Effect of Hepatic Preconditioning with the Use of Methylene Blue on the Liver of Wistar Rats Submitted to Ischemia and Reperfusion.

BACKGROUND: The liver may be injured in situations where it is submitted to ischemia, such as partial hepatectomy and liver transplantation. In all cases, ischemia is followed by reperfusion and, although it is essential for the reestablishment of tissue function, reperfusion may cause greater damage than ischemia, an injury characterized as ischemia-reperfusion (I/R) damage. The aim of this work was to analyze the effect of ischemic preconditioning with the use of methylene blue (MB; 15 mg/kg) 5 or 15 minutes before I/R (IRMB5' and IRMB15', respectively) on the hepatic injury occurring after I/R. METHODS: Twenty-eight male Wistar rats were used, and liver samples submitted to partial ischemia (IR) or not (NI) were obtained from the same animal. The samples were divided into 7 groups. Data were analyzed statistically by means of the nonparametric Mann-Whitney test and Wilcoxon Matched test, with the level of significance set at 5% (P < .05). RESULTS: The rate of oxygen consumption by state 3 mitochondria was inhibited in all ischemic groups compared with the sham group (SH vs IR: P = .0052; SH vs IRMB5': P = .0006; SH vs IRMB15': P = .0048), which did not occur in the nonischemic contralateral portion of the same liver (SH vs NI: P = .7652; SH vs NIMB5': P = .059; SH vs NIMB15': P = .3153). The inhibition of the rate of oxygen consumption by state 3 mitochondria was maintained in the presence of MB (IR vs IRMB5': P = .4563; IR vs IRMB15': P = .9021). The respiratory control ratio was reduced in all ischemic groups compared with the sham group, owing to the inhibition of oxygen consumption in state 3 (SH vs IR: P = .0151; SH vs IRMB5': P = .005; SH vs IRMB15': P = .0007). CONCLUSIONS: Methylene blue had no effect on the mitochondrial respiratory parameters studied, but was able to reduce lipid peroxidation, preventing the production of reactive oxygen species (SH vs IRMB15': P = .0210).

Anxiety and Stress Levels on Liver Transplantation Candidates.

The objective of the present study was to determine the anxiety and stress levels of liver transplant candidates during the preoperative period. A cross-sectional, prospective study was conducted on 52 liver transplantation candidates seen at a specialized public hospital outpatient clinic in the interior of the state of São Paulo, Brazil. Data were collected from November 2014 to April 2015 using a self-applicable questionnaire for the assessment of anxiety (State-Trait Anxiety Inventory, short version) and stress (Perceived Stress Scale), in addition to sociodemographic and clinic characterization. The mean (±SD) anxiety level detected was 23.06 ± 5.51 points, with 1.92% of the subjects showing minimum levels (0 to 12 points), 59.62% a medium level (12 to 24 points), 36.54% a moderate level (24 to 36 points), and 1.92% a severe level (36 to 48 points) of anxiety. The mean level on the stress scale was 12.10 ± 5.62 points, with 7.69% of the subjects showing high stress levels. When individuals with good and poor stress levels were compared, a significant difference was observed between them (P = .0004). The Spearman correlation test showed that the higher the stress, the higher the levels of anxiety (r = 0.4258), P < .0001. The present study contributes to the analysis of the mental health of liver transplantation candidates in view of the need for interventions for the improvement of anxiety and stress levels since the waiting period for the organ generates emotional changes that can affect the quality of life of the patient and the success of this complex therapeutic modality.