Gut Liver.  2011 Dec;5(4):486-492.

Role of UCP2 Expression after Hepatic Warm Ischemia-Reperfusion in the Rat

• Ninomiya M
• Shirabe K
• Shimada M
• Terashi T
• Maehara Y

Abstract

BACKGROUND/AIMS
The role of uncoupling protein-2 (UCP2) in the liver is currently unclear. Emerging evidence suggests a relationship between UCP2 and oxidative stress. In the present study, we tested the hypothesis that UCP2 expression in the liver might change during warm ischemia-reperfusion (I/R) according to oxidative stress.
METHODS
Wistar rats were subjected to 40 (short ischemia) or 90 (long ischemia) minutes of partial lobar ischemia followed by 4 hours of reperfusion. UCP2 expression in the ischemic and nonischemic lobes was assessed using reverse transcription-polymerase chain reaction and immunohistochemistry. Malondialdehyde concentrations in the liver tissue were also compared.
RESULTS
Malondialdehyde concentrations in the ischemic lobes were significantly higher in the long ischemia group. In the ischemic lobes of the short ischemia group, UCP2 protein expression was induced in hepatocytes, which did not express the protein prior to treatment, and the expression levels were higher than in the long ischemia group. The intralobular distribution of UCP2 seemed to correlate inversely with that of the necrotic area. UCP2 expression was observed, even in nonischemic lobes with similar intralobular heterogeneity.
CONCLUSIONS
UCP2 was induced in hepatocytes after warm I/R. Although the primitive role of UCP2 expression may be cytoprotective in nature, its actual protective effect in hepatic I/R may be minimal

Keyword

Oxidative stress; Ischemia-reperfusion; Uncoupling protein; Liver; Surgery

MeSH Terms

Animals
Hepatocytes
Immunohistochemistry
Ion Channels
Ischemia
Liver
Malondialdehyde
Mitochondrial Proteins
Oxidative Stress
Rats
Rats, Wistar
Reperfusion
Ion Channels
Malondialdehyde
Mitochondrial Proteins