Nuclear factor-ĸB (NFĸB) is a pleiotropic transcriptional activator, which is a sensitive transcriptional factor for free radicals and activates multiple target genes. UVA is very efficient in inducing free radicals in human skin cells. L-ascorbic acid is regarded as a scavenger of UVA-induced free radicals in human keratinocytes. In epidermis, melanocytes and keratinocytes play an important protective role against skin photodamage. In the present study, we aimed to investigate the role of NFĸB on photodamage in melanocytes and keratinocytes. Normal human melanocytes (NHM) and HaCaT keratinocytes were treated with UVA (500 mJ/cm², 1,000 mJ/cm2) and/or L-ascorbic acid (100 µM, 250 µM). NFĸB binding activity was analysed by electrophoretic mobility shift assay. NFĸB binding activity was increased by UVA irradiation in HaCaT keratinocytes, but it was not affected in NHM. On the other hand, L-ascorbic acid decreased NFĸB binding activity both in UVA-irradiated and in non-irradiated NHM. In contrast, NFĸB binding activity in HaCaT keratinocytes was increased after treatment with L-ascorbic acid. In addition, L-ascorbic acid synergistically induced NFĸB binding activity with UVA irradiation. The contrary response on NFĸB binding activity in NHM and HaCaT keratinocytes indicated that the redox regulation might be different on photoprotective action in melanocytes and keratinocytes.

Keywords:
Nuclear factor-ĸB, Melanocytes, Keratinocytes, UVA, L-ascorbic acid
This content is only available via PDF.
© 2002 S. Karger AG, Basel
2002
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.