11.24.08
Chinese Herbal Extracts and Antioxidant Activities
Resource:
How to Use Herbs in Chinese Medicine: The Basics and Practical Guides
Many Chinese herbs have been found to have antioxidant activities. For example, Rhodiola sachlinesis, A. Bor is one of the most popular traditional Chinese herbs. It contains many effective compounds, including flavonoids, anthraglycosides, essential oil with cinnamic aldehyde, as well as citral and organic acids.
A group of Chinese researchers developed a new method of extraction called “ultrahigh pressure extraction (UPE)†to extract flavonoids from the herb R. sachlinesis (Zhang et al., 2008). They tested the antioxidant activity of the crude extract of R. sachlinesis. They found that it has a higher activity than that of tertiary butyhydroquinone (TBHQ) at the same concentration.
Another study done in Texas investigated the effects of a mixture of herbal extracts called Tong-Xin-Luo (TXL) (Zhang et al., 2008). The herbal mixture has been used in Chinese medicine for the treatment of coronary artery disease. The researchers examined the protection of TXL extracts on endothelial cells damaged by palmitic acid (PA). Palmitic acid is known to increase metabolic syndromes and has been connected with cardiovascular diseases.
The study showed that palmitic acid induced more than seventy percent of apoptosis in endothelial cells. Apoptosis is programmed cell death. However, when the cells were pretreated with extracted TXL, PA could induce apoptosis in only 7% of the cells.
They also examined the possible mechanisms of such protective effects of the herbal extract. They found that TXL could reduce PA-induced oxidative stress and inhibit PA-induced activation of the p38-MAPK stress pathway. TXL could restore the intracellular antioxidant system that was damaged by the PA treatment. TXL could also enhance the expression of thioredoxin, with a reduced expression of the thioredoxin interacting protein.
Their study suggests that the Chinese herbal extract TXL has the effect of protecting endothelial cells from palmitic acid-induced damages. The herbal extract has intracellular antioxidant capacity that may contribute to its therapeutic effects for cardiovascular diseases.
These examples demonstrate that certain Chinese herbs may be potent antioxidants. They can be used for the protection from oxidative stress and for the treatment of diseases such as cardiovascular diseases and cancer. They may function as antioxidants through repairing oxidative damages and working on certain molecular stress pathways.
References:
Zhang, S., C. Liu, et al. (2008). Extraction of flavonoids from Rhodiola sachlinesis A. Bor by UPE and the antioxidant activity of its extract. Nat Prod Res 22(2): 178-87.
Zhang, L., Y. Wu, et al. (2008). Protective effects of a compound herbal extract (Tong Xin Luo) on free fatty acid induced endothelial injury: implications of antioxidant system. BMC Complement Altern Med 8: 39.
