Ginseng is one of the most popular medicinal plants that has long been highly reputed for its health-promoting benefits in East Asian countries. It also has enjoyed enormous popularity since introduced to western countries where a quite number of people use ginseng to improve their energy and stamina.
The bioactivities of ginseng may be beyond your expectations. Some medicinal benefits of ginseng include:
- promote healthy glucose levels
- support cognitive function and reduce mental fatigue
- support cognition
- enhance physical capacity or performance
- increase energy and resistance to stress
Moreover, Ginseng exhibits significant antioxidant, anti-inflammatory and antitumor bioactivities in many studies, which indicates that ginsenosides may help fight against various diseases and cancer.
It is easy to positively associate ginseng consumption with brain health, but when it comes to neurodegenerative diseases like Alzheimer’s disease, it may be hard to decide whether ginseng is still effective.
Since ginseng has been found to support cognition, there are sure to be some mechanisms of action of ginseng on neuroprotection.
The primary pharmacologically active ingredients, called ginsenosides, are responsible for a collection of health effects of ginseng. For this reason, scientists put their focus on ginsenosides to explore the effects of ginsenosides on neurodegenerative diseases.
Lab and animal studies have indicated that ginsenosides can improve brain function, prevent neuroinflammation and oxidative stress and reduce neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease, traumatic brain injury, and Huntington’s disease.
Ginsenoside Rg1 is a naturally existing ginsenoside in fresh ginseng, and it was found to affect the nervous system to help treat elderly Alzheimer’s disease. Unfortunately, ginsenoside Rb1 has extremely low bioavailability because it is easily degraded by intestinal bacteria through oral administration before reaching the brain area.
Ginsenoside Rb1 is also positively correlated with Alzheimer’s disease and it can protect hippocampal neurons by fighting against neurotoxins. For example, ginsenoside Rb1 in a recent animal model study showed neuroprotective effects by promoting neural growth, upregulating the expression of health-promoting enzymes, and suppressing neural cell apoptosis.
A few studies have been conducted in humans to investigate the efficacy of ginsenoside on the treatment of neurodegenerative disease.
A study, published in the Journal of Research in 2018 by South Korea researchers, was conducted to figure out whether Korean red ginseng (KRG）supported the cognitive function among patients with Alzheimer’s disease. The trial included a small population of 61 patients randomly assigned to low-dose KRG, high-dose KRG or control groups, and the cognitive function of patients was evaluated at the end of the 12-week trial. The study results that patients with high-dose KRG show a significant improvement in Alzheimer’s disease.
The number of related human studies is very limited, and more human studies are needed to confirm the therapeutic effects of ginseng and ginsenosides on neurodegenerative diseases like Alzheimer’s disease.
In addition, improving the bioavailability of ginsenosides remains a huge challenge in order to make full use of ginseng.
Researchers have metabolized some types of rare ginsenosides from naturally existing ginsenosides through unique preparation technologies. Compared with prototype ginsenosides in ginseng, rare metabolized ginsenosides are more bioactive and easily absorbed by the human body. Some well-known rare metabolized ginsenosides include Rh2, Rg3, Rk2, Rh3, aPPD, compound K, etc.
To sum up, ginseng and ginsenosides can be promising therapeutic agents for neurodegenerative diseases like Alzheimer’s disease, however, there is still a long way to go in studying their mechanisms and clinical effects.