Inflammation is considered a major physiological defense mechanism, helping the body protect itself against infections, burns, toxic chemicals, allergens or other toxic irritants. Uncontrolled inflammation may be a factor in chronic diseases. Now, there is a number of analgesic anti-inflammatory drugs which belong to nacotics, corticosteroids and nonsteroidal drugs. However, most of them have side effects.
Eurycoma longifolia Jack is also known as Alipas ginseng belonging to Simaroubaceae. This plant grows throughout our country but is most common in the Centre, the Central Highlands and the southern province of Tay Ninh. In Malaysia and Indonesia, this plant is a valuable medicinal herb with the common name - Tongkat Ali. People use dried fruit, stem or root bark as medicine. According to Oriental medicine, the tree has a bitter taste and warmth, and is used to treat many diseases such as indigestion, diarrhea, vomiting, dysentery, scabies, pimples and back pain.
Thanks to recent studies, many compounds from the tree have been isolated. The chemical composition of the plant is extremely rich and diverse, including compounds of the diterpenoid and triterpen groups with three basic frameworks: quassinoid, aquallan, tirucallan and alkaloid, steroid, flavon. In which quassinoid and alkaloid layers play a major biological role of the tree. Studies show diverse effects such as anti-malarial parasite, cytotoxicity, sexual enhancement, anti-diabetes, anti-inflammatory and prevention of osteoporosis. In Vietnam, as well as in the world, many products from the tree have been developed, mainly focusing on products that enhance the sexual and nutritious effects. However, so far the anti-inflammatory effects of this plant have not been paid much attention.
Scientists from the Institute of Marine Biochemistry, Vietnam Academy of Science and Technology (VAST), have studied the anti-inflammatory effect of the tree in the results of the project: “Research on isolating of alkaloid active group from Eurycoma longifolia Jack and assessing anti-inflammatory effects on in vitro and in vivo”- VAST04.03/17-18 chaired by Dr. Nguyen Hai Dang, from 2017 to 2018. The project has been evaluated as Excellent by the VAST Acceptance Council on August 8, 2019.
After two years of implementation, the project has isolated and determined the structure of 19 compounds from the tree root, including 10 alkaloid compounds, 06 quassinoid compounds, 03 phenolic compounds, especially 4 new compounds including eurycomalide F, G, H and eurylongilactone A.
Alkaloid compound structure isolated from the tree root
Structure of non-alkaloid compounds isolated from the tree root
In terms of biological activity, the project evaluated in vitro and in vivo anti-inflammatory activity of total residue, fraction, and compounds isolated from the tree root. Alkaloid ELA rich residue is good for NO inhibiting reproduction with IC50=28.18 µg/mL. Testing on molecular biological targets confirms that ELA effectively inhibits the expression of two enzymes involved in the inflammatory process, including iNOS and COX-2, at test concentrations of 50-150 µg /mL. Test results on mice showed that ELA residues at doses of 50 and 100 mg kg of body weight prevented the ability of mice to die from septic shock when injected with LPS. The anti-inflammatory effect of ELA on mice model caused by ELAS’s carragenan at 250 mg kg of body weight was also demonstrated.
The compounds 9,10-dimethoxycanthin-6-one (EL3), eurylongilactone A (EL16) and ethyl ferulate (EL19) have impressive NO inhibition activity with IC50 values of 23,11, 3.03 và 3.56 µM respectively. EL3 compounds isolated with high concentrations were selected to assess the effectiveness on molecular biological targets. Results showed that EL3 has effective in inhibiting of expression of two enzymes iNOS and COX-2.
Effect of EL3 compound at 1 1M, 3 µM, 10 µM to iNOS, COX-2 protein expression on RAW264.7 cell line stimulated by LPS
In addition to the above results, the project has published three scientific works, including two international articles on the SCIE list and one domestic article, contributing to training two Masters in the field of research.
Translated by Tuyet Nhung
Link to Vietnamese version