Adaptogens as anti-stress agents in reducing increased plasma cortisol level during stress

Abstract

The stress response involves the activation of both the sympathetic-adrenal response and the hypothalamic-pituitary-adrenal axis. During times of increased stress, the adrenal gland is stimulated to produce increased levels of hormones. Cortisol, the main hormone involved in the stress response, is secreted in increased amounts within minutes of a perceived stressor. Cortisol secretion can increase as much as 20-fold and has several important physiological effects. Short-term surges in cortisol levels can suppress inflammation and at the same time suppress immune function. Though inflammation control is important, surges of sustained levels of cortisol are not healthy and ultimately lead to premature aging, degenerative disease, and increased susceptibility to cancer. Studies show that psycho-social stress activates the hypothalamus-pituitary-adrenal axis causing an increase in morning cortisol levels, which correlated to the subjects reports of increased fatigue and anxiety. Although this stress response is important for survival during an acute stressor, prolonged activation of the stress response may lead to adrenal exhaustion in which cortisol levels drop to insufficient levels resulting in fatigue or illness. Many herbs have been shown to impact adrenal function. Adaptogens are plants that produce a non-specific response improving the physiological resistance to stressors. These herbs are often used in the context of adrenal support formulas to balance adrenal hormone levels. It is believed that adaptogenic herbs can increase low levels of adrenal hormone or decrease levels that are elevated. Additionally, these herbs provide balancing activity on many body systems that are impacted by stress, such as the immune response and blood sugar control.In the present study, we have evaluated the efficacy of ethanolic extract of Ocimum sanctum 47mg/kg p.o, Withania somnifera 23 mg/kg p.o and Bacopa monnieri 23 mg/kg p.o on plasma cortisol level in mice subjected to swim endurance test and cold restraint stress. The standard group was administered water-soluble root powder of Panax ginseng 100 mg/kg p.o and the stress control group was administered distilled water orally for 7 days. It was found that mice pretreated with ethanolic extracts of Ocimum sanctum, Withania somnifera and Bacopa monnieri showed a fall in the plasma cortisol level. The standard group also showed a significant decrease in the plasma cortisol level compared to the stress and normal control groups.