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High-resolution Tandem Mass Spectrometry for Studying Chemical Constituents of Gynura bicolor DC
Published on: February 2, 2024
Steroids, alkaloids, and coumarins from Gelsemium sempervirens
Zhizhen Zhang1, Ping Wang, Wei Yuan
1National Center for Pharmaceutical Crops, Arthur Temple College of Forestry and Agriculture, Stephen F. Austin State University, Nacogdoches, Texas, USA.
Planta Medica
|November 19, 2008
Summary
Gelsemium sempervirens extract inhibits human DNA topoisomerase I (Topo I). Sempervirine, a key compound, intercalates DNA and modulates Topo I activity, suggesting potential anticancer applications.
Area of Science:
- Natural Product Chemistry
- Biochemistry
- Pharmacology
Background:
- Gelsemium sempervirens is a plant with known medicinal properties.
- Human DNA topoisomerase I (Topo I) is a crucial enzyme in DNA replication and a target for cancer therapy.
Purpose of the Study:
- To investigate the phytochemical constituents of Gelsemium sempervirens extract.
- To evaluate the inhibitory activity of these compounds against human Topo I.
Main Methods:
- Phytochemical isolation and structure elucidation using NMR and HR-ESI-MS.
- In vitro assays to determine Topo I inhibitory activity and DNA intercalation.
Main Results:
- Three new steroids (1-3) and eleven known compounds were isolated.
- Sempervirine (6) demonstrated significant Topo I inhibition (IC50 = 54.5 ± 15.9 μM) and DNA intercalation.
Conclusions:
- Gelsemium sempervirens contains compounds with Topo I inhibitory activity.
- Sempervirine is a promising candidate for further development as an anticancer agent targeting Topo I.
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