Ginseng effectively regulates the immune response and the hormonal changes due to stress, thus maintaining homeostasis. In addition to suppressing the occurrence of psychological diseases such as anxiety and depression, ginseng also prevents stress-associated physiological diseases. Recent findings have revealed that ginseng is involved in adjusting the hypothalamic–pituitary–adrenal axis and controlling hormones, thus producing beneficial effects on the heart and brain, and in cases of bone diseases, as well as alleviating erectile dysfunction. Recent studies have highlighted the potential use of ginseng in the prevention and treatment of chronic inflammatory diseases such as diabetes, rheumatoid arthritis, and allergic asthma. However, the mechanism underlying the effects of ginseng on these stress-related diseases has not been completely established. In this review, we focus on the disease pathways caused by stress in order to determine how ginseng acts to improve health. Central to our discussion is how this effective and stable therapeutic agent alleviates the anxiety and depression caused by stress and ameliorates inflammatory diseases.
In order to survive, all organisms must manage the physical and psychological effects of a variety of stressful situations. Stress represents a necessary response that maintains in vivo homeostasis upon exposure to environmental changes. When affected by a certain stressor, changes occur in the human body. This programmed response is known as a stress response. Stress can be divided into four types: chronic eustress (too little stress), acute stress (optimum stress), acute distress (too much stress), and chronic stress (burnout). When stress increases beyond a certain level, it leads to adverse health effects. Furthermore, chronic stress can cause depression and/or anxiety . Thus, in this review, we will consider the beneficial effects of ginseng on the multidimensional symptoms and typical diseases caused by stress.
Ginseng is traditionally used as a medicinal herb in Korea, Japan, China, and the United States , . The reason for this long-established usage is that ginseng contains natural antioxidant compounds. These ginsenosides, which are extracted from the ginseng roots, leaves, stems, and fruit, have multiple pharmacological effects. They are subdivided into about 100 different categories . In many studies, ginsenosides have been presented as an effective treatment for organ damage and cell death, as well as for immunological and metabolic diseases , , . In addition, these pharmacologically active constituents have been shown to support neurogenesis, synaptogenesis, neuronal growth, and neurotransmission, thus helping to protect the central nervous system from unexpected events; ginseng is also reported to be excellent for improving memory , .
As a powerful natural antioxidant, ginseng effectively modulates apoptosis by reducing the excessive inflammatory response in acute or chronic inflammation . Abnormal apoptosis can result in functional impairment of organs. The human body contains many different protein types, and their interactions maintain the balance of mechanisms related to proliferation, differentiation, and apoptosis. When this homeostasis is disturbed, it can damage the immune system and lead to several fatal diseases , .
Many studies conducted over the past decade have revealed that ginseng has a range of positive effects on the human body, but a systematic perspective on the efficacy of ginseng in the treatment of stress in vivo is not available. Therefore, this review will consider whether ginseng modulates human stress-related changes and diseases, and evaluate how ginseng could potentially act as a therapeutic agent for stress-induced diseases.
Although existing drug treatments are often effective, continuous exposure to medicinal products can sometimes cause addiction or undesirable side effects. Moreover, population aging is increasing susceptibility to infectious diseases because of attenuated immune system function. Therefore, new treatment methods are required. Future studies should consider investigating alternatives to conventional drugs, such as medicinal plants. These have been used for more than a thousand years and generally carry a low risk of negative side effects. Ginseng provides a potential approach to regaining homeostasis after abnormal physiological changes caused by the stress of everyday life. The efficacy of this preparation has been demonstrated in various experiments conducted using human cells and animal models. A clearer understanding of the mechanisms underlying the effects of ginseng on human cytokine/metabolic systems and on stress-induced hormonal changes could facilitate the development of a wide range of treatments for patients with psychological and physical diseases.