Presentation Title

Inhibition of DNA oxidative damage by green tea in vitro and in human melanoma cells

Faculty Mentor

Eric Stemp

Start Date

18-11-2017 2:15 PM

End Date

18-11-2017 3:15 PM

Location

BSC-Ursa Minor 41

Session

Poster 3

Type of Presentation

Poster

Subject Area

physical_mathematical_sciences

Abstract

Oxidative damage is involved in the formation of free radicals, which can cause various diseases. Oxidation was effected by the flash-quench technique In our experiment, samples containing Ru(phen)2dppz2+(phen = 1,10-phenanthroline, dppz = dipyridophenazine), Co(NH3)5Cl2+, histone protein, calf thymus DNA and either water or green tea were irradiated for 0-4 minutes with 442 nm light from a HeCd laser to effect guanine damage. The extent of crosslinking was determined by the chloroform extraction assay, whereby protein and DNA-protein crosslink is extracted away from unreacted DNA. Our results showed as the irradiation time increased, the absorption of free DNA decreased less in the presence of green tea, consistent with inhibition of DNA oxidation. In addition, agarose gel electrophoresis experiments of samples containing pUC19 DNA with tea that was stored at cold temperatures showed that the free DNA band persisted at dilutions of green tea up to 1:10000. While green tea was proven effective in purely chemical systems, the extent of antioxidative effects of green tea is studied in vivo studied in human melanoma cells (A375). A line of melanoma cells was cultured and propagated. By inducing oxidative damage with treatment and incubation for 4 hours of 200 μM H202, and preincubation for 4 hours with 1:10, 1:100, 1:1000 green tea:Dulbecco’s Modified Eagle Medium or water, effectiveness of green tea in preventing oxidative damage can be determined through Comet Assay analysis.

Summary of research results to be presented

Green tea exhibits antioxidative properties and has been show to reduce oxidative DNA damage including the prevention of DNA protein cross-linking with minimum concentrations of 1:10000.

This document is currently not available here.

Share

COinS
 
Nov 18th, 2:15 PM Nov 18th, 3:15 PM

Inhibition of DNA oxidative damage by green tea in vitro and in human melanoma cells

BSC-Ursa Minor 41

Oxidative damage is involved in the formation of free radicals, which can cause various diseases. Oxidation was effected by the flash-quench technique In our experiment, samples containing Ru(phen)2dppz2+(phen = 1,10-phenanthroline, dppz = dipyridophenazine), Co(NH3)5Cl2+, histone protein, calf thymus DNA and either water or green tea were irradiated for 0-4 minutes with 442 nm light from a HeCd laser to effect guanine damage. The extent of crosslinking was determined by the chloroform extraction assay, whereby protein and DNA-protein crosslink is extracted away from unreacted DNA. Our results showed as the irradiation time increased, the absorption of free DNA decreased less in the presence of green tea, consistent with inhibition of DNA oxidation. In addition, agarose gel electrophoresis experiments of samples containing pUC19 DNA with tea that was stored at cold temperatures showed that the free DNA band persisted at dilutions of green tea up to 1:10000. While green tea was proven effective in purely chemical systems, the extent of antioxidative effects of green tea is studied in vivo studied in human melanoma cells (A375). A line of melanoma cells was cultured and propagated. By inducing oxidative damage with treatment and incubation for 4 hours of 200 μM H202, and preincubation for 4 hours with 1:10, 1:100, 1:1000 green tea:Dulbecco’s Modified Eagle Medium or water, effectiveness of green tea in preventing oxidative damage can be determined through Comet Assay analysis.