148 Role of singlet oxygen in hydrogen peroxide production in riboflavin solution irradiated by UVA under different oxygen concentration

206

JSID Abstracts

148 ROLE OF SINGLET OXYGEN IN HYDROGEN PEROXIDE PRODUCTION IN RIBOFLAVIN SOLUTION IRRADIATED BY UVA UNDER DIFFERENT OXYGEN CONCENTRATION. H. Minami*‘*2, K. Sa&, H. Taguchil. T. Maedal, and T. Tsuji2. De artmems of Dermatology, IOsaka 5 University School of Medicine, Osaka, Nagoya City University Medical School, Nagoya. Japan. When riboflavin solution is irradiated with UVA, it produces cytotoxicity. Almost all of the long-lived cytoroxicity is due to hydrogen peroxide produced in the solution. The production of hydrogen peroxide is faster under low oxygen conditions than under aerobic ones. We examined the possibility that singlet oxygen has some role in the production of hydrogen peroxide under our UVA-irradiation conditions. Because sodium azide is s scavenger of singlet oxygen. it was added to riboflavin solution during UVAirradiation and the cytotoxicity of the solution was tested with the colony formation of fibroblasts treated with the solution. By the addition of sodium snide, the cytomxicity of UVA-irradiated riboflavin solution decreased to the same level in either case of oxygen condition. This result indicates that singlet oxygen played a role in producing hydrogen peroxide in UVAirradiated riboflavin solution and that under low oxygen conditions hydrogen peroxide was produced from singlet oxygen faster.

146

149

INHIBrORY EFFECTS OF AU’INIA SPECIASA ON PORPHYRIN PHOTOTOXIC REACTION. M.C.Llaol.H.Arakakl* ms S.Nonab’.’ Department of Dermatdogy. Faculty of Medlclne.Unlversltu0f the Ryuk~~9. OKINAWA. JAPAN. 3 collage of Asriculture,Unlverslty of the Ryukyus.OlUNAWA.JAPAN.’ Department ofAnalytlcalChemlstry., ~r%o&armacentlcal Unlvers&.KyotoJAPAN. The causes of photo-dennatoses are attributable to phototoxic reactIons orpho&allerglc reactlons. Phototoxlc reactIons have been reported In Dorphyrlc patients and many drug Induced photosensltlzatlon. B-carotene Is the most popular protective agent In pomhyrln phototoxlhr. In order to search for agents which have the same effects as P-carotene. We used an experiment al method deslgned to measure the formatIon of LPO. LP0 was formed by lrradlatlna with light on solution of uor&rlnmlcrceome. We added different concentrations of All9nla Speclasa (S.A.) extract solution In thlsexwrlment to see If LP0 farnatIon suppressed. A.S.dld Indeed lnhlblt the formation of LP0. as weU as slnglet oxygen. The latter was determlned by the ES&In trap method. A component and Its derlratlves of A.S. showed powerful ablllty to inhlblt sin&et oween.

CMOTOXITY OF TWO SUBSTANCES WHITCH WERE ELUTED BY HPLC FROM UVA-IRRADIATED PYRIDOXINE. H. Taguchi’, T. Maeda’,

H.

Osaka

‘Department Nagoya,

Pyridoxine

is thought of the skin

irradiated

pyridoxine

K.

Yosikawa’

School Nagoya

. ‘Department

of Medicine,

City

Osaka,

University

solution.

to be a possible because

of Japan.

Medical

and have

different

the cytotoxicity

150

CROSS-REACTIVITY OF QUINOLONES IN T-CELL RESPONSES % QUINOLONE-PHOTOMODIFIED CELLS. y. Tokura. H. Yani. T. Furuka a. M. Takim Department of Dermatology, Hamamatsu lJniversity%hool of Medici& Hamamatsu, Japan. photoallergenicity of tluoroquinolones (FQs), we To address examined the photohaptenic potential of FQs in mice. Because of the ability of FQs to photobind to protein, murine epidermal cells were easily modified with FQs by exposure to UVA. Subcutaneous inoculation of FQphotomoditied epidermal cells succesfully induced and elicited a delayedtype hypersensitivity in mice. Immune lymph node calls from FQ-sensitized mice proliferated well in v&o to FQ-photomodified Langerhans cellenriched epidermal cells. In this in vitro system, lomefloxacin. ciprofloxacin and nortloxacin had high abilities to sensitize mice. Immune ly&ph node cells of lomefloxacin, ci$floxacin and norfloxacin responded well not onlv 10 Laneerhans cells &otomodit%d with the comsoondinn FO but also to ihosc ph&derivat&d with other FQs, suggesting that b;oai photoantigenic cross-reactivity exists among FQs. This cross-reactivity was also evidenced by the finding that CD4+ T cell populations that expanded after in vitro photoantigenic stimulation of lomefloxacin-, ciprotloxacin-

EVALUATION ALA

were

by HPLC showen

mass number

examined

patterns

in vitro

We Presented

were eluted

The substances

same maximum

chromophore

of strong

solution.

that two substances

147

and norfloxacin-lymph node cells expressed the same VP13 of T-cell receptor. These findings demonstrated that FQs are photohaptens with bmad potential crossing-photoantigenicity.

Sate’,

of Dermatology,

photoaging

WITH

K. University

School,

Japan.

27 min with

the

Minami’,

Dermatology,

responsible

cytotoxicity

in the latest

annual

from WA-irradiated

of smaller

is equal

masses.

meeting pyridoxine

by mass spectrography

164, which

to have the

to that of pyridoxine,

In the pmsent

of the two substances

study,

that were elutcd

OF THE

EFFECT

M.Yanatiha&.

K.&da!.

Dermatology.

&panment

OF PHOTODYNAMIC

BY NMR

THERAPY

SPECTROSCOPY.

N.Mivash?

K.lshi~~ro~~

and M.Fukudkz

of Pathology.

Fukui

‘Ocpartmnt

Medical

Sch&l,

of Fukui,

Japan. In viva

“P-NMR

spcctm were obtained

skin cancer in C3H Aminolevulinic

Acid Hydrochloride

photodynamic marked

inhibition

therapy

increase

was consided of

with

ALA.

(ALA)

mitocontialfunction.

with

compared

coil method

and without

lmmediiely

a rapid decrease

in Pi were observed that the reduction

tissue to ALA-induced

by a surfase

mice after laser irradiation

with

was a early

photosensitization.

from

5-

aftm

in ATP levels and a inadiation

of ATP levels in tumor, response

we

at 21 and

HPLC.

MONITORED

for

of LIVA-

alonc.lt

probably of neopla&

via