Biomedical subjects

Ewa Macierzyńska

Publications and source records attributed to Ewa Macierzyńska.

2 recordsLinked to original sources

PubMed2006

Accumulation of oxidative damage during replicative aging of the yeast Saccharomyces cerevisiae.

Comparison of senescent yeast obtained by the "baby machine" technique with 2-day-old stationary phase cells revealed decreased activities of glutathione reductase, glutathione S-transferase, glutathione peroxidase and alcohol dehydrogenase, reduction of total antioxidant capacity, protein glycation and accumulation of products of oxidative damage: protein carbonyls and DNA damage assessed by augmented content of 8-oxoguanine and increased tail momentum of cellular DNA in the comet assay. These results are consistent with a role for oxidative damage during replicative senescence of Saccharomyces cerevisiae.

Antioxidants↗

PubMed2004

Melatonin does not react rapidly with hydrogen peroxide.

It has been claimed that melatonin reacts directly with hydrogen peroxide with a very high rate constant (2.5 x 10(5)-2.3 x 10(6) M(-1) s(-1)) Both these values were derived from inhibition by melatonin of peroxidase-catalyzed oxidation of Phenol Red by hydrogen peroxide, assuming that this inhibition is due to direct scavenging of hydrogen peroxide by melatonin. In this study, we show that this reasoning is illegitimate and melatonin decreases the yield of oxidation of Phenol Red as a competitive substrate. Monitoring changes of concentration of hydrogen peroxide incubated with melatonin using Xylenol Orange points to poor reactivity of melatonin with H2O2.

Chromans↗