* β-Naphthoflavone induces oxidative stress in the intertidal copepod, Tigriopus japonicus.
- β-Naphtoflavone (β-NF) is a flavonoid and enhances oxidative stress in vertebrates with little information from aquatic invertebrates as yet. In this study, we investigated the effects of β-NF on the antioxidant defense systems of the intertidal copepod Tigriopus japonicus. To measure the β-NF-triggered changes in oxidative stress markers, such as intracellular reactive oxygen species (ROS), glutathione (GSH) concentration, residual glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR), and superoxide dismutase (SOD) activity, T. japonicus were exposed to β-NF (0.5 and 1 mg/L) for 72 h. Significant (P < 0.05) induction of the intracellular ROS content (%) was observed in 1 mg/L of β-NF exposed T. japonicus, compared to the negative control and H2O2-exposed group. The GSH levels were significantly increased in the 0.5 mg/L of β-NF-exposed group for 12 h and 1 mg/L of β-NF-exposed groups for 12-24 h. GPx, GST, and GR activities showed a significant increase in the 1 mg/L β-NF-exposed group, indicating that β-NF induces oxidative stress in T. japonicus. To understand the effects of β-NF at the level of transcript expression, a 6K microarray analysis was employed. Transcript profiles of selected antioxidant-related genes were modulated after 72 h exposure to 1 mg/L of β-NF. From microarray data, 10 GST isoforms, GR, GPx, PH-GPx, and Se-GPx were chosen for a time-course test by real-time RT-PCR. T. japonicus GST-S, GST-O, GST-M, and GST-D1 were significantly increased in a 1 mg/L β-NF-exposed group. T. japonicus GPx, GR, and Se-GPx mRNA levels were also significantly increased at both concentrations. Our results revealed that oxidative stress was induced by β-NF exposure in T. japonicus.
=>1.時代, 季節, 歳月, 当時, 現代, 一生, 年季, 就業時間, 期間, 時刻, 時点, 機会, 拍子, 速度, 何度, 何回,
時, 時間, 回, 2.時間[速度]を測定する, 時間を決める, (装置などの)タイミングを調節する
Overview of noun time
The noun time has 10 senses (first 9 from tagged texts)
1. (219) time, clip -- (an instance or single occasion for some event; "this time he succeeded"; "he
called four times"; "he could do ten at a clip")
2. (160) time -- (a period of time considered as a resource under your control and sufficient to
accomplish something; "take time to smell the roses"; "I didn't have time to finish"; "it took more
than half my time")
3. (114) time -- (an indefinite period (usually marked by specific attributes or activities); "he
waited a long time"; "the time of year for planting"; "he was a great actor in his time")
4. (43) time -- (a suitable moment; "it is time to go")
5. (36) time -- (the continuum of experience in which events pass from the future through the
present to the past)
6. (10) time -- (a person's experience on a particular occasion; "he had a time holding back the
tears"; "they had a good time together")
7. (7) clock time, time -- (a reading of a point in time as given by a clock; "do you know what time
it is?"; "the time is 10 o'clock")
8. (5) fourth dimension, time -- (the fourth coordinate that is required (along with three spatial
dimensions) to specify a physical event)
9. (1) meter, metre, time -- (rhythm as given by division into parts of equal duration)
10. prison term, sentence, time -- (the period of time a prisoner is imprisoned; "he served a prison
term of 15 months"; "his sentence was 5 to 10 years"; "he is doing time in the county jail")
Overview of verb time
The verb time has 5 senses (first 3 from tagged texts)
1. (4) clock, time -- (measure the time or duration of an event or action or the person who performs
an action in a certain period of time; "he clocked the runners")
2. (3) time -- (assign a time for an activity or event; "The candidate carefully timed his
appearance at the disaster scene")
3. (1) time -- (set the speed, duration, or execution of; "we time the process to manufacture our
cars very precisely")
4. time -- (regulate or set the time of; "time the clock")
5. time -- (adjust so that a force is applied and an action occurs at the desired time; "The good
player times his swing so as to hit the ball squarely")
--- WordNet end ---