Hyperbaric oxygen therapy and ischemia and reperfusion: a valuable association to attenuate ischemic lesion and hepatic reperfusion

Abstract

PURPOSE:To investigate the consequences of the association between hyperbaric oxygen therapy and hepatic ischemia / reperfusion. METHODS:Wistar rats were divided into three groups: SHAM, rats submitted to surgical stress and anesthetic but not hepatic ischemia or reperfusion, I / R, rats submitted to total hepatic pedicle ischemia for 30 min, followed by 5 min of reperfusion; HBO120, rats submitted to 120 min of hyperbaric oxygen therapy at two absolute atmospheres and immediately after submitted to the experimental protocol of ischemia and reperfusion. The preservation of the hepatic function was evaluated by determining mitochondrial swelling and malondialdehyde tissue level, as well as alanine aminotransferase and aspartate aminotranferase serum levels. The results were analyzed using the Mann-Whitney test and differences were considered significant for p<0.05. RESULTS:There were significant differences in values: mitochondrial swelling of the I / R group compared to SHAM and HBO120; malondialdehyde between SHAM vs. I / R, SHAM vs HBO120, and I / R vs HBO120, alanine aminotransferase between SHAM vs. I / R . There was no significant difference between groups in aspartate aminotransferase serum levels. CONCLUSION:The association between hyperbaric oxygen therapy and hepatic ischemia and reperfusion process was positive.

Effects of hyperbaric oxygen therapy on the liver after injury caused by the hepatic ischemia-reperfusion process

“…Although expected, no difference was observed with HBO. This fact was not observed in other studies, in which the SHAM and IR groups already presented some difference [10][11][12]16 . In those studies there was an increase in the rate of oxygen consumption by the mitochondria compared to the SHAM group in order to maintain the electrochemical proton gradient on the mitochondrial membrane so that the membrane would be able to phosphorylate ADP 16,17 .…”

“…This complex that affects the liver in various surgical procedures such as liver transplantation 15 is being investigated in order to find some way of attenuating its adverse effects. In an attempt to contribute to a greater number of possibilities for the attenuation of the undesirable effects of the procedure, we performed the surgical procedure of hepatic I/R followed by submission of the experimental animals to high oxygen pressures in a hyperbaric chamber 10,12,16 In the present study, the production of energy by the mitochondria was analyzed starting from State 3. Regarding this analysis, we may state that the animals submitted to HBO after hepatic I/R showed an improvement when compared to the rats submitted only to I/R.…”

Hyperoxic preconditioning in partial liver ischemia

“…This result is found by other authors 12,13 , but in different models of ischemia-reperfusion. Taking into consideration the oxygen consumption in stage 3 it was not found in our study significant difference between the group that underwent ischemia and, reperfusion with or without exposure to HBO, demonstrating that HBO was not harmful when this parameter was evaluated.…”

“…Oxygen 100% was used in all groups of HBO treatment. The chamber was gradually compressed and decompressed at 1.3 ATA/min for 15 minutes each, which was not considered as treatment time 7,13 .…”

Effect of irradiation with different laser wavelengths on oxidative stress of non-hepatectomized rats

“…The main objective was to determine the effect of laser light on hepatic energy capacity based on previous studies from our laboratory about hepatic function and mitochondrial function 5,18,19 . The liver, as matter in its nature, consists of atoms that form molecules, structures, tissues, organs and organisms.…”