Tohoku J. Exp. Med., 2004, 203(4)

The Effects of Hyperbaric Oxygen Treatment on Oxidant and Antioxidants Levels during Liver Regeneration in Rats

TÜLIN AYSE ÖZDEN, HAFIZE UZUN,¹ MEHRDAD BOHLOLI,² AKIN SAVAS TOKLU,³ MELIH PAKSOY,² GÖNÜL SIMSEK,⁴ HAYDAR DURAK,⁵ HALIM ISSEVER⁶ and TURGUT IPEK²

Institute of Child Health, Trace Element Unit, Istanbul University, Capa, Istanbul, Turkey,
¹Department of Biochemsitry, ²Department of General Surgery, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, ³Department of Underwater and Hyperbaric Medicine, Istanbul Medical Faculty, Istanbul University, ⁴Department of Physiology, ⁵Department of Pathology, Cerrahpasa Medical Faculty, ⁶Department of Public Health, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey

The effects of hyperbaric oxygen (HBO) therapy on oxidant/antioxidant metabolism are controversial and its effects on hepatic regeneration are not known. In this study, we investigated a possible beneficial effect of HBO therapy on oxidant and antioxidants levels during liver regeneration. To conduct this study, seventy percent hepatectomy was performed on forty-eight Spraggue-Dawley rats and the rats were divided into two equal groups: HBO-treated group and untreated group (non-HBO group). We determined the levels of malondialdehyde (MDA), an oxidative stress marker, and the levels of antioxidant enzymes/reagents, including glutathione (GSH), superoxide dismutase (SOD) activitiy, copper (Cu) and zinc (Zn), in the remnant liver samples. We also measured mitotic index (MI) and proliferating cell nuclear antigen (PCNA) levels to assess the degree of liver regeneration. HBO treatment significantly decreased MDA levels, whereas it increased SOD activity, GSH and Zn levels. In contrast, Cu levels were lower in the HBO-treated livers than the levels in the untreated remnant livers. The effect of HBO treatment may be mediated by the suppression of certain enzymes that are responsible for lipid peroxidation. In addition, HBO treatment may induce the production of antioxidant enzymes/reagents by remnant liver tissues. The HBO-treated rats maintained their body weights but the untreated rats lost body weights. HBO treatment also increased MI and PCNA levels, indicating HBO treatment enhances liver regeneration. These results indicate that HBO treatment has beneficial effects on liver regeneration by decreasing MDA and by increasing antioxidant activities. We therefore suggest that HBO therapy may be useful after liver resection.

keywords —— hyperbaric oxygen treatment; liver regeneration; oxidant; antioxidant; trace elements

© 2004 Tohoku University Medical Press

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Address for reprints: Tülin Ayse özden, Trace Element Unit, Istanbul University, Institute of Child Health, 34093, Capa, Istanbul, Turkey.

e-mail: tulozden@istanbul.edu.tr, tulnozden@yahoo.com