Effects of repeated desflurane and sevoflurane anesthesia on enzymatic free radical scavanger system

Similarity and dissimilarity in alterations of the gene expression profile associated with inhalational anesthesia between sevoflurane and desflurane

Although sevoflurane is one of the most commonly used inhalational anesthetic agents, the popularity of desflurane is increasing to a level similar to that of sevoflurane. Inhalational anesthesia generally activates and represses the expression of genes related to xenobiotic metabolism and immune response, respectively. However, there has been no comprehensive comparison of the effects of sevoflurane and desflurane on the expression of these genes. Thus, we used a next-generation sequencing method to compare alterations in the global gene expression profiles in the livers of rats subjected to inhalational anesthesia by sevoflurane or desflurane. Our bioinformatics analyses revealed that sevoflurane and, to a greater extent, desflurane significantly activated genes related to xenobiotic metabolism. Our analyses also revealed that both anesthetic agents, especially sevoflurane, downregulated many genes related to immune response.

Association between genotoxic properties of inhalation anesthetics and oxidative stress biomarkers

Exposure to inhalation anesthetics (IAs) has been associated with DNA damage as reflected in the increased frequency of micronuclei (MN) and chromosomal aberrations (CAs). The present study was undertaken to ascertain whether there was any correlation between increased MN and CA and the extent of oxidative stress as well as the antioxidant status of a group of operating room personnel exposed to a mixture of IAs, including nitrous oxide, isoflurane, and sevoflurane. In this cross-sectional study, 60 operating room personnel (exposed group) in whom the frequencies of MN and CA had already been shown to be significantly higher than those of a referent group, as well as 60 unexposed nurses, were studied. Venous blood samples were taken from all participants, and malondialdehyde (MDA) levels as an index of oxidative stress (OS) and the activity of superoxide dismutase (SOD) and levels of total antioxidant capacity (TAC) as indices of antioxidant status were measured. The level of TAC (1.76 ± 0.59 mM vs. 2.13 ± 0.64 mM, p = 0.001) and the activity of SOD (11.22 ± 5.11 U/ml vs. 13.36 ± 4.12 U/ml, p = 0.01) were significantly lower, while the mean value of MDA was significantly higher (2.46 ± 0.66 µM vs. 2.19 ± 0.68 µM, p = 0.03) in the exposed group than in the nonexposed group. After adjusting for potential confounders, there were statistically significant associations between exposure to IAs, gender, SOD, and TAC with MN frequency and between exposure to IAs and SOD with numbers of CA. The findings of the present study indicated that exposure to IAs was associated with OS, and this, in turn, may be causally linked with DNA damage.

Interaction of diesel exhaust particles with human, rat and mouse erythrocytes in vitro

Inhaled ultrafine (nano) particles can translocate into the bloodstream and interact with circulatory cells causing systemic and cardiovascular events. To gain more insight into this potential mechanism, we studied the interaction of diesel exhaust particles (DEP) with human, rat and mouse erythrocytes in vitro. Incubation of erythrocytes with DEP (1, 10 or 100 μg/ml) for 30 min caused the highest hemolytic effect (up to 38%) in rats, compared to small but significant hemolysis in mice (up to 2.5%) and humans (up to 0.7%). Transmission electron microscopy of erythrocytes revealed the presence of variable degrees of ultrafine (nano)-sized aggregates of DEP either internalized and/or adsorbed onto the erythrocytes in the three species. A significant amount of DEP was found in rat and mouse (but not human) erythrocytes. Lipid erythrocyte susceptibility to in vitro peroxidation measured by malondialdehyde showed a significant and dose-dependent increase in erythrocytes of rats, but not humans or mice. Unlike in human erythrocytes, total antioxidant status (TAS) and superoxide dismutase (SOD) activity in rats were significantly and dose- dependently decreased. In mouse erythrocytes, DEP caused a decreased in SOD (at 10 μg/ml) and TAS (at 100 μg/ml) activities. In conclusion, DEP caused species-dependent erythrocyte hemolysis and oxidative stress, and were either taken up and/or adsorbed onto the red blood cells. Rat (and to a lesser degree mouse) erythrocytes were susceptible to DEP. Human erythrocytes showed the highest resistance to the observed effects. These species difference should be noted when using rats and mice blood as models for humans.

Effects of vitamin C and E combination on element and oxidative stress levels in the blood of operative patients under desflurane anesthesia

We investigated effects of vitamin C and E (VCE) administration on desflurane-induced oxidative toxicity and element changes in the blood of operative patients under desflurane general anesthesia. Forty American Society of Anesthesiologists I or II Physical Status adult patients were scheduled for elective surgery. The patients were randomly divided into two groups. Control and VCE group was introduced to anesthesia with desflurane. VCE was administreted to patients in the control and VCE group before 1 hour of anesthesia with desflurane. Baseline (preoperative) and postoperative (at the 1(st), the 24(th), and 72(th) h), blood samples were taken from the first and second groups. Erythrocyte and plasma lipid peroxidation levels at the 1(st), 24(th), and 72(th) hours were higher in the control than in baseline group, although their levels at the same periods were lower in the VCE group than in the control. Vitamin E levels at the postoperative 1(st) and 24(th) hours and erythrocyte glutathione peroxidase (GSH-Px) activity at the postoperative 1(st), 24(th), and 72(th) hours was lower than in baseline values. Erythrocyte GSH-Px activity and plasma vitamins A, C, and E levels at the postoperative 1(st), 24(th), and 72(th) hours were higher in the VCE group than in the control group. Erythrocyte and plasma reduced glutathione, plasma β-carotene, and serum copper, while zinc, selenium, aluminum, iron, magnesium, and calcium levels did not differ between preoperative and postoperative periods in both groups. In conclusion, VCE combination prevented the desflurane-induced vitamin E and GSH-Px consumptions to strengthen the antioxidant levels in the blood of operative patients.

Evaluation of antioxidant parameters in rats treated with sevoflurane

BACKGROUND AND OBJECTIVES

Sevoflurane is a halogenated fluorinated ether that undergoes hepatic biotransformation through cytochrome P4502E1. Halogenated ethers undergoing biotransformation by P4502E1 can produce reactive oxygen species (ROS), weakening the antioxidant defense mechanism. The objective of this study was to investigate the relationship between the activity of erythrocyte antioxidant enzymes and sevoflurane.

METHODS

Animals were divided in four groups: Group 1 - control: 100% oxygen (1 L.min(-1) for 60 min during five consecutive days); Group 2 - 4.0% sevoflurane in 100% oxygen (1 L.min(-1) for 60 minutes during five consecutive days); Group 3 - isoniazid (i.p.), 50 mg.kg(-1)/ day for four consecutive days, followed by 100% oxygen (1 L.min(-1) for 60 minutes during four consecutive days); Group 4 - intraperitoneal isoniazid, 50 mg.kg(-1) daily for four days, followed by 4.0% sevoflurane in 100% oxygen (1 L.min(-1) for 60 minutes during five days). Twelve hours after the last exposure to sevoflurane, animals were sacrificed and their blood was collected through the portal vein for analysis of antioxidant enzymes.

RESULTS

An increase in the activity of glucose-6-phosphate dehydrogenase and a decrease in the activity of catalase were observed, especially in the group of animals pre-treated with isoniazid. Changes in the activity of glutathione peroxidase were not observed.

CONCLUSIONS

The interaction between sevoflurane and cytochrome P450 2E1 with enzymatic inducers can lead to oxidative stress with prolonged and repetitive exposure.

Sevoflurane hepatotoxicity: a case report of sevoflurane hepatic necrosis and review of the literature

Sevoflurane, a halogenated anesthetic, is associated with mild aminotransferase elevations but does not tend to cause clinically significant hepatotoxicity. We report a rare case of severe hepatic necrosis following exposure to sevoflurane during surgery. A 37-year-old man presented with nausea,vomiting, abdominal pain, and jaundice on the third postoperative day after an abdominal wall mass resection. Laboratory tests showed markedly elevated aminotransferase levels, hyperbilirubinemia, and coagulopathy. His viral hepatitis and human immunodeficiency virus (HIV) serologies were negative for acute infection, and his Epstein-Barr virus (EBV) and cytomegalovirus (CMV) serologies were suggestive of recent EBV infection and remote CMV infection. Antinuclear antibody and anti-smooth muscle antibody screens were negative. Ceruloplasmin and serum copper values were in the normal range. The histopathological findings included an acute centrilobular cholestatic hepatocellular injury compatible with the clinical history of acute drug-induced hepatotoxicity. The patient improved with conservative management. Unlike other halogenated anesthetics, proposed mechanisms of sevoflurane hepatotoxicity include production of compound A, increased cytosolic free Ca(2+), and activation of free radical metabolizing enzymes. The patient was likely susceptible to toxicity due to an underlying EBV infection and a probable history of exposure to halogenated anesthetics. Sevoflurane is generally considered to be relatively safe for subjects with mild liver dysfunction, in comparison with other halogenated anesthetics. However, this case suggests that sevoflurane can lead to severe life-threatening hepatic necrosis in at-risk individuals.