In vitro exposure to carbon dioxide induces oxidative stress in human peritoneal mesothelial cells.
BACKGROUND
The objective of this study was to verify whether in vitro exposure of human peritoneal mesothelial cells to carbon dioxide (CO(2)) influences the levels of 8-isoprostaglandin F(2alpha) (8-iso-PGF(2alpha)), a marker of oxidative stress.


METHODS
Mesothelial cells were exposed to either: (i). 100% CO(2) for 4 h; (ii). 100% helium (an alternative gas with which to create hypoxic conditions) for 4 h; (iii). 100% CO(2) for 24 h; or (iv). standard conditions (control). After gas exposure, mesothelial cells were returned to standard conditions and harvested immediately (T(0)), and at 1-(T(1)) and 3 (T(3)) h afterwards. Cell viability and culture medium pH were monitored throughout the experiments. 8-iso-PGF(2alpha) was assayed by enzyme-linked immunosorbent assay (ELISA).


RESULTS
Exposure to CO(2) decreased the culture medium pH whereas helium increased the pH. 8-iso-PGF(2alpha) levels in all treated groups were significantly higher than in the control group: in the 4 h CO(2) group at T(1); in the 24 h CO(2) group at T(0) and T(1); and in the 4 h helium group at T(0), T(1) and T(3). 8-iso-PGF(2alpha) levels following 4 h CO(2) exposure were significantly lower than after 24 h CO(2) exposure at T(1), and lower than following 4 h helium exposure at all time points.


CONCLUSIONS
Exposure to both CO(2) and helium induces oxidative stress in mesothelial cells. Hypoxia-reoxygenation may play a role in this process.
Bentes de Souza
Angela M
AM
Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR.
Wang
Chi Chiu
CC
Chu
Ching Yan
CY
Briton-Jones
Christine M
CM
Haines
Christopher J
CJ
Rogers
Michael Scott
MS
D000328:Adult; D002245:Carbon Dioxide / Q000494:pharmacology*; D002478:Cells, Cultured; D003470:Culture Media / Q000737:chemistry; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D005260:Female; D006371:Helium / Q000494:pharmacology; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D018384:Oxidative Stress; D010537:Peritoneum / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*
D003470:Culture Media; D002245:Carbon Dioxide; D006371:Helium; C075750:8-epi-prostaglandin F2alpha; D015237:Dinoprost