Reversal of Multidrug Resitance by Natural Substances from Plants.
Summary of "Reversal of Multidrug Resitance by Natural Substances from Plants."
The multidrug resistance (MDR) proteins that belong to the ATP-binding cassette superfamily such as P-glycoprotein (P-gp) and MRP1, are present in a majority of human tumors and constitute an important cause of therapeutic failure. Selective inhibitors of the MDR-efflux proteins may improve the effectiveness of cancer chemotherapy. Their mechanism of action was believed to be a competition between resistance modifiers and drugs for the same binding site of P-gp. In our previous work we studied modulation of MDR in cancer cells expressing P-gp or MRP1 by selected carotenoids, flavonoids and extracts from medically important Chinese plants. Capsanthin and capsorubin, carotenoids isolated from paprika, were identified as potent P-gp inhibitors, while lycopene, lutein, antheraxanthin and violaxanthin induced moderate effects. Among flavonoids, effective modulators were rotenone, chrysin, phloretin and sakuranetin. Some chloroform extracts of Chinese herbs were also found to inhibit MDR efflux pumps. The effects of the modulators on P-gp activity were studied by measuring rhodamine 123 uptake in several cancer cells such as the human MDR1 gene-transfected mouse lymphoma cells (L1210) and human breast cancer cells MDA-MB-231 expressing the MRP1 pump (HTB26). Additionally, the ability to alter biophysical properties of lipid bilayers by selected carotenoids was studied by differential scanning calorimetry. The antiproliferative effects as well as the MDR reversal activity of the studied compounds, applied in combination with anticancer drugs, were also discussed.
Institute of Medical Microbiology and Immunobiology, University of Szeged, H-6720 Szeged, Dóm tér 10. Hungary. firstname.lastname@example.org.
This article was published in the following journal.
Name: Current topics in medicinal chemistry
Samples of sieve-tube sap were obtained as honeydew from aphids feeding on three species of higher plants. The honeydew was extracted, chromatographed and tested in several bioassays for the presence ...
Flavonoids have always attracted much attention due to their reversal activity on multidrug resistance (MDR). Eight flavonoids isolated from traditional Chinese medicine Sophora alopecuroides L. were ...
Natural products represent the fourth generation of multidrug resistance (MDR) reversal agents that resensitize MDR cancer cells overexpressing P-glycoprotein (Pgp) to cytotoxic agents. We have develo...
This paper examines the transmission of B chromosomes in natural (but controlled) pollination, in order to obtain results which can be applied to natural populations of rye. The frequencies of the fem...
(2-Chloroethyl)trimethylammonium chloride (Cycocel or CCC), an inhibitor of gibberellin biosynthesis, when repeatedly supplied to the root systems of balsam (Impatiens glandulifera Royle) plants reduc...
Isolated minority communities in China use traditional plant-based methods of mosquito control. This study is evaluating 4 plants used in this way by monitoring mosquitoes entering houses...
The purpose of this study is to assess the extent of symptom remission in patients with trichotillomania following treatment with sertraline and/or behavior therapy.
In this trial will be investigated if a defunctioning loop stoma used in low anterior resection of the rectum for cancer can be reversed after 14 days instead of 3-12 months which is prese...
An Open-label, Randomized, Multicenter Phase IIIb Study to Assess the Efficacy, Safety and Tolerance of BERIPLEX® P/N Compared With Plasma for Rapid Reversal of Coagulopathy Induced by Vitamin K Antagonists in Subjects Requiring an Urgent Surgical Proced
The purpose of this study is to evaluate efficacy, safety and tolerance of Beriplex® P/N compared with plasma in regard to rapid reversal of coagulopathy induced by vitamin K antagonists ...
The purpose of this study was to demonstrate in adult patients faster recovery from a neuromuscular block induced by either rocuronium or vecuronium after reversal at reappearance of T2 by...
Medical and Biotech [MESH] Definitions
The science of drugs prepared from natural-sources including preparations from PLANTS, animals, and other organisms as well as MINERALS and other substances included in MATERIA MEDICA. The therapeutic usage of plants is PHYTOTHERAPY.
Procedures to reverse the effect of REPRODUCTIVE STERILIZATION and to regain fertility. Reversal procedures include those used to restore the flow in the FALLOPIAN TUBE or the VAS DEFERENS.
Toxic substances from microorganisms, plants or animals that interfere with the functions of the nervous system. Most venoms contain neurotoxic substances. Myotoxins are included in this concept.
Complete or partial change from one sex to another with regard to gonadal development. Gonadal sex reversal may occur naturally or be induced by factors such as steroids, temperature, and autosomal abnormalities during the critical period of gonadal differentiation (SEX DIFFERENTIATION) in some species.
Specific substances elaborated by plants, microorganisms or animals that cause damage to the skin; they may be proteins or other specific factors or substances; constituents of spider, jellyfish or other venoms cause dermonecrosis and certain bacteria synthesize dermolytic agents.