rn;
도꾀꾀alof Medici굶굶d Lif강Science Vol. 6. No. 5. 2009] Role of7
，
8-dihydroxyflavone on y- ray radiation-induced reactive oxygen speciesproduction
Rui Zhang
，
Kyoìmg Ah Kang，
and Jin Won HyunDepartment이B
∞
hemis!ry，Jeju NationalU미ver잉Iy SCh∞
1이Medicine.Jeμ Korea Abslracllonizing radiation can induce axidative stress through generation 01 reactive oxygen species (ROS).Flavonoids are a member
。
f polyphenolic compounds that occur in frui!s，vegetables，teas and red wines. 7，8-dihydroxy’
lavone‘a member of thef1avonoidgrouP. was elucidated the free radical scavenging effecl against y-ray radiation-induced ROS production. We found 7，
8-dihydroxyflavone 10 scavenge the inlracellular ROS delecled 씨h fluorescence speclrometer and llow cytom'etry (J Med Ufe
Sci 2009;6:365-367)
Key Words : 7，8--dihydroxyflavone，Reactive oxygen species，Flavonoids
Inlroduclion Malerials and melhods
」
2. Cell culture and irradialion
Fi밍lre 1. Chemical structure of 7.8-dihydroxyflavone 1. Reagents
깨e 7. 8-dihy이。xyflavone (Fig. 1) was fresh!y dissolved
in dimethyl sulfoxide (DMSOl. yielding a fmal conc밍ntr8tion， which did not ex
∞
ed 0.1%. 2’.7 ’-dichlor여l띠drofluorescein diacetate (DCF-DA) was purchased from the Sigma Chemical Company (St. Louis. MO. USA)O
ι-:/
、、
OH
HO
Chinese hamslßr lung fihroblasts (V79-4) cells from the Amencan Type Culture Collection (Rockville. MD. USAl were maint8ined at 37't in an Încubator with a humidified atmosphere of 5% Cα and cultured in Du!becco's modified Eagle’s medium，containing 10% heat-inactivated feta! calf serum ，streptomycin (100 pg/mI) .and penicillin (100 units/mD 끼113cells were exposed to Y-ray radation at 1.5 Gy/min from a ooCo y-ray source (MDS Nordion C-188
Address for correspondence : Jin WonHyUn
Depa끼menl 01BiochemistryMedìcine，Jeju NationalUniversily SChool이Medicine，66 Jejudaehakno，690-756，Jeju，Korea E--rr녕iI:jinwonh@jeiunu.ac.kr
Radiation ωxicity occurs either by direct attack on the genetic material and/or by generating reactive oxygen species (ROS) 5uch as superoxide 밍lion，hydrox:yl radical. and hydrogen peroxide by radiolysis of walerJl. These free radicals react with cellular macromolecules 5uch as DNA‘
proæin ，lipid membrane‘and cause cell dysfunction and m
。
πality2l，ROS mediated bimolecular reactions and theirrelationship with radiation sickness is the current suQject of scientific investigations in radiotherapy:n. Antioxidants are capable of scavenging free-radica!s from the radiolysis of water thereby protec니ng cell damage4l‘thus supplementation
。
f antiox:idants to improve the efficacy of radiotherapy is today' s proposed sσalßgy5'Flavonoids are a member of p。이)henolic compounds that
。
ccur in fruits. vegetables，teas and red wines6l. Several reports have been demonsσ'ated the relationship between structure and activity for. antioxidant properties of flavonoids7-9l.RecenUy we have reported the e.fTectof 7， 8-dihydroxyflavone on hydrogen peroxide-induced DNA damage and cell deathlOlπ
113present study investigated whether 7，8-dihydroxyflavone is capable of reducing Y-rBYradiation-induced ROS production in hamster lung fibroblast cells (V79-4)RuiZhang.KyoungAh Kang.Jin WonHyun
standard source‘J~u National Universitr，J밍U‘Korea)
3. Inlracellular reaclive oxygen species (ROS) measurement
π113 V79-4 cells were σ.•aled with 7. 8-dihydroxyflavone at 10 밍I띠 and were cxposed ω y-.ray radiation an hour later. T↑113cells were incubated for an additional 24 h at 37
t. Afler adding 25 M of DCF-DA solution‘the nuorescence of 2'‘7’dichloronuorescein was detected using a Perkin
Elmer LS-5B spectronuorometer and a flow cytometer (Becton Dickinson. Mountain View‘CA. USA)，respectivelyl1l
4，Slalislical analysis
All measurements were made ìn triplicate 어1d all values
were expressed as the means :!::: standard error of the mean (S.E.M.). The results were subjected to an analysis of variance (ANOVA) using the 1'ukey test to analyze the difference. P ( 0‘05 was considered significantly
0
0
0 5 '0 15 20Gy
Figure 3. Effect of 7.8-dihydroxyf1avone on scavenging intracellular ROS generated by y-ray irradiation at 10 Gy
깨e V79-4 cells were treated with.7.8-dihydroxyflavone at 10 μg/ml ，followed by y-ray irradiation at 10 Gy an hour later. Next. the cells were incubated for 48h‘the
intracel1ular ROS was detected using flow cytometer after DCF-DA staining
Con'rnl FI: 146
10Gy
"‘，.
7，6깅îhydro여avone+10Gy
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t
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•References
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