An inter-laboratory validation of methods of lipid peroxidation measurement in UVA-treated human plasma samples

Abstract

Lipid peroxidation products like malondialdehyde, 4-hydroxynonenal and F₂-isoprostanes are widely used as markers of oxidative stress in vitro and in vivo. This study reports the results of a multi-laboratory validation study by COST Action B35 to assess inter-laboratory and intra-laboratory variation in the measurement of lipid peroxidation. Human plasma samples were exposed to UVA irradiation at different doses (0, 15 J, 20 J), encoded and shipped to 15 laboratories, where analyses of malondialdehyde, 4-hydroxynonenal and isoprostanes were conducted. The results demonstrate a low within-day-variation and a good correlation of results observed on two different days. However, high coefficients of variation were observed between the laboratories. Malondialdehyde determined by HPLC was found to be the most sensitive and reproducible lipid peroxidation product in plasma upon UVA treatment. It is concluded that measurement of malondialdehyde by HPLC has good analytical validity for inter-laboratory studies on lipid peroxidation in human EDTA-plasma samples, although it is acknowledged that this may not translate to biological validity.

Keywords::

• Oxidative stress
• F2-isoprostanes
• 4-hydroxynonenal
• malondialdehyde

Acknowledgements

All the authors would like to acknowledge the support of B35 COST Action on Lipid Peroxidation Associated Disorders. CMS acknowledges a PhD studentship from the Malaysian Government for NMF. NZ, LA, SB and LM acknowledge support from the Croatian Ministry of Science, Education and Sports. GB, JD, AG and PS thank 83/N-Cost/2007/0 grant-in-aid for support. RC thanks ISC III (Thematic Network RD06/0045) for financial support; MTM and IC are grateful for support from Grups de Recerca Consolidats 2009/SGR438 of the Generalitat de Catalunya. LB and RM acknowledge financial support from the Spanish Ministry of Science and Innovation for Projects AGL2007-64042 and CSD2007-00063. GP and FB acknowledge the Ministry of University, Rome, Italy, PRIN 2007 project and the Region of Piedmont, Italy, ‘Ricerca Sanitaria Finalizzata’ projects 2008 and 2009. MA acknowledges grants from the Finnish Ministry of Education and thanks Taina Vihavainen for providing technical assistance.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This paper was first published online on Early online on 23 July 2010.