, and eleuthro improved mental and physical functioning with little side effects and work by way of the SAS system and have a stimulating effect.
Rhodiola was the most active, increasing mental performance in terms of learning and memory. Schizandra chinensis is hepatoprotective, improves night vision, improves stamina, and increases work capacity. Eleuthrococcus senticosus increases resistance to viral and bacterial infections, and increases resistance to external stress.
To read the author’s abstract of the article click on the link to the author’s tile of the article above.
PMID: 16261511.
Summary #097.
