What is rare ginsenoside?
Ginsenosides or “Prototype ginsenosides” are major active compounds in Araliaceae ginseng spices like Panax ginseng, American ginseng, Notoginseng, Japanese ginseng and Panax vietnamensis. Prototype ginsenosides are tetracyclic triterpenoids. Their metabolic and transformed derivatives are academically called “rare ginsenosides”(i.e. Rg3, Rh1, C-K, Rh2, Rg5, Rk1, Rh3, Rk2, Rh4, Rk3, aPPT, aPPD, etc.)
Since ginsenosides were found to exhibit anticancer activities in the 1960s, a number of scientists and pharmacists have devoted themselves to the ginsenoside research. During this courses, scientists found that rare ginsenosides processed by transformation and metabolization exhibit more bioactivities, and they can inhibit malignant cell growth and metastasis, induce cell death and differentiation, reverse cell resistance to drugs.
Comparison of the activity of rare ginsenosides
Canadian scientists determined the activity of some rare ginsenosides in experiments and the results are shown as follows:
Rg3 <Δ 20-22 PPD = Rg5 ≤ aPPT = Rk1/Rg5 = Rh2 ≤ Δ (20-21) PPD <aPPD = Δ (20-21) PPT = Δ (20-22) PPT = Rk2/Rh3 ≤ Rk2 =Δ (20-21) PPD/Δ (20-22) PPD
Furthermore, scientists found that rare ginsenosides show different anticancer effects on different cancers. For example, some rare ginsenosides exhibit a more strong inhibitory effect on lung cancer cells, while others are more sensitive to liver cancer cells. Still, some can enhance the efficacy of chemotherapy drugs, while others can reduce the side effects of chemotherapy drugs. The effect of one rare ginsenoside is often limited in fighting cancers but Combining several together may exert a synergistic anticancer effect.
5 proven ginseng and rare ginsenosides benefits
1.Enhancing cardiovascular health
In the paper “Therapeutic potential of ginseng in the management of cardiovascular disorders”, Morris Karmazyn, a researcher with Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario London Canada, together with his team members reviewed a number of experimental studies and acknowledged ginseng and ginsenosides’ potential in combating cardiovascular disorders. In many experimental models, ginseng and ginsenosides are proved beneficial to protecting the ischaemic and reperfused heart and alleviating hypertension.
2.Stimulating immune function
Researchers from Department of Immunology, Beijing Institute of Geriatrics conducted an experiment on two age groups. 10 young people and 19 elderly people were involved and Scientists cocultured lymphocytes of two groups for 72 h with PHA and ginsenoside Rg1. This experiment found that the elderly have lower the CD25 and CD45RA positive cells of lymphocytes but have more CD45RO positive cells, compared with the young people, which indicated that ginsenoside Rg1 shows a positive mechanism of action beneficial to the strengthening of the immune system.
3.Increasing resistance to stress
An Indian scientist in his paper “Anti-stress effects of Ginkgo biloba and Panax ginseng: a comparative study” presented pharmaceutical properties of Indian ginseng and Asian ginseng in fighting stress. The research compared the effects of Ginkgo biloba and Panax ginseng on the changes of some biochemical parameters like plasma glucose (GL), triglycerides (TG), cholesterol (CL), creatine kinase (CK), and serum corticosterone (CORT) which are important indicators for measuring stress. The research results showed that both Ginkgo biloba and Panax ginseng have anti-stress activities, and more specifically, Ginkgo biloba is more effective in acute stress while Panax ginseng will be a better option for chronic stress.
4.Enhancing learning and memory
The researchers from Department of Psychology, Georgia College and State University Zhao R and McDaniel WF, explored possible mechanism of action of ginseng on improving strategy learning. In trial 1, when tested with an elevated rotating rod, brain-damaged rats administrating ginseng extract showed improved learning deficit. In trial 2, with added difficulty in the reverse rotating rod, the rats taking higher dose presented better performance in learning and cognitive abilities.
5.Combating cancers in chemoprotective and chemotherapeutic activities
Scientists of the Republic of Korea summarized the functional roles of ginseng-derived compounds in cancer in the paper “Functional role of ginseng-derived compounds in cancer”, which is a really good overview of ginsenosides’ anticancer activities. As is shown in the following table, ginsenosides can help inhibit the invasion, migration, angiogenesis of cancerous cells, and meanwhile, they can be used in the cancer treatment to reduce the side effects of anticancer drugs thanks to their good chemoresistance.
Mechanisms of action of rare ginsenosides in fighting cancer
1. Inhibiting angiogenesis in malignant lesions
The angiogenesis in malignant lesions experiences an extremely complicated process. Malignant cells obtain nutrients at their most power by making new blood vessels. Rare ginsenosides could modulate a multitude of pro- and anti-angiogenic factors, inhibit Human Umbilical Vein Endothelial Cell (HUVEC) proliferation, inhibit angiogenesis in malignant lesions, block nutritional supply to malignant cells and decelerate proliferation.
2. Alleviating toxicity induced by chemotherapy and radiotherapy and increasing drug sensitivity
Both chemotherapy and radiotherapy cause severe toxic side effects either in a long-term or in a short term. Many parts of the body including the respiratory system, urinary system, immune system and nervous system risk of being damaged. Rare ginsenosides obviously alleviate toxicity induced by chemotherapy and radiotherapy. Meanwhile, they increase the sensitivity of malignant cells to chemotherapy and radiotherapy drugs, improve therapeutic efficacy and reduce the number of malignant cells in vivo.
3. Reversing multiple drug resistance of malignant cells and delaying drug-resistant cycle
Multidrug resistance is the principal mechanism by which many cancers develop resistance to chemotherapy drugs, rare ginsenosides were shown to reverse drug resistance in drug-resistance tumor cell lines, thus improving the potency of chemotherapy drugs.