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Published on: June 7, 2020
Comparison of estrogen and genistein in their antigenotoxic effects, apoptosis and signal transduction protein
1Department of Food and Nutrition, Hannam University, 133 Ojeong-dong Daedeok-gu, Daejeon 306-791, Korea. ojpark@hannam.ac.kr
Abstract:
The antigenotoxic effects of estrogen and genistein (isoflavones) were compared by measuring the degree of protection against plasmid DNA strand breakage induced by peroxyl free radicals using the DNA strand scission assay with pBR322 DNA. Isoflavones decreased DNA strand breakage by AAPH radical treatment at the all of three concentrations tested (0.5, 1.0, 1.5 microg/ml) with the range of 89.5% to 99.6%. Compared to genistein, estrogen was not as effective as genistein showing 46.9% to 29.6% protection, and this protective effect was decreased as estrogen concentrations increased from 0.1 to 0.3 microg/ml. DNA ladder experiments showed that genistein induced apoptosis in cultured cell lines, whereas estrogen did not induce any apoptosis. The effects of cell signal trandsduction protein expression patterns were compared between estrogen and genistein. The increased expression of cyclin B1 by estrogen was tampered by genistein at the highest concentration. Antigenotoxic and antiproliferative effects of genistein shown in this study support the hypothesis that it has a chemopreventive effect against particular types of cancers.
Insights
Genistein, a soy isoflavone, demonstrated potent antigenotoxic effects, significantly protecting DNA from damage. Unlike estrogen, genistein also induced apoptosis, suggesting potential cancer chemopreventive properties.
Area of Science:
- Molecular Biology
- Biochemistry
- Genetics
Background:
- Estrogen and genistein (isoflavones) are compounds with known biological activities.
- DNA damage from free radicals is implicated in various diseases, including cancer.
- Understanding the comparative effects of these compounds on DNA integrity is crucial.
Purpose of the Study:
- To compare the antigenotoxic effects of estrogen and genistein against peroxyl free radical-induced DNA strand breakage.
- To investigate the impact of genistein and estrogen on apoptosis and cell signaling pathways.
- To evaluate the potential chemopreventive role of genistein.
Main Methods:
- DNA strand scission assay using pBR322 DNA to measure protection against AAPH radical-induced damage.
- DNA ladder experiments to assess apoptosis induction.
- Comparison of cell signal transduction protein expression patterns.
Main Results:
- Genistein exhibited significant antigenotoxic effects, reducing DNA strand breakage by 89.5% to 99.6% across tested concentrations.
- Estrogen showed less effective DNA protection (29.6% to 46.9%), with decreased efficacy at higher concentrations.
- Genistein induced apoptosis in cell lines, while estrogen did not; genistein also modulated cyclin B1 expression influenced by estrogen.
Conclusions:
- Genistein possesses strong antigenotoxic and antiproliferative properties, supporting its potential as a chemopreventive agent against certain cancers.
- Genistein's ability to induce apoptosis and modulate cell signaling pathways differs from estrogen's effects.
- These findings highlight genistein's distinct biological activities compared to estrogen in the context of DNA protection and cell fate.
