Korean Ginseng, Alzheimer’s and Parkinson’s Disease
Ginseng (Panax ginseng) is a classic tonifying herb used to support health, energy and wellbeing in Chinese Medicine. Over the last several decades, research has been expanding into its use to support and prevent neurodegenerative conditions, including Alzheimer’s and Parkinson’s disease. While the clinical trial data is minimal, mechanistic and animal studies suggest some potential in its use for improving and restoring brain health.
Mechanisms of Action
Antioxidant Activity
Free radicals are damaging compounds that can be produced or found in the human body. Antioxidants defend against free radicals and free radical damage. Free radicals have been implicated as a part of the disease process in numerous brain conditions, including Alzheimer’s and Parkinson’s disease (Domenico 2015, Blesa 2015).
Ginseng has well-studied antioxidant effects. A number of human clinical trials have shown that taking ginseng improves antioxidant parameters found in the bloodstream. Studies in healthy subjects have found improved antioxidant enzyme activities and decreased markers of free radical damage with ginseng supplementation (Kim 2003, Kim 2005, Kim 2011).
Smoking is well known to cause free radical damage. A study of ginseng on smokers also found increased antioxidant activity with reduced markers of free radical damage (Lee 1998). Exercise is also known to increase free radical activity. A number of studies have demonstrated that ginseng can help to reduce free radical damage from exercise (Kim 2005, Flanagan 2018).
Anti-inflammatory Activity
Cell-line and animal studies have found anti-inflammatory effects with ginseng extracts (Baek 2016). Studies on immune cells found in the brain, called microglia, have also shown anti-inflammatory activity (Park 2009). These anti-inflammatory effects may prove helpful for neurodegenerative diseases.
One of the constituents of ginseng, ginsenoside Rd, has been studied specifically for its effects in stroke patients. The compound improved stroke outcomes with reduced disability. The benefits were thought to be due, at least in part, to reduced inflammation throughout the brain (Zhang 2015).
Alzheimer’s Disease and Ginseng
Human trials are starting to suggest that ginseng may have direct positive effects on Alzheimer’s patients. An early trial administered ginseng powder and found benefits as early as four weeks, with further improvements in cognition by three months (Lee 2008). A similar three-month study using higher doses found improved cognitive performance as well (Heo 2008).
A longer six-month study explored heat-processed ginseng for Alzheimer’s disease. Heat processing is known to increase the potency of ginseng. In the high-dose group, patients with moderately severe Alzheimer’s disease derived significant benefits in both cognitive and non-cognitive symptoms of Alzheimer’s that were sustained through the course of the study (Heo 2012).
Parkinson’s Disease and Ginseng
Parkinson’s disease is a progressive loss of specific brain cells that causes slowly worsening levels of muscular dysfunction. Animal models have repeatedly suggested potential benefits of ginseng for the condition. Administering ginseng before and after a toxin that induces Parkinson’s-like symptoms found improved brain cell survival and muscle control (Kampen 2003). In a more recently developed model of the disease that mimics it’s slow development, supplementation with ginseng blocked damage to the brain and fully prevented the development of problems with mobility (Kampen 2014).
A more recent study also found similar benefits. In the study, ginseng yielded improvements with supplementation. These improvements were thought to be related to the antioxidant and anti-inflammatory activity of the herb. Ginseng was found to decrease brain cell death and maintain the blood-brain barrier with supplementation (Choi 2018). Numerous other animal studies have found similar potential benefits of ginseng for Parkinson’s disease (Kim 2016, Zaafan 2019, Jeon 2020, Jun 2015)
Conclusion
Korean ginseng appears to hold promise in neurodegenerative diseases, including Alzheimer’s disease and Parkinson’s. And while initial studies appear promising, larger and longer human clinical trials are needed to provide more definitive results. Considering the minimal side effects from taking ginseng, it could prove to be a safe and useful tool to help prevent some of the most dreaded diseases associated with aging.
